Background studies for a ton-scale argon dark matter detector (ArDM)

合集下载

传统统计背景减除和阴影检测算法算法

英文回答：The traditional methodology for background subtraction and shadow detection in video surveillance is a widely employed algorithm for the detection of moving objects. This algorithm is based on the construction of a background model for a given scene, which is then utilized topare each frame of the video in order to discern foreground objects. The initial stage of this algorithm involves the formulation of a background model using statistical techniques such as mean or median pixel intensity. Subsequently, this background model is applied to categorize pixels within each frame as either background, foreground, or shadow.视瓶监控中传统的背景减法和阴影检测法是广泛使用的检测移动对象的算法。

这个算法是基于为给定场景构建一个背景模型，然后利用这个模型对视瓶的每个帧进行拓扑，以便辨别前景对象。

该算法的初始阶段涉及使用平均或中位像素强度等统计技术来制定背景模型。

随后，这个背景模型被用于将每个框架内的像素分类为背景，前景，或者阴影。

So, the first part of this algorithm is all about figuring out what's different between each frame and the background. If a pixel'svalue is a lot different from the background, it's labeled as part of the foreground. But sometimes, the background model gets outdated because of changes in lighting or camera noise, and that can cause mistakes. To fix this, the background model needs to be updated constantly to keep up with changes in the scene. And another important thing is detecting shadows, which can look like moving objects. So, wepare the color and brightness of the foreground with the background to try and spot any potential shadows.这个算法的第一部分，都是为了找出每个框架和背景的不同之处。

写长法对高中英语写作影响的实证研究

ContentsAbstract (i)摘要 (iii)List of Tables (iv)List of Abbreviations (v)Chapter One Introduction (1)1.1Background of the Study (1)1.2Purpose of the Study (2)1.3Significance of the Study (2)Chapter Two Literature Review (4)2.1The Overview of the Length Approach (4)2.1.1The Overview of the Length Approach Aboard (4)2.1.2The Overview of the Length Approach at Home (5)2.2The Overview of the Writing Teaching (7)2.2.1The Overview of the Writing Teaching Abroad (7)2.2.2The Overview of the Writing Teaching at Home (9)Chapter Three Theoretical Foundations (12)3.1Output Hypothesis (12)3.2Constructivism (16)3.3Krashen's Affective Filter Hypothesis (19)Chapter Four Research Methodology (24)4.1Research Questions (24)4.2Subjects (24)4.3Instruments (24)4.3.1Questionnaires (24)4.3.2Tests (25)4.3.3Scoring criteria (25)4.4Procedures of the Experiment (26)Step One:Preparing (26)Step Two:Training (27)Step Three:Evaluating (31)4.5Data Collection and Analysis (31)Chapter Five Results and Discussion (33)5.1Results and Discussions of the Writing Tests (33)5.1.1Results and Discussions of the Pre-test (33)5.1.2Results and Discussions of the Post-test (34)5.2Results and Discussions of the Questionnaires (37)Chapter Six Conclusion (42)6.1Major Findings and Implications (42)6.2Limitations (42)6.3Suggestions for Future study (43)References (vi)Appendix I Questionnaire about Learner Attitudes towards the Length Approach (ix)Appendix II Pre-test (xi)Appendix III Scoring criteria (xii)Appendix IV Post-test (xiii)Appendix V A student's writing compositions (xiv) (xv) (xxii)Acknowledgements (xxiii)AbstractEnglish writing,as one of productive skills and communication ways of students'language,is anessential aspect in English learning and teaching.However,writing teaching has always been considered asin foreign language teaching.For many years,researchers have devoted themselves to find out “bottleneck”effective ways to solve this problem and many approaches have been put forward,such as productapproach,process approach and genre approach etc.To some extent,these approaches have improvedE nglish writing students’w riting proficiency.However,the current situation of college students’performance in China is still far from satisfactory.A majority of students lack enthusiasm and are not interested in writing.Given problems existing in English writing,it is urgent to find out new effective ways so as to comprehensively improve students'writing ability.Recently,a new approach-LA,based on some important L2theories as well as the insightful analyses of the situation of writing teaching in China,was initiated by Professor Wang Chuming.The basic assumption of this new approach is that the teachercurrent level of foreign language. constantly adjusts the writing requirements on the basis of students’Through gradually increasing the number of words in composition,students are encouraged to writeincreasingly long compositions so as to strengthen their sense of achievement,enhance their confidence intheir ability to learn foreign language,stimulate further learning and eventually ensure progress in foreignlanguage learning.This new approach has attracted great attention both at home and abroad.The currentstudy,on the basis of the previous researches,aims to investigate the feasibility and validity of applying LAto high school English writing teaching,hoping to change the current situation in writing field and improvestudents'writing confidence and proficiency of their English.80students coming from two parallel classesof high school in Minghu school in Taian participated in this research.By employing instrumentscontaining two English writing tests,two questionnaires and SPSS(Statistical Program for Social Science17.0),this thesis adopted quantitative and qualitative analysis methods in order to answer the followingresearchquestions：1.Can the application of the length approach help senior high school students develop theirself-confidence in their English writing?2.Can the application the length approach in English writing help senior high school students improvetheir writing proficiency in their English writing?After fourteen weeks'experiment,the author comes to the conclusion as follows:i。

TheNewcastle-OttawaScale（NOS）forAssessingthe…

a) study controls for ___________ (select the most important factor) ♦ b) study controls for any additional factor (This criteria could be modified to
Development: Identifying Items
• Identify ‘high’ quality choices with a ‘star’
• A maximum of one ‘star’ for each item within the ‘Selection’ and ‘Exposure/Outcome’ categories; maximum of two ‘stars’ for ‘Comparability’
2. Representativeness of the cases a) consecutive or obviously representative series of cases ♦ b) potential for selection biases or not stated
3. Selection of Controls a) community controls ♦ b) hospital controls c) no description
Selection
1. Is the case definition adequate? a) yes, with independent validation ♦ b) yes, eg record linkage or based on self reports c) no description
Bias and Confounding

formative assessment and the design of instructional systems

120 linkages are then identified. These in turn are shown to have implications for the design of instructional systems which are intended to develop the ability of students to exercise executive control over their own productive activities, and eventually to become independent and fully self-monitoring.
Introduction
This article is about the nature and function of formative assessment in the development of expertise. It is relevant to a wide variety of instructional systems in which student outcomes are appraised qualitatively using multiple criteria. The focus is on judgments about the quality of studentts, how they are made, how they may be refined, and how they may be put to use in bringing about improvement. The article is prompted by two overlapping concerns. The first is with the lack of a general theory of feedback and formative assessment in complex learning settings. The second concern follows from the common but puzzling observation that even when teachers provide students with valid and reliable judgments about the quality of their work, improvement does not necessarily follow. Students often show little or no growth or development despite regular, accurate feedback. The concern itself is with whether some learners fail to acquire expertise because of specific deficiencies in the instructional system associated with formative assessment. The discussion begins with definitions of feedback, formative assessment and qualitative judgments. This is followed by an analysis of certain patterns in teacher-student assessment interactions. A number of causal and conditional

土地利用模型

Ann Reg Sci(2008)42:1–10DOI10.1007/s00168-007-0155-1EDITORIALModelling land-use change for spatial planning supportEric Koomen·Piet Rietveld·Ton de NijsPublished online:6September2007©Springer-Verlag2007Abstract Land-use change is a key factor in the development of the human and physical environment.Models of land-use change help understand this intricate sys-tem and can provide valuable information on possible future land-use conﬁgurations. The latter is crucial for policy makers across the globe that have to deal with such varied topics as:urbanisation,deforestation,water management,erosion control and the like.This paper provides a concise introduction to the current state of land-use models,their applications to spatial policy issues and the main research issues in this ﬁeld.It thus establishes the background for the six papers that make up this special issue on modelling land-use change for spatial planning support.JEL Classiﬁcation C15·C53·R14·R521IntroductionLand use is the most clearly visible result of human interaction with the biophysical environment.In all but the most inhospitable and remote mountain ranges,deserts and forests,man has altered the pristine landscape through various types of use.Besides the obvious residential,commercial and agricultural uses,land can also serve pur-E.Koomen(B)·P.RietveldFaculty of Economics and Business Administration,Vrije Universiteit Amsterdam,De Boelelaan1105,1081HV Amsterdam,The Netherlandse-mail:ekoomen@feweb.vu.nlP.Rietvelde-mail:prietveld@feweb.vu.nlT.de NijsNational Institute for Public Health and the Environment(RIVM),PO Box1,3720BA,Bilthoven,The Netherlandse-mail:ton.de.nijs@rivm.nl2 E.Koomen et al. poses such as recreation,wood production or biodiversity preservation.The use of land is normally reﬂected in its outward appearance(land cover),but this relation is more complex than is initially nd can simultaneously be used for differ-ent functions(e.g.,agriculture and recreation)or locally have different main functions related to the same cover(e.g.,nature reserve and wood production).In fact,many authors therefore explicitly distinguish between land cover and land use(Lambin et al. 2001;Turner et al.1995).For convenience,we use the term land use predominantly in this and the following papers,referring to both land cover and actual land use.Changes in land use are amongst the most controversial consequences of human actions,as is clear from the heated debate on urban sprawl(Brueckner2000;Glaeser and Kahn2004).The conversion of land may impact soil,water and atmosphere (Meyer and Turner2007)and is therefore directly related to environmental issues of global relevance.The large-scale deforestation and subsequent transformation of agri-cultural land in tropical areas are examples of land-use changes with strong impacts on biodiversity,soil degradation and the material resources to support human needs (Lambin et al.2003).Land-use change is also one of the relevant factors among the determinants of climate change and the relationship between the two is interdepen-dent;changes in land use may impact on the climate whilst climatic change will also inﬂuence opportunities for future land-use(Dale1997;Watson et al.2000).Planners worldwide thus seek to steer land-use developments through a wide range of interven-tions that either constrain certain developments(e.g.,restrictive greenbelt policies)or favour them(e.g.,designation of economic development zones or ecological corri-dors).They also play an active role in shaping the landscape through their own spatial investments in,for example,infrastructure or the creation of more general funds and subsidies,as is exempliﬁed in the Common Agricultural Policy of the European Union.For the formulation of adequate spatial policies the involved parties normally make use of models that simulate possible spatial developments.Such models can support the analysis of the causes and consequences of land-use change(Verburg et al.2004). They facilitate the understanding of the processes at hand and help producing maps of possible future land-use conﬁgurations.It is especially the latter possibility that is the topic of the current special issue.As an introduction to the subsequent papers we will brieﬂy discuss here:the typical,policy-related applications of such land-use models,the main characteristics of these models and the current research topics in this ﬁeld.After providing this general background to the topic of this special issue we will brieﬂy introduce the included papers.2Policy related applications of land-use change modelsSimulations of land-use change provide an important element in studies related to the preparation,development and,to a lesser extent,evaluation of large-scale spatial plans and strategies.Figure1presents these subsequent phases of the spatial planning process as cyclical activity,comparable to the spinning top model for public policy evaluation described by Vedung(1997).Below,we will brieﬂy discuss typical land-use model applications for each of these phases of the spatial planning process.In the preparation phase,simulations of future land use provide policymakers with an impression of the possible developments they face.Based on this knowledge,theyModelling land-use change for spatial planning support3can assess the need for action and start drafting appropriate policy proposals.Typi-cal methods to generate these reference or baseline simulations of future land use are trend analysis and scenario studies.Trend analysis can be used to simulate the possible future state of land-use systems on the basis of observed,past spatial developments. By using various statistical techniques,it is relatively easy to represent autonomous land-use developments as an extrapolation of current trends(Schneider and Pontius 2001;Serneels and Lambin2001).However,such an approach makes no attempt to actually understand the processes that drive land-use change and thus misses a clear theoretical foundation.It is,furthermore,not well suited to simulate long-term developments,non-linear pathways of change or the possible impacts of diverging socio-economic developments.Additional theoretical insights are thus welcomed in these basic empirical–statistical models(Parker et al.2003;Veldkamp and Lambin 2001)and such examples are provided by,amongst others,Chomitz and Gray(1996) and Geoghegan et al.(2004).Scenario analyses are especially suited for long-term studies that deal with a wide array of possible developments and the implied uncertainties.By systematically describing several alternative views of the future,one can simulate a broad range of possible spatial developments,thus offering a full overview of the potential land-use nd-use models are used here to indicate possible future land-use patterns according to the speciﬁed scenario conditions,as is demonstrated in numer-ous applications(De Nijs et al.2004;Frenkel2004;Solecki and Oliveri2004;Verburg et al.2008).It is important to note here that each individual outlook to the future in a scenario-study will not necessarily contain the most likely prospects,but,as a whole, the simulations provide the bandwidth of possible changes(Dammers2000).It is not necessary to develop scenarios that are as probable as possible.Instead,the scenar-ios should stir the imagination and broaden the view of the future.As indicated by Xiang and Clarke(2003)important aspects of useful scenario analyses are:plausi-ble unexpectedness and informational vividness.A speciﬁc approach that generates possible alternative solutions to land-use allocation problems is offered by optimisa-tion techniques.These calculate an optimal land-use conﬁguration based on a set of prior conditions,criteria and decision variables(Aerts2002;Pijanowski et al.2002).4 E.Koomen et al. Especially the mathematic programming techniques(such as genetic algorithms)that can determine the optimal solution for different,divergent objectives are interesting for policymakers who are interested in the optimal conﬁguration of an area based on different,often conﬂicting,policy goals(Loonen2007).In the subsequent policy development phase,the implementability of different alter-natives is assessed.Trend and scenario-based simulations of future land use can help here when they contain reference to envisaged spatial policies.The resulting land-use simulations will then offer a depiction of their possible outcomes.Policymakers can thus be confronted with the likely outcomes of their decisions as is demonstrated by Ritsema van Eck and Koomen(2008).A more speciﬁc form of this type of ex-ante evaluations is the dedicated assessment of the land-use impact of a single spatially explicit plan or project.Examples of which are offered by studies on the possible impacts of a new location for a large airport(Scholten et al.1999)and assessments of the likely consequences of policy reforms for agricultural land use(Sheridan et al. 2007;Van Meijl et al.2006).These studies might be combined with trend analyses to specifically assess the additional impact of the selected project.The application of land-use models in the evaluation of the impacts of actually implemented policies and strategies is rare,but Geurs and van Wee(2006)provide an interesting exception in their ex-post evaluation of30years of urban development in the Netherlands.3Land-use model characteristics and research prioritiesRecent surveys of operational models for land-use change are numerous.Briassoulis (2000)offers an extensive discussion of the most commonly used land-use change models and their theoretical backgrounds.Waddell and Ulfarson(2003)and Verburg et al.(2004)offer more concise overviews and focus on the future directions of research in thisﬁeld.A cross-sectional overview of current progress on the analysis of land-use change processes,the exploration of new methods and theories and the appli-cation of land-use simulation models is documented in a recent book of Koomen et al.(2007).All surveys show a heterogeneous group of model approaches with con-siderable differences regarding their theoretical backgrounds,starting points,range of applications,mon characteristics to distinguish between models include their temporal resolution(dynamic vs.static models),spatial resolution(zones vs. grids),central objective(land use nd user),simulation approach(determinis-tic vs.probabilistic),simulation process(transformation vs.allocation)and level of integration(sector speciﬁc vs.integrated).A more in-depth discussion on these charac-teristics and many theories and methods that underlie most current models is provided elsewhere(Koomen and Stillwell2007).The ongoing advances in computing tech-nology and the rapidly increasing amounts of ever more detailed geographical data-sets help modellers worldwide to develop faster andﬁner scaled models of land-use change.Those developments have made it also possible to explore new data-demand-ing and computing-intensive modelling approaches that simulate the behaviour of groups of stakeholders or agents(Parker et al.2003)or microsimulate at the level of individuals(Waddell et al.2003).New technological developments in theﬁeld ofModelling land-use change for spatial planning support5 (three-dimensional)visualisation are particularly helpful in sharing land-use simula-tion results with policy makers and other stakeholders(Borsboom-van Beurden et al. 2006;Rodríguez et al.2007).Combining the strengths of all available concepts,approaches and techniques in stead of elaborating on the approach belonging to the modeller’s own discipline is regarded as one of the most important tasks for future research(Verburg et al.2004). More specifically they list the following priorities in developing a new generation of land-use models:1.Better address the multi-scale characteristics of land-use systems by encompass-ing the scale dependencies of the interrelated socio-economic and biophysical processes at various levels.2.Develop new techniques to assess and quantify neighbourhood effects to betterunderstand the use of such small-scale dependencies that are common in cellular automata based models.3.Pay explicit attention to temporal dynamics to properly incorporate issues as pathdependency,nonlinear pathways of change,feedbacks and time lags.This issue is closely related to the validation of models.4.Further integration of techniques and methods developed in different disciplinesis necessary for modellers to move beyond their own disciplinary traditions and construct truly multidisciplinary models.5.Assess the effects of land-use change and their feedback on land use following pro-cesses as,for example,soil degradation and infrastructure development induced urbanisation.6.Address the interaction between urban and rural areas that is,for example,mani-fest in the possibly unequal development of these areas and the emergence of new multifunctional land-use types.The papers in this special issue deal with a number these issues as will be discussed below.4Layout special issueThis special issue presents a number of papers that aim to strengthen the link between land-use models and their policy-related applications.Theﬁrst two papers(Hagoort et al.2008;Pontius et al.2008)deal with the calibration and validation of land-use models.A necessaryﬁrst step to conﬁdently apply any model of land-use change in a policy oriented context.The papers discuss,amongst others,the validity of model out-comes at various scales and the quantiﬁcation of neighbourhood rules.The following two papers(Shiftan2008;Verburg et al.2008)highlight the importance of integrating different modelling approaches,one of them presenting a multi-scale,multi-model approach to analyzing land-use change.The last two papers(Frenkel and Ashkenazi 2008;Ritsema van Eck and Koomen2008)focus on developing policy-related indica-tors to assess the effects of land-use change,and give explicit attention to the impacts of urbanisation.Table1list the included papers,their relation to the research issues introduced before and the policy themes they try to address.A short introduction to the papers is provided below.6 E.Koomen et al. Table1Overview of the included papers,their related research issues and the policy themes they addressContribution scaledependencies NeighbourhoodeffectsTemporaldynamicsMethodologicalintegrationLand-usechangeeffectsUrban ruralinteractionPolicy themesPontius et al.X Various policythemes;methodologicalcontributionHagoort et al.X X Various policythemes;methodologicalcontributionVerburg et al.X X X X Urbanisation;agricultural landabandonmentShiftan X X Urbanisation andtravel behaviour Frenkel andAshkenaziX X UrbanisationRitsema van Eck and Koomen X X Urbanisation;land-use diversity4.1Calibration and validation of land-use modelsPontius and a large number of other land-use modelling researchers apply methods of multiple resolution map comparison to quantify characteristics for13applications of9different popular peer-reviewed land-change models.Each modelling application simulates change of land categories in raster maps from an initial time to a subsequent time.For each modelling application,the statistical methods compare:(1)a reference map of the initial time,(2)a reference map of the subsequent time,and(3)a prediction map of the subsequent time.The three possible two-map comparisons for each appli-cation characterize:(1)the dynamics of the landscape,(2)the behaviour of the model, and(3)the accuracy of the prediction.The three-map comparison for each application speciﬁes the amount of the prediction’s accuracy that is attributable to land persistence versus land change.Results show that the amount of error is larger than the amount of correctly predicted change for12of the13applications at the resolution of the raw data.The applications are summarized and compared using two statistics:the null resolution and theﬁgure of merit.According to theﬁgure of merit,the more accurate applications are the ones where the amount of observed net change in the reference maps is larger.This paper facilitates communication among land change modellers, because it illustrates the range of results for a variety of models using scientifically rigorous,generally applicable,and intellectually accessible statistical techniques.Hagoort,Geertman and Ottens investigate which,how and to what extent land-use related neighbourhood effects play a role in urban dynamics.The inclusion of such effects is the starting point in many Cellular Automata based models of land-use change that support spatial planning.Their research shows that regional and tempo-ral calibration of neighbourhood rules is a reﬁnement in the application this type of land-use models that pays off by increasing the validity of the model outcomes.This questions the appropriateness of land-use model applications that simulate the land-use changes nationally and use the results for regional planning purposes.RegionallyModelling land-use change for spatial planning support7 and temporally calibrated neighbourhood rules better“explain”past land-use changes and their application allows for a better evaluation and justiﬁcation of spatial policy scenarios and their effects on future land-use dynamics.4.2Integrating different modelling approachesVerburg,Eickhout and Van Meijl describe a methodology in which a series of models has been used to link global-level developments inﬂuencing land use to local-level impacts.It is argued that such an approach is needed to properly address the processes at different scales that give rise to the land use dynamics in Europe.The global eco-nomic model ensures an appropriate treatment of macro-economic,demographic and technology developments and changes in agricultural and trade policies inﬂuencing the demand and supply for land use related products while the integrated assessment model accounts for changes in productivity as a result of climate change and global land allocation.The land-use change simulations at a high(1km2)spatial resolu-tion make use of country speciﬁc driving factors that inﬂuence the spatial patterns of land use,accounting for the spatial variation in the biophysical and socio-economic environment.Results indicate the large impact abandonment of agricultural land and urbanization may have on future European landscapes.The high spatial and thematic resolution of the results allows the assessment of impacts of these changes on different environmental indicators,such as carbon sequestration and biodiversity.The global assessment allows,at the same time,to account for the tradeoffs between impacts in Europe and effects outside Europe.Shiftan discusses the advantages and potential of activity-based models for ana-lyzing the effect of land-use policies on travel behaviour.He suggests improvements that will extend the general framework to achieve a better understanding of travellers’responses to various land-use policies and shows its advantages over trip-based models, which simply do not have such capabilities.The improved activity-based approach is illustrated through a case study based on the Portland activity-based model combined with a stated-preference residential choice model.A package of land-use policies—including improved land use,school quality,safety,and transit service in the city centre—is introduced,and their effect on household redistribution and regional travel is tested using this integrated framework.The results of this case study show that the effects of the land-use policies introduced had only marginal effects on regional travel.4.3Developing policy-related indicatorsFrenkel and Ashkenazi measure and analyze urban sprawl in Israel,based on a large sample of urban settlements.Higher sprawl rates were found to correlate significantly with higher population and land-consumption growth rates,which imply a higher con-sumer preference to reside in more sprawling patterns.Variables that are linked with sprawl in Western countries were usually found to be significant in Israel,as well; however,unlike other Western countries,urban sprawl in Israel is rather spatially dispersed,and not necessarily found on the edges of metropolitan areas.Based on8 E.Koomen et al. theirﬁndings,the authors call for the implementation of more interdisciplinary sprawl measures such as transportation and accessibility,aesthetic and ecological policies.Ritsema van Eck and Koomen present two sets of functional indicators that were implemented and tested for the assessment of spatial aspects of future land-use con-ﬁgurations as simulated by a land-use model.This is potentially useful for the ex-ante evaluation of spatial planning policies.The indicators were applied in a Dutch case study and relate to two important themes in Dutch spatial planning:compact urban-isation and mixing of land uses.After a short introduction of these themes,the sets of indicators are presented which are used for their evaluation.These indicators are applied to simulations based on two opposing scenarios for land-use development in the Netherlands up to2030.The proposed indicators allow for a critical compari-son of the land-use patterns in the two scenarios with respect to the selected policy themes.Single indicators capture individual aspects of urbanisation like magnitude, spatial pattern,concentration,compactness and mixing of land uses.It is,however, the combined use of composition and conﬁguration indicators at various scale levels that makes it possible to unambiguously interpret the projected spatial developments. Acknowledgments We thank the Dutch National research programme“Climate Changes Spatial Plan-ning”and the“Environment,Surroundings and Nature”(GaMON)research programme of the Netherlands organization for scientiﬁc research(NWO)for sponsoring the work involved in organizing this special issue.Furthermore,we would like to thank the Organising Committee of the European Regional Science Association for allowing a special“Modelling Land-Use Change”session to be held at the ERSA2005 conference in Amsterdam.It was the success of this occasion that provided the inspiration for this special st,but not least,we are particularly grateful to the authors and reviewers who contributed their papers and valuable comments to this issue.ReferencesAerts J(2002)Spatial decision support for resource allocation.PhD Dissertation,Universiteit van AmsterdamBrueckner JK(2000)Urban sprawl:diagnosis and remedies.Int Reg Sci Rev23(2):160–171 Borsboom-van Beurden JAM,Van Lammeren RJA,Bouwman AA(2006)Linking land use 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Policy21(4):357–369Frenkel A,Ashkenazi M(2008)The integrated sprawl index;measuring the urban landscape in Israel.Ann Reg Sci(this issue)Geoghegan J,Schneider L,Vance C(2004)Temporal dynamics and spatial scales:Modeling deforestation in the southern Yucatán peninsular region.Geojournal61(4):353–363Modelling land-use change for spatial planning support9 Geurs K,Van Wee B(2006)Ex-post evaluation of thirty years of compact urban development in the Netherlands.Urban Studies43(1):139–160Glaeser E,Kahn M(2004)Sprawl and urban growth.In:Henderson V,Thisse JF(eds)Handbook of regional and urban economics:cities and geography,handbooks in economics,vol4,Elsevier,Amsterdam Hagoort MJ,Geertman S,Ottens HFL(2008)Spatial externalities,neighbourhood Rules and CA land-use modelling.Ann Reg Sci(this issue)Koomen E,Stillwell J(2007)Modelling land-use change.Chapter 1.In:Koomen E,Stillwell J, Bakema A,Scholten HJ(eds)Modelling land-use change;progress and applications.Springer, Dordrecht,pp1–21Koomen E,Stillwell J,Bakema A,Scholten HJ(2007)Modelling land-use change;progress and applica-tions.In:Geojournal library,vol90.Springer,DordrechtLambin EF,Turner BL,Geist HJ,Agbola SB,Angelsen A,Bruce JW,Coomes OT,Dirzo R,Fischer G, Folke C,George PS,Homewood K,Imbernon J,Leemans R,Li X,Moran EF,Mortimore M, Ramakrishnan PS,Richards JF,Skanes H,Stone GD,Svedin U,Veldkamp TA,V ogel C,Xu J(2001) The causes of land-use and land-cover change,moving beyond the myths.Glob Environ Change 11(4):5–13Lambin EF,Geist HJ,Lepers E(2003)Dynamics of land-use and land-cover change in tropical regions.Ann Rev Environ Resour28:205–241Loonen W,Heuberger P,Kuijpers-Linde M(2007)Spatial optimisation in land-use allocation problems.Chapter9.In:Koomen E,Stillwell J,Bakema A,Scholten HJ(eds)Modelling land-use change;progress and applications.Springer,Dordrecht,pp147–165Meyer WB,Turner BL(2007)Changes in land use and land cover.Cambridge University Press,Cambridge Parker DC,Manson SM,Janssen M,Hoffmann MJ,Deadman PJ(2003)Multi-agent systems for the sim-ulation of land use and land cover change:a review.Ann Assoc Am Geogr93(2):316–340 Pijanowski BC,Brown DG,Manik G,Shellito B(2002)Using neural nets and GIS to forecast land use changes:a land transformation put Environ Urban Syst26(6):553–575Pontius Jr RG,Boersma W,Castella J-C,Clarke K,De Nijs T,Dietzel C,Duan Z,Fotsing E,Goldstein N, Kok K,Koomen E,Lippitt CD,McConnell W,Pijanowski BC,Pithadia S,Mohd Sood A,Sweeney S,Trung TN,Veldkamp TA,Verburg PH(2008)Comparing the input,output,and validation maps for several models of land change.Ann Reg Sci(this issue)Ritsema van Eck J,Koomen E(2008)Characterising urban concentration and land-use diversity in simu-lations of future land use.Ann Reg Sci(this issue)Rodríguez JN,Omtzigt N,Koomen E,De Blois F(2007)3D visualisations in simulations of future land use:exploring the possibilities of new,standard visualisation tools.Paper for the joint workshop on Visualization and Exploration of Geospatial Data,ISPRS/ICA/DGfK,27–29June,2007,Stuttgart, GermanySchneider LC,Pontius Jr RG(2001)Modeling land-use change in the Ipswich Watershed,Massachusetts, USA.Agric Ecosyst Environ85:83–94Scholten HJ,Van de Velde RJ,Rietveld P,Hilferink M(1999)Spatial information infrastructure for scenario planning:the development of a land use planner for Holland.In:Stillwell J,Geertman S,Openshaw S(eds)Geographical information and planning.Springer,Heidelberg,pp112–134Serneels S,Lambin EF(2001)Proximate causes of land-use change in Narok District,Kenya:a spatial statistical model.Agric Ecosyst Environ85:65–81Sheridan P,Schroers JO,Rommelfanger E(2007)GIS-based modelling of land-use systems;EU Common Agricultural Policy reform and its impact on agricultural land use and plant species richness.Chapter21.In:Koomen E,Stillwell J,Bakema A,Scholten HJ(eds)Modelling land-use change;progress andapplications.Springer,Dordrecht,pp375–389Shiftan Y(2008)The use of activity-based modeling to analyze the effect of land-use policies on travel behavior.Ann Reg Sci(this issue)Solecki WD,Oliveri C(2004)Downscaling climate change scenarios in an urban land use change model.J Environ Manage72:105–115Turner II BL,Ross RH,Sanderson S,Fischer G,Fresco LO,Leemans R(1995)Land Use and land-cover change-science/research plan.IGBP report35/HDP report7.Stockholm/Geneva,IGBP/HDPVan Meijl H,Van Rheenen T,Tabeau A,Eickhout B(2006)The impact of different policy environments on agricultural land use in Europe.Agric Ecosyst Environ114(1):21–38Vedung E(1997)Public policy and program evaluation.Transaction Publishers,New Brunswck,NJ Veldkamp A,Lambin EF(2001)Editorial;predicting land-use change.Agric Ecosyst Environ85:1–6。

tpo54三篇阅读原文译文题目答案译文背景知识

托福阅读tpo54全套解析阅读-1 (2)原文 (2)译文 (4)题目 (5)答案 (9)背景知识 (10)阅读-2 (10)原文 (10)译文 (12)题目 (13)答案 (18)背景知识 (20)阅读-3 (25)原文 (26)译文 (27)题目 (28)答案 (33)背景知识 (35)阅读-1原文The Commercialization of Lumber①In nineteenth-century America, practically everything that was built involved wood.Pine was especially attractive for building purposes.It is durable and strong, yet soft enough to be easily worked with even the simplest of hand tools.It also floats nicely on water, which allowed it to be transported to distant markets across the nation.The central and northern reaches of the Great Lakes states—Michigan, Wisconsin, and Minnesota—all contained extensive pine forests as well as many large rivers for floating logs into the Great Lakes, from where they were transported nationwide.②By 1860, the settlement of the American West along with timber shortages in the East converged with ever-widening impact on the pine forests of the Great Lakes states. Over the next 30 years, lumbering became a full-fledged enterprise in Michigan, Wisconsin, and Minnesota. Newly formed lumbering corporations bought up huge tracts of pineland and set about systematically cutting the trees. Both the colonists and the later industrialists saw timber as a commodity, but the latter group adopted a far more thorough and calculating approach to removing trees. In this sense, what happened between 1860 and 1890 represented a significant break with the past. No longer were farmers in search of extra income the main source for shingles, firewood, and other wood products. By the 1870s, farmers and city dwellers alike purchased forest products from large manufacturingcompanies located in the Great Lakes states rather than chopping wood themselves or buying it locally.③The commercialization of lumbering was in part the product of technological change. The early, thick saw blades tended to waste a large quantity of wood, with perhaps as much as a third of the log left behind on the floor as sawdust or scrap. In the 1870s, however, the British-invented band saw, with its thinner blade, became standard issue in the Great Lakes states' lumber factories.Meanwhile, the rise of steam-powered mills streamlined production by allowing for the more efficient, centralized, and continuous cutting of lumber. Steam helped to automate a variety of tasks, from cutting to the carrying away of waste. Mills also employed steam to heat log ponds, preventing them from freezing and making possible year-round lumber production.④For industrial lumbering to succeed, a way had to be found to neutralize the effects of the seasons on production. Traditionally, cutting took place in the winter, when snow and ice made it easier to drag logs on sleds or sleighs to the banks of streams. Once the streams and lakes thawed, workers rafted the logs to mills, where they were cut into lumber in the summer. If nature did not cooperate—if the winter proved dry and warm, if the spring thaw was delayed—production would suffer. To counter the effects of climate on lumber production, loggers experimented with a variety of techniques for transporting trees out of the woods. In the 1870s, loggers in the Great Lakes states began sprinkling water on sleigh roads, giving them an artificial ice coating to facilitate travel. The ice reduced the friction and allowed workers to move larger and heavier loads.⑤But all the sprinkling in the world would not save a logger from the threat of a warm winter. Without snow the sleigh roads turned to mud. In the 1870s, a set of snowless winters left lumber companies to ponder ways of liberating themselves from the seasons. Railroads were one possibility.At first, the remoteness of the pine forests discouraged common carriers from laying track.But increasing lumber prices in the late 1870s combined with periodic warm, dry winters compelled loggers to turn to iron rails. By 1887, 89 logging railroads crisscrossed Michigan, transforming logging from a winter activity into a year-round one.⑥Once the logs arrived at a river, the trip downstream to a mill could be a long and tortuous one.Logjams (buildups of logs that prevent logs from moving downstream) were common—at times stretching for 10 miles—and became even more frequent as pressure on the northern Midwest pinelands increased in the 1860s. To help keep the logs moving efficiently, barriers called booms (essentially a chain of floating logs) were constructed to control the direction of the timber. By the 1870s, lumber companies existed in all the major logging areas of the northern Midwest.译文木材的商业化①在19世纪的美国，几乎所有建筑材料都含有木材。

实验室放大研究的英文表述

实验室放大研究的英文表述Laboratory Scale-up Studies.Laboratory scale-up studies are a crucial part of the research and development process, bridging the gap between small-scale experiments and industrial-scale production. These studies aim to assess the feasibility and scalability of processes, products, or systems under realistic conditions, while considering factors such as cost, time, and safety.The process of scaling up involves increasing the size and complexity of a system while maintaining its fundamental characteristics and performance. This is a challenging task, as it requires careful consideration of various factors such as equipment size, process parameters, material properties, and heat and mass transfer rates.One of the main objectives of laboratory scale-up studies is to determine the optimal operating conditionsfor a process or system. This involves identifying the critical parameters that affect performance and stability, and optimizing them to achieve the desired output. For example, in the pharmaceutical industry, scale-up studies are conducted to determine the best temperature, pressure, and reaction time for the synthesis of a drug.Another important aspect of laboratory scale-up studies is the validation of process models. These models are developed based on small-scale experimental data and used to predict the behavior of the system at larger scales. Validation involves comparing the predictions of the model with actual experimental results obtained at different scales. This helps to identify any discrepancies and improve the accuracy of the model.In addition to process optimization and model validation, laboratory scale-up studies also involve the assessment of scalability. Scalability refers to theability of a process or system to be easily expanded or reduced in size without significant changes in its performance. To assess scalability, researchers compare theperformance of the system at different scales and identify any challenges or limitations that may arise during the scale-up process.Laboratory scale-up studies also play a crucial role in risk assessment and safety evaluation. As the scale of a process or system increases, the potential for accidents or failures also increases. By conducting scale-up studies, researchers can identify potential hazards and develop safety measures to mitigate these risks.To conduct effective laboratory scale-up studies, it is essential to have a well-designed experimental setup that allows for accurate measurement and control of process parameters. This includes selecting appropriate equipment and instrumentation, as well as developing standardized operating procedures. Additionally, it is important to have a team of experienced researchers who understand the underlying principles of the process or system and can make informed decisions based on the experimental data.In summary, laboratory scale-up studies are essentialfor evaluating the feasibility and scalability of processes, products, or systems. These studies help to identifyoptimal operating conditions, validate process models, assess scalability, and evaluate safety. By conducting rigorous and well-designed scale-up studies, researcherscan ensure that their research findings translate into successful industrial applications.。

Songliao Basin of Northeast China and its stratigraphic and paleoclimate implications

The ﬂoating astronomical time scale for the terrestrial Late Cretaceous Qingshankou Formation from the Songliao Basin of Northeast China and its stratigraphic and paleoclimate implicationsHuaichun Wu a ,b ,⁎,Shihong Zhang a ,Ganqing Jiang c ,Qinghua Huang daState Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Beijing,100083,China bSchool of Marine Science,China University of Geosciences,Beijing,100083,China cDepartment of Geoscience,University of Nevada,Las Vegas,NV 89154-4010,U.S.A.dExploration and Development Research Institute of Daqing Oil Field Corporation Ltd.,Daqing,Heilongjiang,163712,Chinaa b s t r a c ta r t i c l e i n f o Article history:Received 19May 2008Received in revised form 14October 2008Accepted 8December 2008Available online 21January 2009Editor:P.DeMenocalKeywords:Late Cretaceous Milankovitch cyclesastronomical time scale (ATS)lacustrine anoxic event 1(LAE1)Songliao BasinThe Upper Cretaceous Qingshankou Formation (K 2qn)in the Songliao Basin (SLB)of Northeast China consists of up to 550m thick,lacustrine mudstone and shale that constitute one of the most important source rocks of the Daqing oil ﬁeld.A high-resolution cyclostratigraphic analysis of the natural gamma-ray logging from 10wells of the Qingshankou Formation (K 2qn)reveals orbital cycles of precession (20ka),obliquity (40ka)and eccentricity (100ka and 405ka),providing strong evidence for astronomically driven climate changes in the Late Cretaceous terrestrial environments.Floating astronomical time scales (ATS)are established for all sections,which demonstrate variable durations of K 2qn across the basin (1.09Ma –5.20Ma)and strong diachroneity of the lacustrine strata.Four periods of high depositional rates can be identi ﬁed in the central parts of the basin,possibly recording deposition during times of sustained wet climate and high chemical weathering.An ATS established from well M206in the central depression zone of the basin,where the most complete and stable Milankovitch cycles are present,suggests that the maximum duration of the K 2qn is 5.20Ma (from 94.27Ma to 89.07Ma;Late Cenomanian to Early Coniacian).The lacustrine anoxic event 1(LAE1)at the Cenomanian –Turonian boundary lasted ~210–310ka,during which the most proli ﬁc petroleum source rocks in SLB were deposited.The onset (~94.21–94.18Ma)and duration (~210–310Ka)of LAE1in SLB are comparable to those of the oceanic anoxic event 2(OAE2;onset at 94.21Ma and duration of ~320–900ka),suggesting that the same trigger mechanism,such as increased atmospheric CO 2from large-scale igneous activity,may have initiated high primary productivity and organic carbon burial in both marine and terrestrial systems.©2009Elsevier B.V.All rights reserved.1.IntroductionThe Cretaceous represents one of the warmest periods of the Phanerozoic eon and a time with signi ﬁcant ocean anoxic events (OAEs).Establishing a high-precision chronostratigraphic framework is fundamental for a better understanding of the global climate change under the Cretaceous supergreenhouse conditions.Owing to the limitations of radiometric ages and paleontological data in general,the astronomical time scale (ATS),established by tuning astronomical forcing signals recorded in sedimentary strata,plays critical roles for de ﬁning and correlating the Cretaceous paleoclimatic/paleoceano-graphic events including OAEs (e.g.Fiet et al.,2006;Li et al.,2008;Locklair and Sageman,2008;Mitchell et al.,2008).With the progresses made in the last decade,it is anticipated that an ATS covering the entire Cretaceous Period will be completed in a few years (Hinnov and Ogg,2007).The existing ATS,however,is restricted to marine strata.There is an immediate need to establish the Cretaceous ATS from terrestrial sedimentary basins so that the marine and terrestrial records can be compared and a better understanding of the Cretaceous Earth system change can be achieved.Continental rift basins are unique repositories for long-term palaeoclimate records (Olsen and Kent,1999).Lacustrine mudstone and shales deposited in continental rift basins,due to their sensitivity to changes in precipitation –evaporation ratios and/or water-level changes,are particularly suitable for high-resolution cyclostratigraphic studies (e.g.,Olsen and Kent,1999;Prokoph and Agterberg,2000)and for establishing astronomical time scales with resolution potentially down to 0.02to 0.40Ma (e.g.,Hinnov,2004;Hinnov and Ogg,2007).Earth and Planetary Science Letters 278(2009)308–323⁎Corresponding author.School of Marine Science,China University of Geosciences,Xueyuan Road 29,Haidian District,Beijing 100083,China.Tel.:+861082334699;fax:+861082320065.E-mail addresses:whcgeo@ ,whccugb@ (H.Wu).0012-821X/$–see front matter ©2009Elsevier B.V.All rights reserved.doi:10.1016/j.epsl.2008.12.016Contents lists available at ScienceDirectEarth and Planetary Science Lettersj o u r n a l h o m e p a g e :w ww.e l s e v i e r.c o m /l o c a t e /e p s lThe Songliao Basin in northeastern China is one of the largest Cretaceous continental rift basins in the world(Fig.1).Well-preserved Cretaceous lacustrine deposits in this basin provide a unique opportunity for the construction of terrestrial Cretaceous ATS. Particularly,the Upper Cretaceous Qingshankou Formation(K2qn) consists of up to550m thick,black mudstone,shale and oil shale that have attracted considerable attention regarding their potential linkage with Milankovitch climate forcing(e.g.,Wu et al.,2007;Cheng et al., 2008).The basal interval of this unit is enriched in oil shale and was considered as deposits during a lacustrine anoxic event(Huang et al., 1998,2007).This event,referred to as lacustrine anoxic event1 (LAE1),has been suspected to be time equivalent to the oceanic anoxic event2(OAE2),but the lack of age controls prevents a chronostrati-graphic correlation with the marine record.In this paper,we present a cyclostratigraphic study based on the high-resolution natural gamma-ray logging of the Qingshankou Formation from10wells in an east–west transect across the Songliao Basin(Fig.2).The major objective of this study is to establish an astronomically calibrated time scale(ATS)for the Late Cretaceous lacustrine strata.With the newﬂoating ATS,we discuss(1)the stratigraphic correlation across the basin and temporal variations in sedimentary rates,(2)the duration of the ostracod biozones constrained by the ATS that may be useful for stratigraphic correlation between terrestrial and marine successions,and(3)the duration of the lacustrine anoxic event1(LAE1)and its correlation with the oceanic anoxic event2(OAE2).2.Geological setting2.1.Tectonics and stratigraphyGeographically,the Songliao Basin(SLB)in northeastern China is surrounded by the Great Xing'an Mountains in the west,the Lessar Xing'an Mountains in the north and the Zhangguangcai Mountains in the east(Fig.1a–c).The southern margin of the basin is separated from the North China plate by the Late Paleozoic Chifeng–Kaiyuan fault zone (Sun et al.,2007).The tectonic evolution of the SLB can be divided into (1)a pre-rift phase,(2)a syn-rift phase,(3)a post-rift phase,and(4)a compression phase(Cheng et al.,2006)(Fig.1d).According to the characteristics of rises and depressions,the SLB can be divided into six ﬁrst-order tectonic units:central depression zone,north plunge zone, west slope zone,northeast uplift zone,southeast uplift zone,and southwest uplift zone(Gao et al.,1994)(Figs.1b and2).The basement of the SLB consists of Precambrian to Paleozoic metamorphic and igneous rocks and Paleozoic to Mesozoic granites (Wang et al.,2006;Pei et al.,2007).Unconformably overlying the basement,up to7000m thick Mesozoic and Cenozoic terrestrial strata are unevenly distributed across the basin(Gao et al.,1994).A simpliﬁed lithostratigraphy of the Songliao Basin is presented in Fig.1d.The Upper Jurassic and Cretaceous strata in SLB is commonly subdivided into two sequences separated by a regional unconformity at the top of the Yingcheng Formation(K1y).The lower sequence includes the Upper Jurassic Huoshiling Formation(J3h)and the Lower Cretaceous Shahezi(K1s)and Yingcheng(K1y)Formations(Fig.1d). These formations are composed of volcanic–volcaniclastic rocks and alluvial–lacustrine sedimentary rocks.The upper sequence consists of seven formations,in ascending order including Denglouku(K1d),Quantou(K2q),Qingshankou (K2qn),Yaojia(K2y),Nenjiang(K2n),Sifangtai(K2s)and Mingshui (K2m)Formations(Fig.1d).The Denglouku Formation(K1d)is composed mainly of alluvial andﬂuvial deposits,while the Quantou Formation(K2q)consists of coarse clastic rocks ofﬂuvial origin in the lower part and lacustrine mudstones in the upper part.The lacustrine sandstone,mudstone,and shale of the Qingshankou (K2qn),Yaojia(K2y)and Nenjiang(K2n)Formations contain the majority of the oil source rocks,reservoir rocks and seals of the Daqing Oilﬁeld(Li,1995)(Figs.1d and2).Unconformably overlying the K2n,the Sifangtai(K2s)and Mingshui(K2m)Formations are mainly composed of siliciclastic rocks deposited from alluvial and deltaic environments during basin inversion.The Qingshankou Formation(K2qn)was deposited during the post-rift thermal subsidence stage.The thickness of this unit varies from30to 550m across the basin(Fig.2).It conformably overlies the Quantou Formation(K2q)and is unconformably or conformably overlain by the Yaojia Formation(K2y).On the basis of lithofacies changes,the K2qn can be divided into three members(Fig.1d).Member1(K2qn1)is mainly composed of deep lacustrine black mudstone and shale.The oil shale at the lower part of the K2qn1is the most important marker for regional stratigraphic correlation.Member2and3of the K2qn(K2qn2+3)consist of interbedded black mudstone and gray-to celadon-colored siltstone. In general,the Qingshankou Formation shows a shallowing—upward trend from deep lacustrine deposit in the lower part(K2qn1)to shallow laustrine,coastal and deltaic deposits in the upper part(K2qn2+3)(Gao et al.,1994;Li,1995;Fig.1b and c).2.2.The age of the Qingshankou Formation(K2qn)Due to the lack of radiometric ages and difﬁculties of deﬁning the duration of terrestrial fossils,the age of the K2qn has been debated. Previous age assignments include(1)late Cenomanian-early Tur-onian(Chen,2000),(2)Cenomanian(Stratigraphy Committee of China,2002;Wan et al.,2005;Sha,2007),(3)Cenomanian–Turonian (Ye et al.,2002),and(4)late Cenomanian–early Coniacian(Wang et al.,2007).Recent radiometric ages from volcanic rocks of the Yingcheng Formation(K1y)and paleontological data from Denglouku(K1d)and Quantou(K2q)Formations support a late Cenomanian age for the Qingshankou(K1qn)Formation.The SHRIMP zircon U-Pb age of111–113Ma(Zhang et al.,2007a)and K/Ar ages of113–136Ma(Wang et al., 2002)from the upper Yingcheng Formation(K1y)suggest that the age of the K1y is Aptian and the age of the K1d should be Albian(Fig.1d). The palynological assemblages of Quantonenpollenites crassatus–Cranwellia striatella and Trilobosporites–Cyathidites–Tricolpopollenites in the upper and lower part of the Quantou Formation(K1q)are of early Turonian and late Cenomanian,respectively(Li,2001).This is consistent with the palynological data from the K1d that have the ages of Early to Middle Albian(Li and Li,2005).Recently,Wang et al.(2007) estimated an age of~94Ma for the K2qn/K2q boundary by extrapolating the stratal thickness of the basin.This is conﬁrmed by their latest,yet to be published radiometric age from the K2qn(Wang, P.J.,personal communications,2008).custrine anoxic events(LAEs)in the SLBPrevious studies suggested that two great lacustrine anoxic events (LAEs)happened in SLB during the deposition of the K2qn1and K2n1+2, and it was proposed that they were related to two great marine transgressions that may have created warm and wet climate conditions (Fig.1d;Gao et al.,1994;Hou et al.,2000;Wang et al.,2001;Li and Pang, 2004).These lacustrine anoxic events was considered crucial for the formation of proliﬁc petroleum source rocks in SLB(Hou et al.,2000; Wang et al.,2001;Li and Pang,2004;Huang et al.,2007).Evidence supporting the lacustrine anoxic event1(LAE1)in K2qn1include(1) deposition ofﬁnely laminated,organic and pyrite—rich black shale and oil shale with a positiveδ13C org spike(Wang et al.,2001;Huang et al., 2007;Huang,2007),(2)extinction of deep water-fauna during LAE1and ﬂourish of diversiﬁed fossil assemblage after LAE1(Huang et al.,1998; Hou et al.,2000),and(3)appearance of28,30-bisnorhopane which originates from a typical anoxic bacteria and preservation of complete C35 hopanes series,lower diasteranes content in mudstone(Hou et al.,2003).The sedimentary sequence of the red terrigeneous sediments of the K2q,K2y and K2s and the black sediments of the K2qn1and K2n1+2309H.Wu et al./Earth and Planetary Science Letters278(2009)308–323310H.Wu et al./Earth and Planetary Science Letters278(2009)308–323may record the alternation of anoxic and oxic lacustrine depositional environments,similar to the redox cycles recorded in Cretaceous marine strata (Fig.1d;Huang,2007).The two great lake anoxic events (LAE1and LAE2in Fig.1d)in K 2qn 1and K 2n 1+2have been suspected to be correlatable with the ocean anoxic events (Hou et al.,2000;Huang,2007;Huang et al.,2007;Wang et al.,2007),but reliable time constraints are lacking.2.4.Biostratigraphy of the K 2qnFossils are abundant in the K 2qn and intensive paleontological studies have been conducted since 1959(e.g.,Gao et al.,1999;Ye et al.,2002).Fossils of the K 2qn include abundant ostracods,conchostraca,ﬁsh,gastropods,bivalves,sporopollen,algae,and vertebrates (Hou et al.,2000;Wan et al.,2007).The identi ﬁcation of these fossils has played an important role in the stratigraphic correlation and division and the reconstruction of paleoecology,paleoenvironment and paleoclimate in the SLB.However,the biostratigraphic resolution is low and many fossils are restricted to either K 2qn 1or K 2qn 2+3.Fossil abundance and diversity also vary among sections across the basin and thus it has been dif ﬁcult to establish a reliable biostratigraphic framework correlatable with that of the marine successions (Wan et al.,2005).Recently,a detailed ostracod biostratigraphy of the K 2qn with 19ostracod biozones was established,based on collections from ﬁve recovered wells (Zhang et al.,2007b ).These ostracod biozones are going to be calibrated by the new ﬂoatingATS so that they can be correlated with the marine biozones in the future.3.Data processingNatural gamma-ray logging records the intensity of the gamma ray emitted during the decay of atomic nuclei of radioactive elements contained in sedimentary rocks.The intensity of gamma ray relates to the amount of 40K,232Th and 238U in rocks.Clay and organic particles have strong capacity of absorbing radioactive elements.The gamma-ray logging curves can therefore re ﬂect changes in the amount of clay and organic materials in sediments,both of which are sensitive to controlling factors such as precipitation –evaporation ratios and lake-level ﬂuctuations induced by climate changes (e.g.,Serra,1984;Hinnov,2004).In this study,natural gamma-ray logs from 10wells penetrating the Qingshankou Formation (K 2qn)across the basin were selected for cyclostratigraphic analysis (Figs.1b,c and 2).The shortest and the longest gamma-ray logs are J32(101m)and G692(544m),respectively (Figs.3–6).In well F64and J32of the west slope zone (Figs.1b and 2),K 2qn unconformably overlies the Upper Jurassic strata,while in the other 8wells K 2qn conformably overlies the Quantou Formation (K 2q).The sampling spacing is from 0.05m to 0.1524m for different logs.Spectral analysis and continuous wavelet analysis were conducted in order to investigate whether the cyclicity records signal resultingFig.1.(a)Location of the Songliao Basin (SLB)in northeastern China.(b)Simpli ﬁed paleogeographic reconstruction of the SLB during deposition of Member 1of the Qingshankou Formation (K 2qn 1).Tectonic units in the SLB and locations of the study wells (black dots)are indicated.Lines A –B mark the position of the cross section in Fig.2.(c)Paleogeographic reconstruction of the SLB during deposition of the K 2qn 2+3.(d)Simpli ﬁed stratigraphy and geological events of the Upper Jurassic to Cretaceous in the SLB.The sea-level change curve is adopted from Gradstein et al.(2004)and the lake-level curve is from Gao et al.(1994).Fig.2.Cross section of the Songliao Basin (modi ﬁed from Wang et al.,2007).Position of sections matches those in Fig.1b.Sections L2and D501are located at the north plunge zone and northeast uplift zone,respectively.Abbreviation N 2t represents the Taikang Formation and the other abbreviations are the same as in Fig.1d.311H.Wu et al./Earth and Planetary Science Letters 278(2009)308–323from astronomical climate forcing.A band-passﬁlter was designed to remove the low(N100m)and high(b1m)frequency variability. Spectral analysis was performed with the REDFIT software package (Schulz and Mudelsee,2002).Wavelet analysis is used to transform depth-related sedimentary signature into wavelengths at distinct depth intervals,useful for detecting and distinguishing abrupt discon-tinuities,cyclicity and changes in sedimentation rate(Prokoph and Agterberg,2000).The wavelet software was provided by Torrence and Compo(1998)and is available at /research/ wavelets/.4.Cyclostratigraphy4.1.Orbital parameters in Late CretaceousAccording to geological and paleomagnetic evidence(Zhao et al., 1990;Chi et al.,2000),the Songliao Basin has been adjacent to the present position in early Late Cretaceous.We used the June21insolation curve at45°N from94to90Ma as a reference(Fig.3a-1),which is calculated using Analyseries2.0(Paillard et al.,1996)and the improved La2004solution(Laskar et al.,2004).Four distinct frequency bands can be observed from the continuous wavelet analysis scalogram(Fig.3a-2), which are consistent with results from spectral analysis.Spectral analysis shows the presence of the principal eccentricity periods of 405ka(E3),125ka(E2)and100ka(E1),principal obliquity periods of 37.5ka(O1)with lesser ones of48ka(O2),56ka and28ka,and principal precession periods of22.5ka(P2),18.4ka(P1)and15.9ka(Fig.3a-3).We will use these periods as the Late Cretaceous“canonical”orbital varia-tions in our study.4.2.Cycle analysis and cyclostratigraphic interpretationParallel bands in the wavelet scalograms show that the spectral power is conﬁned to distinct and relatively continuous period bands for all sections(Fig.3b-l).Spectral analyses reveal distinctive spectral power peaks and the ratio of corresponding periods is ~20:5:2:1,which is similar to the ratio of Milankovitch cyclicities of 405ka:100ka:40ka:20ka(long eccentricity,short eccentricity, obliquity,precession)(Fig.3b-l).We followed the method of Westerhold et al.(2007)to construct a cyclostratigraphy for the K2qn for each section(Figs.4–6).Direct cycle counting and Gaussian band passﬁltering of the data are used.The ﬁrst peak of gamma-ray logging(precession),extracted short and long eccentricity cycles were used as the starting point(Figs.4–6).Strong shifts in the wavelet spectral bands for sections G692(at2100m),L2 (at1770m),F64(at557m and500m)suggest changes in cycle periodicities due to change in sedimentation rates,so we use different Gaussian band passﬁlters to extract orbital forcing cycles(Figs.5and 6).The longest section(M206)in the central depression zone and the shortest section(J32)in the west slope zone were selected as end members for interpreting the results from wavelet and spectral analyses and constructing cyclostratigraphy.In section M206,the total thickness of K2qn is496.8m(from1286m to1782.8m in the well log;Fig.4).The lower part of K2qn(K2qn1)is composed mainly of gray and black mudstone,with thin calcareous mudstone layers and three black oil shale layers.The upper part of K2qn (K2qn2+3)consists mainly of thick,gray to dark-gray mudstone with calcareous mudstone interbeds,but changes to thinly laminated,red silty sandstone and mudstone towards the top(Fig.4a).The gamma-ray values are in the range of~60–180API.Low values correspond to calcareous mudstone,whereas high gamma-ray values are produced by black shale and mudstones.Signiﬁcantly low values at the top of K2qn correspond to the red silty sandstones(Fig.4).The density log has values mostly from1.7to2.3g/cm3,but lower values are found at the top, possibly related to increased porosity in sandstones(Fig.4).Wavelet analysis of both gamma-ray and density logs reveal relatively continuous cycles with periods of68m,39m,13.5–9m,5–3.8m and2.5–1.7m(Fig.3f and g).The lack of a strong shift at periods of39m and13.5–9m in both gamma-ray and density logging suggests that relatively stable sedimentation rate prevailed during the deposi-tion of K2qn,while the variance at shorter periods of5–3.8m and2.5–1.7m probably records short-termﬂuctuations in sediment supply(e.g.,Prokoph and Agterberg,2000).To determine whether the observed cycles in sedimentary strata were formed by astronomical forcing,the most commonly used method is to compare the relative ratio of the observed cycles with that of the Milankovitch cycles(Hinnov,2000;Weedon,2003).The ratios of the major periods of~39m,13.5–9m,5–3.8m and2.5–1.7m from natural gamma-ray and density logging of section M206is 20:5:2:1,which matches well with the Milankovitch cyclicities of 405ka:100ka:40ka:20ka(long eccentricity,short eccentricity, obliquity,precession).Spectral analysis on the full time series of the gamma-ray logging reveals four distinct cycles of14.2–8.9m,4.9–3.8m,2.6–2.3m and1.9–1.7m(Fig.3f and g).The ratio for theﬁve main peaks of these cycles is13.3m:10.3m:4.05m:2.43m:1.9m (123:95:37.5:22.5:17.6).These ratios are similar to the results of spectral analysis on the June21insolation curve at45°N from94to 90Ma(Fig.3a).We thus consider that the sedimentary cyclicity in section M206was formed by orbital forcing(Weedon,2003).The major periods of~39m,13.5–9m,5–3.8m and2.5–1.7m were formed most likely by long(405ka)and short(100ka)eccentricity, obliquity(40ka)and precession(20ka),respectively.The small cycle length of the original natural gamma-ray and density logging curves range from1.7m to2.5m,which are interpreted as precession-related sedimentary cycles(Fig.4).Counting from the base of the K2qn,each cycle is numbered and there are~253precession cycles in both gamma-ray and density logging data(Fig.4).Two Gaussian band-passﬁlters were used toﬁlter the signals of the long and short eccentricity cycles of~39m and13.5–9m,respectively.The ﬁltering outputs of the gamma-ray and density logging are shown in Fig.4.We counted12.8long eccentricity cycles and51.6short eccentricity cycles from the gamma-ray logging,but12.3long eccentricity cycles and50.1short eccentricity cycles from the density logging(Fig.4).There are about0.5long eccentricity and1.5short eccentricity offsets.The underlying reason for this difference is uncertain,but because the cycle bands in the wavelet scalograms and theﬁlter outputs of gamma-ray logging demonstrate more stable and constant signals than those of the density logging(Figs.3f,g and4), and because previous studies demonstrated that gamma-ray readings are more sensitive to variations in lithology and clay–mineral content than other logging tools(Serra,1984;Prokoph and Thurow,2000),we chose the gamma-ray logging data for cyclostratigraphic study for all sections in this study.The total thickness of K2qn in section J32in the west slope zone is 101m(from398m to499m in the well log;Figs.3k and6f).It unconformably overlies the Jurassic volcanic rocks and isFig.3.(a)June21insolation curve at45°N from94to90Ma(a-1),wavelet scalogram(a-2)and spectral analysis(a-3)of the theoretical insolation curve,which are calculated using Analyseries2.0(Paillard et al.,1996)and La2004solution(Laskar et al.,2004).The shaded contours in wavelet scalograms are normalized linear variances,with blue representing low spectral power and red representing high spectral power.Regions below curves on both ends indicate the cone of inﬂuence where edge effects become signiﬁcant.(b)–(f)and(h)–(l)Wavelet scalogram and spectral analyses of the gamma-ray logging of the K2qn in different tectonic zones of the Songliao Basin.(g)Wavelet scalogram(g-1)and spectral analysis(g-2)of the density logging of M206.Letters“d”mark the possible discontinuities.See Figs.1b and2for location of sections,and Figs.4–6for original logging data.312H.Wu et al./Earth and Planetary Science Letters278(2009)308–323313 H.Wu et al./Earth and Planetary Science Letters278(2009)308–323314H.Wu et al./Earth and Planetary Science Letters278(2009)308–323Fig.3(continued).unconformably overlain by sandstones of the second and third member of Yaojia Formation(K2y2+3).In this section,K2qn1is com-posed of purple mudstone and gray muddy siltstone and K2qn2+3 consists mainly of emerald,celadon and purple mudstone with sandstone and muddy siltstone.The parallel bands in the wavelet scalogram of section J32show three cycle periods of16–9m,5.8m and3.2m.Spectral analysis on the full time series reveals two distinct cycle bands of6.2–4.3m and 3.6–2.8m(Fig.3k).These periods has a ratio of5:2:1,which is correlative to the short eccentricity,obliquity and precession ratio of 100ka:40ka:20ka(Fig.3k).Although spectral analysis for this section does not show the peaks of eccentricity cycles,short and long eccentricity cycles were extracted by the Gaussian band passﬁlters according to the wavelet analysis and the variation of gamma-ray logging(Fig.3k).We counted 2.8long eccentricity,10.9short eccentricity and50precession cycles in section J32(Fig.6f).5.Discussion5.1.Astrochronology of the Qingshankou Formation(K2qn)The records from the K2qn in the SLB display excellent precession, obliquity,short and long eccentricity signals(Figs.3–6),and theoreti-cally,every band of signals can be used for tuning to the orbital solutions. However,because the precision of the orbital solution for Mesozoic is limited(Laskar et al.,2004),the high frequency cycles may not be suitable for constructing the ATS.Changes in resonance between the orbits of Earth and Mars may have altered the95to128ka eccentricity. Tidal friction in the Earth–Moon system could slow the Earth's rotation rate over time,increasing the periodicities of precession and obliquity (Laskar et al.,2004).Thus a full-spectrum tuning of the Mesozoic records to the La2004solution is impossible at the moment.Because the long eccentricity cycle(405ka)remains very stable at least back to~250Ma,Fig.4.(a)Simpliﬁed lithology and stratigraphy of the K2qn from well M206.(b)Continuous gamma-ray(red line)and density(blue line)logging of the K2qn from M206with0.125m sampling resolution.The red and blue numbers indicate the number of precession-related cycles.(c)Cycle counting of long eccentricityﬁlter outputs of gamma-ray(red)and density (blue)logging data of the K2qn from M206.(d)Cycle counting of short eccentricityﬁlter outputs of gamma-ray(red)and density(blue)logging data of the K2qn from M206.The long and short eccentricity-related cycles are extracted by Gaussian band passﬁlters withﬁlter frequency of0.0225±0.003cycles/m and0.104±0.013cycles/m,respectively.315H.Wu et al./Earth and Planetary Science Letters278(2009)308–323it was recommended that a Mesozoic astronomically calibrated time scale can be established as a ﬂoating time scale using long eccentricity cycles (Laskar et al.,2004;Hinnov and Ogg,2007).However,the extracted long eccentricity cycles from most sections of the K 2qn are less stable than the short eccentricity cycles (Figs.4–6),which also show more stable and clear signals than other bands of signals in mostwaveletFig.5.Cycle counting of precession (black),long (red)and short (blue)eccentricity of gamma-ray logging data of the K 2qn from sections (a)G692,(b)C503and (c)Z805of the central depression zone.The long and short eccentricity cycles are extracted by Gaussian band pass ﬁlters.Filter frequency for long eccentricity cycles:G692–0.025±0.003(from 1800to 2100m)and 0.019±0.002(from 2100to 2344m)cycles/m;C503–0.0187±0.003cycles/m;Z805–0.0208±0.003cycles/m.Filter frequency for short eccentricity cycles:G692–0.083±0.026cycles/m;C503–0.075±0.01cycles/m;Z805–0.081±0.02cycles/m.Fig.6.Cycle counting of precession (black),long (red)and short (blue)eccentricity of gamma-ray logging data of the K 2qn from sections (a)L2,(b)W209,(c)D501,(d)F64,(e)L271and (f)J32.The long and short eccentricity cycles are extracted by Gaussian band pass ﬁlters.Filter frequency for long eccentricity cycles:L2–0.028±0.005cycles/m;W209–0.0262±0.003cycles/m;D501–0.03125±0.004cycles/m;F64–0.02381±0.003cycles/m;L271–0.01923±0.003cycles/m;J32–0.02439±0.003cycles/m.Filter frequency for short eccentricity cycles:L2–0.108±0.021(from 1449to 1770m)and 0.091±0.01(from 1770to1874m)cycles/m;W209–0.1042±0.015cycles/m;D501–0.1266±0.025cycles/m;F64–0.09375±0.03125cycles/m;L271–0.0746±0.08cycles/m;J32–0.1111±0.033cycles/m.316H.Wu et al./Earth and Planetary Science Letters 278(2009)308–323。

英语词汇学第5章

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Strategies of Background Knowledge in Reading Comprehensionword资料8页

Strategies of Background Knowledge in ReadingComprehensionAbstract：The Schema Theory has indicated that successful activation of background knowledge significantly aids L2 learners’ reading comprehension. The paper，based on the writer’s practical teaching experience， explores some approaches of activating background knowledge and also concludes some reasons for unsuccessful activations as well as suggestions for L2 instructors.1 IntroductionBoth theorists and practitioners agree that “compreh ension is an active process where learners interact with the text， using background knowledge that they bring to the comprehension process as well as the linguistic and rhetorical features of the text itself” （Carrell and Eisterhold 1977）. So it is strongly recommended teachers should be particularly sensitive to the role of background knowledge and teach from a schema-theoretic view to help their students build or activate schemata while comprehending.2 Background Knowledge StrategiesBy far ESL teachers are increasingly concerned about background knowledge strategies that are applied for two aims：（1） to activate students with cues， questions and advance organizers to make connections between their L1 linguistic， cultural， world knowledgeand experience and the topics， skills and competencies at hand；（2） to introduce new content， skills and competencies to provide new contextual knowledge in the target language when these content areas have not yet been exposed to L2 learners. There are numerous such strategies that are applicable in L2 instruction. Here， I introduce some with widely accepted effectiveness.2.1 The K-W-L ModelSchematic researches suggest that L2 learners comprehend better if they are provided authentic， meaningful materials with which they are quite familiar and in which they are highly interested. In the consequent semantic pedagogy study by Donna M. Ogle in 1986，she created the concept of K-W-L Model. K-W-L， an acronym for three key questions （What I Know， What I Want to Learn， and What I Learned） is a teaching model designed to help students learn from nonfiction text in any content area （Ogle 1986）. According to my own experience in adopting this model in my College English instruction， the approach is very effective and welcomed by my students.Take the class of Unit 5 in New Horizon College （Book 1） I have taught for example. The topic is The Trashman. I asked two of the questions at the beginning of the lesson，the K question “What do you know about the topic？” and the W question “What do youwant to know about the topic？” For the first question， students one by one illustrated a brief image of a trashman through their prior knowledge. For the second questions， some students predicted a touching story about a trashman， while others guessed it about some moral issues on how a trashman is treated in the American society and how he himself reacts to possible discrimination. In order for a more effective schema-activation， two students with higher proficiency were asked to describe what a trashman does in the local context and how they look at their job. By then， a basic schema for a specific character had been built up but with two possible content schemata for students to make clear. This schema in content area was soon constructed when we started vocabulary study. At the end of the lesson， the students did the group discussion on the L question “What have you learned about the topic？” I made rounds of the class to make sure that fruitful results have been achieved and my students have reaped the benefits of the schema-based learning. 2.2 Advance Organizer Support Research studies have also validated the striking effects of visual advance organizers on reading and listening comprehension，especially for lower-proficiency L2 learners. Therefore， pictures，graphics， scripts， movies and slides， etc. are strongly recommended in L2 instructions to help unsuccessful learners withan effective schema-activation and better understanding of the target language. For example， reading graded picture books is one of the widely adopted approaches in instructing reading for lower-proficiency L2 learners. The graded picture books provide manageable reading materials and simple stories that can be easily understood. Learners advance forward step by step and develop their comprehension competence bit by bit. What’s more， being able to read and understand story books raise their self-esteem.Maybe another more effective visual organization comes from the advantages of Computer-Aided Instruction （CAI）. By means of video show via computer or Internet，Students’ background knowledge is activated to utmost. Right because of the best practice of utilizing multimedia approaches in facilitating L2 learning， especially its role of stimulating learn er’s interest and better understanding of the target language， the educational authorities in countries all over the world have advocated CAI in L2 classroom in the state level.Other pre-reading activities such as field trips，demonstrations， discussions， debates， role plays，text-previewing， vocabulary pre-learning and key-word/key-concept association activities suggested by Carrell （1984a） are also widely adopted as powerful instructional strategies in China’s L2classrooms. All these activities contribute to effective comprehension by brainstorming learners’ background knowledge on the topic prior to reading， stimulating their curiosity on the subject and encouraging their self-generating and self-monitoring reading.2.3 Culture-based TeachingC arrell and Eisterhold indicated “one of the most obvious reasons why a particular content schema may fail to exist for a reader is that schema is culturally specific and is not part of a particular reader’s cultural background” （Carrell and Eisterhold 1983）. Floyed and Carrell（1987） recommended acultural-content-schema-training to readers’ second language acquisition. Gajdusek （1988）， based on his own research studies and in support of Carrell’s suggestion， provided a four-step approach to build students’ schemata with any literature text：（1） the raise of background information relating to the text；（2） factual in-class work （character， place， time， and event of a text）；（3） analysis （structure， theme， and style of a text）；（4） extending activities （in-class activities， journal writing）.Accordingly， facilitators must try to build a rich linguisticenvironment where learners are exposed to a large supply of authentic reading materials， such as materials about western values， social systems， cultures and customs， etc. In this intentionally created schema-oriented context， learners do culturally loaded reading with aid of in-class activities，appropriate types of content schemata can be constructed so that learners may be able to compensate their linguistic weakness with their learned background knowledge when comprehending such topics. If the strategy is facilitated at learners’ earlier learning stage，they will for sure benefit from it in their future L2 acquisition.3 Limitation and ImplicationsHowever，teachers in some areas of China find little support from the schema theory for reasons they are not quite certain about. As Rumelhart has stated， if our schemata are incomplete and do not provide an understanding of the incoming data from the text we will have problems processing and understanding the text （Rumelhart 1977）. The “incomplete schemata” here， as to L2 learner， is theoretically attributed to two types of deficiencies： linguistic deficiency and cultural deficiency. The former means L2 l earner’s language deficits in vocabulary， grammar， cohesion and discourse structures， while the latter refers to an unfamiliarity with content of the text in terms of cultural features of the targetlanguage. Yet， poor readers in the traditional L2 context are usually encouraged to expand their vocabulary and to gain greater control over complex syntactic structures. The unilateral solution to less effective L2 comprehension does help much， rather leads to a demotivation in overall performance.Therefore， teachers should be simultaneously aware of inappropriate schemata stimulated or absent schema-activation in reading or listening comprehension both due to helpless language proficiency and due to ambiguous topics with unfamiliar cultures. Since a growing body of empirical has been accomplished insofar and several applicable approaches suggested to schematic classroom instruction， teachers must have a good mastery of the theory as well as applicable approaches that can bring substantial benefits in compens ating students’ linguistic deficiencies and in combining L2 acquisition with culture understanding.希望以上资料对你有所帮助，附励志名言3条：：1、世事忙忙如水流，休将名利挂心头。

专八英语阅读

英语专业八级考试TEM-8阅读理解练习册（1）(英语专业2012级)UNIT 1Text AEvery minute of every day, what ecologist生态学家James Carlton calls a global ―conveyor belt‖, redistributes ocean organisms生物.It’s planetwide biological disruption生物的破坏that scientists have barely begun to understand.Dr. Carlton —an oceanographer at Williams College in Williamstown,Mass.—explains that, at any given moment, ―There are several thousand marine species traveling… in the ballast water of ships.‖ These creatures move from coastal waters where they fit into the local web of life to places where some of them could tear that web apart. This is the larger dimension of the infamous无耻的，邪恶的invasion of fish-destroying, pipe-clogging zebra mussels有斑马纹的贻贝.Such voracious贪婪的invaders at least make their presence known. What concerns Carlton and his fellow marine ecologists is the lack of knowledge about the hundreds of alien invaders that quietly enter coastal waters around the world every day. Many of them probably just die out. Some benignly亲切地，仁慈地—or even beneficially — join the local scene. But some will make trouble.In one sense, this is an old story. Organisms have ridden ships for centuries. They have clung to hulls and come along with cargo. What’s new is the scale and speed of the migrations made possible by the massive volume of ship-ballast water压载水— taken in to provide ship stability—continuously moving around the world…Ships load up with ballast water and its inhabitants in coastal waters of one port and dump the ballast in another port that may be thousands of kilometers away. A single load can run to hundreds of gallons. Some larger ships take on as much as 40 million gallons. The creatures that come along tend to be in their larva free-floating stage. When discharged排出in alien waters they can mature into crabs, jellyfish水母, slugs鼻涕虫，蛞蝓, and many other forms.Since the problem involves coastal species, simply banning ballast dumps in coastal waters would, in theory, solve it. Coastal organisms in ballast water that is flushed into midocean would not survive. Such a ban has worked for North American Inland Waterway. But it would be hard to enforce it worldwide. Heating ballast water or straining it should also halt the species spread. But before any such worldwide regulations were imposed, scientists would need a clearer view of what is going on.The continuous shuffling洗牌of marine organisms has changed the biology of the sea on a global scale. It can have devastating effects as in the case of the American comb jellyfish that recently invaded the Black Sea. It has destroyed that sea’s anchovy鳀鱼fishery by eating anchovy eggs. It may soon spread to western and northern European waters.The maritime nations that created the biological ―conveyor belt‖ should support a coordinated international effort to find out what is going on and what should be done about it. (456 words)1.According to Dr. Carlton, ocean organism‟s are_______.A.being moved to new environmentsB.destroying the planetC.succumbing to the zebra musselD.developing alien characteristics2.Oceanographers海洋学家are concerned because_________.A.their knowledge of this phenomenon is limitedB.they believe the oceans are dyingC.they fear an invasion from outer-spaceD.they have identified thousands of alien webs3.According to marine ecologists, transplanted marinespecies____________.A.may upset the ecosystems of coastal watersB.are all compatible with one anotherC.can only survive in their home watersD.sometimes disrupt shipping lanes4.The identified cause of the problem is_______.A.the rapidity with which larvae matureB. a common practice of the shipping industryC. a centuries old speciesD.the world wide movement of ocean currents5.The article suggests that a solution to the problem__________.A.is unlikely to be identifiedB.must precede further researchC.is hypothetically假设地，假想地easyD.will limit global shippingText BNew …Endangered‟ List Targets Many US RiversIt is hard to think of a major natural resource or pollution issue in North America today that does not affect rivers.Farm chemical runoff残渣, industrial waste, urban storm sewers, sewage treatment, mining, logging, grazing放牧,military bases, residential and business development, hydropower水力发电,loss of wetlands. The list goes on.Legislation like the Clean Water Act and Wild and Scenic Rivers Act have provided some protection, but threats continue.The Environmental Protection Agency (EPA) reported yesterday that an assessment of 642,000 miles of rivers and streams showed 34 percent in less than good condition. In a major study of the Clean Water Act, the Natural Resources Defense Council last fall reported that poison runoff impairs损害more than 125,000 miles of rivers.More recently, the NRDC and Izaak Walton League warned that pollution and loss of wetlands—made worse by last year’s flooding—is degrading恶化the Mississippi River ecosystem.On Tuesday, the conservation group保护组织American Rivers issued its annual list of 10 ―endangered‖ and 20 ―threatened‖ rivers in 32 states, the District of Colombia, and Canada.At the top of the list is the Clarks Fork of the Yellowstone River, whereCanadian mining firms plan to build a 74-acre英亩reservoir水库，蓄水池as part of a gold mine less than three miles from Yellowstone National Park. The reservoir would hold the runoff from the sulfuric acid 硫酸used to extract gold from crushed rock.―In the event this tailings pond failed, the impact to th e greater Yellowstone ecosystem would be cataclysmic大变动的，灾难性的and the damage irreversible不可逆转的.‖ Sen. Max Baucus of Montana, chairman of the Environment and Public Works Committee, wrote to Noranda Minerals Inc., an owner of the ― New World Mine‖.Last fall, an EPA official expressed concern about the mine and its potential impact, especially the plastic-lined storage reservoir. ― I am unaware of any studies evaluating how a tailings pond尾矿池，残渣池could be maintained to ensure its structural integrity forev er,‖ said Stephen Hoffman, chief of the EPA’s Mining Waste Section. ―It is my opinion that underwater disposal of tailings at New World may present a potentially significant threat to human health and the environment.‖The results of an environmental-impact statement, now being drafted by the Forest Service and Montana Department of State Lands, could determine the mine’s future…In its recent proposal to reauthorize the Clean Water Act, the Clinton administration noted ―dramatically improved water quality since 1972,‖ when the act was passed. But it also reported that 30 percent of riverscontinue to be degraded, mainly by silt泥沙and nutrients from farm and urban runoff, combined sewer overflows, and municipal sewage城市污水. Bottom sediments沉积物are contaminated污染in more than 1,000 waterways, the administration reported in releasing its proposal in January. Between 60 and 80 percent of riparian corridors (riverbank lands) have been degraded.As with endangered species and their habitats in forests and deserts, the complexity of ecosystems is seen in rivers and the effects of development----beyond the obvious threats of industrial pollution, municipal waste, and in-stream diversions改道to slake消除the thirst of new communities in dry regions like the Southwes t…While there are many political hurdles障碍ahead, reauthorization of the Clean Water Act this year holds promise for US rivers. Rep. Norm Mineta of California, who chairs the House Committee overseeing the bill, calls it ―probably the most important env ironmental legislation this Congress will enact.‖ (553 words)6.According to the passage, the Clean Water Act______.A.has been ineffectiveB.will definitely be renewedC.has never been evaluatedD.was enacted some 30 years ago7.“Endangered” rivers are _________.A.catalogued annuallyB.less polluted than ―threatened rivers‖C.caused by floodingD.adjacent to large cities8.The “cataclysmic” event referred to in paragraph eight would be__________.A. fortuitous偶然的，意外的B. adventitious外加的，偶然的C. catastrophicD. precarious不稳定的，危险的9. The owners of the New World Mine appear to be______.A. ecologically aware of the impact of miningB. determined to construct a safe tailings pondC. indifferent to the concerns voiced by the EPAD. willing to relocate operations10. The passage conveys the impression that_______.A. Canadians are disinterested in natural resourcesB. private and public environmental groups aboundC. river banks are erodingD. the majority of US rivers are in poor conditionText CA classic series of experiments to determine the effects ofoverpopulation on communities of rats was reported in February of 1962 in an article in Scientific American. The experiments were conducted by a psychologist, John B. Calhoun and his associates. In each of these experiments, an equal number of male and female adult rats were placed in an enclosure and given an adequate supply of food, water, and other necessities. The rat populations were allowed to increase. Calhoun knew from experience approximately how many rats could live in the enclosures without experiencing stress due to overcrowding. He allowed the population to increase to approximately twice this number. Then he stabilized the population by removing offspring that were not dependent on their mothers. He and his associates then carefully observed and recorded behavior in these overpopulated communities. At the end of their experiments, Calhoun and his associates were able to conclude that overcrowding causes a breakdown in the normal social relationships among rats, a kind of social disease. The rats in the experiments did not follow the same patterns of behavior as rats would in a community without overcrowding.The females in the rat population were the most seriously affected by the high population density: They showed deviant异常的maternal behavior; they did not behave as mother rats normally do. In fact, many of the pups幼兽，幼崽, as rat babies are called, died as a result of poor maternal care. For example, mothers sometimes abandoned their pups,and, without their mothers' care, the pups died. Under normal conditions, a mother rat would not leave her pups alone to die. However, the experiments verified that in overpopulated communities, mother rats do not behave normally. Their behavior may be considered pathologically 病理上，病理学地diseased.The dominant males in the rat population were the least affected by overpopulation. Each of these strong males claimed an area of the enclosure as his own. Therefore, these individuals did not experience the overcrowding in the same way as the other rats did. The fact that the dominant males had adequate space in which to live may explain why they were not as seriously affected by overpopulation as the other rats. However, dominant males did behave pathologically at times. Their antisocial behavior consisted of attacks on weaker male,female, and immature rats. This deviant behavior showed that even though the dominant males had enough living space, they too were affected by the general overcrowding in the enclosure.Non-dominant males in the experimental rat communities also exhibited deviant social behavior. Some withdrew completely; they moved very little and ate and drank at times when the other rats were sleeping in order to avoid contact with them. Other non-dominant males were hyperactive; they were much more active than is normal, chasing other rats and fighting each other. This segment of the rat population, likeall the other parts, was affected by the overpopulation.The behavior of the non-dominant males and of the other components of the rat population has parallels in human behavior. People in densely populated areas exhibit deviant behavior similar to that of the rats in Calhoun's experiments. In large urban areas such as New York City, London, Mexican City, and Cairo, there are abandoned children. There are cruel, powerful individuals, both men and women. There are also people who withdraw and people who become hyperactive. The quantity of other forms of social pathology such as murder, rape, and robbery also frequently occur in densely populated human communities. Is the principal cause of these disorders overpopulation? Calhoun’s experiments suggest that it might be. In any case, social scientists and city planners have been influenced by the results of this series of experiments.11. Paragraph l is organized according to__________.A. reasonsB. descriptionC. examplesD. definition12．Calhoun stabilized the rat population_________.A. when it was double the number that could live in the enclosure without stressB. by removing young ratsC. at a constant number of adult rats in the enclosureD. all of the above are correct13.W hich of the following inferences CANNOT be made from theinformation inPara. 1?A. Calhoun's experiment is still considered important today.B. Overpopulation causes pathological behavior in rat populations.C. Stress does not occur in rat communities unless there is overcrowding.D. Calhoun had experimented with rats before.14. Which of the following behavior didn‟t happen in this experiment?A. All the male rats exhibited pathological behavior.B. Mother rats abandoned their pups.C. Female rats showed deviant maternal behavior.D. Mother rats left their rat babies alone.15. The main idea of the paragraph three is that __________.A. dominant males had adequate living spaceB. dominant males were not as seriously affected by overcrowding as the otherratsC. dominant males attacked weaker ratsD. the strongest males are always able to adapt to bad conditionsText DThe first mention of slavery in the statutes法令，法规of the English colonies of North America does not occur until after 1660—some forty years after the importation of the first Black people. Lest we think that existed in fact before it did in law, Oscar and Mary Handlin assure us, that the status of B lack people down to the 1660’s was that of servants. A critique批判of the Handlins’ interpretation of why legal slavery did not appear until the 1660’s suggests that assumptions about the relation between slavery and racial prejudice should be reexamined, and that explanation for the different treatment of Black slaves in North and South America should be expanded.The Handlins explain the appearance of legal slavery by arguing that, during the 1660’s, the position of white servants was improving relative to that of black servants. Thus, the Handlins contend, Black and White servants, heretofore treated alike, each attained a different status. There are, however, important objections to this argument. First, the Handlins cannot adequately demonstrate that t he White servant’s position was improving, during and after the 1660’s; several acts of the Maryland and Virginia legislatures indicate otherwise. Another flaw in the Handlins’ interpretation is their assumption that prior to the establishment of legal slavery there was no discrimination against Black people. It is true that before the 1660’s Black people were rarely called slaves. But this shouldnot overshadow evidence from the 1630’s on that points to racial discrimination without using the term slavery. Such discrimination sometimes stopped short of lifetime servitude or inherited status—the two attributes of true slavery—yet in other cases it included both. The Handlins’ argument excludes the real possibility that Black people in the English colonies were never treated as the equals of White people.The possibility has important ramifications后果，影响.If from the outset Black people were discriminated against, then legal slavery should be viewed as a reflection and an extension of racial prejudice rather than, as many historians including the Handlins have argued, the cause of prejudice. In addition, the existence of discrimination before the advent of legal slavery offers a further explanation for the harsher treatment of Black slaves in North than in South America. Freyre and Tannenbaum have rightly argued that the lack of certain traditions in North America—such as a Roman conception of slavery and a Roman Catholic emphasis on equality— explains why the treatment of Black slaves was more severe there than in the Spanish and Portuguese colonies of South America. But this cannot be the whole explanation since it is merely negative, based only on a lack of something. A more compelling令人信服的explanation is that the early and sometimes extreme racial discrimination in the English colonies helped determine the particular nature of the slavery that followed. (462 words)16. Which of the following is the most logical inference to be drawn from the passage about the effects of “several acts of the Maryland and Virginia legislatures” (Para.2) passed during and after the 1660‟s?A. The acts negatively affected the pre-1660’s position of Black as wellas of White servants.B. The acts had the effect of impairing rather than improving theposition of White servants relative to what it had been before the 1660’s.C. The acts had a different effect on the position of white servants thandid many of the acts passed during this time by the legislatures of other colonies.D. The acts, at the very least, caused the position of White servants toremain no better than it had been before the 1660’s.17. With which of the following statements regarding the status ofBlack people in the English colonies of North America before the 1660‟s would the author be LEAST likely to agree?A. Although black people were not legally considered to be slaves,they were often called slaves.B. Although subject to some discrimination, black people had a higherlegal status than they did after the 1660’s.C. Although sometimes subject to lifetime servitude, black peoplewere not legally considered to be slaves.D. Although often not treated the same as White people, black people,like many white people, possessed the legal status of servants.18. According to the passage, the Handlins have argued which of thefollowing about the relationship between racial prejudice and the institution of legal slavery in the English colonies of North America?A. Racial prejudice and the institution of slavery arose simultaneously.B. Racial prejudice most often the form of the imposition of inheritedstatus, one of the attributes of slavery.C. The source of racial prejudice was the institution of slavery.D. Because of the influence of the Roman Catholic Church, racialprejudice sometimes did not result in slavery.19. The passage suggests that the existence of a Roman conception ofslavery in Spanish and Portuguese colonies had the effect of _________.A. extending rather than causing racial prejudice in these coloniesB. hastening the legalization of slavery in these colonies.C. mitigating some of the conditions of slavery for black people in these coloniesD. delaying the introduction of slavery into the English colonies20. The author considers the explanation put forward by Freyre andTannenbaum for the treatment accorded B lack slaves in the English colonies of North America to be _____________.A. ambitious but misguidedB. valid有根据的but limitedC. popular but suspectD. anachronistic过时的，时代错误的and controversialUNIT 2Text AThe sea lay like an unbroken mirror all around the pine-girt, lonely shores of Orr’s Island. Tall, kingly spruce s wore their regal王室的crowns of cones high in air, sparkling with diamonds of clear exuded gum流出的树胶; vast old hemlocks铁杉of primeval原始的growth stood darkling in their forest shadows, their branches hung with long hoary moss久远的青苔;while feathery larches羽毛般的落叶松,turned to brilliant gold by autumn frosts, lighted up the darker shadows of the evergreens. It was one of those hazy朦胧的, calm, dissolving days of Indian summer, when everything is so quiet that the fainest kiss of the wave on the beach can be heard, and white clouds seem to faint into the blue of the sky, and soft swathing一长条bands of violet vapor make all earth look dreamy, and give to the sharp, clear-cut outlines of the northern landscape all those mysteries of light and shade which impart such tenderness to Italian scenery.The funeral was over,--- the tread鞋底的花纹/ 踏of many feet, bearing the heavy burden of two broken lives, had been to the lonely graveyard, and had come back again,--- each footstep lighter and more unconstrained不受拘束的as each one went his way from the great old tragedy of Death to the common cheerful of Life.The solemn black clock stood swaying with its eternal ―tick-tock, tick-tock,‖ in the kitchen of the brown house on Orr’s Island. There was there that sense of a stillness that can be felt,---such as settles down on a dwelling住处when any of its inmates have passed through its doors for the last time, to go whence they shall not return. The best room was shut up and darkened, with only so much light as could fall through a little heart-shaped hole in the window-shutter,---for except on solemn visits, or prayer-meetings or weddings, or funerals, that room formed no part of the daily family scenery.The kitchen was clean and ample, hearth灶台, and oven on one side, and rows of old-fashioned splint-bottomed chairs against the wall. A table scoured to snowy whiteness, and a little work-stand whereon lay the Bible, the Missionary Herald, and the Weekly Christian Mirror, before named, formed the principal furniture. One feature, however, must not be forgotten, ---a great sea-chest水手用的储物箱,which had been the companion of Zephaniah through all the countries of the earth. Old, and battered破旧的，磨损的, and unsightly难看的it looked, yet report said that there was good store within which men for the most part respect more than anything else; and, indeed it proved often when a deed of grace was to be done--- when a woman was suddenly made a widow in a coast gale大风，狂风, or a fishing-smack小渔船was run down in the fogs off the banks, leaving in some neighboring cottage a family of orphans,---in all such cases, the opening of this sea-chest was an event of good omen 预兆to the bereaved丧亲者;for Zephaniah had a large heart and a large hand, and was apt有…的倾向to take it out full of silver dollars when once it went in. So the ark of the covenant约柜could not have been looked on with more reverence崇敬than the neighbours usually showed to Captain Pennel’s sea-chest.1. The author describes Orr‟s Island in a(n)______way.A.emotionally appealing, imaginativeB.rational, logically preciseC.factually detailed, objectiveD.vague, uncertain2.According to the passage, the “best room”_____.A.has its many windows boarded upB.has had the furniture removedC.is used only on formal and ceremonious occasionsD.is the busiest room in the house3.From the description of the kitchen we can infer that thehouse belongs to people who_____.A.never have guestsB.like modern appliancesC.are probably religiousD.dislike housework4.The passage implies that_______.A.few people attended the funeralB.fishing is a secure vocationC.the island is densely populatedD.the house belonged to the deceased5.From the description of Zephaniah we can see thathe_________.A.was physically a very big manB.preferred the lonely life of a sailorC.always stayed at homeD.was frugal and saved a lotText BBasic to any understanding of Canada in the 20 years after the Second World War is the country' s impressive population growth. For every three Canadians in 1945, there were over five in 1966. In September 1966 Canada's population passed the 20 million mark. Most of this surging growth came from natural increase. The depression of the 1930s and the war had held back marriages, and the catching-up process began after 1945. The baby boom continued through the decade of the 1950s, producing a population increase of nearly fifteen percent in the five years from 1951 to 1956. This rate of increase had been exceeded only once before in Canada's history, in the decade before 1911 when the prairies were being settled. Undoubtedly, the good economic conditions of the 1950s supported a growth in the population, but the expansion also derived from a trend toward earlier marriages and an increase in the average size of families; In 1957 the Canadian birth rate stood at 28 per thousand, one of the highest in the world. After the peak year of 1957, thebirth rate in Canada began to decline. It continued falling until in 1966 it stood at the lowest level in 25 years. Partly this decline reflected the low level of births during the depression and the war, but it was also caused by changes in Canadian society. Young people were staying at school longer, more women were working; young married couples were buying automobiles or houses before starting families; rising living standards were cutting down the size of families. It appeared that Canada was once more falling in step with the trend toward smaller families that had occurred all through theWestern world since the time of the Industrial Revolution. Although the growth in Canada’s population had slowed down by 1966 (the cent), another increase in the first half of the 1960s was only nine percent), another large population wave was coming over the horizon. It would be composed of the children of the children who were born during the period of the high birth rate prior to 1957.6. What does the passage mainly discuss?A. Educational changes in Canadian society.B. Canada during the Second World War.C. Population trends in postwar Canada.D. Standards of living in Canada.7. According to the passage, when did Canada's baby boom begin?A. In the decade after 1911.B. After 1945.C. During the depression of the 1930s.D. In 1966.8. The author suggests that in Canada during the 1950s____________.A. the urban population decreased rapidlyB. fewer people marriedC. economic conditions were poorD. the birth rate was very high9. When was the birth rate in Canada at its lowest postwar level?A. 1966.B. 1957.C. 1956.D. 1951.10. The author mentions all of the following as causes of declines inpopulation growth after 1957 EXCEPT_________________.A. people being better educatedB. people getting married earlierC. better standards of livingD. couples buying houses11.I t can be inferred from the passage that before the IndustrialRevolution_______________.A. families were largerB. population statistics were unreliableC. the population grew steadilyD. economic conditions were badText CI was just a boy when my father brought me to Harlem for the first time, almost 50 years ago. We stayed at the hotel Theresa, a grand brick structure at 125th Street and Seventh avenue. Once, in the hotel restaurant, my father pointed out Joe Louis. He even got Mr. Brown, the hotel manager, to introduce me to him, a bit punchy强力的but still champ焦急as fast as I was concerned.Much has changed since then. Business and real estate are booming. Some say a new renaissance is under way. Others decry责难what they see as outside forces running roughshod肆意践踏over the old Harlem. New York meant Harlem to me, and as a young man I visited it whenever I could. But many of my old haunts are gone. The Theresa shut down in 1966. National chains that once ignored Harlem now anticipate yuppie money and want pieces of this prime Manhattan real estate. So here I am on a hot August afternoon, sitting in a Starbucks that two years ago opened a block away from the Theresa, snatching抓取，攫取at memories between sips of high-priced coffee. I am about to open up a piece of the old Harlem---the New York Amsterdam News---when a tourist。

manual for the patterns of adaptive learning scale

manual for the patterns of adaptivelearning scaleAdaptive learning is an important approach in education that aims to personalize and optimize the learning experience for individual students. One tool that is commonly used to measure the effectiveness of adaptive learning is the Patterns of Adaptive Learning Scale (PALS). This manual provides a comprehensive guide on how to use PALS effectively.Introduction to PALSThe Patterns of Adaptive Learning Scale (PALS) is a self-report instrument that assesses students' perceptions of their learning patterns and strategies in adaptive learning environments. It consists of two major sections: Patterns of Adaptive Learning (PAL) and Learning Strategies (LS).Section 1: Patterns of Adaptive Learning (PAL)This section focuses on capturing students' learning patterns in adaptive learning environments. It includes the following subscales:1. Mastery approach: This subscale assesses students' inclination to set challenging goals, persist in the face of difficulties, and actively seek opportunities to expand their knowledge and skills.2. Performance approach: This subscale measures students' motivation to perform well in order to receive recognition or praise from others.3. Performance avoidance: This subscale evaluates students' tendency to avoid tasks or activities that may expose their lack of ability or lead to failure.4. Help-seeking: This subscale examines students' willingness to seek assistance when facing challenges or difficulties.Section 2: Learning Strategies (LS)This section focuses on students' utilization of adaptive learning strategies. It consists of the following subscales:1. Rehearsal: This subscale assesses students' use of rote memorization or repetition to remember information.2. Organization: This subscale measures students' ability to categorize, summarize, and integrate information to facilitate comprehension and learning.3. Elaboration: This subscale evaluates students' capacity to elaborate or expand on information through examples, analogies, or connections to existing knowledge.4. Metacognitive self-regulation: This subscale examines students' awareness and control of their own learning process, including planning, monitoring, and evaluating their learning strategies.Using PALSTo administer PALS, distribute the questionnaire to students and instruct them to respond honestly based on their experiences in adaptive learning environments. Ensure that they understand the instructions and provide a comfortable and confidential setting to encourage candid responses.Once all the responses are collected, calculate the scores for each subscale by summing the relevant items. Higher scores indicate stronger adherence to the respective learning pattern or strategy.Interpreting PALS ResultsWhen interpreting the results, it is important to consider that PALS provides insights into students' perceptions of their learning patterns and strategies, rather than objective measures of their actual behavior. Therefore, the results should be used as a starting point for further analysis and discussions.The Patterns of Adaptive Learning Scale manual also provides guidance on how to interpret the scores, including the recommended benchmarks and comparisons that can be made with other groups or normative data.ConclusionThe Patterns of Adaptive Learning Scale (PALS) is a valuable tool for assessing students' perceptions of their learning patterns and strategies in adaptive learning environments. By understanding students' preferences and approaches to learning, educators can make informed decisions to enhance the effectiveness of adaptive learning interventions. This manual serves as a comprehensive guide to administering and interpreting PALS, enabling educators to gain valuable insights into students' adaptive learning experiences.。

朝向层序地层学的标准化

Towards the standardization of sequence stratigraphyO.Catuneanu a ,⁎,V.Abreu b ,J.P.Bhattacharya c ,M.D.Blum d ,R.W.Dalrymple e ,P.G.Eriksson f ,C.R.Fielding g ,W.L.Fisher h ,W.E.Galloway i ,M.R.Gibling j ,K.A.Giles k ,J.M.Holbrook l ,R.Jordan m ,C.G.St.C.Kendall n ,B.Macurda o ,O.J.Martinsen p ,A.D.Miall q ,J.E.Neal b ,D.Nummedal r ,L.Pomar s ,H.W.Posamentier t ,B.R.Pratt u ,J.F.Sarg v ,K.W.Shanley w ,R.J.Steel h ,A.Strasser x ,M.E.Tucker y ,C.Winker zaDepartment of Earth and Atmospheric Sciences,University of Alberta,1-26Earth Sciences Building,Edmonton,Alberta,T6G 2E3,Canada bExxonMobil Exploration Company,Houston,Texas 77060,USA cGeosciences Department,University of Houston,Houston,Texas 77204-5007,USA dDepartment of Geology and Geophysics,Louisiana State University,Baton Rouge,Louisiana 70803,USA eDepartment of Geological Sciences and Geological Engineering,Queen's University,Kingston,Ontario K7L 3N6,Canada fDepartment of Geology,University of Pretoria,0002Pretoria,South Africa gDepartment of Geosciences,University of Nebraska-Lincoln,Nebraska 68588-0340,USA hDepartment of Geological Sciences,The University of Texas at Austin,Austin,Texas 78712,USA iInstitute for Geophysics,The University of Texas at Austin,Austin,Texas 78758-4445,USA jDepartment of Earth Sciences,Dalhousie University,Halifax,Nova Scotia,B3H 4J1,Canada kInstitute of Tectonic Studies,New Mexico State University,P.O.Box 30001,Las Cruces,New Mexico 88003,USA lDepartment of Geology,The University of Texas at Arlington,Texas 76019-0049,USA mJordan Geology,Centreville,Delaware,USA nDepartment of Geological Sciences,University of South Carolina,Columbia,South Carolina 29208,USA oThe Energists,10260Westheimer,Suite 300,Houston,Texas 77042,USA pStatoilHydro Technology and New Energy,PO Box 7200,5020Bergen,Norway qDepartment of Geology,University of Toronto,Toronto,Ontario,M5S 3B1,Canada rColorado Energy Research Institute,Colorado School of Mines,Golden,Colorado 80401,USA sDepartment of Earth Sciences,Universitat de les Illes Balears,E-07071Palma de Mallorca,Spain tChevron Energy Technology Company,Houston,Texas,USA uDepartment of Geological Sciences,University of Saskatchewan,Saskatoon,Saskatchewan S7N 5E2,Canada vColorado Energy Research Institute,Colorado School of Mines,Golden,Colorado 80401,USA wStone Energy LLC,1801Broadway,Denver,Colorado 80202,USA xDepartment of Geosciences,University of Fribourg,CH-1700Fribourg,Switzerland yDepartment of Earth Sciences,Durham University,Durham DH13LE,UK zShell International E&P Inc,3737Bellaire Blvd,P.O.Box 481,Houston,Texas 77001-0481,USAa b s t r a c ta r t i c l e i n f o Article history:Received 13April 2008Accepted 13October 2008Available online 21October 2008Keywords:sequence stratigraphy stratal stacking patterns accommodation sediment supply shoreline trajectory methodology nomenclatureSequence stratigraphy emphasizes facies relationships and stratal architecture within a chronological framework.Despite its wide use,sequence stratigraphy has yet to be included in any stratigraphic code or guide.This lack of standardization re ﬂects the existence of competing approaches (or models)and confusing or even con ﬂicting terminology.Standardization of sequence stratigraphy requires the de ﬁnition of the fundamental model-independent concepts,units,bounding surfaces and work ﬂow that outline the foundation of the method.A standardized scheme needs to be suf ﬁciently broad to encompass all possible choices of approach,rather than being limited to a single approach or model.A sequence stratigraphic framework includes genetic units that result from the interplay of accommodation and sedimentation (i.e.,forced regressive,lowstand and highstand normal regressive,and transgressive),which are bounded by ‘sequence stratigraphic ’surfaces.Each genetic unit is de ﬁned by speci ﬁc stratal stacking patterns and bounding surfaces,and consists of a tract of correlatable depositional systems (i.e.,a ‘systems tract ’).The mappability of systems tracts and sequence stratigraphic surfaces depends on depositional setting and the types of data available for analysis.It is this high degree of variability in the precise expression of sequence stratigraphic units and bounding surfaces that requires the adoption of a methodology that is suf ﬁciently ﬂexible that it can accommodate the range of likely expressions.TheEarth-Science Reviews 92(2009)1–33⁎Corresponding author.E-mail address:octavian@ualberta.ca (O.Catuneanu).0012-8252/$–see front matter ©2009Elsevier B.V.All rights reserved.doi:10.1016/j.earscirev.2008.10.003Contents lists available at ScienceDirectEarth-Science Reviewsj ou r n a l h o m e pa g e :ww w.e l s e v i e r.c o m/l o c a t e /e a r s c i r e vintegration of outcrop,core,well-log and seismic data affords the optimal approach to the application ofsequence stratigraphy.Missing insights from one set of data or another may limit the‘resolution’of thesequence stratigraphic interpretation.A standardized workﬂow of sequence stratigraphic analysis requires the identiﬁcation of all genetic units andbounding surfaces that can be delineated objectively,at the selected scale of observation,within astratigraphic section.Construction of this model-independent framework of genetic units and boundingsurfaces ensures the success of the sequence stratigraphic method.Beyond this,the interpreter may makemodel-dependent choices with respect to which set of sequence stratigraphic surfaces should be elevated inimportance and be selected as sequence boundaries.In practice,the succession often dictates which set ofsurfaces are best expressed and hold the greatest utility at deﬁning sequence boundaries and quasi-chronostratigraphic units.The nomenclature of systems tracts and sequence stratigraphic surfaces is alsomodel-dependent to some extent,but a standard set of terms is recommended to facilitate communicationbetween all practitioners.©2009Elsevier B.V.All rights reserved.Contents1.Introduction:background and rationale (2)2.Data sets and objectivity of data (5)2.1.Data integration (5)2.2.Limitations of seismic data (6)2.3.Limitations of outcrop,core,and well-log data (7)2.4.Objectivity of data and inherent interpretations (8)3.Model-independent platform of sequence stratigraphy (9)3.1.Methodology (9)3.2.Base level and accommodation (10)3.3.Reference curve of base-level changes (11)3.4.Events of the base-level cycle (12)3.5.Genetic types of deposit:normal regressive,forced regressive,transgressive (14)4.Model-dependent aspects of sequence stratigraphy (15)4.1.Depositional sequences (17)4.2.Genetic stratigraphic sequences (17)4.3.Transgressive–regressive sequences (18)5.Recommendations (18)5.1.Standard workﬂow (18)5.2.Deﬁnition of sequence stratigraphy (19)5.3.Deﬁnition of a‘sequence’ (19)5.4.Parasequences (19)5.5.Genetic types of deposit:systems tracts (19)5.6.Sequence stratigraphic surfaces (20)5.7.Concept of hierarchy (21)6.Discussion:variability of the sequence stratigraphic model (22)6.1.Nonmarine settings (22)6.2.Coastal to shallow-water siliciclastic settings (24)6.3.Deep-water settings (26)6.4.Carbonate settings (26)7.Conclusions (29)Acknowledgements (29)References (29)1.Introduction:background and rationaleSequence stratigraphy is considered by many as one of the latest conceptual revolutions in the broadﬁeld of sedimentary geology (Miall,1995),revamping the methodology of stratigraphic analysis. Applications of sequence stratigraphy cover a tremendous range,from deciphering the Earth's geological record of local to global changes in paleogeography and the controls governing sedimentary processes, to improving the success of petroleum exploration and production. Multiple data sets are integrated for this purpose,and insights from several disciplines are required(Fig.1).Sequence stratigraphy is uniquely focused on analyzing changes in facies and geometric character of strata and identiﬁcation of key surfaces to determine the chronological order of basinﬁlling and erosional events.Stratal stacking patterns respond to the interplay of changes in rates of sedimentation and base level,and reﬂect combinations of depositional trends that include progradation,retrogradation,aggrada-tion and downcutting.Each stratal stacking pattern deﬁnes a particu-lar genetic type of deposit(i.e.,‘transgressive’,‘normal regressive’and ‘forced regressive’;Hunt and Tucker,1992;Posamentier and Morris, 2000;Fig.2),with a distinct geometry and facies preservation style. These deposits are generic from an environmental perspective(i.e., they can be identiﬁed in different depositional settings),and may in-clude tracts of several age-equivalent depositional systems(i.e.,systems tracts).Sequence stratigraphy can be an effective tool for correlation on both local and regional scales.The method is now commonly utilized as the modern approach to integrated stratigraphic analysis,com-bining insights from all other types of stratigraphic as well as several non-stratigraphic disciplines(Fig.1).However,it remains the only2O.Catuneanu et al./Earth-Science Reviews92(2009)1–33stratigraphic method that has no standardized stratigraphic code.Efforts have been made by both the North American Commission on Stratigraphic Nomenclature (NACSN)and the International Subcom-mission on Stratigraphic Classi ﬁcation (ISSC)with respect to standar-dizing the method of sequence stratigraphy in the North American Stratigraphic Code (herein referred to as the Code)and the International Stratigraphic Guide (herein referred to as the Guide)respectively.The ISSC Working Group on Sequence Stratigraphy submitted its ﬁnal report in 1999,without reaching a consensus regarding sequence stratigraphic nomenclature and methodology.At the same time,the long-standing NACSN committee on allostratigraphy and sequence stratigraphy tabled its efforts in 2002,concluding that it was premature to recognize formal sequence stratigraphic units in the Code.The process of standardization is hampered mainly because consensus needs to be reached between ‘schools ’that promote rather different approaches (or models)with respect to how the sequence stratigraphic method should be applied to the rock record (Figs.3and 4).The need for standardization,however,is evident from the present state of procedural and nomenclatural confusion within sequence stratigraphy (Figs.3and 4).Despite numerous debates that have promoted one model overothers,Fig.1.Sequence stratigraphy in the context of interdisciplinaryresearch.Fig.2.Genetic types of deposits:normal regressive,forced regressive,transgressive.Zigzag lines indicate lateral changes of facies within the same sedimentary bodies (e.g.,individual prograding lobes).The diagram shows the possible types of shoreline trajectory during changes (rise or fall)in base level.During a stillstand of base level (not shown),the shoreline may undergo sediment-driven progradation (normal regression,where the topset is replaced by toplap),erosional transgression,or no movement at all.However,due to the complexity of independent variables that interplay to control base-level changes,it is unlikely to maintain stillstand conditions for any extended period of time.3O.Catuneanu et al./Earth-Science Reviews 92(2009)1–33there has been no general acceptance of any single approach to sequence stratigraphic analysis.Here,we do not intend to reopen the debate about the relative merits of different approaches.Instead,we examine the points of agreement and difference between existing models,evaluate the reasons for this diversity of opinion,and conclude by identifying common ground.We then use this common ground as the basis for the de ﬁnition of a process-based work ﬂow that transcends the boundaries between individual models.After over 30years of sequence stratigraphic research and de-velopments,it is fair to conclude that each model is justi ﬁableinFig.4.Nomenclature of systems tracts and timing of sequence boundaries for the existing sequence stratigraphic models (from Catuneanu,2006).Abbreviations:LST —lowstand systems tract;TST —transgressive systems tract;HST —highstand systems tract;FSST —falling-stage systems tract;RST —regressive systems tract;T –R —transgressive –regressive;CC ⁎—correlative conformity sensu Posamentier and Allen (1999);CC ⁎⁎—correlative conformity sensu Hunt and Tucker (1992);MFS —maximum ﬂooding surface;MRS —maximum regressive surface.References for the proponents of the various sequence models are provided in Fig.3.Fig.3.Sequence stratigraphic models (from Catuneanu,2006;modi ﬁed after Donovan,2001).4O.Catuneanu et al./Earth-Science Reviews 92(2009)1–33the context in which it was proposed and may provide the optimum approach under the right circumstances.One reason for the co-existence of contrasting approaches is that each sequence strati-graphic ‘school ’is validated by the working experience of its pro-ponents on the basis of different case studies or data sets that support their methodology.Consequently,the best approach to undertaking a sequence-stratigraphic analysis of a succession (i.e.,which model is ‘best ’)may vary with the tectonic setting,depositional setting,se-diment types (siliciclastics,carbonates,evaporites),the data set available for analysis (e.g.,seismic data versus well logs or outcrop observations),and even the scale of observation.This paper aims to provide guidelines for a standard work ﬂow of sequence stratigraphic analysis.For this purpose,it is necessary to de ﬁne and separate the model-independent from the model-depen-dent aspects of sequence stratigraphy.The approach proposed herein recognizes that,beyond a standard work ﬂow,ﬂexibility needs to be retained for applying sequence stratigraphy on a case-by-case basis.For example,depending on the depositional system and the types of data available,each model-dependent set of sequence-bounding surfaces may be present or absent,mappable or cryptic,thus forcing the selection of an optimum model for the ﬁnal conceptual packaging of the strata under study into sequences.Finding the right balancebetween a model-independent work ﬂow,which can be standardized,and ﬂexibility is at the forefront of what a revised Code or Guide needs to provide to the geological community.2.Data sets and objectivity of data 2.1.Data integrationThe sequence stratigraphic method yields optimum results when information derived from multiple data sets,including seismic,outcrop,core,well log,biostratigraphic and geochemical,are integrated (Fig.1).Not all these types of data may be available in every case study,a factor which may limit the ‘resolution ’of the sequence stratigraphic model.For example,onshore ‘mature ’petroleum basins may offer the entire range of data sets,whereas offshore ‘frontier ’basins may initially be in-terpreted in stratigraphic terms only through the analysis of seismic data.Working models are re ﬁned as more data become available,as,for example,when well logs and cores are added to the subsurface seismic data base following the initial seismic stratigraphic survey.Integration of data is important because each data set contributes different insights regarding the recognition of depositional trends and stratal stacking patterns (Figs.5and 6).Notably,seismic dataprovideFig.6.Contributions of different data sets to the sequence stratigraphic interpretation (from Catuneanu,2006).Integration of insights afforded by various data sets is the key to a reliable and complete sequence stratigraphicmodel.Fig.5.Utility of different data sets for building a sequence stratigraphic framework (from Catuneanu,2006).The seismic and large-scale outcrop data provide continuous subsurface and surface information respectively.In contrast,small-scale outcrops,core,and well logs provide sparse data collected from discrete locations within the basin.5O.Catuneanu et al./Earth-Science Reviews 92(2009)1–33continuous coverage of relatively large areas at the expense of ver-tical resolution,whereas outcrops,core and well logs may provide the opportunity for more detailed studies in particular locations but within the context of a sparse and discontinuous data base.Therefore,the types of data presented in Figs.5and 6complement each other and may be calibrated against each other.Mutual calibration is im-portant because the interpretation of any type of data may involve some subjectivity.The limitations involved in interpreting any types of data need to be understood and acknowledged.2.2.Limitations of seismic dataA number of fundamental applications of sequence stratigraphy are subject to uncertainty if seismic data are not used,since lapout relationships,best observed on seismic pro ﬁles,are a key to the physical recognition of sequence stratigraphic surfaces.Systems tracts were ﬁrst de ﬁned on the basis of stratal stacking patterns interpreted from the architecture and lapout terminations of seismic re ﬂections (Vail et al.,1977;Brown and Fisher,1977).Traditionally,seismic data have not been used to de ﬁne stratigraphic units in codes or guides because the establishment of earlier formal guiding documents pre-ceded the availability of such data.Stratigraphic codes and guides need to adapt to the now widespread application of seismic stra-tigraphy and to recognize the importance of seismic data in sequence stratigraphic analyses.Seismic data afford the observation of stratal terminations (lap-outs),stratal stacking patterns on 2D pro ﬁles,and 3D visualization of stratigraphic surfaces and depositional elements in the subsurface (Posamentier,2000).However,the information provided by con-ventional exploration data (i.e.,20–40Hz)is limited by the vertical seismic resolution,which ﬁlters out the ‘details ’(i.e.,the higher fre-quency cycles)that may be present in the subsurface.The ability to resolve cycles that may be amalgamated within one single re ﬂection is improving continuously as techniques of seismic data acquisition and processing progress.The fact that seismic re ﬂection architec-ture increases in complexity as resolution improves has always been recognized (Cartwright et al.,1993).In the early days of seismic stratigraphy,the vertical seismic resolution was 20–30m or more,whereas more recent multichannel seismic data have 5m of vertical resolution or less,depending on the depth of investigation.Features such as lateral-accretion surfaces within ﬂuvial point bars,scroll bars,or tidal channels can now be seen on 2D lines,horizon slices or 3D visualization maps.The latest 3D visualization techniques allow us totake virtual tours through seismic volumes,to ‘walk ’along interpreted unconformities.Conventional seismic stratigraphy has given way to the more sedimentological insights of seismic geomorphology,which allows examination of channels or other depositional or erosional elements,or analysis of the type of sediment gravity-ﬂow deposits that ﬁll submarine canyons and other deep-water channelized or lobate systems.Despite this innovation in technology and science of stratigraphic imaging,seismic stratigraphic concepts have yet to be incorporated into stratigraphic codes or guides.Vertical seismic resolution limits the scale of observation and may constrain what can be deduced from any particular case study.In regional petroleum exploration,where the focus is on mappinghigherFig.7.Seismic line in the Gulf of Mexico showing different genetic types of deposits (forced regressive,normal regressive,transgressive)and stratigraphic surfaces that may serve as sequence boundaries according to different sequence stratigraphic models (modi ﬁed from Posamentier and Kolla,2003).Abbreviations:FR —forced regressive;LNR —lowstand normal regressive;T —transgressive;SU —subaerial unconformity;CC ⁎—correlative conformity sensu Posamentier and Allen,1999(=basal surface of forced regression);CC ⁎⁎—correlative conformity sensu Hunt and Tucker,1992;MRS —maximum regressive surface;MFS —maximum ﬂooding surface.The line displays the typical stacking patterns and stratal terminations associated with forced regression (of ﬂap,downlap,toplap,truncation),normal regression (downlap,topset),and transgression(onlap).Fig.8.Spontaneous potential (SP)log from a dominantly shallow-water succession in the Gulf of Mexico.The log illustrates the uncertainty that can affect the placement of the maximum regressive and maximum ﬂooding surfaces in the case of monotonous lithological successions that lack obvious grading trends.The same problem affects the interpretation of outcrops which expose ‘massive ’beds (no grading).In this example,the uncertainty is in the range of tens of meters.Abbreviations:FS —ﬂooding surface;MRS —maximum regressive surface;MFS —maximum ﬂooding surface.6O.Catuneanu et al./Earth-Science Reviews 92(2009)1–33rank(i.e.,larger scale)sequences and systems tracts,vertical seismic resolution is no longer an important limitation.Correlative confor-mities(Fig.4)can be mapped on the basis of observable changes in stratal stacking patterns,within the few-meter interval that corre-sponds to an individual seismic reﬂection(Fig.7).Although higher frequency units may be missed because they are amalgamated within a single reﬂection,sequence stratigraphic surfaces of higher rank can be mapped and used to construct a sequence stratigraphic framework at that particular hierarchical level.The amalgamation of high-frequency cycles within single reﬂections,as the wavelength of the cycles approaches the resolution limit of the data,is a contributing factor to the dominance of the‘third-order’frameworks in many seismic stratigraphic interpretations(Nummedal,2004).In local reservoir studies where interpretation is commonly required below the vertical seismic resolution,the higher frequency sequence stratigraphic framework may be resolved by using core and/or well logs.Such an increase in stratigraphic resolution is the norm where the focus changes from exploration to production and more data become available as a result of drilling activity.2.3.Limitations of outcrop,core,and well-log dataThe interpretation of outcrops,cores and well logs in terms of the position of various sequence stratigraphic surfaces may be affected by uncertainties that rival the vertical resolution of seismic data.For example,pinpointing the surface that is interpreted to mark the time of maximum shoreline transgression along a depositional-dip transect (i.e.,a‘maximumﬂooding surface’)within a condensed section of meters or tens of meters of shale may involve a margin of error equivalent to the thickness of the condensed section.Similarly, pinpointing the surface that is interpreted to mark the time of maxi-mum shoreline regression along a depositional-dip transect(i.e.,a ‘maximum regressive surface’)within thick and massive(‘blocky’on well logs)shallow-water sandstones is equally challenging and po-tentially subject to signiﬁcant uncertainty(Fig.8).With the exception of monotonous lithological successions that show minimal changes in grain size,outcrops,cores and well logs present the opportunity to observe vertical textural(grading)trends. Such trends can then be used to interpret the position of sequence stratigraphic surfaces whose timing depends on sediment supply. Examples include maximumﬂooding and maximum regressive surfaces in siliciclastic shallow-water settings,interpreted at the top ofﬁning-upward and coarsening-upward trends respectively.Similar textural trends may be observed on carbonate platforms,where transgressions and regressions modify the shale-to-carbonate ratio, resulting in the accumulation of‘dirtier’or‘cleaner’limestones respectively.However,this ratio may also be affected by the relative ‘health’of the carbonate factory(i.e.,the production rate of carbonate sediment),which may depend on factors other than terrigenous sediment supply.The exclusive usage of grain size for the identiﬁca-tion of maximumﬂooding and maximum regressive surfaces is, therefore,simplistic,and may involve a signiﬁcant uncertainty.In a deltaic setting,for example,autocyclic shifting of prograding lobes may cause the top-of-coarsening-upward surface(interpreted as the ‘maximum regressive surface’)to be a diachronous facies contact,with components that are much older than the end of regression.In this case,the‘maximum regressive surface’is a composite surface,which consists of multiple individual segments of different ages.Notwithstanding the potential for error in the interpretation of shallow-water successions,textural trends ofﬁning-or coarsening-upward,in this particular depositional setting,can be used to map those surfaces the timing of which depends on sediment supply.As sediment supply may vary signiﬁcantly along a coastline,such surfaces,which correspond to the end-of-regression and end-of-transgression‘events’,may be highly diachronous along strike,even within the limits of biostratigraphic resolution(Gill and Cobban,1973;Martinsen and Helland-Hansen,1995;Catuneanu et al.,1998; Posamentier and Allen,1999;Catuneanu,2006).In contrast,sequence stratigraphic surfaces that form in relation to changes in the direction of base-level shift at the coastline,and so in essence independently of sediment supply(e.g.,‘correlative conformities’in Fig.4),are more suitable for building a chronostratigraphic framework.Thesesurfaces Fig.9.Workﬂow in the correlation of well logs in a transitional marine to nonmarine setting(Upper Cretaceous,central Alberta).A.Well-log cross-section:arrows indicate coarsening-upward trends,interpreted as prograding lobes(or‘parasequences’),on the gamma-ray(GR)logs.The solid line of correlation is a transgressive wave-ravinement surface(base of transgressive marine deposits).The dotted correlation line is a facies contact at the top of delta front facies.B.Options for the correlation of the prograding lobes.The selection of the option that makes most geological sense is based on a facies model of deltaic progradation which indicates that clinoforms downlap the maximum ﬂooding surface in a basinward(i.e.,easterly)direction(C).The maximumﬂooding surface(MFS)is interpreted at the top of theﬁning-upward trends that overlie the transgressive wave-ravinement surface.C.Interpreted cross-section:the steps involved in the interpretation include(1)the identiﬁcation of prograding lobes on individual well logs(A),and(2)the correlation of these lobes between isolated data control points(well logs in this case)based on the predictions of a facies model of deltaic progradation(C).7O.Catuneanu et al./Earth-Science Reviews92(2009)1–33are potentially synchronous over larger areas than the sediment-supply-controlled surfaces,although neither of them are truly chronostratigraphic (see Catuneanu,2006,for a comprehensive discussion of the time attributes of stratigraphic surfaces).Because their timing is independent of sediment supply,the criteria employed for mapping ‘correlative conformities ’are not based on changes from coarsening-to ﬁning-upward or vice versa but rather on changes in stratal stacking patterns that are best observed on seismic lines.It is also important to note that the two ‘correlative conformities ’in Figure 4mark the start and end of forced regression (Fig.2),and therefore they bracket the period of time when there is minimal or no ﬂuvial accommodation.This means that the sediment delivered to the shoreline is coarser during forced regression than it is during normal regression (Posamentier and Morris,2000;Catuneanu,2006).Thus,the correlative conformity at the base of forced regressive deposits may be marked by an increase in average grain size,whereas the correlative conformity at the top of forced regressive deposits may correspond to a decrease in average grain size during continuedprogradation (Morris et al.,1995;Posamentier et al.,1995;Posamen-tier and Morris,2000;Catuneanu,2006).Such textural changes may provide criteria to infer the position of the two types of correlative conformities in outcrop and core studies.Additional ﬁeld criteria for the distinction between ‘normal ’and ‘forced ’regressive deposits,and implicitly for the identi ﬁcation of the ‘correlative conformities ’that separate them,have been provided by Eberli et al.,(1994),Spence and Tucker (1997),Posamentier and Morris (2000),Playton and Kerans (2002),MacNeil and Jones (2006),Bover-Arnal et al.(2008),for both carbonate and siliciclastic systems.The distinction between ‘normal ’and ‘forced ’regression is important because they are fundamentally different in terms of processes active at the time of sedimentation,as well as in terms of associated petroleum plays (e.g.,Posamentier and Morris,2000;Catuneanu,2006).2.4.Objectivity of data and inherent interpretationsAll sequence stratigraphic methodologies in Figs.3and 4are based on the study of data,whether seismic,outcrop,core,well-log or any combination thereof.At the same time,interpretations are inherent in the observation and processing of any type of data.In fact,there is an intimate relationship between observations afforded by data and interpretations.A case can be made that there is no such thing as pure ‘observation ’in geology (Rudwick,1996;Miall and Miall,2001).Practically all observations carry with them some form of interpretation,otherwise they lack context and become essentially meaningless.This is true for the observations of any kind of data,from outcrop to seismic.In the case of a sparse and discontinuous data base,such as one built by isolated outcrops,core or well logs,detailed correlationbetweenFig.10.Model-independent versus model-dependent aspects of sequence stratigraphy.The model-independent aspects form the core platform of the method that is validated by all ‘schools ’.The model-dependent aspects can be left to the discretion of the practitioner;such ﬂexibility allows one to adapt more easily to the particularities of each case study.Depending on situation,any one of the models may provide the optimum approach to the sequence stratigraphic analysis.For example,the selection of sequence boundaries may depend on depositional setting or the type of data available foranalysis.Fig.11.Basic observations and interpretations involved in the sequence stratigraphic methodology.8O.Catuneanu et al./Earth-Science Reviews 92(2009)1–33。

应用电子捕获解离质谱对蛋白质磷酸化位点的定位课件

Data-dependent CID and ECD (DD-CID-ECD)
Data Analysis
3. Analysis of Results
• Summary of phosphopeptides identified from both DD-CIDECD and NL-ECD experiments. The results indicate that phosphopeptides constituted 40–45% of the starting mixture. It should be noted that not every phosphopeptide identified by CID triggered an ECD event.
• FIG. 4. Overlap between distinct, well localized (SLoMo >19) phosphopeptides identified by ECD and CID. All 725 identifications are from paired CID/ECD events. Identifications with only one possible localization are not included.
• In conclusion, our results indicate that combined ECD and CID analysis results in high confidence phosphopeptide identifications and phosphorylation site localization. Hybrid mass spectrometers, such as the LTQ-FT used in this work, are primarily used to measure precursor ions with high mass accuracy while carrying out rapid CID (at lower resolution). We showed that there are potential advantages to using both parts of the hybrid instrument during peptide fragmentation to acquire orthogonal MS/MS data.

24考研英语卷子

24考研英语卷子As the clock ticks towards the highly competitive Graduate Entrance Examination (known as the Gaokao for postgraduate studies in China), many students are gearing up for the rigorous test that could determine their academic and professional futures. The English section of the exam, in particular, is a critical component that requires a highlevel of proficiency in the language.Understanding the Structure of the English PaperThe English section of the Gaokao typically consists of several parts, including listening, reading comprehension, vocabulary and grammar, cloze tests, and essay writing. Each part is designed to assess different aspects of a student's English language skills.Strategies for Success1. Listening Comprehension: Practice is key. Use authentic materials such as news broadcasts, podcasts, and academic lectures to improve listening skills. Take notes while listening to track the main ideas and details.2. Reading Comprehension: Read a variety of texts, including academic papers, editorials, and literature. Focus on understanding the main idea, supporting details, and the author's perspective.3. Vocabulary and Grammar: Build a strong foundation in grammar and expand your vocabulary through regular study. Use flashcards, apps, and online resources to memorize new words and their usage.4. Cloze Tests: These tests require you to fill in the blanks with the appropriate words. To excel in these, understand the context and the grammatical structure of the sentences.5. Essay Writing: The ability to construct a coherent and well-argued essay is crucial. Plan your essay before writing, ensure you have a clear introduction, body, and conclusion, and use a range of vocabulary and complex sentence structures.Time ManagementEffective time management is essential during the exam. Allocate your time wisely to each section, leaving enoughtime for careful reading and review.Mock Tests and RevisionTake as many mock tests as you can to familiarizeyourself with the exam format and timing. After each test, review your mistakes and understand why you made them toavoid repeating them.Staying MotivatedThe journey to the Gaokao can be stressful, but maintaining a positive attitude and staying motivated is important. Set realistic goals, take breaks when needed, and celebrate small victories along the way.ConclusionThe English paper in the Gaokao is a comprehensive test of your language skills. With diligent preparation, strategic study methods, and a positive mindset, you can navigate this challenging exam and pave the way for your future academic endeavors. Remember, the key is to stay focused, practice consistently, and believe in your ability to succeed.。

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GY403_Syllabus_2019-20a

GY403 CONTEMPORARY DEBATES IN HUMAN GEOGRAPHY AND URBAN STUDIES Dr. Murray Low, Department of Geography and Environment Michaelmas and Lent Terms, Wednesday 5-7pm, 32L.LG.03Course Convener: Dr Murray Low (m.m.low@) Office Hours: MT Tues 2:30-4pm, St Clements Building STC.S.512AIMS AND OBJECTIVESThis is a reading seminar course focused on recent works of relevance to critical geographical research on human geography and cities. There is so much diversity in approach and style involved in contemporary research and writing in these fields that it is not possible to teach a general overview of ‘contemporary’ developments, let alone contextualize these in (inter)disciplinary history, in ten sessions. Instead, we will read and discuss readings related to selected topics of current interest, trying to achieve some level of theoretical understanding, while having an eye to how the concepts involved can achieve some form of relevance in empirical research.Together, we focus on the dynamic interplay between research and reflection, practice and theory in the human sciences, and more specifically in human geography and urban studies. The paper that students write should help enable their broader conceptualizations of feasible research projects within the broader scope of contemporary human geography and the human/social sciences more generally.TEACHINGTwo-hour fortnightly meetings on Wed 5-7pm, MT and LTASSESSMENTA 5,000 word assessed essay that answers a question framed by the student in consultation with Dr. Low. The final essay for submission is due 5th May 2020.A 2,500 word formative essay (due 17th March 2020) on a theme related to the assessed essay.BACKGROUND READINGFor background reading on critical human geography, some good places to start would be the historiography in David Livingstone’s The Geographical Tradition: Episodes in the History of a Contested Enterprise (Blackwell, 1993), the concise summaries in Derek Gregory et. al. eds. Dictionary of Human Geography 5thEdition (Routledge, 2009), and the very useful account ofdebates and trajectories in Richard Peet’s Modern Geographical Thought (Blackwell 1998) and Tim Cresswell’s (2013) Geographic Thought: a critical introduction (Wiley-Blackwell).‘Contemporary debates’ can be traced through major geographical and urban studies journals, including Antipode, The International Journal of Urban and Regional Research, Urban Studies, Geoforum, CITY, Environment and Planning A, Environment and Planning D (Society and Space), Transactions of the Institute of British Geographers, and Annals of the Association of American Geographers. There are, for geography, annual reports on sub-fields in Progress in Human Geography. Also worth referring to for sub-disciplinary issues are S. Aitken and G. Valentine eds. Approaches to Human Geography (Sage, 2005), P. Cloke et al (2004) Practising Human Geography (Sage, 2004), Cox, Robinson and Low eds. Sage Handbook of Political Geography (Sage, 2008), Sylvia Chant ed. Handbook on Gender and Poverty (Edward Elgar, 2010), and Chari and Corbridge eds. The Development Reader (Routledge, 2008). However, it is important to think of ‘geography’ in relation to broader questions, approaches, theoretical streams and methodological approaches in the human sciences more generally. We will be taking this‘wide angle’ lens in this course, and I can recommend more specific readings during the term with specific relevance to student interests and dissertation research projects. Unusually, we shall use a text for the first few sessions of the course, and you will want to acquire at least an e-book of this for yourself. The text in question is Tim Cresswell (2013) Geographic Thought: a critical introduction. Wiley-Blackwell. The e-book is available for purchase at/WileyCDA/WileyTitle/productCd-EHEP002630.htmlOr you may find it cheaper on Amazon (or an online retailer of your choice):/Geographic-Thought-Introduction-Introductions-Geography/dp/1405169397/ref=sr_1_1?s=books&ie=UTF8&qid=1381165292&sr=1-1&keywords=cresswell+geographic+thoughtREADING OUTLINEMT Week 2: Introduction to Human Geography/ Urban StudiesIn this session we will reflect a little, in a preliminary way, on what Human Geography and Urban Studies might be, discuss various ways in which to explore their literatures, and introduce the rest of the course. We will start exploring what contemporary Human Geography might be about – or might be reacting to.MT Week 4: Post-“positivist” Human GeographiesPerhaps the most broadly known critical reaction to a geography modeled on natural science understandings of research topics and methods is the Marxist geography emerging in the 1970s and still widely influential today, particularly through the work of David Harvey. We shall consider this, alongside other important alternative modes of practicing Human Geography, namely humanism, feminism and post-modernism. The basic reading consists of Cresswell (2013), Chapters 5-9. If Stuck for time 4-8 are more important.As a supplementary reading which tries to provoke some reassessment of ‘positivism’ in geography, we have Elvin Wyly (2011) “Positively Radical” International Journal of Urban and Regional Research 35, 5 889-912.As supplementary reading we are likely to look at selected chapters from Noel Castree and Derek Gregory, eds (2007) David Harvey: a critical reader. Wiley-Blackwell.MT Week 6: Post-structuralism and other 21st Century preoccupationsIn the last 15 years or so, many of the ‘strands’ or ‘varieties’ of geography considered so far have exhibited a continuing capacity to inform human geographic research on cities and other matters. However, further developments have undeniably led to a proliferation of conceptual languages drawn from a variety of sources, particularly from (largely) French theory and philosophy, with a focus on how we see and relate the humans and objects making up the world. In particular, this has led to a series of ‘new’ ways in which the problem of relating human geography to ‘nature’ are argued and explored. Here we will complete our survey of Cresswell (2013), focusing on Chapters 10-13.As a supplementary reading, and an example of the style of some recent work, we have Nigel Thrift (2011) “Lifeworld Inc – and what to do about it” Environment and Planning D: Society and Space 29,1, pp 5-26. Tim Cresswell (2012) “Nonrepresentational theory and me: notes of an interested sceptic” Environment and Planning D: Society and Space 30, pp 96-105, may also be of interest.MT Week 8: Contemporary preoccupations –“Neo-liberalism”It is undeniable that much of the critical human geography, particularly that concerned with urban phenomena, in the last 15 years has increasingly framed itself in terms of a critique of ‘neo-liberalism.’ This has drawn on both Marxist and post-structural theory (particularly Foucault). It is quite tricky to know what to look at here, as there is so much, but each article here has its uses and interest.Neil Brenner and Nik Theodore (2002) “Cities and the Geographies of‘Actually Existing Neoliberalism.” AntipodeNeil Brenner, Jamie Peck and Nik Theodore (2011) “Variegated neoliberalization: geographies, modalities, pathways.” Global Networks 10, pp 182-222.James Ferguson and Akhil Gupta (2002) “Spatializing states: toward an ethnography of neoliberal governmentality.’ American Ethnologist 29, 4, pp 981-1002Loic Wacquant (2012) “Three Steps to a Historical Anthropology of Actually Exisiting Neoliberalism.” Social Anthropology/ Anthropologie Sociale 20, 1, pp 66-79.Clive Barnett (2010) “Publics and Markets: what’s wrong with neoliberalism?” In Susan Smith, Sallie Marston, Rachel Pain and John Paul Jones III, eds, The SAGE Handbook of Social Geographies pp 269-296.MT Week 10: Contemporary preoccupations –“Comparative Urbanism”Very much at the intersection of Human Geography and Urban Studies, there is an increasingly lively set of debates around ‘comparing’ cities in a post-colonial context. Jennifer Robinson (2002) “Global and World Cities: a view from off the map.” International Journal of Urban and Regional Research 26, 3, pp 531-554.Jennifer Robinson (2011) “Cities in a World of Cities: the comparative gesture.” International Journal of Urban and Regional Research 35, 1, pp 1-23.Colin McFarlane (2010) “The Comparative city: knowledge, learning, urbanism.” International Journal of Urban and Regional Research 34, 4, pp 725-743Kevin Ward (2010) “Towards a relational comparative approach to the study of cities.” Progress in Human Geography 34, 4, 471-487.LT Week 2: Cities as/ and “assemblage”Colin MacFarlane (2011) “the city as assemblage: dwelling and urban space” Environment and Planning D: Society and Space vol 29 pp 649-671Colin McFarlane (2011) “Assemblage and critical urbanism” City 15(2) pp 204-224.Neil Brenner, David J Madden and David Wachsmuth (2011) “Assemblage urbanism and the challenges of critical urban theory.” City 15(2) pp 225-240.Fran Tonkiss (2011) “Template urbanism” City 15(5) pp 584-588.LT Week 4: Architecture and LandscapeFrederic Jameson (1984) “The cultural logic of late capitalism” New Left Review 146, pp 53-92. (The library has access to NLR going way back but it’s a little fiddly going through the archive on that site to find older papers –https:///2016/10/jameson-cultural-logic-of-late-capitalism1.pdfIf you don’t mind a less fancy version of it, the above link should do!)Brenda Yeoh and Lily Kong (1994) “Reading landscape meanings: state constructions and lived experiences in Singapore’s Chinatown” Habitat International vol 18(4) pp 17-35Loretta Lees (2001) “Towards a critical geography of architecture” Ecumene vol 8(1) pp 51-86Jane M. Jacobs (2006) “A Geography of big things” Cultural Geographies vol 13(1) pp 1-27.Claire Mercer (2017) “Landscapes of extended ruralisation: postcolonial suburbs in Dar es Salaam” Transactions of the Institute of British Geographers vol 42(1) pp 72-83LT Week 7: Decolonising Geography (with Jayaraj Sundaresan)A. J. Barker and J. Pickerill (2919) “Doings with the land and sea: decolonizing geographies, indigeneity and enacting place-agency” Progress in Human Geography (this is a submitted paper, so as yet no volume or issue number but its available through the library search).Tariq Jazee l (2014) “Subaltern geographies: geographical knowledge and postcolonial strategy” Singapore Journal of Tropical Geography vol 35(1) pp 88-103Sarah A Radcliffe (2017) “Decolonising geographical knowledges” Transactions of the Institute of British Geographers vol 42(3) pp 329-333Gurminder K Bhambra (2014) “Postcolonial and decolonial dialogues” Postcolonial studies vol 17(2) – 115-121LT Week 9: Geo graphy and “Populisms”LT Week 11: Queer Geographies: sexualities and space。

grayscale

grayscaleGrayscale: Understanding the Art of Black and WhiteIntroduction:Grayscale is a term commonly used in the world of art and design to describe the range of shades between pure black and pure white. Unlike full color images, grayscale images only display shades of gray, making them visually simpler, yet no less impactful. Grayscale is not just a technique used in art, but also serves as a metaphor for life itself. In this document, we will explore the concept of grayscale, its significance in different fields, and how it continues to captivate and inspire creativity.1. The Artistic Power of Grayscale:Grayscale images have a unique charm that draws viewers in and evokes a wide range of emotions. By eliminating color, grayscale images shift the focus to texture, contrast, and composition. This simplification forces the viewer to interpret the image in a more nuanced way, highlighting the artist's ability to master the interplay between light and dark.Whether it is photography, painting, or digital design, grayscale allows artists to convey depth and mood in a captivating and thought-provoking manner.2. Grayscale as a Symbol of Timelessness:One of the reasons grayscale is so widely used and admired is its inherent timelessness. Black and white images have been capturing our collective imagination for over a century and continue to do so today. By stripping away color, grayscale images transcend the constraints of a specific time period, enabling them to resonate with audiences across generations. Whether it is an iconic photograph from the early 20th century or a contemporary black and white masterpiece, grayscale has the power to transcend time and remain relevant indefinitely.3. Grayscale in Film and Cinematography:The use of grayscale in film and cinematography is a powerful storytelling tool. From the early days of silent films to modern black and white cinematography, grayscale allows filmmakers to create a sense of nostalgia, highlight specific details, and convey a distinct atmosphere. By eliminating colordistractions, grayscale brings attention to the narrative, acting, and cinematography. Classic films like \。

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a rXiv:h ep-ph/61256v15Dec261Background studies for a ton-scale argon dark matter detector (ArDM)∗L.Kaufmann and A.Rubbia Institute for Particle Physics,ETH Zurich,Switzerland E-mail:lilian.kaufmann@cern.ch,andre.rubbia@cern.ch The ArDM project aims at operating a large noble liquid detector to search for direct evidence of Weakly Interacting Massive Particles (WIMP)as Dark Matter in the universe.Background sources relevant to ton-scale liquid and gaseous argon detectors,such as neutrons from detector components,muon-induced neutrons and neutrons caused by radioactivity of rock,as well as the internal 39Ar background,are studied with simulations.These background radiations are addressed with the design of an appropriate shielding as well as with diﬀerent background rejection potentialities.Among them the project relies on event topology recognition,event localization,density ionization dis-crimination and pulse shape discrimination.Background rates,energy spectra,characteristics of the background-induced nuclear recoils in liquid argon,as well as the shielding performance and rejection performance of the detector are described.1.Introduction Astronomical observations suggest that over 80%of the matter contained in the universe is Dark Matter,which presumably consists of unknown andinvisible WIMPs (Weakly Interacting Massive Particles).The most com-mon candidate is the lightest supersymmetric particle.Direct detection ex-periments aim at measuring elastic scattering of WIMPs with nuclei.The energy transferred to the nuclei is typically below 100keV.Due to this low energy range and the small cross section,such a signal is diﬃcult to measure and signal sensitivity is limited by ordinary backgrounds.Background radi-ation arises from several sources and is of diﬀerent signiﬁcance.One dom-inant background source is the contamination with radioactive elements,namely uranium and thorium chains,and potassium-40resulting in α,β2andγemissions as well as neutron production processes,of the materials used in and around the detector.Another source of neutron background in underground environments comes from interactions of cosmic muons with matter,resulting in neutron production.A third background source can arise from internal contamination of the target material,e.g.with radioac-tive isotopes.The experiment for which the present study has been carried out is ArDM[1–4],a ton-scale liquid argon detector.The technical concept of the experiment relies on the independent readout of ionization charge by LEM and of scintillation light by photo-detectors[4].This paper summa-rizes the results of Monte Carlo studies carried out to assess the impact of diﬀerent background radiation in this project.2.Neutron backgroundAn important background is neutron-induced nuclear recoils which are hardly distinguable from WIMP events.The neutrons from radioactivity arise mainly from contaminations of materials or rock by the two radioac-tive elements uranium and thorium,and their decay-chain daughters.The decay chains of238U and232Th containαdecays withαenergies of3.5 to11MeV.Theseαundergo(α,n)reactions,thereby producing neutrons with energies in the MeV range.The cross section depends on the ma-terial and on theα-energy[5].Typical yields are10−8to10−5neutrons perα.Besides(α,n)reactions,neutrons can arise from spontaneousﬁssion. The number of neutrons arising from these two processes is typically of the same order of magnitude,but depends on the material.Muon-induced neutrons arise from cosmic muon interactions with surrounding materials. Highly energetic muons are able to penetrate deep underground.Neutrons are produced by spallation or photonuclear processes,or by secondary in-teractions of muon-induced hadronic showers.The shielding of the detector optimized for natural radioactivity is less eﬃcient in this case and faster neutrons can penetrate inside the detectorﬁducial region.Shielding and de-tector components can also act as a target for muons,however the expected production rates are low.2.1.Neutrons from radioactivity in detector componentsThe ArDM detector parts consist mainly of the following materials:stainless steel,vetronite,polyethylene,borosilicate glass,ceramics and copper(see Ref.[4]for details).In general,metallic materials contain much less U/Th3 contamination,i.e.typically a few ppb.Minerals and glasses generally have higher contaminations of the order of a few hundred ppb.We have estimated the number of emitted neutrons using the data from Ref.[5].Furthermore, the emission numbers have been simulated with SOURCES4a for cross-check.The numbers obtained with the two diﬀerent approaches agree well. The biggest contribution for standard materials comes from photomultiplier tubes located on the bottom of the detector and large electron multiplier (LEM)plates located on the top of the detector,since these two parts contain glass.Low background versions of these two components should reduce the rate by about two orders of magnitude.The resulting neutron production rates and the precise assumptions for component masses and contaminations are summarized in Table1.Table 1.Assumptions for detector components and estimatedneutron production based on[5]and SOURCES simulation.Adescription of the detector geometry can be found in[2–4].Component ppb U n/yearDewar(steel)0.638021000LEM low bg.<2<402.4(80tubes)400PMT low bg.30140013(8Pillars)20E exp(−E/1.29).About2neutrons are emitted per sponta-neousﬁssion.The spectrum of neutrons coming from(α,n)reactions is more involved,since the(α,n)cross section is material-dependent.For the computation of the spectra in detector component materials,the simula-tion program SOURCES4a was used.The code was extended toαenergies above6MeV by[6].The resulting spectra for stainless steel(dewar)and Vetronite(LEM)are shown in Fig.1.4Fig.1.Simulated neutron energy spectra for the dewar(left)and LEM(right).The dotted line is the contribution from spontaneousﬁssion,the crossed line the contribution from(α,n.)reactions and the circled line is the sum of the two.2.2.Neutrons from radioactivity in rock and concreteThe minerals constituting the rock overburden in an underground labora-tory also contain small amounts of U and Th,causing neutron radiation in the same way as in the detector components.The level of the contamination strongly depends on the location and the elemental composition of the rock. Usually the U/Th contamination is on the order of a few hundred ppb.The studies described here have been carried out for the Canfranc Underground Laboratory.It is located in the Pyrenees at a depth of2450m.w.e.A con-crete layer covers the walls of the laboratory,which also aﬀects the neutron radiationﬂux.CH2is the typical material used as shield against these ambient neutrons. The number of neutrons coming from rock and concrete and reaching diﬀer-ent depths of the shielding was simulated with GEANT-4[8].The neutron ﬂux decreases by approximately one order of magnitude after every10cm of CH2at energies up to6MeV,for higher energies the suppression is slightly less.The suppression for concrete neutrons is slightly lower,expecially for higher energies.On the average,60cm of CH2reduce theﬂux of neutrons by about six orders of magnitude.2.3.Detector response to neutronsBackground neutrons interact with the detector via elastic scattering with argon nuclei.The imparted recoil energy on the nucleus caused by a neutron with energy E n and a scattering angleθis E R≃2E n M n M Ar5 Neutrons from the various sources mentioned above have been simulated with the proper energy spectrum and fully propagated through a detailed geometry of the detector with GEANT-4.As an example,the resulting argon recoil spectrum for neutrons from detector components is shown in Fig.2.Fig.2.Spectrum of argon recoils caused by neutrons from detector components.Of the neutrons entering theﬁducial volume,more than50%can be re-jected because of multiple scattering,since a WIMP would never scatter more than once within the detector active volume.The number of neu-tron scatters depends on the size of theﬁducial volume,the distance of the neutron emitting components to theﬁducial volume and on the en-ergy threshold.Assuming that a WIMP-like event is a single recoil with an energy between30keV and100keV,approximately5%of the neutrons from detector components produce WIMP-like events.The number of re-maining events per year is12for the neutrons from the dewar,800for the standard material LEM,below2for the low background LEM,480for the standard PMTs,56for the low background PMTs and19for the pillars;to be compared with3500WIMP events atσWIMP−nucleon=10−7pb.3.39Ar electron backgroundCommercially available Argon is procured by liquefaction of air and con-tains radioactive isotopes.39Ar decays viaβ-disintegration into39K with a half-life of269years and Q=565keV.The concentration of39Ar in at-mospheric argon is(7.9±0.3)·10−16g/g[7],causing a decay rate of1kHz in one ton of argon.γs from U/Th of the detector components produce an interaction rate which is about three orders of magnitude smaller.6The rejection of electron andγevents is facilitated by two means: charge/light ratio discrimination[1]and pulse shape discrimination[9]. Theﬁrst uses the fact that the ionization yield of nuclear recoils is highly quenched compared to that of electron/γ,while the scintillation yield is similar.The pulse shape analysis relies on diﬀerent populations of the fast and slow components of scintillation.In order to overcome the internal39Ar background,a combined rejection power of about108—depending on the WIMP-nucleon cross section—is required.4.ConclusionThree main background sources for the ArDM experiment—a liquid argon ton-scale detector—have been studied.Neutron radiation is the most im-portant background,since neutron events have the same signature inside the detector as WIMP events.The main neutron background comes from contaminations of detector components with radioactive elements.Neutrons from rock and concrete of the underground laboratory can be shielded by a thick enough CH2shield.The internal39Ar background is strongly sup-pressed if the light/charge ratio and the scintillation light time distribution are measured precisely enough.References1. A.Benetti et al.,Nucl.Instrum.Meth.A327(1993)2032. A.Rubbia,Talk given at APP UK2006,First Meeting of the AstroparticlePhysics Group of the IOP,Sheﬃeld(UK),May20063.L.Kaufmann and A.Rubbia,arXiv:hep-ph/0611288.4. A.Rubbia,J.Phys.Conf.Ser.39,129(2006)[arXiv:hep-ph/0510320].5.R.Heaton et al.,Nucl.Instrum.Meth.A276(1989)5296.M.J.Carson et al.,Astropart.Phys.21(2004)6677.H.H.Loosli,Earth and Planetary Science Letters,63(1983)51and“Nachweisvon39Ar in atmosph¨a rischem Argon”,PhD thesis University Bern19688.S.Agostinelli et al.[GEANT4Collaboration],Nucl.Instrum.Meth.A506,250(2003).9.M.G.Boulay and A.Hime,Astropart.Phys.25,179(2006).。