Clavis a temporal reasoning system for classification of audiovisual sequences

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CurrentsituationandIssues

Activities of stakeholders
○Partnership and Collaboration
Mutual collaboration of every stakeholders to establish sound material cycle society
ቤተ መጻሕፍቲ ባይዱ
○Citizens
・Campaign of life style change such as “my chopsticks” and “my bag”
from industrial process at business facilities and the like 9 Efficient utilization of biomass materials as Circulative Resources (CRs) 9 Construction of venous distribution network with low environmental loads
wealthy society Regionally-characteristic SMS(Spheres of sound material cycle) , Lifestyle along the concept of Mottainai, Collaboration and partnership between stakeholders, and dissemination of the 3Rs into economic activities including manufacturing
{ Promotion of Integrated Efforts toward an SMC Society and Society in Harmony with Nature

Collaborative Governance in Theory and Practice

JPART18:543–571 Collaborative Governance in Theoryand PracticeChris AnsellAlison GashUniversity of California,BerkeleyABSTRACTOver the past few decades,a new form of governance has emerged to replace adversarial and managerial modes of policy making and implementation.Collaborative governance,as it has come to be known,brings public and private stakeholders together in collective forums with public agencies to engage in consensus-oriented decision making.In this article, we conduct a meta-analytical study of the existing literature on collaborative governance with the goal of elaborating a contingency model of collaborative governance.After review-ing137cases of collaborative governance across a range of policy sectors,we identify critical variables that will inﬂuence whether or not this mode of governance will produce successful collaboration.These variables include the prior history of conﬂict or cooperation, the incentives for stakeholders to participate,power and resources imbalances,leadership, and institutional design.We also identify a series of factors that are crucial within the collaborative process itself.These factors include face-to-face dialogue,trust building,and the development of commitment and shared understanding.We found that a virtuous cycle of collaboration tends to develop when collaborative forums focus on‘‘small wins’’that deepen trust,commitment,and shared understanding.The article concludes with a discus-sion of the implications of our contingency model for practitioners and for future research on collaborative governance.Over the last two decades,a new strategy of governing called‘‘collaborative governance’’has developed.This mode of governance brings multiple stakeholders together in common forums with public agencies to engage in consensus-oriented decision making.In this article,we conduct a meta-analytical study of the existing literature on collaborative governance with the goal of elaborating a general model of collaborative governance. The ultimate goal is to develop a contingency approach to collaboration that can highlight conditions under which collaborative governance will be more or less effective as an Early versions of this article were presented at the Conference on Democratic Network Governance,Copenhagen,the Interdisciplinary Committee on Organizations at the University of California,Irvine,and the Berkeley graduate seminar Perspectives on Governance.We thank the participants of these events for their useful suggestions and Martha Feldman,in particular,for her encouragement.We also thank two anonymous reviewers for their thoughtful and useful comments.Address correspondence to the author at cansell@ or aligash@.doi:10.1093/jopart/mum032Advance Access publication on November13,2007ªThe Author2007.Published by Oxford University Press on behalf of the Journal of Public Administration Researchand Theory,Inc.All rights reserved.For permissions,please e-mail:journals.permissions@approach to policy making and public management.1In conducting this meta-analytic study,we adopted a strategy we call ‘‘successive approximation’’:we used a sample of the literature to develop a common language for analyzing collaborative governance and then successively ‘‘tested’’this language against additional cases,reﬁning and elaborating our model of collaborative governance as we evaluated additional cases.Although collaborative governance may now have a fashionable management cache´,the untidy character of the literature on collaboration reﬂects the way it has bubbled up from many local experiments,often in reaction to previous governance failures.Collabo-rative governance has emerged as a response to the failures of downstream implementation and to the high cost and politicization of regulation.It has developed as an alternative to the adversarialism of interest group pluralism and to the accountability failures of manageri-alism (especially as the authority of experts is challenged).More positively,one might argue that trends toward collaboration also arise from the growth of knowledge and in-stitutional capacity.As knowledge becomes increasingly specialized and distributed and as institutional infrastructures become more complex and interdependent,the demand for collaboration increases.The common metric for all these factors may be,as Gray (1989)has pointed out,the increasing ‘‘turbulence’’faced by policy makers and managers.Although Susskind and Cruikshank (1987),Gray (1989),and Fung and Wright (2001,2003)have suggested more general theoretical accounts of collaborative governance,much of the literature is focused on the species rather than the genus .The bulk of the collaborative governance literature is composed of single-case case studies focused on sector-speciﬁc governance issues like site-based management of schools,community po-licing,watershed councils,regulatory negotiation,collaborative planning,community health partnerships,and natural resource comanagement (the species).2Moreover,a num-ber of the most inﬂuential theoretical accounts of this phenomenon are focused on speciﬁc types of collaborative governance.Healey (1996,2003)and Innes and Booher (1999a,1999b),for example,provide foundational accounts of collaborative planning,as Freeman (1997)does for regulation and administrative law and Wondolleck and Yaffee (2000)do for natural resources management.Our goal is to build on the ﬁndings of this rich literature,but also to derive theoretical and empirical claims about the genus of collaborative governance—about the common mode of governing.DEFINING COLLABORATIVE GOVERNANCEWe deﬁne collaborative governance as follows:A governing arrangement where one or more public agencies directly engage non-state stakeholders in a collective decision-making process that is formal,consensus-oriented,and deliberative and that aims to make or implement public policy or manage publicprograms or assets.This deﬁnition stresses six important criteria:(1)the forum is initiated by public agencies or institutions,(2)participants in the forum include nonstate actors,(3)participants engage directly in decision making and are not merely ‘‘consulted’’by public agencies,(4)the 1Thomas (1995)develops a contingency perspective on public participation,though it aims more broadly and is developed from the perspective of public managers.2A smaller group of studies evaluates speciﬁc types of collaborative governance at a more aggregated level (for example,see Beierle [2000],Langbein [2002],and Leach,Pelkey,and Sabatier [2002]).Journal of Public Administration Research and Theory544Ansell and Gash Collaborative Governance in Theory and Practice545 forum is formally organized and meets collectively,(5)the forum aims to make decisionsby consensus(even if consensus is not achieved in practice),and(6)the focus of collab-oration is on public policy or public management.This is a more restrictive deﬁnition thanis sometimes found in the literature.However,the wide-ranging use of the term has,as Imperial notes,been a barrier to theory building(Imperial2005,286).Since our goal is to compare apples with apples(to the extent possible),we have deﬁned the term restrictivelyso as to increase the comparability of our cases.One critical component of the term collaborative governance is‘‘governance.’’Much research has been devoted to establishing a workable deﬁnition of governance that is bounded and falsiﬁable,yet comprehensive.For instance,Lynn,Heinrich,and Hill (2001,7)construe governance broadly as‘‘regimes of laws,rules,judicial decisions,and administrative practices that constrain,prescribe,and enable the provision of publicly supported goods and services.’’This deﬁnition provides room for traditional governmental structures as well as emerging forms of public/private decision-making bodies.Stoker,onthe other hand,argues:As a baseline deﬁnition it can be taken that governance refers to the rules and forms that guidecollective decision-making.That the focus is on decision-making in the collective impliesthat governance is not about one individual making a decision but rather about groups ofindividuals or organisations or systems of organisations making decisions(2004,3).He also suggests that among the various interpretations of the term,there is‘‘baseline agreement that governance refers to the development of governing styles in which bound-aries between and within public and private sectors have become blurred’’(Stoker1998, 17).We opt for a combined approach to conceptualize governance.We agree with Lynn, Heinrich,and Hill that governance applies to laws and rules that pertain to the provision ofpublic goods.However,we adopt Stoker’s claim that governance is also about collective decision making—and speciﬁcally about collective decision making that includes bothpublic and private actors.Collaborative governance is therefore a type of governance inwhich public and private actors work collectively in distinctive ways,using particular processes,to establish laws and rules for the provision of public goods.Although there are many forms of collaboration involving strictly nonstate actors,ourdeﬁnition stipulates a speciﬁc role for public agencies.By using the term‘‘public agency,’’our intention is to include public institutions such as bureaucracies,courts,legislatures,andother governmental bodies at the local,state,or federal level.But the typical public in-stitution among our cases is,in fact,an executive branch agency,and therefore,the term‘‘public agency’’is apt.Such public agencies may initiate collaborative forums either tofulﬁll their own purposes or to comply with a mandate,including court orders,legislation,or rules governing the allocation of federal funds.For example,the Workforce InvestmentAct of1998stipulates that all states and localities receiving federal workforce develop-ment funds must convene a workforce investment board that comprised public and privateactors in order to develop and oversee policies at the state and local level concerning job training,under-and unemployment.According to our deﬁnition,these workforce invest-ments boards are mandated to engage in collaborative governance.Although public agencies are typically the initiators or instigators of collaborative governance,our deﬁnition requires participation by nonstate stakeholders.Some scholars describe interagency coordination as collaborative governance.Although there is nothing inherently wrong with using the term in this way,much of the literature on collaborativegovernance uses this term to signal a different kind of relationship between public agencies and nonstate stakeholders.Smith (1998,61),for example,argues that collaboratives in-volve ‘‘representation by key interest groups.’’Connick and Innes (2003,180)deﬁne collaborative governance as including ‘‘representatives of all relevant interests.’’Reilly (1998,115)describes collaborative efforts as a type of problem solving that involves the ‘‘shared pursuit of government agencies and concerned citizens.’’We use the term ‘‘stakeholder’’to refer both to the participation of citizens as indi-viduals and to the participation of organized groups.For convenience,we will also here-after use the term ‘‘stakeholder’’to refer to both public agencies and nonstate stakeholders,though we believe that public agencies have a distinctive leadership role in collaborative governance.Our deﬁnition of collaborative governance also sets standards for the type of participation of nonstate stakeholders.We believe that collaborative governance is never merely consultative.3Collaboration implies two-way communication and inﬂuence be-tween agencies and stakeholders and also opportunities for stakeholders to talk with each other.Agencies and stakeholders must meet together in a deliberative and multilateral process.In other words,as described above,the process must be collective .Consultative techniques,such as stakeholder surveys or focus groups,although possibly very useful management tools,are not collaborative in the sense implied here because they do not permit two-way ﬂows of communication or multilateral deliberation.Collaboration also implies that nonstate stakeholders will have real responsibility for policy outcomes.Therefore,we impose the condition that stakeholders must be directly engaged in decision making.This criterion is implicit in much of the collaborative gov-ernance literature.Freeman (1997,22),for example,argues that stakeholders participate ‘‘in all stages of the decisionmaking process.’’The watershed partnerships studied by Leach,Pelkey,and Sabatier (2002,648)make policy and implementation decisions on a range of ongoing water management issues regarding streams,rivers,and watersheds.Ultimate authority may lie with the public agency (as with regulatory negotiation),but stakeholders must directly participate in the decision-making process.Thus,advisory committees may be a form of collaborative governance if their advice is closely linked to decision-making outcomes.In practice (and by design),however,advisory committees are often far removed from actual decision making.We impose the criteria of formal collaboration to distinguish collaborative gover-nance from more casual and conventional forms of agency-interest group interaction.For example,the term collaborative governance might be thought to describe the informal relationships that agencies and interest groups have always cultivated.Surely,interest groups and public agencies have always engaged in two-way ﬂows of inﬂuence.The difference between our deﬁnition of collaborative governance and conventional interest group inﬂuence is that the former implies an explicit and public strategy of organizing this inﬂuence.Walter and Petr (2000,495),for example,describe collaborative governance as a formal activity that ‘‘involves joint activities,joint structures and shared resources,’’and Padilla and Daigle (1998,74)prescribe the development of a ‘‘structured arrangement.’’This formal arrangement implies organization and structure.Decisions in collaborative forums are consensus oriented (Connick and Innes 2003;Seidenfeld 2000).Although public agencies may have the ultimate authority to make 3See Beierle and Long (1999)for an example of collaboration as consultation.Journal of Public Administration Research and Theory546Ansell and Gash Collaborative Governance in Theory and Practice547 a decision,the goal of collaboration is typically to achieve some degree of consensus among stakeholders.We use the term consensus oriented because collaborative forumsoften do not succeed in reaching consensus.However,the premise of meeting together ina deliberative,multilateral,and formal forum is to strive toward consensus or,at least,tostrive to discover areas of agreement.Finally,collaborative governance focuses on public policies and issues.The focuson public issues distinguishes collaborative governance from other forms of consensus decision making,such as alternative dispute resolution or transformative mediation. Although agencies may pursue dispute resolution or mediation to reduce social or politicalconﬂict,these techniques are often used to deal with strictly private conﬂicts.Moreover,public dispute resolution or mediation may be designed merely to resolve private disputes.While acknowledging the ambiguity of the boundary between public and private,we restrict the use of the term‘‘collaborative governance’’to the governance of public affairs.Our deﬁnition of collaborative governance is meant to distinguish collaborative gov-ernance from two alternative patterns of policy making:adversarialism and managerialism (Busenberg1999;Futrell2003;Williams and Matheny1995).By contrast with decisionsmade adversarially,collaborative governance is not a‘‘winner-take-all’’form of interest intermediation.In collaborative governance,stakeholders will often have an adversarial relationship to one another,but the goal is to transform adversarial relationships into more cooperative ones.In adversarial politics,groups may engage in positive-sum bargainingand develop cooperative alliances.However,this cooperation is ad hoc,and adversarial politics does not explicitly seek to transform conﬂict into cooperation.In managerialism,public agencies make decisions unilaterally or through closed de-cision processes,typically relying on agency experts to make decisions(Futrell2003; Williams and Matheny1995).Although managerial agencies may take account of stake-holder perspectives in their decision making and may even go so far as to consult directlywith stakeholders,collaborative governance requires that stakeholders be directly includedin the decision-making process.A number of synonyms for collaborative governance may cause confusion.For ex-ample,‘‘corporatism’’is certainly a form of collaborative governance as we deﬁne it. Classic deﬁnitions of corporatism(like Schmitter’s)emphasize tripartite bargaining be-tween peak associations of labor and capital and the state.Typically,these peak associa-tions have a representational monopoly in their sector(they are‘‘encompassing’’).If westart with this narrower deﬁnition of corporatism,collaborative governance is the broader term.Collaborative governance often implies the inclusion of a broader range of stake-holders than corporatism,and the stakeholders often lack a representational monopoly overtheir sector.The term‘‘associational governance’’is sometimes used to refer to the more generic mode of governing with associations,but collaborative governance may not even include formal associations.The Porte Alegre project,for example,is a form of collabo-rative governance that includes individual citizens in budgetary decision making(Fung and Wright2001).Sometimes the term‘‘policy network’’is used to describe more pluralistic forms ofstate-society cooperation.A policy network may include both public agencies and stake-holder groups.Moreover,policy networks typically imply cooperative modes of deliber-ation or decision making among actors within the network.Thus,the terms policy networkand collaborative governance can refer to similar phenomena.However,collaborative governance refers to an explicit and formal strategy of incorporating stakeholders intomultilateral and consensus-oriented decision-making processes.By contrast,the co-operation inherent in policy networks may be informal and remain largely implicit (e.g.,unacknowledged,unstated,nondesigned).Moreover,it may operate through infor-mal patterns of brokerage and shuttle diplomacy rather than through formal multilateral processes.Collaborative governance and public-private partnership can also sometimes refer to the same phenomenon.Public-private partnerships typically require collaboration to func-tion,but their goal is often to achieve coordination rather than to achieve decision-making consensus per se.A public-private partnership may simply represent an agreement between public and private actors to deliver certain services or perform certain tasks.Collective decision making is therefore secondary to the deﬁnition of public-private partnership.By contrast,the institutionalization of a collective decision-making process is central to the deﬁnition of collaborative governance.Finally,a range of terms are often used interchangeably with collaborative gover-nance.Such terms include participatory management,interactive policy making,stake-holder governance,and collaborative management.We prefer the term governance to management because it is broader and encompasses various aspects of the governing process,including planning,policy making,and management.The term collaborative is also more indicative of the deliberative and consensus-oriented approach that we contrast with adversarialism or managerialism than terms like participatory or interactive.A MODEL OF COLLABORATIVE GOVERNANCEArmed with a working deﬁnition of collaborative governance,we collected a wide range of case studies from the literature.We did this in the typical fashion:we systematically reviewed journals across a wide range of disciplines,including specialist journals in public health,education,social welfare,international relations,etc.We also conducted key word electronic searches using a wide variety of search terms,including those described above and many more (e.g.,‘‘comanagement,’’‘‘public participation,’’‘‘alternative dispute res-olution’’).Of course,we also followed up on the literature cited in the cases we discovered.Ultimately,our model is built on an analysis of 137cases.Although international in scope,our search was restricted to literature in English,and thus,American cases are overrepre-sented.Even a cursory examination of our cases also suggests that natural resource man-agement cases are overrepresented.This is not due to any sampling bias on our part but rather reﬂects the importance of collaborative strategies for managing contentious local resource disputes.Most of the studies we reviewed were case studies of an attempt to implement collaborative governance in a particular sector.As you might imagine,the universe of cases we collected was quite diverse and the cases differed in quality,methodology,and intent.Although our deﬁnition was restrictive so as to facilitate comparison of apples with apples,representing this diversity was also one of our goals.We perceived experiments with collaborative governance bubbling up in many different policy sectors,with little sense that they were engaged in a similar governance strategy.Surely,we felt,these diverse experiments could learn from each other.Yet this diversity proved a challenge.Our original intention to treat these cases as a large-N data set subject to quasi-experimental statistical evaluation was not successful.Since it is useful for both scholarsJournal of Public Administration Research and Theory548Ansell and Gash Collaborative Governance in Theory and Practice549 and practitioners to understand how we arrived at our conclusions,we brieﬂy report on the problems we encountered in conducting our meta-analysis.Early attempts at systematic coding were frustrating,and we soon developed an understanding of our dilemma.Although scholars studying collaborative governancehad already made some important theoretical statements,the language used to describewhat was happening was far from standardized.We found ourselves groping toﬁnda common language of description and evaluation even as we were trying to‘‘code’’studies.Add to this challenge a severe problem of‘‘missing data’’—a reﬂection of thehighly varied motivations of the researchers—and we concluded that a quasi-experimental approach was ill advised.Ultimately,we moved toward a meta-analytic strategy that wecall successive approximation.We selected a subset of our cases and used them to developa common‘‘model’’of collaborative governance.4We then randomly selected additional subsets of case studies.The second subset was used to‘‘test’’the model developed in theﬁrst round and then to further‘‘reﬁne’’the model.A third sample of cases was used to testthe second-round model,and so on.The appendix provides a list of the studies evaluated ineach of four successive rounds of evaluation.Successive approximation has the advantage of both reﬁning the conceptual modelwhile providing some of the evaluative‘‘discipline’’of a quasi-experimental study.How-ever,we are under no illusion that this process yielded‘‘the one’’model of collaborative governance.There was a large element of art involved in both specifying and evaluatingour model.As we proceeded,we were overwhelmed by the complexity of the collaborative process.Variables and causal relationships proliferated beyond what we felt would ulti-mately be useful for policy makers and practitioners.Therefore,our model representsa conscious attempt to simplify as much as possible the representation of key variablesand their relationships.This goal of simpliﬁcation led us to stress common and frequentﬁndings across cases.This approach strengthens the generality of ourﬁndings but dis-counts less universal or frequently mentionedﬁndings from the literature.Toward the endof our analysis,we were ourselves in disagreement about how to represent key relations.We used theﬁnal round of case analysis to settle these differences.One other important clariﬁcation needs to be made before we introduce ourﬁndings.Our survey of the cases quickly disabused us of the notion that we could use our analysis to answer the question:‘‘Is collaborative governance more effective than adversarial or managerial governance?’’Very few of the studies we reviewed actually evaluated gover-nance outcomes.This is not to say that the comparison between collaborative,adversarial,and managerial governance is not relevant to these studies.Experiments with collaborative governance were typically driven by earlier failures with adversarial or managerial approaches.But systematic comparisons were rarely explicitly made.What most studiesdid try to do was understand the conditions under which stakeholders acted collaboratively.Did they engage in good faith negotiation?Did they pursue mutual gains?Did they achieve consensus?Were they satisﬁed with the process?In other words,most studies in the collaborative governance literature evaluate‘‘process outcomes’’rather than policy or management outcomes.Figure1provides a visual representation of our centralﬁndings.The model has fourbroad variables—starting conditions,institutional design,leadership,and collaborative4To avoid recreating the wheel,ourﬁrst subset was not randomly selected but included many of the most prominent theoretical statements about collaborative governance.process.Each of these broad variables can be disaggregated into more ﬁne-grained vari-ables.Collaborative process variables are treated as the core of our model,with starting conditions,institutional design,and leadership variables represented as either critical contributions to or context for the collaborative process.Starting conditions set the basic level of trust,conﬂict,and social capital that become resources or liabilities during col-laboration.Institutional design sets the basic ground rules under which collaboration takes place.And,leadership provides essential mediation and facilitation for the collaborative process.The collaborative process itself is highly iterative and nonlinear,and thus,we represent it (with considerable simpliﬁcation)as a cycle.The remainder of the article describes each of these variables in more detail and draws out their implications for a contingency model of collaborative governance.STARTING CONDITIONSThe literature is clear that conditions present at the outset of collaboration can either facilitate or discourage cooperation among stakeholders and between agencies and stake-holders.Imagine two very different starting points.In one,the stakeholders have a history of bitter division over some emotionally charged local issue and have come to regard each other as unscrupulous enemies.In the other,the stakeholders have a shared vision for what they would like to achieve through collaboration and a history of past cooperation and mutual respect.In both cases,collaboration may be difﬁcult,but the ﬁrst case must over-come problems of distrust,disrespect,and outright antagonism.We narrowed the critical starting conditions down to three broad variables:imbalances between the resources orFigure 1A Model of Collaborative GovernanceJournal of Public Administration Research and Theory550。

专题05 阅读理解D篇(2024年新课标I卷) (专家评价+三年真题+满分策略+多维变式) 原卷版

《2024年高考英语新课标卷真题深度解析与考后提升》专题05阅读理解D篇（新课标I卷）原卷版(专家评价+全文翻译+三年真题+词汇变式+满分策略+话题变式)目录一、原题呈现P2二、答案解析P3三、专家评价P3四、全文翻译P3五、词汇变式P4(一)考纲词汇词形转换P4(二)考纲词汇识词知意P4(三)高频短语积少成多P5(四)阅读理解单句填空变式P5(五)长难句分析P6六、三年真题P7(一)2023年新课标I卷阅读理解D篇P7(二)2022年新课标I卷阅读理解D篇P8(三)2021年新课标I卷阅读理解D篇P9七、满分策略（阅读理解说明文）P10八、阅读理解变式P12 变式一：生物多样性研究、发现、进展6篇P12变式二：阅读理解D篇35题变式（科普研究建议类）6篇P20一原题呈现阅读理解D篇关键词: 说明文;人与社会;社会科学研究方法研究;生物多样性; 科学探究精神;科学素养In the race to document the species on Earth before they go extinct, researchers and citizen scientists have collected billions of records. Today, most records of biodiversity are often in the form of photos, videos, and other digital records. Though they are useful for detecting shifts in the number and variety of species in an area, a new Stanford study has found that this type of record is not perfect.“With the rise of technology it is easy for people to make observation s of different species with the aid of a mobile application,” said Barnabas Daru, who is lead author of the study and assistant professor of biology in the Stanford School of Humanities and Sciences. “These observations now outnumber the primary data that comes from physical specimens(标本), and since we are increasingly using observational data to investigate how species are responding to global change, I wanted to know: Are they usable?”Using a global dataset of 1.9 billion records of plants, insects, birds, and animals, Daru and his team tested how well these data represent actual global biodiversity patterns.“We were particularly interested in exploring the aspects of sampling that tend to bias (使有偏差) data, like the greater likelihood of a citizen scientist to take a picture of a flowering plant instead of the grass right next to it,” said Daru.Their study revealed that the large number of observation-only records did not lead to better global coverage. Moreover, these data are biased and favor certain regions, time periods, and species. This makes sense because the people who get observational biodiversity data on mobile devices are often citizen scientists recording their encounters with species in areas nearby. These data are also biased toward certain species with attractive or eye-catching features.What can we do with the imperfect datasets of biodiversity?“Quite a lot,” Daru explained. “Biodiversity apps can use our study results to inform users of oversampled areas and lead them to places – and even species – that are not w ell-sampled. To improve the quality of observational data, biodiversity apps can also encourage users to have an expert confirm the identification of their uploaded image.”32. What do we know about the records of species collected now?A. They are becoming outdated.B. They are mostly in electronic form.C. They are limited in number.D. They are used for public exhibition.33. What does Daru’s study focus on?A. Threatened species.B. Physical specimens.C. Observational data.D. Mobile applications.34. What has led to the biases according to the study?A. Mistakes in data analysis.B. Poor quality of uploaded pictures.C. Improper way of sampling.D. Unreliable data collection devices.35. What is Daru’s suggestion for biodiversity apps?A. Review data from certain areas.B. Hire experts to check the records.C. Confirm the identity of the users.D. Give guidance to citizen scientists.二答案解析三专家评价考查关键能力，促进思维品质发展2024年高考英语全国卷继续加强内容和形式创新，优化试题设问角度和方式，增强试题的开放性和灵活性，引导学生进行独立思考和判断，培养逻辑思维能力、批判思维能力和创新思维能力。

reason managing the risks of organizational accidents

Bankruptcy
Protection
High hazard ventures Low hazard ventures
Catastrophe
Production
The production-protection tension creates some pathologies
Trading off improved defences for increased production. Keeping your eye on the wrong ball. Attempting too much with too little: the ‘can-do’ syndrome. Believing that past non-events predict future non-events (forgetting to be afraid).
The context:
• • • • • • STS-107 was a low-orbit, low-priority science flight. All 100+ prior flights had sustained foam damage. In 22 years all but one had landed safely. The Challenger tragedy had other causes. Strong schedule pressure from Feb 19 2004 deadline. Engineering concerns not really heard during mission.
Defenses Losses Hazards
Defense functions as intended?

2024年度2024年考研英语一完形填空详解

Trend prediction
In the future, cloze tests may place more emphasis on assessing the comprehensive language proficiency of candidates, including the depth and breadth of vocabulary, accuracy and flexibility of grammar, and comprehension and mastery of discourse.
skills
Synonym analysis
2024/3/23
Distinguish the subtle differences between synonyms and choose appropriate vocabulary based on the context.
Application of antonyms
• Problem solving technique: First, read the entire text thoroughly to understand the main idea of the article; Analyze sentence by sentence and choose the best answer based on context and logical relationships; Finally, reread the entire text and check if the answers are reasonable.
2024/3/23
12
Common sentence structure recognition and conversion methods

英语哲学思想解读50题

英语哲学思想解读50题1. The statement "All is flux" was proposed by _____.A. PlatoB. AristotleC. HeraclitusD. Socrates答案：C。

本题考查古希腊哲学思想家的观点。

赫拉克利特提出了“万物皆流”的观点。

选项A 柏拉图强调理念论；选项B 亚里士多德注重实体和形式；选项D 苏格拉底主张通过对话和反思来寻求真理。

2. "Know thyself" is a famous saying from _____.A. ThalesB. PythagorasC. DemocritusD. Socrates答案：D。

此题考查古希腊哲学家的名言。

“认识你自己”是苏格拉底的名言。

选项A 泰勒斯主要研究自然哲学；选项B 毕达哥拉斯以数学和神秘主义著称；选项C 德谟克利特提出了原子论。

3. Which philosopher believed that the world is composed of water?A. AnaximenesB. AnaximanderC. ThalesD. Heraclitus答案：C。

本题考查古希腊哲学家对世界构成的看法。

泰勒斯认为世界是由水组成的。

选项A 阿那克西美尼认为是气；选项B 阿那克西曼德认为是无定；选项D 赫拉克利特提出万物皆流。

4. The idea of the "Forms" was put forward by _____.A. PlatoB. AristotleC. EpicurusD. Stoics答案：A。

这道题考查古希腊哲学中的概念。

柏拉图提出了“理念论”，即“形式”。

选项B 亚里士多德对其进行了批判和发展；选项C 伊壁鸠鲁主张快乐主义；选项D 斯多葛学派强调道德和命运。

5. Who claimed that "The unexamined life is not worth living"?A. PlatoB. AristotleC. SocratesD. Epicurus答案：C。

CLUE-s简介

IntroductionSpatial models of land use change are important tools to analyse the possible trajectories of land use change in the near future. The results of land use models are important to evaluate policy options and assess the impact of land use change on natural and socio-economic conditions.The Conversion of Land Use and its Effects modeling framework (CLUE) (Veldkamp and Fresco, 1996; Verburg et al., 1999) was developed to simulate land use change using empirically quantified relations between land use and its driving factors in combination with dynamic modeling of competition between land use types. The model was developed for the national and continental level and applications for Central America, Ecuador, China and Java, Indonesia are available. For study areas with such a large extent the spatial resolution for analysis was coarse and, as a result, each land use is represented by assigning the relative cover of each land use type to the pixels.Land use data for study areas with a relatively small spatial extent is often based on land use maps or remote sensing images that denote land use types respectively by homogeneous polygons or classified pixels. This results in only one dominant land use type occupying one unit of analysis. Because of the differences in data representation and other features that are typical for regional applications, the CLUE model can not directly be applied at the regional scale. Therefore the modelling approach has been modified and is now called CLUE-S (the Conversion of Land Use and its Effects at Small regional extent). CLUE-S is specifically developed for the spatially explicit simulation of land use change based on an empirical analysis of location suitability combined with the dynamic simulation of competition and interactions between the spatial and temporal dynamics of land use systems.More information on the development of the CLUE-S model can be found in Verburg et al. (2002) and Verburg and Veldkamp (2003).。

外刊每日精读 Clause for thought

外刊每日精读 | Clause for thought文章脉络【1】新式解码器首次让人们可以通过非入侵方式读懂思想。

【2】最新的人工智能技术终于将读心术带入了现实世界，但有些硬性限制。

【3】解码器解读大脑活动的过程。

【4】大约有一半时间，文本与原词的意思非常接近，有时甚至完全吻合。

【5】解码器能够利用大脑活动准确描述其中的一些内容。

【6】科学家们认为非入侵性读心术是一种真正的飞跃，但也在努力减轻人们对这种新技术的担忧。

【7】大阪大学大脑活动视觉图像重构的先驱西本真司教授认为这项重要的发现，可以为脑机接口的发展奠定基础。

经济学人原文Clause for thought: first non-invasive way to read minds as AI turns brain activity into text【1】An AI-based decoder that can translate brain activity into a stream of text has been developed, in a breakthrough that allows thoughts to be read non-invasively for the first time. The decoder could reconstruct speech with uncanny accuracy while people listened to a story – or even silently imagined one – using only fMRI scan data. Previous language decoding systems have required surgical implants, and the latest advance raises the prospect of new ways to restore speech in patients strugglingto communicate as a result of stroke or motor neurone disease. Dr Alexander Huth, a neuroscientist who led the work at the University of Texas at Austin, said: “We were kind of shocked that it works as well as it does. I’ve been working on thisfor 15years … so it was shocking and exciting when it finally did work.”【2】Mind-reading has traditionally been the preserve of sci-fi, in characters such as the X-Men’s Jean Grey, but the latest AI technology has finally taken the concept into the real world. This decoder’s achievement overcomesa fundamental limitation of fMRI: while the technique can map brain activity toa specific location with incredibly high resolution, there is an inherent time lag, which makes tracking activity in real time impossible. The lag exists because fMRI scans measure the blood-flow response to brain activity, which peaks and returnsto baseline over about 10 seconds, meaning even the most powerful scanner cannot improve on this. “It’s this noisy,sluggish proxy for neural activity,” said Huth. This hard limit has hampered the ability to interpret brain activity in response to natural speech because it gives a “mishmash of information” spread over a few seconds.【3】However, the advent of large language models – the kind ofAI underpinning OpenAI’s ChatGPT – provided a new way in. These models are able to represent, in numbers, the semantic meaning of speech, allowing the scientists to look at which patterns of neuronal activity corresponded to strings of words with a particular meaning rather than attempting to read out activity word byword. The learning process was intensive: three volunteers were required to lie ina scanner for 16 hours each, listening to podcasts. The decoder was trained to match brain activity to meaning using the large language model GPT-1, a precursor to ChatGPT. Later, the same participants were scanned listening to a new storyor imagining telling a story and the decoder was used to generate text from brain activity alone.【4】About half the time, the text closely – and sometimes precisely– matched the intended meanings of the original words. “Our system works at the level ofideas, semantics, meaning,” said Huth. “This is the reason why what we get out is not the exact words, it’s the gist.” For instance, when a participant was played the words: “I don’t have my driver’s licence yet,” the decoder translated as: “She has not even started to learn to drive yet.”【5】In another case, the words: “I didn’t know whether to scream, cry or run away. Instead, I said: ‘Leave me alone!’” was decoded as: “Started to scream and cry, and then she just said: ‘I told you to leave me alone.’” The participants were also askedto watch four short, silent videos while in the scanner, and the decoder was able to use their brain activity to accurately describe some of the content, the paper in Nature Neuroscience reported.【6】“For a non -invasive method, this is a real leap forward compared to what’s been done before, which is typically single words or short sentences,” Huth said. Jerry Tang, a doctoral student at the University of Texas at Austin and co-author, said: “We take very seriously the concerns that it could be used for bad purposes, and have worked to avoid that. “We want to make sure people only use these typesof technologies when they want to and that it helps them.”【7】Prof Shinji Nishimoto of Osaka University, whohas pioneered the reconstruction of visual images from brain activity, described the paper as a “significant advance”. He said: “This is a non-trivial finding and can be a basis for the development of brain-computer interfaces.” The team now hope to assess whether the technique could be applied to other, more portable brain-imaging systems, such as functional near-infrared spectroscopy (fNIRS).。

A Temporal Reasoning System for Diagnosis and Therapy Planning(IJITCS-V7-N12-3)

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Copyright © 2015 MECS
I.J. Information Technology and Computer Science, 2015, 12, 23-29
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A Temporal Reasoning System for Diagnosis and Therapy Planning
A Temporal Reasoning System for Diagnosis and Therapy Planning
Akash Rajak
Krishna Institute of Engineering and Technology, Ghaziabad, 201 206, India Email: akashrajak@ Abstract—The research is based on the designing of Clinical Temporal Mediator for medical domain. The Clinical Temporal Mediator incorporates the concept of artificial intelligence for performing temporal reasoning tasks. The designing of reasoning system involves the implementation of various mathematical models of insulin-glucose metabolism. The reasoning system consists of three subsystems: Nuti-Diet subsystem, Insulin-Glucose subsystem and Therapy Planner and Diagnosis subsystem. The paper discusses about the designing of TPD subsystems. The temporal mediator perform diagnosis on patient’s time oriented database and also suggest therapy planning for diabetes mellitus patient. Index Terms—Artificial intelligence, temporal mediator, temporal reasoning, temporal maintenance, diabetes mellitus. I. INTRODUCTION The Clinical Temporal Mediator (CTM) integrates the tasks of temporal reasoning and temporal maintenance. The tasks of temporal reasoning and temporal maintenance are performed by CTM reasoning system and CTM maintenance system respectively [1,2,3,4,5]. The CTM reasoning system consists of three subsystems: ND (Nutri-Diet), IG (Insulin-Glucose) and TPD (Therapy and Diagnosis). The ND defines various states (meal and exercise) for achieving open-loop insulin delivery. The IG implements the states by utilizing various models of IG metabolism (adapted from [15,17,10]). The interval based temporal abstraction (temporal patterns) obtained from IG is passed to the Therapy Planner and Diagnosis (TPD) subsystem. The temporal reasoning is based on the blood glucose episodes encountered during the 24hrs of blood glucose cycle. The TPD subsystem performs the diagnosis if the blood glucose concentration shows an unexpected behavior. The behavior is based on various bands range. Depending on the diagnosis the subsystem also plans the therapy based on meal intakes, insulin injections and physical exercises. By adopting the new therapy the patient may refashion his/her blood glucose profile to normoglycemia level. The 24hrs blood glucose profile of patients can be modeled as set of blood glucose temporal patterns.

英语专四练习sublist 3 exercise with keys

Sublist 3alternative circumstances comments compensation components consent considerable constant constraints contribution convention coordination core corporate corresponding criteria deduction demonstrate document dominant emphasis ensure excluded framework fundsillustrated immigration implies initial instance interaction justification layer link location maximum minorities negative outcomes partnership philosophy physical proportion published reaction registered reliance removed scheme sequencesex shift specified sufficient tasktechnical techniques technology validity volumeExercise 1alternative task document minor schemeinteract fund considerable core proportion1. He donated $50 to a _______________ to help victims of the fire. fund2. International oil and cocoa prices have _______________ impact on the economy of Cameroon. considerable3. I have to go to my lawyer's to sign some _______________ relating to the sale of our house. documents4. His injuries were relatively _______________, so he was released from the hospital within a couple of hours of being admitted. minor5. The animal with the largest brain in _______________ to its size is the ant. proportion6. Songs and story books are a wonderful way for parents to _______________ with their children. interact7. One of the most important _______________ in learning a foreign language is to get over one's fear of making mistakes. tasks8. The company that I work at has a _______________ to increase its sales without increasing its costs. scheme9. Faced with worsening health, and a doctor that didn't seem able to help him, Craig decided to try _______________ medicine. alternative10. Stars can exist only as long as energy continues to move from their _______________ to their surfaces. cores11. The _______________ of women in the teaching profession is traditionally much higher than that of men. proportion12. The _______________ of the problem is his inability to work with others. core13. She is responsible for the majority of administrative _______________ to be done in the office. tasks14. Women walking alone late at night in large cities are at _______________ risk in this country. considerable15. In the combustion process, air, fuel, and heat _______________ to cause burning.interact16. She tried taking pills to lose weight as an _______________ to regular exercise, but had little success. alternative17. He was refused a visa because he didn't have the proper _______________. documents18. She had a _______________ role in a Batman movie before starring in her own film. minor19. She was hired through an employment program _______________ by the federal government. funded20. I don't think the government's _______________ to reduce unemployment is going to work. schemeExercise 2circumstance justify negate dominate publish technical corporate illustrate constant sequence1. The professor wrote a number of sentences on the board _______________ the similarities in grammar between the two languages. illustrating2. By lying to me about this, you have totally _______________ all the trust we had built up. negated3. I can't stand this _______________ rain. We've got to go somewhere sunny for our holidays. constant4. The Americans have _______________ Olympic basketball for many years. dominated5. Can you remember the _______________ of events leading up to the murder? sequence6. You are going to have to _______________ your decision to management because right now they are a little confused about this. justify7. Police are talking to a number of people in order to get more information about the _______________ in which the murder occurred. circumstances8. Frank is a writer of detective novels, and has _______________ over 10 best-sellers. published9. Our hockey team is looking for a _______________ sponsor to help us with costs. corporate10. Whenever you read a scientific or _______________ text in English, you will probably encounter many words you do not know. technical11. A car travelling at a _______________ speed of 100 kilometres per hour would take more than 48 million years to reach the nearest star. constant12. In the 1530s, a printing press was set up in Mexico City, and the country's first newspaper was _______________ there in 1541. published13. Racist comments against others are totally unacceptable, no matter what the _______________. circumstances14. A proper essay _______________ its ideas clearly and effectively. illustrates15. We feel that animal testing should be reduced to a minimum and carefully _______________ in each case. justified16. The increase in tax revenues has been _______________ by rising costs for the public health system. negated17. Top _______________ executives are meeting today to urge the American government to lower taxes. corporate18. The Book of Genesis in the Bible deals with the _______________ of creation, as seen by the Christian religion. sequence19. All _______________ questions should be directed to the staff at the computer help desk. technical20. For centuries, Korea was _______________ by its larger and more aggressive neighbours. dominatedExercise 3emphasis immigrate constrain technique react correspond outcome layer sex comment1. His family _______________ to Australia because economic conditions were so poor in their homeland. immigrated2. An active _______________ life has been shown to be an important part of a happy marriage. sex3. The growth of our company has been seriously _______________ by the poor state of the economy. constrained4. This ESL program puts a lot of _______________ on speaking and listening skills. emphasis5. Her tennis _______________ has improved a lot since she began taking private lessons. technique6. The _______________ he received after his presentation were highly favourable. comments7. She made a delicious cake that had chocolate ice cream on one _______________, and vanilla ice cream on another. layer8. The only _______________ that I can see of cutting the education budget is that our children will suffer. outcome9. You shouldn't mix chemicals together in science class unless you know how they will _______________. react10. I _______________ regularly with my counterpart in the head office in Toronto. correspond11. Tran is actually a dentist, but he could only find work as a janitor when he _______________ to this country. immigrated12. There are three main patterns to family life in Guyana, and they _______________ generally to class or ethnic groupings. correspond13. _______________ by its island site, Montreal is a compact city of apartments and renters. constrained14. In his efforts to modernize Yugoslavia, Josip Tito placed strong _______________ on education, rebuilding schools and libraries, and retraining teachers. emphasis15. The book has a whole _______________ of meaning that you may not get the first time you read it. layer16. The _______________ on my son's report card suggested that he could do much better in school if he made a bit more effort. comments17. The _______________ of these tests should tell us whether or not you need an operation. outcome18. She teaches a number of relaxation _______________ to help patients deal with the pain of their illness. techniques19. AIDS is often transmitted through unprotected _______________. sex20. Studies have shown that babies in the womb will _______________ to sudden loud noises or bright lights that are flashed on the mother's belly. reactExercise 4partner criterion shift ensure registerimply technology contribute compensate link1. The _______________ between smoking and cancer is too strong to ignore. link2. Much of the modern _______________ used today in wristwatches was developed in Switzerland. technology3. He _______________ a lot of time and money to helping people with AIDS. contributes4. You'd better _______________ that everything the salesman promises is written into the contract. ensure5. The grizzly bear's amazing sense of smell helps _______________ for its poor eyesight. compensate6. Over time, the world's human population has _______________ from rural to urban areas. shifted7. My golf _______________ is really slow, so we had to let a number of people play through. partner8. She didn't say she wanted to break up, but she certainly seemed to _______________ it when she said that it might be good for us to see other people. imply9. Students in our program will be graded according to the _______________ described in the course outline. criteria10. You'd better _______________ for the course pretty soon before it fills up. register AWL Sublist 3 - Exercise 4bMatching exercise11. Success or failure in learning a language will be determined by what you yourself _______________ to the process. contribute12. In the 1980s and 90s, Thailand _______________ its emphasis from agricultural to industrial production. shifted13. When the scientist noted that thousands of planets in our galaxy have the necessary conditions to support life, he seemed to be _______________ that he himself believes that life does indeed exist on other planets. implying14. The university's ESL website has a number of _______________ to some grammar and vocabulary development sites. links15. In Mongolia, weddings consist of a formal signing of the marriage _______________ at county headquarters, followed by a family feast. register16. Please _______________ that you turn off all the lights when you leave. ensure17. The sole _______________ which is considered for the position is education. We don't need people with previous experience, because we want them to learn and use our system. criterion18. Sometimes a less talented athlete can _______________ for his lack of ability by practisingmore. compensate19. Computer _______________ is becoming an increasingly essential part of the modern learning process. technology20. Turkmenistan is looking for foreign _______________ to help modernize its industries. partnersExercise 5locate exclude initial specify relydeduce valid philosophy convene component1. It is important to learn a process which will help you to _______________ the meaning of new vocabulary from context. deduce2. The United Nations has _______________ a special meeting to deal with the conflict in the Middle East. convened3. We had a few _______________ problems that were soon worked out. initial4. Police are trying to _______________ a little girl who got separated from her parents while shopping. locate5. You must have a _______________ reason if you want to reschedule your test. valid6. Problem solving is a major _______________ of many science courses. component7. The children are very mean to the little boy, and _______________ him from all their games. exclude8. You can _______________ on Francis to do the job well; she is an excellent worker. rely9. We didn't _______________ a time exactly, but we'll probably meet at the restaurant around noon. specify10. My _______________ in life is to have fun, and enjoy myself without doing anything to hurt the people around me.11. Psychologists have observed that most of the process of forgetting occurs soon after _______________ exposure. initial12. We didn't have time to finish our discussion of the issue so an additional meeting will be _______________ tomorrow morning. convened13. The various _______________ are manufactured by different suppliers around the world and assembled in our factory in Mexico. components14. My parking pass is only _______________ for another week. valid15. The police say the evidence to this point does not _______________ the possibility that the victim was murdered. exclude16. Rescue forces have as yet been unable to _______________ the plane that crashed into the forest yesterday evening. locate17. He doesn't have a car so he always _______________ on his friends to give him a lift when they go out. relies18. Western _______________ was largely founded on the writings of Plato and Aristotle. philosophy19. The detectives were able to _______________ valuable information about the killer through careful examination of the murder scene. deduce20. The television report stated that many people had died, but didn't _______________ the exact number. specifyExercise 6maximize coordinate sufficient demonstrate framework volume consent physical instance remove1. The Red Cross is trying to _______________ relief efforts aimed at aiding the victims of Sunday's earthquake. coordinate2. To _______________ profits, I suggest we reduce our unit price in order to sell a greater volume of product. maximise3. Please _______________ your shoes when you come into the house. remove4. The curriculum guide provides a _______________ for new teachers to refer to when making lesson plans. framework5. You have to get your parents' _______________ in order to come on the field trip to the lake. consent6. Recent research has _______________ a clear link between smoking parents and ear infections in children. demonstrated7. A further _______________ of computer problems occurred this morning. instance8. The best way to lose weight is to do regular _______________ activity. physical9. Two hours should be _______________ time to finish the work. sufficient10. Fresh apples float because 25 percent of their _______________ is air. volume11. The United Nations Universal Declaration of Human Rights states that marriage shall be entered into only with the free and full _______________ of the intending spouses. consent 12. Recent studies have _______________ that drinking green tea may help to prevent breast cancer. demonstrated13. Some scientists compare the brain to a relay station that merely _______________ incoming signals and outgoing responses. coordinates14. The San Diego freeway in California has the heaviest _______________ of traffic in the world. volume15. Over 100 tons of garbage are _______________ from the Empire State Building each month. removed16. The spaceship that landed on the moon was built to minimize weight and _______________ manoeuvrability. maximize17. A rooftop solar water heater requires about three hours of sunshine per day to provide _______________ hot water for a family of four. sufficient18. A heart attack most often occurs in the morning when mental and _______________ stress are at their peak. physical19. There are many examples of social breakdown. One example is the increase in the _______________ of homeless people in the streets. instance20. The committee met today to discuss the _______________ for the city's bid for the 2040 Olympics. framework。

DS证据理论浙大

5.1 证据理论的发展简况
1、证据理论的名称
证据理论(Evidential Theory) Dempster-Shafer理论 Dempster-Shafer证据理论 DS (或D-S)理论
其它叫法：
Dempster规则 Dempster合成规则 Dempster证据合成规则
2、证据理论的诞生和形成
Outline
本章的主要参考文献证据理论的发展简况经典证据理论关于证据理论的理论模型解释证据理论的实现途径基于DS理论的不确定性推理计算举例
本章的主要参考文献（续1）
[5] Zadeh, L. A. Review of Shafer’s a mathematical theory of evidence. AI Magazine, 1984, 5:81-83. 【对证据理论进行质疑的经典文献之一】
[17] Yaghlane, B. B., et al. Belief function independence: I. The marginal case. International Journal of Approximate Reasoning, 2002, 29(1): 47-70.
[18] Yaghlane, B. B., et al. Belief function independence: II. The conditional case. International Journal of Approximate Reasoning, 2002, 31: 31-75.
[10] Smets, P, and Kennes, R. The transferable belief model. Artificial Intelligence, 1994, 66: 191-234.

c14-test 2-section 4单词整理

C14 Test 2 - Section 4 单词整理1. 介绍本文将针对C14 Test 2 - Section 4中出现的一些重要单词进行整理和解释，以便帮助大家更好地理解和掌握这些单词的用法和意义。

2. analyzeanalyze是一个动词，意思是“分析”，通常用于描述对某个问题或情况进行系统细致的研究和分析。

例如：We need to analyze the data before reaching any conclusions.（在得出任何结论之前，我们需要分析这些数据。

）3. crucialcrucial是一个形容词，意思是“至关重要的”，用于强调某个事情或因素的重要性。

例如：Effectivemunication is crucial in any relationship.4. depictdepict是一个动词，意思是“描述”或“描绘”，通常用于描述艺术作品或文字对事物的详细描绘。

例如：The p本人nting depicts a beautiful countryside scene.（这幅画描绘了美丽的乡村风景。

）5. emphasizeemphasize是一个动词，意思是“强调”或“着重”。

当我们想要强调某个观点或事实时，可以使用这个词。

例如：The speaker emphasized the need for urgent action.6. efficientefficient是一个形容词，意思是“高效的”或“有效率的”，用于描述某个系统或过程能够在少量资源下达到最大产出。

例如：The new system is more efficient than the old one.7. factofacto是拉丁语中“事实”的意思，通常用于表示某个观点或说法是根据实际情况而非猜测得出的。

例如：The decision was made based on the fact that the project was behind schedule.8. simulatesimulate是一个动词，意思是“模拟”或“模仿”，用于描述通过模拟实验或情况来研究某个问题或情况。

基于周期采样的分布式动态事件触发优化算法

第38卷第3期2024年5月山东理工大学学报(自然科学版)Journal of Shandong University of Technology(Natural Science Edition)Vol.38No.3May 2024收稿日期:20230323基金项目:江苏省自然科学基金项目(BK20200824)第一作者:夏伦超,男,20211249098@;通信作者:赵中原,男,zhaozhongyuan@文章编号:1672-6197(2024)03-0058-07基于周期采样的分布式动态事件触发优化算法夏伦超1,韦梦立2,季秋桐2,赵中原1(1.南京信息工程大学自动化学院,江苏南京210044;2.东南大学网络空间安全学院,江苏南京211189)摘要:针对无向图下多智能体系统的优化问题,提出一种基于周期采样机制的分布式零梯度和优化算法,并设计一种新的动态事件触发策略㊂该策略中加入与历史时刻智能体状态相关的动态变量,有效降低了系统通信量;所提出的算法允许采样周期任意大,并考虑了通信延时的影响,利用Lyapunov 稳定性理论推导出算法收敛的充分条件㊂数值仿真进一步验证了所提算法的有效性㊂关键词:分布式优化;多智能体系统;动态事件触发;通信时延中图分类号:TP273文献标志码:ADistributed dynamic event triggerring optimizationalgorithm based on periodic samplingXIA Lunchao 1,WEI Mengli 2,JI Qiutong 2,ZHAO Zhongyuan 1(1.College of Automation,Nanjing University of Information Science and Technology,Nanjing 210044,China;2.School of Cyber Science and Engineering,Southeast University,Nanjing 211189,China)Abstract :A distributed zero-gradient-sum optimization algorithm based on a periodic sampling mechanism is proposed to address the optimization problem of multi-agent systems under undirected graphs.A novel dynamic event-triggering strategy is designed,which incorporates dynamic variables as-sociated with the historical states of the agents to effectively reduce the system communication overhead.Moreover,the algorithm allows for arbitrary sampling periods and takes into consideration the influence oftime delay.Finally,sufficient conditions for the convergence of the algorithm are derived by utilizing Lya-punov stability theory.The effectiveness of the proposed algorithm is further demonstrated through numer-ical simulations.Keywords :distributed optimization;multi-agent systems;dynamic event-triggered;time delay ㊀㊀近些年,多智能体系统的分布式优化问题因其在多机器人系统的合作㊁智能交通系统的智能运输系统和微电网的分布式经济调度等诸多领域的应用得到了广泛的研究[1-3]㊂如今,已经提出各种分布式优化算法㊂文献[4]提出一种结合负反馈和梯度流的算法来解决平衡有向图下的无约束优化问题;文献[5]提出一种基于自适应机制的分布式优化算法来解决局部目标函数非凸的问题;文献[6]设计一种抗干扰的分布式优化算法,能够在具有未知外部扰动的情况下获得最优解㊂然而,上述工作要求智能体与其邻居不断地交流,这在现实中会造成很大的通信负担㊂文献[7]首先提出分布式事件触发控制器来解决多智能体系统一致性问题;事件触发机制的核心是设计一个基于误差的触发条件,只有满足触发条件时智能体间才进行通信㊂文献[8]提出一种基于通信网络边信息的事件触发次梯度优化㊀算法,并给出了算法的指数收敛速度㊂文献[9]提出一种基于事件触发机制的零梯度和算法,保证系统状态收敛到最优解㊂上述事件触发策略是静态事件触发策略,即其触发阈值仅与智能体的状态相关,当智能体的状态逐渐收敛时,很容易满足触发条件并将生成大量不必要的通信㊂因此,需要设计更合理的触发条件㊂文献[10]针对非线性系统的增益调度控制问题,提出一种动态事件触发机制的增益调度控制器;文献[11]提出一种基于动态事件触发条件的零梯度和算法,用于有向网络的优化㊂由于信息传输的复杂性,时间延迟在实际系统中无处不在㊂关于考虑时滞的事件触发优化问题的文献很多㊂文献[12]研究了二阶系统的凸优化问题,提出时间触发算法和事件触发算法两种分布式优化算法,使得所有智能体协同收敛到优化问题的最优解,并有效消除不必要的通信;文献[13]针对具有传输延迟的多智能体系统,提出一种具有采样数据和时滞的事件触发分布式优化算法,并得到系统指数稳定的充分条件㊂受文献[9,14]的启发,本文提出一种基于动态事件触发机制的分布式零梯度和算法,与使用静态事件触发机制的文献[15]相比,本文采用动态事件触发机制可以避免智能体状态接近最优值时频繁触发造成的资源浪费㊂此外,考虑到进行动态事件触发判断需要一定的时间,使用当前状态值是不现实的,因此,本文使用前一时刻状态值来构造动态事件触发条件,更符合逻辑㊂由于本文采用周期采样机制,这进一步降低了智能体间的通信频率,但采样周期过长会影响算法收敛㊂基于文献[14]的启发,本文设计的算法允许采样周期任意大,并且对于有时延的系统,只需要其受采样周期的限制,就可得到保证多智能体系统达到一致性和最优性的充分条件㊂最后,通过对一个通用示例进行仿真,验证所提算法的有效性㊂1㊀预备知识及问题描述1.1㊀图论令R表示实数集,R n表示向量集,R nˑn表示n ˑn实矩阵的集合㊂将包含n个智能体的多智能体系统的通信网络用图G=(V,E)建模,每个智能体都视为一个节点㊂该图由顶点集V={1,2, ,n}和边集E⊆VˑV组成㊂定义A=[a ij]ɪR nˑn为G 的加权邻接矩阵,当a ij>0时,表明节点i和节点j 间存在路径,即(i,j)ɪE;当a ij=0时,表明节点i 和节点j间不存在路径,即(i,j)∉E㊂D=diag{d1, ,d n}表示度矩阵,拉普拉斯矩阵L等于度矩阵减去邻接矩阵,即L=D-A㊂当图G是无向图时,其拉普拉斯矩阵是对称矩阵㊂1.2㊀凸函数设h i:R nңR是在凸集ΩɪR n上的局部凸函数,存在正常数φi使得下列条件成立[16]:h i(b)-h i(a)- h i(a)T(b-a)ȡ㊀㊀㊀㊀φi2 b-a 2,∀a,bɪΩ,(1)h i(b)- h i(a)()T(b-a)ȡ㊀㊀㊀㊀φi b-a 2,∀a,bɪΩ,(2) 2h i(a)ȡφi I n,∀aɪΩ,(3)式中: h i为h i的一阶梯度, 2h i为h i的二阶梯度(也称黑塞矩阵)㊂1.3㊀问题描述考虑包含n个智能体的多智能体系统,假设每个智能体i的成本函数为f i(x),本文的目标是最小化以下的优化问题:x∗=arg minxɪΩðni=1f i(x),(4)式中:x为决策变量,x∗为全局最优值㊂1.4㊀主要引理引理1㊀假设通信拓扑图G是无向且连通的,对于任意XɪR n,有以下关系成立[17]:X T LXȡαβX T L T LX,(5)式中:α是L+L T2最小的正特征值,β是L T L最大的特征值㊂引理2(中值定理)㊀假设局部成本函数是连续可微的,则对于任意实数y和y0,存在y~=y0+ω~(y -y0),使得以下不等式成立:f i(y)=f i(y0)+∂f i∂y(y~)(y-y0),(6)式中ω~是正常数且满足ω~ɪ(0,1)㊂2㊀基于动态事件触发机制的分布式优化算法及主要结果2.1㊀考虑时延的分布式动态事件触发优化算法本文研究具有时延的多智能体系统的优化问题㊂为了降低智能体间的通信频率,提出一种采样周期可任意设计的分布式动态事件触发优化算法,95第3期㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀夏伦超,等:基于周期采样的分布式动态事件触发优化算法其具体实现通信优化的流程图如图1所示㊂首先,将邻居和自身前一触发时刻状态送往控制器(本文提出的算法),得到智能体的状态x i (t )㊂然后,预设一个固定采样周期h ,使得所有智能体在同一时刻进行采样㊂同时,在每个智能体上都配置了事件检测器,只在采样时刻检查是否满足触发条件㊂接着,将前一采样时刻的智能体状态发送至构造的触发器中进行判断,当满足设定的触发条件时,得到触发时刻的智能体状态x^i (t )㊂最后,将得到的本地状态x^i (t )用于更新自身及其邻居的控制操作㊂由于在实际传输中存在时延,因此需要考虑满足0<τ<h 的时延㊂图1㊀算法实现流程图考虑由n 个智能体构成的多智能体系统,其中每个智能体都能独立进行计算和相互通信,每个智能体i 具有如下动态方程:x ㊃i (t )=-1h2f i (x i )()-1u i (t ),(7)式中u i (t )为设计的控制算法,具体为u i (t )=ðnj =1a ij x^j (t -τ)-x ^i (t -τ)()㊂(8)㊀㊀给出设计的动态事件触发条件:θi d i e 2i (lh )-γq i (lh -h )()ɤξi (lh ),(9)q i (t )=ðnj =1a ij x^i (t -τ)-x ^j (t -τ)()2,(10)㊀㊀㊀ξ㊃i (t )=1h[-μi ξi (lh )+㊀㊀㊀㊀㊀δi γq i (lh -h )-d i e 2i (lh )()],(11)式中:d i 是智能体i 的入度;γ是正常数;θi ,μi ,δi 是设计的参数㊂令x i (lh )表示采样时刻智能体的状态,偏差变量e i (lh )=x i (lh )-x^i (lh )㊂注释1㊀在进行动态事件触发条件设计时,可以根据不同的需求为每个智能体设定不同的参数θi ,μi ,δi ,以确保其能够在特定的情境下做出最准确的反应㊂本文为了方便分析,选择为每个智能体设置相同的θi ,μi ,δi ,以便更加清晰地研究其行为表现和响应能力㊂2.2㊀主要结果和分析由于智能体仅在采样时刻进行事件触发条件判断,并在达到触发条件后才通信,因此有x ^i (t -τ)=x^i (lh )㊂定理1㊀假设无向图G 是连通的,对于任意i ɪV 和t >0,当满足条件(12)时,在算法(7)和动态事件触发条件(9)的作用下,系统状态趋于优化解x ∗,即lim t ңx i (t )=x ∗㊂12-β2φm α-τβ2φm αh -γ>0,μi+δi θi <1,μi-1-δi θi >0,ìîíïïïïïïïï(12)式中φm =min{φ1,φ2}㊂证明㊀对于t ɪ[lh +τ,(l +1)h +τ),定义Lyapunov 函数V (t )=V 1(t )+V 2(t ),其中:V 1(t )=ðni =1f i (x ∗)-f i (x i )-f ᶄi (x i )(x ∗-x i )(),V 2(t )=ðni =1ξi (t )㊂令E (t )=e 1(t ), ,e n (t )[]T ,X (t )=x 1(t ), ,x n (t )[]T ,X^(t )=x ^1(t ), ,x ^n (t )[]T ㊂对V 1(t )求导得V ㊃1(t )=1h ðni =1u i (t )x ∗-x i (t )(),(13)由于ðni =1ðnj =1a ij x ^j (t -τ)-x ^i (t -τ)()㊃x ∗=0成立,有V ㊃1(t )=-1hX T (t )LX ^(lh )㊂(14)6山东理工大学学报(自然科学版)2024年㊀由于㊀㊀X (t )=X (lh +τ)-(t -lh -τ)X ㊃(t )=㊀㊀㊀㊀X (lh )+τX ㊃(lh )+t -lh -τhΓ1LX^(lh )=㊀㊀㊀㊀X (lh )-τh Γ2LX^(lh -h )+㊀㊀㊀㊀(t -lh -τ)hΓ1LX^(lh ),(15)式中:Γ1=diag (f i ᶄᶄ(x ~11))-1, ,(f i ᶄᶄ(x ~1n ))-1{},Γ2=diag (f i ᶄᶄ(x ~21))-1, ,(f i ᶄᶄ(x ~2n))-1{},x ~1iɪ(x i (lh +τ),x i (t )),x ~2i ɪ(x i (lh ),x i (lh+τ))㊂将式(15)代入式(14)得㊀V ㊃1(t )=-1h E T (lh )LX ^(lh )-1hX ^T (lh )LX ^(lh )+㊀㊀㊀τh2Γ2X ^T (lh -h )L T LX ^(lh )+㊀㊀㊀(t -lh -τ)h2Γ1X ^T (lh )L T LX ^(lh )㊂(16)根据式(3)得(f i ᶄᶄ(x ~i 1))-1ɤ1φi,i =1, ,n ㊂即Γ1ɤ1φm I n ,Γ2ɤ1φmI n ,φm =min{φ1,φ2}㊂首先对(t -lh -τ)h2Γ1X ^T (lh )L T LX ^(lh )项进行分析,对于t ɪ[lh +τ,(l +1)h +τ),基于引理1和式(3)有(t -lh -τ)h2Γ1X ^T (lh )L T LX ^(lh )ɤβhφm αX ^T (lh )LX ^(lh )ɤβ2hφm αðni =1q i(lh ),(17)式中最后一项根据X^T (t )LX ^(t )=12ðni =1q i(t )求得㊂接着分析τh2Γ2X ^(lh -h )L T LX ^(lh ),根据引理1和杨式不等式有:τh2Γ2X ^T (lh -h )L T LX ^(lh )ɤ㊀㊀㊀㊀τβ2h 2φm αX ^T (lh -h )LX ^(lh -h )+㊀㊀㊀㊀τβ2h 2φm αX ^T (lh )LX ^(lh )ɤ㊀㊀㊀㊀τβ4h 2φm αðni =1q i (lh -h )+ðni =1q i (lh )[]㊂(18)将式(17)和式(18)代入式(16)得㊀V ㊃1(t )ɤβ2φm α+τβ4φm αh -12()1h ðni =1q i(lh )+㊀㊀㊀τβ4φm αh ðni =1q i (lh -h )+1h ðni =1d i e 2i(lh )㊂(19)根据式(11)得V ㊃2(t )=-ðni =1μih ξi(lh )+㊀㊀㊀㊀ðni =1δihγq i (lh -h )-d i e 2i (lh )()㊂(20)结合式(19)和式(20)得V ㊃(t )ɤ-12-β2φm α-τβ4φm αh ()1h ðni =1q i (lh )+㊀㊀㊀㊀τβ4φm αh 2ðn i =1q i (lh -h )+γh ðni =1q i (lh -h )-㊀㊀㊀㊀1h ðni =1(μi -1-δi θi)ξi (lh ),(21)因此根据李雅普诺夫函数的正定性以及Squeeze 定理得㊀V (l +1)h +τ()-V (lh +τ)ɤ㊀㊀㊀-12-β2φm α-τβ4φm αh()ðni =1q i(lh )+㊀㊀㊀τβ4φm αh ðni =1q i (lh -h )+γðni =1q i (lh -h )-㊀㊀㊀ðni =1(μi -1-δiθi)ξi (lh )㊂(22)对式(22)迭代得V (l +1)h +τ()-V (h +τ)ɤ㊀㊀-12-β2φm α-τβ2φm αh-γ()ðl -1k =1ðni =1q i(kh )+㊀㊀τβ4φm αh ðni =1q i (0h )-㊀㊀12-β2φm α-τβ4φm αh()ðni =1q i(lh )-㊀㊀ðlk =1ðni =1μi -1-δiθi()ξi (kh ),(23)进一步可得㊀lim l ңV (l +1)h -V (h )()ɤ㊀㊀㊀τβ4φm αh ðni =1q i(0h )-16第3期㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀夏伦超,等:基于周期采样的分布式动态事件触发优化算法㊀㊀㊀ðni =1(μi -1-δi θi )ðl =1ξi (lh )-㊀㊀㊀12-β2φm α-τβ2φm αh-γ()ð l =1ðni =1q i(lh )㊂(24)由于q i (lh )ȡ0和V (t )ȡ0,由式(24)得lim l ң ðni =1ξi (lh )=0㊂(25)基于ξi 的定义和拉普拉斯矩阵的性质,可以得到每个智能体的最终状态等于相同的常数,即lim t ңx 1(t )= =lim t ңx n (t )=c ㊂(26)㊀㊀由于目标函数的二阶导数具有以下性质:ðni =1d f ᶄi (x i (t ))()d t =㊀㊀㊀㊀-ðn i =1ðnj =1a ij x ^j (t )-x ^i (t )()=㊀㊀㊀㊀-1T LX^(t )=0,(27)式中1=[1, ,1]n ,所以可以得到ðni =1f i ᶄ(x i (t ))=ðni =1f i ᶄ(x ∗i )=0㊂(28)联立式(26)和式(28)得lim t ңx 1(t )= =lim t ңx n (t )=c =x ∗㊂(29)㊀㊀定理1证明完成㊂当不考虑通信时延τ时,可由定理1得到推论1㊂推论1㊀假设通信图G 是无向且连通的,当不考虑时延τ时,对于任意i ɪV 和t >0,若条件(30)成立,智能体状态在算法(7)和触发条件(9)的作用下趋于最优解㊂14-n -1φm -γ>0,μi+δi θi <1,μi-1-δi θi >0㊂ìîíïïïïïïïï(30)㊀㊀证明㊀该推论的证明过程类似定理1,由定理1结果可得14-β2φm α-γ>0㊂(31)令λn =βα,由于λn 是多智能体系统的全局信息,因此每个智能体很难获得,但其上界可以根据以下关系来估计:λn ɤ2d max ɤ2(n -1),(32)式中d max =max{d i },i =1, ,n ㊂因此得到算法在没有时延情况下的充分条件:14-n -1φm -γ>0㊂(33)㊀㊀推论1得证㊂注释2㊀通过定理1得到的稳定性条件,可以得知当采样周期h 取较小值时,由于0<τ<h ,因此二者可以抵消,从而稳定性不受影响;而当采样周期h 取较大值时,τβ2φm αh项可以忽略不计,因此从理论分析可以得出允许采样周期任意大的结论㊂从仿真实验方面来看,当采样周期h 越大,需要的收剑时间越长,但最终结果仍趋于优化解㊂然而,在文献[18]中,采样周期过大会导致稳定性条件难以满足,即算法最终难以收敛,无法达到最优解㊂因此,本文提出的算法允许采样周期任意大,这一创新点具有重要意义㊂3㊀仿真本文对一个具有4个智能体的多智能体网络进行数值模拟,智能体间的通信拓扑如图2所示㊂采用4个智能体的仿真网络仅是为了初步验证所提算法的有效性㊂值得注意的是,当多智能体的数量增加时,算法的时间复杂度和空间复杂度会增加,但并不会影响其有效性㊂因此,该算法在更大规模的多智能体网络中同样适用㊂成本函数通常选择凸函数㊂例如,在分布式传感器网络中,成本函数为z i -x 2+εi x 2,其中x 表示要估计的未知参数,εi 表示观测噪声,z i 表示在(0,1)中均匀分布的随机数;在微电网中,成本函数为a i x 2+b i x +c i ,其中a i ,b i ,c i 是发电机成本参数㊂这两种情境下的成本函数形式不同,但本质上都是凸函数㊂本文采用论文[19]中的通用成本函数(式(34)),用于证明本文算法在凸函数上的可行性㊂此外,通信拓扑图结构并不会影响成本函数的设计,因此,本文的成本函数在分布式网络凸优化问题中具有通用性㊂g i (x )=(x -i )4+4i (x -i )2,i =1,2,3,4㊂(34)很明显,当x i 分别等于i 时,得到最小局部成本函数,但是这不是全局最优解x ∗㊂因此,需要使用所提算法来找到x ∗㊂首先设置重要参数,令φm =16,γ=0.1,θi =1,ξi (0)=5,μi =0.2,δi =0.2,26山东理工大学学报(自然科学版)2024年㊀图2㊀通信拓扑图x i (0)=i ,i =1,2,3,4㊂图3为本文算法(7)解决优化问题(4)时各智能体的状态,其中设置采样周期h =3,时延τ=0.02㊂智能体在图3中渐进地达成一致,一致值为全局最优点x ∗=2.935㊂当不考虑采样周期影响时,即在采样周期h =3,时延τ=0.02的条件下,采用文献[18]中的算法(10)时,各智能体的状态如图4所示㊂显然,在避免采样周期的影响后,本文算法具有更快的收敛速度㊂与文献[18]相比,由于只有当智能体i 及其邻居的事件触发判断完成,才能得到q i (lh )的值,因此本文采用前一时刻的状态值构造动态事件触发条件更符合逻辑㊂图3㊀h =3,τ=0.02时算法(7)的智能体状态图4㊀h =3,τ=0.02时算法(10)的智能体状态为了进一步分析采样周期的影响,在时延τ不变的情况下,选择不同的采样周期h ,其结果显示在图5中㊂对比图3可以看出,选择较大的采样周期则收敛速度减慢㊂事实上,这在算法(7)中是很正常的,因为较大的h 会削弱反馈增益并减少固定有限时间间隔中的控制更新次数,具体显示在图6和图7中㊂显然,当选择较大的采样周期时,智能体的通信频率显著下降,同时也会导致收敛速度减慢㊂因此,虽然采样周期允许任意大,但在收敛速度和通信频率之间需要做出权衡,以选择最优的采样周期㊂图5㊀h =1,τ=0.02时智能体的状态图6㊀h =3,τ=0.02时的事件触发时刻图7㊀h =1,τ=0.02时的事件触发时刻最后,固定采样周期h 的值,比较τ=0.02和τ=2时智能体的状态,结果如图8所示㊂显然,时延会使智能体找到全局最优点所需的时间更长,但由于其受采样周期的限制,最终仍可以对于任意有限延迟达成一致㊂图8㊀h =3,τ=2时智能体的状态36第3期㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀夏伦超,等:基于周期采样的分布式动态事件触发优化算法4　结束语本文研究了无向图下的多智能体系统的优化问题,提出了一种基于动态事件触发机制的零梯度和算法㊂该机制中加入了与前一时刻智能体状态相关的动态变量,避免智能体状态接近最优值时频繁触发产生的通信负担㊂同时,在算法和触发条件设计中考虑了采样周期的影响,在所设计的算法下,允许采样周期任意大㊂对于有时延的系统,在最大允许传输延迟小于采样周期的情况下,给出了保证多智能体系统达到一致性和最优性的充分条件㊂今后拟将本算法向有向图和切换拓扑图方向推广㊂参考文献:[1]杨洪军,王振友.基于分布式算法和查找表的FIR滤波器的优化设计[J].山东理工大学学报(自然科学版),2009,23(5):104-106,110.[2]CHEN W,LIU L,LIU G P.Privacy-preserving distributed economic dispatch of microgrids:A dynamic quantization-based consensus scheme with homomorphic encryption[J].IEEE Transactions on Smart Grid,2022,14(1):701-713.[3]张丽馨,刘伟.基于改进PSO算法的含分布式电源的配电网优化[J].山东理工大学学报(自然科学版),2017,31(6):53-57.[4]KIA S S,CORTES J,MARTINEZ S.Distributed convex optimization via continuous-time coordination algorithms with discrete-time communication[J].Automatica,2015,55:254-264.[5]LI Z H,DING Z T,SUN J Y,et al.Distributed adaptive convex optimization on directed graphs via continuous-time algorithms[J]. IEEE Transactions on Automatic Control,2018,63(5):1434 -1441.[6]段书晴,陈森,赵志良.一阶多智能体受扰系统的自抗扰分布式优化算法[J].控制与决策,2022,37(6):1559-1566. [7]DIMAROGONAS D V,FRAZZOLI E,JOHANSSON K H.Distributed event-triggered control for multi-agent systems[J].IEEE Transactions on Automatic Control,2012,57(5):1291-1297.[8]KAJIYAMA Y C,HAYASHI N K,TAKAI S.Distributed subgradi-ent method with edge-based event-triggered communication[J]. IEEE Transactions on Automatic Control,2018,63(7):2248 -2255.[9]LIU J Y,CHEN W S,DAI H.Event-triggered zero-gradient-sum distributed convex optimisation over networks with time-varying topol-ogies[J].International Journal of Control,2019,92(12):2829 -2841.[10]COUTINHO P H S,PALHARES R M.Codesign of dynamic event-triggered gain-scheduling control for a class of nonlinear systems [J].IEEE Transactions on Automatic Control,2021,67(8): 4186-4193.[11]CHEN W S,REN W.Event-triggered zero-gradient-sum distributed consensus optimization over directed networks[J].Automatica, 2016,65:90-97.[12]TRAN N T,WANG Y W,LIU X K,et al.Distributed optimization problem for second-order multi-agent systems with event-triggered and time-triggered communication[J].Journal of the Franklin Insti-tute,2019,356(17):10196-10215.[13]YU G,SHEN Y.Event-triggered distributed optimisation for multi-agent systems with transmission delay[J].IET Control Theory& Applications,2019,13(14):2188-2196.[14]LIU K E,JI Z J,ZHANG X F.Periodic event-triggered consensus of multi-agent systems under directed topology[J].Neurocomputing, 2020,385:33-41.[15]崔丹丹,刘开恩,纪志坚,等.周期事件触发的多智能体分布式凸优化[J].控制工程,2022,29(11):2027-2033. [16]LU J,TANG C Y.Zero-gradient-sum algorithms for distributed con-vex optimization:The continuous-time case[J].IEEE Transactions on Automatic Control,2012,57(9):2348-2354. [17]LIU K E,JI Z J.Consensus of multi-agent systems with time delay based on periodic sample and event hybrid control[J].Neurocom-puting,2016,270:11-17.[18]ZHAO Z Y.Sample-baseddynamic event-triggered algorithm for op-timization problem of multi-agent systems[J].International Journal of Control,Automation and Systems,2022,20(8):2492-2502.[19]LIU J Y,CHEN W S.Distributed convex optimisation with event-triggered communication in networked systems[J].International Journal of Systems Science,2016,47(16):3876-3887.(编辑:杜清玲)46山东理工大学学报(自然科学版)2024年㊀。

创新英语试题及答案

创新英语试题及答案一、选择题（每题2分，共20分）1. Which of the following is NOT a characteristic of innovation?A. CreativityB. Risk-takingC. TraditionD. Flexibility答案：C2. Innovation often involves:A. Following established rulesB. Breaking existing paradigmsC. Repetition of past successesD. Resistance to change答案：B3. The primary goal of innovation in business is to:A. Cut costsB. Increase salesC. Simplify processesD. All of the above答案：D4. Which of the following is NOT a benefit of innovation?A. Improved efficiencyB. Enhanced competitivenessC. Reduced job securityD. New opportunities答案：C5. Innovation can be driven by:A. Market demandB. Technological advancementsC. Regulatory changesD. All of the above答案：D6. A common challenge faced by innovators is:A. Lack of resourcesB. Lack of ideasC. Overabundance of ideasD. Lack of motivation答案：A7. Which of the following is a key element of successful innovation?A. PersistenceB. LuckC. IgnoranceD. Disorganization答案：A8. The process of innovation often requires:A. CollaborationB. IsolationC. CompetitionD. Conformity答案：A9. In the context of innovation, "disruption" refers to:A. The act of causing chaosB. The act of breaking thingsC. The act of introducing new ideas that change the marketD. The act of maintaining the status quo答案：C10. One way to foster innovation is by:A. Discouraging experimentationB. Encouraging experimentationC. Punishing failureD. Rewarding only success答案：B二、填空题（每题1分，共10分）1. The concept of "blue ocean strategy" is often associated with __________ in business.答案：innovation2. A __________ is a person who introduces new methods, ideas,or products.答案：innovator3. The term "disruptive innovation" was popularized by the business strategist __________.答案：Clayton M. Christensen4. Innovation can lead to the creation of new __________ in the market.答案：industries5. The process of innovation often involves __________ and testing of new ideas.答案：research6. A __________ is a system that encourages and rewards creative thinking.答案：culture of innovation7. In the context of innovation, "sustainable" refers to practices that can be __________ over time.答案：maintained8. The ability to adapt to new technologies and methods is a key aspect of __________.答案：innovative capacity9. An __________ is a new product, service, or process that is introduced to the market.答案：innovation10. The process of innovation often involves a degree of__________.答案：uncertainty三、简答题（每题5分，共20分）1. Define the term "innovation" and give an example.答案：Innovation refers to the process of translating an idea or invention into a good or service that creates value or for which customers will pay. An example of innovation is the development of smartphones, which have revolutionized the way we communicate and access information.2. Explain the difference between incremental and disruptive innovation.答案：Incremental innovation involves making small, gradual improvements to existing products or services. Disruptive innovation, on the other hand, involves creating new markets and value networks and often disrupts existing markets by introducing new technologies or business models.3. What are the key factors that drive innovation?答案：Key factors that drive innovation include market demand, technological advancements, competition, regulatory changes, and a culture that encourages creativity and risk-taking.4. How can organizations foster a culture of innovation?答案：Organizations can foster a culture of innovation by encouraging creative thinking, providing resources for experimentation, recognizing and rewarding innovative efforts, and being open to change and new ideas.四、论述题（共50分）1. Discuss the importance of innovation in today's rapidly changing business environment. (25分)答案：In today's rapidly changing business environment, innovation is crucial for organizations to stay competitive. It allows them to adapt to new technologies, meet evolving customer needs, and create new markets. Innovation can lead to increased efficiency, improved products and services, and ultimately, greater profitability. It also helps organizations to anticipate and respond to market changes, ensuring their long-term survival and growth.2. Describe a successful innovation process and explain why it was successful. (25分)答案：A successful innovation process typically involves several key stages:。

面向疾病的空间聚集性与影响因素分析方法

2097-3012(2024)01-0065-09 Journal of Spatio-temporal Information 时空信息学报收稿日期: 2022-06-30；修订日期: 2023-12-15 基金项目: 国家自然科学基金（42201490）作者简介: 胡涛，研究方向为时空大数据分析与可视化。

E-mail:*****************通信作者: 王丽娜，研究方向为地理信息可视化、疾病制图。

E-mail:***************面向疾病的空间聚集性与影响因素分析方法胡涛1，王丽娜2，李响1，张正斌3，俞鑫楷11. 信息工程大学地理空间信息学院，郑州450052；2. 郑州轻工业大学计算机科学与技术学院，郑州 450001；3. 武汉市结核病防治所结核病控制办公室，武汉430030摘要：疾病的发生与自然环境、社会环境和人群特点密切相关，其发生与流行通常具有一定的空间分布特征。

目前在疾病空间聚集特征与影响因素的已有研究中缺少两者关联关系的探讨，以及空间尺度多集中于省、市和县域，因此，本研究提出一种面向疾病空间聚集性与影响因素分析的方法。

以武汉市的历史肺结核数据为例，进行基于乡镇尺度的肺结核发病率数据及影响因素数据的处理与整合，基于空间自相关方法分析2011年、2013年和2015年肺结核空间聚集情况；并运用地理探测器探测肺结核发病率空间分布的影响因素及交互作用，探究肺结核空间聚集的成因。

结果表明：肺结核热点聚集乡镇主要分布在新洲区、江夏区和蔡甸区，冷点聚集乡镇主要分布在洪山区；植被指数、人口密度、人均GDP 及五类兴趣点密度（医疗保健类、生活服务类、餐饮类、住宅类和农林牧渔类）为肺结核发病率空间分布的主要影响因素，其交互作用对肺结核发病率影响显著增强。

研究成果可为武汉市肺结核防治提供科学参考。

关键词：肺结核；空间聚集性；空间自相关；地理探测器；兴趣点引用格式：胡涛, 王丽娜, 李响, 张正斌, 俞鑫楷. 2024. 面向疾病的空间聚集性与影响因素分析方法. 时空信息学报, 31(1): 65-73Hu T, Wang L N, Li X, Zhang Z B, Yu X K. 2024. Analysis method for disease-oriented spatial clustering and influencing factors. Journal of Spatio-temporal Information, 31(1): 65-73, doi: 10.20117/j.jsti.2024010091 引言计算机科学、地理信息系统和空间分析技术快速发展，为挖掘多维、海量的疾病数据提供了坚实的技术基础，并广泛应用于流行病的预警、聚类分析、疾病制图等方面（施迅和王法辉，2016；李杰等，2020；陈曦和闫广华，2021）。

公共管理经典书目

公共管理经典书目（一）基础理论经典原著1、威尔逊：《行政学之研究》，《国外政治学》1987年第6期、1988年第1期。

2、古德诺：《政治与行政》，华夏出版社1987年版。

3、泰罗：《科学管理原理》，中国社会科学出版社1990年版。

4、法约尔：《工业管理与一般管理》，中国社会科学出版社1998年版。

5、马克斯·韦伯：《经济与社会》，商务印书馆1997年版。

6、怀特：《行政学概论》，上海商务印书馆1947年版。

7、西蒙：《管理行为》，北京经济学院出版社1988年版。

8、西蒙：《管理决策新科学》，中国社会科学出版社1982年版。

9、沃尔多：《行政国家：美国公共行政的政治理论研究》，纽约：罗纳德出版社1948年版。

10、林德布洛姆：《决策过程》，上海译文出版社1988年版。

11、德罗尔：《逆境中的政策制定》，上海远东出版社1996年版。

12、雷格斯：《行政生态学》，台湾商务印书馆1985年版。

13、弗雷德里克森：《新公共行政学》，美国亚拉巴马大学出版社1980版。

14、奥斯特罗姆：《美国公共行政的思想危机》上海三联书店1999年版。

15、尼斯坎南：《官僚制与公共经济学》，中国青年出版社2004年版。

16、詹姆斯·Q·威尔逊：《官僚机构：政府机构的作为及其原因》，三联书店2006年版。

17、奥斯特罗姆：《公共服务的制度建构》上海三联书店2000年版。

18、布坎南、塔洛克：《同意的计算：立宪民主的逻辑基础》，中国社会科学出版社2000年版。

19、缪勒：《公共选择理论》，中国社会科学出版社1999年版。

20、罗森布鲁姆：《公共行政学：管理、政治和法律的途径》，中国人民大学出版社2002年版。

21、R·J·斯蒂尔曼：《公共行政学：概念与案例》，中国人民大学出版社2004年版。

22、罗伯特•登哈特：《公共组织理论》，中国人民大学出版社2003年版。

23、沙夫里茨、海德：《公共行政学经典》，中国人民大学出版社2004年英文版。

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the 1990s, an explosion of literature concerning material flows in industrial society and their relationship to environmental issues occurred. Fischer-Kowalski(1998) provides a review of arricles and books during this time.Terms such as “industrial metabolism”, “dematerialization”, and “material intensity of use”pervades the literature and reflected a growing view: the view that material flows are major, fundamental part of environmental issues in an industrialized economy and that understanding these flows is the first step to improving our relationship with the environment.Input-output analysis is one approach included in the increased activity revolving around environmental issues in industry. It is a modeling approach originally applied to model the monetary transactions between industrial sectors of an economy . In this article , however, “the economy is viewed as a set of transformations of physical materials from the raw state through successive stages of extracting and processing to goods and services,and finally to return flows consisting of wastes (which may or may not be recyclable)”(Ayres,1978, 5).Like other MFA approaches, the Input-output approach introduced here is based on the conservation of mass. Unlike other approaches, however, Input-output mathematics facilitates the tracing of both direct and indirect flow paths through material flow systems and the corresponding generation of material flow metrics.No other MFA approach mathematically handles both direct and indirect flow paths.Relevant literature regarding Input-output techniques and their application to material and energy flows in industry is examined in the following section.Input-output mathematics:economic beginningThe origins of Input-output techniques are distinctly economic,with the earliest conceptions of Input-output approaches dating to quesnay’s tableau economique in 1758.The most significant step in bringing input-output techniques into their current form,however,came nearly two centuries later when Leontief introduced Input-output economics.As originally put forth by Leontief, Input-output economics is used to determine the direct and indirect input requirements(i.e,the production of each industrial sector,in dollars)for a complex system of industries (in his case, U.S.industries) needed to produce a given output from a particular industrial sector (i.e,a demand vector,in dollars).The work of Leontief serves as the basis from which all later research in Input-output approaches is founded.Leontief’s original Input-output formulation traces dollar hows from a given amount of output(i.e, demand) backward to the inputs (in dollars) required to support that output(1936).an economy,in Leontief’s approach, is divided into industrial sectors(e.g.,motor freight transportation,lubricants and grease,petroleum refining),and dollar flows between the sectors are modeled. Taxonomies used to divide the economy into sectors include the Standard Industrial Classification(SIC) and, as of 1997, the North American Industry Classification System century focused on applying Input-output techniques to materials,energy ,or environmental impact. Many of these efforts are based on the traditional industrial sector approach (Baumol and Wolff 1994;Forsund 1985),the differences with Leontief’s original Input-output analysis being that materials, energy,or environmental impact are integrated into the economic,sector-based analysis.Input-0utput Mathematics: Industrial ExtensionsSeveral notable applications of traditional, sector-based Input-output approaches integrated with material,energy, or environmental impact are introduced in this section. All of theseapplications are categorized in figure1. These main subsets of Input-output approaches are represented in figure 1.Approaches that include material and/or energy flows(region A)Approaches that are focused on environmental issues facing industry (region B)Approaches that are neither economic nor industrial-sector based (region C)1990年代,关于物质流在工业社会以及其与环境问题发生的关系的爆炸性文献。

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Clavis: a temporal reasoning systemfor classification of audiovisual sequencesJean Carrive & François Pachet & Rémi RonfardInstitut National de l’Audiovisuel (I.N.A) SONY CSL–Paris4, av. de l’Europe 6, rue Amyot94 366 Bry sur Marne Cedex, France 75005 Paris, Francerronfard}@ina.fr pachet@csl.sony.fr{jcarrive,AbstractIn the context of video indexing, we present the Clavis system in which typical video sequences of television programs are represented by templates. Templates are terminological constraint networks in which video segments coming from automatic analysis tools are represented in a description logic formalism. Templates allow to express complex classes of video sequences with temporal constraints associated to a regular expression operator. Recognizing occurrences of a template in a video program is a plan recognition problem for which efficient methods have been implemented in a constraint satisfaction problem framework. The paper describes the system and illustrates its use with several experiments that were done in the context of the DiVAN european project.IntroductionAn important step towards content-based indexing television programs is the segmentation of the video into independent meaningful units, intermediate between the shot and the complete program. This is an inherently ill-posed problem in general, since even experts fail to agree on a common vocabulary of those units, and how to compare different segmentations. The problem becomes more tractable in more constrained situations, such as a collection of videos built on a common pattern or model. In that case, we can view segmentation as a plan recognition problem, where the plans to be recognized are characteristic of a collection of videos – such as a particular broadcast news or variety show. In this communication, we introduce a representation language and a computational framework for building such abstract models of television program collections, and recognizing the models from observations.In (Ronfard, 1997) it was first proposed to use a description logic to describe and index video shots with a rich set of film concepts. (Carrive et al., 1998) further elaborated on this idea, and extended the proposal to a general taxonomy of film events, useful in the description and the analysis of video documents in the large. In this paper, we present Clavis (Classification of Video Sequences), a system which classifies typical video sequences found in collections of television programs, using temporal compositions of film events. The classes of sequences are represented as templates which are terminological constraints networks. Recognizing occurrences of templates within the video is presented as a plan recognition problem and the solution proposed is an extension of the T-Rex system originally proposed by (Weida, 1995), which combines symbolic temporal relations with a regular expression operator.The paper is structured as follows. In section 0, we describe how classes of video segments coming from automatic analysis tools are represented in a description logic formalism, and used as building blocks of the Clavis system. In Section 3, we further explain how templates are defined as terminological constraints network and how the recognition process is designed. Finally in Section 4,we present some experiments that were done in the context of the DiVAN (Distributed AudiovisualArchives Network) project1.Templates: descriptions of video sequencesA lot of periodic television programs, such as newscasts, variety shows or magazines, follow apredefined scenario which presents very little variation from one edition to another. These programsare part of what is called a collection. We propose to describe typical sequences of such programs using templates and we use a plan recognition algorithm based on Weida’s work on terminologicalconstraints network (Weida, 1995).A plan recognition problemWe claim that recognising the occurrences of a template in a television program is similar torecognising which plan some active agent is following (Kautz, 1991) or recognising which predefined scenario best describes the evolution of a dynamic system (Ramaux et al., 1996), and we present thisproblem as a plan recognition problem. In (Fontaine, 1996), the author distinguishes four steps in a plan recognition process: opportunity, filtering, activation and discrimination. We will concentrate inthis paper on the last step, which can be formulated in our case as the problem of finding in a video program made of automatically labelled segments the occurrences of a typical sequence representedby a template2. This recognition process often results in attributing a modality to the plan beingprocessed, depending on whether the observations satisfy, don’t satisfy or are compatible with the plan (Weida, 1995). (Ramaux and Fontaine, 1996) present a method that computes a proximity measurebetween the plan and the observations. We will focus in this paper on determining whether a set of observations satisfies or don’t satisfies a template. It has turned out that determining whether theobservations are compatible with a template is difficult and we temporarily put this task to one’s side. Following (Weida, 1995), we define a template as a terminological constraint network. The vertices ofthe network are associated with concepts which describe classes of video segments coming from audio or video analysis tools. The edges of the network are temporal constraints which have to be respectedby the observations, i.e. the video segments coming from the analysis tools. In addition to Weida’sformalism, we define an iteration operator “*” which expresses a contiguous sequence of video segments. For instance, a simple template may describe a report as a sequence of consecutive shotswith a logo appearing during the first shot of the sequence. This template is defined by the following expression:Report Array nodes: s1 [Shot]s2 [Shot*]s3 [Logo]constraints : s1 {meets} s2s3 {starts∨during∨finishes} s1s1 {starts} thiss3 {finishes} thisClassification of basic film eventsEverything that appears on the screen, or is heard in the soundtrack constitutes an event. In this paper, we will consider that the temporal part of an event is only a time interval – for example a start point and a duration – identifying the temporal occurrence of the event within the video. Much like in grammars, we assume that a video is composed of several terminals, which we call segments. These1 DiVAN is the Esprit project N° 24956.2 We choose the term “template” because scenario or plan (“plan” means “shot” in French) are ambiguous in thetelevision domain.events are terminal because they are not themselves composed of other segments. An event can be a particular shot, which is what is filmed in one shot of the camera, a segment of music, a gradual transition between two shots as a dissolve, etc.When applied in the context of DiVAN, the complete indexing process consists of the following steps: 1) initial segmentation of the audio and video track, producing at least two separate segmentation layers (usually more); 2) feature extraction and classification of segments, based on learned statistical models; 3) symbolic classification, using DL descriptions; and 4) recognition of composite events. In this paper, we assume the results from 1) and 2) provide a set of terminal events and focus on step 3) and 4).Description Logics Description logics (Nebel, 1990) form a family of knowledge representation languages which derive from works on semantic networks and frame languages. In a description logic, concepts represent sets of individuals, and roles represent binary relations between individuals. Concepts can be seen as unary logical predicates, as roles are similar to binary logical predicates. Concepts can be described by syntactic operators as intersection (AND), union (OR), restrictions on the domain of a role or on the cardinality of a role. Concepts (and sometimes roles) are organized into a taxonomy according to a generality link – a subsumption link. Computing the subsumption relation between two concepts is one of the principal task of a description logic system. Instantiation is one other important operation, which compute the set of concept an individual belongs to. Primitive concepts are defined with necessary – and not sufficient – conditions, as defined concepts are defined with necessary and sufficient conditions.Taxonomy of film events Using the CLASSIC system (Borgida, 1989), we define classes of events as concepts, focusing of classes of events which can be automatically recognized by audio and/or video analysis tools, such as those which are integrated in the DiVAN prototype: segmentation into shots, face regions and text regions detection, music/speech discrimination, jingle detection in the audio track, for example.Figure 1 shows five concepts corresponding to cases where a face region can be detected clearly. These concepts are derived from terms of a cinematographic vocabulary, called “shot values”, and range from close-up (CU), where the face occupies approximately half of the screen, to the long shot (LS), where the human figure is seen entirely, and the face occupies around ten percent of the screen. Intermediate shot values are the medium shot (MS), the medium-close-up (MCU) and the medium-long-shot (MLS) (Thompson, 1998). Shot values are usually defined in relative and imprecise terms, based on the distance of the subject to the camera. We use the fact that the apparent size of faces on screen vary inversely with their distance to the camera to provide a computable definition of shot values. The ratio of the width of the face to the width of the frame is used to classify a shot among the five concepts. For example, the CLASSIC definition of a MCU shot is the following:'MCU-Face(cl-define-concept`(andface(all face-ratio (and (min ,(/ 1 6)) (max ,(/ 1 2))))))Figure 1: shot valuesThe algorithm used in DiVAN to segment a video into shots also detects two different classes of progressive transitions between shots, namely dissolves and wipes. In a dissolve, the existing image isprogressively replaced by superimposing a new image. In a wipe, a geometric pattern – often a simple line – erases the existing image and reveals the new one. This editing effects are illustrated by Figure 2.Figure 2: progressive transitions between shotsIn may happen in some collections of documents that low-level features can directly provide high-level information. For example, in the five editions of the “France 3” evening newscast “Soir 3” from the DiVAN corpus, when some text is displayed at the bottom left of the screen during a medium close-up shot of a character, the text always refers to the character on-screen, mentioning its name and sometimes its function or role (see Figure 3). Thus, a “named person shot” can be defined by the very simple CLASSIC expression:(cl-define-concept ‘NamedPersonShot‘(andMCUBottomLeftTextShot)))Figure 3: example of a NamedPersonShotWhen a shot is classified both as a MCUShot and as a BottomLeftTextShot, it is automatically classified as a NamedPersonShot. The definition of this concept is specific to the “Soir 3” newscast. Specific concepts are defined for each collection, starting from generally defined concepts as MCU. In other words, a general taxonomy of concepts is specialized for each collection of programs.Constraint networksA template is a temporal constraint network whose vertices are associated with concepts defined in a description logic formalism, or with other templates. A vertex associated with a concept is called an “elementary” vertex and a vertex associated with a template is told a “composed” vertex. An iteration operator “*” is defined which can be applied on the vertices of the network which are associated with concepts or with certain types on templates. This types of templates will be discussed later. The “*” operator can be compared to the “+” operator in regular expressions, as it indicates a contiguous sequence of at least one element. Non iterated vertices are told “simple” vertices. This iteration operator indicates a sequence of contiguous events. This leads to four different types of vertices:• simple elementary vertices (v C)• simple composed vertices (v T)• iterated elementary vertices (v C*)• iterated composed vertices (v T*)The edges of the network are temporal constraints. In the current implementation of the system, these temporal constraints are temporal relations in the full interval algebra. A template is recognized – or satisfied – if and only if :• each simple elementary vertex v C is matched with an observation which is an instance C;• each simple composed vertex v T is matched with a subset of the observations which satisfies T;• each iterated elementary vertex v C* is matched with a subset of the observations forming a contiguous sequence of instances of C;• each iterated composed vertex v T* is matched with a subset of the observations forming a contiguous sequence of satisfied templates T;• the matching respect the temporal constraints defined in the template.When a set of observations satisfies a template T, it is said to be an instance of T. Without iterated vertices, the problem of template recognition comes down to find a matching between the constraint network and the observation network. This network matching problem has been proved to be NP-hard (Weida, 1995). Recognizing templates with iterated vertices lead to matching vertices of the template with sub-networks of the observation network. In order to avoid a combinatorial explosion, we designed methods which are very efficient for the type of cases we have to deal with. An overview of these methods is presented in section 0.Temporal constraintsSeveral representations of time may underlie a temporal constraint network. The two main categories are the time point algebra (Vilain et al., 1989) and the time interval algebra (Allen, 1983). Complete constraint propagation in the latter representation is NP-hard and tractable subclasses of this algebra have been proposed (Nebel et al., 1994; Drakengren et al., 1997). Following (Weida, 1995) we have chosen the full interval algebra with a 3-path consistency constraint propagation algorithm which is potentially non complete. The reason why we choose this formalism is that when we started this work we didn’t have a precise idea on what would be the most appropriate representation of time. We thus adopted this very general and expressive formalism. In a second step, we should work on determining what are the temporal constraints we really need. For example, it appeared on the one hand that numerical constraints such as “a segment of music which starts less than 30 seconds before a shot”, as in (Aigrain, 1997), would enhance the powerfulness of our system. On the other hand, the full expressiveness of Allen’s algebra didn’t appear yet to be necessary.The temporal extension of an instance t of a template T can be specified in the template definition by setting temporal constraints between t – or more precisely what will be t when T will be recognized – and its components. The instance of a template is designed by “this” in the template definition. For example, the template illustrated by Figure 4 defines a “musical shot” as a shot which appears during a musical segment. The temporal extension of a musical shot is naturally set as being equal to the observed shot. Note that any disjunction of Allen’s relations may be set between the instance of a template and its components.MusicalShotnodes: s1[Shot ]s2[Musicconstraints: s2 during s1s1 equals thisFigure 4: temporal extension of an instance of templateIterated sequencesAn iterated vertex v C* or v T* in a template represent a contiguous sequence of observations which are instances of C or instances of T . An iterated sequence contains at least one element, and the elements of an iterated sequence are contiguous, which means that two successive elements must be related by the Allen’s meets relation. The temporal extension of an iterated sequence is defined as the temporal union of the temporal extensions of its elements. This implies that the temporal extensions of those elements are known, which lead to limit the types of templates which can be associated to an iterated vertex (see section 0). These types of templates are what we call “bounded” templates, i.e. templates whose temporal extension of instances may be computed. Roughly, a template is bounded if some of its vertices are in such a temporal relation with “this” that the temporal extension of its instances may be computed from the temporal extension of its components. This vertices have to be associated with event concepts or with other bounded templates. The temporal relations that allow to compute the starting point are starts , is-started , meets , equals , and the temporal relations that allow to compute the ending point are finishes , is-finished , is-met , equals.The Figure 5 illustrates an iterated sequence of the template MusicalShot illustrated by Figure 4. Note is this example that the same segment of music was used to recognize each of the shots as instances of the MusicalShot template.Figure 5: example of an iterated sequence Other constraintsOnce the general architecture of a template is designed as a temporal constraint network whose vertices are associated to concepts in a taxonomy of audiovisual events or with other templates, and whose vertices may be iterated in some cases, it is possible to define other constraints on its vertices. For example, we define a “no … between” constraint telling that for a template to be recognized, there should be no instance of some concept C or some template T between the observations matched with two of the vertices of the template. For example, the template illustrated by Figure 6 defines a report as the sequence of shots that is shown between two consecutive “jingle” shots, a jingle shot being a shot during which some instance of Jingle is heard.Reportnodes: s1[Shotconstraints s1meetss2s2meets s3s4durings1s5during s3s2equals thisnoJinglebetween s4 s5Figure 6: example of template with a “no … between” constraintOther constraints could be easily defined, which would be taken into account by the constraint solver during the recognition process. It might be for cardinality constraints on the number of elements of an iterated sequence, or even numerical constraints on the temporal dimension of vert ices, as “two instances of Jingle separated by at least 30 seconds”. Note however that these constraints would not be taken into account during the construction of the temporal constraint network, and thus that inconsistencies would not be detected. In this case, the recognition process would scan the whole search space before answering that there are no solutions.CSP techniques for template recognitionThe problem of recognizing instances of a template T among the observations is expressed as a constraint satisfaction problem (CSP). Roughly, each vertex of T gives a variable of the CSP. Each variable takes its values from its domain, a finite set of possible values. The solutions of the problem are expressed as a set of constraints which are boolean functions whose arguments are variables.In this section, we give an overview of the implementation of the Clavis system, focusing on the recognition of iterated sequences. The implementation deeply relies on BackJava (Roy et al., 1999), a (CSP) framework which allows to implement specific classes or variables, constraints and even domains or heuristics as subclasses of general purpose predefined classes. Thus, general mechanisms as arc-consistency can be used, as specialized filtering methods can be defined. In the system presented here, we use general unary constraints for checking that a simple elementary vertices are matched with observations that are instances of the concept associated with the vertex, general binary constraints for temporal constraints between simple vertices and specialized filtering method for temporal constraints which implies iterated vertices. These methods are sketched below. Finally, we let the default resolution mechanism of BackJava realize the recognition process, i.e. we let it choose when it should instantiate a new variable, which variable to choose, when it should backtrack, etc. The time responses we get during the experimentations we did – a few seconds for templates with iterated composed vertices with about 200 observed events – were quite encouraging and we didn’t try to optimize the resolution phase.The most complicated part of the implementation concerns iterated vertices of templates. We describe what is done with iterated elementary vertices. Iterated composed vertices associated with a template T are managed in a similar way after all instances of T have been recognized. Each iterated elementary vertex v C* gives an “iterated variable” of the CSP. The first problem is to represent the domain of the variable, i.e. the set of iterated sequences of instances of C. The number of such sequences can be veryimportant. For example, for an observation network made of N consecutive shots, there are N(N+1)2distinct iterated sequences of shots. In this case, illustrated by Figure 7, all sequences of shots may be represented as sub-sequences of the biggest sequence of shots, which is called a “maximal” sequence.A maximal sequence of instances of C is an iterated sequence of instances of C where no observation is both an instance of C and is in the meets relation (respectively the is-met) relation with its first (respectively its last) element. Each sub-sequence is uniquely determined by its size and the index ofits first element in the maximal sequence. An indexing function is used, which associates a uniqueinteger between 0 and N(N+1)2 -1 to all sub-sequences of a maximal sequence of size N according totheir size and the index of their first element in the maximal sequence. The domain of an iterated variable is thus represented as a list of integers which is internally implemented as a list of intervals. This kind of integer variables are already implemented in BackJava which takes in charge basic operations on intervals, like union or intersection.Figure 7: representation of sub-sequencesIn order to compute the domain of an iterated variable representing an iterated vertex v C*, one’s must first compute the set of all maximal sequences of instances of C. This computation could be very expensive in the general case, but is quite acceptable for the kind of cases we have to process. Temporal constraints which imply an iterated variable are implemented using a set of several filtering methods. Each of this method is intended to reduce the domain of the iterated variable in a given context. The general principal is the following. Let C R(v, v*) be a temporal constraint which imposes hat the values of the two variables v and v* are in the R temporal relation, v* being an iterated variable, v being either iterated or not. When v is instantiated, i.e. when the solver chooses a value for v, some filtering methods are called which suppress from the domain of v* the iterated sequences which don’t respect the R relation.Let us take as example a template which specifies that a jingle must precisely meets an iterated sequence of shots. The meets relation is expected to be frequently encountered in templates, and thus a specialized filtering method has been designed for it. The v J variable represents the jingle and the v S* variable represents the shot sequence. The observations are illustrated by Figure 8. During the recognition process, the solver may choose to affect the jingle-1 to v J. In this case, the doMeets filtering method is called, which suppresses from the domain of v s*. all the sequences which don’t start with the sixth shot, as illustrated in the figure. Similar methods are designed for other cases which are expected to frequently happen, as the starts, equals or finishes temporal relations.Another set of 13 methods are designed to cope with any temporal constraint, one for each of the Allen’s basic temporal relation. For the r Allen’s basic relation, the filtering method doNot-r is implemented, which takes as argument an iterated variables v* and an observed event e, and which suppresses from the domain of v* all the sequences which are in the r relation with e. In order to process a C R(v, v*) constraint in the case where R is any disjunction of Allen’s basic relations, the doNot-r method is called for all the Allen’s basic relation r which are not part of R.Figure 8: filtering iterated variablesTemplate subsumptionIt would be appreciable if the template library was hierarchically organized according to subsumption links, as are concepts in a taxonomy. In (Weida, 1995), recognizing instances of templates among theobservations amounts to testing subsumption between templates, as plans and observations are roughly the same kind of temporal constraint networks. Unfortunately, the iteration operator we introduce in the template definition language results in an important complexity in the computation of subsumption between templates, as the ‘*’ may appear in both the subsuming and the subsumee template. This implies that computing subsumption would necessitate to find a matching from sub-networks of the subsuming constraint network to sub-networks of the subsumee constraint network. Consider for example the templates T1 and T2 illustrated by Figure 9. T1 subsumes T2, as any set of observations recognized as an instance of T2 would also be recognized as an instance of T1.Figure 9: templates subsumptionExperimentationWe present in this section some experimentation we made on different broadcast news. Some of the documents come from an annotated corpus which was provided by INA and the AIM3 group, the other are part of the corpus of the DiVAN project. The results presented here rely on reference segmentations established for evaluation of analysis and classification tools of the DiVAN project (Bouthemy et al., 1999). The newscasts presented here fall into two main categories: • Traditional newscasts, alternating between the anchor person in the studio, and pre-recorded stories;• Short newscasts composed of a small set of pre-recorded stories separated by jingles and/or graphics.In order to recognize reports from this two types of newscast, two different methods are used which use different templates. It should be noted that similar classes of events – similar concepts – in two different newscast may have different definitions at the signal level. For example, the name of a character being filmed appears differently in a “Soir 3” and in a “France 2” evening newscasts, as well as the place of the logo is different (see Figure 3 above and Figure 10 below).Reports of “France 2” newscastIn an edition of the “France 2” evening newscast, report sequences alternate with shots showing the anchorman in a studio. The anchorman can be filmed from different cameras. The logo of the channel always appear during report sequences on the bottom right of the screen, and never appears on studio shots, except once4. During report sequences, a text inscription on the bottom left of the screen always indicates the name of the person being filmed as a text inscription on the bottom right of a medium close-up shot always indicates the name of the location where the action takes place. Detecting these types of shots is interesting for at least two reasons. First, it may help to temporally structure the report sequence itself. Second, these shots may be used for summarize the report sequence, by for instance preferably select keyframes coming from these shots.By exploiting the results of three analysis tools, namely a logo, a text region and a face region detection tool, four classes of shots can be defined for this newscast. These four classes are illustrated by Figure 10 and are organized according to subsumption links as shown in the figure.3 Action Indexation Multimedia4 We do not take this shot into account here。