Review on embankment dam breach modeling

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Sediment Transport Modeling Review—Current and

Sediment Transport Modeling Review—Current andFuture DevelopmentsAthanasios N.͑Thanos ͒PapanicolaouAssociate Professor,Univ.of Iowa,IIHR-Hydroscience and Engineering,Dept.of Civil and Environmental Engineering,Iowa City,IA 52241.E-mail:apapanic@Mohamed ElhakeemResearch Associate Engineer,Univ.of Iowa,IIHR-Hydroscience and En-gineering,Dept.of Civil and Environmental Engineering,Iowa City,IA 52241.E-mail:melhakee@George KrallisERM Inc.,Exton,PA.E-mail:george.krallis@Shwet PrakashERM Inc.,Exton,PAJohn EdingerFaculty Research Associate,Bryn Mawr College,Dept.of Geology.E-mail:jeedgr@IntroductionThe use of computational models for solving sediment transport and fate problems is relatively recent compared with the use of physical models.Several considerations govern the choice be-tween physical and computational models;namely,the nature of the problem that needs to be solved,the available resources,and the overall cost associated with the problem solution.In some speciﬁc problems,a combination of physical and computational models can be used to obtain a better understanding of the pro-cesses under investigation ͑de Vries 1973͒.Using computational hydrodynamic/sediment transport models,in general,involves the numerical solution of one or more of the governing differential equations of continuity,momentum,and energy of ﬂuid,along with the differential equation for sediment continuity.An advan-tage of computational models is that they can be adapted to dif-ferent physical domains more easily than physical models,which are typically constructed to represent site-speciﬁc conditions.An-other advantage of computational models is that they are not sub-ject to distortion effects of physical models when a solution can be obtained for the same ﬂow conditions ͑identical Reynolds and Froude numbers,same length scale in the three directions,etc.͒as those present in the ﬁeld.With the rapid developments in numerical methods for ﬂuid mechanics,computational modeling has become an attractive tool for studying ﬂow/sediment transport and associated pollutant fate processes in such different environments as rivers,lakes,and coastal areas.Representative processes in these environments in-clude bed aggradation and degradation,bank failure,local scour around structures,formation of river bends,ﬁning,coarsening and armoring of streambeds,transport of point source and nonpointsource pollutant attached to sediments,such sediment exchange processes as settling,deposition,and self-weight consolidation;coastal sedimentation;and beach processes under tidal currents and wave action.Over the past three decades,a large number of computational hydrodynamic/sediment transport models have been developed ͑Fan 1988;Rodi 2006͒.Extensive reviews of different hydrodynamic/sediment transport models can be found in Nicollet ͑1988͒,Nakato ͑1989͒,Onishi ͑1994͒,Przedwojski et al.͑1995͒,Spasojevic and Holly ͑2000͒,and the ASCE Sedimentation Engi-neering Manual no.110͑2007͒.Broadly speaking,these models can be classiﬁed on the basis of the range of their applications ͑e.g.,suspended load versus bed-load;physical versus chemical transport ͒;and their formulation in the spatial and temporal con-tinua ͑e.g.,one-dimensional model ͑1D ͒;two-dimensional model ͑2D ͒;or three-dimensional model ͑3D ͒;and steady versus un-steady ͒.The choice of a certain model for solving a speciﬁc prob-lem depends on the nature and complexity of the problem itself,the chosen model capabilities to simulate the problem adequately,data availability for model calibration,data availability for model veriﬁcation,and overall available time and budget for solving the problem.The objectives of this article are twofold.First,the article aims to trace the developmental stages of current representative ͑1D,2D,and 3D ͒models and describe their main applications,strengths,and limitations.The article is intended as a ﬁrst guide to readers interested in immersing themselves in modeling and at the same time sets the stage for discussing current limitations and future needs.Second,the article provides insight about future trends and needs with respect to hydrodynamic/sediment transport models.In preparing this article,the authors may have uninten-tionally omitted some models,since including all the available models found in the literature is impossible.Finally,this article is mainly focused on multidimensional computational models ͑2D and 3D models ͒;however,a brief overview of the 1D models is also included for providing a rational comparison of the 1D model features with the main features of the 2D and 3D models.Description of ModelsThis section provides information about the model formulation,the spatial and temporal characteristics,the coupling/linkage of the hydrodynamic and sediment components,and the model’s predictive capabilities.Tables 1–3complement this description by providing useful information about the model capabilities to handle unsteady ﬂows,bed load and suspended load,sediment exchange processes,type of sediment ͑cohesive versus cohesion-less ͒,and multifractional sediment rmation about model acronyms,language,availability,and distribution is also provided in Tables 1–3.Tables 4–6summarize examples of the different model applications.The reader can use these case stud-JOURNAL OF HYDRAULIC ENGINEERING ©ASCE /JANUARY 2008/1D o w n l o a d e d f r o m a s c e l i b r a r y .o r g b y Z h e j i a n g U n i v e r s i t y o n 01/26/13. C o p y r i g h t A S CE .F o r p e r s o n a l u s e o n l y ; a l l r i g h t s r e s e r v e d .ies as a reference guide for model setup,calibration,and veriﬁ-cation.One-Dimensional ModelsSince the early 1980s,1D models have been used with some success in research and engineering practice.Most of the 1D models are formulated in a rectilinear coordinate system and solve the differential conservation equations of mass and momen-tum of ﬂow ͑the St.Venant ﬂow equations ͒along with the sedi-ment mass continuity equation ͑the Exner equation ͒by using ﬁnite-difference schemes.Some representative models that are developed on the basis of the previously mentioned equations include MOBED by Krishnappan ͑1981͒,IALLUVIAL by Karim and Kennedy ͑1982͒,CHARIMA by Holly et al.͑1990͒,SEDI-COUP by Holly and Rahuel ͑1990͒,3ST1D by Papanicolaou et al.͑2004͒.The HEC-6formulation by Thomas and Prashum ͑1977͒is also presented in a rectilinear coordinate and is dis-cretized by using ﬁnite-difference schemes;but it solves the differential conservation equation of energy instead of the mo-mentum equation.Among other 1D models that use different coordinate systems,equations or schemes of solution are FLUVIAL 11by Chang ͑1984͒,GSTARS by Molinas and Yang ͑1986͒,and OTIS by Runkel and Broshears ͑1991͒.Chang ͑1984͒used a curvilinear coordinate system to solve the governing equations of his model.Molinas and Yang ͑1986͒implemented the theory of minimum stream power to determine the optimum channel width and ge-ometry for a given set of hydraulic and sediment conditions.Runkel and Broshears ͑1991͒modiﬁed the 1D advection-diffusion equation with additional terms to account for lateral inﬂow,ﬁrst-order decay,sorption of nonconservative solutes,and transient storage of these solutes.Most of the 1D models that are presented here can predict the basic parameters of a particular channel,including the bulk-velocity,water surface elevation,bed-elevation variation,and sediment transport load.All of them,except OTIS,can also pre-dict the total sediment load and grain size distribution of nonuni-form sediment.3ST1D by Papanicolaou et al.͑2004͒cannot differentiate the total sediment load into bed load and suspended load.HEC-6by Thomas and Prashum ͑1977͒and IALLUVIAL by Karim and Kennedy ͑1982͒are not applicable to unsteady ﬂow conditions.Table 1contains the complete model reference and acronym explanation and summarizes the main features for each model.Some of these 1D models have additional speciﬁc features.HEC-6by Thomas and Prashum ͑1977͒,for example,decom-poses energy losses into form loss and skin friction loss.MOBED by Krishnappan ͑1981͒can predict the sediment characteristics of a streambed as a function of time and distance for different ﬂow hydrographs.FLUVIAL 11by Chang ͑1984͒accounts for the presence of secondary currents in a curved channel by adjusting the magnitude of the streamwise velocity.The same model can predict changes in the channel bed proﬁle,width,and lateral mi-gration in channel bends.CHARIMA by Holly et al.͑1990͒andHEC-6:Hydraulic Engineering Center;Thomas and Prashum ͑1977͒V .4.2͑2004͒Steady Yes Yes Yes No Entrainment and deposition PDPDF77MOBED:MObile BED;Krishnappan ͑1981͒—Unsteady Yes Yes Yes No Entrainment and deposition C C F90IALLUVIAL:Iowa ALLUVIAL;Karim and Kennedy ͑1982͒—Quasi-steady Yes Yes Yes No Entrainment and deposition C C FIV FLUVIAL 11;Chang ͑1984͒—Unsteady Yes Yes Yes No Entrainment and deposition C P FIV GSTARS:Generalized sediment transport models for alluvial River simulation͑Molinas and Yang,1986͒V .3͑2002͒Unsteady Yes Yes Yes No Entrainment and deposition PDPDF90/95CHARIMA:Acronym of the word CHARiage which means bedload in FrenchHolly et al.͑1990͒—Unsteady Yes Yes Yes Yes Entrainment and deposition C C F 77SEDICOUP:SEDIment COUPled;Holly and Rahuel ͑1990͒—Unsteady Yes Yes Yes No Entrainment and deposition C C F77OTIS:One-dimensional transport with inﬂow and storage;Runkel and Broshears ͑1991͒V .OTIS-P ͑1998͒Unsteady No Yes No No Advection-diffusion PDPDF 77EFDC1D:Environmental ﬂuid dynamics code;Hamrick ͑2001͒—Unsteady Yes Yes Yes Yes Entrainment anddeposition PD PD F773STD1,steep stream sediment Transport 1D model;Papanicolaou et al.͑2004͒—Unsteady a Yes aYes Yes No Entrainmentand deposition C P F90Note:V ϭversion;C ϭcopyrighted;LD ϭlimited distribution;P ϭproprietary;PD ϭpublic domain;and F ϭFORTRAN.aTreated as a total load without separation.2/JOURNAL OF HYDRAULIC ENGINEERING ©ASCE /JANUARY 2008D o w n l o a d e d f r o m a s c e l i b r a r y .o r g b y Z h e j i a n g U n i v e r s i t y o n 01/26/13. C o p y r i g h t A S CE .F o r p e r s o n a l u s e o n l y ; a l l r i g h t s r e s e r v e d .OTIS by Runkel and Broshears ͑1991͒can treat transport and fate of conservative contaminants and heat.EFDC1D by Hamrick ͑2001͒can be applied to stream networks.3ST1D by Papanico-laou et al.͑2004͒is capable of capturing hydraulic jumps and simulating supercritical ﬂows;therefore,it is applicable to un-steady ﬂow conditions that occur over transcritical ﬂow stream reaches,such as ﬂows over step-pool sequences in mountain streams.Because of their low data,central processor unit ͑CPU ͒re-quirements,and simplicity of use,1D models remain useful pre-dictive tools even today,especially in consulting,for rivers and stream ecological applications where 2D or 3D models may not be needed and are computationally expensive.Table 4presents examples of different 1D model applications.Two-Dimensional ModelsSince the early 1990s,there has been a shift in computational research toward 2D models.Most of the 2D models are currently available to the hydraulic engineering community as interface-based software to allow easy data input and visualization of re-sults.This added capability has made these models user-friendly and popular.2D models are depth-averaged models that can pro-vide spatially varied information about water depth and bed elevation within rivers,lakes,and estuaries,as well as the mag-nitude of depth-averaged streamwise and transverse velocity com-ponents.Most 2-D models solve the depth-averaged continuity and Navier-Stokes equations along with the sediment mass bal-ance equation with the methods of ﬁnite difference,ﬁnite element,or ﬁnite volume.Table 2shows the complete model reference and explanation of the model acronym and summarizes the characteristics of selected 2D hydrodynamic/sediment trans-port models.The main speciﬁc features of each model are de-scribed below:SERATRA:A ﬁnite-element sediment-contaminant transport model developed by Onishi and Wise ͑1982͒.The model includes general advection-diffusion equations and incorporates sink/source terms.The model can predict overland ͑terrestrial ͒and in-stream pesticide migration and fate to assess the potential short-and long-term impacts on aquatic biota in receiving streams.SUTRENCH-2D:A ﬁnite-volume hydrodynamic and sediment transport model developed by van Rijn and Tan ͑1985͒for simu-SERATRA:SEdiment and RAdionuclide TRAnsport;Onishi and Wise ͑1982͒—Unsteadya Yes a Yes No Yes Advection-diffusion CC/LDFIVSUTRENCH-2D:SUspended sediment transport in TRENCHes;van Rijn and Tan ͑1985͒—Quasisteadya Yes a Yes No No Advection-diffusion C LD F90TABS-2;Thomas and McAnally ͑1985͒—Unsteadya Yes a Yes No Yes Entrainment and deposition C C F77MOBED2:MObile BED;Spasojevic and Holly ͑1990a ͒—Unsteady Yes Yes Yes No Entrainment and depositionC C F77ADCIRC:ADvanced CIRCulation;Luettich et al.͑1992͒—Unsteady a Yes aYes No Yes Advection-diffusionC/LD C/LD F90MIKE 21:Danish acronym of the word microcomputer;Danish Hydraulic Institute ͑1993͒—Unsteady a Yes aYes No Yes Entrainment and deposition CPF90UNIBEST-TC:UNIform BEach Sediment Transport—Transport Cross-shore;Bosboom et al.͑1997͒—Quasi-steadya Yes a Yes No No Entrainment and advection C LD F90USTARS:Unsteady Sediment Transport models for Alluvial Rivers Simulations;Lee et al.͑1997͒—Unsteady Yes Yes Yes No Entrainment and deposition P P F90FAST2D:Flow Analysis Simulation Tool;Minh Duc et al.͑1998͒—Unsteady Yes Yes No No Entrainment and deposition LD P F90FLUVIAL 12;Chang ͑1998͒—Unsteady Yes Yes Yes No Entrainment and deposition C P F77Delft 2D;Walstra et al.͑1998͒—Unsteady Yes Yes No Yes Advection-diffusion C LD F90CCHE2D:The National Center for Computational Hydroscience and Engineering;Jia and Wang ͑1999͒V .2.1͑2001͒Unsteady Yes Yes Yes No Advection-diffusion PD/CLDF77/F90Note:V ϭversion;C ϭcopyrighted;LD ϭlimited distribution;P ϭproprietary;PD ϭpublic domain;F ϭFORTRAN.aTreated as a total load without separation.JOURNAL OF HYDRAULIC ENGINEERING ©ASCE /JANUARY 2008/3D o w n l o a d e d f r o m a s c e l i b r a r y .o r g b y Z h e j i a n g U n i v e r s i t y o n 01/26/13. C o p y r i g h t A S CE .F o r p e r s o n a l u s e o n l y ; a l l r i g h t s r e s e r v e d .lating sediment transport and associated bed level change under conditions of combined quasi-steady currents and wind-induced waves over a sediment bed.The model solves the general advection-diffusion equations by incorporating a lag coefﬁcient to account for the settling of sediments.TABS-2:A group of ﬁnite-element based hydrodynamic and sediment transport computer codes developed by the USACE Wa-terways Experimental Station ͑Thomas and McAnally 1985͒that currently operates by using the SMS v.9.0windows interface.These codes are applicable to rivers,reservoirs,and estuaries.The main components of TABS-2are the hydrodynamic component,RMA2;the sediment transport component,SED2D ͑formally STUDH ͒;and the water quality component,RMA4.MOBED2:A ﬁnite-difference hydrodynamic and sediment transport model used in a curvilinear coordinate system,devel-oped by Spasojevic and Holly ͑1990a ͒.The model can simulate water ﬂow,sediment transport,and bed evolution in natural wa-terways such as reservoirs,estuaries,and coastal environments where depth averaging is appropriate.ADCIRC-2D:A ﬁnite-element hydrodynamic and sediment transport model developed by Luettich et al.͑1992͒in a rectilin-ear coordinate system for simulating large-scale domains ͑e.g.,the entire East Coast of the United States ͒by using 2D equationsfor the “external mode”but using the “internal mode”for obtain-ing detailed velocity and stress at localized areas.The internal mode is achieved by specifying the momentum dispersion and the bottom shear stress in terms of the vertical velocity proﬁle.The wave-continuity formulation of the shallow-water equations is used to solve the time-dependent,free-surface circulation and transport processes.MIKE2:A ﬁnite-difference model in a rectilinear coordinate system developed by the Danish Hydraulic Institute ͑1993͒for simulating transport and fate of dissolved and suspended loads discharged or accidentally spilled in lakes,estuaries,coastal areas,or in the open sea.The system consists of four main model groups ͑modules ͒,namely,the hydrodynamic and wave models,the sediment process model,and the environmental hydrody-namic model groups.The hydrodynamic and wave models are relevant to the types of physical processes considered in ﬂood-plain mapping.The sediment process models are used to simulate shoreline change and sand transport,whereas the environmental hydrodynamic models are used to examine water quality issues.UNIBEST-TC2:A ﬁnite-difference hydrodynamic and sedi-ment transport model in a rectilinear coordinate system to de-scribe the hydrodynamic processes of waves and currents in the cross-shore direction by assuming the presence of uniform meanECOMSED:Estuarine,Coastal,and Ocean Model—SEDiment transport;Blumberg and Mellor ͑1987͒V .1.3͑2002͒Unsteady aYesaYes No YesEntrainment and deposition PDPDF77RMA-10:Resource Management Associates;King ͑1988͒—Unsteady aYesaYes No Yes Entrainment and deposition C P F77GBTOXe:Green Bay TOXic enhancement;Bierman et al.͑1992͒—Unsteady No Yes No Yes Entrainment and deposition NA NA F77EFDC3D:Environmental Fluid Dynamics code;Hamrick ͑1992͒—Unsteady Yes Yes Yes Yes Entrainment and deposition PD P F77ROMS:Regional Ocean Modeling System;Song and Haidvogel ͑1994͒V .1.7.2͑2002͒Unsteady Yes Yes Yes No Entrainment and deposition LD LD F77CH3D-SED:Computational Hydraulics 3D-SEDiment;Spasojevic and Holly ͑1994͒—Unsteady Yes Yes Yes Yes Entrainment and deposition C C F90SSIIM:Sediment Simulation In Intakes with Multiblock options;Olsen ͑1994͒V .2.0͑2006͒Steady Yes Yes Yes No Advection-diffusion PD P C-Langua.MIKE 3:Danish acronym of the word Microcomputer;Jacobsen and Rasmussen ͑1997͒—Unsteady aYesaYes No Yes Entrainment and deposition C P F90FAST3D:Flow Analysis Simulation Tool;Landsberg et al.͑1998͒V .Beta-1.1͑1998͒Unsteady Yes Yes No No Entrainment and depositionLD P F90Delft 3D;Delft Hydraulics ͑1999͒V .3.25.00͑2005͒Unsteady Yes Yes No Yes Entrainment anddepositionC LD F77TELEMAC;Hervouet and Bates ͑2000͒—Unsteady a Yes a Yes No Yes Entrainment anddepositionC P F90Zeng et al.͑2005͒—UnsteadyYes Yes No No Entrainment anddepositionPPF90Note:V ϭversion;C ϭcopyrighted;LD ϭlimited distribution;P ϭproprietary;PD ϭpublic domain;F ϭFORTRAN.aTreated as a total load without separation.4/JOURNAL OF HYDRAULIC ENGINEERING ©ASCE /JANUARY 2008D o w n l o a d e d f r o m a s c e l i b r a r y .o r g b y Z h e j i a n g U n i v e r s i t y o n 01/26/13. C o p y r i g h t A S CE .F o r p e r s o n a l u s e o n l y ; a l l r i g h t s r e s e r v e d .longshore currents along the beach ͑Bosboom et al.1997͒.The bed load and suspended load transport processes are modeled by assuming local equilibrium conditions ͑no lag effects are consid-ered between ﬂow and sediment ͒.USTARS:A modiﬁed form of ͑GSTARS ͒that is also based on the stream tube concept ͑Lee et al.1997͒.The hydrodynamic and sediment equations are solved with a ﬁnite-difference scheme in a rectilinear coordinate system.As in GSTARS,the theory of mini-mum stream power is used here to determine the optimum chan-nel width and geometry for a given set of hydraulic,geomorpho-logic,sediment,and man-made constraints.FAST2D:A ﬁnite-volume hydrodynamic and sediment model with boundary-ﬁtted grids in a curvilinear coordinate system to simulate sediment transport and morphodynamic problems in al-luvial channels ͑Minh Duc et al.1998͒.The model accounts in-directly for secondary effects attributed to the complexity of the domain.FLUVIAL 12:A ﬁnite-difference hydrodynamic and sediment model in a curvilinear coordinate system developed by Chang ͑1998͒.The combined effects of ﬂow hydraulics,sediment trans-port,and river channel changes can be simulated for a given ﬂow period.The model is a mobile-bed model and simulates changes in the channel-bed proﬁle,width,and sediment bed composition induced by the channel curvature.DELFT-2D:A ﬁnite-difference hydrodynamic and sediment transport model simulating waves and currents ͑Walstra et al.1998͒.The model couples the hydrodynamics with computed bot-tom morphological changes in a time-dependent way.The model can simulate bed-load and suspended load transport by using ei-ther a local equilibrium or a nonequilibrium ͑i.e.,the lag effects between ﬂow and sediment ͒approach.The model can also show the effects of wave motion on transport magnitude and HE2D:A ﬁnite-element hydrodynamic and sediment model developed by Jia and Wang ͑1999͒.The model simulates the sus-pended sediment by solving the advection-diffusion equation and the bed-load transport by empirical functions ͑e.g.,Yalin 1972;van Rijn 1993͒.The model accounts for the secondary ﬂow effect in curved channels.All the aforementioned models are applicable to unsteady ﬂow conditions,except SUTRENCH-2D by van Rijn and Tan ͑1985͒and UNIBEST-TC2by Bosboom et al.͑1997͒.All models can predict the total sediment transport load;but only MOBED2,USTARS,FLUVIAL 12,and CCHE2D can handle multifrac-tional sediment transport and can decompose the total sediment load into bedload and suspended load.DELFT-2D and FAST2D can also separate the total sediment load into bedload and sus-HEC-6;Thomas and Prashum ͑1977͒Prediction of the ﬂow and sediment transport along with the bed level change of the Saskatchewan River below Gardiner Dam,Canada ͑Krishnappan 1985͒Prediction of the bed proﬁle for the eroded and redeposited delta sediment upstream from Glines Canyon Dam,Washington ͑U.S.Department of Interior,Bureau of Reclamation 1996͒MOBED;Krishnappan ͑1981͒Comparison of MOBED results with HEC-6results for the ﬂow and sediment transport along with the bed-level change for the Saskatchewan River below Gardiner Dam,Canada ͑Krishnappan 1985͒Prediction of ﬁne sediment transport under ice cover in the Hay River in Northwest Territories,Canada IALLUVIAL;Karim and Kennedy ͑1982͒Simulation of ﬂow and sediment processes in the Missouri River,Nebraska ͑Karim and Kennedy 1982͒Simulation of ﬂow and sediment processes downstream of the Gavins Point Dam on the Missouri River,Nebraska ͑Karim 1985͒FLUVIAL 11;Chang ͑1984͒Simulation of ﬂow and sediment processes of the San Dieguito River,Southern California ͑Chang 1984͒Simulation of ﬂow and sediment processes of the San Lorenzo River,Northern California ͑Chang 1985͒GSTARS;Molinas and Yang ͑1986͒Prediction of the scour depth and pattern at the Lock and Dam No.26replacement site on the Mississippi River,Illinois ͑Yang et al.1989͒Prediction of the variation in channel geometry for the unlined spillway downstream Lake Mescalero Reservoir,New Mexico ͑Yang and Simões 2000͒CHARIMA;Holly et al.͑1990͒Mobile-bed dynamics in the Missouri River from Ft.Randall to Gavins Point Dam,South Dakota ͑Corps of Engineers ͒Mobile-bed dynamics in the Missouri River from Gavins Point Dam to Rulo,Nebraska ͑National Science Foundation ͒SEDICOUP;Holly and Rahuel ͑1990͒Modeling of long-term effects of rehabilitation measures on bed-load transport at the Lower Salzach River,Germany ͑Otto 1999͒Long-term modeling of the morphology of the Danube River,Germany ͑Belleudy 1992͒OTIS;Runkel and Broshears ͑1991͒Simulation of ﬁeld experiments conducted by Bencala and Walters ͑1983͒for the change in chloride concentration of the Uvas Creek,California.Estimation of the travel times and mixing characteristics of the Clackamas River,Oregon,using the slug of rhodamine data of Laenen and Risley ͑1997͒EFDC1D;Hamrick ͑2001͒Simulation of the ﬂow and sediment transport processes in the Duwamish River and Elliott Bay,Washington ͑Schock et al.1998͒Development of a water quality model for the Christina River,Delaware ͑USEPA 2000͒3STD1;Papanicolaou et al.͑2004͒Prediction of the grain size distribution and bed morphology of the Cocorotico River,Venezuela ͑Papanicolaou et al.2004͒.Prediction of the grain size distribution and bed-load rate of the Alec River,Alaska ͑Papanicolaou et al.2006͒JOURNAL OF HYDRAULIC ENGINEERING ©ASCE /JANUARY 2008/5D o w n l o a d e d f r o m a s c e l i b r a r y .o r g b y Z h e j i a n g U n i v e r s i t y o n 01/26/13. C o p y r i g h t A S CE .F o r p e r s o n a l u s e o n l y ; a l l r i g h t s r e s e r v e d .pended load,but they are limited to uniform sediment sizes.Ex-amples of the different 2D model applications are summarized in Table 5.Three-Dimensional ModelsIn many hydraulic engineering applications,one has to resort to 3D models when 2D models are not suitable for describing cer-tain hydrodynamic/sediment transport processes.Flows in the vi-cinity of piers and near hydraulic structures are examples in which 3D ﬂow structures are ubiquitous and in which 2D models do not adequately represent the physics.With the latest develop-ments in computing technology—such as computational speed,parallel computing,and data storage classiﬁcation—3D hydrodynamic/sediment transport models have become much more attractive to use.Most 3D models solve the continuity and the Navier-Stokes equations,along with the sediment mass bal-ance equation through the methods of ﬁnite difference,ﬁnite ele-ment,or ﬁnite-volume.The Reynolds average Navier-Stokes ͑RANS ͒approach has been employed to solve the governing equations.The RANS models can be separated into hydrostatic and non-hydrostatic models.The hydrostatic models ͑e.g.,Gessler et al.1999͒are not able to accurately predict ﬂow and transport phe-nomena in regions where the ﬂow is strongly 3D and where large adverse pressure gradients or massive separation are present ͑e.g.,river bends containing hydraulic structures ͒.On the contrary,non-hydrostatic RANS models have been shown to adequately de-scribe intricate features of secondary ﬂows in complex domains ͑e.g.,Wu et al.2000;Ruther and Olsen 2005͒.Table 3shows the complete model reference and explanation of the acronym and summarizes the characteristics of 12selected 3D hydrodynamic/sediment transport models.The main speciﬁc features of each model are described below:ECOMSED:A fully integrated 3D ﬁnite-difference hydrody-namic,wave,and sediment transport model in an orthogonal cur-SERATRA;Onishi and Wise ͑1982͒Investigation of the effects of sediment on the transport of radionuclides in Cattaraugus and Buttermilk Creeks,New York ͑Walters et al.1982͒Simulation of the hydrogeochemical behavior of radionuclides released to the Pripyat and Dnieper rivers from the Chernobyl Nuclear Power Plant in Ukraine ͑V oitsekhovitch et al.1994͒SUTRENCH-2D;van Rijn and Tan ͑1985͒Simulation of sand transport processes and associated bed-level changes along dredged pits and trenches at the lower Dutch coast,The Netherlands ͑Walstra et al.1998͒Modeling sediment transport and coastline development along the Iranian coast,Caspian Sea ͑Niyyati and Maraghei 2002͒TABS-2;Thomas and McAnally ͑1985͒Simulation of the ﬂow and sediment transport processes in the Black Lake,Alaska ͑Papanicolaou et al.2006͒Evaluation of the hydraulic performance of different structures found in the Missouri River for creating new shallow water habitat ͑Papanicolaou and Elhakeem 2006͒MOBED2;Spasojevic and Holly ͑1990a ͒Simulation of mobile-bed dynamics in the Coralville Reservoir on the Iowa River,Iowa ͑Spasojevic and Holly 1990b ͒ADCIRC;Luettich et al.͑1992͒Simulation of the ﬂow and sediment transport processes of the natural cap in the Matagorda Bay,Texas ͑Edge 2004͒Simulation of sand transport processes at Scheveningen Trial Trench,The Netherlands ͑Edge 2004͒MIKE 21;Danish Hydraulic Institute ͑1993͒Prediction of the spreading of dredged spoils in the Øresund Link,Denmark-Sweden Prediction of sediment transport rate at ebb ﬂow in a tidal inlet,Grådyb,Denmark UNIBEST-TC;Bosboom et al.͑1997͒Coastal study for the impacts of constructing Kelantan Harbor,MalaysiaCoastal study for shoreline protection of Texel region,The NetherlandsUSTARS;Lee et al.͑1997͒Simulation of sand transport processes and associated bed-level changes of a reach in the Keelung River,Taiwan ͑Lee et al.1997͒Routing of ﬂow and sediment of the Shiemen Reservoir,upstream Tan-Hsui River,Taiwan ͑Lee et al.1997͒FAST2D;Minh Duc et al.͑1998͒Simulation of sediment transport processes and associated bed level changes of a reach in the Bavarian Danube River,Germany ͑Minh Duc et al.1998͒Flood analysis and mitigation on the Orlice River,Poland ͑Beck et al.2003͒FLUVIAL 12;Chang ͑1998͒Simulation of ﬂow and sediment processes of the San Dieguito River,Southern California ͑Chang 1994͒Simulation of ﬂow and sediment processes of the Feather River,Northern California ͑Chang et al.1996͒Delft 2D;Walstra et al.͑1998͒Simulation of sand transport processes and associated bed-level changes along dredged pits and trenches at the lower Dutch coast,The Netherlands ͑Walstra et al.1998͒Simulation of the ﬂow ﬁeld and sediment transport processes of the Pannerdense Kop and IJssel Kop bifurcations in the Rhine River,The Netherlands ͑Sloff 2004͒CCHE2D;Jia and Wang ͑1999͒Investigation of the effects of the rock pile and the submerged dikes downstream of the Lock and Dam No.2of the Red River Waterway,LouisianaInvestigation of the effects of large woody debris structures on the ﬂuvial processes in the Little Topashaw Creek,Mississippi ͑Wu et al.2005͒6/JOURNAL OF HYDRAULIC ENGINEERING ©ASCE /JANUARY 2008D o w n l o a d e d f r o m a s c e l i b r a r y .o r g b y Z h e j i a n g U n i v e r s i t y o n 01/26/13. C o p y r i g h t A S CE .F o r p e r s o n a l u s e o n l y ; a l l r i g h t s r e s e r v e d .。

Modeling and Optimization of the intermodal terminal Mega Hub Abstract

The fast transhipment system, the central element of the Mega Hub, has two basic functions. It serves either as a rail-to-rail transfer system between long distance trains hub function or between regional feeder trains and long distance trains, or it is used as a classical rail road transhipment terminal for local transport operations for the city and region of Hannover. The con guration of the terminal is as follows. 4 to 10 cranes span six rails for the loading and unloading of trains, a lorry loading lane for local transport operations, three storage lanes for the intermediate storage of load units and the fully automatic sorting system. A model of the terminal is shown in gure 1. Rail-to-rail transhipment by crane can take place fully automatically if certain minimum standards are observed with regard to the wagons used ensuring fast and reliable localisation of the load units on the train and if the usual practice of adjusting the wagon ttings manually is superseded by a di erent method of adjustment working safety!.

bim英语演讲 -回复

bim英语演讲-回复"bim英语演讲"Title: Revolutionizing Construction: The Power of Building Information Modeling (BIM)Introduction:Good morning/afternoon/evening, distinguished guests, faculty, and fellow students. Today, I stand before you to shed light on the revolutionary concept of Building Information Modeling, or BIM. This presentation aims to provide a comprehensive understanding of BIM, explore its application in the construction industry, and showcase the numerous benefits it brings to the table. So let's embark on this journey of digital transformation and explore the power of BIM.I. What is Building Information Modeling? (200-300 words) Building Information Modeling, commonly known as BIM, refers to a digital representation of a built environment. It creates a virtual model of a construction project, encompassing all the information about its design, materials, functions, and processes. BIM is not just a 3D visualization tool; rather, it is a collaborative process thatincorporates data and enables stakeholders to make informed decisions throughout the entire construction lifecycle.II. The Application of BIM in the Construction Industry (400-500 words)The construction industry is notoriously complex, with numerous challenges that often lead to cost overruns and delays. However, BIM has emerged as a game-changer in addressing these issues. Let's explore some key applications of BIM in the construction industry:1. Design and Visualization: BIM allows architects and designers to create detailed models, visualize the final product, and identify potential design clashes or conflicts early on. This early detection helps save both time and money.2. Clash Detection and Coordination: BIM enables different stakeholders, such as architects, engineers, and contractors, to collaborate seamlessly. Clash detection features enable identification and resolution of clashes or conflicts between various building systems, thereby ensuring seamless coordination.3. Quantity Takeoff and Cost Estimation: BIM software can automatically extract necessary information, such as quantities and specifications of materials, from the digital model. This significantly streamlines the cost estimation process, improves accuracy, and reduces the chances of human error.4. Construction Planning and Sequencing: BIM allows the creation of 4D models, combining the spatial information from the 3D model with the element of time. This helps in visualizing the construction sequence, improving site logistics, and avoiding conflicts during construction.III. Benefits of BIM (300-400 words)BIM offers numerous benefits that streamline project delivery and enhance overall construction management. Let's delve into some key advantages of implementing BIM:1. Enhanced Collaboration and Communication: BIM promotes improved communication and collaboration among project stakeholders. It creates a common platform for sharing information, allowing real-time updates and reducing the chances of miscommunication.2. Improved Accuracy and Quality: BIM models ensure accurate and reliable data throughout the project lifecycle. This leads to enhanced quality control, reduced errors, and facilitates timely decision-making.3. Risk Mitigation: BIM enables stakeholders to identify potential risks and issues at an early stage, facilitating effective mitigation strategies. This helps in avoiding costly changes, delays, and accidents onsite.4. Sustainable Design and Resource Optimization: BIM facilitates energy analysis and simulations, enabling designers to optimize a building's performance and identify opportunities for sustainable design. This helps in reducing energy consumption, minimizing waste, and preserving the environment.Conclusion:In conclusion, Building Information Modeling (BIM) has revolutionized the construction industry, providing an integrated and collaborative approach to project delivery. Its extensiveapplications, including design visualization, clash detection, cost estimation, and construction sequencing, have proven to be invaluable in streamlining construction processes. Furthermore, the benefits of enhanced collaboration, improved accuracy, risk mitigation, and sustainable design illustrate the power and importance of BIM in today's construction projects. As we move towards an increasingly digitized world, embracing BIM offers a promising future for the construction industry, where efficiency, sustainability, and quality prevail. Thank you.。

工程咨询价格现场英语常见词汇表

现场英语常见词汇表．．．．．．．．．Owner/Client/Customer/Co mpany 业主Buyer 买方Seller/vendor 卖方Licensor 专利商Licensee 专利受让方Third party 第三方Patent 专利Property/proprietory technology 专利技术Know-how 专有技术/知识Contractor 承包商Subcontractor分包商Supplier 供货商Sub-supplier 分供商Manufacturer 制造厂家Limited liability 有限责任Joint venture 合资企业Foreign-funded enterprise 外商独资企业Chairman 董事长Board of director 董事会President/ General manager 总经理Legal representative 法人Authorized representative 授权代表Power of attorney 委托书Signature 签字Official seal公章SEI-Sinopec Engineering Incorporated 中国石化工程建设公司SSEC-Sinopec Shanghai Engineering Company 中国石化上海工程公司SNEC-Sinopec Ningbo Engineering Company 中国石化宁波工程公司TCC-Tianchen Chemical Engineering Company 中国天辰化学工程公司HQCEC- HuanqiuContracting & EngineeringCorp.中国寰球化学工程公司LPEC-LuoyangPetrochemical EngineeringCompany 洛阳石油化工工程公司LDI-Sinopec LanzhouDesign Institute 中国石化兰州设计院Chengda ChemicalEngineering Company 中国成达化学工程公司Hualu Engineering Company中国华陆工程公司Aker Kvaerner 克瓦纳（英）Bechtel 柏克德（美）AMEC 阿美科（英）Fluor 福陆（美）Foster Wheeler 福斯特惠勒（美）Technip 德西尼布（法）TR-Técnicas Reunidas联合技术公司（西班牙）JGC 日晖（日）Toyo 东洋（日）ABB Lummus ABB鲁玛斯（美）SINOPEC 中石化CNOOC中海油PETROCHINA 中石油EXXONMOBIL 埃克森美孚（美）SHELL 英荷壳牌BP 英国石油（英）BASF 巴斯夫（德）Chevron 雪佛龙（美）Dow Chemical 陶氏化学（美）Sumitomo 住友（日）Saudi Aramco 沙特阿美（沙特）UOP 环球油品公司（美）Project/Work项目/工程Rabigh DevelopmentProject 拉比格炼油项目Location 未置/地点Onshore/domestic 国内、国产Offshore/overseas 国外、进口Plant 装置Facility 设施Unit 装置/单元Permanent/temporary work永久工程/临时工程Project/Plant/Job/Construction Site现场Battery limit 界区/红线Fence 围墙Embankment/bund 围堤Containment 围护Retaining wall 挡土墙Onsite/ISBL-InsideBattery Limit 场内Offsite/OSBL-OutsideBattery Limit 场外Contract/agreement 合同/协议Memorandum ofUnderstanding 谅解备忘录Letter of Intent意向书Original 原件/正本Copy 复印件/副本Duplicate 一式两份Triplicate一式三份Quadruplicate一式四份Quintuplicate一式五份Sextuplicate一式六份Septuplicate一式七份Octuplicate一式八份Nonuplicate一式九份Decuplicate一式十份Blueprint 蓝图Distribution 分发Holder 持有人Transmittal 文件传送单Controlled copy 受控版本Uncontrolled copy 非受控版本Edition 版本Revision 版次、修订版Terms and conditions 条款General conditions 通用条款Special conditions 特殊条款Sign/Execute/Enter into 签署Come into force/effect生效Effective Date 生效日期Contract term 和同期Expiration 届满、到期Termination 提前终止Obligation 义务Liability（债务）责任Performance 执行、业绩Breach 违约Default 失职Negligence 疏怠职责Remedy 救济、补救Compensation 补偿Performance guarantee 性能保证Waiver 放弃/弃权Severability 可分割性Modification/Change/Varia tion/Change Order 变更/变更单Amendment 修订Supplement/Addition/Adde ndum增加/增补Deletion删除Governing law 管辖法律Assignment/transfer 转让Insurance 保险Worker’s compensation 工伤责任险Employer’s liability 雇主责任险All-loss liability 一切损失险Policy保单Insurance certificate 保险证书/凭证QA-Quality Assurance质保QC/Quality Control 质控Procurement and supply 采购供应Schedule and progresscontrol 工期与进度控制Reporting 报告Acceptance 验收Spare part 备件Rework 返工Repair 修补/修复/修理Replacement 更换Substitute 替换/代用Warranty Period 保质期Claim 索赔HSE-Health, Safety andEnvironmental 健康、安全与环境HSSE- Health, Safety,Security & Environmental健康、安全与环境Taxes 税款Liquidated damages 违约赔偿Invoicing 发票Payment 付款Intellectual property right知识产权Confidentiality 保密Disclosure 披露Prior oral/written consent事先口头/书面同意Publication 公开/宣传Suspension 停工Take-over/hand-over 交工Force Majeure 不可抗力Lien 留置（权）Withhold/retention 扣缴款Dispute resolution 争议解决Arbitration 仲裁Notice 通知Courier 快递DHL/FedExpress/UPS/TNT 敦豪（德）/联邦快递（美）/环球快递（美）/荷兰邮政快递（荷兰）/EMS中国邮政特快专递Subcontract 分包/分包合同Specification 标准、规范Code/norm 规范Standard/criterion 标准Reference 参考文件Definition （术语）定义Manufa cturer’sInstruction/Recommendations 制造厂家说明/建议Operation & MaintenanceManual 操作维修手册ISO-国际标准化组织GB-中国国标ANSI-American NationalStandard Institute 美国国家标准BS-英国国家标准AFNOR-法国标准JIS-日本工业标准DIN-德国工业标准ASME-美国机械工程师学会ASTM-美国材料试验学会API-美国石油学会EPC-Engineering,Procurement andConstruction工程设计、采购与施工EP-Engineering andProcurement 工程设计与采购PMC-Project ManagementContractor 项目管理承包商CM-ConstructionManagement 施工管理CS-ConstructionSupervision监理C-Construction 施工Turnkey 交钥匙Contract price 合同价款Settlement/Accounting结算Lump sum price 总包价Fixed price 固定价Reimbursable price 补偿价Unit rate 单价ITB-Invitation to Bid 招标文件RFP-Request for Proposal 招标文件RFQ-Request for Quotation 询价文件Appendix/Annex/Attachme nt/Exhibit/Schedule 附录/附件/附表BOQ-Bill of Quantity 工程量表MTO-Material Takeoff 料表Tender/Bidder 招标人/投标人Inquiry 询价Proposal 标书Technical proposal 技术标Commercial proposal 商务标Total 合计Subtotal 小计Grand total 总计Deviation/Exception 偏差/例外Closing date 截标日期Evaluation 评标Contract award 合同授予Successful bidder 中标人Negotiation 谈判Site visit 现场参观/勘查Visitor 来访人员Pass/badge/ID Card通行证/胸牌/身份证FEED-Front End Engineering Design 前端工程设计FEL-Front End Loading 扩初设计Basic design 基本设计Detail design 详细设计PDP-Process Design Package 工艺设计包BDP-Basic Design Package基础设计包Generallayout/arrangement/Plotplan总平面布置Title block标题栏Scale比例尺/刻度/地磅Legend 图例Plan 平面图Elevation 立视图/标高Section 剖面图View 视图Detail 详图Typical 标准图Sketch 草图、简图Shop drawing 车间制造详图P&ID-Piping & InstrumentDiagram 管道仪表流程图Isometric drawing （管道）单线图Hook-up 接线图Flow sheet/diagram/chart流程图Issued for ITB 用于招标Issued for Review/Approval用于审核/批准Issued for Comments 用于征求意见Approved for construction批准用于施工Temporaryfacilities/utilities 临时设施/公用设施Deliverable交付文件/交付项Organization 组织机构Organization chart 组织机构图Responsibility matrix 责任矩阵Key personnel 关键人员Resume/CV 简历Proposed position 拟推荐职位Name 姓名Sex 性别Nationality国籍/民族Date of birth 出生日期Place of birth 出生地Address地址Education 教育/学历Work experience 工作经历FCC-No.4 constructioncompany SINOPEC/FluidCatalytic Cracking 中国石化集团第四建设公司/流化催化裂化Project management team项目部IPMT-IntegratedProject Management Team一体化项目管理部Functional department 职能部门Project Manager/Director项目经理/主任Deputy Project Manager 项目副经理Chief Engineer总工程师AdministrativeDepartment/division 行政部ConstructionDepartment/Division 施工部Project ControlDepartment/Division 项目控制部Supply & ProcurementDepartment/Division 采购供应部Quality Department 质量部HSE Department 安全部Financial Department 财务部HR-Human resources 人力资源Job team 施工队Foreman 工长/班长Technical title 技术职称Senior engineer 高工Engineer 工程师Assistant engineer 助工Trainee 实习生Employee/Staff member 员工Technical supervisor 施工员Direct manpower 直接人工Indirect manpower 间接人工Manhour人工时Craftsman 技工Craft/trade 工种Skilled worker 熟练工人Helper 力工Carpenter 木工Rebar fitter 钢筋工Pipe fitter 管工Bricklayer 瓦工Concrete worker 混凝土工Surveyor 测量员Scaffolder 架子工Welder 焊工Mechanical operator 机械操作人员Iron worker 铆工Rigger 起重工Locksmith/riveter/mechani c 钳工NDT worker 探伤工Painter 油漆工Insulator 保温工Material handler 材料搬运工Electrician 电工Instrument worker仪表工Overhead 一般管理费用Profit 利润Income tax 所得税Work Execution Plan 施工组织设计/项目执行计划Statement of Methodology 施工方案Procedure 规程、程序Plan 计划、方案Submittal 递交（文件）Review 审核Approval 批准Preparation/development编制Index / Table of Contents目录Commencement 开工Kick-off meeting 开工会Groundbreaking ceremony动工仪式Survey 勘查Bench marks 基准点Mobilization 进场Demobilization 出场Construction equipment 施工设备Manpower Histogram人工直方图Construction schedule 施工进度计划Barchart schedule 横道图Network schedule 网络图Critical path 关键路径、统筹法Milestone dates 里程碑/关键控制点日期Activities 作业活动Early start 开工日期Early finish 完工日期Duration 工期Target/objective 目标Primavera ProjectPlaner---P3Monthly/weekly report 月报/日报Statistics 统计数据Float 浮点、时间差Master/Level 1,2,3,4schedule 总体/一、二、三、四级进度计划Look-ahead schedule 滚动计划Progress 进度S curve 进度曲线Planned/Actual/Forecast计划/实际/预计Cut-off date 截止日期Weighting point 加权点Status 状态Update 更新WBS-Work BreakdownSystem 工程分解系统CBS-Cost BreakdownSystem 费用分解系统Progress measurement 进度测量Coordination 协调/调度Liaison/Contact 联系人Recovery 赶工Acceleration 加快进度Shift work 倒班Daytime shift 白班Nighttime shift夜班Shift leader 值班长Off duty歇班DST-Daylight saving time夏时制Mechanical completion 机械完工Interim completion 中间完工Substantial completion 大致完工Final acceptancecertificate 最终验收证书Punchlist/outstanding/Punch-off/closing 尾项/收尾System handover 系统交工Beneficial occupancy 提前占用Handover documentation 交工资料Dossier/archives 档案As-built drawing withmarks-up 竣工图Prefabrication 预制Installation/erection 安装Mechanical completion 机械完工System handover 系统交工Final acceptance 最终验收Checklist 检查清单Release 放行Precommissioning 预试车Commissioning 投料试车Commissioning guarantee 保镖Start-up 开车RFSU—Ready for Startup 作好开车装备Put into operation 投运Discipline/specialty 专业Civil 土建Structural Steel 钢结构Piping 管道Long haul piping长输管道Mechanical 机械Rotating equipment 动设备Static equipment 静设备Electrical 电气Instrumentation 仪表Lifting 吊装Heavy lifting 大型吊装Painting 油漆Lining 衬里Insulation 保温Utility 公用设施Tie-in 接点Fluid 流体介质/物料Plant air 装置/工厂风Instrument air 仪表风Compressed air 压缩空气ASU-Air Separation Unit空分装置Inert gas惰性气体Argon 氩气Oxygen 氧气Hydrogen氢气Nitrogen 氮气Natural gas 天然气LNG 液化天然气Petroleum gas 石油气LPG 液化石油气LIN 液氮LOX液氧LAR液氩PSA 变压吸附装置Cooling water冷却水make-up water补充水Potable/drinkable water饮用水fresh water 新鲜水Demineralized/softenwater 脱盐/软化水Fire water消防水Steam 蒸气Fuel 燃料Power 电、动力Power supply 供电Grid 电网Overhead cable 架空电缆Generator 发电机IGCC-integratedgasification combinedcycle/ cogeneration ofsteam and power 汽电联产Blowdown排污Lube oil润滑油Vent 排气Drain 排水/液Petrochemical 石油化工A/V distillation unit 常压/减压蒸馏装置Hydrotreater 加氢精制装置Hydrocracker 加氢裂化装置Cracker 裂解装置LOP乙烯裂解装置/低烯烃装置Delay Coker 延迟焦化装置Desulphurization unit 脱硫装置Sulphur recovery unit 硫磺回收装置Sour water stripping unit酸水汽提装置PX/Aromatics plant芳烃装置Ethylene 乙烯装置EO/EG环氧乙烷/乙二醇PE/PP/PS聚乙烯/聚丙烯/聚苯乙烯Polyester聚酯Crude oil 原油Naphtha 石脑油Gasoline 汽油Diesel 柴油Kerosene 煤油Jet kerosene 航空煤油Residue 渣油Slop 污油Terminal 接收站Jetty 码头Tank farm罐区Storage tank 储罐Loading arm 鹤臂Berth 泊位Mooring 停泊处Dolphin 系船桩PPE-Personal ProtectiveEquipment劳保用品/设备Hard hat 安全帽Safety glasses/goggles 安全眼镜/护目镜Safety boots 安全鞋Hearing protection 听力保护Safety belt/harness 安全带/安全肩带Potential hazard 隐患Hazard identification 危害识别Risk assessment 风险评估Mitigation 降低Elimination 消除HAZOP 危害与可操作性分析Tripping hazard 绊倒危害Falling hazard 坠落危害Safetyinduction/education/training 入场教育/培训Toolbox meeting 工前安全会Briefing 交底Lost-time accident 损失工时事故Reportable accident可上报事故Nearmiss 未遂事件Accident investigation 事故原因调查Major accident 重大事故Death/injury/casualty/fata lity 死亡/伤害/伤亡/死亡Act of God 天灾Disciplinary action 处罚Emergency response 应急响应Evacuation 疏散Muster point 集合点Permit to work 作业许可证Confined space entry 受限空间进入Work at heights 高空作业Scaffolding 架设Lifeline 救生绳/索Free-issued material 甲供材料Material requisition请购单Purchase specification 采购说明书Place an order定购Transportation/transfer/s hipment运输Handling倒运/搬运Transfer tank farm 中转油库Tank truck 槽车Railway car铁路货车/车皮Vessel/carrier 运输船Loading装车/装船Unloading 卸车/卸船Packing list 装箱单Bill of Lading 提单Delivery 到货Receiving inspection 到货验收Unpacking inspection开箱检查Commodity inspection 商检Ex-factory inspection 出厂检查Appearance inspection 外观检查PMT-Positive MaterialIdentification材料合金鉴定Mechanical properties 机械性能Chemical composition 化学组分Content 含量/内容Tolerance /Allowabledeviation 公差/允许偏差Geometric dimensions 几何尺寸Nonconformity 不一致品/处Reject 拒收、不合格品Acceptable 合格Unacceptable 不合格Hold 待定Use as it 回用Shortage 短缺Overage 溢出Damage/loss 损害/损失Inventory 存货Warehouse-in 入库Warehouse-out 出库Heat No.炉号Lot No. 批次Warehouse keeper 保管员Storage 存储Desiccants干燥剂Preservatives 防腐剂Corrosion inhibitor 缓蚀剂Maintenance 维护Laydown 堆放场Prefabrication yard/shop预制场/厂Withdrawal领料Issue 发放Return 退库Identification marks 标识Cutting切割Transfer 移植Traceability 可追踪性Surplus 剩余材料Bulk material大宗材料Ignition source点火源Inflammable material可燃材料Combustible material易燃材料Hazardous chemical 有害化学品Flash point 闪点Open flames 明火Flame/spark arrester 阻火塞Civil works 土建工程Site preparation 现场处理Leveling 平整Earthwork土方工程Excavation 开挖Trench/pit/sump 沟/井Spoil废土Backfill 回填Compaction 夯实Slope 边坡Slope protection 护坡Shoring 支护Dewatering 排水Water Supply and Drainagesystem供排水系统underground services 地下公用设施Concrete 混凝土Coarse/fine aggregate 粗/细骨料Portland cement 普通硅酸盐水泥Sand 沙子Flash ash 粉煤灰Admixture 混合物Mix ratio 配合比Ready mix 商品混凝土Batch plant 搅拌站Agitator 搅拌机Vibrator 振捣机Reinforced concrete 钢筋混凝土Rebar 钢筋Construction joint 施工缝Expansion joint 膨胀缝/节Water stop 止水带Vapor barrier/ Damp proof course 防潮层Pouring/Casting 浇注Curing 养护Finishing抹面Setting 硬化Slump 塌落度Compressive strength 抗压强度Crushing strength 耐压强度Tensile strength 拉伸强度Formwork 模板Stripping脱膜Embedded items 预埋件Wire mesh 钢丝网Foundation/Footing 基础Anchor bolt 地脚螺栓High strength bolt 高强螺栓Nut 螺母Stud 双头螺柱Tighten 紧固Torque wrench 转矩扳手Pile 桩Pile cap 桩帽/承台Prestressed pile 预应力桩Bored pile 钻孔桩Precast pile 预制桩Cast-in-situ pile 现场浇注桩Pile driver 打桩机Pile tip桩头Carrying/bearing capability 承载能力Settlement 沉降Reinforcing cage 钢筋笼Base plate 底板Gravel fill 砾石垫层Floor slab 底板Saddle 鞍座Grout 灌浆Mortar 砂浆Non-shrink motar不收缩砂浆Shim 垫铁Wedge 斜垫铁Flat strap 扁平钢Tack weld 点焊Waterproof layer 防水层Road 道路Pavement 铺面Vertical arrangement 竖向Bed course 基层Subgrade 路基Curb 路缘石Hard/clay shoulder 硬/软路肩Side ditch 边沟Catch basin 雨水口Side slope 边坡Greening 绿化Sidewalk 人行道Motor vehicle lane 机动车道Non-motor vehicle lane 非机动车道Speed limit 限速Crushed stone 碎石Gravel 砾石Parking lot 停车场Building 建筑Control room 中控室MCC-Motor Control Center马达控制中心Substation 变电站Standby diesel generator备用柴油发电机Transformer 变压器Compressor house压缩机房Pump station 泵站FAR-Field Auxiliary Room现场辅助间Warehouse 库房Administrative building 行政楼Laboratory 实验室Fire station 消防站Guard room 门卫室Roof 顶Wall 墙、壁板Floor 地板Apron 散水Plaster 抹灰Mastic 玛蹄脂、胶泥Door 门Window窗Parapet wall 女儿墙Skylight 天窗Downspout 雨水管Floor drain地漏Emission 排放Environmental pollution 环境污染Foreign matters 异物Contaminated water 污染水Industrial wastewater 工业废水Sanitary sewage 生活污水HVAC 暖通空调Waste water treatmentplant污水处理站Oily sewer 含油污水Clean sewer 清洁污水Rainwater/Stormwatersewer 雨水排污Septic tank化粪池Fire hydrant 消防栓Fire water monitor 消防水炮Fire alarm 火警Warning sign 警示标牌Barricade/barrier 隔离Danger, Keep out 危险，请勿入内No smoking 禁止吸烟Mind your step 注意脚下No admittance /No entry禁止入内Authorized personnel only/staff only 无关人员，不得入内Keep off the grass/lawn 请勿践踏草坪Fire extinguisher 灭火器Structural steel 钢结构Carbon steel 碳钢Stainless steel 不锈钢Killed steel 镇静钢Alloy steel 合金钢H-beam H型钢Shape/profile 型钢Angle 角钢Channel 槽钢I-beam 工字钢Hot-rolled 热轧Cold formed冷成形Beam 梁Column柱Purlin檩Truss 桁架Gusset plate 角接板Member元件Stiffener 筋板Bracket托架Girt圈梁Girder 梁Vent stack 烟囱Stack shaft 烟囱筒体Flue duct 烟道Air duct 风道Lightning arrester避雷针Platform 平台Stair梯子/斜梯Ladder直/爬梯Grating格子板Checked plate花纹板Handrail扶栏Toeboard踢脚板Deformation 变形Deflection 挠度Stability稳定性Buckling 弯曲Levelness水平度Straightness 平直性Out-of-roundness 椭圆度Coaxiality 同轴度Cleanliness清洁度Piping 管道Pipeline 管线Underground piping 地下管线Aboveground piping 地上管线Piperack 管廊、管架Pipe sleeper/track管墩Main/Header 主管/总管Manifold 集合管Branch 支管Riser 上升管Downcomer 下降管Upstream上游Downstream 下游Spool 管段Bundle 管束Hose 软管Bend 弯管Coil盘管Cap 管帽Plug 丝堵Tracer 伴热管Safety Shower 安全淋浴Eyewash Station 洗眼点Elbow 弯头Tee 三通Cross 四通Return 回弯头Reducer 大小头Nipple 短节Union 活接头Coupling 管接头Gasket 垫片Spiral wound gasket 缠绕式垫片Washer 垫圈Flange 法兰Blind 盲板Roughness 粗糙度Thread 螺纹NPT 美国国家锥形管螺纹Bolt 螺栓Nut 螺母Stud 双头螺栓Valve 阀门Check valve止回阀Globe valve 截止阀Gate valve 闸阀Ball valve 球阀Foot valve 底阀/根部阀Plug valve 柱塞阀Butterfly valve 蝶阀Control valve 调节/控制阀Safety valve 安全阀Pressure Relief Valve 卸压阀Trap 疏水器Strainer 粗滤器Silencer 消音器Sight Glass 视镜Rupture Disc 爆破片Packing 填料Butt-Welded 对接焊Socket-Welded 承插焊Flanged 法兰连接Threaded 螺纹连接Expansion Joint 膨胀节Support 支架Hanger 吊架Spring hanger弹簧吊架Shoe 管托Hydrotesting 水压试验Pneumatic testing 气压试验Leak test 试漏Blowing off/purging 吹扫NDE/NDT-NondestructiveExamination/Test 无损探伤RT-Radiographic Test 射线探伤PT-Dye Penetrant Test 着色渗透探伤UT-Ultrasonic Test 超声波探伤MT-Magnetic Powder Test 磁粉探伤Visual Examination外观检查Defect 缺陷Welding 焊接WPS- Welding Procedure Specification 焊接工艺说明书PQR- Procedure Qualification Record焊接工艺评定记录WPQ-Welder’s Performance Qualification 焊工技能评定Weld map 焊缝布置图Welder’s stamp 焊工钢印Interval 间距/间隔Base metal 母材Weld metal 焊缝金属Weldingmaterial/consumable 焊材Welding rod/electrode 焊条Flux焊剂Welding Wire 焊丝Drying oven （焊条）烘干箱Holding oven （焊条）恒温箱Quiver （焊条）保温筒Cylinder 气瓶Torch 焊炬Weldability 可焊性End preparation 开坡口Groove 坡口Heat-affected zone 热影响区Root pass打底焊Cover pass 盖面焊Fillet joint填角接头Butt joint 对接接头Socket joint承插接头Lap joint搭接接头Longitudinal seam 纵缝Circumferential seam 环缝transverse seam 横缝Flat 平焊Horizontal 横焊Vertical 立焊Overhead 仰焊Surfacing 堆焊Stringer bead直线焊道Weave bead摆动焊道Preheat 预热PWHT-Post Weld HeatTreatment 焊后热处理Temper 回火Anneal 退火Normalize 正火Interpass temperature 程/层间温度Root opening 根部间隙Welding parameter 焊接参数Weldment / Workpiece 焊件Traveling speed 送丝/移动速度Weld reinforcement 焊缝余高Deformation变形Crack 裂纹Undercut 咬边Slag inclusion夹渣Overlap 焊瘤Lack of fusion/penetration未熔透/未焊透Porosity 气孔Mismatch错位Fish eye白点/鱼眼Backgouging 清根Grinder砂轮机GMAW-Gas Metal ArcWelding 气体保护电弧焊GTAW-Gas Tungsten ArcWelding 钨极惰性气体保护焊SAW-Submerged ArcWelding 埋弧焊TIG-Tungsten Inert GasWelding氩弧焊SMAW-Shielded Metal ArcWelding 手工电弧焊Uphill 向上Downhill 向下Striking 引弧Sampling取样Testpiece/coupon/specimen 试件/试样Random/spot test 抽检Hold point 停止点Witness point 见证点Review point 审核点Check/inspection/examination 检查Supervision/monitoring 监督/监控Equipment 设备Rotating equipment 动设备Static equipment 静设备Horizontal/Vertical Vessel卧式/立式容器Tag No. /Item No. 位号Nameplate铭牌Code stamp 规范钢印Self-tapping screw 自攻螺丝Place of origin 原产地Alignment找正、对中Turbine 汽轮机Refrigerator 制冷机Expander 膨胀机Cooling Tower 冷却/循环水塔Filter 过滤器Heat Exchanger 换热器KO drum 气液分离器Boiler 锅炉Waste heat boiler余热锅炉Column/Tower 塔Tray 塔盘Internal 内件Reactor 反应器Regenerator 再生器Reboiler 重沸器Absorber 吸收塔Stripper 汽提塔Scrubber 洗涤塔Evaporator 蒸发器Cooler 冷却器Condenser 冷凝器Storage Tank 储罐Silo/Bin 料仓Mixer 混合器Cyclone 旋风分离器Separator 分离器Dryer干燥器Demister 除雾器Furnace 炉子Heater 加热炉Flare 火炬Pump 机泵Compressor 压缩机Air compressor 空压机Centrifugal 离心式Reciprocating 往复式Blower 鼓风机Fan风机Induced draft fan 引风机Conveyor 输送机Elevator 提升机Coupling 联轴节Shaft alignment 轴对中Oil flushing 油洗Manhole 人孔/检查井Package unit/equipment 快装/撬块设备Skid 撬块Long-lead equipment 长周期设备Machine train 机组E/I-Electrical/Instrument 电仪DC-Direct Current直流AC-Alternating Current 交流Induction Motor 感应电动机Oil immersed transformer油浸式变压器Rectifier 整流器Battery 电池UPS-Uninterrupted PowerSupply 不间断电源Switchgear开关柜Circuit breaker 断路器Fuse熔断器Pushbutton 按钮Relay 继电器Explosion-proof防爆Power plant 电厂Gland格兰Electrostatic precipitator静电除尘器Cabling/Wiring 布线/接线Cable laying 电缆敷设Cable tray 电缆槽架/桥架Armored cable 铠装电缆Sheath保护套Optic fiber cable光缆Coaxial cable 同轴电缆Lighting照明Lighting fixture灯具illumination levels 照度Flood light 泛光灯Energizing 送电Lighting tower and pole 照明塔架、灯杆Terminal 端子Conduit 导线管Distribution box 配电箱Socket outlet/plug 插座/插头Junction box 接线箱Grounding/earthing 接地Dielectric tests 绝缘试验SCADA-Supervision Controland Data Acquiring监测控制与数据采集Telecommunication 电信Cable TV有线电视Local/field instrument 现场仪表Cabinet 柜Panel mounted instrument盘装仪表Safety barrier 安全栅Annunciator报警器Smoke detector 感烟探测器Isolator 隔离器DCS-Distributed ControlSystem分散控制系统Siemens 西门子公司Honeywell 霍尼维尔公司Yokogawa 横河公司FCS-Fieldbus ControlSystem现场总线控制系统Busbar 母线排PMR-Plant ResourceManagement System工厂资源管理系统PLC-Programmable LogicController 可编程控制器Local/Field instrument 就地仪表Console 操作台Local control station 就地操作站ESD-Emergency Shut-down紧急停车Transmitter变送器Level gage液位计Pressure gage压力计Bimetallic thermometer双金属温度计Thermocouple热电偶Thermowell热电偶套管Flow meter流量计Restrict orifice 限流孔板Analyzer 分析仪Control valve 调节阀Solenoid valve 电磁阀Positioner 定位器Limit switch限位开关Calibration 校验/调试Loop test 回路试验Test run 试运Solo test run 单机试运Anticorrosion 防腐Cathodic protection 阴极保护Painting 油漆Enamel磁漆Epoxy resin 环氧树脂Zinc rich 富锌Red lead primer红丹底漆Polyurethane 聚氨酯Surface preparation 表面处理/除锈Sandblasting/shot blasting 喷砂/喷丸Pickling 酸洗Grinding 打磨Wire brush钢丝刷Primer 底漆Intermediate coat/tie coat 中间漆Finish/top coat 面漆Touchup 补漆Holiday test 油漆试漏Brushing 刷涂Spraying 喷涂Application 涂装Color coding色标DFT-Dry Film Thickness 干膜厚度Magnetic thickness gage 磁性测厚仪Fireproofing 防火Hot insulation 保温Cold insulation 保冷Jacket 外保护层Cladding 覆层Glass fabric/fiber glass 玻璃布Pipe shell管壳Perlite 珍珠岩Mineral wool岩棉In-situ foaming 现场发泡Spacer 支撑环Band 箍带Lap sealer 搭接密封Clip保温卡Staggered joint 错开接缝Heat loss 热损失Ingress of water 水侵入Capillary action 毛细作用Thermal conductivity 导热性Expansion/contraction 膨胀/收缩Cryogenic 低温Cellular glass 泡沫玻璃Acoustic insulation 隔音Removal 拆除/驱逐出场Disposal of处理Personal protection人员防护Access walkway通道Working area工作区Construction equipment施工机具Hand tool手动工具Power tool电动工具Precision 精度Break down 损坏Failure故障Trouble shooting 排除故障Hacksaw钢锯File锉刀Scraper刮刀Chisel凿子Socket wrench套筒扳手Hook spanner钩扳手Adjustable wrench活动扳手Pipe wrench管钳Ratchet wrench棘轮扳手Open end wrench开口扳手Screw driver螺丝刀Hand vice手钳Pliers扁嘴钳Pocket knife小刀Square rule角尺Slide gauge游标卡尺Inside and outsidemicrometer内径和外径千分尺Steel tape钢卷尺Feeler塞尺Dial gauge千分表Depth micrometer深度千分尺Wire gage线规Radius gage半径规Thread pitch gage螺距规Tachometer转速表Universal meter 万用表Spirit level水平仪Transit theodolite 经纬仪Drill钻机Hydraulic press 液压机Pipe bender 弯管机Shear 剪板机Rolling machine 滚圆机Bulldozer 推土机Loader 装载机Roller 压路机Excavator 挖掘机Pile driver 打桩机Rammer 夯实机Tipcart 翻斗车Forklift 叉车Concrete truck mixer 混凝土搅拌运输车Steel bar cutter 钢筋切割机Steel bar straighteningmachine 钢筋调直机Steel bar bender 钢筋弯曲机Crane 吊车Hoist / Chain block 倒链Winch 卷扬机Sling 吊索Jack 千斤顶Load 荷载/重物Operating radius 操作半径Site access 现场道路Crane sitting 吊车站位Out-of-level 不平度Wind force 风力Counterweight 配重Luffing 变幅Setting up 安装Dismantling 拆卸Component 部件Jib 吊臂Boom 吊杆Gin pole 抱杆/把杆Mast 桅杆Hook 吊钩Driving mechanism 行车机构Outrigger 外伸支腿/挂架Turntable转台Chassis 底盘Guy wire 拖拉绳Tag line 牵引绳Topping lift 背绳Load line 起重绳Fall line 走绳/跑绳Tailing crane 遛尾吊车Safe load indicator 安全荷载指示器Limit switch 限位开关Safety device 安全装置Abnormal noise 异常噪声Crane operator 吊车司机Signaler, banksman, flagman 指挥人员Whistle 哨子High visibility vest 反光背心Telecommunication system 通讯系统Walkie-talkie/radio 步话机/对讲机Weather conditions 天气状况Weatherproof measures 防风雨措施Suspended load/weight 悬空重物Lightning protection 避雷Multiple crane lifting 多台吊车吊庄作业Crawler crane 履带吊Truck/mobile crane 汽车吊Overhead traveling crane 天车Trolley beam 天车梁Head room净空Clearance/Distance/Interv al间距Unit 单位Night operations 晚间作业Housekeeping 文明施工Rags 抹布Trash 垃圾Oil spill 溢油Scrap /Debris 废料Code of conduct 行为准则Business ethics 商业道德Conformity/Compliance 一致性Incentive and penalty 奖惩Corrective action 纠偏措施Preventive action 预防措施Precaution 注意事项Follow-up跟进Audit 审查/审计Fire prevention and fighting 防火、消防Security 保安一、问候和介绍（36句）GREETINGS ANDINTRODUCTIONS1 How do you do?你好吗？（初次见面）2 How are you?你好吗？（日常见面）3 Fine, thanks.很好，谢谢。

EN817

3
prEN 817:2004 (E)
Introduction
In respect of potential adverse effects on the quality of water intended for human consumption, caused by the product covered by this standard: This standard provides no information as to whether the product may be used without restriction in any of the Member States of the EU or EFTA It should be noted that, while awaiting the adoption of verifiable European criteria, existing national regulations concerning the use and/or the characteristics of these products remain in force. The tests described are type tests (laboratory tests) and not quality control tests carried out during manufacture.
Robinetterie sanitaire - Mitigeurs mécaniques (PN 10) Spécifications techniques générales Sanitärarmaturen - Mechanisch einstellbare Mischer (PN 10) - Allgemeine technische Spezifikation

A constitutive model for unsaturated soils thermomechanical and computational aspects

D. Sheng (&), S. W. Sloan School of Engineering,
tions. The model by Alonso et al. (1999) is able to predict the irreversible expansion caused by wetting at low stres-
reversed plastic increment of saturation. The incremental process in the BBM and its variants. Irreversible changes
constitutive equations are also reformulated for imple- in volume and in degree of saturation upon wetting, or
stress-strain relations is derived. The constitutive model is the suction axis. With this load-collapse yield surface they
then cast into the theories and veriﬁed are able to reproduce some basic features of unsaturated
into the Barcelona Basic Model opens a full range of
(1992) proposed conceptual modiﬁcations to the BBM. By
possibilities in modelling unsaturated soil behaviour.

The Bardeen Model as a Nonlinear Magnetic Monopole

a r X i v :g r -q c /0009077v 1 22 S e p 2000The Bardeen Model as a Nonlinear Magnetic MonopoleEloy Ay´o n–Beato and Alberto Garc´ıaDepartamento de F´ısica,Centro de Investigaci´o n y de Estudios Avanzados del IPNApdo.Postal 14-740,07000M´e xico DF,MEXICOThe Bardeen model—the ﬁrst regular black hole model in General Relativity—is reinterpretedas the gravitational ﬁeld of a nonlinear magnetic monopole,i.e.,as a magnetic solution to Einsteinequations coupled to a nonlinear electrodynamics.04.20.Dw,04.20.Jb,04.70.BwThe study on the global regularity of black hole solutions is quite important in order to understand the ﬁnal state of gravitational collapse of initially regular conﬁgurations.The Penrose (weak)cosmic censorship conjecture claims that the singularities predicted by the celebrated “singularity theorems”[1,2]must be dressed by event horizons (cf.[3,4]for recent reviews).The ﬁrst black hole solutions known in General Relativity were all in accordance with such point of view.However,the conjecture does not forbid the existence of regular (singularity–free)black holes.In fact,as it was pointed by Hawking and Ellis [1],and more recently by Borde [5,6],the model proposed by Bardeen [7]at the early stage of investigations on singularities,explicitly shows the impossibility of proving more general singularity theorems,if one avoids the assumption of either the strong energy condition or the existence of global hyperbolicity.The Bardeen model [7]is a regular black hole space–time satisfying the weak energy condition.This model has been recently revived by Borde [5,6],who also clariﬁed the avoidance of singularities in this space–time,and in similar examples,as due to a topology change in the evolution of the space–like slices from open to closed [6].Other regular black hole models were proposed later [5,8–10].None of these “Bardeen black holes,”as they have been called by Borde [6],is an exact solution to Einstein equations,thus,there is no known physical sources associated with any of them.Regular black hole solutions to Einstein equations with physically reasonable sources has been reported only recently [11–14].The objective of this contribution is to provide the pioneering Bardeen model [7]with a physical interpretation.The Bardeen model is described by the metric g =− 1−2mr 2(r 2+g 2)3/2 −1dr 2+r 2d Ω2.(1)It can be noted that this metric asymptotically behaves as −g tt =1−2m/r +3mg 2/r 3+O (1/r 5);from the 1/r term it follows that the parameter m is associated with the mass of the conﬁguration (incidentally,this fact can also be veriﬁed from the explicit evaluation of the ADM mass deﬁnition),but,the following term goes as 1/r 3,therefore this does not allow one to associate the parameter g with some kind of “Coulomb”charge as,for instance,in the Reissner–Nordstr¨o m solution.This fact causes that up–to–date there is no known physical interpretation for the regularizing parameter g .The main objective of this work is to show that g is the monopole charge of a self–gravitating magnetic ﬁeld described by a nonlinear electrodynamics.The Bardeen model (1)describes a regular space–time;this can be realized from the analytical expressions of itscurvature invariantsR =6mg 2 4g 2−r 2(r 2+g 2)7,(3)R µναβR µναβ=12m 2 8g 8−4g 6r 2+47g 4r 4−12g 2r 6+4r 8sx2√As it can be noted from the derivative of the last function,it has a single minimum at x m=27.At x m,for s<s c the quoted minimum of A(x,s)is negative,for s=s c the minimum vanishes and for s>s c the minimum is positive. From the regularity of the curvature invariants(2–4),it follows that for s≤s c the singularities appearing in(1),due to the vanishing of A,are only coordinate–singularities describing the existence of event horizons.Consequently,we are in the presence of black hole space–times for g2≤4s2c m2=(16/27)m2.For the strict inequality g2<(16/27)m2, there are inner and event horizons for the Killingﬁeld k=∂/∂t,deﬁned by kµkµ=g tt=0.For the equality g2=(16/27)m2,the horizons shrink into a single one,where also∇ν(kµkµ)=0,i.e.,this case corresponds to an extreme black hole as in the Reissner–Nordstr¨o m solution.The extension of the Bardeen metric beyond the horizons, up to r=0,becomes apparent by passing to the standard advanced and retarded Eddington–Finkelstein coordinates, in terms of which the metric is well–behaved everywhere,even in the extreme case.The maximal extension of the Bardeen metric can be achieved by following the main lines used for the Reissner–Nordstr¨o m solution,taking care of course,of the more involved integration in the present case of the tortoise coordinate r∗≡ A−1dr.The global structure of the Bardeen space–time is similar to the structure of the Reissner–Nordstr¨o m black hole,as it has been pointed out by previous authors[1,6],except that the usual singularity of the Reissner–Nordstr¨o m solution,at r=0, is smoothed out and now it simply corresponds to the origin of the spherical coordinates.This fact implies that the topology of the slices change from S2×I R outside the black hole to S3inside of it,as it has been pointed by Borde [6].In what follows we will show that it is possible to provide a physical interpretation to the quoted parameter g, and to think of the Bardeen model as a regular black hole solution of General Relativity simply by coupling to the Einstein equations an appropriate nonlinear electrodynamics.In this context g is the monopole charge of a magnetic ﬁeld ruled by the quoted nonlinear electrodynamics.The dynamics of the proposed theory is governed by the actionS= dv 14πL(F) ,(6) where R is scalar curvature,and L is a function of F≡11+2sg21−2M(r)r dt2+0=dF=f′(r)sin(θ)dr∧dθ∧dϕ,(13) we conclude that f(r)=const.=g,where the integration constant has been chosen as g.As it was anticipated above, g is the magnetic monopole charge of the conﬁguration:14π π0 2π0sin(θ)dθdϕ=g,(14)where S∞is a sphere at inﬁnity.The t t component of Einstein equations(7)yieldsM′(r)=r2L(F).(15) Substituting L from(9)with F=g2/2r4,and using that m=lim r→∞M(r),one can write the integral of(15)asM(r)=m−3mg2 ∞r dy y2(r2+g2)3/2.(17)Substituting M(r)into(10)oneﬁnally obtains the Bardeen metric(1).It can be noted that the proposed source(9)satisﬁes the weak energy condition.Let X be a time–likeﬁeld,without loss of generality it can be chosen normal(XµXµ=−1).Using the right hand side of(7),one can write the local energy density along X as4πTµνXµXν=L+EλEλL F,(18) where Eλ≡FλµXµis by deﬁnition orthogonal to X,so it is an space–like vector(EλEλ>0).It follows from(18) that if L≥0and L F≥0the local energy density along any time–likeﬁeld is non–negative everywhere,which is the requirement of the weak energy condition.For the proposed non–linear electrodynamics the non–negativeness of these quantities follows from the deﬁnition(9),hence,the matter proposed by us as source of the Bardeen model satisﬁes the weak energy condition.Summarizing,for the Bardeen metric(1)we found aﬁeld source related to a nonlinear electrodynamics given by the Lagrangian(9).The solution to the Einstein equations coupled with the energy–momentum tensor associated to the magnetic strength(12)corresponds to a self–gravitating magnetic monopole charge g(14).It is well known the Bardeen model,now climbed to the status of an exact solution of Einstein equations,fulﬁlls the weak energy condition and is regular everywhere,although the invariant of the associated electromagneticﬁeld exhibits the usual singular behavior F=g2/2r4of magnetic monopoles.Finally,we would like to point out that the nonlinear electrodynamics used is stronger than the Maxwell one,in the weakﬁeld limit,as it can be seen from the expansion of the Lagrangian (9);L(F≪1)∼F F1/4,while for Maxwell electrodynamics L M(F)=F.ACKNOWLEDGMENTSThis work was partially supported by the CONACyT Grant32138E and the Sistema Nacional de Investigadores (SNI).EAB also thanks all the encouragement and guide provided by his recently late father:Erasmo Ay´o n Alayo.[5]Borde,A.,Phys.Rev.,D50,3392(1994).[6]Borde,A.,Phys.Rev.,D55,7615(1997).[7]Bardeen,J.,presented at GR5,Tiﬂis,U.S.S.R.,and published in the conference proceedings in the U.S.S.R.(1968).[8]Barrab`e s,C.,Frolov,V.P.,Phys.Rev.,D53,3215(1996).[9]Mars,M.,Mart´ın–Prats,M.M.,Senovilla,J.M.M.,Class.Quant.Grav.,13,L51(1996).[10]Cabo,A.,Ay´o n–Beato,E.,Int.J.Mod.Phys.,A14,2013(1999).[11]Ay´o n–Beato,E.,Garc´ıa,A.,Phys.Rev.Lett.,80,5056(1998).[12]Ay´o n–Beato,E.,Garc´ıa,A.,Gen.Rel.Gravit.,31,629(1999).[13]Ay´o n–Beato,E.,Garc´ıa,A.,Phys.Lett.,B464,25(1999).[14]Magli,G.,Rept.Math.Phys.,44,407(1999).4。

外研版高中英语必修三教案：Module6 Old and New

Module 6 Old and New教学设计说明话题介绍本模块主题是“Old and New”，介绍了中国人民在文明进步方面做出的历史成就和现实成就，如长城、香港国际机场和三峡大坝。

Period 1 Reading INTRODUCTION Vocabulary and speaking 和READING ANDVOCABULARY合并为第一课时“阅读课。

”课文“The Three Gorges Dam”是说明文，介绍了举世瞩目的三峡大坝。

三峡大坝设计全长2309米、坝顶海拔高程185米、混凝土浇筑总量1610万立方米，是世界上规模最大的钢筋混凝土大坝。

整个三峡工程分为前期施工期、围堰挡水期、初期运行期和后期运行期四个阶段。

Period 2 Grammar 课本54和56页合并为第二课时“语法课”，学习Non-defining clauses andcontraction of relative。

Period 3 Writing 课本55页是写作课“Writing”，阅读一则email，写作一则email。

Period 4 Speaking 课本55页“Speaking”为“口语课”，学习Talking about dams。

Period 5 Function 课本58页是“功能课”，学习使用strong adjectives，即“强势形容词”，或“书面形容词”。

Period 6 CULTURAL CORNER 课本59页的CULTURE CORNER 是“文化阅读课”，“The Empire State Building, New York”，即纽约帝国大厦。

纽约帝国大厦设计者为美国史莱夫-兰布-哈蒙建筑事务所，1931年落成，是70年代以前世界上最高的建筑。

纽约州别名帝国州，故名。

Period 7 TASK 课本60页的TASK 是“任务课”，学习用英文preparing a news bulletin。

土石坝逐渐溃坝水流模拟

I
华中科技大学硕士学位论文
Abstract
The problem of dam failures has always been of great important because of their disastrous effects. The numerical simulation of dam failure flow can divide into sudden catastrophic failure and gradual failure. The current study is focused on sudden catastrophic failure. However, as the most common type of dam, earthen embankment has the largest number of failure, and the failure of earthen embankment is mainly gradual. For this reason, the present paper applies general CFD software FLUENT and tries to simulate the dam break flow of gradual failure. The dissertation starts with an introduction of this study discipline, including dam break flow simulation and mechanism of earthen embankment failure. Based on this, different from current two dimensional flow simulation, three dimensional CFD software FLUENT is introduced in this paper to simulate the dam break flow. Validated by some popular experiments and hypothetic tests, FLUENT is suitable for the study of dam break flow. Model of OSMAN slope stability analysis is employed to simulate the breach development. Based on physics, this model is more reasonable than others, which considers water flow, material character of dam, slope stability and so on. Dynamic mesh and user defined functions of FLUENT are used to program UDF of gradual enlarged breach. After calculation in FLUENT, the process of enlarged breach which is influenced by water flow and the flow state which is influenced by breach can be shown. And the breach hydrograph can also be acquired by program corresponding UDF. Key words: dam break gradual failure FLUENT water flow state

Multifunctional Materials Used in Automotive Industry

Multifunctional Materials Used in Automotive Industry:A Critical ReviewKonstantinos Salonitis,John Pandremenos,John Paralikas,and George ChryssolourisAbstract Nowadays,advanced materials and related processes in the automotive industry,are more widely used,leading to an effort towards reducing weight and fuel consumption.The use of such advanced materials and technologies tends to increase the cost.Multifunctional materials(MFMs)and related processing technologies aim at overcoming this increase of cost by exploiting the high level of functional inte-gration.MFMs are designed so as to meet speciﬁc requirements through tailored properties.The use of such materials,in the automotive body construction,can help reduce produced parts,lightweight design,high level of integration of functionali-ties,advancements in mechanical properties of structures etc.In the current study, there is a clear deﬁnition of MFMs,and a critical view of such materials used both in the automotive body construction and in other industrial applications. Keywords Multifunctional·Materials·Functions·Automotive body1IntroductionThe increasing competition in global market has pushed manufacturers to develop new concepts and forms of their products.The development of the materials used, plays a major role in the formation of new concepts and manufacturing technolo-gies.The Materials created by intimately integrating different types of materials as well as functions for implementing new applications that can be proved both tech-nically challenging and economically favorable[14,24],are called multifunctional materials.This kind of materials promises to provide a new level of functionality, adaptability,and tailorability for future engineered systems[42,50].The number of K.Salonitis,J.Pandremenos,J.Paralikas,and G.Chryssolouris( )Laboratory for Manufacturing Systems and Automation,Department of Mechanical Engineering and Aeronautics,University of Patras,Patras,Greecee-mail:{kosal,jpandrem,jparali,xrisol}@lms.mech.upatras.grS.Pantelakis,C.Rodopoulos(eds.),Engineering Against Fracture:Proceedings59 of the1st Conference,c Springer Science+Business Media B.V.200960K.Salonitis et al. parts can be reduced and a lightweight design can be easily achieved.In addition to this,a higher level of functional integration can be achieved andﬁnally,the overall cost can be reduced.Recent research studies focus on structural materials incorpo-rating different functions,into their processing techniques,as well as into coatings of metallic surfaces to improve their properties and enhance them with functional-ities[17,47,59,66].Materials that are truly integrated this is the true promise of multifunctional materials for performance tailored structures[45].The entire automotive industry needs to reduce fuel consumption and therefore, the emission of their products by the methods of weight(without losses in per-formance)savings and technological improvements[13,38].Great potential weight savings can be obtained in the vehicle structure,with a body-in-white(BIW)provid-ing the largest contribution.In order to reap the beneﬁts of weight-savings in cost and fuel economy,the functional properties of a vehicle’s body-in-white(BIW), including its requirements for passive safety,service life,dynamic stiffness,acous-tics and comfort must be improved[6].MFMs could be distinguished in materials that combine properties and functions unaffected from external stimuli and the time domain,in materials that sense the process information and respond(smart materials)[18],as well as in affordable composite materials[24,52].The use of advanced materials can also affect design methods and concepts in the automotive industry.Modularity is a major trend,which is used for simplify-ing the management of complex systems[54].Modularity in design(MID),in use (MIU)and in production(MIP)are the three main categories,which provideﬂex-ibility,speed and expanded design capability and reduced cost(labor,engineering efﬁciency,scale economics and lower).These design techniques allow the use of ad-vanced materials,such as MFMs,and related processing technologies without any signiﬁcant cost increase.2Materials Used in Automotive IndustryThe functionality requirements of vehicles have increased[62],and the materials help these requirements to be met.In order for advanced materials to be used in mass-produced consumer products such as automobiles,they must exhibit a number of general characteristics[38,62],such as affordable cost and tooling,the supply of raw materials to be plentiful and readily available,and the highly reliable parts and assemblies to be recyclable.2.1Advanced Steels and Pre-coated SteelsDifferent types of steels still remain the most commonly used materials for vehi-cles.They offer a wide variety of material characteristics such as thermal,chemical or mechanical resistance,ease of manufacture and durability[76].High strengthMultifunctional Materials Used in Automotive Industry:A Critical Review61Fig.1Schematic of AHSS steels(shown in color)compared to low strength steels(dark grey) and traditional HSS(light grey)[2](HSS)and advanced high strength(AHSS)steel grades are increasingly used in high-volume production for parts such as sheets or proﬁles,which are assembled by advanced manufacturing techniques(Fig.1).Steels are initially classiﬁed as hot and cold rolled[2],which are then categorized according to their production method and quality(commercial CQ,drawing DQ,deep drawing DDQ,etc.)for formabil-ity.In a deeper view,automotive steels can also be deﬁned in a number of different ways[38,77].The most common steels used by automotive industries are(i)by met-allurgical designation,(ii)based on mechanical properties and(iii)based on total elongation.The most common and evolving steel types are:mild,bake-hardenable (BH),isotropic,carbon-manganese(CM),high strength low alloy(HSLA),dual phase(DP),transformation induced plasticity(TRIP),complex phase(CP),marten-sitic(Mart),ferritic-bainitic(FB),twinning induced plasticity(TWIP),hot formed (HF),post forming heat treatable(PFHT)and evolving AHSS steels[37].In response to the automotive industry’s demands for better functional steels,the steel industry develops new types.TRIP and TWIP steels are both categorized as AHSS.The Evolving AHSS steels are designed to reduce density,improve strength and/or increase elongation.TWIP steels have become very important for automotive applications.They have a great ability to absorb the crass energy extremely quickly [60].TRIP steel can resist high stresses without deforming.TWIP steel deforms with low stresses,but does not break until the strain reaches around90%.Salzgitter AG[60]launches on the market the evolution of TRIP steel as HSD(high strength and ductility)steel.This type of steel is extremely light due to the low density of its alloy elements.The TWIP/TRIP steels can be used in thinner sheets that result in10–30%weight savings in the automotive structures.Arcelor and ThyssenKrupp have developed a new super-high strength steel with TWIP for weight reduction and improved crash resistance named X-IP1000[15,51].This austenitic product, which is based on high manganese alloy metallurgy,has a tensile strength greater62K.Salonitis et al. than1,000MPa for a total elongation superior to50%.X-IP steels exhibit the best combination of strength and ductility over the whole range of ductile steel grades for automotive applications,such as forming of complex shapes and exploiting energy absorption in passive safety.The need of the automotive industry to improve corrosion resistance has brought about an increased use of metallic coated steel sheets in place of cold rolled (uncoated)sheets formerly used[2].The application of multifunctional coating can be classiﬁed into the traditional four-step model used for electroplating:(1) pre-treatment,(2)plating,(3)passivation and(4)seal[47].Major advantages of applying precoated steels in the automotive industry,are the enhanced corrosion re-sistance,decorativeﬁnish,controlled friction,thermal shock management,ease of operation,paintability,economic,and weldability[75].The challenges of managing increased loads and additional functionalities while keeping weight down has resulted in a signiﬁcant transformation in the use of steel and the blend of several steel grades.The designs of modern cars can be divided into four main groups:monocoque,unibody,spaceframe,mix of unibody/spaceframe [33].Steel unibody has for years been the dominant method of producing vehicle bodies in the automotive industry.BMW(3-Series)managed to improve the body’s functionality and to increase the average minimum yield strength and signiﬁcant weight saving.Blanding of steel grades has also been used by Mercedes-Benz(M-Class)[30,32].2.2Aluminum AlloysThe European automotive industry has more than doubled the average amount of aluminum used for the construction of passenger cars.Determining the right alloy for the body structure and hang-on panels has been the subject of considerable devel-opment effort and most of the activity is concentrated on a relatively small number of alloys[49].One of the main advances of aluminum is its availability in a large variety of semi-ﬁnished forms.Such semis are very suitable for mass production and innovative solutions in the form of compact and high integrated parts that meet the high demands of performance,quality and cost efﬁcient manufacturability[34]. The main aluminum alloy classes for automotive sheet application are the non heat treatable Al-Mg(EN5000series)and the heat treatable Al-Mg-Si(EN6000se-ries)alloy system.Undoubtedly,aluminum is more expensive to be manufactured than steel is[12].Aluminum alloys offer a wide range of properties that can be en-gineered precisely to the demands of speciﬁc automotive applications,through the choice of alloy,temper and fabrication process.The key characteristics of aluminum in the automotive use are lightweight,high strength to weight ratio,resilience,cor-rosion resistance,forming and fabricating,joining,crashworthiness,cold resistance, recyclability,thermal conductivity and reﬂectivity[69].Audi with the use of ASF(Audi Space Frame[7,40,56]),has improved A8han-dling and safety performance and achieved a high-strength aluminum framework,Multifunctional Materials Used in Automotive Industry:A Critical Review63 which the larger sheet aluminum elements were integrated into and performed mul-tiple load-bearing functions[6].Audi has also simpliﬁed the production line by placing body production andﬁnal assembly in one building and improved body stiffness(improved passenger comforts[7,8],provided less vibrations,as well as maximum stability with minimal mass)[7,40].Novelis Fusion TM technology[53] is a breakthrough process that simultaneously casts multiple alloy layers into a sin-gle aluminum rolling ingot.The whole process can be used as an automotive sheet with both strength and improved formability to enable new design options.2.3Aluminum FoamsThe aluminum foam is a new class of materials with low densities and novel phys-ical,mechanical,thermal,electrical and acoustic properties.It offers potential for lightweight structures,for energy absorption,and for thermal management,as it is recyclable and non toxic[5].Foamed aluminum can be produced by two methods, powder metallurgy and melt foaming.The properties(energy absorption,thermal, sound insulation and mechanical strength)depend upon the history of the foam-ing process[64].Aluminum foams can be classiﬁed according to their structure, into open-cell(can form an interconnected network)and closed-cell(The pores can be sealed)foams.The applications of the aluminum foams related to the au-tomotive industry,and their allocation to the automotive body depends on their structure.Major multifunctionalities offered by aluminum foams are strain isolation, mechanical damping,vibration control,NVH improvements,energy absorption,en-ergy and thermal management,excellent strength and stiffness to weight ratios and ﬁltering[5].Aluminum foams with open-celled structures have a wide range of applica-tions(ﬁltration,separation,heat or mass exchange,sound and energy absorption [39,70,71])in functional structures.Closed cell aluminum foam offers a unique combination of properties such as low density,high stiffness and energy absorp-tion[19].Cymat[16]has introduced and commercialized the Stabilized Aluminum Foam(SAF),a revolutionary material with numerous automotive applications[16].Another type of aluminum foam is that of the Advanced Pore Morphology (APM)[25].This type consists of small volume metallic foam elements(shaped spherical)which are expanded in bulk/mass production.Joined to each other in a separate process step the foam elements form the APM foam part.This kind of aluminum foam has pore morphology,and mechanical properties adjustable independent of the part’s geometry and volume.In addition,it has maximum vol-ume of the largest pores for complete part volume guaranteed,homogeneous,and multi-phase and/or gradient pore structure.Mono-,bi-or multi-modal combina-tions/mixtures of APM foam elements with different properties(density,geometry, matrix material)are possible[67].64K.Salonitis et al.2.4Magnesium AlloysMagnesium is a quite attractive material for automotive use,primary because of its light weight,36%lighter than aluminium and78%lighter than iron.When alloyed, Mg has the highest strength-to-weight ratio of all the structural metals.Magnesium alloys are currently used relatively in small quantities for auto parts,generally lim-ited to die castings(e.g.housings).Mg sheet can be used in body non-structural and semi-structural applications,while extrusions could be used in such structural ap-plications as spaceframes[27].The key properties and functions of magnesium,in automotive applications,are lightweight,reduction of number of parts,recyclability, excellent mechanical properties at high temperatures[20].The development of new alloys has helped acceptable properties to be achieved[27].Mg may have lower fabrication and joining costs.Its substitu-tion by lightweight materials may enable secondary weight savings,and lifetime fuel costs to be reduced,so the total life-cycle cost of a Mg part may actually be lower than that made from another material.Magnesium is quite easy to form and join.Several drawbacks(most amenable to technical or institutionalﬁxes)with the most important one the material’s physical properties and unstable price[72]have limited the growth of Mg usage in automobiles[26,48].A considerable application is the Magnesium space-frame(VW1-Liter Car)[33,65]consumed fuel just1l per 100km by using magnesium that is lightweight,has high strength to weight ratio and excellent die-casting properties.The space frame is constructed with composite welding and adhesive bonding of different magnesium alloys.2.5Sandwich MaterialsStressed skin sandwich panels are among the most efﬁcient constructions,based on stiffness per unit weight bined with natural sound dampening and ther-mal attenuation properties,sandwich panels can offer signiﬁcant improvements in reducing vehicle weight,reducing parts and streamlining the body assembly pro-cess.The greater the thickness is in the core material,the greater the increases are in the bending/ﬂexural strength and especially in stiffness[29].Functions achieved using combinations of different materials and core materials in sandwich structure are:weight saving,high strength to weight ratios,customization,noise damping, resistant to harmful chemicals and absorption of shock and impact loads[58].Tribond R ,patented from ThyssenKrupp,is a three layer hot strip produced byﬁrmly bonded layers made from different steel grades with correspondingly different properties[67].In addition to the“wear-resistant/ductile/wear-resistant”combination,other combinations of properties are also conceivable.Aluminum foams could be used as cores into multifunctional sandwiches.In particular,struc-tural efﬁciency,cost requirements,and improvements in manufacturing processes have created a growing interest in aluminum foams and in layered composite materi-als such as aluminum foam sandwiches(AFS).This foam,produced with aluminiumMultifunctional Materials Used in Automotive Industry:A Critical Review65 powder and a foaming agent,can be molded into complex3D geometry[48]. Arcelor has developed a three layer composite Usilight steel/polymer sandwich[31]. With the use of this composite,preliminary studies suggest a typical total system weight and cost reduction up to20%–while achieving noise reduction levels up to 50%[4].Metal-plastic-metal laminates,the so called MPM-sheets,have been in the market and possessed by pressing for many years.BONDAL R in Mercedes-Benz A-Class[35,74]managed to balance the vehicles’weight,to reduce manufacturing costs and insulate airborne,structural born noise and vibration.2.6Plastics,Composites and Nano-compositesPlastics have low density,are mostly economic to be produced and their characteris-tics can beﬁtted to speciﬁc demands.Their wide variety of properties can be created through chemical or physical material combinations[76].Polymeric materials are characterized by long chains of repeated molecule units known as“Polymers”[22]. These long chains intertwine to form the bulk of the plastic.Most plastics can be classiﬁed as either thermoplastic(the polymer chains are only weakly bonded)or thermoset(adjacent polymer chains form strong cross links).SMC is a type ofﬁbre reinforced plastic,which primarily consists of a ther-mosetting resin,glassﬁbre reinforcement,andﬁller.Additional ingredients,such as low-proﬁle additives cure initiations,thickeners,and mould release agents are used for enhancing the performance or processing of the material.Advantages of SMC versus steel automotive constructions are considerable weight savings,corrosion re-sistance,reduced tooling cost,resistance to minor impact,surfaceﬁnish,as well as compatibility with steel body assembly[63].Fiber reinforced composites are made ofﬁbers and a matrix.Fibers are the re-inforcement and the main source of strength,while the matrix‘glues’in shape all theﬁbers together and transfers the stresses between the reinforcingﬁbers.The pri-mary function of theﬁbers is to carry the loads along their longitudinal directions, while those of the matrix are to transfer stresses between the reinforcingﬁbers (holdﬁbers together)and protect theﬁbers from mechanical and/or environmen-tal monﬁber reinforced agents include Aluminum,Aluminum oxide, Aluminum silica,Asbestos,Beryllium,Beryllium carbide,Beryllium oxide,Carbon (Graphite),Glass(E-glass,S-glass,D-glass),Molybdenum,Polyamide(Aromatic polyamide,Aramid),e.g.Kevlar29and Kevlar49,Quartz(Fused silica),Natural ﬁbers,etc.[21,43,57].Common resin materials include Resin Matrix,epoxy,phe-nolic,polyester,polyurethane and Vinyl Ester[21].Long-Fiber reinforced Thermoplastics(LFT)have gained an increasing market share in the automotive industry in the last decade.The LFT-D process differs fundamentally from the GMT and LFT-G processes in that it avoids the need for semi-ﬁnished products manufactured by the material supplier[41].It is there-fore a cost effective measure.Further advantages of this technology are high output-capacity andﬂexibility inﬁber and polymer-modiﬁcation in accordance with the customers’needs.66K.Salonitis et al.People are turning to nanomaterials as a new tool to improve properties and gain multifunctionality[55].Multifunctional composites with application in the automo-tive sector can be classiﬁed into three main categories:(i)Nanocomposites(carbon nanotubes,nanoclays),(ii)Multi-functional composites(SMA and Piezo-materials) and(iii)Magnetic nanocomposites(metal nanoparticles).Nanocomposites are a novel class of polymeric materials exhibiting superior mechanical,thermal,and pro-cessing properties suitable for replacing metals in automotive[28].Nanocomposite plastic parts offer great advantages(weight and energy savings).Nanocomposite-based parts provide stiffness,strength,and reliability comparable with better metals. They offer corrosion resistance,noise dampening and enhanced modulus,thermal and dimensional stability[28,55].With the use of Fillers or nanoﬁllers,the heat-distortion temperature of materials increased and the material could withstand high or elevated temperatures.However,nanoﬁllers are not expected to impart many of the property losses of conventionalﬁllers.Nanoclays compounds,in automotive ap-plications,have advantages including reduced weight,a wider processing window, improved colourability,improved toughness and rheological properties and im-proved scratch and mar resistance[28].Mercedes Benz nano-based clearcoats[11] are resistant to scratch and mar,provide less stress concentration and reduce dam-age potential.In addition to this,Hummer H2cargo bed nanocomposites[10,61,68], reduce cargo’s bed weight,improve scratch protection,enhance the vehicles’over-all efﬁciency and improve rheological properties.Menzolit’s Advanced SMC for 2004SLR McLaren Mercedes[23,46]can be molded similar to standard SMC and exceeds by far the properties of standard.Great weight reduction(even lighter than the same panels made of aluminum),excellent paint surfaces,improved energy absorption during crash and mechanical properties just a little below high perfor-mance composites are some additional advantages.BMW1series multifunction tray from D-LFT[9]has improved the part performance and reduced the com-plexity in moulder’s operations offering a unique product in the market.Finally, Maserati Quattroporte uses nanotechnology in the engine bay[44]and achieves re-duced weight,increased mechanical performance(especially at high temperatures) and improved surface appearance.3Multi-material Approach in Automotive IndustrySeveral attempts have been made in the automotive industry for e exploiting the ad-vantages of each material category in the automotive body.The application of the multi-material approach offers opportunities for combination of functions,prop-erties and processing technologies into a single body structure,with signiﬁcant advantages.Lamborghini uses a hybrid solution with combination of stampings and space-frame elements in Gallardo’s body.Cast,extruded and sheet components are in-tegrated into the body as modules or individual components[36].New Steel Body (NSB R )Thyssen Krupp[1,73]offers enormous weight savings,better utilization ofMultifunctional Materials Used in Automotive Industry:A Critical Review 67Trunk lid (thermosetting material): −2 kg (−4.4 lb)Fenders (thermoplastic resin): −4 kg (−8.8 lb)Front and rear bumper beam (carbon fiber): −6.8 kg (−15 lb)Hood (aluminum and 2kbonding): −11 kg (−24 lb)Front end(aluminum): −20 kg(−44 lb)Roof (carbonfiber): −4.3 kg(−9.5 lb)Doors (aluminum): −10 kg (−22 lb)Fig.2Mixed-material approach used in the BMW M6sports car [32]packaging space,thanks to the absence of ﬂanges,enhanced torsional stiffness and crash performance,uniform stretching of the material,low tooling costs and very high part accuracy.Additionally,Arcelor’s Body Concept (ABC)[3]achieves cost reduction,improved pedestrian and passenger safety and it ﬁnally demonstrates the steel solution advantages (mass savings,improved vehicle strength and reduction in fuel consumption).BMW M6mixed-material approach [12,30,32]has reduced the vehicles’weight,offered advanced car crashworthiness and achieved optimum ve-hicle balance.BMW researchers have made use of advanced materials (steel grades,aluminium,and plastic and carbon ﬁbre)in this project (Fig.2).4ConclusionsThe major multifunctional materials used and the trends for evolving materials in the automotive industry have been presented in the current study.The term “mul-tifunctional”has been given from the industrial point of view,and major materials used in the automotive body constructions have been identiﬁed.Industrial applica-tions,and multifunctionality achieved have been described,in order for an emphasis to be given to the applicability of advanced materials in the automotive industry.The higher cost of advanced material could be overcome using advanced process-ing,“intelligent”choice and application of such materials,as well as a high level of integration of functions into the automotive structure.Several applications of the mix-material approach have been described,as this trend has become a more com-mon way of thinking for automotive manufacturers and suppliers.Acknowledgement The work reported in this paper was partially supported by CEC/FP6NMP Programme,“Integration Multi-functional materials and related production technologies integrated into the Automotive industry of the future”(FP6–2004-NMP-NI-4–026621).68K.Salonitis et al. References1.Adam,H.,Osburg,B.,Patberg,L.,Gruneklee,A.,Floth,T.,Hinz,M.,2004,NSB R NewSteel-Body–Auto body weight reduction with steel,ThyssenKrupp techforum,July2.American Iron and Steel Institute&Auto/Steel Partnership,2002,Automotive steel designmanual,Revision6.13.Arcelor Auto Newsletter,2005,The ABC project enters the limelight,No.9,January4.Arcelor–Steel Solutions for a Better World,Quiet Steel,URL:/fcse/prg/selfware.pl?id sitemap=37&language=EN,/body/ en/material.php5.Ashby,M.F.,Evans,A.G.,Fleck,N.A.,Gibson,L.J.,Hutchinson,J.W.,Wadley,H.N.,2000,Metal Foams:A Design guide,Butterworth Heinemann,Oxford,UK6.Audi of America Press Site,2003,AUDI and Weight-Saving Construction–FromPioneer in Aluminum To High-V olume Production,URL:/article display.cfm?article id=91017.Audi of America Press Site,2003,Latest-Generation AUDI Space Frame Advances De-sign,Safety and Performance Standards,URL:/article display.cfm?article id=89948.Automotive Engineering International Online:Global Viewpoints,2006,Audi A2production,URL:/automag/globalview02–00/01.htm9.Borealis,Shaping the Future with Plastics,PP for d-LFT,URL:http://www.borealisgroup.com/public/customer/automotive/dlft/MainPage.jsp#10.Birch,S.,2004,“Dwarf”in Greek,the Word Nano has Big Implications,Material Innovations,AEI Magazine,August2004,URL:11.Birch,S.,2004,Mercedes Makes a Scratch Hit,Material Innovations,AEI Magazine,February2004,URL:12.Carle,D.,Blount,G.,1999,The suitability of aluminium as an alternative material for carbodies,Materials and Design,20:267–27213.Cole,G.,Glove,A.,Jeryan,R.,Davies,G.,1997,Steel World21:75–83mittee on Materials Research for Defense After Next,2003,Materials Research to Meet21st Century Defense Needs,National Research Council15.Cugy,P.,Hildenbrand,A.,Bouzekri,M.,Cornette,D.,Goglu,S.,Hofmann,H.,2006,ASuper-High Strength FE-MN-C Austenitic Steel with Excellent Formability for Automotive Applications,URL:/phase-trans/2005/LINK/92.pdf16.Cymat(CYM)foam products,Aluminium Foam Technology Applied to Automotive Design,URL:/Cymat Foam products0.htm17.Department of Trade and Industry,2006,Report on Key Technology Area:Advanced Materi-als,URL:/ﬁles/ﬁle27985.pdf18.Department of Trade and Industry,2006,The Technology Programme:Smart Materials andRelated Structures,URL:/ﬁles/ﬁle18875.pdf19.Deqing,W.,Xiangjun,M.,Weiwei,X.,Ziyuan,S.,2006,Effect of processing parameters oncell structure of an aluminum foam,Materials Science and Engineering,A420:235–23920.Duffy,L.,1996,Magnesium alloys–An introduction,Materials World,4(3):127–13021.EFUNDA,Engineering Fundamentals,Fiber Reinforced Composites,URL:http://www./formulae/solid mechanics/composites/comp FRC intro.cfm22.EFUNDA,Engineering Fundamentals,Polymer Materials-Overview,URL:http://www./materials/polymers/science/polymer science intro.cfm23.European Alliance for SMC/BMC,News from the Member Companies,Carbon Fibre(CF)Reinforced SMC Used in Series Production,URL:http://www.smc-alliance.com/members/members news/members news.html24.Flatau,A.B.,Chong,K.P.,2002,Dynamic smart and structural systems,Engineering Struc-tures,24:261–27025.Fraunhofer IFAM,Advanced Pore Morphology(APM)Foams,URL:http://www.ifam.fhg.de/index.php?seite=/2801/leichtbauwerkstoffe/metallschaeume/apmschaum/&lang=en。

Understanding protein folding with energy landscape theory

9. Appendix : Glossary of terms 10. References 158
1. Introduction The current explosion of research in molecular biology was made possible by the profound discovery that hereditary information is stored and passed on in the simple, one-dimensional
Quarterly Reviews of Biophysics 35, 2 (2002), pp. 111–167. " 2002 Cambridge University Press DOI : 10.1017/S0033583502003761 Printed in the United Kingdom
(1D) sequence of DNA base pairs (Watson & Crick, 1953). The connection between heredity and biological function is made through the transmission of this 1D information, through RNA, to the protein sequence of amino acids. The information contained in this sequence is now known to be suﬃcient to completely determine a protein’s geometrical 3D structure, at least for simpler proteins which are observed to reliably refold when denatured in vitro, i.e. without the aid of any cellular machinery such as chaperones or steric (geometrical) constraints due to the presence of a ribosomal surface (for example Anﬁnsen, 1973) (see Fig. 1). Folding to a speciﬁc structure is typically a prerequisite for a protein to function, and structural and functional probes are both often used in the laboratory to test for the in vitro yield of folded proteins in an experiment. Further understanding of the molecular description of life thus requires answering the deceptively simple question of how the 1D sequence of amino acids in a protein chain

参考文献a

144.谈庆明.量纲分析[M]. 合肥：中国科学技术大学出版社,2005.145.谢多夫.力学中的相似方法与量纲理论[M]. 北京：科学出版社，1982.146.Bardet J P, Ichii,Lin CH. A computer program for equivalent-liner earthquake site response analyses of layered soil A: University of southern California,2000.147.Schuster,R.l. Usoi landslide dam, Southestern Tajikistan. Proceedings, International Symposiumon Landslide Mitigation and Protection of Culyural and Natural heritage, UNESCO and Kyoto University, Kyoto,Japan,21-25,January,2002.489-505.148.Dakoulas P, Gazetas G. Effective-stress analysis of gravity quay walls, Proceedings of the 1lth Int.Conf. On soil Dynamics and Earthquake Engineering and the 3th Int. Conf. On Earthquake Geotechnical Engineering,l:326-333,2004.149.T.Sato T, Matsumaru T. Liquefaction and ground flow analysis using the element free Galerkin method. Proceedings of KKCNN Symposium on Civil Engineering,2003.150.Tang X, SatoT. H-adaptivity applied to liquefiable soil in nonlinear analysis of soil-pile interaction soil Dynamics & Earthquake Engineering, 25: 689-699, 2005.151.Zhongtao Wang, Maotian Luan, Zhange Liu, DongWang. Numerieal Analysis of Dynamic Response of Seabed under Random Wave Loading. In: Gourvenec S and Cassidy M. Frontiers in Offshore Geotechnics.London:Taylor and Francis,2005,589-594.152.David M Boore, Christopher D SLephens, William B Joyner. Comments on Baseline Correction of Digital Strong-Motion Data Examples from the 1999 Hector Mine Califor-nia Earthquake[J].Bulletin of the Seismological Society of America,2002,92(4):1543-1560. 153.PARSONS T, CHEN J, KIRBY E. Stress changes from the 2008 Wenchuan earthquake and increased hazard in the Sichuan basin[J].Nature.2008,454:509~510.154.Elgamal A, Fraser M, McMartin F. On-line L, ducntional Shake Table, Experiments [J].Journal of Professional Issues in Engineering Education and Practice, 2005-131(1):41-49. 155.Chen W Y. Physical Model Studies of Seismic Slope Respouseand Performance (PhD Dissertation)[J].Berkeley,Calf.:U.C.Berkeley,2004.156.Lin M L, Wang K L. Seismic slope behavior malarge-scale shaking table model test [J].Engineering Geology, 2006,(86):118-133.157.Kramer S L, Lindwall N W. Dimensionality and di rectionality effects in Newmark sliding block analyses [J].Journal of Geotechnical and Geoenvironmental Engineering, 2004,130(3):303-315.158.Dong-Woo Ko and Han-Seon lee. Shaking table tests on a high-rise RC building model havingtorsional eccentricity in soft lower storeys. Earthquake Engineering and struetural Dynamics.2006.159.Xilin Lu, Jianbao Li, Wensheng Lu, Bin Zhao. Shaking table test of a model of HWS tall building [A].Proceedings of the CTBUH[C].Seoul.2004:359-364.160.Fast Lagrangian Analysis of Continua in 3 Dimensions[M]．Minnesom：Itasca Consulting Group，Inc,2005.161.陈育民,徐鼎平.FLAC/FLAC3D基础与工程实例[M].北京:中国水利水电出版社.2009. 162.陈育民.砂土液化后流动大变形试验与计算方法研究[D].南京:河海大学,2007.163.GB18306-2001,中国地震动参数区划图.北京:国家质量技术监督局,2001.164.GB50011-2001.建筑抗震设计规范.北京: 中华人民共和国住房和城乡建设部,2010. 165.DL5073-2000.水工建筑物抗震设计规范,北京：中华人民共和国国家经济贸易委员会, 2000.166.孙恩吉, 张兴凯, 程嵩. 尾矿库溃坝离心机振动模型试验研究[J].中国安全科学学报,2012,22(6):130-135.167.尹光志, 敬小非, 魏作安. 尾矿坝溃坝相似模拟试验研究[J].岩石力学与工程学报,2010,29(2):3830-3838.168.敬小非, 尹光志, 魏作安. 尾矿坝垮塌机制与溃决模式试验研究[J]. 岩土力学,2011,32(5):1377-1404.169.J.Hubl and H.Steinwendtner .Two-Dimensional Simulation of Two Viscous Debris Flows in Austria[J].Phys.Chem.Earth(C),V ol.26,No.9,PP.639一644,2001.170.RICO M, BENITO G, DIEZ-HERRERO A. Floods from tailings dam failures[J]，Journal of Hazardous Materials，2008，154(31)：79-87.171.Adrian Stola, Christian Huggel. Debris flows in the Swiss National Park: the influence of different flow models and varying DEM grid size on modeling results [J]. Landslides, 2008(5):311-319.172.Cetina, M. Krzyk, M. Two-dimensional mathematical modeling of debris flows with Praetical applications [J]. Water Pollution Vll: Modelling, Measuring and Prediction. 2003,9:435-444. 173.Hanson G J, Temple D M, and Cook K R. Dam Overtopping Resistance and BreachProcesses Research [A].Proceedings of the 1999 Annual Conference Association of State Dam Safety Officials[C]. St. Louis, MO, 1999.174.Wahl T L. Prediction of Embankment Dam Breach Parameters: A literature Review and Needs Assessment [R]. DSS-98-004, Dam Safety Research Report, U.S. Bureau of Reclamation, 1998.175.Brown C A, and G raham W J. Assessing the threat to life from dam failure [J],. Water Resources Bulletin, 1988, 24(6):72-77.。

考虑永磁体不可逆退磁的磁齿轮复合电机设计

乡严殳计分析eSgn and 薇特电力U2021年第49卷第1期考虑永磁体不可逆退磁的磁齿轮复合电机设计陈彬W，肖勇1，2,3,李权锋3,刘美扬3（1.空调设备及系统运行节能国家重点实验室，珠海519070；2.广东省制冷设备节能环保技术企业重点实验室，珠海519070；3.珠海格力电器股份有限公司，珠海519070)摘要:提出了一种考虑永磁体不可逆退磁的磁齿轮复合电机(MGM)的设计方法。

通过有限元方法分析了MGM永磁体的退磁情况,建立了MGM抗退磁能力的评估模型以及退磁率的计算方法，提出了一种综合考虑电机抗退磁能力、转矩密度、永磁体利用率的设计方法，制作了样机，转矩密度达到60.9N-m/L，永磁体利用率为50N-m^kg,永磁体在2倍额定电流下不会发生不可逆退磁，可以保证MGM的可靠运行。

关键词:退磁特性;磁齿轮复合电机;永磁体利用率;转矩密度中图分类号:TM359.9文献标志码:A文章编号：1004-7018(2021)01-0005-05Design of Magnetically Geared Machine Considering theIrreversible Demagnetization of the Permanent MagnetCHEN Bin1,2,3,XIAO Yong1,2,3,LI Quan-feng,LIU Mei-yang(1.State Key Laboratory of Air-Conditioning Equipment and System Energy Conservation,Zhuhai519070,China;2.Guangdong Key Laboratory of Refrigeration Equipment and Energy Conservation Technology,Zhuhai519070,China;3.Gree Electric Appliances,Inc.of Zhuhai,Zhuhai519070,China)Abstract:A design method of magnetically geared machine(MGM)was presented considering the irreversible demagnetization of the permanent magnet(PM).The demagnetization of the PMs of MGM was analyzed by the finite elementmethod( FEM),and the evaluation model of the anti-demagnetization ability of the MGM and the calculation method of thedemagnetization rate were established.A design method comprehensive considering the anti-demagnetization ability,torquedensity,and PM utilization of the machine was proposed.The prototype was made.The torque density reachesd60.9N•m/L,and the PM utilization rate was50N•m/kg.The PM could not be irreversibly demagnetized at twice the rated cur-rent.The reliable operation of MGM could be guaranteed.Key words:demagnetization characteristics,magnetically geared machine(MGM),permanent magnet utilization,陈torque density0引言20世纪50年代,磁齿轮的概念被提出［1］，它具有机械齿轮所不具备的无接触传动、免维护、振动噪声小等优势,但是受限于当时的磁齿轮结构以及磁性材料的发展，其转矩密度不足以满足工业生产的需求［2］o文献［3］提出了一种基于磁场调制原理的高性能磁齿轮，其利用调制环构造气隙中磁导的变化,使两个转子具有齿轮减速的效果,磁齿轮具有可以和机械齿轮相媲美的转矩密度,得到了广泛的讨论［4-8］。

Danaher-harvard business review 下(中文)

下半部分：英文原文8-17页Danaher Business System (DBS)At the core of Danaher’s operating model and acquisition strategy was the Danaher Business System (DBS). The firm’s investor presentations described DBS as “defining our high-performance culture. DBS is who we are and how we do what we do.” Outsiders noted that DBS “is a set of management tools borrowed liberally from the famed Toyota Production System. In essence it requires every employee, from the janitor to the president, to find ways every day to improve the way works get done.”34 While such programs were “de rigeur for manufacturers for years, the difference at Danaher (was) the company started lean in 1987, one of the earliest U.S. companies to do so, and it has maintained a cultish devotion to making it pay off.”35 The lean approach replaced a traditional “batch-and-queue” manufacturing system with a “single-piece flow” that minimized inprocess time and so reduced inventory and other overhead costs. “In a typical Danaher factory, floors are covered with strips of tape indicating where everything should be, from the biggest machine to the humblest trash can. Managers determine the most efficient place for everything, so a worker won’th ave to walk an extra few yards to pick up a tool, for instance.”36Danaher业务管理系统（DBS）Danaher的操作模型和并购计划的核心便是Danaher业务管理系统（DBS）。

DAMA-Chapter03

The DAMA Guide to The Data ManagementBody of Knowledge (DAMA-DMBOK Guide)First EditionMark Mosley, Editor – Development Michael Brackett, Editor – Production Susan Earley, Assistant Editor Deborah Henderson, Project Sponsor3 Data GovernanceData Governance is the core function of the Data Management Framework shown in Figures 1.3. and 1.4. It interacts with and influences each of the surrounding ten data management functions. Chapter 3 defines the data governance function and explains the concepts and activities involved in data governance.3.1 IntroductionData governance is the exercise of authority and control (planning, monitoring, and enforcement) over the management of data assets. The data governance function guides how all other data management functions are performed. Data governance is high-level, executive data stewardship.The context diagram for the data governance function is shown in Figure 3.1.3.2 Concepts and ActivitiesChapters 1 and 2 state that data management is a shared responsibility between business data stewards, representing stakeholders across the organization, and data professionals, who work on their behalf. Business data stewards are the trustees of enterprise data assets; data management professionals are the expert custodians of © DAMA International 2009 37DAMA-DMBOK Guidethese assets. Effective data management depends on an effective partnership between business data stewards and data management professionals, especially in data governance.Shared decision making is the hallmark of data governance, as shown in Figure 3.2. Effective data management requires working across organizational and system boundaries. Data Governance enables shared responsibility for selected decisions, crossing these boundaries and supporting an integrated view of data. Some decisions are primarily business decisions made with input and guidance from IT, others are primarily technical decisions made with input and guidance from business data stewards at all levels.Figure 3.2 Data Governance Decision Spectrum3.2.1 Data GovernanceData governance is accomplished most effectively as an on-going program and a continual improvement process.Every effective data governance program is unique, taking into account distinctive organizational and cultural issues, and the immediate data management challenges and opportunities. Data governance is a relatively new term, and many organizations continue to pioneer new approaches. Nevertheless, effective data governance programs share many common characteristics, based on basic concepts and principles.Data governance is not the same thing as IT governance. IT governance makes decisions about IT investments, the IT application portfolio, and the IT project portfolio. IT governance aligns the IT strategies and investments with enterprise goals and strategies. CobiT (Control Objectives for Information and related Technology) provides standards for IT governance, but only a small portion of the CobiT framework addresses managing information. Some critical issues, such as Sarbanes-Oxley compliance, span the concerns of corporate governance, IT governance, and data governance. Data governance is focused exclusively on the management of data assets.38 © 2009 DAMA InternationalData Governance Data governance is at the heart of managing data assets. In the circular depiction of theData stewardship is the formal accountability for business responsibilities ensuring effective control and use of data assets. Some of these responsibilities are data governance responsibilities, but there are also significant data stewardship responsibilities within each of the other major data management functions.A data steward is a business leader and / or recognized subject matter expert designated as accountable for these responsibilities. As in other endeavors, a good steward carefully protects, manages, and leverages the resources for which he / she is entrusted.The best data stewards are found, not made. Many of these activities are performed by business professionals even before a formal data stewardship program is implemented. To that extent, data stewardship responsibilities are not new and additional responsibilities for these people. Whenever possible, appoint the people already interested and involved. Their appointment to a data stewardship role is a recognition and confirmation of the work they are already performing. Appointing data stewards formalizes their accountability.Data stewards manage data assets on behalf of others and in the best interests of the organization. Data stewards are appointed to represent the data interests of all stakeholders, including but not limited to, the interests of their own functional © 2009 DAMA International 39DAMA-DMBOK Guide40 © 2009 DAMA Internationaldepartments and divisions. Data stewards must take an enterprise perspective to ensure the quality and effective use of enterprise data.Organizations often differentiate between executive, coordinating, and business data stewards:x Executive data stewards are senior managers who serve on a Data Governance Council.x Coordinating data stewards lead and represent teams of business data stewards in discussions across teams and with executive data stewards. Coordinating data stewards are particularly important in large organizations.x Business data stewards are recognized subject matter experts working with data management professionals on an ongoing basis to define and control data.Data governance is high-level, executive data stewardship. In other words, data governance is the making of high-level data stewardship decisions, primarily by executive and coordinating data stewards.Data stewardship responsibilities exist in data management functions beyond data governance:x Data Architecture Management: Data stewards review, validate, approve, and refine data architecture. Business data stewards define data requirements specifications that data architects organize into the enterprise’s data architecture. Coordinating data stewards help data architects integrate these specifications, resolving differences in names and meanings. Executive data stewards review and approve the enterprise data architecture. Data stewards of all levels and data architects collaborate to maintain data architecture.x Data Development: Business data stewards define data requirements and the specifications that data analysts and architects organize into logical data models. Data stewards also validate physical data models and database designs, participate in database testing and conversion, and ensure consistent use of terms in user documentation and training. Data stewards identify data issues as they arise and escalate when necessary.x Data Operations Management: Business data stewards define requirements for data recovery, retention and performance, and help negotiate service levels in these areas. Business data stewards also help identify, acquire, and control externally sourced data.x Data Security Management: Business data stewards provide security, privacy and confidentiality requirements, identify and resolve data security issues, assist in data security audits, and classify the confidentiality of information in documents and other information products.x Reference and Master Data Management: Business data stewards control the creation, update, and retirement of code values and other reference data, defineData Governance© 2009 DAMA International 41master data management requirements, identify and help resolve master data management issues.x Data Warehousing and Business Intelligence Management: Business data stewards provide business intelligence requirements and management metrics, and they identify and help resolve business intelligence issues.x Document and Content Management: Business data stewards help define enterprise taxonomies and resolve content management issues.x Meta-data Management: Data stewards at all levels create and maintain business meta-data (names, meanings, business rules), define meta-data access and integration needs, and use meta-data to make effective data stewardship and governance decisions. Defining and maintaining business meta-data is at the heart of data stewardship.x Data Quality Management: Improving data quality is an essential part of data stewardship. Business data stewards define data quality requirements and business rules, test application edits and validations, assist in the analysis, certification, and auditing of data quality, lead data clean-up efforts, identify proactive ways to solve root causes of poor data quality, promote data quality awareness, and ensure data quality requirements are met. Data stewards actively profile and analyze data quality in partnership with data professionals.3.2.3 Data Governance and Stewardship OrganizationsData governance guides each of the other data management functions. Every data governance program has a slightly different scope, but that scope may include:x Data Strategy and Policies: Defining, communicating, monitoring.x Data Standards and Architecture: Reviewing, approving, monitoring.x Regulatory Compliance: Communicating, monitoring, enforcing.x Issue Management: Identifying, defining, escalating, resolving.x Data Management Projects: Sponsoring, overseeing.x Data Asset Valuation: Estimating, approving, monitoring.x Communication: Promoting, building awareness and appreciation.Data governance is essentially “the government of data” within the enterprise. Like other governments, there are many different models of data governance – anarchy, dictatorship, and everything in between. Some decisions can be made without risk by individual managers. But the need for shared decision making and risk control drives most organizations to a representative form of data governance, so that all stakeholders and constituencies can be heard.DAMA-DMBOK Guide42 © 2009 DAMA InternationalData management professionals have responsibility for administering data policies, standards, and procedures, for managing and implementing data architecture, for protecting data assets and stakeholder interests, and for providing data management services.In particular, three principles can be drawn from the representative government analogy:1. Data governance includes responsibility for legislative functions (policies andstandards), judicial functions (issue management) and executive functions (administration, services, and compliance).o Data stewardship and governance organizations have responsibility forsetting policies, standards, architecture, and procedures, and for resolvingdata related issues.oData management professional organizations have responsibility foradministering data policies, standards, and procedures, for managing andimplementing data architecture, for protecting data assets andstakeholder interests, and for providing data management services. 2. Data governance typically operates at both enterprise and local levels. In largeorganizations, data governance may also be required at levels in between, depending on the size of the enterprise.3. Separation of duties between Data Stewardship (Legislative and Judicial) andData Management Services (Executive) provides a degree of checks and balances for the management of data.Typically, three cross-functional data stewardship and governance organizations have legislative and judicial responsibilities:x The Data Governance Council has enterprise-wide authority over data management. Executive data stewards sitting on the council are senior managers representing both departmental and enterprise perspectives.x The Data Stewardship Program Steering Committees support the Data Governance Council, much like congressional committees, drafting policies and standards for review and approval by the Data Governance Council regarding specific initiatives, and overseeing these sponsored initiatives.x Data stewardship teams are focused groups of business data stewards collaborating on data stewardship activities within a defined subject area. Data stewardship teams bring together subject matter experts from across the enterprise to determine which data names, definitions, data quality requirements, and business rules should be consistent and what must remain locally unique. Data stewardship teams should be standing, permanent groups that meet regularly, working closely with data architects.The rules defined by data governance organizations include the overall data strategy, data policies, data standards, data management procedures, data management metrics,Data Governance the business data names, business definitions and business rules found in the enterprise data model, additional data requirement specifications, and data quality business rules.The issues adjudicated by data governance organizations include data security issues, data access issues, data quality issues, regulatory compliance issues, policy and standards conformance issues, name and definition conflicts, and data governance procedural issues.Data management professionals perform executive branch responsibilities much like governmental departments and agencies. They administer, monitor and enforce data policies, standards, and procedures. They coordinate, maintain, and implement data architecture. Data management professionals gather and review requirements, facilitate data modeling to serve stakeholder interests, and enable data delivery by implementing databases and applications. They acquire and protect data assets, monitor data quality, and audit data quality and security.In addition to their other professional duties, some data management professionals provide staff support for data governance organizations. Business data stewards are business professionals and managers with part-time stewardship responsibilities. Data management professionals must respect their time and coordinate data governance activity—scheduling meetings, planning and publishing agendas, providing documents for review prior to each meeting, facilitating the meetings, tracking issues, following up on decisions, and publishing meeting minutes. Data architects facilitate each data stewardship team. The Data Management Executive and / or the enterprise data architect may staff Data Stewardship Program Steering Committees. The Data Management Executive and the Chief Information Officer (CIO) guide the Data Governance Council, often with assistance from a Data Governance Office (see 3.2.6 below).At the same time, each organization should be chaired by a business representative. Coordinating data stewards chair their data stewardship teams. An executive data steward from the Data Governance Council should chair each Data Stewardship Coordinating Committee. A Chief Data Steward, selected from among the executive data stewards, chairs the Data Governance Council.Large organizations may have divisional or departmental data governance councils working under the auspices of the Enterprise Data Governance Council. Smaller organizations should try to avoid such complexity.3.2.4 Data Management Services OrganizationsData management professionals within the IT department report to one or more Data Management Services (DMS) organizations. In many enterprises, there may be a centralized DMS organization, while in others there are multiple decentralized groups. Some enterprises have both local DMS organizations as well as a centralized organization. A centralized DMS organization is sometimes known as a Data Management Center of Excellence (COE).© 2009 DAMA International 43DAMA-DMBOK GuideData management professionals within DMS organizations may include data architects, data analysts, data modelers, data quality analysts, database administrators, data security administrators, meta-data administrators, data model administrators, data warehouse architects, data integration architects, and business intelligence analysts. These organizations may also include data integration developers and analytics / report developers, although often they remain in the Application Development organization with other developers. Decentralized organizations may include only a few of these roles. The data management professionals across all organizations constitute a data management professional community, and together with data stewards, they unite in a Data Management Community of Interest (COI).3.2.5 The Data Management ExecutiveThere is no substitute for the leadership of a CIO and a dedicated Data Management Executive, guiding the data management function and promoting the data management program. Visionary and active leadership is a critical success factor for effective data management.The Data Management Executive leads the data management function, serving as the CIO’s right hand for information. The Data Management Executive should report directly to the CIO, responsible for coordinating data management, data stewardship, and data governance. Given the broad scope of the CIO’s responsibilities, the CIO needs one person accountable for managing data and information assets.Data Management Services organizations and their staff should report to the Data Management Executive, directly or indirectly. The Data Management Executive is responsible for data management professional staffing, skills development, contractor management, budgeting and resource allocation, management metrics, data steward recruitment, collaboration across business and IT organizations, and management of the organizational and cultural changes required to support data management. The Data Management Executive works closely with peer leaders of Application Development, Infrastructure / Operations and other IT functions.The Data Management Executive is responsible for implementing the decisions of the Data Governance Council. He or she serves as the operational coordinator for the Data Governance Council, working in close partnership with the Chief Data Steward, by maintaining the data strategy and overseeing data management projects.3.2.6 The Data Governance OfficeIn larger enterprises, The Data Governance Office is a staff organization of data stewardship facilitators who support the activities and decision making of business data stewards at all levels. The purpose of the Data Governance Office is to provide full-time support for part-time business data stewardship responsibilities.Much as a congressional committee is supported by staff professionals, the data stewardship facilitators perform the legwork required to obtain the information that enables business data stewards to make informed and effective decisions. In larger enterprises, the addition of staff responsibilities to data management responsibilities 44 © 2009 DAMA InternationalData Governance may be overwhelming. The Data Management Executive, data architects, and data quality analysts may not be able to find the necessary time to effectively coordinate the communicating, information gathering, and decision making required for data governance and stewardship. When this happens, organizations should consider creating a Data Governance Office.It is critical that full-time data stewardship facilitators do not assume responsibility for data stewardship. Their role is to support the Data Governance Council, Data Stewardship Committees, and Data Stewardship Teams. The Data Governance Office may report to the Data Management Executive, or it may report outside of IT entirely. The diagram in Figure 3.4 depicts these organizations and their relationships.3.3 Data Governance ActivitiesThe activities comprising the data governance function are explained below. Each of the activities is important for fully implementing the data governance function within an3.3.1 Data StrategyA strategy is a set of choices and decisions that together chart a high-level course of action to achieve high-level goals. In the game of chess, a strategy is a sequenced set of © 2009 DAMA International 45moves to win by checkmate or to survive by stalemate. A strategic plan is a high-level course of action to achieve high-level goals.Typically, a data strategy is a data management program strategy–a plan for maintaining and improving data quality, integrity, security, and access. However, a data strategy may also include business plans to use information to competitive advantage and support enterprise goals. Data strategy must come from an understanding of the data needs inherent in the business strategies. These data needs drive the data strategy.Data strategy is not the same thing as data architecture. The decision to define data architecture may be part of a strategy, and the decisions to implement components of data architecture are strategic decisions. The strategy may influence the architecture, which, in turn, supports the strategy, guiding other decisions.In many organizations, the data strategy is owned and maintained by the Data Governance Council, with guidance from the Chief Information Officer and the Data Management Executive. In other organizations, these executives may retain ownership and control of the data strategy; however, sharing ownership builds a data management partnership with the business. Often, the Data Management Executive will draft an initial data strategy even before a Data Governance Council is formed, in order to gain senior management commitment for establishing data stewardship and governance.The components of a data strategy might include:x A compelling vision for data management.x A summary business case for data management, with selected examples.x Guiding principles, values, and management perspectives.x The mission and long-term directional goals of data management.x Management measures of data management success.x Short-term (12-24 months) SMART (specific / measurable / actionable / realistic / time-bound) data management program objectives.x Descriptions of data management roles and organizations, along with a summary of their responsibilities and decision rights.x Descriptions of data management program components and initiatives.x An outline of the data management implementation roadmap (projects and action items).x Scope boundaries and decisions to postpone investments and table certain issues.The data strategy is often packaged into three separate deliverables, including: x A Data Management Program Charter: Overall vision, business case, goals, guiding principles, measures of success, critical success factors, recognized risks, etc.x A Data Management Scope Statement: Goals and objectives for some planning horizon, usually 3 years, and the roles, organizations, and individual leaders accountable for achieving these objectives.x A Data Management Implementation Roadmap: Identifying specific programs, projects, task assignments, and delivery milestones.These deliverables are often published as part of a Data Management Program intranet website.The data strategy should address all data management functions relevant to the organization. For instance, the data strategy should include the meta-data management strategy. See Figure 2.1 for the complete list of data management functions.3.3.2 Data PoliciesData policies are short statements of management intent and fundamental rules governing the creation, acquisition, integrity, security, quality, and use of data and information. Data policies are more fundamental, global, and business critical than detailed data standards. Data policies vary widely across organizations. Data policies describe “what”to do and what not to do, while standards and procedures describe “how” to do something. There should be relatively few data policies, and they should be stated briefly and directly.Data policies are typically drafted by data management professionals. Next, data stewards and management review and refine the policies. The Data Governance Council conducts the final review, revision, and adoption of the data policies. The Data Governance Council may delegate this authority to the Data Stewardship Committee or the Data Management Services Organization.Data policies must be effectively communicated, monitored, enforced, and periodically re-evaluated. Data policies may cover topics such as:x Data modeling and other data development activities within the SDLC.x Development and use of data architecture.x Data quality expectations, roles, and responsibilities (including meta-data quality).x Data security, including confidentiality classification policies, intellectual property policies, personal data privacy policies, general data access and usage policies, and data access by external parties.x Database recovery and data retention.x Access and use of externally sourced data.x Sharing data internally and externally.x Data warehousing and business intelligence policies.x Unstructured data policies (electronic files and physical records).3.3.3 Data ArchitectureThe Data Governance Council sponsors and approves the enterprise data model and other related aspects of data architecture. The Data Governance Council may appoint an Enterprise Data Architecture Steering Committee to oversee the program and its iterative projects. The enterprise data model should be developed and maintained jointly by data architects and data stewards working together in data stewardship teams oriented by subject area, and coordinated by the enterprise data architect.As data stewardship teams propose changes and develop extensions to the enterprise data model, the Data Architecture Steering Committee oversees the project and reviews changes. The enterprise data model should ultimately be reviewed, approved, and formally adopted by the Data Governance Council. Executive data stewards on the Council should pay particular attention to the alignment of the enterprise data model with key business strategies, processes, organizations, and systems.Similarly, the general approach, business case, and less technical aspects of related data architecture should also be reviewed, approved, and adopted by the Data Governance Council. This includes the data technology architecture, the data integration architecture, the data warehousing and business intelligence architecture, and the meta-data architecture. It may also include information content management architecture and enterprise taxonomies. The Council may delegate this responsibility to the Data Architecture Steering Committee.3.3.4 Data Standards and ProceduresData standards and guidelines include naming standards, requirement specification standards, data modeling standards, database design standards, architecture standards, and procedural standards for each data management function. Standards and guidelines vary widely within and across organizations. Data standards are usually drafted by data management professionals. Data standards should be reviewed, approved and adopted by the Data Governance Council, unless this authority is delegated to a Data Standards Steering Committee. Data standards and guidelines must be effectively communicated, monitored, enforced, and periodically re-evaluated. Data management procedures are the documented methods, techniques, and steps followed to accomplish a specific activity or task. Like policies and standards, procedures vary widely across organizations. Procedural documentation is usually drafted by data management professionals, and may be reviewed by a Data Standards Steering Committee.。

the economy of spam

The Economy of SpamMichael Ilger J¨u rgen StraußWilfried GanstererChristian ProschingerSeptember12,2006Technical Report FA384018-6Institute of Distributed and Multimedia SystemsUniversity of ViennaAbstractAlthough many diﬀerent tools are already available which lessen the burden of spam,it sill remains a severe problem.A very promising solu-tion for preventing outgoing spam starts at a diﬀerent point.Spammersshould be driven out of business by creating cost high enough to maketheir work unproﬁtable.In this report we try to show under which cir-cumstances this goal can be reached and we present a tool for analyzingspammers’business models.1MotivationFor the last couple of years every e-mail user had to face the same problem:An ever increasing number of spam messages.As it is a widely accepted fact that spam costs a lot of money,and additionally is very annoying,many diﬀerent approaches have been proposed to decrease the amount of spam,all of them with certain advantages and disadvantages.The most common approach is using aﬁlter for detecting spam messages after they have been ually this approach is based on certain rules,a Bayesﬁlter,or a combination of both[12].Provided that all included elements receive the proper tuning and training suchﬁlters can achieve a high detection rate.They have the advantage of being fairly simple,but the great disadvantage of taking eﬀect only very late, after the message is already accepted by the receiver.Other approaches,like greylisting[8],have the advantage of taking eﬀect a little earlier while providing a similarﬁltering performance but have the disadvantage of introducing delays in the mail delivery process.Instead ofﬁltering messages it is also possible to try to prevent spam mes-sages from being sent by using new protocols or including authentication mech-anisms in existing protocols[9].While such a solution promises good results,1it has the extreme disadvantage of requiring a complete replacement of all e-mail software globally,which is unrealistic.Finally,a number of laws has been passed to prosecute spammers[10][13],and newspapers have featured headlines about spammers being caught and brought to trial.Still,this did not solve the problem.One important aspect has not received the amount of attention which it deserves.While only a small number of spam messages is sent out“just for fun”, the vast majority of spam has one simple purpose:to return proﬁt.Currently, with messaging cost being close to zero,it is possible to create proﬁt with a very low response rate(see Section4.3).The goal in this report is to take a closer look at the cost a spammer is facing when sending out a certain amount of messages.We will also try to relate this to the cost a regular user is facing when using e-mail in order toﬁnd economical barriers which impede spammers while being unnoticed by a regular user[5].With the knowledge gained here it is possible to create new tools for outgoing spam prevention which can help internet service providers(ISPs)to reduce the load on their servers as well as to secure their reputation by preventing spamming originating from their network. 2Analyzing Spammers’Business Model Obviously spammers want to make proﬁt.The only way to stay in business is to create income which is higher than the total expenses.This leads to two simple options for stopping spam:Either restricting the potential income from spamming(but this is hard to achieve),or raising the cost for sending out spam high enough to make such business unproﬁtable.The diﬀerent business models motivating the spam phenomenon have already been summarized in[3][4].In the following sections we will focus on an overview of the bills a spammer has to pay at the end of the day as well as on diﬀerent approaches for raising his cost.2.1Cost-based Anti-spam ApproachesWhile money is theﬁrst thing that comes to mind when talking about“cost”, cost-based anti-spam approaches do not necessarily involve money directly. Even though creating(paid)stamps for e-mail messages is one of the exist-ing approaches[1][11](with the money preferably donated to charity),it is not the only way of payment.In[5]we adapted a token-bucket strategy,which is traditionally used for traﬃc shaping,toﬁt the needs of e-mail traﬃc regula-tion.It is based on creating its own“currency”(tokens)for e-mail messages and includes a starting seed as well as a certain reﬁll rate.Each message sent consumes a certain number of tokens.This implementation allows to impede heavy-duty users while remaining unnoticed by common users.Similarly,other approaches require users to solve certain puzzles to be able to send a message.These puzzles may depend on human interaction or require2the computer to do certain computations[6].In both situations human users can easily meet the requirements whereas mass-mailers cannot.2.2Cost Factors for SpammersBefore diﬀerent cost and proﬁt models can be analyzed,the most important cost and revenue factors must be identiﬁed.The cost factors for a spammer can be grouped in four categories—hardware cost H,software cost S,operating cost O,and labor cost L.Figure1provides an overview of the most important cost factors.Some cost,such as hardware cost,are easy to measure,but others can only be estimated(software installation duration,time to compose a spam e-mail).The basic cost model for a spammer is thus deﬁned as:total cost c=H+S+O+L.Assuming a single spammer uses his own home equipment,hardware cost H can be deﬁned as the sum of the cost C for a computer,M for a monitor,and P for peripheral devices:H=C+M+P.Software cost S can be divided into cost for basic software which every com-puter needs(like cost OS for the operating system)and cost for software for special spamming activities,like cost R for remailers,cost MAH for mail address harvesters or cost WH for web hosting:S=OS+R+MAH+W H.Operating cost O is a sum of internet service cost I,electricity cost E for running the system,address collection cost A(addresses can be bought or self-collected) and open proxy cost OP:O=I+E+A+OP.Labor cost L can be divided into cost IN for installation,cost MT for mainte-nance,cost MP for mail production,and cost AC for acquiring customers:L=IN+MT+MP+AC.All these cost factors must be measured or estimated for a certain period of time(for example,per day).The resulting daily cost is then divided by the number of messages which are sent out in this period of time in order to determine the per message cost.2.3Revenue Factors for SpammersWhile the cost factors can be estimated relatively easily,revenue factors are very hard to deﬁne and determine,because spammers usually do not declare their business model in public.Nevertheless,it is clear that there are two main3Figure1:Cost factors for spammmerspayment schemes—a brokerage system,where the marketer gets a fee per item sold and a pay-per-mail campaign system(the spammer receives money for an e-mail campaign to a certain number of customers).As it is not possible to get representative and reliable data about the former the investigation presented here focuses on the mail campaign system.As discussed in[4],a good estimate for the average revenue per message sent out is0.00434Euro.3The SpamSim ToolIn order to design and to calibrate an anti-spam method which is capable of interfering with these business models,we created the simulation tool SpamSim. This tool allows us to model the eﬀects of various parameters on the proﬁt achieved by spammers.3.1System OverviewOur tool implements the most important cost and proﬁt factors and models their interdependencies.Based on this tool,we try to answer central questions,such as how many messages must beﬁltered out,or how many messages a spammer has to send to be proﬁtable.By examining the break-even point for spammers in terms of cost and proﬁt,we can evaluate the eﬀectivity of anti-spam methods.The SpamSim tool has been implemented as a Windows GUI application, programmed in Visual C#operating on the framework.The in-terface is currently only available in the German language.Future versions may also provide the logic of this program as a web-service with an English user inter-face.To provide aﬂexible solution the scenarios are deﬁned in MathML—each scenario is deﬁned by the elements of the cost factors.MathML(Mathematical Markup Language)is an application of XML which includes additional elements4Figure2:Graphical output of SpamSimfor calculations.The SpamSim tool has a standard and an advanced mode—the advanced mode allowsﬁne tuning of all parameters,whereas the standard mode uses default values for many parameters.The results of the simulation can be displayed as a line diagram or exported as an XML or CSVﬁle.3.2Conﬁguration DetailsSpamSim consists of an executableﬁle,a library which is used to create graphics, and a conﬁgurationﬁle.The conﬁgﬁle provides the path to further inputﬁles. One of this inputﬁles determines the factors and default values used for the computation,while three more for each scenario provide the formulae used to compute the values shown on the x and y axis of the diagrams.The program itself features four diﬀerent views.These views include a pref-erences window to choose the right conﬁguration and an editor which allows for easy access to the scenario as an xmlﬁle.The cost can be modeled in the main window.Finally,a scenario window as shown in Figure2provides the graphical solution.3.3Tool UsageUsing SpamSim is relatively simple.It does not require an installation,but instead only an entry for the installation path in the conﬁgurationﬁle.The5currently easiest and fastest way to create an xmlﬁle which is used as input for the program is to modify an existingﬁle with a regular text editor.Optionally, parameter values may also be edited within the application.Oneﬁle contains all the scenarios with their parameters and default values.Itsﬁle path is part of the conﬁgurationﬁle.Optionally it is possible to save and load the values of a certain scenario.The calculations for each scenario are deﬁned in a total of three diﬀerentﬁles.Eachﬁlename begins with the scenario name and is followed by a certain usage convention.One is used to deﬁne the stepping along the x-axis.The other twoﬁles include the cost and revenue formulas for the scenarios deﬁned earlier.In the following section,three diﬀerent scenarios are discussed in more de-tail.All of them were implemented with SpamSim,and theﬁgures shown for illustration were created with the tool.4Selected Case StudiesIn this section we describe three diﬀerent scenarios of spamming activity and possible solutions to destroy spammers’business models.It is clear that the proﬁt of a spammer dependends on the number of messages sent out.First we analyze the inﬂuence of a token bucket algorithm as described in[5]which dynamically limits outgoing spam traﬃc(from ISP side),second we investigate the impact ofﬁlter performance and third we explore the leverage of the response rate on spammers’business.4.1Scenario1This scenario provides a simple example of a spammer who uses his own home PC and a leased line for spamming.The corresponding expense factors are listed in Table1.We assume that hardware,software,operating cost and working cost are monthlyﬁxed cost.Only open proxy cost,which are paid per e-mail sent out,can be denoted as running cost.If the upload line has a bandwidth of approximately256KBit/sec,if we assume an average size of a spam message around4Kbyte(this average size is based on the analysis of approximately1000000spam messages[2]),and if we ignore all overhead data,a spammer is able to send out around691200messages per day(or20736000messages per month).Figure3shows the cost and the revenue in this scenario.The cost curve is taken from the above data,and the revenue curve is based on a revenue of0.00434Euro per e-mail[4].Figure3 clearly demonstrates that the spammer can make a huge proﬁt if there is no restriction.Restricting the outgoing traﬃc to10000messages per day leads to the dia-gram shown in Figure4.It can be clearly seen that the cost and revenue curves intersect close to250000messages sent out per month.Below the spammer does not make any proﬁt.6Type of cost Total cost[Euro]Life time[month]Monthly cost[Euro] Fixed costHardwareAverage computer1000.-3627.78 Average Monitor300.-368.34 Peripherals200.-36 5.55 SoftwareOperating system 1.-360.027 (open source)Harvester50.-36 1.38 ReMailer100.-36 2.77 Homepage20.-120.00 Operating costISP cost49.-149.00 Electricity35.-135.00 Addresses300.-1225.00 Working costInstallation30.-12 2.50 Maintenance300.-1300.00 Mail-design300.-1300.00 Customer recruitment300.-1300.00 sum ofﬁxed cost:1077.36 Variable costOpen proxy0.000125per mailTable1:Cost factors for a single spammer(scenario1)e-mail sent[×103]cost[Euro]revenue[Euro]01077.360.00251080.48108.50501083.61217.00751086.73325.501001089.86434.001251092.98542.501501096.11651.001751099.23759.502001102.36868.002251105.48976.502501108.611085.00Table2:Cost factors single spammer scenario1limit=84007Figure3:Cost(printed in red)and revenue(printed in green)spammer(scenario 1,no limit)Figure4:Cost(printed in red)and revenue(printed in green)spammer(scenario 1,limited to10000messages per day)8Figure5:Cost(printed in red)and revenue(printed in green)spammer(scenario 1,limited to8400messages per day)Table2and Figure5show the cost and revenue data for a limit of8400 messages.In this case,the revenue always stays below the cost.Consequently,in the given scenario(single spammer)weﬁnd that a restriction of outgoing traﬃc to less than8400messages per day will destroy spammers’business model. 4.2Scenario2This scenario describes a single spammer,who uses a leased line to connect to a leased server called LegalMail.1The spammer connects remotely to this server. The server then sends out user deﬁned messages.Table3shows the cost factors for this scenario.Unlike scenario1there are noﬁxed cost—all the monthly cost are divided through the amount of e-mail sent and afterwards compared to the revenue.LegalMail guarantees that under certain conditions(size of the messages, not too many invalid addresses)a minimum of30000000messages is sent out per month.The total monthly cost are2018.42Euro.Thus,one message costs 0.000067Euro,but brings0.00434Euro of revenue.As Figure6shows that the revenue can be huge if no countermeasures are taken.In this scenario we show how important the spamﬁlter performance is for harming spammers’business.The better theﬁlter performance the smaller is the proﬁt.Quantitatively speaking,with aﬁlter performance of90%spammers 1/bulk-email-software/legalmail/legalmail.html9Type of cost Total cost[Euro]Life time[month]Monthly cost[Euro] Fixed costHardwareAverage computer1000.-3627.78 Average Monitor300.-368.34 Peripherals200.-36 5.55 SoftwareOperating system 1.-360.027 (open source)Homepage200.-36 5.55 Operating costISP cost35.-135.00 Electricity17.-117.00 Addresses200.-1216.67 LegalMail1000.-11000.00 Working costInstallation30.-12 2.50 Maintenance300.-1300.00 Mail-design300.-1300.00 Customer recruitment300.-1300.00 sum ofﬁxed cost:2018.42 Table3:Cost factors single spammer(scenario2)10Figure6:Cost(printed in red)and revenue(printed in green)spammer(scenario 2,no spamﬁlter)are still making proﬁt(see Figure7).Only if theﬁlter achieves a detection rate of97,45%or more,spamming becomes unproﬁtable(see Figure8and Table4).4.3Scenario3This scenario describes the same spammer as in scenario1,but this spammer does not get his revenue from sending out e-mail.Instead,he advertizes by e-mail and is paid per item sold.In this example we describe the inﬂuence of the response rate on the spammers’business model.Let us assume that the spammer gets a provision of8Euro per item sold and that the response rate is0.036%(the spammer sells one item per2777messages sent out[3]).Then the resulting graph looks as shown in Figure9.The same scenario with a lower response rate of0.001%is shown in Figure10.With a response rate of0.00001%(cf.[7])the spammer could never generate any proﬁt in this scenario.Table5shows that the break-even point is close to a response rate of0.002%(which corresponds to one out of50000messages leading to a successful business transaction).A discussion of estimated response rates is also included in[4].11Figure7:Cost(printed in red)and revenue(printed in green)spammer(scenario 2,spamﬁlter with detection rate90%)Figure8:Cost(printed in red)and revenue(printed in green)spammer(scenario 2,spamﬁlter with detection rate98%)12e-mail sent[×109]cost[Euro]revenue[Euro]3201.84201.816403.86403.629605.53605.43181211.051210.86271816.581816.29302018.422018.10Table4:Cost factors single spammer(scenario2,spamﬁlter with detection rate97.45%)Figure9:Cost(printed in red)and revenue(printed in green)spammer(scenario 3,response rate0.0036%)13Figure10:Cost(printed in red)and revenue(printed in green)spammer(sce-nario3,response rate0.001%)e-mail sent[×109]cost[Euro]revenue[Euro]0.00883.190.002.071142.39331.784.141401.59663.556.221660.79995.338.291919.991327.1010.362179.191658.8812.442438.391990.6614.542697.592322.4316.592956.792654.2118.663215.992985.9820.733475.193317.76Table5:Cost factors single spammer(scenario3,response rate0.002%)145Conclusions and Future WorkDetailed information on the relevant cost and revenue factors in the spammers’business model is very important when trying to stop spam,especially as it allows to predict which anti-spam strategies can be expected to be eﬀective.In this report,it has been shown how to utilize this information for evalu-ating anti-spam methods and strategic decisions.In particular,the SpamSim tool has been presented which allows for quantitative modelling the business model underlying ing this tool,the economic aspects of three dif-ferent spamming scenarios and anti-spam strategies(restricting outgoing traﬃc,ﬁltering,reducing response rates)have been analyzed.Based on this work,we plan to analyze the cost caused by spam from an overall economic point of view which also includes the cost created by spam-prevention.Factoring in detailed information on various cost factors also allows for a new approach to many pre-send techniques.This is expected to lead to a ﬁne tuning of these approaches which boosts their performance.This in turn will make it much harder for spammers to circumvent these anti-spam methods and at the same time makes them fully transparent to regular users. Acknowledgments.We would like to express our gratitude to Internet Pri-vatstiftung Austria,mobilkom austria,UPC Telekabel,and Internet Service Providers Austria for supporting this research.References[1]Capek,P.,Leiba, B.,Wegman,M.,and Fahlmann,S.Charitybegins at...your mail program,2004.http://domino.research.ibm.com/comm/research projects.nsf/pages/spam.papers.html/$FILE/ charity-seals.pdf.[2]Daberger,M.Quantitative Untersuchungen der Eigenschaften von Un-solicited Bulk E-Mail und Unsolicited Commercial E-Mail.Master’s thesis, Institute of Distributed and Multimedia Systems,Faculty of Computer Sci-ence,University of Vienna,June2006.[3]Gansterer,W.,Ilger,M.,Lechner,P.,Neumayer,R.,andStrauß,J.Anti-spam methods—state of the art.Technical Report FA384018-1,Institute of Distributed and Multimedia Systems,Faculty of Computer Science,University of Vienna,Mar.2005.[4]Gansterer,W.,Ilger,M.,Lechner,P.,Neumayer,R.,andStrauß,J.Phases2and3of project’Spamabwehr’:SMTP based con-cepts and cost-proﬁt models.Technical Report FA384018-2,Institute of Distributed and Multimedia Systems,Faculty of Computer Science,Uni-versity of Vienna,2005.[5]Gansterer,W.N.,Hlavacs,H.,Ilger,M.,Lechner,P.,andStrauß,J.Token buckets for outgoing spam prevention.In Proceedings of15the IASTED International Conference on Communication,Network,and Information Security(CNIS2005)(Nov.2005),M.Hamza,Ed.,IASTED, ACTA Press.[6]Goodman,J.T.,and Rounthwaite,R.Stopping outgoing spam.InACM Conference on Electronic Commerce(2004),pp.30–39.[7]Graham,P.A plan for spam,2002./stopspam.html.[8]Harris, E.The next step in the spam control war:Greylisting.Tech.rep.,PureMagic Software,2003./ greylisting/whitepaper.html.[9]Lechner,P.Das Simple Mail Transfer Protokoll und die Spamprob-lematik.Master’s thesis,Institute of Distributed and Multimedia Systems, Faculty of Computer Science,University of Vienna,June2005.[10]Lee,Y.The can-spam act:a silver bullet solution?Commun.ACM48,6(2005),131–132.[11]Loder,T.,van Alstyne,M.W.,and Wash,R.An economic answer tounsolicited communication.In ACM Conference on Electronic Commerce (2004),pp.40–50.[12]Schryen,G.Eﬀektivitaet von Loesungsansaetzen zur Bekaempfung vonSpam.Wirtschaftsinformatik46,4(2004),8.[13]Sipior,J.C.,Ward,B.T.,and Bonner,P.G.Should spam be onthe menu?Commun.ACM47,6(2004),59–63.16。

HMReview-HobbyMerchandiser

duced. Each of these fine kits includes a comprehensive instruction manual with step-by-step written instructions andisometric drawings; a rough-carved, solid basswood hull;simulated deck planking; laser-cut wood parts; cast white metal hatches, companionways, anchors and windlass;rigging thread in appropriate weights and colors, and all the factory-drilled blocks and deadeyes needed to com-plete the standing or running rigging. The two fully rigged models I examined also provide rolled, full-size plans and a sheet of full-size hull templates.Model Shipways offers a wide selection of plank-on-frame models, too, from the fully-rigged 28” Rattlesnake to “Old Ironsides,” the U.S.S. Constitution. Despite the appeal of these magnificent vessels, first-time ship model-ers should be steered toward one of Model Shipways’three solid models. Venturing into ship modeling with the Taurus Steam Towboat, the Phantom New York Pilot Boat or the Colonial Schooner Sultana will all but assure beginners of a better-than-average completed project.Like me, I’m sure that many of you will also fondly remember the solid hull Model Shipways kits in those long, yellow boxes. However, some of you may not be aware that Model Expo purchased the Model Shipwaysfactory in 1984. Since the shift in the company’s owner-ship and direction, a lot more has changed than just the color and shape of the kit boxes.Many of the original designs have been converted from solid hull to plank-on-frame projects, and several new additions were made to the lineup, including popular,traditional favorites like the Charles W . Morgan, Pride of Baltimore II, an Armed Virginia Sloop and the U.S.S.Constitution.Although Model Expo has taken every opportunity to improve and ultimately perfect their offerings, they arealso bringing back many of their solid hull models in the original form. The compact yellow boxes will remain a part of history forever, but the Model Shipways Classics line will be identical to the originals in every other way.If quality sailing ship kits for modelers isn’t enough,Model Shipways has several perks for hobby dealers, too.Their Captain’s Quarters program is available to dealers who order just one each of their 16 wooden ships kits.CQ dealers get discounts of at least 40 percent, listings on the back of Model Expo Historical Ship Model catalogs,and listings in ad campaigns appearing in national hobby magazines and on the Model Expo Web site.It’s just not possible for anyone to see a masterfully built model ship and not pause to admire it. Sailing ves-sels are an art form unto themselves, and I would be sur-prised if there is not a budding ship modeler lying dor-mant in every RC, railroad and plastics builder you serve.For more informationabout Model Shipways and the Captain’s QuartersDealer program, see the ad on page 31, or call Model Expo in Hollywood, Florida,at 800-344-4406. HMFittings are plentiful, and come in a com-bination of cast white metal, copper and brass. appropriate rigging thread is also provided in each kit.HOBBY MERCHANDISER APRIL 2005 25Model Shipways offers kits in both the solid hull and plank-on-frame formats. Solid hull models feature carved, basswood hulls with roughly defined bulwarks.Model Shipways provides first-class instructional materials with each kit, including an illustrated instruction manual and a set of hull templates..Wood parts include simulated planking sheets for decks, strip wood for cabin and hull detail, andlaser-cut mast caps and assorted accessory parts.Detail is evident in this fin-ished rendition of Model Shipways’ Sultana, a Colonial schooner circa 1767.。

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