Generalized link properties for expressive E-connections of description logics

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《软件工程》习题汇锦

《软件工程》习题汇锦一、单项选择题提示：在每小题列出的四个备选项中只有一个是符合题目要求的，请将其代码填写在下表中。

错选、多选或未选均无分.1. ( ）If a system is being developed where the customers are not sure of what theywant, the requirements are often poorly defined。

Which of the following would be an appropriate process model for this type of development?（A）prototyping（B）waterfall（C)V-model（D）spiral2. （)The project team developing a new system is experienced in the domain.Although the new project is fairly large, it is not expected to vary much from applications that have been developed by this team in the past. Which process model would be appropriate for this type of development？（A）prototyping（B）waterfall（C）V-model（D）spiral3. （）Which of the items listed below is not one of the software engineering layers?(A）Process（B）Manufacturing（C）Methods（D)T ools4. （)Which of these are the 5 generic software engineering framework activities？（A）communication，planning，modeling，construction，deployment（B) communication, risk management, measurement，production, reviewing(C）analysis，designing，programming, debugging, maintenance（D）analysis, planning，designing，programming，testing5. （）The incremental model of software development is（A）A reasonable approach when requirements are well defined.(B）A good approach when a working core product is required quickly。

Generalized network design problems

Generalized Network Design ProblemsbyCorinne Feremans1,2Martine Labb´e1Gilbert Laporte3March20021Institut de Statistique et de Recherche Op´e rationnelle,Service d’Optimisation,CP210/01, Universit´e Libre de Bruxelles,boulevard du Triomphe,B-1050Bruxelles,Belgium,e-mail: mlabbe@smg.ulb.ac.be2Universiteit Maastricht,Faculty of Economics and Business Administration Depart-ment,Quantitative Economics,P.O.Box616,6200MD Maastricht,The Netherlands,e-mail:C.Feremans@KE.unimaas.nl3Canada Research Chair in Distribution Management,´Ecole des Hautes´Etudes Com-merciales,3000,chemin de la Cˆo te-Sainte-Catherine,Montr´e al,Canada H3T2A7,e-mail: gilbert@crt.umontreal.ca1AbstractNetwork design problems consist of identifying an optimal subgraph ofa graph,subject to side constraints.In generalized network design prob-lems,the vertex set is partitioned into clusters and the feasibility conditionsare expressed in terms of the clusters.Several applications of generalizednetwork design problems arise in theﬁelds of telecommunications,trans-portation and biology.The aim of this review article is to formally deﬁnegeneralized network design problems,to study their properties and to pro-vide some applications.1IntroductionSeveral classical combinatorial optimization problems can be cast as Network Design Problems(NDP).Broadly speaking,an NDP consists of identifying an optimal subgraph F of an undirected graph G subject to feasibility conditions. Well known NDPs are the Minimum Spanning Tree Problem(MSTP),the Trav-eling Salesman Problem(TSP)and the Shortest Path Problem(SPP).We are interested here in Generalized NDPs,i.e.,in problems where the vertex set of G is partitioned into clusters and the feasibility conditions are expressed in terms of the clusters.For example,one may wish to determine a minimum length tree spanning all the clusters,a Hamiltonian cycle through all the clusters,etc.Generalized NDPs are important combinatorial optimization problems in their own right,not all of which have received the same degree of attention by operational researchers.In order to solve them,it is useful to understand their structure and to exploit the relationships that link them.These problems also underlie several important applications areas,namely in theﬁelds of telecommu-nications,transportation and biology.Our aim is to formally deﬁne generalized NDPs,to study their properties and to provide examples of their applications.We willﬁrst deﬁne an uniﬁed notational framework for these problems.This will be followed by complexity results and by the study of seven generalized NDPs.2Deﬁnitions and notationsAn undirected graph G=(V,E)consists of aﬁnite non-empty vertex set V= {1,...,n}and an edge set E⊆{{i,j}:i,j∈V}.Costs c i and c ij are assigned to vertices and edges respectively.Unless otherwise speciﬁed,c i=0for i∈V and c ij≥0for{i,j}∈E.We denote by E(S)={{i,j}∈E:i,j∈S},the subset of edges having their two end vertices in S⊆V.A subgraph F of G is denoted2by F=(V F,E F),V F⊆V,E F⊆E(V F),and its cost c(F)is the sum of its vertex and edge costs.It is convenient to deﬁne an NDP as a problem P associated with a subset of terminal vertices T⊆V.A feasible solution to P is a subgraph F=(V F,E F),where T⊆V F,satisfying some side constraints.If T=V,then the NDP is spanning;if T⊂V,it is non-spanning.Let G(T)=(T,E(T))and denote by F P(T)the subset of feasible solutions to the spanning problem P de-ﬁned on the graph G(T).Let S⊆V be such that S∩T=∅,and denote by F P(T,S)the set of feasible solutions of the non-spanning problem P on graph G(S∪T)that spans T,and possibly some vertices from S.In this framework,feasible NDP solutions correspond to a subset of edges satisfying some constraints.Natural spanning NDPs are the following.1.The Minimum Spanning Tree Problem(MSTP)(see e.g.,Magnanti andWolsey[45]).The MSTP is to determine a minimum cost tree on G that includes all the vertices of V.This problem is polynomially solvable.2.The Traveling Salesman Problem(TSP)(see e.g.,Lawler,Lenstra,RinnooyKan and Shmoys[42]).The TSP consists ofﬁnding a minimum cost cycle that passes through each vertex exactly once.This problem is N P-hard.3.The Minimum Perfect Matching Problem(MPMP)(see e.g.,Cook,Cun-ningham,Pulleyblank and Schrijver[8]).A matching M⊆E is a subset of edges such that each vertex of M is adjacent to at most one edge of M.A perfect matching is a matching that contains all the vertices of G.The problem consists ofﬁnding a perfect matching of minimum cost.This problem is polynomial.4.The Minimum2-Edge-Connected Spanning Network(M2ECN)(see e.g.,Gr¨o tschel,Monma and Stoer[26]and Mahjoub[46].The M2ECN consists ofﬁnding a subgraph with minimal total cost for which there exists two edge-disjoint paths between every pair of vertices.5.The Minimum Clique Problem(MCP).The MCP consists of determining aminimum total cost clique spanning all the vertices.This problem is trivial since the whole graph corresponds to an optimal solution.We also consider the following two non-spanning NDPs.1.The Steiner Tree Problem(STP)(see Winter[61]for an overview).TheSTP is to determine a tree on G that spans a set T of terminal vertices at minimum cost.A Steiner tree may contain vertices other than those of T.These vertices are called the Steiner vertices.This problem is N P-hard.32.The Shortest Path Problem(SPP)(see e.g.,Ahuja,Magnanti and Orlin[1]).Given an origin o and a destination d,o,d∈V,the SPP consists of deter-mining a path of minimum cost from o to d.This problem is polynomially solvable.It can be seen as a particular case of the STP where T={o,d}.In generalized NDPs,V is partitioned into clusters V k,k∈K.We now formally deﬁne spanning and non-spanning generalized NDPs.Deﬁnition1(“Exactly”generalization of spanning problem).Let G= (V,E)be a graph partitioned into clusters V k,k∈K.The“exactly”generaliza-tion of a spanning NDP P on G consists of identifying a subgraph F=(V F,E F) of G yieldingmin{c(F):|V F∩V k|=1,F∈F P( k∈K(V F∩V k))}.In other words,F must contain exactly one vertex per cluster.Two diﬀer-ent generalizations are considered for non-spanning NDPs.Deﬁnition2(“Exactly”generalizations of non-spanning problem).Let G=(V,E)be a graph partitioned into clusters V k,k∈K,and let{K T,K S}be a partition of K.The“exactly”T-generalization of a non-spanning problem NDP P on G consists of identifying a subgraph F=(V F,E F)of G yielding min{c(F):|V F∩V k|=1,k∈K T,F∈F P( k∈K T(V F∩V k), k∈K S V k)}.The“exactly”S-generalization of a non-spanning problem NDP P on G consists of identifying a subgraph F=(V F,E F)of G yieldingmin{c(F):|V F∩V k|=1,k∈K S,F∈F P( k∈K T V k, k∈K S(V F∩V k))}.In other words,in the“exactly”T-generalization,F must contain exactly one vertex per cluster V k with k∈K T,and possibly other vertices in k∈K S V k.In the“exactly”S-generalization,F must contain exactly one vertex per cluster V k with k∈K S,and all vertices of k∈K T V k.We can replace|V F∩V k|=1in the above deﬁnitions by|V F∩V k|≥1 or|V F∩V k|≤1,leading to the“at least”version or“at most”version of the generalization.The“exactly”,“at least”and“at most”versions of a generalized NDP P are denoted by E-P,L-P and M-P,respectively.In the“at most”and in the“exactly”versions,intra-cluster edges are neglected.In this case,we call the graph G,|K|-partite complete.In the“at least”version the intra-cluster edges are taken into account.43Complexity resultsWe provide in Tables1and2the complexity of the generalized versions in their three respective forms(“exactly”,“at least”and“at most”)for the seven NDPs considered.Some of these combinations lead to trivial problems.Obviously,if a classical NDP is N P-hard,its generalization is also N P-hard.The indication“∅is opt”means that the empty set is feasible and is optimal for the correspond-ing problem.References about complexity results for the classical version of the seven problems considered can be found in Garey and Johnson[20].As can be seen from Table2,two cases of the generalized SPP are N P-hard by reduction from the Hamiltonian Path Problem(see Garey and Johnson[20]). Li,Tsao and Ulular[43]show that the“at most”S-generalization is polynomial if the shrunk graph is series-parallel but provide no complexity result for the gen-eral case.A shrunk graph G S=(V S,E S)derived from a graph G partitioned into clusters is deﬁned as follows:V S contains one vertex for each cluster of G, and there exists an edge in E S whenever an edge between the two corresponding clusters exists in G.An undirected graph is series-parallel if it is not contractible to K4,the complete graph on four vertices.A graph G is contractible to an-other graph H if H can be obtained from G by deleting and contracting edges. Contracting an edge means that its two end vertices are shrunk and the edge is deleted.We now provide a short literature review and applications for each of the seven generalized NDPs considered.Table1:Complexity of classical and generalized spanning NDPs Problem MSTP TSP MPMP M2ECN MCP Classical Polynomial N P-hard Polynomial N P-hard Trivial,polynomial Exactly N P-hard[47]N P-hard Polynomial N P-hard N P-hard(with vertexcost)[35]At least N P-hard[31]N P-hard Polynomial N P-hard Equivalent toexactlyAt most∅is opt∅is opt∅is opt∅is opt∅is opt5Table2:Complexity of classical and generalized non-spanning NDPsProblem STP SPPClassical N P-hard PolynomialExactly T-generalization N P-hard PolynomialExactly S-generalization N P-hard N P-hardAt least T-generalization N P-hard PolynomialAt least S-generalization N P-hard N P-hardAt most T-generalization∅is opt∅is optAt most S-generalization N P-hard Polynomial if shrunk graphis series-parallel[43]4The generalized minimum spanning tree prob-lemThe Generalized Minimum Spanning Tree Problem(E-GMSTP)is the problemofﬁnding a minimum cost tree including exactly one vertex from each vertexset from the partition(see Figure1a for a feasible E-GMSTP solution).Thisproblem was introduced by Myung,Lee and Tcha[47].Several formulations areavailable for the E-GMSTP(see Feremans,Labb´e and Laporte[17]).The Generalized Minimum Spanning Tree Problem in its“at least”version(L-GMSTP)is the problem ofﬁnding a minimum cost tree including at least onevertex from each vertex set from the partition(see Figure1b for a feasible solu-tion of L-GMSTP).This problem was introduced by Ihler,Reich and Widmayer[31]as a particular case of the Generalized Steiner Tree Problem(see Section9)under the name“Class Tree Problem”.Dror,Haouari and Chaouachi[11]showthat if the family of clusters covers V without being pairwise disjoint,then theL-GMSTP deﬁned on this family can be transformed into the original L-GMSTPon a graph G′obtained by substituting each vertex v∈ ℓ∈L Vℓ,L⊆K by|L| copies vℓ∈Vℓ,ℓ∈L,and adding edges of weight zero between each pair of thesenew vertices(clique of weight zero between vℓforℓ∈L).This can be done aslong as there is noﬁxed cost on the vertices,and this transformation does nothold for the“exactly”version of the problem.Applications modeled by the E-GMSTP are encountered in telecommuni-cations,where metropolitan and regional networks must be interconnected by atree containing a gateway from each network.For this internetworking,a vertexhas to be chosen in each local network as a hub and the hub vertices must be con-nected via transmission links such as opticalﬁber(see Myung,Lee and Tcha[47]).6Figure 1a: E−GMSTP Figure 1b: L−GMSTPFigure1:Feasible GMSTP solutionsThe L-GMSTP has been used to model and solve an important irrigation network design problem arising in desert environments,where a set of|K|poly-gon shaped parcels share a common source of water.Each parcel is represented by a cluster made up of the polygon vertices.Another cluster corresponds to the water source vertex.The problem consists of designing a minimal length irriga-tion network connecting at least one vertex from each parcel to the water source. This irrigation problem can be modeled as an L-GMSTP as follows.Edges corre-spond to the boundary lines of the parcel.The aim is to construct a minimal cost tree such that each parcel has at least one irrigation source(see Dror,Haouari and Chaouachi[11]).Myung,Lee and Tcha[47]show that the E-GMSTP is strongly N P-hard, using a reduction from the Node Cover Problem(see Garey and Johnson[20]). These authors also provide four integer linear programming formulations.A branch-and-bound method is developed and tested on instances involving up to 100vertices.For instances containing between120and200vertices,the method is stopped before theﬁrst branching.The lower bounding procedure is a heuris-tic method which approximates the linear relaxation associated with the dual of a multicommodityﬂow formulation for the E-GMSTP.A heuristic algorithm ﬁnds a primal feasible solution for the E-GMSTP using the lower bound.The branching strategy performed in this method is described in Noon and Bean[48].A cluster isﬁrst selected and branching is performed on each vertex of this cluster.In Faigle,Kern,Pop and Still[14],another mixed integer formulation for the E-GMSTP is given.The linear relaxation of this formulation is computed for a set of12instances containing up to120vertices.This seems to yield an7optimal E-GMSTP solution for all but one instance.The authors also use the subpacking formulation from Myung,Lee and Tcha[47]in which the integrality constraints are kept and the subtour constraints are added dynamically.Three instances containing up to75vertices are tested.A branch-and-cut algorithm for the same problem is described in Feremans[15].Several families of valid inequalities for the E-GMSTP are introduced and some of these are proved to be facet deﬁputational results show that instances involving up to200vertices can be solved to optimality using this method.A comparison with the computational results obtained in Myung,Lee and Tcha[47]shows that the gap between the lower bound and the upper bound obtained before branching is reduced by10%to20%.Pop,Kern and Still[51]provide a polynomial approximation algorithm for the E-GMSTP.Its worst-case ratio is bounded by2ρif the cluster size is bounded byρ.This algorithm is derived from the method described in Magnanti and Wolsey[45]for the Vertex Weighted Steiner Tree Problem(see Section9).Ihler,Reich,Widmayer[31]show that the decision version of the L-GMSTP is N P-complete even if G is a tree.They also prove that no constant worst-case ratio polynomial-time algorithm for the L-GMSTP exists unless P=N P,even if G is a tree on V with edge lengths1and0.They also develop two polynomial-time heuristics,tested on instances up to250vertices.Finally,Dror,Haouari and Chaouachi[11]provide three integer linear programming formulations for the L-GMSTP,two of which are not valid(see Feremans,Labb´e and Laporte[16]). The authors also describeﬁve heuristics including a genetic algorithm.These heuristics are tested on20instances up to500vertices.The genetic algorithm performs better than the other four heuristics.An exact method is described in Feremans[15]and compared to the genetic algorithm in Dror,Haouari and Chaouachi[11].These results show that the genetic algorithm is time consuming compared to the exact approach of Feremans[15].Moreover the gap between the upper bound obtained by the genetic algorithm and the optimum value increases as the size of the problem becomes larger.5The generalized traveling salesman problem The Generalized Traveling Salesman Problem,denoted by E-GTSP,consists of ﬁnding a least cost cycle passing through each cluster exactly once.The sym-metric E-GTSP was introduced by Henry-Labordere[28],Saskena[56]and Sri-vastava,Kumar,Garg and Sen[60]who proposed dynamic programming formu-lations.Theﬁrst integer linear programming formulation is due to Laporte and Nobert[40]and was later enhanced by Fischetti,Salazar and Toth[18]who in-8troduced a number of facet deﬁning valid inequalities for both the E-GTSP and the L-GTSP.In Fischetti,Salazar and Toth[19],a branch-and-cut algorithm is developed,based on polyhedral results developed in Fischetti,Salazar and Toth [18].This method is tested on instances whose edge costs satisfy the triangular inequality(for which E-GTSP and L-GTSP are equivalent).Moreover heuristics producing feasible E-GTSP solutions are provided.Noon[50]has proposed several heuristics for the GTSP.The most sophis-ticated heuristic published to date is due to Renaud and Boctor[53].It is a generalization of the heuristic proposed in Renaud,Boctor and Laporte[54]for the classical TSP.Snyder and Daskin[59]have developed a genetic algorithm which is compared to the branch-and-cut algorithm of Fischetti,Salazar and Toth[19]and to the heuristics of Noon[50]and of Renaud and Boctor[53].This genetic algorithm is slightly slower than other heuristics,but competitive with the CPU times obtained in Fischetti,Salazar and Toth[19]on small instances, and noticeably faster on the larger instances(containing up to442vertices).Approximation algorithms for the GTSP with cost function satisfying the triangle inequality are described in Slav´ık[58]and in Garg,Konjevod and Ravi [21].A non-polynomial-time approximation heuristic derived from Christoﬁdes heuristic for the TSP[7]is presented in Dror and Haouari[10];it has a worst-case ratio of2.Transformations of the GTSP instances into TSP instances are studied in Dimitrijevi´c and Saric[9],Laporte and Semet[41],Lien,Ma and Wah[44],Noon and Bean[49].According to Laporte and Semet[41],they do not provide any signiﬁcant advantage over a direct approach since the TSP resulting from the transformation is highly degenerate.The GTSP arises in several application contexts,several of which are de-scribed in Laporte,Asef-Vaziri and Sriskandarajah[38].These are encountered in post box location(Labb´e and Laporte[36])and in the design of postal deliv-ery routes(Laporte,Chapleau,Landry,and Mercure[39]).In theﬁrst problem the aim is to select a post box location in each zone of a territory in order to achieve a compromise between user convenience and mail collection costs.In the second application,collection routes must be designed through several post boxes at known locations.Asef-Vaziri,Laporte,and Sriskandarajah[3]study the problem of optimally designing a loop-shaped system for material transportation in a factory.The factory is partitioned into|K|rectilinear zones and the loop must be adjacent to at least one side of each zone,which can be formulated as a GTSP.The GTSP can also be used to model a simple case of the stochastic vehicle routing problem with recourse(Dror,Laporte and Louveaux[12])and some families of arc routing problems(Laporte[37]).In the latter application,a9symmetric arc routing problem is transformed into an equivalent vertex routing problem by replacing edges by vertices.Since the distance from edge e1to edge e2depends on the traversal direction,each edge is represented by two vertices, only one of which is used in the solution.This gives rise to a GTSP.6The generalized minimum perfect matching problemThe E-GMPMP and L-GMPMP are polynomial.Indeed,the E-GMPMP remains a classical MPMP on the shrunk graph,where c kℓ:=min{c ij:i∈V k,j∈Vℓ}for {k,ℓ}∈E S.Moreover the L-GMPMP can be reduced to the E-GMPMP.7The generalized minimum2-edge-connected network problemThe Generalized Minimum Cost2-Edge-Connected Network Problem(E-G2ECN) consists ofﬁnding a minimum cost2-edge-connected subgraph that contains ex-actly one vertex from each cluster(Figure2).Figure2:A feasible E-G2ECN solutionThis problem arises in the context of telecommunications when copper wire is replaced with high capacity opticﬁber.Because of its high capacity,this new technology allows for tree-like networks.However,this new network becomes failure-sensitive:if one edge breaks,all the network is disconnected.To avoid this situation,the network has to be reliable and must fulﬁll survivability condi-tions.Since two failures are not likely to occur simultaneously,it seems reasonable to ask for a2-connected network.10This problem is a generalization of the GMSTP.Local networks have to be interconnected by a global network;in every local network,possible locations for a gate(location where the global network and local networks can be intercon-nected)of the global network are given.This global network has to be connected, survivable and of minimum cost.The E-G2ECNP and the L-G2ECNP are studied in Huygens[29].Even when the edge costs satisfy the triangle inequality,the E-G2ECNP and the L-G2ECNP are not equivalent.These problems are N P-hard.There cannot exist a polynomial-time heuristic with bounded worst-case ratio for E-G2ECNP.In Huy-gens[29],new families of facet-deﬁning inequalities for the polytope associated with L-G2ECNP are provided and heuristic methods are described.8The generalized minimum clique problemIn the Generalized Minimum Clique Problem(GMCP)non-negative costs are associated with vertices and edges and the graph is|K|-partite complete.The GMCP consists ofﬁnding a subset of vertices containing exactly one vertex from each cluster such that the cost of the induced subgraph(the cost of the selected vertices plus the cost of the edges in the induced subgraph)is minimized(see Figure3).Figure3:A feasible GMSCP solutionThe GMCP appears in the formulation of particular Frequency Assignment Problems(FAP)(see Koster[34]).Assume that“...we have to assign a frequency to each transceiver in a mobile telephone network,a vertex corresponds to a transceiver.The domain of a vertex is the set of frequencies that can be assigned to that transceiver.An edge indicates that communication from one transceiver may interfere with communication from the other transceiver.The penalty of an11edge reﬂects the priority with which the interference should be avoided,whereas the penalty of a vertex can be seen as the level of preference for the frequen-cies.”(Koster,Van Hoesel and Kolen[35]).The GMCP can also be used to model the conformations occurring in pro-teins(see Althaus,Kohlbacher,Lenhof and M¨u ller[2]).These conformations can be adequately described by a rather small set of so-called rotamers for each amino-acid.The problem of the prediction of protein complex from the structures of its single components can then be reduced to the search of the set of rotamers, one for each side chain of the protein,with minimum energy.This problem is called the Global Minimum Energy Conformation(GMEC).The GMEC can be formulated as follows.Each residue side chain of the protein can take a number of possible rotameric states.To each side chain is associated a cluster.The vertices of this cluster represent the possible rotameric states for this chain.The weight on the vertices is the energy associated with the chain in this rotameric state. The weight on the edges is the energy coming from the combination of rotameric states for diﬀerent side chains.The GMCP is N P-hard(Koster,Van Hoesel and Kolen[35]).Results of polyhedral study for the GCP were embedded in a cutting plane approach by these authors to solve diﬃcult instances of frequency assignment problems. The structure of the graph in the frequency assignment application is exploited using tree decomposition approach.This method gives good lower bounds for diﬃcult instances.Local search algorithms to solve FAP are also investigated. Two techniques are presented in Althaus,Kohlbacher,Lenhof and M¨u ller[2]to solve the GMEC:a“multi-greedy”heuristic and a branch-and-cut algorithm. Both methods are able to predict the correct complex structure on the instances tested.9The generalized Steiner tree problemThe standard generalization of the STP is the T-Generalized Steiner Tree Prob-lem in its“at least”version(L-GSTP).Let T⊆V be partitioned into clusters. The L-GSTP consists ofﬁnding a minimum cost tree of G containing at least one vertex from each cluster.This problem is also known as the Group Steiner Tree Problem or the Class Steiner Tree Problem.Figure4depicts a feasible L-GSTP solution.The L-GSTP is a generalization of the L-GMSTP since the L-GSTP deﬁned on a family of clusters describing a partition of V is a L-GMSTP.This problem was introduced by Reich and Widmayer[52].The L-GSTP arises in wire-routing with multi-port terminals in physical Very Large Scale Integration(VLSI)design.The traditional model assuming sin-12Figure4:A feasible L-GSTP solutiongle ports for each of the terminals to be connected in a net of minimum length is a case of the classical STP.When the terminal is a collection of diﬀerent pos-sible ports,so that the net can be connected to any one of them,we have an L-GSTP:each terminal is a collection of ports and we seek a minimum length net containing at least one port from each terminal group.The multiple port locations for a single terminal may also model diﬀerent choices of placing a single port by rotating or mirroring the module containing the port in the placement (see Garg,Konjevod and Ravi[21]).More detailed applications of the L-GSTP in VLSI design can be found in Reich and Widmayer[52].The L-GSTP is N P-hard because it is a generalization of an N P-hard problem.When there are no Steiner vertices,the L-GSTP remains N P-hard even if G is a tree(see Section4).This is a major diﬀerence from the classical STP(if we assume that either there is no Steiner vertices or that G is a tree,the complexity of STP becomes polynomial).Ihler,Reich and Widmayer[31]show that the graph G can be transformed(in linear time)into a graph G′(without clusters)such that an optimal Steiner tree on G′can be transformed back into an optimal generalized Steiner tree in G.Therefore,any algorithm for the STP yields an algorithm for the L-GSTP.Even if there exist several contributions on polyhedral aspects(see among others Goemans[24],Goemans and Myung[23],Chopra and Rao[5],[6])and exact methods(see for instance Koch and Martin[33])for the classical problem, only a few are known,as far as we are aware,for the L-GSTP.Polyhedral aspects are studied in Salazar[55]and a lower bounding procedure is described in Gillard and Yang[22].13A number of heuristics for the L-GSTP have been proposed.Early heuris-tics for the L-GSTP are developed in Ihler[30]with an approximation ratio of |K|−1.Two polynomial-time heuristics are tested on instances up to250vertices in Ihler,Reich and Widmayer[31],while a randomized algorithm with polylog-arithmic approximation guarantee is provided in Garg,Konjevod,Ravi[21].A series of polynomial-time heuristics are described in Helvig,Robins,Zelikovsky [27]with worst-case ratio of O(|K|ǫ)forǫ>0.These are proved to empirically outperform one of the heuristic developed in Ihler,Reich and Widmayer[31].In the Vertex Weighted Steiner Tree Problem(VSTP)introduced by Segev [57],weights are associated with the vertices in V.These weights can be negative, in which case they represent proﬁt gained by selecting the vertex.The problem consists ofﬁnding a minimum cost Steiner tree(the sum of the weights of the selected vertices plus the sum of the weights of the selected edges).This problem is a special case of the Directed Steiner Tree Problem(DSP)(see Segev[57]). Given a directed graph G=(V,A)with arc weights,aﬁxed vertex and a subset T⊆V,the DSP requires the identiﬁcation of a minimum weighted directed tree rooted at theﬁxed vertex and spanning T.The VSTP has been extensively studied(see Duin and Volgenant[13],Gorres[25],Goemans and Myung[23], Klein and Ravi[32]).As far as we know,no Generalized Vertex Weighted Steiner Tree Problem has been addressed.An even more general problem would be the Vertex Weighted Directed Steiner Tree Problem.10The generalized shortest path problemLi,Tsao and Ulular[43]describe an S-generalization of the SPP in its“at most”version(M-GSPP).Let o and d be two vertices of G and assume that V\{o,d}is partitioned into clusters.The M-GSPP consists of determining a shortest path from o to d that contains at most one vertex from each cluster.Note that the T-generalization is of no interest since it reduces to computing the shortest paths between all the pairs of vertices belonging to the two diﬀerent clusters.In the problem considered by Li,Tsao and Ulular[43],each vertex is as-signed a non-negative weight.The problem consists ofﬁnding a minimum cost path from o to d such that the total vertex weight on the path in each traversed cluster does not exceed a non-negative integerℓ(see Figure5).This problem with ℓ=1and vertex weights equal to one for each vertex coincides with the M-GSPP.The problem arises in optimizing the layout of private networks embedded in a larger telecommunication network.A vertex in V\{o,d}represents a digital cross connect center(DCS)that treats the information and insures the transmis-sion.A cluster corresponds to a collection of DCS located at the same location14。

IDL常用关键字

一、IDL常用关键字1、FID文件ID（FID）是一个长整型的标量，FID 为ENVI 的程序员提供了一个命名变量，可以被数个ENVI 程序所使用，来打开或选择文件。

2、R_FID 和和M_FIDENVI 处理程序所产生的影像结果也包括一个R_FID，或者称为返回FID 关键字。

如果结果是存在内存中的，设置R_FID 关键字是访问该数据的唯一方法。

在掩模处理程序还包括一个M_FID，或者称为掩模FID 关键字，用于确定用作掩模波段的文件3、DIMSDIMS 关键字是一个5 个元素长整型数组。

它定义了处理数据的空间子集。

当需要确定FID 的时候，用户必须同时使用DIMS 关键字确定该文件的空间子集。

DIMS[0]：用于存储指向一个打开的ROI 区域的指针，仅在ROI 被定义的时候使用，其它时候设为-1DIMS[1]：采样的起始位置（一个基于0 的IDL 数组下标）DIMS[2]：采样的终止位置DIMS[3]：行的起始位置DIMS[4]：行的结束位置4、POSPOS 关键字定义了用于处理的波段位置。

POS 关键字是一个变长的长整型数组。

因为ENVI 处理的文件可能具有多个波段，而使用POS 矢量来确定用于处理的波谱子集。

二、文件管理函数：1、ENVI_PICKFILEENVI_PICKFILE 函数产生一个提示用户选择文件的对话框。

该函数产生的界面和使用ENVI 主菜单选择File->Open Image File 一样的界面。

该函数并不真正的打开文件，它只是以字符串的形式返回用户所选择的全路径文件名。

2、ENVI_SELECTENVI_SELECT 产生对话框提示用户从ENVI 中已经打开的文件中选择一个文件。

该函数产生ENVI 标准的文件选择对话框，其中包括空间和波谱子区裁剪按钮，以及掩模波段选取按钮。

3、ENVI_OPEN_FILE该函数返回一个文件的FID，它是打开ENVI 文件的最直接和简单的方法。

初始穿透异常的解决方法

初始穿透异常的解决方法
针对初始穿透异常问题，可以采取以下方法解决：
1. 手动调整单元节点：在进行模型网格划分和设置零件厚度时必须确认是否存在干涉，即必须考虑壳单元的接触厚度。

如果发生穿透，可以从计算出的message或d3hsp文件中对关键字“initial penetrations”进行搜索，找到相关单元，然后调整单元节点，消除初始穿透。

在一些专门的前处理软件中，例如ANSA、HYPERMESH、SpaceClaim在提交计算前对模型进行穿透检查，可以查出初始穿透的单元，然后进行节点移动，消除穿透。

2. 减小接触厚度：对于比较小的初始穿透问题，可以通过减小接触厚度来解决，对应于CONTACT关键字中的控制参数SFST和SFMT。

但由于缩小了接触厚度，为保持接触力的稳定，应相应增大罚函数刚度（控制参数SFS和SFM）。

该方法只对很小的初始穿透效果好，对于大的初始穿透，可能会导致错误的结果。

3. 增加相关控制参数：LSTC公司在LS-DYNA960中增加了相关控制参数来处理该问题。

请注意，不同的情况可能需要不同的解决方法，建议咨询专业人士获取更准确的信息。

B21 7050indC English

11.2.ENDURANCE TO CURRENT CYCLES24 APPENDIX1TEST ASSEMBLIES25 APPENDIX2MECHANICAL STRENGTH26 APPENDIX3SCHEMATIC DIAGRAMS FOR VIBRATION TEST29 APPENDIX4THERMAL SHOCK CYCLES31 APPENDIX5CYCLES IN VARIABLE ATMOSPHERE32 APPENDIX6PROGRAMME OF APPROVAL TESTS33 APPENDIX7HOUSING TECHNICAL SHEET36 APPENDIX8CONTACT TECHNICAL SHEET37 12.RECORDS AND REFERENCE DOCUMENTS3812.1.RECORDS3812.2.REFERENCE DOCUMENTS3812.3.EQUIVALENT TO:3912.4.CONFORMS TO:3912.5.KEY WORDS39 1.OBJECT AND FIELD OF APPLICATIONThe purpose of this norme is to define the technical specifications and general test methods relating to connectors.If a specific Cahier des Charges exists,it will be the official document which must be referred to together with this norme.This document does not apply to battery connectors nor to high voltage connectors which are both the subject of particular specifications.2.EXPRESSION ON DOCUMENTSApplication of the requirements of this norme must be indicated on documents in the following form:norme B217050with the code defined below.•Connector.•Temperature class(see§Temperature class).•Vibration class(see§Vibration class).•Sealing class(see§Sealing class).•The reference number and the suffix of this norme.Example:Connector T4V1E0B217050(suffix)designates a connector with a temperature class4, vibration class1,sealing class0defined by this norme.Furthermore,drawings must carry the following details:A-FUNCTIONAL DRAWINGNote:In general,the supplier’s official drawing is used as the functional drawing.B-SUPPLIER’S DRAWING(Structure of documents)in French or bilingual(French+…)B1-Definition drawing of a contactThe definition drawing of a contact shall include,a minimum of sheets1&2(A3,A2or A1format)with an identical PSA title block on all sheets.The drawing for each crimping range of operation must be submitted by the supplier(see§3-C).•Sheet1:product definition containing:•the functional dimensions,•the materials used,•the maximum environmental temperatures•the coatings used,•the specific coating area and the points for measuring thicknesses,•the conformity in accordance with norme B217050and the CDC(Cahier Des Charges)of the contact,•the supplier’s reference for single wire seals(or on sheet2),•the suppliers’reference for the contact,•the marking of a minimum identification character for the material and/or the coating,•the modification table with traceability of modifications.•Sheet2:definition of crimping specifications containing:•the conformity of packaging(see E73.03.150G),•the spacing for contacts supplied in strips,•the pilot position in relation to the contact,•the dimensioned drawing for the anvil and the punch,•the height and width dimensions to be checked on the contact after crimping(relaxation after crimping must be specified if taken into account).Note:These dimensions are to be specified for each section of conductor to be crimped using the contact range(including2conductors).•the stripping length of conductor,•the positioning of the conductor in the conductor crimps,•the positioning of the seal on the conductor,•the positioning of the seal in the insulation crimps,•the maximum permitted angular deformation(in3directions)in the crimping area in relation to the front base of contact,•the functional dimensions after deformation in the double locking area of the contact,•Sheet3:•drawing for the suitability to fitting and to blending of the contact specifying the recommended functional dimensions for the primary locking and the double locking.B2-Definition drawings of a connector blade/clip housingThe definition of a housing shall include a minimum of3drawings(A3,A2or A1format)•Drawing1:definition of the cavity containing:•the functional dimensions,•the recommended material and the minimum modulus of elasticity,•the modification table with traceability of modifications.•Drawing2:definition of the interface containing:•the functional dimensions,•the numbering of connector blades,•the grading*of connector blades in relation to norme B125210,•the length of the blade including tolerance shall be specified•the mechanical strength*of connector blades in relation to norme B125210.*Indicate“in conformity with norme B125210except for...”quoting only the differences.•the connector blades fitting dimensions defined from clearly identified reference surfaces,•the grading for the mechanical foolproofing device/colour identification defined from clearly identified reference surfaces,•the grading for the sheet metal cut out with the size and orientation of permitted burrs,permitted cut out radii,the minimum flat area,•the area to remain free(hatched)for the connection of the counter-part(with tool included),•the volume after connection,•the recommended material,•the reference of the cahier des charges on connections,•the modification table.•Drawing3:definition of the supplied product containing:•the conformity of the packaging(see E73.03.150G),•the functional dimensions.Note:Do not show dimensions already quoted on drawings1and2.Indicate:“cavity in accordance with STE PSA96.......99”.“cavity position in accordance with STE PSA96......99”•the cavities numbering,•the markings with their location,according to norme B201315•the volume of the connector from a perspective view,•the supplier’s reference for the connectors recommendation file,•the supplier’s reference for the various housing components,(Parts list of the constituents)•the supplier’s reference for plugs,or blanking plugs,•the supplier’s reference for contacts or reference to the PSA table plan if applicable•the materials,•the modification table with traceability of modifications•the product mass.Note:The functional dimensions are at least those shown in the re-fitting file.It is recommended to number these dimensions with the same numbers as those shown in the re-fitting file. The reference faces must clearly be quoted on all drawings and in correlation with each other.Modifications must be clearly shown in the modification table.The drawing must not carry any cross references to PSA documents which are not officialised.One detail must only be stated in one place,other documents must refer to it(eg.:see§X in CDC BXX XXXX).C-RECOMMENDATION FILE FOR CONNECTORS(in French and in English)The recommendation file for connectors(A4format)must contain all the required information for the implementation of the supplied product.The file consists of:•the packaging(see E73.03.150G),•storage and handling,•the supplier’s references for the components,•the supplier’s drawing number for crimping specifications,•the tools for unlocking the double locking system of contacts*,•the tools for the removal of contacts*,*The tools may be defined by a reference and/or a dimensioned drawing.•the tools for fitting onto the vehicle,•the method for inserting contacts,•the method for the assembly of supplied components,•the method for the disassembly of supplied components,•the method for re-work(specifying the components to be systematically replaced or not),•the recommendations for guaranteeing and checking the presence of seals,plugs and blanking plugs •the areas on the housing which MUST NOT be pressed on,•the bearing faces recommended for activating the double locking,•the grading for the electrical test peaks,and the compression loads for test peaks•a test counter-part principle,•the contact conformators for sealing,by adding material•the loads NOT SPECIFIED on the CDC which would be required for implementation.•a paragraph titled“FITTING”regrouping the methods for connection,disconnection and inspection to be performed on the assembly line of the vehicleNote:This file must be clear and legible.Use simple sketches rather than phrases.This file must not contain more than10pages approximately.A framework,to be used preferentially,exists in the design rules for connectors.D-TECHNICAL FILEA complement to sections A,B,&C:•documents for re-fitting supplied by the supplier,•product FMECA,•functional analysis•development plan including any validations,•Cahier des Charges,•interactive questionnaire,•validation test resultsRemark:The supplier’s drawing may contain particular specifications following the supplier’s request and approved by the appropriate departments.3.GENERAL REQUIREMENTSThese requirements are those of cahier des charges B200110with the exception of the paragraphs below which are expanded as follows:C-APPROVAL OF SUPPLIES•To complement the approval tests carried out by the supplier,a validation report must be supplied as well as20samples,unless otherwise specified on the CDC and in the interactive questionnaire.•Drawing of the crimping range of operation(see§2-B).•A set of tools for fitting and removal.•The connectors are tested in the conditions of appendix6.•Technical sheets in accordance with appendices7and8must be submitted with the connectors.•The connectors must not require maintenance.E-MARKINGThe suppliers name or trademark,the mould and its cavities as well as the reference of the month of manufacture,in accordance with B118030,must be inscribed in a legible and indelible manner on the connectors.Location marking for cavities and housings must comply with the design rules for connectors.For the recycling of plastic and rubber parts,the marking must be in conformity with norme B201315and B20 1415.F–SUPPLIERS QUALITYAcceptance of initial samples:According to norme Q610300“Supplier quality assurance product acceptance”and Q610310“Acceptance of initial samples for connectors”.4.TERMINOLOGY AND DEFINITIONTerm Symbol DefinitionCavity Receptacle for receiving one contact only in a housing or module. Housing/skirt Group of electrical connections for receiving one or morecontacts/modules in different cavities/housing.Plug Part designed to seal a cavity,which is not used,in a housing using singlewire sealsConnector(socket)Mechanical female structure to be connected to one or more conductors.Its function is to provide the electrical continuity through connection to ablade(pin).Conductor Core and insulating cover assemblyConnector Group of electrical connections which connect one or more conductorsbetween them or to an equipmentContact Connecting component providing the passage of an electric currentContact in wrong position Contact allowing the electrical connection to be established when the contact is coupled even though it is not correctly locked in its cavityInsulation displacement or self-stripping contact DI Technique providing the electrical connection between contact/conductor without prior stripping of the connector.Colour Visual means for rapid identification of compatible parts by colouridentification associated to mechanical foolproofing.Mechanical inhibitor Device which prevents the mechanical assembly of two incompatible parts associated to colour identificationDouble locking of connectors CPA Inspection device allowing the assembly of the connector to be checked.Not recommended by PSA.Double locking of contacts/modules DL Device for detecting whether the primary locking is correctly made.To fulfil this function,the device calls for a secondary lock(V.S.).If the primary locking of the contact/module is not made,the doublelocking must-either reset the contact/module in locked position,-or prevent the connection of the housing to the counter-part.Aligning effect Inertia effect by which the connector can be coupled but does not allowelectrical contact to be made unless mechanical locking of the housingagainst its counter part has been achieved.Kojiri effect Effect which prevents the pins of the base not to twist whatever theposition of the housing connector as it approaches the base.Base Group of electrical connections comprising of blades(pins)integral withthe body of the equipmentCalliper Device to aid the coupling alignment of connectors by the sliding of lugsinto a slotBinding Device providing a mechanical link(wire/contact)separate from theelectrical linkRange Conductor section range permitted for the connection to a contact Edging strip Plastic excessive thickness produced on the side of a housing in order tolimit the play of a coupled connector such as to provide better vibrationcharacteristicsGel joint A sealing joint to be positioned within a housing in order to ensure that allconductors and the housing are sealed;each contact passing through aself-sealing gel.Grommet A sealing joint positioned within the housing and providing sealingbetween each connector and the housing.Single wire seal Sealing joint crimped to the rear of the contact and providing sealingbetween one contact only and the housing.Connector blade (pin)Mechanical male structure to be connected to one or more conductors.Its function is to provide the electrical continuity through connection to a clip (socket).Lever Device to aid with the coupling of connectors by rotation around a leverarm axis.Housing Receptacle for receiving one module only in a skirtModule Contact support to be inserted into a skirt housing to form a connector. Blanking plug Plastic part designed to seal an unused cavity within a housing using agrommetPolarisation Device prohibiting the fitting of contacts,modules or connectors in theircavities,skirts or counter-parts after rotation through any of their anglesaround the plug-in axis.Housing connector PC Housing consisting of cavities,receiving connectors to be connected to ahousing blade or a base located on an equipmentHousing blade PL Housing consisting of cavities for receiving connector blades to beconnected to a housing connector.Locking spring Metal spring which completes the mechanical locking of connectors byclipping into lugs.Crimping Technique providing a permanent electrical connection betweencontact/conductor by controlled deformation of the stripped conductor intothe crimped terminal of a contact.Primary locking Device for the retention of an element in relation to another.It applies tocontact,module and housing.5.CLASSIFICATION OF ENVIRONMENTAL CONDITIONSAccording to its location on the vehicle,connectors may be stressed by physical characteristics(temperature, vibration,...)which are classified as follows.5.1.TEMPERATURE CLASSClass Temperature ofenvironmentt(°C)Environment Typical application*Testtemperature(°C)±2°CT1-40to85Exposed to moderateheat sources.Facia panel,instrumentcluster,...100T2-40to100Exposed to considerableheat sources by radiationUnder cover125T3-40to125Highly exposed toconsiderable heat sourcesby radiation In the vicinity of theengine150T4-40to150Highly exposed toconsiderable heat sourcesby radiation andconduction In the vicinity of theexhaust.Engine oil circuit175*The applications stated are given as an example.This list is not exhaustiveNote:The temperature values are in agreement with the international norme ISO/DIS6722.These classes of temperature are to be used instead of the temperature classes of electrical and electronic equipments stated in norme B217130and the following table correspondence must be applied:Class B217050T1T2T3T4Class B217130C1&C2C3C4&C5C6and above5.2.VIBRATION CLASSClass Connector position Reference normeV1Equipment on body B217120V2Equipment on engine(mass less than0,5kg)B217120V3Equipment connected to the engine B2171205.3.LOW FREQUENCY STRESS CLASSClass Connector position Reference normeS1Under the seat D115501S2Inside the door B2511405.4.SEALING CLASSClass Level of requirement Reference norme Action to be taken 0Not sealed1Sealed to water spray B1429002Sealed to immersion B142900Validation according to group5A Pressure cleaning B142900/D155319Specify the duration of therinse and the requirementsafter testingB Sealed to dust B217130/NF EN60529Note:The alphabetical classes can be used concurrently with the numeric classes.See the specific CDC for the unit.5.5.HYGROMETRYParts must be able to meet variations in hygrometry from0to100%.5.6.CRIMPING RANGEThe conductors crimping ranges must be no larger than those defined in the following table and must,in all cases,comply with“connector crimping specification”:Range Permitted section(mm²)1st0,22≤S<0,5or0,35≤S≤0,52nd0,5≤S<1or0,5<S≤13rd1≤S<2or1<S≤24th2≤S≤35th3≤S≤56th5≤S≤77th7≤S≤108th10≤S≤165.7.INSULATOR DISPLACEMENT RANGEConnectors with insulator displacement must only allow one section of conductor for each range of contact.6.GENERAL TEST CONDITIONSUnless otherwise specified,the tests are carried out in the following conditions:•Temperature:23°C±5°C.•Relative humidity:45to75%.•Atmospheric pressure:860to1060hPa.•Supply voltage:13,5±0,1V.The supply voltage is from a stabilised supply of internal resistance less than0,01Ω.It must not include a superimposed wave voltage greater than0,3V peak to peak.7.TECHNICAL CHARACTERISTICS AND DESIGNConnectors must be developed in conformity with“connector design rules”7.1.PROHIBITED MATERIALSIn conformity with norme B200250,the following materials are prohibited when designing connectors:•Cadmium and derived substances•Mercury and derived substances•Lead•Hexavalent chromium•Halogen•Carbon black,in products to be used for sealing.7.2.POLARISATION DEVICEIrrespective of the assembly(housing/base,housing/housing,module/skirt,contact/cavity),the polarisation device must be designed so as to prohibit incorrect fitting.The polarisation device must fulfil its function before an electrical connection may be established.7.3.FOOLPROOFING DEVICEIrrespective of the assembly(housing/base,housing/housing,module/skirt),the foolproofing device consists ofa mechanical inhibitor combined with a colour identification.7.3.1.MECHANICAL INHIBITORThe mechanical inhibitor must fulfil its function before an electrical connection may be established.7.2.2.COLOUR IDENTIFICATIONThe colour identification must only use colours stated in the following table:Colour Abbreviatedcode Current referenceNFX08-002Typical code ToleranceWhite BA A665-A670A665MAX.A670 Blue BE A570-A571A570MAX.A571 Grey GR A624-A625A624MAX.A625 Yellow JN A310–A330A330MIN A310 Brown MR A002-A020A002MAX.A020 Black NR A600-A603A600MAX.A603 Orange OR A110-A130A110MAX.A130 Pink RS A870-A880A870MAX.A880Red RG A801A805A810A805MIN.A801MAX.A810Green VE A450A455A460A455MIN.A450MAX.A460Violet VI A730A790A950A790MIN.A730MAX.A950The electrical and mechanical characteristics of connectors must remain in conformity with the requirements of the particular specification irrespective of the colouring used.Note:Violet is only used for connectors intended for After-Sales(2nd fitting)which must be able to accept all foolproofing devices.7.4.LOCKINGContact/Cavity LockingAll housings(apart from those with insulation displacement which have pre-loaded contacts)must have a primary locking system for contacts as well as a secondary locking device which allows any contact badly fitted in its cavity to be detected and preventing,in this case,fitting the connector.The DL must be independent from the housing on deliveryModule/Housing lockingThe locking can only be achieved if the contacts are correctly locked in the module.Housing/Counter-Part lockingIf locking has not taken place once the operator ceases to apply the positioning effort:•no electrical contact is allowed,•the housings must not remain assembled.7.5.HOUSINGPre-guiding of the housing connectors on the housing blades is necessary before electrical contact is established between the connector and the bladeOn blade housings and bases,a mechanical protection of the blades is to be provided in order to prevent damage during the connection of their counter-parts if there is a risk that the condition of the blades will deteriorate during the connection.Blade housings used in inter-connection must incorporate a device enabling their attachment to a standard PSA clip.If the connecting and disconnecting load of connectors is greater than60N,an aid device to the mechanical connection is to be provided.If the load is less than60N the connector must include an aligning effect.7.6.COATING OF CONTACTSUnless otherwise specified,the coatings of the contact elements involved with the passage of the current must be in conformity with norme B125220.7.7.SEALING DEVICESThe position of plugs within cavities of the housing must be clearly defined.8.ELECTRICAL CHARACTERISTICS8.1.MEASUREMENT OF THE CONTACT RESISTANCE8.1.1.METHOD FOR mVMeasurement of the contact resistance is carried out with the test assemblies defined in appendix1.The linear resistance of connectors must be subtracted to obtain the resistance of the contact.The voltage in open circuit must not exceed20mV DC,in order to avoid the break of possible insulating films on the contacts.The current in the contacts must be100mA maximum.For low current connectors,the current must be specified in the definition document of the part(Norme or drawing).Note:The measurement must be carried out for both current directions,if specified by the CDC. Requirement:The resistance of each contact must be in conformity with the values defined in the following table.Type of contactmm Max.initial RcMΩ∆Rc maxmΩ0,63641,5442,8335and6,3522≥811 Note:The initial contact resistance is the first measurement carried out on a sample.8.1.2.NOMINAL CURRENT METHODThe measurement is carried out under the nominal current defined in§“Contact derating curve”after thermal stabilisation.The test voltage must be between1V and16V.Note:The measurement must be carried out for both current direction if specified by the CDC. Requirement:Identical to§Method for mV.8.2.INSULATION RESISTANCEThe measurement of the insulation resistance is carried out when a stable reading is obtained.If the conditions of stability are not fulfilled,the insulation resistance is measured60s±5s after applying the voltage.The insulation resistance is measured under a continuous voltage of500V±15V between each contact subjected to the test and other interconnected contacts with the connector housing or the fixing plate.The measurement is carried out with coupled connectors.Requirement:The value of the insulation resistance must be greater than100MΩ.8.3.DIELECTRIC RIGIDITYAn effective alternate voltage of1000V±50V,50Hz is applied for60s±5s between each contact subjected to the test and other interconnected contacts with the housing or the fixing plate.The measurement is carried out with coupled connectors.Requirement:No discharge,crackling,shorting,incipient arcing or arcing must occur during the test.8.4.RESISTANCE TO CRIMPINGCrimping of the contact must conform to the electrical characteristics defined in the connector crimping specification STE9634115099.Crimping of the contact of vibration classes V2,V3,S1or S2must conform to norme D115501Connections-Dynamic low frequency vibratory stress tests of crimpings.8.5.CONTACT DERATING CURVEThe derating curve of a contact represents the maximal current allowed as a function of the ambient temperature.It is based on one contact alone in its housing.The measurement of this curve is completed under test conditions defined by norme NF C93-400,test5b. 9.MECHANICAL CHARACTERISTICSAll tests on the tensile test machine are to be completed at a constant speed between25and50mm/minute.PONENTSCrimping of contacts must conform to the mechanical characteristics defined in the connector crimping specification STE9634115099.The conductors used must conform to the generic technical specification for classic electrical conductors STE 9641879499.9.1.1.TENSILE STRENGTH OF THE CONDUCTOR/CONTACT CONNECTIONThe tested products are described below:•crimping:one contact connected to one or more conductors.Note:In the case where two conductors are on the same contact,the check must be carried out on each conductor(provide as many samples as there are conductors).•insulator displacement:one contact,fitted to its cavity,connected to one conductor only with and without a retaining device.9.1.1.1.Axial tensile testThe tested product,fixed between the Jaw of a tensile test machine,is subjected to a tensile load applied to the conductor/contact connecting axis.Test A:The jaw of the tensile test machine travels until the conductor is torn off the contact. Requirement:The value of the tearing load must be greater than the value defined in appendix2.Test B:The Jaw of the tensile test machine travels until the value defined in appendix2is reached. The load is maintained at this value for10seconds.Requirement:During and at the end of the test,there must be no mechanical damage(tearing or slipping of the wire in the contact).9.1.1.2.Perpendicular tensile testThis test is carried out in the same conditions as in§Axial tensile test except that the load is applied in any direction perpendicular to the conductor/contact connecting axis.The test is carried out:contact fitted into the cavity.Requirement:Identical to§Axial tensile test.9.1.2.MEASUREMENT OF INSERTION LOADS9.1.2.1.Contact/Module or Contact/HousingThe double locking device passive then active.The contact is connected to a conductor(min.and max.crimping range of operations)in production wiring conditions,the module/housing is fixed to a load transducer and the contact is inserted automatically. Requirement:The insertion load must not be greater than(DL passive)or less than(DL active)to the values defined in Appendix2.Note:For grommet connectors,the manufacturer must define a complete typical configuration such as to satisfy the requirements independently of the order of fitting.To reproduce production assembly conditions,the insertion is completed manually.Requirement:Good guidance of the contact within the cavity,without intermediary stop.No sensation of double click.No buckling of the thread.No crossing of the front face of the housing.9.1.2.2.Module/HousingDouble locking device passive then active.The module is fitted with its contacts.The wire orientation must observe the fitting recommendation specifications in order to reproduce production assembly conditions,the housing is fixed to a load transducer and the module is inserted automatically.Requirement:The insertion load must not be greater than(DL passive)or less than(DL active)the values defined in Appendix2.To reproduce the production assembly conditions,the insertion is completed manually.Requirement:Good guidance of the module within the housing.No intermediary stop.No sensation of double click.No risk of the thread being caught between the housing and skirt.9.1.2.3.Double locking/Housing•Resistance of the DL in the delivery position(If different to pre-fitted)The Jaw of the tensile test machine move until the DL changes positionRequirement:The load must be greater than the value stated in Appendix2.Load required to pass from the pre-fitted position to the locking position.•All contacts and or modules correctly positioned.The housing equipped with all its contacts/modules is fixed to a load transducer and the double locking device is automatically set.Requirement:Whatever the point of activation,the load required to change from the pre-fitted position into the locked position must be between the values defined in Appendix2,unless otherwise specifiedTo reproduce the production assembly conditions,the DL is inserted manually.Requirement:All intermediary positions for the DL must be easily identified and must prohibit coupling of the connectors.No contact attack.No partial locking of the DL.•One or more badly positioned contacts or modules(Whatever the cavity)The housing equipped with all its contacts/modules(one or more being badly positioned)is fixed on a load transducer and the double locking device is automatically setRequirement:Whatever the point of application of the load,this must be greater than the value defined in Appendix2,or the DL must realign the badly positioned contacts/modulesTo reproduce the production assembly conditions,the DL is inserted manually.Requirement:No possibility of setting the DL or repositioning the contacts by the DL.9.1.2.4.Plug/Cavity or Blanking plug/Grommet.In cases of sealed connectors,the plug(or blanking plug)shall be inserted automatically at a constant speed. Requirement:The effort required to insert it must not exceed the values defined in Appendix2.9.1.2.5.Cover/Housing.The housing is equipped with its contacts.The wire orientation must be in line with the fitting recommendation document.In order to reproduce the production assembly conditions,the housing is fixed on a load transducer,and the cover is placed automatically at constant speedRequirement:The load required to place the cover in place must not exceed the values defined in Appendix2.9.1.3.MEASUREMENT OF RETENTION LOADSThe purpose of these tests is to check the ability of the retention system of a connector components to withstand mechanical loads which may occur during the various situations in the life of the product.。

saml2.0原理 -回复

saml2.0原理-回复SAML 2.0 (Security Assertion Markup Language) 是一种用于在认证和授权之间传递安全性信息的开放标准。

它被广泛应用于企业环境中的单点登录和身份提供者之间的集成。

本文将逐步解释SAML 2.0的原理，包括认证流程、组成角色和消息交换过程。

一、SAML 2.0概述SAML 2.0 是一种基于XML 的标准，用于在不同的安全域之间传递身份认证和授权数据。

它定义了三个主要角色：身份提供者（Identity Provider，简称IdP）、服务提供者（Service Provider，简称SP）和用户。

SAML 2.0的认证流程基于以下几个主要步骤：请求、响应和断言。

二、认证流程1. 请求用户在访问服务提供者的应用程序时，被重定向到身份提供者的登录页面。

2. 登录用户在身份提供者的登录页面上输入其凭据并进行验证。

3. 断言生成一旦用户通过身份验证，身份提供者将生成一个断言（Assertion），其中包含用户的身份信息和授权数据。

断言可以是基于用户名密码的验证或其他方式，如数字证书或生物特征等。

4. 响应身份提供者将断言返回给服务提供者。

这一步通常是通过将断言作为HTTP POST请求的一部分发送给服务提供者来实现。

5. 服务提供者处理服务提供者通过验证断言来验证用户的身份和授权。

如果断言有效，服务提供者将用户重定向到受保护的资源或提供相应的授权。

三、组成角色和功能1. 身份提供者（IdP）身份提供者是负责认证和生成断言的实体。

它验证用户的身份，并根据授权策略生成断言。

身份提供者通常与企业的用户存储系统集成，如LDAP 或Active Directory等。

它还负责维护用户的会话状态并处理请求。

2. 服务提供者（SP）服务提供者是提供资源或服务的实体。

它接受来自身份提供者的断言，并根据断言验证用户的身份和授权。

服务提供者通常提供基于角色的访问控制和权限管理。

Escaping Nash Inflation

ESCAPING NASH INFLATIONIN-KOO CHO,NOAH WILLIAMS,AND THOMAS J.SARGENTA BSTRACT.Mean dynamics describe the convergence to self-conﬁrming equilibria of self-referential systems under discounted least squares learning.Escape dynamics recurrentlypropel away from a self-conﬁrming equilibrium.In a model with a unique self-conﬁrmingequilibrium,the escape dynamics make the government discover too strong a version ofthe natural rate hypothesis.The escape route dynamics cause recurrent outcomes close tothe Ramsey(commitment)inﬂation rate in a model with an adaptive government.Key Words:Self-conﬁrming equilibrium,mean dynamics,escape route,large deviation,natural rate of unemployment,adaptation,experimenta-tion trap.‘If an unlikely event occurs,it is very likely to occur in the most likely way.’Michael Harrison1.I NTRODUCTIONBuilding on work by Sims(1988)and Chung(1990),Sargent(1999)showed how a government adaptivelyﬁtting an approximating Phillips curve model recurrently sets inﬂation near the optimal time-inconsistent ouctome,although later inﬂation creeps back to the time-consistent suboptimal outcome of Kydland and Prescott(1977).The good outcomes emerge when the government temporarily learns the natural rate hypothe-sis.The temporary escapes from the time-consistent outcome symptomize a remarkable type of escape dynamics that promote experimentation and that are induced by unusual shock patterns that interact with the government’s adaptive algorithm and its imperfect model.The escapes lead to dramatic changes in the government’s inﬂation policy as it temporarily overcomes its inﬂationary bias.Some simulated time paths of inﬂation for different speciﬁcations of the model are shown in Figure1.Inﬂation starts and remains near the high time-consistent value for a while,is rapidly cut to zero,but then gradually2IN-KOO CHO,NOAH WILLIAMS,AND THOMAS J.SARGENTF IGURE ofthe model.approaches the time-consistent high value again.This paper explains the dynamic forces that drive these outcomes.Escape dynamics from self-conﬁrming equilibria can occur in a variety of models with large agents who use adaptive algorithms to estimate approximating models.1For con-creteness,this paper focuses on the Phillips curve model studied by Sargent(1999).The model has the following features:(1)the monetary authority controls the inﬂation rate, apart from a random disturbance;(2)the true data generating mechanism embodies a version of the natural rate hypothesis in an expectational Phillips curve;(3)as in Kydland and Prescott(1977),a purposeful government dislikes inﬂation and unemployment and a private sector forecasts inﬂation optimally;but(4)the monetary policy makers don’t know the true data generating mechanism and instead use a goodﬁtting approximating model.The fundamentals in the economy areﬁxed,including the true data generating mechanism,preferences,and agents’methods for constructing behavior rules.Changes in the government’s beliefs about the Phillips curve,and how it approximates the natural rate hypothesis,drive the inﬂation rate.Inspired by econometric work about approximat-ing models by Sims(1972)and White(1982),we endow the monetary authority,not with the correct model,but with an approximating model that it nevertheless estimates with good econometric procedures.We use the concept of a self-conﬁrming equilibrium,a natural equilibrium concept for behavior induced by an approximating model.2In a self-conﬁrming equilibrium,beliefs are correct about events that occur with positive probability in equilibrium.The approxi-mating model is‘wrong’only in its description of events that occur with zero probability in equilibrium.Among the objects determined by a self-conﬁrming equilibrium are theESCAPING NASH INFLATION3 parameters of the government’s approximating model.While the self-conﬁrming equi-librium concept differs formally from a Nash(or time consistent)equilibrium,3it turns out that the self-conﬁrming equilibrium outcomes are the time-consistent ones.Thus,the suboptimal time consistent outcome continues to be our benchmark.Like a Nash equilibrium,a self-conﬁrming equilibrium restricts population objects (mathematical expectations,not sample means).We add adaptation by requiring the government to estimate its model from historical data in real time.We form an adap-tive model by having the monetary authority adjust its behavior rule in light of the latest model estimates.Thus,we attribute‘anticipated utility’behavior(see Kreps(1998))to the monetary authority.Following Sims(1988),we study a‘constant gain’estimation al-gorithm that discounts past observations.Called a‘tracking algorithm’,it is useful when parameter drift is suspected(see e.g.Marcet and Nicolini(1997)).Results from the literature on least squares learning(e.g.,Marcet and Sargent(1989a), Woodford(1990),Evans and Honkapohja(1998))apply and take us part way,but only part way,to our goal of characterizing the dynamics of the adaptive system.That litera-ture shows how the limiting behavior of systems with least squares learning is described by an ordinary differential equation called the‘mean dynamics’.They describe the(un-conditionally)average path of the government’s beliefs,in a sense that we shall describe precisely.For our model,the mean dynamics converge to the self-conﬁrming equilibrium and the time consistent outcome.Thus,the mean dynamics do not account for the recur-rent stabilizations in the simulations of Sims(1988),Chung(1990),and Sargent(1999). We show that these stabilizations are governed by another deterministic component of the dynamics,described by another ODE,the‘escape’dynamics.They point away from the self-conﬁrming equilibrium and toward the Ramsey(or optimal-under-commitment) equilibrium outcome.So two sorts of dynamics dominate the behavior of the adaptive system.(1)The mean dynamics come from an unconditional moment condition,the least squaresnormal equations.These dynamics drive the system toward a self-conﬁrmingequilibrium.4(2)The escape route dynamics propel the system away from a self-conﬁrming equilib-rium.They emerge from the same least squares moment conditions,but they areconditioned on a particular“most likely”unusual event,deﬁned in terms of the disturbance sequence.This most likely unusual event is endogenous.The escape route dynamics have a compelling behavioral interpretation.Within the conﬁnes of its approximate model,learning the natural rate hypothesis requires that the government generate a sufﬁciently wide range of inﬂation experiments.To learn even an imperfect version of the natural rate hypothesis,the government must experiment more than it does within a self-conﬁrming equilibrium.The government is caught in an experimentation trap.The adaptive algorithm occasionally puts enough movement into the government’s beliefs to produce informative experiments.4IN-KOO CHO,NOAH WILLIAMS,AND THOMAS J.SARGENT1.1.Related literature.Evans and Honkapohja(1993)investigated a model with mul-tiple self-conﬁrming equilibria having different rates of inﬂation.When agents learn through a recursive least squares algorithm,outcomes converge to a self-conﬁrming equi-librium that is stable under the learning algorithm.When agents use aﬁxed gain algo-rithm,Evans and Honkapohja(1993)demonstrated that the outcome oscillates among different locally stable self-conﬁrming equilibria.They suggested that such a model can explain wideﬂuctuations of market outcomes in response to small shocks.In models like Evans and Honkapohja(1993)and Kasa(1999),the time spent in a neighborhood of a locally stable equilibrium and the escape path from its basin of at-traction are determined by a large deviation property of the recursive algorithm.As the stochastic perturbation disappears,the outcome stays in a neighborhood of a particular locally stable self-conﬁrming equilibrium(exponentially)longer than the others.This observation provided Kandori,Mailath,and Rob(1993)and Young(1993)with a wayto select a unique equilibrium in evolutionary models with multiple locally stable Nash equilibria.An important difference from the preceding literature is that our model has a unique self-conﬁrming equilibrium.Despite that,the dynamics of the model resemble those for models with multiple equilibria such as Evans and Honkapohja(1993).With multiple locally stable equilibria,outcomes escape from the basin of attraction of a locally stable outcome to the neighborhood of another locally stable equilibrium.The fact that our model has a globally unique stable equilibrium creates an additional challenge for us, namely,to characterize the most likely direction of the escape from a neighborhood of the unique self-conﬁrming equilibrium.As we shall see,the most likely direction entails the government’s learning a good,but not self-conﬁrming,approximation to the natural rate hypothesis.anization.Section2describes the model in detail.Section3deﬁnes a self-conﬁrming equilibrium.Section4describes a minimal modiﬁcation of a self-conﬁrming equilibrium formed by giving the government an adaptive algorithm for its beliefs.Section5uses re-sults from the theory of large deviations to characterize convergence to and escape froma self-conﬁrming equilibrium.Section6shows that numerical simulations of escape dy-namics,like those in Sargent(1999),are well described by the numerically calculated theoretical escape paths.For the purpose of giving intuition about the escape dynamics, Section7specializes the shocks to be binomial,then adduces a transformed measure of the shocks that tells how particular endogenously determined unusual shock sequences drive the escape dynamics.Section8concludes.The remainder of this introduction de-scribes the formal structure of the model andﬁndings of the paper.1.3.Overview.The government’s beliefs about the economy are described by a vector of regression coefﬁcients.It chooses a decision rule that makes the stochastic process for the economy be.But for the stochastic process,the bestﬁtting model ofthe economy has coefﬁcients.A self-conﬁrming equilibrium is aﬁxed point of .The orthogonality conditions pinning down the bestﬁtting model can be expressed (1.1)ESCAPING NASH INFLATION5 We shall show thatwhereA self-conﬁrming equilibrium is a set of population regression coefﬁcients.We form an adaptive model by slightly modifying a self-conﬁrming equilibrium.Rather than usingpopulation moments toﬁt its regression model,the government uses discounted leastsquares estimates from historical samples.We study how the resulting adaptive systemconverges to or diverges from a self-conﬁrming equilibrium.Each period the govern-ment uses the most recent data to update a least squares estimate of its model co-efﬁcients,then sets its policy according to.This is what Kreps(1998)calls an anticipated utility model.The literature on least squares learning in self-referential sys-tems(see Marcet and Sargent(1989a),Marcet and Sargent(1989b),Woodford(1990),andEvans and Honkapohja(2000))give conditions under which the limiting behavior of thegovernment’s beliefs are nearly deterministic and approximated by the following ordi-nary differential equation(ODE)is governed by the uniqueness and stability of the stationary points of the ODE.Our model has a unique self-conﬁrming equilibrium.It supports the high inﬂationtime-consistent outcome of Kydland and Prescott(1977).The ODE(1.3),(1.4),is veryinformative about the behavior of our adaptive model.It is globally stable about theself-conﬁrming equilibrium,and describes how the adaptive system is gradually drawnto the self-conﬁrming equilibrium.But to understand how the sample paths recurrentlyvisit the better low-inﬂation outcome,we need more than the ODE(1.3,1.4).Until our work,such‘escape dynamics’had not been characterized analytically.Thispaper shows that they are governed by the ODE6IN-KOO CHO,NOAH WILLIAMS,AND THOMAS J.SARGENTrate hypothesis.Thus,like the mean dynamics,the escape dynamics are deterministic. We verify that these deterministic dynamics do a good job of describing the simulations. As Sims(1988)and Sargent(1999)emphasize,the evolution of beliefs during an es-cape is economically interesting because then the government discovers a good enough approximate version of the natural rate hypothesis to cause it to pursue superior policy that is supported by beliefs that are‘wrong’in the sense that they are not a self-conﬁrming equilibrium.Nevertheless,in another sense those beliefs are more‘correct’than those in a self-conﬁrming equilibrium because they inspire the government to leave the‘experi-mentation trap’that conﬁnes it within a self-conﬁrming equilibrium.2.S ETUPTime is discrete and indexed by.Let be an i.i.d.sequence of random vectors with mean zero and covariance matrix.Let,respectively,be the unemployment rate,the rate of inﬂation,the public’s expected rate of inﬂation,and the systematic part of inﬂation determined by government policy.The government sets ,the public sets,then nature chooses shocks that determine and.The economy is described by the following version of a model of Kydland and Prescott(1977):(2.8)(2.9)(2.10)(2.11)where(2.12)Equation(2.8)is a natural rate Phillips curve;(2.9)says that the government sets inﬂa-tion up to a random term;(2.10)imposes rational expectations for the public;(2.11)is the government’s decision rule for setting the systematic part of inﬂation.The de-cision rule is a function of the government’s beliefs about the economy,which are parameterized by a vector.For some purposes below we consider the simpler model in which the government only estimates a static regression of unemployment on inﬂation and a constant(i.e. ).We call this the static model.Since there is no temporal dependence in(2.8),(2.9),all of the temporal dependence in the model comes through the government’s beliefs.Under the static model speciﬁcation,the government’s control rule can be calculated explicitly, allowing some of our characterizations to be sharper.2.1.The government’s beliefs and control problem.The government’s model of the economy is a linear Phillips curve(2.13)where the government treats as a mean zero,serially uncorrelated random term beyond its control.We shall eventually restrict,but temporarily regard it as arbitrary.TheESCAPING NASH INFLATION7 government’s decision rule(2.11)solves the problem:(2.14)where denotes the expectations operator induced by(2.13)and the minimization is subject to(2.13)and(2.9).We call problem(2.14)the Phelps problem.Versions of it were studied by Phelps(1967), Kydland and Prescott(1977),Barro and Gordon(1983),and Sargent(1999).We identify three salient outcomes associated with different hypothetical government’s beliefs: Belief1.If,then the Phelps problem tells the government to set for all.This is the Nash outcome of Sargent(1999),i.e.,the time-consistent outcome of Kydland and Prescott(1977).Belief2.If,for any,the government setsfor all.This is the Ramsey outcome,i.e.,the optimal time-inconsistent outcome of Kydland and Prescott(1977).Belief3.If the coefﬁcients on current and lagged’s sum to zero,then asfrom below,the Phelps problem eventually sends arbitrarily close to.Under the actual probability distribution generated by(2.8),(2.9),(2.10),the value of the government’s objective function(2.14)is larger under the outcome than under outcome.Under Belief1,the government perceives a trade-off between in-ﬂation and unemployment and sets inﬂation above zero to exploit that trade-off.Under Belief2,the government perceives no trade-off,sets inﬂation at zero,and accepts what-ever unemployment emerges.Under Belief3,the government thinks that although there is a short-term trade-off between inﬂation and unemployment when,there is no ‘long-term’trade-off.Through the workings of an‘induction hypothesis’that opens an apparent avenue by which the government can manipulate the current position of the Phillips curve(see Cho and Matsui(1995)and Sargent(1999)),the Phelps problem tells the government eventually to set inﬂation close to zero when is close to.In a common-knowledge model in which(2.13)is dropped and replaced by the as-sumption that the government knows the model,the outcome emerges as what Stokey(1989)and Sargent(1999)call the Nash outcome,and emerges as the Ram-sey outcome.In the common-knowledge model,these varying outcomes reﬂect different timing protocols and characterize a time-consistency problem analyzed by Kydland and Prescott.The mapping from government beliefs to outcomes is interesting only when the gov-ernment’s beliefs might be free.Our equilibrium concept,a self-conﬁrming equilibrium, restricts those beliefs,and thereby narrows the outcomes relative to those enumerated above.However,the mapping from beliefs to outcomes play a role during escapes from self-conﬁrming equilibria.8IN-KOO CHO,NOAH WILLIAMS,AND THOMAS J.SARGENT3.S ELF-CONFIRMING EQUILIBRIUM3.1.Restrictions on government’s beliefs.Deﬁne and(3.15)Let denote the history of the joint shock process up to.Evidently,from(2.8),(2.9),(2.10),(2.11),and therefore the process are both functions of:(3.16)Deﬁnition3.1.A self-conﬁrming equilibrium is a that satisﬁes(3.17)The expectation in(3.17)is taken with respect to the probability distribution generated by(2.8),(2.9),(2.10),(2.11).Notice that is the time value of the object set to zero by the following least squares orthogonality condition:(3.18)Equations(3.18)are the orthogonality conditions that make in(2.13)a least-squares regression.Condition(3.17)thus renders the government’s beliefs consistent with the data.Condition(3.17)can be interpreted as asserting that is aﬁxed point in a mapping from the government’s beliefs about the Phillips curve to the actual Phillips curve.Thus, let(3.19)and.Then notice that(3.20)(3.22)Given a government model in the form of a perceived regression coefﬁcient vector and the associated government best response function,is the actual least squares regression coefﬁcient induced by.Thus,maps government model to a bestﬁtting model.Equation(3.22)shows that(3.17)asserts that,so thatESCAPING NASH INFLATION9 the government’s model is the bestﬁtting model.See Marcet and Sargent(1989a)for a discussion of the operator in a related class of models.Elementary calculations show that there is a unique self-conﬁrming equilibrium.It cor-responds to the beliefs(1)mentioned above.These beliefs support the Nash equilibrium outcome in the sense of Stokey(1989)and Sargent(1999).4.A DAPTATION4.1.Discounted least squares updating of.We modify the model now to consist of (2.8),(2.9),(2.10)as before,but replace(2.11)with(4.23)where remains the best-response function generated by the Phelps problem,and is the government’s time estimate of the empirical Phillips curve.The government estimates by the following recursive least squares algorithm:(4.24)(4.25)where is a gain parameter that determines the weight placed on current observations relative to the past.In this paper we consider the case in which the gain is constant.We want to study the behavior of system formed by(2.8),(2.9),(2.10),(4.23),(4.24)and(4.25).4.2.Mean dynamics.Weﬁnd theﬁrst important component of dynamics by adapting the stochastic approximation methods used by Woodford(1990),Marcet and Sargent (1989a),and Evans and Honkapohja(2000).We call this component the mean dynamics because it governs the(unconditionally)expected evolution of the government’s beliefs. While previous applications of stochastic approximation results in economics have gener-ally considered recursive least squares with decreasing gain,we consider the case where the gain is constant.5Broadly similar results obtain in the constant and decreasing gain cases,but there are important differences in the asymptotics and the sense of convergence that we discuss below.To present convergence proofs,it helps to group together the components of the gov-ernment’s beliefs into a single vector.Deﬁne(4.26)Then the updating equations(4.24),(4.25)can be written(4.27)Now break the“update part”into its expected and random components.Deﬁneis the mean of deﬁned as(4.28)5See Evans and Honkapohja(2000)for extensive discussion of constant gain algorithms.10IN-KOO CHO,NOAH WILLIAMS,AND THOMAS J.SARGENTwhere(4.29)Then we can write the composite dynamics as(4.30))over time.As in the decreasing gain case,we can show that the asymptotic behavior of(4.30)is governed by an ODE,but the estimates converge in a weaker sense.Speciﬁcally,decreas-ing gain algorithms typically converge with probability one along a sequence of iterations as,but constant gain algorithms converge weakly(or in distribution)as across sequences of iterations,each of which is indexed by the gain.Note that we can rewrite(4.30)as(4.31)This equation resembles aﬁnite-difference approximation of a derivative with time step ,but is perturbed by a noise term.The convergence argument deﬁnes a continuous time scale as,and interpolates between the discrete iterations to get a continuous process.Then by letting,the approximation error in theﬁnite difference goes to zero,and a weak law of large numbers insures that the noise term becomes negligible. We are left with the ODE:(4.33)We need the following set of assumptions.For reference,we also list the original num-ber in Kushner and Yin(1997).To emphasize the asymptotics,we include the superscript on the parameters denoting the gain setting.Assumptions A.A8.5.0:The random sequence is tight.6A8.5.1:For each compact set is uniformly integrable.7A8.5.3:For each compact set the sequence6A random sequence is tight if7A random sequence is uniformly integrable ifA8.5.4a:The ODE that is asymptotically stable.8A8.1.6:The functionthat is the self-conﬁrming equilibrium,the estimate sequence converges weakly to the self-conﬁrming equilibrium.Therefore,with high probability,as and we would expect the government’s beliefs to be near their self-conﬁrming values,and the economy to be near the Nash outcome.However,in the next section we shall see that the beliefs can recur-rently escape the self-conﬁrming equilibrium.Although the impact of noise terms goes to zero with the gain,for a given,“rare”sequences of shocks can have a large impact on the estimates and the economy.5.E SCAPEIn this section we determine the most likely rare events and how they push the gov-ernment’s beliefs away from a self-conﬁrming equilibrium.To this end,weﬁrst present some general results from the theory of large deviations,a general method for analyzing small probability events.We then present results from Williams(2000),who applies these general results analytically to characterize the escape dynamics.5.1.Escape dynamics as a control problem.Throughout,we will only be interested in characterizing the escape problem for the Phillips curve coefﬁcients.This motivates the following deﬁnition.Deﬁnition5.1.An escape path is a sequence of estimates that leave a set containing the limit pointfor someFollowing a convention in the large deviation literature,we set the initial point of an escape path to be the stable point,let be the set of all escape paths.For each,deﬁne8A point as and for each there exists an such that if for allDeﬁnition5.2.Let be the(ﬁrst)exit time associated with escape path. An absolutely continuous trajectory is a dominant escape path ifwill occur along with very high probability,if an escape ever occurs.To analyze the escape dynamics,we adapt the general results of Dupuis and Kushner (1989),which are themselves extensions of the theory of Freidlin and Wentzell(1984) for stochastic approximation models.After presenting some general results,we apply results of Williams(2000),who obtains explicit solutions of the escape dynamics that can be used to interpret the simulations calculated earlier by Sims(1988),Chung(1990),and Sargent(1999).Given the recursive formula(4.30),deﬁne the-functional as(5.35),and with the evolution of following the mean dynamics conditional on .(We let for trajectories that are not absolutely continuous.)In the context of continuous time diffusions,Freidlin and Wentzell(1984)characterized the dominant escape path as a solution of a variational problem.Their results have been extended to discrete time stochastic approximation models by Dupuis and Kushner(1985)and Dupuis and Kushner(1989).We adapt these results in the following theorem,whose main object is the solution of the following variational problem:(5.38)for someThe minimized value(1)Suppose that the shocks are i.i.d.and unbounded but that there exists a algebraand constants such that for all anda.s.Then we have:for some(2)If the shocks are i.i.d.and bounded,andbe the terminal point of the dominant escape path.Then for any and:.The next three parts establish stronger results under the assumption that the errors are bounded.Part(2)shows that under bounded errors,the asymptotic inequality in part(1)becomes an asymptotic equality. Part(3)shows that for small the time it takes beliefs to escape the self-conﬁrming equi-librium becomes close to.It is known(see Benveniste,Metivier,and Priouret(1990)for example)that the asymptotic distribution of Markov processes can be characterized by the Poisson equa-tion,so it is natural that it appears here.This analysis then leads to a representation of the-functional as a quadratic form in,with a normalizing matrix that depends on the solution of the Poisson equation associated with.In general the solution of the Poisson equation can itself be a difﬁcult problem,as it involves solving a functional equation.However in the important linear-quadratic-Gaussian case(which includes our model),the problem can be solved in the space of quadratic functions,and therefore the Poisson equation reduces to a matrix Lyapunov equation.This provides a tremendous simpliﬁcation,as there are efﬁcient numerical methods for solving Lyapunov equations. We summarize these arguments in the following theorem and remark.Theorem5.4.Suppose that Assumptions A hold,that follows a stationary functional au-toregression with a unique stationary distribution and Lipschitz continuous mean and variance functions,and that the function is Lipschitz continuous in.Then there is a matrix-valued function such that the dominant escape path and rate function can be determined by solving the following variational problem:(5.39)subject to(5.41)(5.42)for someProof.See Williams(2000).Remark5.5.In our model,follows a linear autoregression,the are i.i.d.normal,and is a quadratic function of.Then is a fourth moment matrix that can be calculated explicitly by solving matrix Lyapunov equations described in Appendix C.This theorem provides a clearer interpretation and analysis of the variational problem. The escape dynamics perturb the mean dynamics by a forcing sequence.Then is a quadratic cost function that measures the magnitude of the perturbations during the episode of an escape.In particular,we can think of(5.39)as a least squares problem, where plays the role of a covariance matrix.If we had then the beliefs adhere to the mean dynamics,and the cost would be zero.For the beliefs to escape from.Toﬁnd the dominant escape path,we solve the control problem in(5.39).We form the Hamiltonian with co-states for the evolution of:It is easy to verify that the Hamiltonian is convex,so theﬁrst order conditions are nec-essary and sufﬁcient.Taking theﬁrst order conditions,we see that the dominant escape path is characterized by the following set of differential equations:The path that achieves the minimum is the dominant escape path.This path characterizes the evolution of the parameters on the most likely path away from the stable point.The minimized value.There is a unique self-conﬁrming equilibrium,depicted in Figure2.It has.To solve the problem numerically,it helps to recast the boundary value problem as an initial value problem.In the ODE system(5.43)and boundaries(5.42),the only com-ponents left undetermined are the initial conditions for the co-states.We can solve the problem by minimizing over these initial conditions,and determine the escape times and。

mbist问题解决报告

1.手工输入选项,更改系统语言为英语,删除中文输入法;之前就是在英文语言环境下操作的,出现上述手动输入不进去的问题; 2．输入文件：Library Model:是用Mentor语言描述的,用来产生RTL BIST collar,并且将memory的RTL 设计与BIST collar映射起来,模型里面通常定义了存储器的读写周期;MBISTArchitect dofile：mbistarchitect的可执行文件,通常包含了关于产生BIST电路的命令;ROM Content Fileoptional：只有在给ROM生成BIST电路时才会用到,它说明了存储在ROM存储器中每一行的十六进制的值,用来为ROM存储器提供压缩信号;此次只测试了RAM,所以没有用到输出文件：HDL BIST Circuitry：包含了生成的controller的RTL代码和memory collar的RTL代码,其中controller包含了一个有限状态机去控制你选择的存储器测试算法的操作,还包含了地址产生器,写数据生成器,期望的数据生成器和控制信号生成器;Controller通常还包括一个比较器来判断测试结果的正确与否;BIST collar不仅包含测试的多路选择器和扫描的bypass逻辑,还从你原来的设计中实例化了存储器;当你controller不使用比较器时collar中还会包含一个压缩器;Synthesis Driver Script：用来给DC做综合用的,可以在DC中将MBIT 进行优化;HDL BIST/RAM Connection Model ：实例化了BIST 电路,并将所有的端口连接起来;HDL Testbench ：实例化了connection 模型,并提供激励来启动BIST 电路的测试算法,在测试结束时会报告测试状态;文件层次图：其中,controller 和collar 都包含在文件中,collar 还将存储器实例化了;3．外部pin 的输入管脚有20个,输出管脚有5个;它们分别与controller 和collar 的对应关系如下：外部pin ：in hold_l controller: inhold_ltest_h test_hbist_clk bist_clkrst_l rst_lAA_0 collar:in AAAB_0 ABDA_0 DADB_0 DBWENA_0 WENAWENB_0 WENBCLKA_0 CLKACLKB_0 CLKBOENA_0 OENAOENB_0 OENBCENA_0 CENACENB_0 CENBbp_clk_0 bp_clkTest_mode_0 Test_modescan_en_0 scan_enscan_in_0 scan_inout test_done controller:out test_done fail_h fail_hQB_0 collar:out QBQA_0 QAscan_out_0 scan_out 4．表头呢输入输出5．Modelsim工程打包见文件夹7. Delay 不同时的modelsim图加入（1）当延迟是时,结果如下：总结：当延迟为时,输出没有数据,而且没有数据的地方跟时钟也没有延迟;2当延迟为1时结果如下：总结：如上图所示,有数据输出,输出与时钟延迟为1ns;3当延迟为时结果如下：总结：如上图所示,有数据输出,但是延迟为1ns; 4当延迟为时结果如下：总结：如上图所示,有数据输出,但是延迟为2ns;由此可见,设置的延迟精确到ps的它都取了最大的整数延迟;8.涉及到的工具：Mentor Graphics公司下的：ModelSim vertion 波形仿真MBISTArchitect 生成bist电路9. CLK/RST 的专门描述包含RAM 不使用CLK如何能工作的问题CLK信号有两个：bist_clk bypass_clk其中bist_clk是在controller里存在,在测试时提供时钟信号;而bypass_clk是给bypass模块提供时钟的;RAM其实是有时钟信号的,testbench中给其加了时钟信号,而且它的时钟信号是与bist_clk同步的;RST信号：controller上有一个复位信号rst_l,是控制comtroller的; 11．软件安装步骤：安装步骤：1,Copy '’to linux;2,Invoke the ixe.Note: If 'uudecode' is missing, install ''3,-D Agree4,Installation starts at current dir it will also install doc, if it finds it under current dir.5,获得网卡地址,在自己电脑生成6,将获得的复制到软件安装目录下7,修改环境变量MGC_HOME other_mentor_install_dirMGLS_LICENSE_FILE fast license checkout, for all mentor products 8,启动软件;12．MarchC算法解释：以下测试的都是DA端口wBackgroundUp：写操作,地址从低到高全写入全0,初始化地址空间; rwrInvBackgroundUp：读写读操作,从低地址开始,先读,因为此时没有写操作,所以读出来的数据还是之前初始化后的全0,然后将全1写入,再读,此时读出来的就是写入的全1了,然后地址依次升高,重复之前的读写读操作;rwrBackgroundUp：读写读操作,由于之前第二步操作后地址已被写入全1;从低地址开始,先读,此时为全1,再写入全0 ,再读就是全0,地址依次升高,重复读写读的操作;rwrInvBackgroundDown：读写读操作,上一步操作结束后地址全被写为0;从高地址开始,先读数据,为全0,再写1,再读就是全1,地址依次降低,重复读写读的操作;rwrBackgroundDown：读写读操作,上一步操作结束后地址全被写为1;从高地址开始,先读数据,为全1,再写0,再读就是全0,地址依次降低,重复读写读的操作;rBackgroundDown：读操作,上一步操作结束后地址全被写为0;从低地址开始,读数据,读出来的数据都为全0,地址依次升高,重复此操作;当A端口测试完毕后接着测试B端口,依照以上的步骤;13．Step by Step的生成方法GUI, TCL, TCL的脚本逐条解释; TCL：/home/soc/Mentor_DFT_MBist/bin/mbistarchitect -bistgen \ libs/ \ transcripts/ -replace \ \ 终端上启动图形界面：2.点击Memory Models3.从指定路径中加载存储器模型,路径可以自己指定;4.点击Report Environment,点击run5.设置输出文件名称保存在指定路径下6.点击Save Bist,保存生成的文件;注释：当你用modelsim仿真时,需要加载的文件时四个,分别是、、、;当你观察波形时只需要查看controller的波形就可以了,而且也可以同时关注一下collar中ram的时钟信号;原则上ram上加的是系统给的信号,而测试时并没有系统给的信号,所以在testbench中给它加的就是与bist_clk同步的时钟信号;问题1：文档格式要求,做成表格或加序号,层次清晰;如果有并列项尽量用表格;问题2：硕士论文格式;问题3：信号怎么穿越到顶层。

【计算机应用】_代理技术_期刊发文热词逐年推荐_20140727

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ignoredeclarationexceptions参数 -回复

ignoredeclarationexceptions参数-回复什么是[ignoredeclarationexceptions参数]？在编程中，声明异常是指在方法或函数的声明中明确指定可能会抛出的异常类型。

当调用一个声明了可能会抛出异常的方法时，编译器通常要求处理或传递该异常，以保证程序的健壮性和可靠性。

而ignoredeclarationexceptions参数的存在，则意味着允许调用者忽略方法或函数声明中所列的异常类型。

在某些情况下，这个参数可以用来简化代码流程，但过度使用它可能会导致代码的错误处理变得模糊或不完善。

为什么要[ignoredeclarationexceptions参数]？使用ignoredeclarationexceptions参数的主要原因是为了处理某些特定的业务逻辑或框架要求。

有时候，我们可能会有意选择忽略某些异常，尤其是在处理复杂的底层代码、第三方库或框架时。

通过忽略异常，我们可以在某些场景下简化代码逻辑，提高代码的可读性和易用性。

然而，在使用ignoredeclarationexceptions参数的同时，我们必须仔细权衡风险，以确保我们对异常的忽略不会导致程序的不稳定或不安全。

如何使用[ignoredeclarationexceptions参数]？当我们决定使用ignoredeclarationexceptions参数时，有一些关键的步骤需要遵循，以确保我们正确地处理和在适当的时机忽略异常。

以下是一些基本的步骤：第一步：确定使用ignoredeclarationexceptions参数是合适的情况。

在某些业务逻辑中，我们可能会遇到一些比较常见的异常，但在特定场景下，我们可能已经通过其他方式处理了这些异常，或者它们不会对业务逻辑产生重要影响。

这时候，考虑使用ignoredeclarationexceptions参数可能是合理的选择。

第二步：仔细阅读方法或函数的文档和声明，了解声明的异常类型和可能的异常情况。

saml断言格式

saml断言格式SAML断言（SAML Assertion）是SAML协议中用于表示身份信息的一种数据结构，它包含了一些关于个体（通常是用户）的身份验证信息。

SAML 断言的格式是基于XML的，并且遵循一定的语法和结构。

一个典型的SAML断言包含以下元素：1. `Assertion`元素：这是断言的根元素，包含了其他所有元素。

2. `Issuer`元素：用于标识断言的发行者，通常是身份提供者（Identity Provider）。

3. `Subject`元素：包含关于个体（用户）的信息，例如用户名或唯一标识符。

4. `Conditions`元素：定义了断言的有效期和约束条件，例如时间范围和允许的用途。

5. `AttributeStatement`元素：包含了个体的属性信息，例如姓名、邮箱地址等。

6. `AuthenticationStatement`元素：描述了个体的身份验证信息，包括使用的验证方法和验证结果。

以下是SAML断言的一个简单示例：```xml<Assertion xmlns="urn:oasis:names:tc:SAML::assertion"IssueInstant="T12:00:00Z"Version=""><Issuer><Subject><NameID>john_doe</NameID></Subject><AuthenticationStatementAuthenticationMethod="urn:oasis:names:tc:SAML::ac:password" AuthenticationInstant="T12:00:00Z"><Subject>john_doe</Subject></AuthenticationStatement></Assertion>```上述示例中，断言包含了发行者、主体、身份验证声明等信息，这些信息可用于身份验证和授权场景中。

BinomialLinkFunctions：二项链接功能

beetles killed were noted. The data are in the
following table:
Example (continued)
> beetle<-read.table("BeetleData.txt",header=TRUE)
> head(beetle)
Dose Num.Beetles Num.Killed
(Intercept) -34.935
2.648 -13.19 <2e-16 ***
Dose
19.728
1.487 13.27 <2e-16 ***
--Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
(Dispersion parameter for binomial family taken to be 1)
yi

i 1
n
e
xi T ˆ
• Logit:
pˆ i
• Probit:
pˆ i ( xiT ˆ )
• C Log Log:
pˆ i 1 exp{ exp[ xiT ˆ ]}
1 e
xi T ˆ
Differences in Link Functions
probLowerlogit <- vector(length=1000)
family = binomial) > summary(logitmodel)
> probitmodel<-glm(cbind(Num.Killed,Num.Beetles-Num.Killed) ~ Dose, data = beetle,

VC的工程设置解读Project—Settings

VC的工程设置解读Project—SettingsVC工程设置可能会直接影响到工程的正确性，有时是BUG产生的直接原因，在出现莫名其妙的错误，首先应考虑到是否是工程设置有问题，这无论对于开发还是测试，都是很必要的，本文大致介绍一下工程设置选项。

工程选项的快捷建是Alt+F7, 左边的列表可以选择要设置的工程编译方式（Debug或Release），如果多个工程，还可以选择要设置的工程。

右边是一个属性页，内容十分丰富，依次是：General , Debug , C/C++ , Link , Resource , MIDL , Browse Info , Custom Build , Pre-link Step , Post-build step下面主要介绍一下我们常用到的选项：一、General: 设置工程的一般特性，组合框为是否选用MFC静态库，默认为共享的DLL方式，对一些不支持MFC42的机器环境来说，选择静态编译还是有必要的。

底下的两个编辑框表示编译中的文件输出路径。

二、Debug：设置工程调试的选项。

1.Excutable for debug session : 如果是dll的工程，需要指定启动它的exe文件路径，如果是exe工程，默认当前工程。

2.Work directory 设置调试程序的工作路径，默认exe当前路径3.Program arguments 程序启动命令行参数，作控制台程序的时候经常要用三、C/C++ : 这一页内容很多，选择项通过Category(种类)来设置，包括：1.General2.Warning leve 警告级别，VC默认为3，一般不更改3.Optimizations优化级别，DEBUG下设为Disable(Debug),就是不优化，在追求效率或者编译结果的时候可以选择最大速度或最小尺寸的选项，不过微软不保证优化的准确性。

4.Waring as error : 不用多说了，经常忽略警告的人不会选这项吧？5.Generate browse info : 产生浏览信息，在编辑调试加了一些功能，单会产生很大的编译文件，建议不要选。

翻译

General Approach to Simulation模拟的一般方法In the PRO/II Graphical User Interface, the fields for operations that you are required perform, and data fields where data entry is required, are always bordered in red. Data entry fields for items with supplied defaults are always bordered in green. After you have supplied information in a data entry field, the border color changes to blue. If you supply data that lies outside the normal range of values for an entry field, the value is marked with a yellow border.在PRO/II画面使用界面,你所需要执行的操作领域和数据入口要求的数据领域,经常是红色边界。

数据入口区的提示的错误条目常是绿色边界。

当你在数据入口区得到信息，边界的颜色就变为蓝色。

如果你提供的数据存在于入口正常排列值的外面，这个值用红色边界标记。

Problem data may be supplied in almost any order, and PRO/II warns you when required data are missing. However, it is still best to follow a logical path when supplying simulation data. Therefore, the following general approach is recommended for building a simulation flowsheet:有问题的数据可能出现在任何一个程序，并且当你需要的数据丢失时PRO/II会发出警告。

Abaqus(Standard)的过限制检查

Abaqus/Standard的过限制检查Abaqus/Standard的过限制检查包含以下几种：1、综合应用下列限制条件：基运动、边界条件、接触对、耦合限制、线性限制方程、点焊、多点限制、刚体限制、TIE限制等。

2、综合应用下列单元：连接器单元、耦合单元、特殊用途接触单元、具有不可压材料行为的单元。

对于一致的过限制（也称冗余限制，所有限制相互兼容），standard会自动求解。

对于不一致的过限制（所有的限制不能相互兼容），使用方程求解器自动探测。

standard中过限制识别方法：1、在前处理过程中，不必要的一致过限制将会自动清除（给出warning），而不一致的过限制将会导致前处理中断（给出error）。

a，多个TIE限制相互交叠，应当去除其中一个限制。

b，刚体内的两个TIE限制是多余的。

两个刚体表面之间的TIE限制，将会被BEAM连接器单元在参考点处替代。

c，刚体和变形体之间的TIE限制，刚体必须做主表面，变形体做从表面。

d，刚体之间有交叠，则两参考点之间生成BEAM梁单元。

e，TIE限制和边界条件重复定义，视情况而定f，刚体限制和边界条件冲突，sta会首先将应用在其他节点上的边界转移到参考点上，若不成功则终止分析。

g，一个刚体的其他节点之间有连接器单元，会被认为是冗余限制而被去除。

两个刚体之间的若有BEAM单元，则其他单元都会被去除。

两刚体之间的连接器单元施加了过量的平动和转动限制，若其中没有BEAM或者WELD，则提示过限制告警，这种情况下，连接器单元不会主动消失，因为可能导致欠限制（两个相对运动的刚体只需要3个平动自由度），因此准确的连接器单元的施加很重要。

h，运动耦合限制和刚体重合时，刚体节点上的运动耦合限制会被去除。

分布耦合限制和刚体重合时，模型不会过限制。

i，边界条件不应当施加在分布耦合限制的节点上。

2、在分析过程中，由于接触条件在变化，涉及接触的过限制，只有一小部分，可能在求解过程中会自动消失。

关于Maxwell参数化扫描时添加calculations报错的说明

关于Maxwell参数化扫描时添加calculations报错的说明当需要考查某一物理量改变时，对其他量的影响，这时需要用到参数化扫描的功能。

以同步发电机为例，常常需要考察不同励磁电流下，空载电压的大小，以便绘制空载特性曲线。

这时，可以将励磁电流作为变量，然后扫描之,具体操作为：右键Optimetrics，选择add parametric，通过add定义励磁电流变化范围。

在calculations里面，点击左下角setup calculations,report type选择transient,parameter选择moving1,category选择winding，quantity 选择A相induced voltage,function选择none。

这时，点击add calculation，done，就会发现出现红叉叉，系统提示“calculation must be a dimension reducing ranged function,when using solution'setup1:transient'”。

之所以出现这个错误，原因就在于定义的A相induced voltage是一个函数，是随时间变化的量，而软件要求A相induced voltage也就是calculation expression必须是“single, real number”，因此在上述操作的基础上，还需点击右上角的Range function，category选择math，function选择rms，点击ok。

这时，再add calculation，done，就正确了。

以上操作的目的是，通过扫描励磁电流和A相电压有效值的关系，实现了绘制同步发电机空载特性曲线的功能。

现在，该知道错在哪里，以及如何避免出错了吧？其实，setup calculations功能完全多此一举，即使这个地方不设置，求解完成后，后处理一样可以得到表达式与扫描量的关系，不会的同学可自己试着发掘一下Maxwellhelp文件为Maxwell2D/3D的瞬态求解设置铁芯损耗一、铁损定义（coreloss definition）铁损的计算属性定义（CalculatingPropertiesforCoreLoss(BPCurve)要提取损耗特征的外特性（BP曲线），先在View/EditMaterial对话框中设置损耗类型（CoreLoss Type）是硅钢片（ElectricalSteel）还是铁氧体（PowerFerrite）。

常用外贸英文缩写

QTY-QUANTITY-数量QTD-QUOTED-引述，报价QL/TY-QUALITY-质量，品质QR-QUARTER-四分之一QSTN-QUESTION-问题QT-QUART-夸脱QUE-QUOTE-报价QUOTN-QUOTATION-报价单R-ARE-是RCNT-RECENT-最近RCVD;REC'D-RECEIVED-收悉RECPT-RECEIPT-收到，收据REF-REFERENCE-参考RELATNS-RELATIONS-关系REP-REPRESENTATIVE-代表REQRMTS-REQUIREMENTS-要求RGD-REGISTERED-已登记，挂号RGDS-REGARDS-此致RGRT-REGRET-遗憾，抱歉R.I.-RE-INSURANCE-再保险REM-REAM-令RGDG-REGARDING-关于RM-REMITTANCE-汇款R.O.-REMITTANCE ORDER-汇款委托书RPT-REPEAT-重复RQR-REQUIRE-要求R.S.V.P.-REPONDEZ S'IL VOUS PLAIT-敬候函复R.Y.T.-REPLYING TO YOUR TELEGRAM-回复贵电S-SHILLING-先令S-IS-是$;D-DOLLAR-美元SB-SOMEBODY-某人S.C.-SEE COPY-请阅副本SCHDL-SCHEDULE-计划S/D-SIGHT DRAFT-即期汇票SDY-SUNDRIES-杂货SE-SECURITIES-抵押品SEC-SECRETARY-秘书SEPT-SEPTEMBER-九月SGD-SIGNED-已签署SHDB-SHOULD BE-应该SHLB-SHALL BE-将SHIPG-SHIPPING-装船SHIPT-SHIPMENT-船货SHIPD-SHIPPED-已装船SYST-SYSTEM-系统S/N-SHIPPING NOTE-装船通知SOC-SOCIETY-社会，协会S.O.S.-SAVE OUR SHIP-求救信号SPEC-SPECIFICATION-规格SQ-SQUARE-平方SS;S.S.-STEAMSHIP-轮船ST-STREET-街道S.T.-SHORT TON-短吨STG-STERLING-英国货币STAND-STANDARD-标准STANDG-STANDING-站立STH-SOMETHING-某事STL-STILL-仍然STOR-STORAGE-仓库费STR-STEAMER-轮船SUBJ-SUBJECT-须经，受…支配SUN-SUNDAY-星期日SZS-SIZE-尺码T-TON-吨T.A.-TELEGRAPHIC ADDRESS-电挂TDY-TODAY-今天TEL NR-TELEPHONE NUMBER-电话号码TK-TAKE-取TKS-THANKS-感谢T.L.-TOTAL LOSS-全部损失THFR-THEREFORE-因此THUR-THURSDAY-星期四THRU-THROUGH-通过T.M.O.-TELEGRAPHIC MONEY ORDER-电汇TOB-TO BE-是TOM-TOMORROW-明天TONN-TONNAGE-吨数T.P.N.D.-THEFT,PILFERAGE & NON-DELIVERY-盗窃提货不着险T/R-TRUST RECEIPT-信托收据TRVL-TRAVEL-旅行T/T-TELEGRAPHIC TRANSFER-电汇U-YOU-你ULT-ULTIMO-上月UR;YR-YOUR-你的URGG-URGING-催促UGT-URGENT-急迫V-WE-我们VIA-BY WAY OF-经由VIZ-VADE LICET,NAMELY-即V'L-WE'LL-我们将VOL.-VOLUME-卷，册，体积，量VOY-VOYAGE-航海，航次V.P.-VICE PRESIDENT-副社长，副经理，副总裁VR-OUR-我们的V.V.-VICE VERSA-反之亦然W-WITH-在一起W.A.-WITH AVERAGE-水渍险WDTH-WIDTH-宽度WHF-WHARF-港口WK-WEEK-周WL-WILL-将WLB-WILL BE-将W.R.-WAR RISK-战争险WT-WEIGHT-重量W/OUT-WITHOUT-没有WUD-WOULD-将W/W-WAREHOUSE TO WAREHOUSE-仓之仓WZ-WITH-在一起X MAS-CHRISTMAS-圣诞节X.P.-EXPRES PAYE = EXTRA MESSAGE PAID-已另函奉上YD-YARD-码YR-YEAR,YOUR-年，你的£-STERLING,STG-英镑$-DOLLAR,USD-美元#-NUMBER,NO.,NR.-号数，编号&-AND,N-和360°-360°DEGREES-360度@-AT-单价=-IS EQUAL TO,EQUALS-等于+-PLUS-加--MINUS-减CL-CLASS;CLAUSE;CLERK-级，条款，职员CM-CENTIMETRE-公分CMDTY-COMMODITY-商品C.N.;C/N-CREDIT NOTE-收款通知，货款清单CNCL-CANCEL-撤销CNCLSN-CONCLUSION-结论，商定CNSDRTN-CONSIDERATION-考虑CNT-CONTRACT-合同，契约C.O.-CERTIFICATE OF ORIGIN-原产地证明书C/O-CASH ORDER;CARE OF-现金订单，转交CO;COY-COMPANY-公司，商行C.O.D.-CASH ON DELIVERY-付款交货COLLR-COLLECTOR-收款员COM,COMM,COMMN-COMMISSION-佣金CON.INV.-CONSULAR INVOICE-领事发票CONSGT,CONS'T-CONSIGNMENT-委托销售，寄售CONT,CONTR-CONTRACT-合同，契约CONTG-CONTAINING,CONTINUING-包括，内容，继续CORP-CORPORATION-公司COOP-COOPERATION-合作C/P;C.PY.-CHARTER PARTY-租船契约C.P.A-CERTIFIED PUBLIC ACCOUNTANT-会计师CRT-CORRECT-正确，修正CR;CRED-CREDIT-贷方CSTMRS-CUSTOMERS-客户CTGE-CARTAGE-搬运费CUB-CUBIC-立方CUD-COULD-能CURR;CUR;CURT-CURRENT-流通的，现行的CURR ACCT-CURRENT ACCOUNT-往来账目，活期存款C.W.O.-CASH WITH ORDER-随订单付现CY-CURRENCY-货币D-ROMAN500-罗马数字500D/A-DOCUMENTS AGAINST ACCEPTANCE-承兑交单D.A.-DEBIT ADVICE-欠款报单D/A-DAYS AFTER ACCEPTANCE-承兑后若干日交单DBLE-DOUBLE-加倍DBT-DEBT,DEBIT-借，借方D/D D.D.-DEMAND DRAFT-即期汇票DE.;DEF-DEFERRED-延迟DEB-DEBENTURE-退税证明书DEBT-DEBTOR-借方DEC-DECEMBER-十二月DECSN-DECISION-决定DESCV-DECISIVE-决定性的DEG-DEGREE-等级，程度DELY-DELIVERY-交货DEM-DEMURRAGE-延期费DEP-DEPOSIT,DEPUTY-存款，代理DEPT;DPT-DEPARTMENT-部，科，处DEVELOPG-DEVELOPING-发展D.F;D.FRT-DEAD FREIGHT-空舱费DIS-THIS-这个DISAPNTD-DISAPPOINTED-失望DRT-DRAFT-汇票DIA-DIAMETER-直径DIFF-DIFFERENCE-差额，剩余DIR-DIRECTOR-董事DIS;DISC;DISCT-DISCOUNT-折扣DIST-DISTRICT-地区DIV-DIVIDEND-红利，股息D.K;DK-DOCK-船坞，码头DLS-DOLIARS-元DLT-DAY LETTER TELEGRAM-书信电DM-DECIMETRE-公寸D/N-DEBIT NOTE-欠款通知单，借方帐D/O;D.O.-DELIVERY ORDER-提货单DO;DTO-DITTO = THE SAME-同上DOC-DOCUMENT-文件DOZ,DZ-DOZEN-打D/P-DOCUMENTS AGAINST PAYMENT-付款交单DPTH-DEPTH-深度DIS D.S.DYS ST-DAYS AFTER SIGHT-见票后若干日付款DS;D'S-DAYS-若干日D.S.T.-DAYLIGHTSAVING TIME-夏令时DTL-DETAIL-详细DUP;DUPL-DUPLICATE-副本，俩份DURG-DURING-在...期间D.W.-DEAD WEIGHT-自重，净重EA-EACH-每一，各EC-ERROR CORRECTION-错误更正E.C.M.-CUROPEAN COMMON MARKET-欧洲共同市场ECOM-ECONOMY-经济EDIT;ED-EDITION-版E.G.EX.G.-EXEMPLI GRATIA = FOR EXAMPLE-例如ELEC-ELECTRICITY-电气E.M.F.-ELECTRO-MOTIVE-电动势ENC;ENCL-ENCLOSURE-附件ENG-ENGLAND,ENGLISH-英国ENTD-ENTERED-入账E.& O.E.-ERRORS AND OMISSIONS EXCEPTED-（账单上所标注的）错漏除外EQ-EQUAL,EQUIVALENT-相同，同值ESQ;ESQRE-ESQUIRE-先生阁下ET,AL.-ET ALII = AND OTHERS-及其他E.T.A.-ESTIMATED TIME OF ARRIVAL-估计到达的时间ETC.-ET CETERA = AND SO FORTH-等等E.T.D.-ESTIMATED TIME OF DEPARTURE-估计离开的时间EUR-EUROPE-欧洲EV-EVERY-每一，各EXCEPTN-EXCEPTION-除外EXCY-EXCELLENCY-阁下EXD-EXAMINED-检查过EX DIV-EX DIVIDEND-无红利EXP-EXPORT,EXPRESS,EXPENSES-出口，运送，费用EXS-EXPENSES-费用EXT-EXTRA-特别，额外F-FAHRENHEIT-华氏F/A/A;F.A.A.-FREE FROM ALL AVERAGE-分损不陪，全损赔偿F.A.Q.-FAIR AVERAGE QUALITY-大路货F.A.S.-FREE ALONGSIDE SHIP-船边交货价格F.B.-FREIGHT BILL-运费单FR-FRANC-法郎F.& D-FREIGHT AND DEMURRAGE-运费及滞期费F.E.-FOR EXAMPLE-例如FEB-FEBRUARY-二月F.G.A.-FREE FORM GENERAL AVERAGE-共同海损不赔F.I.-FOR INSTANCE-例如FIG-FIGURE-数字FIN STAT-FINANCIAL STATEMENT-财务报表FIN STNDG-FINANCIAL STANDING-资产状况FIN.YR.-FINANCIAL YEAR-会计年度F.I.T.-FREE OF INCOME TAX-免所得税FLWS;FLW-FOLLOWS,FOLLOW-如下FM-FROM-从F/O-IN FAVOR OF-支付给，以…为受益人的F.O.B-FREE ON BOARD-船上交货价F.O.C.-FREE ON CHARGE-免费F.O.I.-FREE OF INTEREST-免息F.O.R.-FREE ON RAIL-火车上交货价F.O.T.-FREE ON TRUCK-卡车上交货价FO.VO-FILIO VERSO = TURN THE PAGE-转下页F/P-FIRE POLICY-火灾保险单F.P.A.-FREE FROM PARTICULAR AVERAGE-平安险FR-FOR-为了FRI-FRIDAY-星期五FRNDLY-FREINDLY-友好的FRT-FREIGHT-运费FRT.PPD.-FREIGHT PREPAID-运费已付FT-FOOT,FEET-英尺FT.IN.-FEET AND INCHES-英尺与英寸FWD-FORWARO-前面，接下页F.X.-FOREIGN EXCHANGE-外汇G.A. G/A-GENERAL AVERAGE-共同海损GAL;GALL-GALLON-加仑GAS-GASOLINE-汽油GD-GOOD-好GDS-GOODS-货物G/N-GUARANTEE OF NOTES-承诺保证GM;GRM-GRAMME,GRAM-克GR-GROSS-罗，毛GR.WT.-GROSS WEIGHT-毛重A.AR.;AAR-AGAINST ALL RISKS-全险，综合险[/td] ABV-ABOVE-在...上面[/td]ABT-ABOUT-大约[/td]ABBR-ABBREVIATION-缩写[/td]ABS,STA-ABSTRACT,STATEMENT-摘要[/td]AC-ACRE-英亩[/td]ACCT-ACCOUNT;ACCOUNTANT-账户，会计师A/C;ACCT CURT-ACCOUNT CURRENT-账户，往来帐ACC-ACCEPTANCE;ACCEPTED-接受ACDG;ACDGLY-ACCORDING;ACCORDINGLY-按照，根据ACPTBLE-ACCEPTABLE-可接受的ACKGT;ACKMT-ACKNOWLEDGEMENT-承认，答谢，收贴ACPTC-ACCEPTANCE-接受，承兑ADJ-ADJUST-调节ADV-ADVISE-通知AD.;ADVT-ADVERTISEMENT-广告A.D.-ANNO DOMINI=SINCE THE BIRTH OF CHRIST-公元后A/D-AFTER DATE-发票后定期付款AD VAL-ACCORDING TO THE VALUE-按照价格ADMR-ADMINISTRATOR-财产管理人A.F.B.-AIR FREIGHT BILL-空运提单AFFT-AFFIDAVIT-宣誓书AFT-AFTER-之后AFTN-AFTERNOON-午后AGT-AGENT-代理ALTHO-ALTHOUGH-虽然ALWD-ALLOWED-允许AMB-AMBASSADOR-大使AMER;AMERN-AMERICAN-美国，美国的A.M.-ANTE MERIDIEM;BEFORE NOON-上午AMP-AMPERE-安培AMT-AMOUNT-金额ANS-ANSWER;ANSWERED-复出；回复A/O;ACC/O-ACCOUNT OF-入某账户A/OR-AND/OR-与/或A/P-AUTHORITY TO PURCHASE-委托购买证A.P.-ACCOUNT PAYABLE-应付账款APP-APPENDIX-附录APPROX-APPROXIMATELY-大约APL;APR-APRIL-四月A.R.;A/R-ALL RISKS;ACCOUNT RECEIVABLE-全险；应收帐户ARGE-ARRANGE-安排ARR-ARRIVAL-抵达ARVD-ARRIVED-到达ARRNG-ARRANGE-安排ARRT-ARRANGEMENT-安排ART-ARTICALE-物品，项目ASAP-AS SOON AS POSSIBLE-尽快A/S;ACC/S-ACCOUNT SALES-销货账单A/S-AFTER SIGHT-见票后ASS;ASSN-ASSOCIATION-联合，协会ASS'MT-ASSORTMENT-各色（物品）ASSIMT-ASSIGNMENT-分配，转让ASST-ASSISTANT-助理ASST-ASSISTANCE-援助，帮助ASSTD-ASSISTED-受援助的@-AT,TO,FROM-在，至，从ATT;ATTN;ATT'N-ATTENTION-注意ATTY-ATTORNEY-代理人，律师AUCT-AUCTION-拍卖AUG-AUGUST-八月AVE-AVENUE-大街AVLBL-AVAILABLE-可供的A.W.-ALL WOOL-纯毛A/W-ACTUAL WEIGHT-实际重量AWTG-AWAITING-等候BAL-BALANCE-余额BANKY-BANKRUPTCY-破产，倒闭BAR-BARREL-桶BRARGN-BARGAIN-讨价还价B.B-BACK-TO-BACK ACCOUNT-对开账户B/B-BILL BROUGHT-买入票据b.b-BEARER BOND-执票人债券B.C-BEFORE CHRIST,BILL FOR COLLECTION-公元前，托收票据BCOZ-BECAUSE-因为B.D.; b. d.-BILL DISCOUNTED,BANK DRAFT-贴现票据，银行票据b/d.-BROUGHT DOWN-接下页BDL-BUNDLE-捆，束BDTH-BREADTH-宽度B/E;B.EX-BILL OF EXCHANGE-汇票BEG-BEING-是B/F-BROUGHT FORWARD-承前页BF(R)-BEFORE-以前BG-BAG-袋BIZ-BUSINESS-业务，生意BK-BANK;BOOK-银行；书，帐薄BKG-BANKING-银行业务BKT-VASKET-篓，篮BKR-BANKER-银行家BL-BALE-包BLDG-BUILDING-建筑物，大厦B/L-BILL OF LADING-提单B/N;B,N.-BANK NOTE-钞票，纸币B.O.-BUYER'S OPTION,BRANCH OFFICE-买方选择权，分行B/O-BROUGHT OVER-结转BOT;BOTT-BOTTLE-瓶，罐B.P.;B/P-BILL PURCHASED-买入光票BR-BRAND-商标，牌B,BRIT-BRITISH,BRITAIN-英国的，英国B RGDS-BEST REGARDS-问候BRKGE-BROKERAGE-经纪费，佣金B.S.;B/S-BALANCE SHEET-资产负债表，借贷对照表B/S-BAGS,BALES-袋，包BTN-BETWEEN-之间bu. BUSH BSH-BUSHEL-蒲式耳C-CENTIGRADE-摄氏C-CENT-分CAPTND-CAPTIONED-标题项下的C/S CA;CAS;CS-CASES-箱C.A.C.-CREDIT ADVICE-收款报单C.A.D.-CASH AGAINST DOCUMENTS-付现交单C.A.F.-COST AND FREIGHT-运费在内（成本加）运费CAP-CAPTITAL-资本，资金CAPT;CPT-CAPTAIN-船长CAR-CARAT-克拉CARR.PD-CARRIAGE PAID-运费已付CASH-CASHIER-出纳员CAT-CATALOGUE-商品目录C.B.-CASH BOOK-现金帐簿C/B-CLEAN BILL-光票CB.FT.CBFT;CFT-CUBIC FEET-立方英尺C.B.D.-CASH BEFORE DELIVERY-付现后交货cu.cm.-CUBIC CENTIMETRE-立方厘米C.C-CARBON COPY-抄送某人CENT.-CENT,CENTRUM-百CERT.;CERTIF-CERTIFICATE;CERTIFIED-证明书，证明CF.;CFR.-CONFER-比较，协商C.F.&C.-COST,FREIGHT AND COMMISSION-运费佣金在内价(成本运费加佣金C.F.&I.-COST,FREIGHT AND INSURANCE-运费保险在内价(成本运费加保险价CFM-CONFIRM-确认CG-CENTIGRAMME-厘克C.H.-CLEARING HOUSE-票据交易所CHEQ-CHEQUE-支票CHGES-CHARGES-费用，税金CHT-CHEST-箱子，柜子C.I.-CERTIFICATE OF INSURANCE-保险单C&I-COST AND INSURANCE-保险费在内价（成本，加保险费）CIF-COST,INSURANCE,FREIGHT-保险运费在内价（成本，运费加保险费）C.I.F.&C-COST,INSURANCE,FREIGHT & COMMISSION-保险运费佣金在内价C.I.F.C.&I.-COST,INSURANCE,FREIGHT,COMMISSON & INTEREST-运费保险费佣金利息在内价C.I.F.&E-COST,INSURANCE,FREIGHT & EXCHANGE-运费保险汇费在内价一些常用的外贸英文缩写整理如下, 仅供各位参考.A组A.R：All Risks 一切险ANER 亚洲北美东行运费协定Asia North America Eastbound RateAWB: airway bill 空运提单ATTN：attentiona/c：account no.AWB：airway billB组B.D.I ：Both Days Inclusive 包括头尾两天BAF ：燃油附加费Bunker Adjustment FactorBAF ：燃油附加费，大多数航线都有，但标准不一。

GCV广义交叉验证

Plan
1 2
Generals What Regularization Parameter Examples Dening the Optimal
λ
is Optimal?
λ
3
Generalized Cross-Validation Cross Validation Generalized Cross Validation (GCV) Convergence Result
References
Spline models for Observational Data (1990) Grace Wahba Optimal Estimation of Contour Properties by Cross-Validated Regularization (1989) - Behzad Shahraray, David Anderson Smoothing Noisy Data with Spline Function (1979) - Peter Craven, Grace Wahba
l????????????????
Innehåll
Generals
What Regularization Parameter λ is Optimal?
Generalized Cross-Validation
Discussion
Generalized Cross Validation
Mårten Marcus
Plan
1 2
Generals What Regularization Parameter Examples Dening the Optimal
λ
is Optimal?
λ

ABAQUS帮助关键词总规则

*Contact：定义通用接触，只用于 explicit 中该选项表明通用接触定义的开始。每个 step 只能用一次，通用接触定义的变化可以通过下面的一些选项指定。可选参数： OP：设置 OP=MOD(默认)，更改已有的通用接触定义。设置 OP=NEW 删除以前定义的接触并定义新的。该选项没有数据行。
*BOUNDARY 节点编号或节点集，约定的边界条件类型 (这里的约定的边界条件类型包括： XSYMM：关于与 X 轴垂直的平面对称，即 U1=UR2=UR3=0； YSYMM：关于与 Y 轴垂直的平面对称，即 U2=UR1=UR3=0； ZSYMM：关于与 Z 轴垂直的平面对称，即 U3=UR1=UR2=0； XASYMM：关于与 X 轴垂直的平面反对称，即 U2=U3=UR1=0； YASYMM：关于与 Y 轴垂直的平面反对称，即 U1=U3=UR2=0； ZASYMM：关于与 Z 轴垂直的平面反对称，即 U1=U2=UR3=0； PINNED：约束所有平移自由度：即 U1=U2=U3=0； ENCASTRE：约束所有自由度(固定边界条件)，即 U1=U2=U3=UR1=UR2=UR3=0)
*Contact controls：为接触指定额外的控制该选项用来为接触模型提供额外的控制选项。标准的求解控制通常是足够的，但是额外的控制可以对解决复杂的几何和大量的接触对问题获得更高效的方法，同时也可以处理那些初始并未被约束的刚体运动。
*CONTACT CONTROLS 选项可以重复使用为不同的接触对设置不同的控制值，在 explicit 中必须与*CONTACT PAIR 联合使用。
ABAQUS 帮助里关键字（keywords）翻译总规则 1、关键字必须以*号开头，且关键字前无空格 2、**为注释行，它可以出现在文件中的任何地方 3、当关键字后带有参数时，关键词后必须采用逗号隔开 4、参数间都采用逗号隔开 5、关键词可以采用简写的方式，只要程序能识别就可以了 6、不需使用隔行符，如果参数比较多，一行放不下，可以另起一行，只要在上一行的末尾加逗号便可以

Why WFQ is not good enough for integrated services networks

Abstract
1 Introduction
Future integrated services networks 6, 8, 16] will support multiple services that include guaranteed realtime service, predicted real-time service, best-e ort service, and others. In addition, it needs to support link-sharing 9], which allows resource sharing among applications that require di erent network services but belong to the same administrative class. Consider the example shown in Figure 1 (a). There are 11 agencies or organizations sharing the same output link. The administrative policy dictates that Agency A1 gets at least 50% of the link bandwidth when the network is overloaded. In addition, to avoid the starvation of best-e ort tra c, from the 50% bandwidth assigned to A1, best-e ort tra c should get at least 20% bandwidth. It is important to design mechanisms to meet the goals of link sharing and requirements of di erent service classes simultaneously.