Conference on Computer Graphics and Interactive Techniques in Australasia and Southeast Asia最新文献

Backwards State-space Reduction for Planning in Dynamic Knowledge Bases 动态知识库中规划的向后状态空间约简

Conference on Computer Graphics and Interactive Techniques in Australasia and Southeast Asia Pub Date : 2014-07-29 DOI: 10.4204/EPTCS.159.8

V. Senni, M. Stawowy

{"title":"Backwards State-space Reduction for Planning in Dynamic Knowledge Bases","authors":"V. Senni, M. Stawowy","doi":"10.4204/EPTCS.159.8","DOIUrl":"https://doi.org/10.4204/EPTCS.159.8","url":null,"abstract":"In this paper we address the problem of planning in rich domains, where knowledge representation is a key aspect for managing the complexity and size of the planning domain. We follow the approach of Description Logic (DL) based Dynamic Knowledge Bases, where a state of the world is represented concisely by a (possibly changing) ABox and a (fixed) TBox containing the axioms, and actions that allow to change the content of the ABox. The plan goal is given in terms of satisfaction of a DL query. In this paper we start from a traditional forward planning algorithm and we propose a much more efficient variant by combining backward and forward search. In particular, we propose a Backward State-space Reduction technique that consists in two phases: first, an Abstract Planning Graph P is created by using the Abstract Backward Planning Algorithm (ABP), then the abstract planning graph P is instantiated into a corresponding planning graph P by using the Forward Plan Instantiation Algorithm (FPI). The advantage is that in the preliminary ABP phase we produce a symbolic plan that is a pattern to direct the search of the concrete plan. This can be seen as a kind of informed search where the preliminary backward phase is useful to discover properties of the state-space that can be used to direct the subsequent forward phase. We evaluate the effectiveness of our ABP+FPI algorithm in the reduction of the explored planning domain by comparing it to a standard forward planning algorithm and applying both of them to a concrete business case study.","PeriodicalId":360852,"journal":{"name":"Conference on Computer Graphics and Interactive Techniques in Australasia and Southeast Asia","volume":"113 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117251502","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Entity-Linking via Graph-Distance Minimization 通过图距离最小化实现实体链接

Conference on Computer Graphics and Interactive Techniques in Australasia and Southeast Asia Pub Date : 2014-07-29 DOI: 10.4204/EPTCS.159.4

Roi Blanco, P. Boldi, Andrea Marino

引用次数: 4

Specifying and Executing Optimizations for Parallel Programs 指定和执行并行程序的优化

Conference on Computer Graphics and Interactive Techniques in Australasia and Southeast Asia Pub Date : 2014-07-29 DOI: 10.4204/EPTCS.159.6

William Mansky, Dennis Griffith, E. Gunter

{"title":"Specifying and Executing Optimizations for Parallel Programs","authors":"William Mansky, Dennis Griffith, E. Gunter","doi":"10.4204/EPTCS.159.6","DOIUrl":"https://doi.org/10.4204/EPTCS.159.6","url":null,"abstract":"Compiler optimizations, usually expressed as rewrites on program graphs, are a core part of all modern compilers. However, even production compilers have bugs, and these bugs are difficult to detect and resolve. The problem only becomes more complex when compiling parallel programs; from the choice of graph representation to the possibility of race conditions, optimization designers have a range of factors to consider that do not appear when dealing with single-threaded programs. In this paper we present PTRANS, a domain-specific language for formal specification of compiler transformations, and describe its executable semantics. The fundamental approach of PTRANS is to describe program transformations as rewrites on control flow graphs with temporal logic side conditions. The syntax of PTRANS allows cleaner, more comprehensible specification of program optimizations; its executable semantics allows these specifications to act as prototypes for the optimizations themselves, so that candidate optimizations can be tested and refined before going on to include them in a compiler. We demonstrate the use of PTRANS to state, test, and refine the specification of a redundant store elimination optimization on parallel programs.","PeriodicalId":360852,"journal":{"name":"Conference on Computer Graphics and Interactive Techniques in Australasia and Southeast Asia","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133213037","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Graph Transformation Planning via Abstraction 通过抽象的图转换计划

Conference on Computer Graphics and Interactive Techniques in Australasia and Southeast Asia Pub Date : 2014-07-01 DOI: 10.4204/EPTCS.159.7

Steffen Ziegert

引用次数: 7

Strategic Port Graph Rewriting: An Interactive Modelling and Analysis Framework 战略港口图重写:一个交互式建模和分析框架

Conference on Computer Graphics and Interactive Techniques in Australasia and Southeast Asia Pub Date : 2014-04-05 DOI: 10.4204/EPTCS.159.3

M. Fernández, H. Kirchner, Bruno Pinaud

引用次数: 18

Generating and Solving Symbolic Parity Games 生成和解决符号奇偶游戏

Conference on Computer Graphics and Interactive Techniques in Australasia and Southeast Asia Pub Date : 2014-04-01 DOI: 10.4204/EPTCS.159.2

G. Kant, J. Pol

引用次数: 15

Graph- versus Vector-Based Analysis of a Consensus Protocol 基于图与向量的共识协议分析

Conference on Computer Graphics and Interactive Techniques in Australasia and Southeast Asia Pub Date : 2014-04-01 DOI: 10.4204/EPTCS.159.5

G. Delzanno, A. Rensink, Riccardo Traverso

引用次数: 3

Reachability in Cooperating Systems with Architectural Constraints is PSPACE-Complete 具有体系结构约束的协作系统中的可达性是pspace完备的

Conference on Computer Graphics and Interactive Techniques in Australasia and Southeast Asia Pub Date : 2013-12-01 DOI: 10.4204/EPTCS.138.1

M. Majster-Cederbaum, Nils Semmelrock

引用次数: 0

A Comparison of Sequential and GPU Implementations of Iterative Methods to Compute Reachability Probabilities 计算可达概率的迭代方法的顺序实现和GPU实现的比较

Conference on Computer Graphics and Interactive Techniques in Australasia and Southeast Asia Pub Date : 2012-10-23 DOI: 10.4204/EPTCS.99.5

Elise Cormie-Bowins

{"title":"A Comparison of Sequential and GPU Implementations of Iterative Methods to Compute Reachability Probabilities","authors":"Elise Cormie-Bowins","doi":"10.4204/EPTCS.99.5","DOIUrl":"https://doi.org/10.4204/EPTCS.99.5","url":null,"abstract":"We consider the problem of computing reachability probabilities: given a Markov chain, an initial state of the Markov chain, and a set of goal states of the Markov chain, what is the probability of reaching any of the goal states from the initial state? This problem can be reduced to solving a linear equation Ax = b for x, where A is a matrix and b is a vector. We consider two iterative methods to solve the linear equation: the Jacobi method and the biconjugate gradient stabilized (BiCGStab) method. For both methods, a sequential and a parallel version have been implemented. The parallel versions have been implemented on the compute unified device architecture (CUDA) so that they can be run on a NVIDIA graphics processing unit (GPU). From our experiments we conclude that as the size of the matrix increases, the CUDA implementations outperform the sequential implementations. Furthermore, the BiCGStab method performs better than the Jacobi method for dense matrices, whereas the Jacobi method does better for sparse ones. Since the reachability probabilities problem plays a key role in probabilistic model checking, we also compared the implementations for matrices obtained from a probabilistic model checker. Our experiments support the conjecture by Bosnacki et al. that the Jacobi method is superior to Krylov subspace methods, a class to which the BiCGStab method belongs, for probabilistic model checking.","PeriodicalId":360852,"journal":{"name":"Conference on Computer Graphics and Interactive Techniques in Australasia and Southeast Asia","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122191049","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 15

Efficient Instantiation of Parameterised Boolean Equation Systems to Parity Games 参数化布尔方程组对奇偶对策的有效实例化

Conference on Computer Graphics and Interactive Techniques in Australasia and Southeast Asia Pub Date : 2012-10-23 DOI: 10.4204/EPTCS.99.7

G. Kant, J. Pol

{"title":"Efficient Instantiation of Parameterised Boolean Equation Systems to Parity Games","authors":"G. Kant, J. Pol","doi":"10.4204/EPTCS.99.7","DOIUrl":"https://doi.org/10.4204/EPTCS.99.7","url":null,"abstract":"Parameterised Boolean Equation Systems (PBESs) are sequences of Boolean fixed point equations with data variables, used for, e.g., verification of modal mu-calculus formulae for process algebraic specifications with data. \u0000Solving a PBES is usually done by instantiation to a Parity Game and then solving the game. Practical game solvers exist, but the instantiation step is the bottleneck. \u0000We enhance the instantiation in two steps. First, we transform the PBES to a Parameterised Parity Game (PPG), a PBES with each equation either conjunctive or disjunctive. Then we use LTSmin, that offers transition caching, efficient storage of states and both distributed and symbolic state space generation, for generating the game graph. To that end we define a language module for LTSmin, consisting of an encoding of variables with parameters into state vectors, a grouped transition relation and a dependency matrix to indicate the dependencies between parts of the state vector and transition groups. \u0000Benchmarks on some large case studies, show that the method speeds up the instantiation significantly and decreases memory usage drastically.","PeriodicalId":360852,"journal":{"name":"Conference on Computer Graphics and Interactive Techniques in Australasia and Southeast Asia","volume":"111 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132731837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 15