Since the introduction of the Java language less then a decade ago, there have been several attempts to create a runtime system for distributed execution of multithreaded Java applications. the goal of these attempts ...
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ISBN:
(纸本)0769521320
Since the introduction of the Java language less then a decade ago, there have been several attempts to create a runtime system for distributed execution of multithreaded Java applications. the goal of these attempts was to gain increased computational power while preserving Java's convenient parallel programming paradigm. this paper gives a detailed overview of the existing distributed runtime systems for Java and presents a new approach, implemented in a system called JavaSplit. Unlike previous works, which either forfeit Java's portability or introduce unconventional programming constructs, JavaSplit is able to execute standard multithreaded Java while preserving portability. JavaSplit works by rewriting the bytecodes of a given parallel application, transforming it into a distributed application that incorporates all the runtime logic. Each runtime node carries out its part of the resulting distributed computation using nothing but its local standard (unmodified) Java Virtual Machine (JVM).
We have developed a new magnet for open high field (0.7 T) MRI systems. In order to homogenize magnetic fields in the field of view, an optimization method to determine initial configurations of large correction iron ...
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We have developed a new magnet for open high field (0.7 T) MRI systems. In order to homogenize magnetic fields in the field of view, an optimization method to determine initial configurations of large correction iron pieces was developed. In our method, we combined linear programming (LP) and 3D magnetic FEA and, using analytic formulae for LP, we computed field harmonics due to the volume of magnetized iron.
In this paper we study the complexity of the model-checking problem for the tree logic introduced as the basis for the query language TQL [Cardelli and Ghelli, 2001]. We define two distinct fragments of this logic: TL...
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We describe the use of mobile agent technologies in building a framework for supporting distributed logicprogramming and remote conditional querying. A mobile agent moves from server to server carrying its own knowle...
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We describe the use of mobile agent technologies in building a framework for supporting distributed logicprogramming and remote conditional querying. A mobile agent moves from server to server carrying its own knowledge. When it arrives at a server it is given read access to the some part of the server's knowledge base. It then answers its queries using the server's knowledge and its own, adding the results to its own knowledge. We can view the mobile agent's queries as conditional remote queries - what answers would the server give if the knowledge carried by the agent were added to the server. To implement a prototype framework of mobile agents and knowledge servers we have used a new multiparadigm and multi-threaded programming language Go !. this supports mobile agent's as knowledge objects and has powerful knowledge structuring features. We assume some familiarity with Prolog.
Preference elicitation is a serious bottleneck in many decision support applications and agent specification tasks. Ceteris paribus (CP)-nets were designed to make the process of preference elicitation simpler and mor...
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Preference elicitation is a serious bottleneck in many decision support applications and agent specification tasks. Ceteris paribus (CP)-nets were designed to make the process of preference elicitation simpler and more intuitive for lay users by graphically structuring a set of CP preference statements-preference statements that most people find natural and intuitive. Beside their usefulness in the process of preference elicitation, CP-nets support efficient optimization algorithms that are crucial in most applications (e. g., the selection of the best action to execute or the best product configuration). In various contexts, CP-nets with an underlying cyclic structure emerge naturally. Often, they are inconsistent according to the current semantics, and the user is required to revise them. In this paper, we show how optimization queries can be meaningfully answered in many "inconsistent" networks without troubling the user with requests for revisions. In addition, we describe a method for focusing the user's revision process when revisions are truly needed. In the process, we provide a formal semantics that justifies our approach and new techniques for computing optimal outcomes. Some of the methods we use are based on a reduction to the problem of computing stable models for nonmonotonic logic programs, and we explore this relationship closely.
Content management is a confusing term used in several contexts. We define content management as the organizing of information (for a specific purpose) available in a system. We present the mixer method that uses serv...
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Content management is a confusing term used in several contexts. We define content management as the organizing of information (for a specific purpose) available in a system. We present the mixer method that uses servlet technology and the model-view-controller design pattern as a way to accomplish content management in a system. the heart of the mixer method is mixer which is a novel helper tool based on a template engine design philosophy. In order to validate our method we show how to solve the problem of separating Java code and HTML code in servlet programming. In our opinion the existing solutions are either too complex or not complete. the mixer method elegantly decouples the data access code, business logic code, and data presentation. Our work shows that the mixer method is easy to learn and to use. We have tested and used the mixer method successfully in large university courses dealing with content management and HTTP server side programming.
Summary form only given. Reconfigurable computing requires organizing computation with mixtures of processors and discrete logicthus presenting a difficult problem of hardware/software integration. An execution model...
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Summary form only given. Reconfigurable computing requires organizing computation with mixtures of processors and discrete logicthus presenting a difficult problem of hardware/software integration. An execution model and adaptation of functional programming is proposed which removes the distinction between hardware and software while offering the possibility of "correct by construction" design. the resulting language is called "V" because one way of creating it is to begin withthe verifiable, synthesizable subset of Verilog, and then add functional programming features. V generates the net-list of elementary functions which are supported by an array. the compiler has stages of compilation and instantiation so that recursion can be supported in the early definition of a design. the execution model is cycle based synchronous dataflow. V syntax looks much like Verilog or C without pointers in order to facilitate adoption.
We have developed a new magnet for open high field (0.7 T) MRI systems. Since MRI systems are installed in hospital sites, it is important to reduce stray magnetic fields of the magnets. We studied passive, active and...
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We have developed a new magnet for open high field (0.7 T) MRI systems. Since MRI systems are installed in hospital sites, it is important to reduce stray magnetic fields of the magnets. We studied passive, active and hybrid shielding methods and compared them. In order to study feasibility of active shielding, we considered higher order multipole stray fields. We present details of the calculation method and the results.
We introduce a new synchronization problem in mobile ad-hoc systems: the Driving Philosophers. In this problem, an unbounded number of driving philosophers (processes) access a round-about (set of shared resources org...
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ISBN:
(纸本)1402081405
We introduce a new synchronization problem in mobile ad-hoc systems: the Driving Philosophers. In this problem, an unbounded number of driving philosophers (processes) access a round-about (set of shared resources organized along a logical ring). the crux of the problem is to ensure, beside traditional mutual exclusion and starvation freedom at each particular resource, gridlock freedom (i.e., a cyclic waiting chain among processes). the problem captures explicitly the very notion of process mobility and the underlying model does not involve any assumption on the total number of (participating) processes or the use of shared memory, i.e., the model conveys the ad-hoc environment. We present a generic algorithm that solves the problem in a synchronous model. Instances of this algorithm can be fair but not concurrent, or concurrent but not fair. We derive the impossibility of achieving fairness and concurrency at the same time as well as the impossibility of solving the problem in an asynchronous model. We also conjecture the impossibility of solving the problem in an ad-hoc network model with limited-range communication.
the proceedings contain 50 papers. the special focus in this conference is on theoretical Computer Science. the topics include: Stability of approximation in discrete optimization;towards a broader theory of mobile pr...
ISBN:
(纸本)1402081405
the proceedings contain 50 papers. the special focus in this conference is on theoretical Computer Science. the topics include: Stability of approximation in discrete optimization;towards a broader theory of mobile processes;a decidable analysis of security protocols;looking inside AES and BES;remove key escrow from the identity-based encryption system;a randomised algorithm for checking the normality of cryptographic Boolean functions;reversible circuit realizations of Boolean functions;resource bounded immunity and simplicity;degree bounds on polynomials and relativization theory;the firing squad synchronization problem with many generals for one-dimensional CA;a matrix q-analogue of the Parikh map;the inherent queuing delay of parallel packet switches;efficient protocols for computing the optimal swap edges of a shortest path tree;truthful mechanisms for generalized utilitarian problems;the driving philosophers;engineering an external memory minimum spanning tree algorithm;scheduling with release times and deadlines on a minimum number of machines;approximation algorithms for mixed fractional packing and covering problems;on weighted rectangle packing with large resources;efficient algorithms for handling molecular weighted sequences;imperfectness of data for STS-based physical mapping;solving packing problem with weaker block solvers;adaptive sorting with AVL trees;prototyping proof carrying code;contract oriented development of component software;new insights on architectural connectors;on complexity of model-checking for the TQL logic;tailoring recursion to characterize non-deterministic complexity classes over arbitrary structures;a calculus with lazy module operators;dynamic typing with dependent types;subtyping-inheritance conflicts;asymptotic behaviors of type-2 algorithms and induced baire topologies;effective chemistry for synchrony and asynchrony;controller synthesis for probabilistic systems;highly undecidable questions for process algebras;a higher-or
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