Application servers are gaining popularity as a way for businesses to conduct day-to-day operations. Currently, the most adopted technologies for Application Servers are Java and .NET. While strong emphasis has been p...
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ISBN:
(纸本)3939352055
Application servers are gaining popularity as a way for businesses to conduct day-to-day operations. Currently, the most adopted technologies for Application Servers are Java and .NET. While strong emphasis has been placed on the performance and throughput of these servers, only a few research efforts have focused on the degradation behaviors. Specifically, investigating how they perform under stress and factors that affect their throughput degradation behaviors. As a preliminary study, we conducted experiments to observe the throughput degradation behavior of Java application servers and found that the throughput degrades ungracefully. thus, the goal of this work is three-fold: (i) identifying the primary factors that cause poor throughput degradation, (ii) investigating how these factors affect the throughput degradation, and (iii) observing how changes of algorithms and policies governing these factors affect the throughput degradation. Copyright 2006 ACM.
We first recall the concept of Kleene algebra with domain (KAD). then we explain how to use the operators of KAD to define a demonic refinement ordering and demonic operators (many of these definitions come from the l...
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As a distributed process calculus with localities and mobility of computational entities, Seal calculus is playing an important role in expressing key features such as security and mobility of Internet programming dir...
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ISBN:
(纸本)9780387446394
As a distributed process calculus with localities and mobility of computational entities, Seal calculus is playing an important role in expressing key features such as security and mobility of Internet programming directly. However, little implementation technique proposed for the calculus, partly due to the complication of inobile computation, which fusions three important techniques: concurrency, distribution and mobility at the same time. the abstract machine PSN for a distributed implementation of the Seal calculus is presented. In PSN the logical structure of a seal system and its physical distribution are separated which induces a more simple and clear implementation. Moreover, an operational semantics description of the Seal calculus based on PSN is given.
Testing Instruments are usually integrated into ATE (Automatic Testing Equipment) systems. A lot of factors should be taken into account, such as size, weight, cost, speed, modularity and interoperation and so on. So ...
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Although component-oriented thinking is quite common to software developers, the paradigm's impact beyond its "native" domain is limited. Financial engineering, a fast-growing discipline that combines fi...
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ISBN:
(纸本)3939352055
Although component-oriented thinking is quite common to software developers, the paradigm's impact beyond its "native" domain is limited. Financial engineering, a fast-growing discipline that combines finance, applied mathematics and computer science, often uses inflexible straightforward implementations for the underlying mathematical descriptions and models. Missing the benefits of modern software technology, even small variations in the financial products portfolio usually induce huge reimplementation efforts. Instead of concentrating on the creative aspects of contract development, financial engineers have to struggle with hard-to-modify implementations that decrease overall productivity. By providing concepts and techniques that improve and optimise the design and valuation methodology for derivative contracts, COMDECO1 transfers the principle of thinking in components to this discipline. Using an explorative composition style, problems caused by nearly unbounded flexibility, decreasing time to market periods and shortening product life cycles are tackled effectively. this paper introduces ACTIVE DOCUMENTS as the theoretical background constituting COMDECO's conceptual foundation. Reasons for the decision to base COMDECO's domain-specific framework on them and the resulting advantages are discussed. the current state of COMDECO's Java-based implementation is presented and potential next steps towards the goal of component-oriented financial engineering are sketched. Finally, possible future directions and novel scenarios of application for COMDECO's results are illustrated. Copyright 2006 ACM.
the lack of memory safety in many popular programming languages, including C and C++, has been a cause for great concern in the realm of software reliability, verification, and more recently, system security. A major ...
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ISBN:
(纸本)1595933700
the lack of memory safety in many popular programming languages, including C and C++, has been a cause for great concern in the realm of software reliability, verification, and more recently, system security. A major portion of known security attacks against software systems can be attributed to this shortcoming, including the well-known stack overflow, heap overflow, and format string attacks. Despite their limitations, the flexibility, performance, and ease of use of these languages have made them the choice of most embedded software developers. Researchers have proposed various techniques to enhance programs for memory safety;however, they are all subject to severe performance penalties, making their use impractical in most scenarios. In this paper, we present architectural enhancements to enable efficient, memory-safe execution of software on embedded processors. the key insight behind our approach is to extend embedded processors with hardware that significantly accelerates the execution of the additional computations involved in memory-safe execution. Specifically, we design custom instructions to perform various kinds of memory-safety checks and augment the instruction set of a state-of-the-art extensible processor (Xtensa from Tensilica, Inc.) to implement them. We demonstrate the application of the proposed architectural enhancements using CCured, an existing tool for type-safe retrofitting of C programs. the tool uses a type-inferencing engine that is built around strong type-safety theory and is provably safe. Simulations of memory-safe versions of popular embedded benchmarks on a cycle-accurate simulator modeling a typical embedded system configuration indicate an average performance improvement of 2.3x, and a maximum of 4.6x when using the proposed architecture. these enhancements entail minimal (less than 10%) hardware overhead to the base processor. Our approach is completely automated, and applicable to any C program, making it a promising and practi
Middleware for parallel and distributed systems is designed to virtualize computation and communication resources so that a more abstract and consistent view of those resources is presented to the applications that us...
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Middleware for parallel and distributed systems is designed to virtualize computation and communication resources so that a more abstract and consistent view of those resources is presented to the applications that use them. Providing such a consistent virtualization in distributed real-time and embedded systems becomes increasingly challenging due to application constraints such as timeliness and resource constraints such as CPU speed, power, memory, and bandwidth limitations, which also must be considered. this paper describes several examples of real-time CORBA middleware and examines how different constraints impact the way in which resources are virtualized in each case. Particular attention is paid to which details are hidden from users of the middleware, which details are exposed in the middleware's programming model, and how the hidden and exposed details interact to shape middleware design and implementation choices.
the proceedings contain 30 papers. the topics discussed include: object-oriented reengineering patterns - an overview;certifiable program generation;efficient code generation for a domain specific language;Bossa Nova:...
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ISBN:
(纸本)3540291385
the proceedings contain 30 papers. the topics discussed include: object-oriented reengineering patterns - an overview;certifiable program generation;efficient code generation for a domain specific language;Bossa Nova: introducing modularity into the Bossa domain-specific language;model compiler construction based on aspect-oriented mechanisms;shadow programming: reasoning about programs using Lexical join point information;generalized type-based disambiguation of meta programs with concrete object syntax;semi-inversion of guarded equations;a generative programming approach to interactive information retrieval: insights and experiences;and optimizing marshalling by run-time program generation.
A unified framework standing behind of a methodology aimed at object oriented decision support system design is considered. First of all the consistency of the assumed knowledge bases describing an object (enterprise)...
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A unified framework standing behind of a methodology aimed at object oriented decision support system design is considered. First of all the consistency of the assumed knowledge bases describing an object (enterprise) and requests (standard options supporting a decision maker), respectively are examined. then the knowledge base representation is transformed into representation of so called constraint satisfaction problem (CSP). Possible ways of the CSP decomposition as well as possibility of different programming languages application lead then to a problem aimed at searching for a distribution strategy allowing one to interact in an on-line mode.
Asset management involves the allocation of resources and capital in a supply chain such that the shareholder value is maximized. Supply chain redesign deals with investments, disinvestments and relocation of producti...
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Asset management involves the allocation of resources and capital in a supply chain such that the shareholder value is maximized. Supply chain redesign deals with investments, disinvestments and relocation of production facilities and distribution centers. Existing research has been focused on investments only. In this work, we present a novel mixed integer linear programming model that considers an end-to-end supply chain of a single multi-national corporation and address issues such as production allocation, material distribution, strategic material supply contracts, depreciation, and import-export regulatory factors, in addition to disinvestments.
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