Building highly available enterprise applications using Web-oriented middleware is hard. Runtime implementations frequently do not address the problems of application state persistence and fault-tolerance, placing the...
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Building highly available enterprise applications using Web-oriented middleware is hard. Runtime implementations frequently do not address the problems of application state persistence and fault-tolerance, placing the burden of managing session state and, in particular, handling system failures on application programmers. This paper describes Phoenix/APP, a runtime service based on the notion of recovery guarantees. Phoenix/APP transparently masks failures and automatically recovers component-based applications. This both increases application availability and simplifies application development. We demonstrate the feasibility of this approach by describing the design and implementation of Phoenix/APP in Microsoft's .NET runtime and present results on the cost of persisting and recovering component-based applications.
Summary form only given. This tutorial surveys the state of the art in type systems for programming languages, focusing on the achievements and changes in emphasis during the past decade. The first part of the talk co...
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Summary form only given. This tutorial surveys the state of the art in type systems for programming languages, focusing on the achievements and changes in emphasis during the past decade. The first part of the talk considers the trajectory of work on object types, one of the major hot topics of the early and mid-'90s. Following some fundamental conceptual breakthroughs, the focus of attention in this area has shifted from foundational research to applications to the development and analysis of real-world language designs. The next part outlines recent progress on a number of "bread and butter" type systems topics and their applications in new programming languages: subtyping, polymorphism, type inference, effect systems, dependent types, and type systems for modular programming. The final section introduces some newer topics that have emerged (or gained unexpected prominence) in the past few years, including type systems for concurrent and distributed languages, high-level type systems for low-level languages such as assembly and C, substructural type systems based on linear logic and its relatives, modal type systems, the burgeoning area of language-based security, and native language support for statistically typed XML processing.
Pointers are an important programming concept. They are used explicitly or implicitly in many programming languages. In particular, the semantics of object-oriented programming languages rely on pointers. We introduce...
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Pointers are an important programming concept. They are used explicitly or implicitly in many programming languages. In particular, the semantics of object-oriented programming languages rely on pointers. We introduce a semantics for pointer structures. Pointers are seen as indexes and pointer fields are functions from these indexes to values. Using this semantics we turn all pointer operations into simple assignments and then we use refinement calculus techniques to construct a pointer-manipulating program that checks whether or not a single linked list has a loop. We also introduce an induction principle on pointer structures in order to reduce complexity of the proofs.
In this paper we present novel recharged logic for multiple-valued (MV) systems by utilizing semi-floating-gate (SFG) transistors. The recharged multiple-valued logic can be used to implement low-power digital circuit...
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In this paper we present novel recharged logic for multiple-valued (MV) systems by utilizing semi-floating-gate (SFG) transistors. The recharged multiple-valued logic can be used to implement low-power digital circuits. The improvement in power dissipation is mainly in reduced dynamic power dissipation. The main purpose is to level out the power dissipated by a digital system to obtain more suitable logic for mixed mode design.
The tasks of software development have traditionally been done by highly-skilled and well-trained computer programmers. A solid educational background is often required to understand programming languages used in the ...
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ISBN:
(纸本)0780382250
The tasks of software development have traditionally been done by highly-skilled and well-trained computer programmers. A solid educational background is often required to understand programming languages used in the development. For people who are educationally disadvantaged, the task of computer programming seems remote. It might appear that there is no strong reason for those people to partake programming activities. However, in today's volatile business environment, giving programming capabilities to the educationally disadvantaged might be an economically viable way to upgrade the competitiveness of a business entity. To achieve this, there is a need for an easy-to-use programming environment that has the following assumptions for its users: i) no formal trainings in computer programming, ii) minimum educational backgrounds, and iii) of different ethnicity and are unable to communicate using the commonly spoken language.
A modified Flash-EEPROM device is presented. This device operates as a non-volatile programmable pass transistor. Program and erase, operations are performed on a Flash-EEPROM cell coupled to a pass-transistor. Writte...
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A modified Flash-EEPROM device is presented. This device operates as a non-volatile programmable pass transistor. Program and erase, operations are performed on a Flash-EEPROM cell coupled to a pass-transistor. Written and erased states of the flash cell correspond to the open and close states of the pass-transistor respectively. The Flash-programmable pass transistor (FPT) was developed for multi-context programmable-logic, and it was realized in a technology for embedded Flash-EEPROM NOR memory. No additional process steps are required. This novel device has the same program and erasing behavior as the standard Flash-EEPROM cell, measurements are reported for a 0.18 /spl mu/m technology implementation.
Iwaki Meisei University, a popular university in Japan, has developed e-Learning oriented programming Courseware for freshmen using the authoring tool Hiplus, Hitachi Ltd., Japan, at the Department of Electronics and ...
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Iwaki Meisei University, a popular university in Japan, has developed e-Learning oriented programming Courseware for freshmen using the authoring tool Hiplus, Hitachi Ltd., Japan, at the Department of Electronics and Computer Science. Department freshmen are required to use this programming Courseware. This courseware consists of two parts: specification of requirement and verification of program validity. Both parts address the need for support by logical thinking in addition to production of software documents by a natural language. Using it, a modern programmer can use a dedicated algorithm which handles a newly developed object once a software requirement has been formally specified Moreover freshmen are able to assess their own learning progress due to graded exercises configured in the programming Courseware.
XML is designed to structure data for exchange. It is also a new trend to use XML to encode knowledge on the Web. An important project for this purpose is the semantic Web of W3C. They proposed several specifications,...
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ISBN:
(纸本)0780377249
XML is designed to structure data for exchange. It is also a new trend to use XML to encode knowledge on the Web. An important project for this purpose is the semantic Web of W3C. They proposed several specifications, including RDF/RDFS and OWL, for knowledge representation. In the architecture of SW, they proposed XML for the syntax layer, RDF/RDFS for the semantics layer, and OWL for the ontology layer. However, languages for the logic layer and proof layer are not yet defined. We propose a different approach for knowledge representation and reasoning. We define a logic-based framework to transform XML documents into logical facts, and to reason about these facts. The transforming and reasoning processes are based on a logic programming language, path inference language (PIL), which is specifically designed for tree-structure documents like XML. People may write a PIL program to extract logical facts from XML documents, and the extracted logical facts are imported into a logic-based ontology in PIL for reasoning. Based on PIL, we intend to develop a simple and powerful framework for people to interpret the semantics of XML easily.
In todays deep-submicron designs, the interconnect delays contribute an increasing part to the overall performance of an implementation. Particularly when targeting field programmable gate arrays (FPGAs), interconnect...
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In todays deep-submicron designs, the interconnect delays contribute an increasing part to the overall performance of an implementation. Particularly when targeting field programmable gate arrays (FPGAs), interconnect delays are crucial, since they can easily vary by orders of magnitude. Many existing performance-directed retiming methods use simple delay models which either neglect routing delays or use inaccurate delay estimations. In this paper, we propose a retiming approach which overcomes the problem of inaccurate delay models. Our retiming technique uses delay information extracted from a fully placed and routed design and takes account of register timing requirements. By applying physical constraints, we ensure that the delay information remains valid during retiming. In our experiments, we achieved up to 27% performance improvement.
The paper describes a methodological framework that aims to apply formal design and verification techniques to the domain of logic control and supervision for manufacturing systems. The methodology is based on an obje...
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The paper describes a methodological framework that aims to apply formal design and verification techniques to the domain of logic control and supervision for manufacturing systems. The methodology is based on an object-oriented approach, supported by a syntactical and semantical adaptation of the semi-formal software specification languages UML and statecharts. The modeling languages have been subsequently formalized, according to a semantics that take into account the concepts described in the IEC 61131-3 standard for industrial controllers programming, in order to prove correctness properties expressed in the temporal logic CTL. The verification process is performed by means of the model-checking tool SMV.
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