As object-oriented paradigm becomes the mainstreamparadigm on software development, due to its attractivefeatures that can effectively divide a complex softwareproblem into several independent modules, one of theobjec...
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As object-oriented paradigm becomes the mainstreamparadigm on software development, due to its attractivefeatures that can effectively divide a complex softwareproblem into several independent modules, one of theobject-oriented languages - Java, becomes popular inrecent years because it is widely used in the rapidlygrowing Internet computing. However, similar to otherobject-oriented languages, Java has a big drawback of poorperformance. One of the main causes of the performance deficiencyis the extensive use of dynamic memory allocations anddeallocations during object or array creations anddestructions. Even a simple Othello applet game easilyrequires half a million of memory allocations for only onegame play. After analysis on the memory allocation behavior ofJava programs, it is concluded that about 99% of theallocations are of sizes less than 1024 bytes. The analysisalso shows that most of the allocated chunks in small sizewill survive only a very short period of time and after theyare garbage collected, they can be reused in the very nearfuture. This implies the memory allocation / deallocationpattern in Java is bounded to a certain kind of locality. The information presented in this paper is a referencefor designing an efficient hardware memory allocation /deallocation unit.
This paper addresses the problem of functionalverification starting from a high level description ofthe system under test, specified in SystemC. Theverification method considered is based upon thesimulation of executa...
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ISBN:
(纸本)0780379411
This paper addresses the problem of functionalverification starting from a high level description ofthe system under test, specified in SystemC. Theverification method considered is based upon thesimulation of executable SystemC description. Testcoverage analysis is the main technique for checkingand showing that the testing has been thorough. In thispaper we propose a novel approach to automate thecoverage analysis using Aspect-oriented *** here are described as checkers for detectingcoverage. The most important feature using theaspect-oriented technology here is that allowschecking functions across classes to be added orreplaced without modifying the original code. UML2.0is used to model the dynamic behavior view ofSystemC description as a coverage metric modelInherently it is possible to automate the whole testcoverage analysis using our methodology.
We present a novel approach to dynamic datarace detection for multithreaded object-oriented programs. Past techniques for on-the-fly datarace detection either sacrificed precision for performance, leading to many fals...
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ISBN:
(纸本)9781581134636
We present a novel approach to dynamic datarace detection for multithreaded object-oriented programs. Past techniques for on-the-fly datarace detection either sacrificed precision for performance, leading to many false positive datarace reports, or maintained precision but incurred significant overheads in the range of 3x to 30x. In contrast, our approach results in very few false positives and runtime overhead in the 13% to 42% range, making it both efficient and precise. This performance improvement is the result of a unique combination of complementary static and dynamic optimization techniques.
This paper presents a unified approach to building intelligent architectures. Our approach relies on making some semantic, ontological, os well os architectural commitments. Semantically, we commit ourselves to princi...
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This paper presents a unified approach to building intelligent architectures. Our approach relies on making some semantic, ontological, os well os architectural commitments. Semantically, we commit ourselves to principles governing the nature of the entities represented by the knowledge representation formalism, and the relationships between the faculties of reasoning, acting, and natural language understanding. More specifically, we concentrate on the nature and representation of entities, beliefs, actions, plans, and reasoning and acting rules. Based on these principles we present the design of an integrated AI architecture that has a unified knowledge representational formalism os well as a unified reasoning and acting component. The design of the architecture is based on object-oriented principles. We also show that such a design is amenable to implementation in a concurrent object-oriented programming paradigm. We demonstrate the advantages of our approach using several examples from our work.< >
The contribution of this paper is the first Hardware Transactional Memory (HTM) where the object structure is recognized and harnessed. Our approach is similar to hardware support of paged virtual memory using a virtu...
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ISBN:
(纸本)9781595939739
The contribution of this paper is the first Hardware Transactional Memory (HTM) where the object structure is recognized and harnessed. Our approach is similar to hardware support of paged virtual memory using a virtually addressed cache and a TLB, and is based on a cache hierarchy that allows the addressing of objects by unique object identifiers. The object-aware HTM allows cache overflows of uncommitted data. It also enables a novel commit and conflict detection mechanism. In this preliminary evaluation, the Lee-TM application exhibits overflows that in most previous HTMs would have had to be handled by software, impacting on performance. The simulation provides an insight into the scalability characteristics of the proposed HTM, which uses object and field granularity, lazy versioning and lazy conflict detection. For example, with 32 cores the broadcast of write sets is at under 5% of the bus bandwidth, showing the potential of object-aware HTM systems.
An invariant in the class is a predicate, which is true in every state that is proclaimed as valid, independently of what is considered to be a state. In addition, invariants themselves may be based on the behavior of...
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ISBN:
(纸本)9781457714993
An invariant in the class is a predicate, which is true in every state that is proclaimed as valid, independently of what is considered to be a state. In addition, invariants themselves may be based on the behavior of a particular object or a class as a whole. Analysis of invariants takes the most important place in object-oriented program verification and can be directed in two ways - as prescribed and as described. This paper considers as prescribed analysis which is based on strongest postconditions of methods with the guard as the precondition, thus, determining all reachable states and only them.
The Image Understanding Environment (IUE) project is a five year program, sponsored by ARPA, to develop a common object-oriented software environment for the development of algorithms and application systems. This pap...
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The Image Understanding Environment (IUE) project is a five year program, sponsored by ARPA, to develop a common object-oriented software environment for the development of algorithms and application systems. This paper reviews the design of this system and provides an overview of the distributed implementation effort currently underway at Amerinex AI, Advanced Decision Systems, Carnegie Mellon University, and Colorado State University. The ultimate goal of the project is to provide a software infrastructure of class hierarchies, user interface tools, and IU algorithms that are required to carry out state of the art research in image understanding.< >
We present the Program by Design introductory CS curriculum through the lenses of graphics, animations, algebra, and data structures. Animations programming is popular for CS1, but many such curricula lack clean paths...
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ISBN:
(纸本)9781450310987
We present the Program by Design introductory CS curriculum through the lenses of graphics, animations, algebra, and data structures. Animations programming is popular for CS1, but many such curricula lack clean paths into CS2. Program by Design is different. Using and reinforcing concepts from algebra, students learn to write animations (including standard topics such as model/view separation and event-handling), then move seamlessly into working with structured data, lists, trees, and objects. The curriculum emphasizes design, testing, and writing maintainable programs, without losing the engagement of animations. The workshop uses lectures and hands-on exercises to provide high- school and college teachers an overview of the approach. See ***. Laptop Optional.
A concurrent object-oriented programming (COOP) model is presented for computer-aided engineering using a blackboard architecture. The basic components of the model are a hierarchy of tasks, global and local controlle...
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In this paper, we describe an information technology capital budgeting (ITCB) problem, show that the ITCB problem can be modeled as a 0-1 knapsack optimization problem, and propose two different simulated annealing (S...
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