An attack knowledge model that can be applied in the initiative defense architecture is proposed, and the model's practicability, re-useability and extendibility are achieved. The attack knowledge is described usi...
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An attack knowledge model that can be applied in the initiative defense architecture is proposed, and the model's practicability, re-useability and extendibility are achieved. The attack knowledge is described using attack knowledge description language (AKDL), and the data, operations and relations of attacks are modeled based on object-oriented technology. An AKDL to C++ comp.ler is used to comp.le the attack knowledge in AKDL language into C++ source code of attack comp.nent object, then the attack knowledge library (AKL) is implemented, which can provide the attack knowledge to the various security modules through APIs.
Implementation of a real time stereo vision system for obstacle detection and localization is discussed for planetary rover. The system employs binocular or trinocular stereo with fish-eye lenses to capture stereo pai...
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Implementation of a real time stereo vision system for obstacle detection and localization is discussed for planetary rover. The system employs binocular or trinocular stereo with fish-eye lenses to capture stereo pairs with a very large field of view (FOV-160°). Camera calibration parameters are used to perform distorted image correction, epipolar rectification and LoG filtering, and the SAD similarity is comp.ted to estimate dense depth maps under the epipolar and smooth constraints. Using the Intel MMX inst.uction set and LUT, the system can comp.ete dense depth mapping and obstacle detection in real time. The test result shows that the system can produce dense depth maps at 10 Hz with a resolution of 320×120 pixels and a disparity of 64 levels using standard PCs, are allow the robot to safely travel at 1m/s.
Aiming at the requirements specification and related checking of embedded real-time software, a visual modeling language, RTRSM* (real-time requirements specification model*), which is comp.sitional and based on hiera...
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Aiming at the requirements specification and related checking of embedded real-time software, a visual modeling language, RTRSM* (real-time requirements specification model*), which is comp.sitional and based on hierarchical and concurrent finite state machine, is proposed. It uses state transitions with duration and scheduled events to describe timing constraints, and can support the description of interactivity and timing constraints effectively. Additionally, RITL (real-time interval temporal logic), a kind of prepositional temporal logic, is presented to make up for RTRSM*'s defect description of global system properties, which is the drawback of operational specification languages. Interpreted over timed state sequences, RITL is able to deal with the description of both point-based and interval-based metric temporal properties, and supports the property description of RTRSM* models naturally and comp.ehensively. The verification and validation of the resulted requirements specification, especially issues with respect to the reachability graph of RTRSM* models with finite system states and the simulation execution of the specification, are also explored.
Normalization design of XML Schemata and DTDs (document type definitions) is to produce a set of XML schemata or DTDs that can well represent data dependencies and eliminate redundancies. Now there are a few researche...
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Normalization design of XML Schemata and DTDs (document type definitions) is to produce a set of XML schemata or DTDs that can well represent data dependencies and eliminate redundancies. Now there are a few researches on it, and the existing researches are still at its initial stage. Provost proposed the idea of applying the theory of relational database to XML schemata normalization design. This idea has not been put into practice. The paper shows algorithms of hierarchical schemata design for XML schemata and DTDs normalization design based on Provost's idea. Firstly the paper analyzes hierarchy decomp.sition based on Provost's idea. Then it presents an algorithm producing a decomp.sition tree to eliminate redundant schemata. Finally it shows an algorithm of hierarchical schemata design for XML schemata and DTDs normalization design to get over deficiencies for Provost's idea. With respect to other researches on normalization design for XML schemata and DTDs, the set of full and embedded MVDs in hierarchical schemata produced by these algorithms are implied by the given set of MVDs (multivalued dependencies), and the hierarchical schemata eliminate redundant ones and satisfy the lossless join property.
Formal verification is in effect to detect security protocols. The development of BAN-like logics promotes the research of this area. At the same time, there are many problems with current BAN-like logics. Based on an...
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Formal verification is in effect to detect security protocols. The development of BAN-like logics promotes the research of this area. At the same time, there are many problems with current BAN-like logics. Based on analyzing these BAN-like logics, a new formal verification method of security protocols is presented. The new logic can realize verification function of current BAN-like logics, and makes the verification process implement conveniently. Consequently verification can be realized automatically. This logic gives a new approach to the formal verification of security protocols.
In this paper, a new hybrid impulsive and switching control strategy for chaos synchronization is developed. Using switched Lyapunov functions, several new criteria for exponential stability and asymptotical stability...
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ISBN:
(纸本)0780388739
In this paper, a new hybrid impulsive and switching control strategy for chaos synchronization is developed. Using switched Lyapunov functions, several new criteria for exponential stability and asymptotical stability of hybrid impulsive and switching nonlinear systems are established and, particularly, some simple sufficient conditions for driving the synchronization error to zero are proposed. A typical example, the Chua's chaotic circuit, is given for illustrating and visualizing the theoretical results.
Large-scale systems like BlueGene/L are susceptible to a number of software and hardware failures that can affect system performance. In this paper evaluate the effectiveness of a previously developed job scheduling a...
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ISBN:
(纸本)0769521320
Large-scale systems like BlueGene/L are susceptible to a number of software and hardware failures that can affect system performance. In this paper evaluate the effectiveness of a previously developed job scheduling algorithm for BlueGene/L in the presence of faults. We have developed two new job-scheduling algorithms considering failures while scheduling the jobs. We have also evaluated the impact of these algorithms on average bounded slowdown, overage response time and system utilization, considering different levels of proactive failure prediction and prevention techniques reported in the literature. Our simulation studies show that the use of these new algorithms with even trivial fault prediction confidence or accuracy levels (as low as 10%) can significantly improve the performance of the BlueGene/L system.
By displaying Web usage and structure information on the Web structure maps and selecting appropriate data sources, a site usability analysis tool (SUAT) is proposed based on the two-dimension visualization technology...
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By displaying Web usage and structure information on the Web structure maps and selecting appropriate data sources, a site usability analysis tool (SUAT) is proposed based on the two-dimension visualization technology. This tool can help site analysts to discover the usage pattern of Web visitors and the usability problems existing in a website. By the analysis of a practical case, it is proved that the two-dimension visualization technology is effective for the analysis of website usability and can greatly help website designers simplify the process of improving the content and structure of the website.
With the exponential growth of both the amount and the diversity of the web information, web site mining is highly desirable for automatically discovering and classifying topic-specific web resources from the World Wi...
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With the exponential growth of both the amount and the diversity of the web information, web site mining is highly desirable for automatically discovering and classifying topic-specific web resources from the World Wide Web. Nevertheless, existing web site mining methods have not yet handled adequately how to make use of all the correlative contextual semantic clues and how to denoise the content of web sites effectually so as to obtain a better classification accuracy. This paper circumstantiates three issues to be solved for designing an effective and efficient web site mining algorithm, i.e., the sampling size, the analysis granularity, and the representation structure of web sites. On the basis, this paper proposes a novel multiscale tree representation model of web sites, and presents a multiscale web site mining approach that contains an HMT -based two-phase classification algorithm, a context-based interscale fusion algorithm, a two-stage text-based denoising procedure, and an entropy-based pruning strategy. The proposed model and algorithms may be used as a starting -point for further investigating some related issues of web sites, such as query optimization of multiple sites and web usage mining. Experiments also show that the approach achieves in average 16% improvement in classification accuracy and 34.5% reduction in processing time over the baseline system.
The design of a parallel debugger is indispensable and yet still challenging in developing tools for parallel environments. This paper focuses on the design and implementation of an actual parallel debugger, DCDB3.0 (...
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The design of a parallel debugger is indispensable and yet still challenging in developing tools for parallel environments. This paper focuses on the design and implementation of an actual parallel debugger, DCDB3.0 (Dawning Cluster DeBugger), which has been realized on Dawning 3000 clusters as a part of the cluster operating system to be used on Dawning 4000. DCDB3.0 is of a typical client/server structure. A friendly user interface is provided, which visualizes the tedious process of debugging. The user interfaces, as clients, can be distributed far away from the server with the aid of DRPC (Dawning remote procedure call), which provides communications between the client end and the server end, and with the aid of the task management module, which makes it easy for the client end to execute programs on the server machine. Both DRPC and task management module, like DCDB3.0, are parts of the cluster operating system. The server end of DCDB3.0 deals with debugging processes, receiving debugging commands and sending results. The scalability of DCDB3.0 is emphasized, which means that advanced parallel debugging techniques can be added. Replay based on recording wildcard message senders are implemented and DSM debugging and other techniques are going to be realized. comp.red with the former versions, DCDB3.0 is more powerful and convenient to users.
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