The use of property classifications and patterns, i.e., high-level abstractions that describe common behavior have been shown to assist practitioners in generating formal specifications that can be used informal verif...
详细信息
ISBN:
(纸本)9780769530437
The use of property classifications and patterns, i.e., high-level abstractions that describe common behavior have been shown to assist practitioners in generating formal specifications that can be used informal verification techniques. The Specification Pattern System (SPS) provides descriptions of a collection of patterns. The extent of program execution over which a pattern must hold is described by the notion of scope. SPS provides a manual technique for obtaining formal specifications from a pattern and a scope. The Property Specification Tool (Prospec) extends SPS by introducing Composite Propositions (CPs), a classification for defining sequential and concurrent behavior to represent pattern and scope parameters, and provides a tool to support users. This work provides general templates for generating formal specifications in Linear Temporal Logic (LTL) for all pattern, scope, and CP combinations. In addition, the work explains the methodology for the verification of the correctness of these templates.
The Bowl Championship Series (BCS) is the system used to select the top two college football teams to play in a championship game at the end of a season. During the nine seasons played under the BCS, few have not caus...
详细信息
Publish/Subscribe model has become a prevalent paradigm for building distributed event delivering systems. Content-based publish/subscribe allows high expresses in subscriptions and thus is more appropriate for conten...
详细信息
software patch generation is a critical phase in the life-cycle of a software vulnerability. The longer it takes to generate a patch, the higher the risk a vulnerable system needs to take to avoid from being compromis...
详细信息
ISBN:
(纸本)1595935746
software patch generation is a critical phase in the life-cycle of a software vulnerability. The longer it takes to generate a patch, the higher the risk a vulnerable system needs to take to avoid from being compromised. However, in practice, it is a rather lengthy process to generate and release software patches. For example, the analysis on 10 recent Microsoft patches (MS06-045 to MS06-054) shows that, for an identified vulnerability, it took 75 days on average to generate and release the patch. In this paper, we present the design, implementation, and evaluation of AutoPaG, a system that aims at reducing the time needed for software patch generation. In our current work, we mainly focus on a common and serious type of software vulnerability: the out-of-bound vulnerability which includes buffer overflows and general boundary condition errors. Given a working out-of-bound exploit which may be previously unknown, AutoPaG is able to catch on the fly the out-of-bound violation, and then, based on data flow analysis, automatically analyzes the program source code and identifies the root cause - vulnerable source-level program statements. Furthermore, within seconds, AutoPaG generates a fine-grained source code patch to temporarily fix it without any human intervention. We have built a proof-of-concept system in Linux and the preliminary results are promising: AutoPaG is able to successfully identify the root cause and generate a source code patch within seconds for every vulnerability test in the Wilander's buffer overflow benchmark test-suite. In addition, the evaluation with a number of real-world out-of-bound exploits also demonstrates its effectiveness and practicality in automatically identifying (vulnerable) source code root causes and generating corresponding patches. Copyright 2007 ACM.
This paper presents a cross-modal approach of image retrieval from a medical image collection which integrates visual information based on purely low-level image contents and case related textual information from the ...
详细信息
Developer mailing lists are a rich source of information about Open Source software (OSS) development. The unstructured nature of email makes extracting information difficult. We use a psychometrically-based linguisti...
详细信息
Java has recently joined C and C++ as a relatively high-level language suitable for developing real-time applications. Java's garbage collection, while generally a useful feature, can be problematic for real-time ...
详细信息
Block motion estimation with full search is computationally complex. To reduce this complexity, different methods have been proposed, including partial distortion, which can reduce the computational complexity with no...
详细信息
ISBN:
(纸本)9781424410163
Block motion estimation with full search is computationally complex. To reduce this complexity, different methods have been proposed, including partial distortion, which can reduce the computational complexity with no loss of image quality. We propose a distortion-based partial distortion search (DPDS) based on the magnitude of distortion and adaptive update of the matching order. We calculate absolute differences for all pixels in the predicted block point. Pixels are then sorted by the amount of distortion in a descending order for the matching process, which produces a scanning map. The sum of the absolute differences (SAD) of other candidate positions is then computed from this matching order. We also use an update of the scanning map by checking the increase in the number of absolute differences for the SAD value. The proposed DPDS algorithm improves the computational efficiency, compared with the original PDS scheme, because the accumulated value of the absolute pixel differences can rapidly reach the current minimum SAD value. The proposed algorithm is 4-13 times faster than the full search method with the same visual quality.
The availability of multiple rates in IEEE8O2. 11 WLANs and instability of wireless channel conditions call for data rate adaption algorithms to optimize network performance. Rate adaption is the process of assessing ...
详细信息
The availability of multiple rates in IEEE8O2. 11 WLANs and instability of wireless channel conditions call for data rate adaption algorithms to optimize network performance. Rate adaption is the process of assessing instantaneous channel conditions and determining the most appropriate data rate. This paper presents a relaxed probing rate adaptation scheme to determine the most appropriate instantaneous data rate for both downlink and uplink channels, especially in the case where control frames such as RTSICTS are not available. For this goal, the proposed scheme exploits the mandatory management beacon frame, thus without requiring probing frames like RTS/CTS necessary for other so far proposed schemes. Ns-2 simulations with IEEE8O2. 1 lb of the proposed scheme yield more than 100% throughput improvement in high density networks. Also, simulations show that the proposed scheme is insensitive to beacon interval.
In order to improve personal data security in the electronic commerce, and to avoid information exposing of personal privacy, personal data was used as the encrypted principle, applying homomorphism and random perturb...
详细信息
暂无评论