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991.
Geri Georg Indrakshi Ray Kyriakos Anastasakis Behzad Bordbar Manachai Toahchoodee Siv Hilde Houmb 《Information and Software Technology》2009,51(5):846-864
We propose a methodology, based on aspect-oriented modeling (AOM), for incorporating security mechanisms in an application. The functionality of the application is described using the primary model and the attacks are specified using aspects. The attack aspect is composed with the primary model to obtain the misuse model. The misuse model describes how much the application can be compromised. If the results are unacceptable, then some security mechanism must be incorporated into the application. The security mechanism, modeled as security aspect, is composed with the primary model to obtain the security-treated model. The security-treated model is analyzed to give assurance that it is resilient to the attack. 相似文献
992.
In Trusted Network Connect (TNC), a network access decision is based on the security state of an access requesting party. This mechanism is limited to closed environments such as LANs and VPNs. In this paper, we propose solutions based on authentication standards for enabling TNC in open, web-based scenarios. In particular, an architectural model for TNC is proposed that takes additional security and privacy requirements into account. Furthermore, a communication scheme is proposed that is based on standardised protocols and message formats. This approach provides assurance as to the security state of clients accessing security sensitive web-based services. 相似文献
993.
With a plethora of models, systems and standards to choose for a basis of software process improvement, decisions on which
to adopt may depend on a number of factors. This paper presents an evolutionary and extremely cost effective approach to implementing
a software quality system that requires minimum resource and little disruption to programme delivery. The method presented,
achieved a 40% improvement in the level of implementation of the AWE plc software quality management system over a 5-year
period. A critical success factor is the treatment of the users’ of the defined software quality system as customers, understanding
their concerns and problems, and being responsive to them. The importance of a well designed system is highlighted together
with the essential and extensive consultation process required to gain buy-in and lay the foundation for cultural change.
This was supported with a helpful programme of facilitated self-assessment and sustained by a closely aligned training scheme.
As a consequence some of the cultural elements were changed from one of thoughtless “tick-in-the-box” compliance to one of
true understanding of the system requirements, true quality implementation, and subsequent added value.
Michael Elliott is a Chartered Engineer and member of the British Computer Society. He is the Sodftware Quality Manager at the Atomic Weapons Establishment (AWE) in the UK and is accountable to ensure the certification to ISO 9001:2000 for all software related activities. Mike’s particular interest is the intricacies of dealing with different people in a culturally diverse establishment, such as AWE. He has recently completed post graduate research at Loughborough University with Ray Dawson and Janet Edwards. His thesis was entitled “Achieving business excellence in software quality management”. The research investigated the practical nuances of the internal auditing, the adoption of self-assessment as a methodology, the cost effectiveness of training and the cost-benefits associated with implementing best practice in software quality management. Ray Dawson obtained a Bachelor’s degree in mathematics with engineering and a masters degree in engineering from Nottingham University before entering industry with Plessey Telecommunications in 1977. While working at the company he developed an interest in the working methods for software development as practiced in industry. This became a research interest when he joined Loughborough University as a lecturer in 1987. Other research interests are information systems and knowledge management which he now combines with his interest in industrial working practices to work with companies to improve their information and knowledge management systems. Ray Dawson is now a Senior Lecturer in the Department of Computer Science and leader of the Knowledge Management Research Group at Loughborough University in the UK, and is a Chartered Engineer and fellow of the British Computer Society. Janet Edwards has recently retired as a lecturer in Computer Science at Loughborough University. She has a Btech (Hons) degree in Metallurgical Engineering and Management and an MSc degree by research in Robotic Control from Loughborough University. She spent a number of years working as a software engineer in various organisations before returning to Loughborough. Her current research interests include Electronic Communication and E-commerce. 相似文献
Janet EdwardsEmail: |
Michael Elliott is a Chartered Engineer and member of the British Computer Society. He is the Sodftware Quality Manager at the Atomic Weapons Establishment (AWE) in the UK and is accountable to ensure the certification to ISO 9001:2000 for all software related activities. Mike’s particular interest is the intricacies of dealing with different people in a culturally diverse establishment, such as AWE. He has recently completed post graduate research at Loughborough University with Ray Dawson and Janet Edwards. His thesis was entitled “Achieving business excellence in software quality management”. The research investigated the practical nuances of the internal auditing, the adoption of self-assessment as a methodology, the cost effectiveness of training and the cost-benefits associated with implementing best practice in software quality management. Ray Dawson obtained a Bachelor’s degree in mathematics with engineering and a masters degree in engineering from Nottingham University before entering industry with Plessey Telecommunications in 1977. While working at the company he developed an interest in the working methods for software development as practiced in industry. This became a research interest when he joined Loughborough University as a lecturer in 1987. Other research interests are information systems and knowledge management which he now combines with his interest in industrial working practices to work with companies to improve their information and knowledge management systems. Ray Dawson is now a Senior Lecturer in the Department of Computer Science and leader of the Knowledge Management Research Group at Loughborough University in the UK, and is a Chartered Engineer and fellow of the British Computer Society. Janet Edwards has recently retired as a lecturer in Computer Science at Loughborough University. She has a Btech (Hons) degree in Metallurgical Engineering and Management and an MSc degree by research in Robotic Control from Loughborough University. She spent a number of years working as a software engineer in various organisations before returning to Loughborough. Her current research interests include Electronic Communication and E-commerce. 相似文献
994.
We show how to compute Hong’s bound for the absolute positiveness of a polynomial in d variables with maximum degree δ in O(nlogdn) time, where n is the number of non-zero coefficients. For the univariate case, we give a linear time algorithm. As a consequence, the time bounds for the continued fraction algorithm for real root isolation improve by a factor of δ. 相似文献
995.
This article proposes a new method of 2D curve interpolation using non-uniform cubic B-splines particularly adapted to the interpolation of sequences of straight lines and circle arcs. The purpose of this method is to calculate C2 continuous curves adapted to high feedrate pocket machining. Industrially machined pockets usually present simple forms. Generally, the tool path is defined by circle arcs and line segments that introduce slowdowns during machining. Thus, a method for approximating a sequence of line segments and circle arcs using Bspline curves is proposed. The proposed method ensures exact line interpolation, to approach the tool path precisely, to reduce the number of control points and to avoid thickening and oscillation at the connections between line segments and circle arcs. Various applications are presented and numerous tests on machine tools allow the advantages of this method to be illustrated. 相似文献
996.
Evaluation of hyperspectral indices for LAI estimation and discrimination of potato crop under different irrigation treatments 总被引:1,自引:0,他引:1
S. S. Ray G. Das J. P. Singh S. Panigrahy 《International journal of remote sensing》2013,34(24):5373-5387
In this study, various hyperspectral indices were evaluated for estimation of leaf area index (LAI) and crop discrimination under different irrigation treatments. The study was conducted for potato crop using the spectral reflectance values measured by a hand‐held spectro‐radiometer. Three categories of hyperspectral indices, such as ratio/difference indices, multivariate indices and derivative based indices were computed. It was found that, among various band combinations for NDVI (normalized difference vegetation index) and SAVI (soil adjusted vegetation index), the band combination of the 780~680, produced highest correlation coefficient with LAI. Among all the forms of LAI and VI empirical relationships, the power and exponential equations had highest R 2 and F values. Analysis of variance showed that, hyperspectral indices were found to be more efficient than the LAI to detect the differences among crops under different irrigation treatments. The discriminant analysis produced a set of five most optimum bands to discriminate the crops under three irrigation treatments. 相似文献
997.
Rohit Chatterjee Mayukh Ghosh Ananda S. Chowdhury Nilanjan Ray 《Computer methods and programs in biomedicine》2013
Automated visual tracking of cells from video microscopy has many important biomedical applications. In this paper, we track human monocyte cells in a fluorescent microscopic video using matching and linking of bipartite graphs. Tracking of cells over a pair of frames is modeled as a maximum cardinality minimum weight matching problem for a bipartite graph with a novel cost function. The tracking results are further refined using a rank-based filtering mechanism. Linking of cell trajectories over different frames are achieved through composition of bipartite matches. The proposed solution does not require any explicit motion model, is highly scalable, and, can effectively handle the entry and exit of cells. Our tracking accuracy of (97.97 ± 0.94)% is superior than several existing methods [(95.66 ± 2.39)% [11], (94.42 ± 2.08)% [20], (81.22 ± 5.75)% [13], (78.31 ± 4.70)% [14]] and is highly comparable (98.20 ± 1.22)% to a recently published algorithm [26]. 相似文献
998.
Repeated use of reverse auction often degrades the buyer–supplier relationship. Theoretical studies show that providing incentive to the losing but competing suppliers can keep them interested to participate in future auctions thereby maintaining a healthy level of competition. We conduct web-based experiments to validate this theoretical observation in multi-attribute reverse auctions. We compare incentive-oriented and standard multi-attribute reverse auctions and demonstrate that the results in the laboratory setting corroborate the theoretical findings. Adopting incentive-oriented mechanism, the buyer is able to provide better utility to suppliers while protecting her own. We conclude that such a mechanism can reduce the negative perception of the suppliers and help build better buyer–supplier relationship in the long run. 相似文献
999.
Sourav Dhar Amitava Ray Rabindranath Bera 《Peer-to-Peer Networking and Applications》2013,6(3):305-324
Always best connected (ABC) communication is an essential requirement for intelligent transportation system. In this paper, we propose a cognitive vertical handover (CVHO) engine to ensure seamless connectivity on the move. Analytic hierarchy process and artificial neural network are used for the development of the algorithm and MATLAB is used as simulation platform. The CVHO engine, which is knowledge based context aware system, takes into account multiple relevant criteria and previous experiences. This system is capable of performing both voluntary and reflex actions. A detailed literature review is presented to compare this work with the conventional methods of vertical handover. A case study, considering the network selection in a typical highway traffic scenario, which consists of both peer-to-peer (P2P) and mobile networks, is presented for the validation of the design. Three radio access technologies, WLAN (P2P), UMTS and WiMAX (mobile networks), are considered for simulation. The results show that the presented model not only realistically optimizes the best available network on the move but also avoids unnecessary handovers. This algorithm is specific to vehicular communication system and hence variation in network selection with vehicle speed is shown. 相似文献
1000.
Aditi Majumder Ezekiel S. Bhasker Ray Juang 《Journal of the Society for Information Display》2008,16(3):481-491
Abstract— Tiled displays provide high resolution and large scale simultaneously. Projectors can project on any available surface. Thus, it is possible to create a large high‐resolution display by simply tiling multiple projectors on any available regular surface. The tremendous advancement in projection technology has made projectors portable and affordable. One can envision displays made of multiple such projectors that can be packed in one's car trunk, carried from one location to another, deployed at each location easily to create a seamless high‐resolution display, and, finally, dismantled in minutes to be taken to the next location — essentially a pack‐and‐go display. Several challenges must be overcome in order to realize such pack‐and‐go displays. These include allowing for imperfect uncalibrated devices, uneven non‐diffused display surfaces, and a layman user via complete automation in deployment that requires no user invention. We described the advances we have made in addressing these challenges for the most common case of planar display surfaces. First, we present a technique to allow imperfect projectors. Next, we present a technique to allow a photometrically uncalibrated camera. Finally, we present a novel distributed architecture that renders critical display capabilities such as self‐calibration, scalability, and reconfigurability without any user intervention. These advances are important milestones towards the development of easy‐to‐use multi‐projector displays that can be deployed anywhere and by anyone. 相似文献