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201.
202.
To evade signature-based detection, metamorphic viruses transform their code before each new infection. Software similarity measures are a potentially useful means of detecting such malware. We can compare a given file to a known sample of metamorphic malware and compute their similarity—if they are sufficiently similar, we classify the file as malware of the same family. In this paper, we analyze an opcode-based software similarity measure inspired by simple substitution cipher cryptanalysis. We show that the technique provides a useful means of classifying metamorphic malware. 相似文献
203.
Richard Parkinson 《Information Systems Management》2013,30(4):69-73
Abstract Because most of the expenses in an MIS budget are not as apparent as other departmental budgets, senior managers often cut the MIS budget when they need to control financial costs – without realizing the impact on end-user departments. To avoid these arbitrary cuts, MIS managers face the difficult task of justifying their budget increases. This column describes how MIS managers can save their budgets from unnecessary cuts by promoting MIS expenses as capital investments and by planning for future costs. 相似文献
204.
Object-oriented design is an approach to systems development that proposes the use of system objects to build new systems and rebuild old ones. An important goal of object-oriented development is to change the nature of traditional software development from designing and writing models from scratch to building systems through the assembly of reusable software objects. This article discusses the productivity potential as well as the limitations of object-oriented systems development and makes recommendations for its use. 相似文献
205.
Richard J. Murray 《Information Systems Management》2013,30(3):7-15
Abstract In today's competitive world, many organizations are pursuing total quality improvement programs, and as a result of these initiatives, are seeking to define world class capabilities. The organizations with these aspirations are trying to improve product and service quality, business process quality, or delivered quality, and are becoming aware that information technology is playing a more substantial role in realizing these quality goals. 相似文献
206.
Rebecca C. Hedreen Jennifer L. Johnson Mack A. Lundy Peg Burnette Carol Perryman Guus Van Den Brekel 《国际互联网参考资料服务季刊》2013,18(2-3):167-195
ABSTRACT In April 2006, Alliance Library System and Online Programming for All Libraries partnered to start the Second Life Library 2.0 in the online world Second Life and in August 2006 purchased an island on the Teen grid of Teen Second Life. Second Life is a virtual world, a descendant of multiplayer online games. Educational institutions have recently been drawn into Second Life's robust economy and vibrant cultural life. The Second Life Library 2.0 works with librarians from around the world and with other educational partners such as TechSoup, WorldBridges, and the New Media Consortium. Second Life Library 2.0 provides “traditional” library services such as ready reference, book discussions, and search assistance, but, at heart, it explores what it means to be a virtual library in a virtual world. 相似文献
207.
208.
保证所有管道中石油从一端流向另一端不泄漏要比它的探测更加困难。比较图中的3个系统,可以看到这项技术在40多年来是如何逐步发展的。 相似文献
209.
OBJECTIVE: The present study examined Web-based information retrieval as a function of age for two information organization schemes: hierarchical organization and one organized around tags or keywords. BACKGROUND: Older adults' performance in information retrieval tasks has traditionally been lower compared with younger adults'. The current study examined the degree to which information organization moderated age-related performance differences on an information retrieval task. The theory of fluid and crystallized intelligence may provide insight into different kinds of information architectures that may reduce age-related differences in computer-based information retrieval performance. METHOD: Fifty younger (18-23 years of age) and 50 older (55-76 years of age) participants browsed a Web site for answers to specific questions. Half of the participants browsed the hierarchically organized system (taxonomy), which maintained a one-to-one relationship between menu link and page, whereas the other half browsed the tag-based interface, with a many-to-one relationship between menu and page. This difference was expected to interact with age-related differences in fluid and crystallized intelligence. RESULTS: Age-related differences in information retrieval performance persisted; however, a tag-based retrieval interface reduced age-related differences, as compared with a taxonomical interface. CONCLUSION: Cognitive aging theory can lead to interface interventions that reduce age-related differences in performance with technology. In an information retrieval paradigm, older adults may be able to leverage their increased crystallized intelligence to offset fluid intelligence declines in a computer-based information search task. APPLICATION: More research is necessary, but the results suggest that information retrieval interfaces organized around keywords may reduce age-related differences in performance. 相似文献
210.
Dowson N Bowden R 《IEEE transactions on pattern analysis and machine intelligence》2008,30(1):180-185
Mutual Information (MI) is popular for registration via function optimisation. This work proposes an inverse compositional formulation of MI for Levenberg-Marquardt optimisation. This yields a constant Hessian, which may be pre-computed. Speed improvements of 15% were obtained, with convergence accuracies similar to those of the standard formulation. 相似文献