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81.
Game strategies in network security 总被引:3,自引:0,他引:3
This paper presents a game-theoretic method for analyzing the security of computer networks. We view the interactions between an attacker and the administrator as a two-player stochastic game and construct a model for the game. Using a nonlinear program, we compute Nash equilibria or best-response strategies for the players (attacker and administrator). We then explain why the strategies are realistic and how administrators can use these results to enhance the security of their network. 相似文献
82.
Wing Lam 《欧洲信息系统杂志》2005,14(2):175-187
This paper investigates Critical Success Factors (CSFs) in Enterprise Application Integration (EAI). An initial set of CSFs for EAI projects was created based on a review and synthesis of the literature in the general area of integration, including Enterprise Resource Planning (ERP) projects. A case analysis, involving a large financial services provider integrating its consumer banking systems, was used to validate the CSFs. The findings resulted in a more structured and holistic CSF model which identifies three broad groups of CSFs, namely (1) top management support, (2) overall integration strategy, and (3) EAI project planning and execution. Although EAI projects share many of the same CSFs as ERP projects and other information systems projects, issues related to the selection of the right EAI tool and emphasis on technology planning and enterprise architecture are distinguishing features of EAI projects. Some of practical implications of the research are that EAI projects require personnel with specific skills and expertise, business integration should precede technology integration, that availability of adapters is an important criteria in EAI tool selection and that some custom adapter development may be unavoidable if custom applications need to be integrated. 相似文献
83.
Phil Surman Ian Sexton Richard Bates Kam Chaun Yow Wing Kai Lee 《Journal of the Society for Information Display》2005,13(4):329-334
Abstract— The De Montfort University (DMU) autostereoscopic 3‐D display, intended for television applications, is described. It provides freedom of viewer movement over a typical “living room” sized area, with no restrictions on viewer's head positions. The display is capable of supplying 3‐D images to multiple viewers who do not need to wear special glasses. It operates by producing regions (exit pupils) in the viewing field where either a left or a right image is perceived. The positions of the exit pupils are steered to the viewers' eyes by the use of head tracking. Design issues that became apparent during the construction of a first prototype, and the findings from tests on it, are described. In addition, the current status of a more advanced prototype is reported. 相似文献
84.
Lixin Wang Hamdi M. Manivasakan R. Tsang D.H.K. 《Communications, IEEE Transactions on》2006,54(3):518-531
The design of the medium-access control (MAC) protocol is the most crucial aspect for high-speed and high-performance local and metropolitan area networks, since the decisions made at this level determine the major functional characteristics of these networks. Most of the MAC protocols proposed in the literature are not suitable for multimedia applications, since they have been designed with one generic traffic type in mind. As a result, they perform quite well for the traffic types they have been designed for, but poorly for other traffic streams with different characteristics. In this paper, we propose an integrated MAC protocol called the Multimedia-MAC (M-MAC), which integrates different MAC protocols into a hybrid protocol in a shared-medium network to efficiently accommodate various types of multimedia traffic streams with different characteristics and quality-of-service demands, namely, a constant-bit-rate traffic, bursty traffic (say, variable-bit-rate traffic), and emergency messages (say, control messages). We have developed a mathematical framework for the analysis and performance evaluation of our M-MAC protocol, which involves a queueing system with vacation. We have applied our M-MAC design approach to a wavelength-division multiplexing network, and evaluated its performance under various traffic conditions. 相似文献
85.
In this paper, we analyze several metamorphic virus generators. We define a similarity index and use it to precisely quantify the degree of metamorphism that each generator produces. Then we present a detector based on hidden Markov models and we consider a simpler detection method based on our similarity index. Both of these techniques detect all of the metamorphic viruses in our test set with extremely high accuracy. In addition, we show that popular commercial virus scanners do not detect the highly metamorphic virus variants in our test set.A talk based on the results in this paper was presented by the authors at Defcon 14, August 5, 2006, Las Vegas, Nevada. 相似文献
86.
87.
A 54 year-old man had symptoms of acute right hemispheric cerebral ischemia. He was initially considered for participation in a trial of early thrombolysis in stroke, but an innominate artery embolus was found with no apparent arterial source. The embolus was removed by means of a combined brachial and carotid bifurcation approach to protect the cerebral vasculature from embolic fragmentation during extraction. Further investigation revealed deep venous thrombosis, evidence of pulmonary emboli, and a patent foramen ovale, supporting a diagnosis of paradoxic embolus. Additional treatment included anticoagulation and placement of an inferior vena caval filter. The unusual condition of paradoxic embolus is reviewed, and the management of this patient is discussed. 相似文献
88.
89.
In this paper, we describe a new buffer architecture called the Compositing Buffer. Although it is based on the A-buffer architecture described by Carpenter1, the new architecture introduces two important ideas which make image generation more flexible. The first idea is the storing of bitmask index instead of the bitmask. This allows accurate images to be generated while at the same time, minimising memory usage. The second idea is the introduction of the concept of dynamic object. This allows images to be edited interactively. Applications of the two ideas will also be discussed in the paper. 相似文献
90.
We studied 13 consecutive infants admitted to our Neonatal Intensive Care Unit over 37 months from 1 June 1994 to 30 June 1997, who were diagnosed with severe persistent pulmonary hypertension (PPHN) meeting extracorporeal membrane oxygenation (ECMO) criteria as defined by Bartlett and/or Short. They were managed with conservative ventilation strategy, with emphasis on the use of moderate ventilatory pressures whilst avoiding paralysis. Peak inspiratory pressure (PIP) on intermittent mandatory ventilation was adjusted according to adequate chest excursion. High PIP was avoided. Two main ventilatory techniques were used: 1) low ventilatory rate < or = 40/min, PIP 20 to 30 cmH2O, inspiratory time (IT) 0.5 seconds, positive end-expiratory pressure (PEEP) 5 cmH2O, and 2) high ventilatory rate 100/min, PEEP 0 cmH2O, IT 0.3 seconds. The aim was to keep preductal PaO2 > or = 50 mmHg. We did not sought to achieve alkalotic pH or low PaCO2. When PIP requirements exceeded 30 to 35 cmH2O, the use of an alternative rescue therapy such as pulmonary vasodilator, high frequency ventilation and/or surfactant were considered. Only 1 infant died of PPHN. Low mortality due to PPHN can be achieved using this strategy. There is a need for a randomised controlled trial to compare this strategy with other alternative treatment strategies. 相似文献