Institution
Concordia University
Education•Montreal, Quebec, Canada•
About: Concordia University is a education organization based out in Montreal, Quebec, Canada. It is known for research contribution in the topics: Control theory & Population. The organization has 13565 authors who have published 31084 publications receiving 783525 citations. The organization is also known as: Sir George Williams University & Loyola College, Montreal.
Papers published on a yearly basis
Papers
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01 Oct 1986TL;DR: In this paper, the authors identify a set of variables associated with successful small businesses and conduct a pilot study which endeavours to identify the variables that are associated with success in small businesses.
Abstract: This empirical research is a pilot study which endeavours to identify a set of variables associated with successful small businesses. Seventy-four (74) small firms operating in Montreal responded t...
264 citations
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TL;DR: The effective dose of DAMGO--both for establishing and for maintaining the lever-press habit--was 100 times lower than the effective doses for DPDPE and morphine, suggesting that the major contribution of VTA mechanisms to intravenous heroin self- administration involves an action on mu-opioid receptors.
Abstract: Intracranial self-administration of mu- and delta-opioid agonists was demonstrated in male Long-Evans rats. Independent groups were allowed to lever-press for ventral tegmental area (VTA) microinfusions of morphine, the selective mu agonist [D-Ala2,N-Me-Phe4-Gly5-ol]- enkephalin (DAMGO), the selective delta-agonist [D-Pen2,D-Pen5]- enkephalin (DPDPE), or ineffective drug vehicle. Morphine, DAMGO, and DPDPE were each effective in establishing and maintaining lever- pressing habits. Lever-pressing responses were extinguished during a session when vehicle was substituted for drug, and reinstated when drug reinforcement was reestablished. Thus, it appears that VTA mu- and delta-opioid receptors are each involved in reinforcement of opiate self-administration. The effective dose of DAMGO--both for establishing and for maintaining the lever-press habit--was 100 times lower than the effective doses for DPDPE and morphine, suggesting that the major contribution of VTA mechanisms to intravenous heroin self- administration involves an action on mu-opioid receptors.
264 citations
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TL;DR: An efficient neural network shortest path algorithm that is an improved version of previously suggested Hopfield models is proposed that will enable the routing algorithm to be implemented in real time and also to be adaptive to changes in link costs and network topology.
Abstract: The application of neural networks to the optimum routing problem in packet-switched computer networks, where the goal is to minimize the network-wide average time delay, is addressed. Under appropriate assumptions, the optimum routing algorithm relies heavily on shortest path computations that have to be carried out in real time. For this purpose an efficient neural network shortest path algorithm that is an improved version of previously suggested Hopfield models is proposed. The general principles involved in the design of the proposed neural network are discussed in detail. Its computational power is demonstrated through computer simulations. One of the main features of the proposed model is that it will enable the routing algorithm to be implemented in real time and also to be adaptive to changes in link costs and network topology. >
264 citations
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TL;DR: It is shown that as the intercept probability requirement is relaxed, the outage performance of the direct transmission, the artificial noise based and the relay selection schemes improves, and vice versa, and the SRTs of the single-relay and multi-relays selection approaches significantly improve.
Abstract: We consider a cognitive radio (CR) network consisting of a secondary transmitter (ST), a secondary destination (SD) and multiple secondary relays (SRs) in the presence of an eavesdropper, where the ST transmits to the SD with the assistance of SRs, while the eavesdropper attempts to intercept the secondary transmission. We rely on careful relay selection for protecting the ST-SD transmission against the eavesdropper with the aid of both single-relay and multi-relay selection. To be specific, only the “best” SR is chosen in the single-relay selection for assisting the secondary transmission, whereas the multi-relay selection invokes multiple SRs for simultaneously forwarding the ST's transmission to the SD. We analyze both the intercept probability and outage probability of the proposed single-relay and multi-relay selection schemes for the secondary transmission relying on realistic spectrum sensing. We also evaluate the performance of classic direct transmission and artificial noise based methods for the purpose of comparison with the proposed relay selection schemes. It is shown that as the intercept probability requirement is relaxed, the outage performance of the direct transmission, the artificial noise based and the relay selection schemes improves, and vice versa. This implies a trade-off between the security and reliability of the secondary transmission in the presence of eavesdropping attacks, which is referred to as the security-reliability trade-off (SRT). Furthermore, we demonstrate that the SRTs of the single-relay and multi-relay selection schemes are generally better than that of classic direct transmission, explicitly demonstrating the advantage of the proposed relay selection in terms of protecting the secondary transmissions against eavesdropping attacks. Moreover, as the number of SRs increases, the SRTs of the proposed single-relay and multi-relay selection approaches significantly improve. Finally, our numerical results show that as expected, the multi-relay selection scheme achieves a better SRT performance than the single-relay selection.
263 citations
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27 Oct 2008TL;DR: A Dynamic Bayesian Networks-based model is proposed to incorporate temporal factors, such as the availability of exploit codes or patches, for continuously measuring network security in a dynamic environment.
Abstract: Given the increasing dependence of our societies on networked information systems, the overall security of these systems should be measured and improved. Existing security metrics have generally focused on measuring individual vulnerabilities without considering their combined effects. Our previous work tackle this issue by exploring the causal relationships between vulnerabilities encoded in an attack graph. However, the evolving nature of vulnerabilities and networks has largely been ignored. In this paper, we propose a Dynamic Bayesian Networks (DBNs)-based model to incorporate temporal factors, such as the availability of exploit codes or patches. Starting from the model, we study two concrete cases to demonstrate the potential applications. This novel model provides a theoretical foundation and a practical framework for continuously measuring network security in a dynamic environment.
262 citations
Authors
Showing all 13754 results
Name | H-index | Papers | Citations |
---|---|---|---|
Alan C. Evans | 183 | 866 | 134642 |
Michael J. Meaney | 136 | 604 | 81128 |
Chao Zhang | 127 | 3119 | 84711 |
Charles Spence | 111 | 949 | 51159 |
Angappa Gunasekaran | 101 | 586 | 40633 |
Kaushik Roy | 97 | 1402 | 42661 |
Muthiah Manoharan | 96 | 497 | 44464 |
Stephen J. Simpson | 95 | 490 | 30226 |
Roy A. Wise | 95 | 252 | 39509 |
Dario Farina | 94 | 832 | 32786 |
Yavin Shaham | 94 | 239 | 29596 |
Elazer R. Edelman | 89 | 593 | 29980 |
Fikret Berkes | 88 | 271 | 49585 |
Ke Wu | 87 | 1242 | 33226 |
Nick Serpone | 85 | 474 | 30532 |