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1.
Comments on an article by Eidelson and Eidelson (see record 2003-03645-004) which made an important contribution, at a critical juncture, to the discussion of international conflicts by identifying core dimensions that allow for the systematic examination of the problem. Their article also posed a danger that mirrors a disturbing trend in the public discourse about conflicts and injustice. In response to the recent escalation of international violence and years of mixed results of engagement in debates centered around grievances of injustice (such as the Palestinian-Israeli conflict), many politicians, pundits, and scholars have advocated addressing conflicts by separating them from the underlying grievances and the ongoing injustice. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
This is a numerical study of a falling droplet surrounding by air under the electric field modeled with finite volume method by means of CFD. The VOF method has been employed to model the two-phase flow of the present study. Various capillary numbers are investigated to analyze the effects of electric field intensity on the falling droplet deformation. Also, the effects of electric potential on the heat transfer coefficient have been examined. The obtained results showed that by applying the electric field at a capillary number of 0.2 the droplet tends to retain its primitive shape as time goes by, with a subtle deformation to an oblate form. Intensifying the electric field to a capillary number of 0.8 droplet deformation is almost insignificant with time progressing; however, further enhancement in capillary number to 2 causes the droplet to deform as a prolate shape and higher values of this number intensify the prolate form deformation of the droplet and result in pinch-off phenomenon. Ultimately, it is showed that as the electric potential augments the heat transfer coefficient increases in which for electric potential values higher than 2400 V the heat transfer coefficient enhances significantly.  相似文献   
3.
The Journal of Supercomputing - Software evolution is a natural phenomenon due to the changing requirements. Understanding the program structure is a significant and complicated factor in...  相似文献   
4.
Cytomegalovirus (CMV) PCR from stool specimens was adopted as a diagnostic tool for patients with suspected CMV colitis. After being established, the method was evaluated in 17 AIDS patients and 19 other immunocompromised patients by comparison of PCR results with clinical, histological, and microbiological or virological data. CMV PCR was positive in 4 symptomatic patients with proven CMV colitis and negative in 15 of 16 patients without characteristic histopathology. Neither CMV immunoglobulin G seropositivity nor intestinal symptoms alone were significantly associated with positive PCR results, but severe active systemic CMV infection may lead to a positive PCR. Absence of CMV DNA in stool samples may prove useful in ruling out CMV related colitis.  相似文献   
5.
A report is presented on four HIV-positive homosexual men examined after several months of exposure during cleaning of a flat from masses of pigeon droppings heavily colonized by Cryptococcus neoformans. Only one out of the four persons, with a CD4 lymphocyte count of 50/microL, fell sick from systemic cryptococcosis, but not the others, with CD4 lymphocyte counts of 180, 250, and 630/microL, respectively; they remained clinically and mycologically inconspicuous and free from C. neoformans. Open questions in view of the epidemiology of opportunistic pathogens in AIDS are discussed with regard to the CD4 cell count as a parameter indicating a predisposition for cryptococcosis as an airborne AIDS-defining opportunistic infection. This has been confirmed by specific cultural diagnosis of the agent in both the environment and the patient. Already in 1987/88, the probable source of infection had been the subject of epidemiological studies on C. neoformans in Berlin.  相似文献   
6.
A market-based computational grid is made up of large sets of heterogeneous and geographically distributed resources that are gathered into virtual organizations for executing consumer’s applications. One of the most important challenges in market-based grid systems is the management of grid users, which is called resource providers and consumers. The existing methods provide some alternative mechanisms for this problem, but they are not fully adequate. To address this problem, we propose an enhanced approach for adjusting price of grid resource using new effective parameters of microeconomic issue and also for prioritizing current jobs in the queue. This proposed approach is integrated with a cooperative method among local schedulers to accept jobs based on auction model. The results conclude that the inclusion of new parameters in price-adjusting affects the payment budget and job submission behavior of the schedulers. The evaluations of experimental results prove a remarkable performance of the proposed approach in diverse conditions and job workloads.  相似文献   
7.
In this paper, we consider the different algorithmic and game-theoretic features of scheduling. We apply concepts of cooperative game theory to study states in which a set of brokers encounters ultra combinative costs. These states appear in a diversity of scheduling factors, such as facility location and network design. Although cooperation is improbable when costs are ultra combinative, the motivation to avoid cooperation may lead to an increase in negative externalities. We study the smallest core value of a cooperative game as a means of persuading cooperation. We prove that calculating the smallest core value of ultra combinative cost cooperative games is strongly NP-hard, and we design an approximation structure for this problem that in the margin produces a (3?+?σ)-estimation algorithm. We also apply our approximation structure to get better results for two cases of ultra combinative cost cooperative games that derive from scheduling and matroid optimization.  相似文献   
8.
Multi-walled carbon nanotubes (MWCNTs) were used in the low-viscosity, thermosetting polyester epoxy/amine resin LY-5052 with high temperature resistance to fabricate MWCNT/epoxy composites. Tensile tests of the specimens were carried out to obtain mechanical properties of MWCNT/epoxy composites for various weight-percents (wt.%) of MWCNTs. Experimental results show that the Young’s modulus and the tensile strength of the composites can be significantly improved by adding a small percentage of MWCNT. A new form of the rule of mixtures, including an exponential shape function, length efficiency parameter, orientation efficiency factor and a waviness parameter, is proposed for a more accurate prediction of the mechanical properties of MWCNT-reinforced epoxy composites, for both low and high wt.% ranges. In order to verify the suitability of the model, the ensuing predictions are compared to the available experimental data in the literature. Results demonstrate a good predictability of the modified form over a wide range of tests.  相似文献   
9.
This is a numerical study of a falling droplet surrounding by air under the electric field modeled with finite volume method by means of CFD. The VOF method has been employed to model the two-phase flow of the present study. Various capillary numbers are investigated to analyze the effects of electric field intensity on the falling droplet deformation. Also, the effects of electric potential on the heat transfer coefficient have been examined. The obtained results showed that by applying the electric field at a capillary number of 0.2 the droplet tends to retain its primitive shape as time goes by, with a subtle deformation to an oblate form. Intensifying the electric field to a capillary number of 0.8 droplet deformation is almost insignificant with time progressing; however, further enhancement in capillary number to 2 causes the droplet to deform as a prolate shape and higher values of this number intensify the prolate form deformation of the droplet and result in pinch-off phenomenon. Ultimately, it is showed that as the electric potential augments the heat transfer coefficient increases in which for electric potential values higher than 2400 V the heat transfer coefficient enhances significantly.  相似文献   
10.
Queuing networks present as beneficial models for a category of problems emerging in modern manufacturing systems. As the optimal control problem for queuing networks in familiar to be difficult, an important topic of research during the last two decades has been the growth of difficult estimations, and the use of these estimations to control optimal controls. Flexible moderations are an important class of such estimations that have received much consideration in recent years. The central objective of this paper is to determine the utilization of flexible moderations in solving a diversity of scheduling problems. In this paper, we investigate the role of flexible moderations in solving classic job shop problems. For the job shop problem with the objective of minimizing makespan, we build a schedule that is guaranteed to be within a consistent of the optimal. In other words, we examine the job shop scheduling problem with the aim of minimizing holding costs. Recent results show that for this objective, the job shop problem does not have a polynomial time estimation plan; consequently, in terms of approximability, this is a harder objective than the makespan. Our main result is an algorithm, based on regular relaxation that presents lateral optimal schedules.  相似文献   
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