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11.
High‐pressure vapour‐liquid equilibria for binary and ternary high polar and asymmetric systems are calculated using the Peng‐Robinson‐Stryjek‐Vera equation of state coupled with the Twu‐Coon (TWMR), the Orbey‐Sandler (OSMR) and the Wong‐Sandler (WSMR) mixing rules. Modified UNIFAC model is used for determining the activity coefficient and excess Gibbs free energy. The calculated results are compared with the experimental data and good agreement is observed. The average absolute deviation percents (AAD%)s indicated that the WSMR has less AAD% than other mixing rules in most of cases. 相似文献
12.
Multimedia Tools and Applications - Image retargeting is the task of making images capable of being displayed on screens with different sizes. This work should be done so that high-level visual... 相似文献
13.
Amir Khakbaz Ali S. Nookabadi S. Nader Shetab-bushehri 《Networks and Spatial Economics》2013,13(1):43-66
Traffic congestion is one of the main problems in large cities for which several approaches have been proposed. Park-and-ride is one of the best approaches that can remove traffic from the traffic network. Park-and-ride facilities are an important part of urban mass transit systems, effectively extending the service area and attracting commuters and other people who may not otherwise have used mass transit. However, its efficiency depends on its location in the urban network. In this research, we focus on travel time of shortest paths instead of the distance criterion for computing network traffic and develop a model for finding the best location(s) for siting park-and-ride systems so as to minimize the network traffic. The model is formulated based on population points, potential sites for park-and-ride establishment, and several Central Business District (CBDs). Then we present a Genetic algorithm that has been proved to be efficient in solving large size problems. Finally, the proposed model is used to locate park-and-ride facilities in the city of Isfahan, Iran. 相似文献
14.
Shahad Alyousif Mohammed Dauwed Rafal Nader Mohammed Hasan Ali Mustafa Musa Jabar Ahmed Alkhayyat 《计算机、材料和连续体(英文)》2023,75(1):531-546
The number of mobile devices accessing wireless networks is skyrocketing due to the rapid advancement of sensors and wireless communication technology. In the upcoming years, it is anticipated that mobile data traffic would rise even more. The development of a new cellular network paradigm is being driven by the Internet of Things, smart homes, and more sophisticated applications with greater data rates and latency requirements. Resources are being used up quickly due to the steady growth of smartphone devices and multimedia apps. Computation offloading to either several distant clouds or close mobile devices has consistently improved the performance of mobile devices. The computation latency can also be decreased by offloading computing duties to edge servers with a specific level of computing power. Device-to-device (D2D) collaboration can assist in processing small-scale activities that are time-sensitive in order to further reduce task delays. The task offloading performance is drastically reduced due to the variation of different performance capabilities of edge nodes. Therefore, this paper addressed this problem and proposed a new method for D2D communication. In this method, the time delay is reduced by enabling the edge nodes to exchange data samples. Simulation results show that the proposed algorithm has better performance than traditional algorithm. 相似文献
15.
While scan-based compression is widely utilized in order to alleviate the test time and data volume problems,the overall compression level is dictated not only by the chain to channel ratio but also the ratio of encodable patterns.Aggressively increasing the number of scan chains in an effort to raise the compression levels may reduce the ratio of encodable patterns,degrading the overall compression level.In this paper,we present various methods to improve the ratio of encodable patterns.These methods are b... 相似文献
16.
Hossein Tehrani Nik Nejad Nobuhiro Sugimura Koji Iwamura Yoshitaka Tanimizu 《Journal of Intelligent Manufacturing》2010,21(4):487-499
Due to rapid changes of markets and pressures of competitions, industries are adopting their production ways to support diversity
of customer’s needs and increase of new product developments. This paper deals with development of an agent-based architecture
of dynamic systems for process planning in the manufacturing systems. In consideration of alternative manufacturing processes
and machine tools, the process plans and the schedules of the manufacturing resources are generated incrementally and dynamically.
A previously proposed negotiation protocol is customized and improved to generate suitable process plans for the target products
real-timely and dynamically, based on the alternative manufacturing processes. The alternative manufacturing processes are
presented by the process plan networks and the suitable process plans are searched and generated to cope with both the dynamic
status and disturbances of the manufacturing systems. We initiatively combine the heuristic search algorithms of the process
plan networks with the negotiation protocols, in order to generate suitable process plans. 相似文献
17.
18.
Pandian Vasant Nader Barsoum 《Engineering Applications of Artificial Intelligence》2009,22(4-5):767-777
Many engineering, science, information technology and management optimization problems can be considered as non-linear programming real-world problems where all or some of the parameters and variables involved are uncertain in nature. These can only be quantified using intelligent computational techniques such as evolutionary computation and fuzzy logic. The main objective of this research paper is to solve non-linear fuzzy optimization problem where the technological coefficient in the constraints involved are fuzzy numbers, which was represented by logistic membership functions using the hybrid evolutionary optimization approach. To explore the applicability of the present study, a numerical example is considered to determine the production planning for the decision variables and profit of the company. 相似文献
19.
The assumption of proportional hazards (PH) fundamental to the Cox PH model sometimes may not hold in practice. In this paper, we propose a generalization of the Cox PH model in terms of the cumulative hazard function taking a form similar to the Cox PH model, with the extension that the baseline cumulative hazard function is raised to a power function. Our model allows for interaction between covariates and the baseline hazard and it also includes, for the two sample problem, the case of two Weibull distributions and two extreme value distributions differing in both scale and shape parameters. The partial likelihood approach can not be applied here to estimate the model parameters. We use the full likelihood approach via a cubic B-spline approximation for the baseline hazard to estimate the model parameters. A semi-automatic procedure for knot selection based on Akaike’s information criterion is developed. We illustrate the applicability of our approach using real-life data. 相似文献
20.
The contribution of this paper is three empirical evaluations of a reference model for the practice of software reuse. Our
research thesis is that software development based upon a software reuse reference model improves quality of products, productivity
of processes and product time‐to‐market for many software development enterprises. The definition and investigation of such
a model has been carried out using three steps. First, the reference model is developed based on existing software reuse concepts.
Second, this reference model is empirically evaluated using three studies: one using a survey method, one using a case studies
method, and one using a legacy studies method. Third, the impact of the reference model on software development productivity,
quality, and time‐to‐market is empirically derived.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献