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71.

Delay Tolerant Networks are a type of challenging, uninterrupted network in which there is not an end-to-end path between the source and the destination. These networks play a key role in managing crises in natural disasters such as earthquakes, fires, floods, and more. Due to limited resources, nodes may be reluctant to cooperate in the message relaying and may behave selfishly. Eventually, this lack of cooperation can result in performance degradation. Game theory is one of the mathematical tools to motivate the intermediate nodes to forward messages. In this paper, we use the theory of auction between relay nodes to motivate them to collaborate in forwarding messages. Based on the second-price sealed-bid auction mechanism, the node that does not cooperate in forwarding messages fails to acquire utility. In this way, if the node itself intends to send a message to another node, it will not be able to do so due to a lack of budget. Thus, the selfish behavior of the node causes it to be harmed. Our simulations using the ONE simulator shows that the performance of the proposed method in moderate traffic is improved in terms of significant criteria such as delivery ratio, average buffer usage, hop count, overhead, and so on. The results also show that under intense traffic conditions, the performance of the proposed method is far better than that of moderate traffic.

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72.
Multimedia Tools and Applications - Multiple human 3D pose estimation is a challenging task. It is mainly because of large variations in the scale and pose of humans, fast motions, multiple persons...  相似文献   
73.
The importance of using adaptive traffic signal control for figuring out the unpredictable traffic congestion in today’s metropolitan life cannot be overemphasized. The vehicular ad hoc network (VANET), as an integral component of intelligent transportation systems (ITSs), is a new potent technology that has recently gained the attention of academics to replace traditional instruments for providing information for adaptive traffic signal controlling systems (TSCSs). Meanwhile, the suggestions of VANET-based TSCS approaches have some weaknesses: (1) imperfect compatibility of signal timing algorithms with the obtained VANET-based data types, and (2) inefficient process of gathering and transmitting vehicle density information from the perspective of network quality of service (QoS). This paper proposes an approach that reduces the aforementioned problems and improves the performance of TSCS by decreasing the vehicle waiting time, and subsequently their pollutant emissions at intersections. To achieve these goals, a combination of vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communications is used. The V2V communication scheme incorporates the procedure of density calculation of vehicles in clusters, and V2I communication is employed to transfer the computed density information and prioritized movements information to the road side traffic controller. The main traffic input for applying traffic assessment in this approach is the queue length of vehicle clusters at the intersections. The proposed approach is compared with one of the popular VANET-based related approaches called MC-DRIVE in addition to the traditional simple adaptive TSCS that uses the Webster method. The evaluation results show the superiority of the proposed approach based on both traffic and network QoS criteria.  相似文献   
74.
叔丁醇脱水生产异丁烯的关键是如何及时将叔丁醇生产异丁烯过程中的副产水移去。本实验首次采用三元共沸脱水剂的新技术,及时把副产物移走,以保证异丁烯生成速率高且平稳。实际生产表明:运用该新技术生产异丁烯比目前国内其它生产技术生产异丁烯速度提高5~6倍。  相似文献   
75.
This paper proposes a genetic algorithm-based heuristic for the capacitated lotsizing problem in flow shops with sequence-dependent setups. The proposed heuristic combines genetic algorithm with rolling horizon approach. To evaluate the effectiveness of the proposed heuristic, some numerical experiments are conducted and corresponding results are compared with those of previously developed heuristics by authors. The comparative results indicate the superiority of genetic algorithm-based heuristic specially in solving the large-sized problem instances.  相似文献   
76.
This paper considers a two-stage hybrid flowshop scheduling problem in machine breakdown condition. By machine breakdown condition we mean that the machine may not always be available during the scheduling period. Machine failure may occur with a known probability after completing a job. Probability of machine failure depends on the previous processed job. The problem to be studied has one machine at the first stage and M parallel identical machines at the second stage. The objective is to find the optimal job combinations and the optimal job schedule such that the makespan is minimized. The proposed problem is compatible with a large scope of real world situations. To solve the problem, first, we introduce one optimal approach for job precedence when there is one machine in both stages and then provide a heuristic algorithm when there are M machines in stage two. To examine the performance of the heuristic, some experiments used are provided as well.  相似文献   
77.
The effects of transglutaminase treatment (0–2 units/g milk protein) on the chemical composition, textural characteristics, proteolysis and yield of reduced-fat Iranian white cheese (milk fat: 0.4–1.4% w/w) incorporated with whey proteins (0–6 g/L milk) were investigated. Enzyme-mediated inclusion of whey proteins in the reduced-fat cheese caused a noticeable increase in moisture to protein (M:P) ratio with concomitant decease in the hardness rheological parameters of fracture stress and Young’s and storage (G’) moduli. However, increase in concentrations of whey proteins or/and transglutaminase enzyme above a critical level led to formation of a cheese matrix with lower moisture content and greater values of hardness indices. Whey protein addition and transglutaminase treatment resulted in the same trends of changes in proteolysis rate and cheese yield as in cheese softness. Response surface method (RSM) suggested that the enzymatic incorporation of 4.2 g deliberately added whey proteins to 1 L of milk (1.04% w/w fat) into the cheese matrix using 0.833 unit transglutaminase per gram milk protein would provide a reduced-fat product with the softest texture and the highest yield. The scanning electron micrographs showed formation of honeycomb structures in the protein matrix of the reduced-fat sample with optimum formulation.  相似文献   
78.
Since the nature of an earthquake is the energy which is released due to tectonic events, improvements of behaviour of structures based on energy concepts have been a matter of great concern. Input energy must be dissipated by structures in order to decrease earthquake damage. For this purpose the YDBF (yielding damped braced frame) system is presented, which acts as a fuse when an earthquake occurs. Because of the high ductility of this system, damage to the main structural elements such as columns is prevented, and because of the non‐linear behaviour of such a system, which is based on the yielding of ductile steel, YDBF increases hysteretic dissipated energy. This class of dampers often yields in high or intermediate earthquake shakes and their hysteretic loops are relatively thick and stable. In this research seven YDBF system are modelled. These models are tested with various percentages of opening and the results of structural behaviour due to variation of opening percentages are compared. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
79.
80.
Telecommunication Systems - Disruption-tolerance networks (DTNs) are suitable for applications that may lack continuous network connectivity. Examples of such applications include coupon...  相似文献   
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