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1.
《Physics letters. A》2020,384(35):126904
Exploring the evolution of cooperation has been one of the most challenging topics and attracted increasing attention in various realms. Hereby, we institute an analytic model where the relationship between the common benefits and contributions is the typical saturation nonlinearity. We investigate the evolutionary dynamics of cooperation with and without consensual incentives respectively. The population always evolves to full defection when the incentives are absent. Cooperation, however, can be promoted by consensual incentives when the degree of cooperators' preferences for incentives is great. There exists an intermediate amount of resources at which the positive effect of consensual incentives on cooperation is minimized. Furthermore, there is a U-shape relationship between the degree of cooperators' preference for an incentive and the evolution of cooperation. A greater basin of full cooperation can be induced when the cooperators' preference for reward is more pronounced than that for punishment. 相似文献
2.
Vivek F. Farias 《Operations Research Letters》2006,34(2):180-190
We consider a problem of allocating limited quantities of M types of resources among N independent activities that evolve over T epochs. In each epoch, we assign to each activity a task which consumes resources, generates utility, and determines the subsequent state of the activity. We study the complexity of, and approximation algorithms for, maximizing average utility. 相似文献
3.
一种新的WDM光网中的共享链路保护策略 总被引:2,自引:2,他引:0
研究了WDM光网中的链路保护问题.提出了一种新的共享链路保护策略--基于SRLG的共享链路保护策略(SRLG-SLP).SRLG(共享风险链路组)定义了对一条工作光通道分配保护资源时的资源可用性的约束.它规定任意两条有着同样故障风险或者说处于同一个SRLG的工作光通道不能利用同样的保护资源.另外,还提出了一种更加符合实际的单链路故障模型,其中链路故障间隔时间和链路故障保持时间被考虑作为两个独立的变量.基于该链路故障模型,通过大量的仿真试验,比较了专用链路保护(DLP)、共享链路保护(SLP)和提出的SRLG-SLP保护策略的资源利用率、保护效率以及业务中断率.结果显示,我们提出的SRLG-SLP在保护效率和业务中断率方面的保护性能远好于DLP和SLP,但会牺牲一些资源利用率. 相似文献
4.
JIANG Hua ZHANG Quanxing CHEN Jinlong Nanjing Electric Power Automation Equipment General Factory The State Power Cooperation of China Nanjing China The State Key Laboratory of Pollution Control & Resources Reuse Dept. of Environme 《Chinese Journal of Reactive Polymers》2002,(1)
1. INTRODUCTION 1,2,4-acid (1-Amino-2-naphthol-4-sulfonic acid) is among the most important naphthalene derivatives which are widely used as the intermediates of dyestuffs. In its production process, however, high strength wastewater streams are gene… 相似文献
5.
Convergence speed and diversity of nondominated solutions are two important performance indicators for Multi-Objective Evolutionary Algorithms (MOEAs). In this paper, we propose a Resource Allocation (RA) model based on Game Theory to accelerate the convergence speed of MOEAs, and a novel Double-Sphere Crowding Distance (DSCD) measure to improve the diversity of nondominated solutions. The mechanism of RA model is that the individuals in each group cooperate with each other to get maximum benefits for their group, and then individuals in the same group compete for private interests. The DSCD measure uses hyper-spheres consisting of nearest neighbors to estimate the crowding degree. Experimental results on convergence speed and diversity of nondominated solutions for benchmark problems and a real-world problem show the efficiency of these two proposed techniques. 相似文献
6.
《Physics letters. A》2014,378(5-6):488-493
It is well-known that the principle of increasing entropy holds for isolated natural systems that contain non-adaptive molecules. Here we present, for the first time, an experimental evidence for a possible human counterpart of the principle in an isolated social system that involves adaptive humans. Our work shows that the human counterpart is valid even though interactions among humans in social systems are distinctly different from those among molecules in natural systems. Thus, it becomes possible to understand social systems from this natural principle, at least to some extent. 相似文献
7.
With the introduction of wireless modems and smart phones, the passenger transport industry is witnessing a high demand to ensure not only the safety of the trains, but also to provide users with Internet access all the time inside the train. When the Mobile Terminal (MT) communicates directly with the Base Station (BS), it will experience a severe degradation in the Quality of Service due to the path loss and shadowing effects as the wireless signal is traveling through the train. In this paper, we study the performance in the case of relays placed on top of each train car. In the proposed approach, these relays communicate with the cellular BS on one hand, and with the MTs inside the train cars on the other hand, using the Long Term Evolution (LTE) cellular technology. A low complexity heuristic LTE radio resource management approach is proposed and compared to the Hungarian algorithm, both in the presence and absence of the relays. The presence of the relays is shown to lead to significant enhancements in the effective data rates of the MTs. In addition, the proposed resource management approach is shown to reach a performance close to the optimal Hungarian algorithm. 相似文献
8.
Jnos Csirik Gerhard
J. Woeginger 《Journal of Algorithms in Cognition, Informatics and Logic》2002,44(2):1016
We study online bounded space bin packing in the resource augmentation model of competitive analysis. In this model, the online bounded space packing algorithm has to pack a list L of items in (0,1] into a small number of bins of size b1. Its performance is measured by comparing the produced packing against the optimal offline packing of the list L into bins of size 1.We present a complete solution to this problem: For every bin size b1, we design online bounded space bin packing algorithms whose worst case ratio in this model comes arbitrarily close to a certain bound ρ(b). Moreover, we prove that no online bounded space algorithm can perform better than ρ(b) in the worst case. 相似文献
9.
G. Malescio 《Physica A》2007,383(2):643-650
We present a model describing a generic process in which a finite resource is partitioned and distributed among agents. Through numerical simulation we show that the model considered is able to originate, within a unifying approach, a variety of broad distributions and provides an interpretation of empirical properties of distributions observed in the real world. In particular it allows to relate the exponent of the power-law part of the distributions to resource abundance and accessibility, while the left-end exponential behavior, observed in many distributions, is related to the presence of dissipative effects. 相似文献
10.
Francisco Ballestín Vicente Valls Sacramento Quintanilla 《European Journal of Operational Research》2008
The Resource-Constrained Project Scheduling Project (RCPSP), together with some of its extensions, has been widely studied. A fundamental assumption in this basic problem is that activities in progress are non-preemptable. Very little effort has been made to uncover the potential benefits of discrete activity pre-emption, and the papers dealing with this issue have reached the conclusion that it has little effect on project length when constant resource availability levels are defined. In this paper we show how three basic elements of many heuristics for the RCPSP – codification, serial SGS and double justification – can be adapted to deal with interruption. The paper is mainly focussed on problem 1_PRCPSP, a generalization of the RCPSP where a maximum of one interruption per activity is allowed. However, it is also shown how these three elements can be further adapted to deal with more general pre-emptive problems. Computational experiments on the standard j30 and j120 sets support the conclusion that pre-emption does help to decrease project length when compared to the no-interruption case. They also prove the usefulness of the justification in the presence of pre-emption. The justification is a RCPS technique that can be easily incorporated into a wide range of algorithms for the RCPSP, increasing their solution quality – maintaining the number of schedules calculated. 相似文献