Power allocation,relay selection and energy cooperation strategies in energy harvesting cooperative wireless networks

In this paper, optimal power allocation and relay selection strategies in energy harvesting cooperative wireless networks are studied. In particular, signal‐to‐noise ratio (SNR)‐maximizing based power allocation and relay selection without and with energy cooperation—via wireless energy transfer—are considered. Moreover, total relay power minimization subject to target end‐to‐end SNR is investigated. The different optimal strategies are formulated as optimization problems, which are non‐convex. Thus, intelligent transformations are applied to transform non‐convex problems into convex ones, and polynomial‐time solution procedures are proposed. Simulation results illustrate that power allocation strategies achieve higher end‐to‐end SNR than relay selection ones. Finally, energy cooperation is shown to be effective in improving end‐to‐end SNR, while total relay power minimization balances end‐to‐end SNR, transmit power consumption, and harvested energy. Copyright © 2016 John Wiley & Sons, Ltd.     

Coalitional game‐based behavior analysis for spectrum access in cognitive radios

The core of cognitive radio paradigm is to introduce cognitive devices able to opportunistically access the licensed radio bands. The coexistence of licensed and unlicensed users prescribes an effective spectrum hole‐detection and a non‐interfering sharing of those frequencies. Collaborative resource allocation and spectrum information exchange are required but often costly in terms of energy and delay. In this paper, each secondary user (SU) can achieve spectrum sensing and data transmission through a coalitional game‐based mechanism. SUs are called upon to report their sensing results to the elected coalition head, which properly decides on the channel state and the transmitter in each time slot according to a proposed algorithm. The goal of this paper is to provide a more holistic view on the spectrum and enhance the cognitive system performance through SUs behavior analysis. We formulate the problem as a coalitional game in partition form with non‐transferable utility, and we investigate on the impact of both coalition formation and the combining reports costs. We discuss the Nash Equilibrium solution for our coalitional game and propose a distributed strategic learning algorithm to illustrate a concrete case of coalition formation and the SUs competitive and cooperative behaviors inter‐coalitions and intra‐coalitions. We show through simulations that cognitive network performances, the energy consumption and transmission delay, improve evidently with the proposed scheme. Copyright © 2016 John Wiley & Sons, Ltd.     

SmartRoads: tracing the limits of managing road space at the metropolitan road network scale

The task of (re)allocating existing road space has been pushed to the fore in traffic management. In Melbourne, Australia, the rise of “network operating planning” indicates renewed vigour for planners to wrestle with the challenge of managing road space at the network level—highlighted by the creation of SmartRoads. Tracing this and prior frameworks in Melbourne’s history reveals recurrent issues related to governance, cyclical debates, poor continuity and competing priorities. The issues collectively speak to a tension common in the road space allocation task: accounting for finer-grained road space use details and acknowledging small changes have network level implications. Although playing out differently depending on city, engaging the tension is central to making better informed road space allocation decisions.     

Redline Dystopias: A Dialogue With a Farmer in Qicha

For the field of national territorial planning, to identify and delimit redlines is the primary step to preserve valuable natural and cultural assets from human interventions, harmonizing human-nature and urbanrural relationships. In the reality, however, the dogmatic planning and design concepts, irrational construction standards, and unscientific and rigid management requirements that ignore the diverse localities, market rules, and stakeholders’ needs usually make the implementation outcome runs the opposite to what was wished, leading to “redline dystopias” called by the author that are damaging our homelands. This article presents a dialogue between the author and a farmer in Qicha, Hainan, to reveal how a “capital farmland dystopia,” one of the redline dystopias, comes into being, appealing for a profound re-examination and reflection in the planning and design professions.     

我国无居民海岛 PPP 项目风险分担的博弈模型

对无居民海岛进行科学合理的开发和利用是我国建设海洋强国的重要环节,为了保证我国无居民海岛 PPP 项目开发的顺利进行,公平合理的风险分担机制是至关重要的。基于地位非对称不完全信息条件下的讨价还价博弈模型,提出了我国无居民海岛 PPP 项目开发过程中政府部门和私营部门风险分担比例的确定方法,并用实例对模型进行了验证。通过对模型的分析发现,政府部门和私营部门的风险分担比例与双方地位的非对称性以及谈判损耗系数有关,谈判过程中需要引起双方的重视。研究成果为公平合理地进行风险分担提供了一定的理论依据,同时对推进我国无居民海岛 PPP 项目的开发具有一定的指导意义     

随机共因失效条件下战时合成部队携行备件配置优化研究

装备群在执行作战任务过程中通常会发生共因失效事件,分析共因失效故障对实现装备群的精确化保障具有现实意义。针对战时合成部队装备群遂行任务时,装备携行备件配置优化模型中没有考虑装备受击故障这一类随机共因失效的问题,提出了随机共因失效条件下的备件配置优化方法。建立了装备故障相关条件下的备件需求模型和多约束条件下的携行备件配置优化模型,引入拉格朗日乘子,利用边际效应法求出最优配置方案通过实例对该方法的可行性进行验证。研究结果表明,在装备随机共因失效条件下,所建立的模型可以为多约束携行备件配置优化提供模型参考。     

城市地下综合管廊定价模型及实证研究

在分析我国已建成的部分城市地下综合管廊没有充分发挥预期效果的原因的基础上,为了吸引投资和促进综合管廊的发展,笔者首先针对已有定价模型的不足,根据“谁受益,谁付费”的原则,通过专家调查和文献分析,确定了管线横截面积、管线年度经营收益、节约的管线建设成本、节约的管线维护成本和管理难度5个分摊因素。进而根据入廊费和年运营维护费确定各因素的重要程度,区分入廊费用分摊因子和年运营维护费用分摊因子,构建了一个更公平合理的定价模型。最后通过实证分析,得出各入廊管线单位负担费用均低于传统直埋方式产生费用的结论,且费用分摊更为合理,说明模型的实用性较强,对我国城市地下综合管廊的建设和发展有一定的参考价值。     

基于 IFAHP 燃油供给系统可靠性分配

为了更有效地分配燃油供给系统的可靠性指标,首先采用改进模糊层次分析法,根据模糊三标度的优先关系构建了影响燃油供给系统可靠性分配的5个因素的判断矩阵,确定了燃油供给系统故障易发的5个子系统对目标层的相对权重。然后根据综合权重对系统故障率进行分配,并由可靠度公式计算出各子系统应该分配的可靠度,计算所得结果与厂家实际统计结果相吻合,表明该方法是切实可行的,可应用于燃油供给系统的可靠性分配。     

博弈模型下云资源分配纳什均衡算法

为解决云资源分配中用户的异构性需求问题,以经济模型为基础,运用非合作博弈论研究了具有完全理性的云资源分配问题,提出基于非合作博弈的资源分配纳什均衡算法,该算法以博弈效用最优化为目标,利用正比例共享机制按用户出价分配云资源。求解了用户的出价函数,重点证明了出价函数的凹性以及多用户间的最优出价组合的纳什均衡存在性与唯一性,并提出了资源分配纳什均衡算法。实验结果表明:非合作博弈云资源分配算法不仅能够按市场变化反映资源价格与用户需求之间的浮动关系,从而规范用户间的资源公平竞争关系,而且可以使资源分配更加合理和均衡。     

空间资源配置视角下城市规划的转型策略研究——基于我国市场经济实践的思考

回顾了计划经济、市场经济以及经济体制转型中的资源配置特征,将资源配置过程分解为“设计配置方案”和“实施配置方案”两个阶段,将实施空间配置方案的过程分解为两次转化(土地要素化、土地要素空间化)、两步配置(土地要素配置、空间要素配置)和两种循环(土地要素循环、空间要素循环).基于此,分析了城市规划被动和滞后的原因,提出基于空间资源配置改进城市规划的方法论:实现空间资源配置主体、深度、模式、对象的转向,构建空间资源配置的全流程管控体系.