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991.
Aylin Ozkan Ted Kesik Ayse Zerrin Yilmaz William O’Brien 《Building Research & Information》2019,47(5):493-517
ABSTRACTIn the face of climate change, and as building codes and standards evolve to promote increased building energy efficiency and reduced carbon footprints, it is also important to ensure that buildings, especially housing, can withstand prolonged power outages during extended periods of both extreme cold and hot weather to provide habitable shelter passively. This paper examines an approach for visualizing the impact of robust passive measures in multi-unit residential buildings by examining the ‘weakest links in the chain’ – the suites most susceptible to underperforming – in three climatic zones: Toronto and Vancouver, Canada; and Adana, Turkey. Two time-based and thermal comfort-related metrics are explored: thermal autonomy, a measure of what fraction of the time a building can deliver comfort without supplemental active systems; and passive survivability (also termed thermal resilience), a measure of the length of time a building remains habitable following the onset of a prolonged power outage during a period of extended extreme weather. A visualization of the results of parametric building energy simulations helps guide the selection of passive architectural parameters at the early stages of design to promote enhanced environmental performance and resilience. 相似文献
992.
针对目前大量信息安全设备调配保障工作仍依靠人工方式进行调配的现状,文中提出一种基于机器学习算法的信息安全设备调配保障技术。在深入研究现有信息安全设备调配保障方案的基础上,分析方案中所有影响设备调配的属性特征;根据现有信息安全设备调配保障方案与提取的属性特征构造设备调配保障样本集;使用随机森林算法对属性特征进行优化,并选取最为合理的属性特征,结合支持向量机算法构造调配保障模型。实验对比结果表明,使用随机森林算法进行特征优化后的模型测试集准确率上升约8%,模型运行时间缩短43%,在解决实际问题过程中,与原方案的调配结果误差率下降了8.69%。 相似文献
993.
为了提高箭载无线传感网络对火箭温度、冲击、热流等物理参数的处理能力,需对所采集的数据进行自适应延时分配,因此设计一种基于时隙窗口间隔均衡控制的无线传感器网络数据传输延时分配算法。构建火箭温度、振动、冲击等参数的数据采集模型,采用分布式网格均衡配置方法对无线传感器网络中的节点进行均衡部署;结合最短路径寻优方法使数据采集过程中的信道分配达到均衡,构建数据采集最短路径寻优控制模型,采用输出比特序列重组方法进行数据采集过程中的传输延迟配置;结合码元调节技术对数据传输进行自适应扩频调节,利用时隙窗口间隔均衡控制方法实现无线传感器网络数据传输延时分配。实验结果表明,采用该方法进行无线传感器网络数据传输延时分配的自适应性较好,输出稳定性较强、分配输出错误率低,有效性更强。 相似文献
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Coverage is an important issue for resources rational allocation, cognitive tasks completion in sensor networks. The mobility, communicability and learning ability of smart sensors have received much attention in the past decade. Based on the deep study of game theory, a mobile sensor non-cooperative game model is established for the sensor network deployment and a local information-based topology control (LITC) algorithm for coverage enhancement is proposed. We both consider revenue of the monitoring events and neighboring sensors to avoid nodes aggregation when formulating the utility function. We then prove that the non-cooperative game is an exact potential game in which Nash Equilibrium exists. The proposed algorithm focuses on the local information of the neighboring sensors and decides sensors’ next action based on the actions of the other sensors, which maximizes its own utility function. We finally evaluate the performance of the proposed method through simulations. Simulation results demonstrate that the proposed algorithm can enlarge the coverage of the entire monitoring area while achieving effective coverage of the events. 相似文献
996.
开展水量水质双控约束下水资源优化配置研究是落实新时期"节水优先"方针、保障区域水安全和促进水资源可持续利用的基础支撑。针对我国北方地区资源型缺水、工程型缺水并存的问题,以山东省昌乐县为例,结合WEAP模型与传统水资源配置理论方法,根据区域用水需求与总量控制及水功能区限制纳污管控要求,统筹协调生活、生产、生态用水,建立基于水量水质双控的区域水资源优化配置模型,采用AHP法、熵权法、AHP-熵权耦合法计算不同情景方案的配置效益并优选配置方案。结果表明:规划水平年农业、城市供水保证率分别为50%、95%时,基于用水总量控制的跨流域调水、强化行业节水和水污染治理以及加大再生水回用相结合的配置方案(B4方案)综合效益最大,各行业用水需求均能得到满足,GDP较现状水平年增加709.01亿元,再生水利用率提高至25%。 相似文献
997.
Michael Chien‐Chun Hung Kate Ching‐Ju Lin 《Wireless Communications and Mobile Computing》2016,16(2):209-222
In this paper, we investigate the problem of joint sink deployment and association (JSDA) in multi‐sink wireless camera networks (WCNs). Each camera in a WCN requires a different streaming rate of delivering its stream back to an access point (sink) because of various surveillance requirements, for example, event detection or target tracking. In a WCN where multiple channels are supported, the sinks must be placed in suitable locations (sink deployment) to collect streams from cameras over nonoverlapping channels, and in addition, each camera must associate with the appropriate sink (sink association) so that its demand rate can be optimally satisfied. To achieve this goal, we first formulate the JSDA problem as an optimization model using mixed‐integer linear programming and prove its NP‐completeness. Two approaches, branch‐and‐bound and our heuristics, iterative sink deployment and association (ISDA), are then developed to solve JSDA. We evaluate the performance via simulations with the traces collected by real measurements and show that ISDA can effectively satisfy cameras' demands with a reasonable computational cost. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
998.
Optimizing content routers deployment in large‐scale information centric core‐edge separation Internet 下载免费PDF全文
Jia Chen Hongke Zhang Huachun Zhou Hongbin Luo 《International Journal of Communication Systems》2014,27(5):794-810
In this paper, we investigate the optimization of content router deployment in large‐scale information centric core‐edge separation Internet. We formulate the target cost function, which captures the trade‐off between the cost for traffic transmission and cost due to additional deployment of content routers. To solve the problem, we first derive the analytical results of traffic ratio and its closed‐form approximation. We then construct a convex optimization problem, from which the optimal deployment probability can be solved. By extensive numerical results, the accuracy of the closed‐form approximation of traffic ratio is demonstrated. And, it is found that the optimal deployment probability is decided by the average number of hops for obtaining the content, the cost for traffic transmission, and the cost of extending router to content router. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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