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1.
Energy Conservation &Environmental Protection of Waste Rubber Compr ehensive Utilization Re-upgraded
"Even though the realized profit of 38 key member enterprises increased by 14.96% in the first 7 months of this year, we shall be acutely aware of the big gap from the resource-saving and eco-friendly enterprises as the economic benefit of the industry is increasing. In particular, the environmental protection situation is severe in the current industry, so environmental protection becomes a historical mission in waste rubber comprehensive utilization industry." 相似文献
2.
Luca Bedogni Marco Di Felice Luciano Bononi 《Wireless Communications and Mobile Computing》2016,16(16):2523-2541
In this paper, we study the problem of how to detect the current transportation mode of the user from the smartphone sensors data, because this issue is considered crucial for the deployment of a multitude of mobility‐aware systems, ranging from trace collectors to health monitoring and urban sensing systems. Although some feasibility studies have been performed in the literature, most of the proposed systems rely on the utilization of the GPS and on computational expensive algorithms that do not take into account the limited resources of mobile phones. On the opposite, this paper focuses on the design and implementation of a feasible and efficient detection system that takes into account both the issues of accuracy of classification and of energy consumption. To this purpose, we propose the utilization of embedded sensor data (accelerometer/gyroscope) with a novel meta‐classifier based on a cascading technique, and we show that our combined approach can provide similar performance than a GPS‐based classifier, but introducing also the possibility to control the computational load based on requested confidence. We describe the implementation of the proposed system into an Android framework that can be leveraged by third‐part mobile applications to access context‐aware information in a transparent way. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
3.
Yong Niu Yong Li Depeng Jin Li Su Dapeng Wu 《Wireless Communications and Mobile Computing》2016,16(3):313-329
Millimeter wave (mmWave) communications in 60 GHz band have become a hot topic in wireless communications. New medium access control (MAC) protocols are needed because of the fundamental differences between mmWave communications and existing other communication systems. In mmWave wireless personal area networks, the channel transmission rates of links vary significantly because of the difference in the distance between nodes, the accuracy of beamforming, and the existence of obstructions. Owning to the directivity of mmWave links, spatial reuse should be exploited to improve network capacity. In this paper, we develop a channel transmission rate aware directional MAC protocol, termed RDMAC, in which both the multirate capability of links and spatial reuse are exploited to improve network performance. RDMAC has two stages. The first stage measures the channel transmission rates of links, and a heuristic algorithm is proposed to compute near‐optimal measurement schedules with respect to the total number of measurements. The second stage accommodates the traffic demand of links, and a heuristic transmission scheduling algorithm is proposed to compute near‐optimal transmission schedules with respect to the total transmission time. Simulations under various traffic modes show that compared with existing protocols, RDMAC has lower network latency, higher network throughput, and also a good fairness performance. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
4.
针对现有的网络编码路由技术中存在的组合优化性能较差,如计算开销较大、数据交互复杂以及路由构建周期较长等问题,以遗传算法为理论基础,提出了一种改进的网络编码感知路由算法.该算法利用遗传算法的高效组合优化功能,重新构造了其网络编码感知路由的染色体表达、适应度函数以及遗传操作等,并添加了一种修复模块.实验结果表明,该算法与同类型的网络编码路由算法相比,其平均路由构造时间较短、网络吞吐量大,展现出较强的组合优化性能,并具有强优化的寻址能力. 相似文献
5.
针对无线传感器网络(WSN)中多径路由的可靠性和能量效率问题,提出了一种基于代理和位置感知的多径路由发现方案(LABMR).事件节点根据位置信息,动态寻找其到Sink节点之间的特殊中间节点,来构建多径路由.利用移动代理来收集多径路由的局部拓扑结构信息,Sink节点根据代理收集的路由参数来计算路径权值,以此选择最优不相交路径.同时,对于信息的重要性差异,Sink节点选择单条或多条路径来传输数据,在保证传输可靠性的同时减少能耗.与现有的基于代理的多径路由(ABMR)方法相比,LABMP在数据包投递率、能量消耗、额外开销和延迟方面具有更好的性能. 相似文献
6.
针对基于内容的可变长度的分块CDC算法中数字签名计算需要耗费大量CPU开销的问题,提出了一种基于位串内容感知的数据块分块算法。算法利用每一次失败匹配尝试所带来的位特征信息,最大限度地排除不能匹配的位置,从而获得最大的跳跃长度,减少中间计算和比较的开销。实验结果表明,本算法减小了数据分块过程中数字签名计算的开销,降低了确定块边界时的CPU资源消耗,从而优化了数据分块的时间性能。 相似文献
7.
How to reduce power consumption of data centers has received worldwide attention. By combining the energy-aware data placement policy and locality-aware multi-job scheduling scheme, we propose a new multi-objective bi-level programming model based on MapReduce to improve the energy efficiency of servers. First, the variation of energy consumption with the performance of servers is taken into account; second, data locality can be adjusted dynamically according to current network state; last but not least, considering that task-scheduling strategies depend directly on data placement policies, we formulate the problem as an integer bi-level programming model. In order to solve the model efficiently, specific-design encoding and decoding methods are introduced. Based on these, a new effective multi-objective genetic algorithm based on MOEA/D is proposed. As there are usually tens of thousands of tasks to be scheduled in the cloud, this is a large-scale optimization problem and a local search operator is designed to accelerate convergent speed of the proposed algorithm. Finally, numerical experiments indicate the effectiveness of the proposed model and algorithm. 相似文献
8.
Liang‐Wei Zheng Gwo‐Long Li Mei‐Juan Chen Chia‐Hung Yeh Kuang‐Han Tai Jian‐Sheng Wu 《ETRI Journal》2013,35(3):469-479
This paper proposes an efficient computation‐aware mode decision and search point (SP) allocation algorithm for spatial and quality scalabilities in Scalable Video Coding. In our proposal, a linear model is derived to allocate the computation for macroblocks in enhancement layers by using the rate distortion costs of the base layer. In addition, an adaptive SP decision algorithm is proposed to decide the number of SPs for motion estimation under the constraint of the allocated computation. Experiment results demonstrate that the proposed algorithm allocates the computation resource efficiently and outperforms other works in rate distortion performance under the same computational availability constraint. 相似文献
9.
在无线传感网络中,传感节点是能量受限的,因此能耗在这种网络显得十分重要,关系到整个网络的生命周期与性能.而无线传感网络的MAC协议对节点的节能有着重要的作用.本文在已有研究的基础上加以改进形成一种更有效的感知流量信息进行节能的MAC协议.该协议同S-MAC协议一样也是采用睡眠的机制,但不同于S-MAC的是该协议中监听与... 相似文献
10.
Bo Rong Rose Qingyang Hu Wei Li Yi Qian 《International Journal of Communication Systems》2011,24(9):1136-1149
Multiuser orthogonal frequency division multiplexing (OFDM) is a promising technology to achieve high uplink/downlink (DL) capacities in the next generation broadband wireless networks such as WiMAX (Worldwide Interoperability for Microwave Access). In this paper, we investigate the DL adaptive power allocation (APA) in multiuser OFDM system from the perspective of cross‐layer design. Specifically, we formulate APA as an optimization problem with the traffic profile of each user asit a priori knowledge. To solve the optimization problem, we develop a fairness‐constrained optimal prioritized effective throughput (PET) strategy and the corresponding iterative algorithms, aiming at balancing the prioritized effective throughput and the linear or logarithmic user satisfaction‐based fairness. Simulation results show that our proposed APA optimization approach can achieve satisfying performance. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献