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71.
校园网已成为高校教育、科研、行政办公的重要工具和载体。高校师生对校园网的应用提出了较高的要求。但是目前大部分高校的网络速度并不是太理想,网络结构和性能有待进一步提高。本文对河南财经政法大学校园网的网速及应用进行了分析,提出了在不增加带宽的前提下改善网速的方法和控制策略。  相似文献   
72.
曹建峰 《物联网技术》2013,(8):82-84,87
在传统数解法交通绿波带算法的基础上,根据道路情况实行分段,对传统数解法模型进行了优化。优化后的绿波带协调算法运算量得到较大减少,以便其利用EXCEL表即可得到较为准确的交通绿波带控制参数,以适合手持嵌入式设备的处理,并在感知车流的基础上对实时绿波带控制进行了一定的探索。  相似文献   
73.
In this paper, a processor allocation mechanism for NoC-based chip multiprocessors is presented. Processor allocation is a well-known problem in parallel computer systems and aims to allocate the processing nodes of a multiprocessor to different tasks of an input application at run time. The proposed mechanism targets optimizing the on-chip communication power/latency and relies on two procedures: processor allocation and task migration. Allocation is done by a fast heuristic algorithm to allocate the free processors to the tasks of an incoming application when a new application begins execution. The task-migration algorithm is activated when some application completes execution and frees up the allocated resources. Task migration uses the recently deallocated processors and tries to rearrange the current tasks in order to find a better mapping for them. The proposed method can also capture the dynamic traffic pattern of the network and perform task migration based on the current communication demands of the tasks. Consequently, task migration adapts the task mapping to the current network status. We adopt a non-contiguous processor allocation strategy in which the tasks of the input application are allowed to be mapped onto disjoint regions (groups of processors) of the network. We then use virtual point-to-point circuits, a state-of-the-art fast on-chip connection designed for network-on-chips, to virtually connect the disjoint regions and make the communication latency/power closer to the values offered by contiguous allocation schemes. The experimental results show considerable improvement over existing allocation mechanisms.  相似文献   
74.
水库补偿效益分配问题研究   总被引:1,自引:0,他引:1  
水库补偿效益分配的步骤:一是确定水库补偿效益的施益方和受益方;二是计算水库补偿效益值;三是选择科学合理并能使各方较满意的分配方法.在分析水库补偿效益不确定性、可变性和博弈性的基础上,探讨了梯级水库串联式发电和并联式水库发电补偿效益影响因子的识别方法.水库补偿效益的分配方法主要有多目标综合分析法、模糊综合评判法、熵权法、离差平方法等,但都存在不足,需要进一步研究完善.  相似文献   
75.
对深圳市茅洲河流域工业生产、农业灌溉、城市绿地浇灌、道路广场浇洒以及居民冲厕等方面的再生水需求进行分析,建立包括4个再生水厂、35个再生水用水片区的再生水优化配置模型,并运用LINGO求解其全局最优解。结果表明:①茅洲河流域再生水厂的生产能力为59.4万m3/d,仅能满足该流域污水处理需求的51.7%;②农业灌溉、工业回用、城市绿地浇灌、道路广场浇洒、居民冲厕等行业使用再生水的边际收益分别为3.7元/m3、21.6元/m3、4.1元/m32、.1元/m3、1.3元/m3。  相似文献   
76.
以水功能区为基本单元的流域水资源配置方法探讨   总被引:1,自引:0,他引:1  
以水功能区为基本单元,以水功能区管理办法和分水协议为基础,以滦河流域为研究对象,综合考虑上下游工农业用水和生态环境用水,对各水功能区的水资源潜在利用量和实际可利用量确定方法进行分析,探讨滦河流域水资源配置和合理利用方案,为水资源的合理开发利用提供参考依据。  相似文献   
77.
In this article, we investigate uplink resource allocation in orthogonal frequency division multiple access (OFDMA) systems that use distributed antennas. The multiple distributed receiving antennas motivate us to exploit the spatial diversity to maximize the achievable rate of the system. Given constraints on the subcarrier allocation and the power limit of each user equipment (UE), a mixed-integer optimization problem is formulated. We first propose a centralized greedy algorithm to find the maximum achievable rate of the system. Then a heuristic algorithm is proposed that can be implemented in a distributed manner. Simulation results show that the heuristic algorithm can approximately achieve the maximum achievable rate of the system and result in significant system performance improvement over the approach assigning one user to each subcarrier.  相似文献   
78.
This paper presents a joint relay selection and power allocation scheme for amplify-and-forward two-path relaying networks,in which diferent relay nodes forward information symbols alternatively in adjacent time slots.Our approach is based on the maximization of the received signal-to-noise ratio under total power consumption by the transmission of the symbol.We show that in spite of inter-relay interferences,the maximization problem has a closed-form solution.Simulation results explicitly indicate that the performance of proposed approach outmatches the existing methods including equal power allocation and one-path relaying.  相似文献   
79.
An innovative dynamically reconfgurable radio-over-fber(RoF)network equipped with an intelligent medium access control(MAC)protocol is proposed to provide broadband access to train passengers in railway high-speed mobile applications.The proposed RoF network architecture is based on a reconfgurable control station and remote access unit(RAU)that is equipped with a fxed flter and tunable flter.The proposed hybrid frequency-division multiplexing/time division multiple access(FDM/TDMA)based MAC protocol realizes failure detection/recovery and dynamic wavelength allocation to remote access units.Simulation result shows that with the proposed MAC protocol,the control station can detect failures and recover and dynamic wavelength allocation can increase the wavelength resource utilization to maintain network performance.  相似文献   
80.
In commercial networks, user nodes operating on batteries are assumed to be selfish to consume their resources (i.e., bandwidth and power) solely maximizing their own benefits (e.g., the received signal-to-noise ratios (SNRs) and datarates). In this paper, a cooperative game theoretical framework is proposed to jointly perform the bandwidth and power allocation for selfish cooperative relay networks. To ensure a fair and efficient resource sharing between two selfish user nodes, we assume that either node can act as a source as well as a potential relay for each other and either node is willing to seek cooperative relaying only if the datarate achieved through cooperation is not lower than that achieved through noncooperation (i.e., direct transmission) by consuming the same amount of bandwidth and power resource. Define the cooperative strategy of a node as the number of bandwidth and power that it is willing to contribute for relaying purpose. The two node joint bandwidth and power allocation (JBPA) problem can then be formulated as a cooperative game. Since the Nash bargaining solution (NBS) to the JBPA game (JBPAG) is computationally difficult to obtain, we divide it into two subgames, i.e., the bandwidth allocation game (BAG) and the power allocation game (PAG). We prove that both the subgames have unique NBS. And then the suboptimal NBS to the JBPAG can be achieved by solving the BAG and PAG sequentially. Simulation results show that the proposed cooperative game scheme is efficient in that the performance loss of the NBS result to that of the maximal overall data-rate scheme is small while the maximal-rate scheme is unfair. The simulation results also show that the NBS result is fair in that both nodes could experience better performance than they work independently and the degree of cooperation of a node only depends on how much contribution its partner can make to improve its own performance.  相似文献   
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