高校科研能力的协同IWD粗糙集-块神经网络评估模型

针对高校科研能力评估过程中存在的多因素、高非线性特点,经典评估模型主观性较强,导致模型评估准确性不高的问题,提出基于协同智能水滴算法IWD和粗糙集块神经网络RBNN的高校科研能力评估模型。首先,引入智能水滴算法,并针对传统智能水滴算法固定旁域搜索范围不利于提升算法搜索效率的问题,提出一种局部空间自动缩放算法LSAS,该算法根据当前种群最优个体,自动调整下一步搜索空间大小,对进化过程进行指导,提高算法的进化效率;其次,基于粗糙集理论对高校科研能力数据进行特征预处理,简化数据计算量;最后,对块神经网络和粗糙集参数进行编码,并对高校科研能力模型进行评估。仿真结果表明,此评估模型具有较高的准确性和较快的计算效率。     

Game‐Based Valley‐Fill Charging Coordination for Large‐Population Plug‐in Electric Vehicles

Charging coordination of large‐population autonomous plug‐in electric vehicles (PEVs) in the power grid can be formulated as a class of constrained optimization problems. To overcome the computational complexity, a game‐based method is proposed for the charging problems of the PEV population, which is composed of homogeneous subpopulations, such that individuals update their best charging strategies simultaneously with respect to a common electricity price determined by the total demand. To mitigate the oscillation behavior caused by the greedy behavior for the cheap electricity by individuals, a deviation cost is introduced to penalize against the deviation of the individual strategy from the average value of the homogeneous subpopulation. By adopting a proper deviation cost and following a best strategy update mechanism, the game systems may converge to the socially optimal valley‐fill Nash equilibrium. Simulation examples are studied to illustrate the results.     

AMI通信网络中微功率无线通信的性能测试技术及系统研究

微功率无线通信是高级量测体系的主要通信方式之一,各厂家的通信模块性能不一,测试技术尚未形成统一的规范;设计了微功率无线通信的测试系统,由射频性能测试系统和协议一致性分析系统组成;系统采用屏蔽测试箱、多功能电磁波小室、综合测试分析仪、误码分析仪、标准协议信号源等模块组成,屏蔽箱对800 MHz频率以下的无线电信号有超过70dB的抑制,可以提供相对纯净的无线电暗室环境,减少外界无线电波的干扰;测试频率范围为30MHz~1GHz,提供66个测试频点,测试频率误差小于2ppm,误码测试精度小于0.001%,功率测试精度(闭环)为5%(0.2dB);实现了在实验室情况下对微功率无线网络性能的全面测试和评估,具备很好可操作性、便利性和可复现性。     

自主-合作教学模式在C＋＋程序设计教学改革中的应用

针对在C＋＋程序设计课程教学中存在的问题,结合对自主-合作教学模式的研究,提出以自主学习教学模式贯穿教学始终;案例驱动的精讲与泛读相结合;手写程序与机器调试相结合;自主学习与合作学习相结合的教学新思路。并阐述了上述方法在教学改革实践中的具体应用及效果。     

Contention-based forwarding with multi-hop connectivity awareness in vehicular ad-hoc networks

Recent vehicular routing proposals use real-time road traffic density estimates to dynamically select forwarding paths. Estimating the traffic density in vehicular ad hoc networks requires the transmission of additional dedicated messages increasing the communications load. These proposals are generally based on unicast sender-based forwarding schemes. The greedy nature of sender-based forwarding can result in the selection of forwarders with weak radio links that might compromise the end-to-end performance. To overcome these limitations, this paper presents TOPOCBF, a novel contention-based broadcast forwarding protocol that dynamically selects forwarding paths based on their capability to route packets between anchor points. Such capability is estimated by means of a multi-hop connectivity metric. The obtained results demonstrate that TOPOCBF can provide good packet delivery ratios while reducing the communications load compared to unicast sender-based forwarding schemes using road traffic density estimates.     

A suboptimal joint bandwidth and power allocation for cooperative relay networks＂ a cooperative game theoretic approach

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.     

Fair relay selection in decode-and-forward cooperation based on outage priority

The opportunistic cooperation schemes,where only the "best" relay is selected to forward the message,have been widely investigated recently for their good performance in terms of outage probability.However,the unfair selections of relays may cause unbalance power consumptions among relays,which reduces the lifetime of energy constrained networks.In this paper,we introduce a novel concept of outage priority based fairness(OPF),aiming at improving the selection fairness among relays appropriately without outage performance deterioration.Then,a cooperation scheme is proposed to meet this concept,and corresponding theoretical analysis is also provided.Afterward,based on OPF,the achievable upper bound of the fairness is derived,and an optimal cross-layer designed scheme is also provided to achieve the bound.Numerical simulations are carried out finally,which not only validate the theoretical analysis,but also show that taking advantages of the proposed schemes,the fairness among all relays,as well as the network lifetime,can be greatly improved without any loss of outage performance,especially in high SNR regime.     

灾害中生活类物资的供应分析——以汶川地震重灾区物资供应为例

救灾生活类物资在供应中面临着优化运输路线、降低运输成本、缩短运输时间3个难题。文章采用相关机会多目标规划模型,以汶川地震为例,总结并完善了自然灾害救助中的多物资的协作供应模式,为突发性重大灾害中多物资的协作供应的组织、实施、管理提供参考支持。     

浅谈计算机网络与数据通信的发展

计算机网络与数据通信,给人们的生产生活提供了极多的便利和帮助;已成为信息技术和电信技术的主要发展方向之一。本文简单回顾了计算机网络与数据通信发展的历史,着重分析了其现状,并展望了未来的发展趋势。     

卫星通信TCP特性及改进

文章就卫星通信TCP性能改进进行了研究,分析了船载卫通站卫星通信通过TCP协议传播的一些不利于工作效率的特性,针对部分特性提出了改进方法,并进行了简单的测试,TCP协议作为一种可靠的通信协议,本身采取了一些保护数据安全传输的措施,但是这些措施往往是应用于有线网络,并不能很好地适应船载卫通站的通信保障需求。本文提出的改进方法主要是采用分析数据包丢失现象改进TCP传输的拥塞控制和慢启动策略。