近似非齐次无偏GM(1,1) 模型的递推解法及应用

针对传统近似非齐次灰建模可能出现参数复数解的问题, 提出无偏灰色GM(1,1) 模型的递推解法, 从而减少由差分方程向微分方程跳跃而导致误差的问题. 给出不同初始条件下非齐次无偏GM(1,1) 模型的递推预测公式,并在此基础上, 将递推公式运用于时间序列分段, 提出基于近似非齐次无偏GM(1,1) 模型的时间序列分段表示方法. 实例结果表明, 所提出的递推模型能够获得较高的拟合精度, 分析结果验证了基于灰色预测模型在时间序列分段表示中的有效性和实用性.

     

一类有限域丢番图方程的解及其应用

对一类有限域线性丢番图方程c≡x+by(mod N)进行了研究,求出了其通解及域中有效解的对数,并证明其能将部分曲线密码方案求解用户私钥的计算量降低为N/z, z为子群<-b>的最小非零元.指出了5个应用该类型方程曲线密码方案,最后以一个环Z_n上广义圆锥曲线多重数字签名方案私钥的求解为例进行说明.     

多参数融合的飞行品质评估模型的建立

目前航空管理机构与航空公司进行飞行品质评估主要是依据经验与简单飞行参数统计数字,这样做难以得出科学、客观的评估结果。基于提升全行业安全保障能力和运行品质的需求,研究了利用计算机技术对飞行品质进行综合评估的方法。选取了理想值逼近法作为飞行品质综合评估的手段,结合波动通道模型作为飞行品质评估的理论基础,基于提出的飞行品质评估模型对飞行品质评估系统进行了设计。对真实的飞行参数数据建立综合评估模型,同时考察多次航班的多个飞行参数,给出综合的飞行品质评估结论,为飞行评估、训练提供理论基础和科学的评判方法。     

移动支付安全性问题研究

移动支付是允许移动用户利用无线通信技术,使用其移动终端对所消费的商品或服务进行账务支付的一种服务方式。在移动电子商务迅速抢占市场的同时,作为移动电子商务重要组成部分的移动支付近年来发展如火如荼。本文通过对移动支付相关概念的介绍,分析了目前移动支付存在的安全问题,提出了一些解决办法。     

基于无线传感器网络的飞行器测控通信系统测量方案设计

针对目前航天飞行器测控通信系统测量参数种类和数量不断增加,系统可靠性要求越来越高,同时系统重量及设备体积约束日益严格的问题,提出了采用基于无线传感器网络的飞行器测量方案,方案重点从节点配置、时间同步、网络拓扑及能源供应等方面进行阐述和分析,最后给出了应解决的关键技术攻关方向。     

A note on semidefinite relaxation for 0-1 quadratic knapsack problems

We investigate in this note solution properties of semidefinite programming (SDP) relaxation for 0-1 quadratic knapsack problem (QKP). In particular, we focus on the issue of uniqueness of the optimal solution to the SDP relaxation for QKP. We first give a counterexample which shows that the optimal solution to the SDP relaxation for QKP could be non-unique. This is in contrast with the case of unconstrained 0-1 quadratic problems. A necessary and sufficient condition is then derived to ensure the uniqueness of the optimal solution to the SDP relaxation for QKP.     

Haar小波求解线性分数阶微积分方程

分数阶微积分方程的应用逐渐受到广大研究者的重视.论文以Haar小波基函数来逼近线性分数阶微积分方程,通过数值算例的数值解与精确解进行比较,结果表明论文方法是有效的且具有较高的精度.     

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.     

智慧安居解决方案研究

智慧城市建设如火如荼地开展,作为民生类代表应用的智慧安居成为各地智慧城市建设的重点.本文从智慧安居内涵和需求评估入手,重点对智慧安居解决方案、关键成功要素以及实施建议展开讨论,以期给智慧安居实施提供参考借鉴.