基于遗传算法的RLV再入轨迹优化设计

飞行器再入轨迹优化是一类最优控制问题。传统的优化方法存在初始值敏感问题。利用小生境技术和精英方法改进适应值共享拥挤遗传算法,并将其用于RLV再入轨迹优化设计。以终端时间固定的空间最小控制能量再入轨迹和终端时间自由的平面最小热载再入轨迹为例,详细讨论了遗传算法用于再入轨迹优化设计所需要解决的一些关键问题。仿真结果表明提出的方法能够较快地搜索到全局最优解,对初始猜测值不敏感,能够方便用于RLV的再入轨迹方案选择和优化设计。     

改进的聚类算法及在复杂大群体决策中的应用

针对现有FCM聚类算法中存在的局部极值和伸缩性较差等问题,提出了基于全部最小连通支配集算法(minimum connected donating set algorithm,MCDSA)的改进的聚类算法(minimum fuggy C-means,MF-CM)。用改进的聚类算法MFCM辅助复杂大群体决策(complex huge group-decision,CHGDS),定义了群体偏好矢量和群体一致性指标,提供了一种新的解决CHGDS中群体决策的理论和方法,并通过实验证明了该方法的有效性和稳定性。还提供了基于属性加权进化的群体一致性决策机制新思路。     

基于对角递归神经网络盲均衡算法的研究

提出了一种基于对角递归神经网络的盲均衡算法。利用对角递归神经网络结构简单、计算量少的优点,结合传统的恒模盲均衡算法定义了代价函数,用最速梯度下降法推导出了其算法迭代公式。计算机仿真表明,该算法收敛速度较快,误码率较小。     

Research and Application on Web Information Retrieval Based on Improved FP-Growth Algorithm

0 IntroductionThe useful texts information in the Web is analyzed bythe method of Web information retrieval according tothe requirement of the user . To get the information of citingtexts and relative key words fromthe Web,we can searchforlots of correlativeinformation data storedinthe Web databaseby Webinformationretrieval .This paper appliedthe method-ology of data mining to Web information retrieval since thepurpose of data miningisto discover thefrequent patternfromthe Web.Alot of studi…     

A Parallel Genetic Simulated Annealing Hybrid Algorithm for Task Scheduling

0 IntroductionGrid computingis a hot topic inthe current internet research,and a developing direction of the parallel and distributedprocess[1 ,2].Since the task scheduling in grid computing faces aNP-hard problem[3];it has drawn attention from many scholarsand become the focusinthe field of the current grid computing re-search.In recent years , two global random and opti mal algorithmhave been widelystudiedandappliedinthefield of the gridcompu-ting research: GA(Genetic Algorithm) and SA( …     

Dynamically Reconfigurable Encryption System of the AES

Reconfigurable computing has grown to become an important and large field of research, it offers advantages over traditional hardware and software implementations of computational algorithms. The Advanced Encryption Standard （AES） algorithm is widely applied in government department and commerce. This paper analyzed the AES algorithms with different cipher keys, adopted a novel key scheduler that generated the round key real-time, proposed a dynamically reconfigurable encryption system which supported the AES algorithm with different cipher keys, and designed the architecture of the reconfigurable system. The dynamically reconfigurable AES system had been realized on FPGA. The result proves that the reconfigurable AES system is flexible, lower cost and high security level.     

Specification and Verification for Semi-Structured Data

Tree logic, inherited from ambient logic, is introduced as the formal foundation of related programming language and type systems, In this paper, we introduce recursion into such logic system, which can describe the tree data more dearly and concisely. By making a distinction between proposition and predicate, a concise semantics interpretation for our modal logic is given. We also develop a model checking algorithm for the logic without △ operator. The correctness of the algorithm is shown. Such work can be seen as the basis of the semi-structured data processing language and more flexible type system.     

基于光突发控制包缓存的批调度算法

在光突发交换（OBS）网络中，数据信道调度算法是提高网络性能的重要措施之一。提出了一种基于光突 发控制包（BCP）缓存的批调度算法M其主要思想是：对到达的突发控制包进行缓存M当设定的最大缓冲时间到了， 首先按照业务的优先级，再按照突发到达顺序对缓冲区中的BCP进行批调度处理，并采用LAUC-VF来调度数据 突发（DB）该算法通过缓冲较多的BCP，获得更多的突发信息，有利于优化调度DB，从而降低了突发丢失率。仿 真结果表明：该算法具有比LAUC-VF还要低的DB丢失率，并能有效支持QoS。     

OBS网络中IP分组长度分布对业务流自相似性的影响

近年来，大量研究发现，网络流量呈现自相似性，自相似会导致数据分组延迟增大，丢包率增加，网络性能 恶化。着重论述了在OBS固定时间汇聚算法下，用于汇聚成突发数据分组的IP分组长度对业务流自相似影响的 问题。突发数据分组的汇聚算法是光突发交换的关键技术之一，其中，固定时间汇聚（FAP）算法可以平滑流量、降 低流量自相似性。用于汇聚成突发数据分组的IP分组，其自身长度对固定汇聚（FAP）算法的流量整形有一定影 响。仿真结果表明，存在最佳汇聚时间门限，能极大地降低业务流自相似程度，且最佳汇聚时间门限与IP分组长     

季节性商品的促销定价模型与算法

研究了季节性商品在促销前提下的定价问题.在综合考虑季节性商品的销售特点、销售折扣率、商品库存、商品周期衰退、商品价格等问题的基础上,建立了以利润损失最小为目标的动态定价模型,以商家需处理的货物量为约束条件,基于改进遗传算法和粒子群算法,找到了成本最优的商品定价.并通过仿真,分析了商品定价对利润损失的影响,为大中型企业的促销决策提供了重要依据.