基于BP神经网络的中学考试成绩分类*

针对中学考试成绩,具体详细地设计一种应用于BP神经网络成绩分类器,用BP算法对网络进行有效地训练,经过测试BP神经网络成绩分类器可确定,该方法有效且有很好的分类效果。用改进的BP算法对网络进行训练,使网络很快得到收敛,解决了一般方法收敛慢的缺陷。     

南京玄武湖景区综合整治之探索与思考

以南京玄武湖环境第四次综合整治为背景,论述了在综合整治过程中进行整治定位和具体建设实施的经验,并且总结了由此而带来的景观建设发展的思考,为今后类似景区的整治提供了参考。     

Study of TSP based on self-organizing map

Self-organizing map （SOM） proposed by Kohonen has obtained certain achievements in solving the traveling salesman problem （TSP）.To improve Kohonen SOM,an effective initialization and parameter modification method is discussed to obtain a faster convergence rate and better solution.Therefore,a new improved self-organizing map （ISOM） algorithm is introduced and applied to four traveling salesman problem instances for experimental simulation,and then the result of ISOM is compared with those of four SOM algorithms：AVL,KL,KG and MSTSP.Using ISOM,the average error of four traveling salesman problem instances is only 2.895 0％,which is greatly better than the other four algorithms：8.51％ （AVL）,6.147 5 ％ （KL）,6.555 ％ （KG） and 3.420 9 ％ （MSTSP）.Finally,ISOM is applied to two practical problems：the Chinese 100 cities-TSP and 102 counties-TSP in Shanxi Province,and the two optimal touring routes are provided to the tourists.     

神经网络在组合优化问题中的应用

目的 研究神经网络在组合最优化问题中的应用。方法 通过讨论Ｈｏｐｆｉｅｌｄ神经网络模型,建立最优化问题的计算能量函数。结果和结论 给出组合数字中八皇后问题的计算能量函数,使八皇后问题的解对应计算能量函数的最小值,并用Ｃ语言进行计机模拟,得到其全部解。     

基于PSO-BP神经网络的矢量水听器的DOA估计

利用PSO-BP神经网络,研究了基于矢量水听器阵列的水下声源的波达方向估计。首先对阵列协方差矩阵进行实值化和特征分解,然后将信号子空间的基作为PSO-BP神经网络的输入,并作为样本数据进行训练,以降低PSO-BP神经网络的复杂度。最后将测试样本代入PSO-BP神经网络,成功地进行了DOA估计。仿真实验表明,该方法泛化性能好,解决了输入维数过大的问题,并提高了DOA估计精度,具有较强的工程应用价值。     

沉积间断断面型金矿产出模式及找矿方向——以桂西久隆金矿为例

广西凤山县久隆金矿产出于晚古生代碳酸盐岩隆起边缘,分布于二叠系和三叠系接触带碎屑岩一侧,矿体呈陡立的透镜状、似层状产于断裂中。上二叠统碳酸盐岩与中三叠统陆源碎屑岩之间,发育典型的古岩溶沉积不整合构造,后期断裂构造叠加、复合在不整合面上,形成高龙式微粒型金矿。该矿床以沉积间断面为基础,叠加、复合后期构造,产于沉积间断面之＂上＂的断裂构造带中,以构造为主要控矿因素,沉积间断面为重要控矿因素,受断控与层控等多重因素复合控制,经多期构造活动叠加形成,可称之为沉积间断断面型金矿。滇黔桂＂金三角＂应从不同控制因素和产出模式形成于同一地质作用的背景出发,考虑层控与断控等多重因素复合、叠加对成矿的控制作用,构造叠加、复合部位是寻找复合型矿床、原生矿和深部隐伏矿床的重点。     

改进BP算法在微悬臂梁载荷与挠度关系研究中的应用

针对标准BP算法收敛速度慢和易陷入局部极小值等缺陷,提出了采用弹性BP算法改进标准BP算法,并将此算法应用于单晶硅（100）微悬臂梁加载后载荷与挠度间关系拟合的实验中（实验在Matlab7.0环境下实现）.实验拟合结果表明：在相同载荷下挠度随微悬臂梁梁长的增长而增大,随其宽梁宽的增宽而减少,随其梁数的增多而减少,与理论计算结果相一致.这些表明了BP神经网络在微悬臂梁载荷与挠度关系研究中的适用性.对进一步分析微悬臂梁的可靠性和设计微悬臂梁都具有一定的参考价值.     

藏北红脊山构造混杂岩带南缘猫耳山边界断裂初探

猫耳山边界断裂是红脊山构造混杂岩带的南缘边界,具韧性变形特征,发育以糜棱岩为代表的塑性变形岩石序列。断裂活动复杂,至少可以识别出逆冲、走滑、逆冲3期构造活动。对其变形环境初步分析表明,在挤压体制下,断裂形成半韧性—韧性变形构造域;红脊山构造混杂岩带内蓝闪片岩中蓝闪石^40Ar-^39Ar年龄为213.2±3 Ma,为断裂形成时代。     

An improved ant colony algorithm and its application in optimal routing problem

Ant colony system(ACS),a kind of ant colony algorithm,is an effective way of solving shortest path problem,however,it has some defects.In this paper,ACS is improved for avoiding getting stuck in a local minimum,whose defects mainly include the following two aspects:initial pheromone solution and pheromone updating.In order to learn the advantages of improved ant colony system(IACS),experiments are conducted for some times.First,it is applied to 8 traveling salesman problem(TSP)instances,and compared with three self-organizing map(SOM)algorithms.Then the author analyzes the space complexity and convergence of two algorithms and compares them.Simulation results show that IACS has much better performance in solving TSP,and it has certain theoretical reference value and practical significance.     

P2P文件共享系统中基于用户行为的搭便车抑制机制

In order to inhibit Free Riding in Peer-to-Peer (P2P) file-sharing systems, the Free Riding In-hibition Mechanism Based on User Behavior (IM-BUB) is proposed. IMBUB considers the regularity of user behavior and models user behavior by ana-lyzing many definitions and formulas. In IMBUB, Bandwidth Allocated Ratio, Incentive Mechanism Based on User Online Time, Double Reward Mech-anism, Incentive Mechanism of Sharing for Permis-sion and Inhibition Mechanism of White-washing Behavior are put forward to inhibit Free Riding and encourage user sharing. A P2P file system BITShare is designed and realized under the conditions of a campus network environment. The test results show that BITShare's Query Hit Ratio has a significant increase from 22% to 99% , and the sharing process in BITShare is very optimistic. Most users opt to use online time to exchange service quality instead of white-washing behavior, and the real white-ish-ing ratio in BITShare is lower than 1% . We confirm that IMBUB can effectively inhibit Free Riding be-havior in P2P file-sharing systems.