基于USB和构件的嵌入式电子测量工作站设计

介绍了基于USB和构件技术,用于大型工程电控中心测试和监控的嵌入式电子测量工作站.该嵌入式电子测量工作站充分利用了PC机强大数据处理能力和USB总线高速数据传输能力,并将基于构件的软件开发方法应用于嵌入式电子测量工作站软件开发,提高了软件开发效率和代码复用率.该嵌入式电子测量工作站具有功能多、体积小、成本低和携带方便等特点.     

部分三值逻辑中Sheffer函数的判定算法

根据部分多值逻辑的完备性理论和部分三值逻辑中准完备集的最小覆盖,给出部分三值逻辑中Sheffer函数的判定算法。     

一种动态未知环境下的机器人路径搜索方法

提出了一种新的路径搜索算法——"触觉感知法"来实现机器人在未知静态与动态环境情况下的路径搜索。该方法不需要提供地图信息,机器人仅收集目标点的距离和方位信息以及通过自带传感器作为触觉器收集周围局部环境信息。机器人以BP神经网络作为决策器,经过训练,可以在静态和动态环境中搜索出一条光滑无碰撞且便捷并能有效避开动态障碍物的运动轨迹。对所提出的方法进行了仿真实验,仿真结果表明算法在静态和动态环境下均能有高效率的路径搜索表现。     

新型Buck-Boost矩阵变换器的双闭环控制策略

为了克服传统矩阵变换器电压传输比低的缺陷, 提出了新型Buck-Boost矩阵变换器, 采用双闭环控制策略进行控制. 介绍了该控制策略的基本原理与设计方法, 对比分析了该控制策略与滑模控制及离散滑模控制的各种特性, 并通过仿真对其控制效果进行了验证. 结果表明: 该控制策略不仅具有比滑模控制和离散滑模控制更加优良的动态性能, 而且还具有更强的谐波抑制能力, 其输出波形的谐波失真度更小, 稳态精度更高, 因而具有更好的应用价值.     

环氧乙烷于控制保险粉合成中的副反应

采用密度泛函理论B3LYP法及自恰等密度PCM模型,在6-311G(d)基组条件中研究环氧乙烷在保险粉生产中参加的主要反应,系统论证环氧乙烷的去向.本文首先分析环氧乙烷于控制硫代硫酸钠含量的热力学、动力学基础及体系中各亲核试剂的反应活性,然后分析环氧乙烷各主要反应的比例关系.理论计算结果与实验结论一致,即硫代硫酸钠消耗的环氧乙烷最多(71.5%),其次是水(17.5%),甲醇(5.0%),亚硫酸氢钠(1.3%).     

基于语义神经网络的汉语表层语义分析

本文提出一种基于语义神经网络的汉语表层语义分析方法。该方法将符号主义和连接主义结合在一起。文中给出了语义神经网络的定义、构造,以及应用于汉语表层语义分析的算法。     

Mobile service oriented architectures for NN-queries

The ever-increasing number of mobile device users has also raised the users’ expectation of mobile services accordingly. This phenomenon has given pressures to the mobile service providers to improve their services in order to stay competitive in the market. The service oriented approach is seen to be a promising scheme for mobile services. This paper presents mobile service oriented architectures for Nearest-Neighbor (NN) queries that are classified into five categories, namely (i) intermittent query mobile services, (ii) continuous query mobile services, (iii) context-aware mobile services, (iv) continuous moving object query mobile services, and (v) data broadcast mobile services. These services incorporate query, location and context-aware services, ontological context model, and broadcast. The proposed architectures are concerned with mobile services for clients on the move requesting services based on their current location, which is arguably the most important feature in a wireless environment. Furthermore, we also discuss the Quality-of-Service (QoS) requirement for mobile services in which request latency time is one of the most important parameters to consider. Some analytical models for query latency measurement are presented and the results are compared with the simulation experiments.     

A new ensemble feature selection and its application to pattern classification

Neural network ensemble based on rough sets reduct is proposed to decrease the computational complexity of conventional ensemble feature selection algorithm. First, a dynamic reduction technology combining genetic algorithm with resampling method is adopted to obtain reducts with good generalization ability. Second, Multiple BP neural networks based on different reducts are built as base classifiers. According to the idea of selective ensemble, the neural network ensemble with best generalization ability can be found by search strategies. Finally, classification based on neural network ensemble is implemented by combining the predictions of component networks with voting. The method has been verified in the experiment of remote sensing image and five UCI datasets classification. Compared with conventional ensemble feature selection algorithms, it costs less time and lower computing complexity, and the classification accuracy is satisfactory.     

一种新的半监督入侵检测算法

针对无监督学习的入侵检测算法准确度不高、监督学习的入侵检测算法训练样本难以获取的问题,提出了一种粒子群改进的K均值半监督入侵检测算法,利用少量的标记数据生成正确样本模型来指导大量的未标记数据聚类,对聚类后仍未能标记的数据采用粒群优化的K均值聚类,有效提高分类器的分类准确性,并实现了对新类型攻击的检测。实验结果表明,算法的整体检测效果明显优于基于无监督学习和监督学习的检测算法。     

一种无线传感器网络的节点自定位方法

节点定位对许多无线传感器网络的应用来说是非常关键的,提出了一种基于移动锚节点的无测距的节点定位算法。此算法建立在Monte Carlo定位算法基础之上,通过利用节点收集到的信息来加速算法中样本的选取,从而提高定位的精度和效率。仿真结果表明,此节点定位技术平均定位精度能达到0.2个通信半径,与其他类似定位技术相比,能够明显提高节点定位精度。