基于双极偏好控制的多目标粒子群优化算法

考虑双极偏好信息对粒子群的控制作用,提出一种使用双极偏好——正偏好和负偏好引导粒子群向 Pareto 前沿偏好区域进化的方法．根据TOPSIS 决策法思想,将外部种群粒子与正负偏好点的相对贴近度排序作为 外部种群管理和全局最优解更新策略;根据贴近度值确定解集的分布度;选取6 种不同类型的多目标测试函数进行 算法模拟,从世代距离、空间测度和超体积测度3 个指标与基于单极偏好的多目标粒子算法进行性能比较．结果显 示,基于双极偏好控制的多目标粒子群算法的收敛性和综合性能更优秀．     

Exponential stability for uncertain neutral systems with Markov jumps

This paper deals with the global exponential stability problems for stochastic neutral Markov jump systems （MJSs） with uncertain parameters and multiple time-delays. The delays are respectively considered as constant and time varying cases, and the uncertainties are assumed to be norm bounded. By selecting appropriate Lyapunov-Krasovskii functions, it gives the sufficient condition such that the uncertain neutral MJSs are globally exponentially stochastically stable for all admissible uncertainties. The stability criteria are formulated in the form of linear matrix inequalities （LMIs）, which can be easily checked in practice. Finally, two numerical examples are exploited to illustrate the effectiveness of the developed techniques.     

基于动态贝叶斯网络的社交圈归属匹配模型

为了帮助社交网中新成员寻找与之最为合适的社交圈,尝试采用动态贝叶斯网（DBN）理论解决社交网分析应用中成员（节点）与社交圈（集合）的匹配问题。将圈内成员个人的多项兴趣爱好程度作为描述社交圈基本属性的特征向量,对每一类圈子建立了带有辅助信息形式的DBN模型,求解最大输出概率即为最佳匹配对象。结果表明,在客观测试和主观评价两方面,该模型都收到了较为满意的结果。     

阵列水声信号采集系统设计

提出了一种新型大规模阵列水声信号采集系统设计方法。该设计基于数据流驱动设计思想,利用FPGA实现了高速LINK口,同时在数据传输中采用独特的两级缓冲结构,因而系统拓扑结构灵活,数据吞吐率高,同时具备同步性能好,扩展性强的特点。     

酒石酸还原Cu(Ⅱ)制备多种形貌Cu_2O晶体及形成机理

以CuSO_4·5H_2O为原料,KOH为添加剂,酒石酸为还原剂,在水热条件下通过调整相关的实验参数,制备了一系列不同形态的Cu_2O微-纳米晶体及三维十字形枝晶。采用XRD、SEM等手段对不同形态的Cu_2O晶体进行了表征,探讨了不同因素变化对Cu_2O晶体形态的影响。分析认为,晶体生长过程控制了晶体的具体形貌和大小,Cu_2O晶体显露的单形晶面随晶体生长条件的变化而不同。在低温、弱碱性、高浓度溶液中有利于形成八面体形态的Cu_2O晶体,而菱形十二面体单形晶面在高温、强碱性、低浓度溶液中形成的晶体中显露的面积有所增大。     

超声冲击诱发表面纳米化及其对表面完整性的影响

采用不同超声冲击参数处理SMA490BW钢,研究了冲击后试样在低、高倍下的微观组织特征、残余应力及硬度分布等表面完整性能的变化。实验结果表明,经过超声冲击表面处理后,样品表面层晶粒细化为纳米晶,平均晶粒尺寸约为30nm;并在试样表层引入残余压应力,数值最大约为255.5MPa;超声冲击对SMA490BW钢表面能够起到明显的强化作用,与未经处理的试样相比,处理后试样表面硬度最大提高了约66.7%。超声冲击强化处理改善SMA490BW钢的表面完整性的效果与冲击电流、冲击时间之间的关系不遵循单调变化规律,超声冲击参数为20min/1.5A时,试样具有较好的表面完整性,冲击影响层深度约为320μm。     

Preliminary Study on Quantitative Research Methods of Discussion-based Teaching: CAD/CAM Course

Computer-aided design and manufacturing,or CAD/CAM,in a narrow sense,is the use of a computer for component design and machining. As a specialized course for students,CAD/CAM course is a required course for undergraduates majoring in mechanical engineering and related engineering majors and also the core technical skills to be mastered during the undergraduate study. Based on the teaching practices of CAD/CAM course,this paper tries to introduce the discussion-based method in curriculum design and the implementation of the course,and enhance the interaction between teachers and students through using new information interaction tools such as We Chat group and course homepage to stimulate students' interest,and also expand the learning space and time. Thus,the problems students have will be solved in real time. In this study,for the first time,the statistical methods are used to record detailed the speaking time,keywords and the frequency of teachers and students' interaction,and also carries out quantitative analysis in order to explore the interactive patterns between teacher and students in discussion-based teaching,so as to improve communication and learning efficiency between teacher and students. Meanwhile,this paper also discussed the advantages and the disadvantages of using discussion-based teaching in the hope that it can provide reference for the following discussion-based teaching of CAD/CAM course in mechanical or related engineering majors.     

Monitored high-dose azathioprine treatment reduces acute rejection episodes after renal transplantation

A novel complex mutation consisting of a small deletion/insertion (3958del5ins4) was found in the breast cancer-1 gene (BRCA-1) in three unrelated French breast and/or ovarian cancer families. These mutations occurred at the same nucleotide position of the 3' end of exon 11. The wild-type sequence, CTCAG, was deleted and replaced by AGGC in the three families. The consequence is the generation of a stop codon, TAG, resulting in a truncated protein. We propose two different mechanisms to explain the generation of this complex mutation: (i) the simultaneous occurrence of a deletion and an insertion in a stem-loop structure and (ii) the abortive integration of a human transposable element (Tigger 1) that deleted 5 nucleotides and inserted a 4-nucleotide "scar", corresponding to the 5' extremity of the transposon.     

基于无线网络技术的燃气集抄系统设计

针对燃气行业人工抄表费时费力等问题,提出一种基于GPRS和无线多跳网络技术的燃气无线抄表系统,在分析传统抄表系统的结构以及传输方式优缺点的基础上介绍了系统的总体结构、工作原理以及各部分组成和功能。采用计算机网络和数据库等技术,使得该系统具有功能强大、使用方便、可扩展性好等特点,可实现对整个燃气输配系统的监控,有效提高燃气公司的管理水平和服务效率。     

CAN总线网络测试研究

介绍了CAN总线网络开发方法,搭建了CAN总线集成开发测试环境,对实际网络进行了测试,给出了位定时参数计算方法,比较了不同模拟终端电阻下的总线的报文正确率和总线负载率等性能指标.