Trust-based group services selection in web-based service-oriented environments

Multi-agent technologies have been widely employed for the development of web-based systems, including web-based e-markets, web-based grid computing, e-governments and service-oriented software systems. In these service-oriented systems, service provider agents and service consumer agents are autonomous and rational entities, which can enter and leave the environments freely. For simplicity, we use terms ‘provider’ and ‘consumer’ to represent this two types of agents. How to select the most suitable service providers according to a service request from a consumer in such an open environment is a very challenging issue. In this paper, we propose an innovative trust model, called the GTrust model, for service group selection in general service-oriented environments. In the GTrust model, the trust evaluation for a service group is based on the functionality coverage of the group, the dependency relationships among individual services in the group, the ratings of individual services on the attributes of the service request and a similarity measurement of the extent to which reference reports can reflect the service request in terms of the priority distribution of attributes. The experimental results and analysis demonstrate the good performance of the GTrust model on the service group selection in service-oriented environments.     

Robust Adaptive Neural Control for a Class of Time‐Varying Delay Systems with Backlash‐like Hysteresis Input

This paper proposes a robust adaptive dynamic surface control (DSC) scheme for a class of time‐varying delay systems with backlash‐like hysteresis input. The main features of the proposed DSC method are that 1) by using a transformation function, the prescribed transient performance of the tracking error can be guaranteed; 2) by estimating the norm of the unknown weighted vector of the neural network, the computational burden can be greatly reduced; 3) by using the DSC method, the explosion of complexity problem is eliminated. It is proved that the proposed scheme guarantees all the closed‐loop signals being uniformly ultimately bounded. The simulation results show the validity of the proposed control scheme.     

Consensus in second‐order Markovian jump multi‐agent systems via impulsive control using sampled information with heterogenous delays

This paper investigates the consensus problem of second‐order Markovian jump multi‐agent systems with delays. Both network‐induced random delay and node‐induced state delay are considered, where the network‐induced random delay, subjected to a Markov chain, exists in the switching signal and the node‐induced state delay, related to switching topologies, is heterogeneous between any two linked agents. In order to reduce communication and control energy, an impulsive protocol is proposed, where each agent only can get delayed relative positions to neighbors and the velocity of itself at impulsive instants. By performing three steps of model transformation and introducing a mapping for two independent Markov chains, the consensus problem of the original continuous‐time system is equivalent to the stability problem of a discrete‐time expand error system with two Markovian jumping parameters and a necessary and sufficient criterion is derived. A numerical example is given to illustrate the effectiveness of the theoretical result.@@@@This work is supported by the National Natural Science Foundation of China under Grants 61374171, 61572210, and 51537003, the Fundamental Research Funds for the Central Universities (2015TS030), and the Program for Changjiang Scholars and Innovative Research Team in University (IRT1245).     

新型雨水径流计量用复合堰的设计及率定

针对其他流量计量方法不易监测雨水径流流量的问题,提出一种新型复合堰,用于测量雨水径流流量,新设计的堰由下部三角形堰和上部矩形堰复合而成。根据不同重现期下的雨水峰值流量,确定堰的量程和基本尺寸。通过率定试验,得出不同水头下的流量系数以及流量-水头关系曲线。新型复合堰不仅可以精确测量小流量,而且对大流量也可有效测量,具有较高的量程比和较大的泄流能力。     

面向5 G无线通信系统的关键技术综述

对未来无线通信系统的几种潜在的关键通信技术,如异构网络、大规模多输入多输出(MIMO)通信、绿色通信和毫米波通信,给出了较详尽的论述与讨论。首先简要介绍了未来无线通信网络结构的异构化变化所引起的复杂干扰信号的出现及能源消耗增加问题。介绍了大规模MIMO通信技术的优点,大规模MIMO通信的研究现状与研究难点。详尽叙述了分别以频谱效率、能源效率和资源效率最大化为目标的绿色无线通信传输优化问题的解决方案。最后,给出了进一步解决频谱稀缺问题的毫米波无线通信系统的混合波束成形的方案。     

基于元胞自动机的多车道机非混合道路交通流

车辆的行驶受到本车道以及邻近车道前后邻近车辆的影响,在城市交通中机非混合对车辆行走的影响尤为复杂。通过研究路段上机非混合通行交通流的本质特性,综合考虑非机动车对机动车换道规则及加减速规则的"摩擦"和"阻滞"干扰影响,建立描述路段混合通行道路交通流的元胞自动机(CA)模型,从不同的机非混合比例下道路交通流的流量、速度变化情况,流量与车辆到达率关系,交通流相位相变等方面仿真模拟混合交通流的机非干扰机理。     

基于B/S结构的考勤系统设计

在分析考勤系统需求的基础上,结合实际学生考勤信息录入与汇总的特点,设计了基于B/S结构的课堂考勤系统。应用该系统可方便地进行学生考勤信息的录入、修改与管理,并可进行考勤信息的自动汇总。系统依据权限实现了角色分类,可按角色登录及查询具体的考勤信息,并可进行学生考勤信息的汇总和导出,提高了工作效率。