A constructive approach to minimal realization problem of 2D systems

Unlike in the 1D case, it is not always possible to find a minimal state-space realization for a 2D system except for some particular categories. The purpose of this paper is to explore a constructive approach to the minimal Roesser model realization problem for a class of 2D systems which does not belong to the clarified categories. As one of the main results, a constructive realization procedure is first proposed. Based on the proposed procedure, sufficient conditions and explicit construction for minimal realizations of the considered 2D systems are shown. In addition, possible variations and applications of the obtained results are discussed and illustrative examples are presented.     

Performance index based learning controls for the partial non-regular systems using lifting technique

Deficiencies of the performance-based iterative learning control （ILC） for the non-regular systems are investigated in detail, then a faster control input updating and lifting technique is introduced in the design of performance index based ILCs for the partial non-regular systems. Two ldnds of optimal ILCs based on different performance indices are considered. Finally, simulation examples are given to illustrate the feasibility of the proposed learning controls.     

梦中的香格里拉——平面设计中的自由表现

自由表现——跟随着设计的发展、设计运动的兴起而一起兴衰成败,但从未离开过设计舞台,在当今的设计中更是发挥了它的重要作用和独特的魅力。自由表现在传达功能以及审美价值两方面都发挥着其卓越的功效,自由表现手法形式多样,千变万化,其创造出的视觉效果也是无穷尽的。他宛如空气一般无形地渗透到设计的各个领域,给设计带来生命和活力。惟有自由,才能容纳一切未来的生命!     

基于Max-Flow理论的本体分割算法

本体是语义网的核心部件之一,近来越来越多的研究表明本体能极大地有助于信息处理任务质量和效率的提高.然而,由于领域知识的复杂性,在给应用程序提供强有力的支持的同时,本体自身不可避免地呈现出结构复杂,规模庞大的特点,从而给本体的维护和操作带来了极大的不便.为此,本文提出了一个基于Max-Flow理论的本体分割算法,首先将本体转化成相应的能量图,然后应用Min-Cut图切分算法将其快速划分为紧密联系的模块的集合.获得的实验数据表明此算法能生成较高质量的模块.     

外语类院校《操作系统》课程设置及教学探索

由于学生的生源特征、知识背景和所处大环境的不同,外语类学校中<操作系统>的教学并非易事,是专业教学中的难点.为了能够让学生掌握操作系统的有关知识,应正视与理工院校存在的差异和距离,在课程设王、教学方法教学组织、实践环节等方面进行了探索,取得了一定效果.     

考虑虚拟电厂可信容量的新能源电力系统容量市场出清模型

随着风电和光伏发电装机规模快速增长,系统出现了发电容量充裕度不足的问题。为确保电力系统中的充足发电容量,需要引入容量市场机制。相比于大型火电机组的长建设周期和高投资成本,分布式可调节资源聚合的虚拟电厂（virtual powerplant,VPP）建设周期短、投资小、见效快,是为系统提供发电容量的有效资源。因此,构建了虚拟电厂可信容量（unforcedcapacity,UCAP）计算方法并提出一种考虑虚拟电厂可信容量的新能源电力系统容量市场出清模型。虚拟电厂可信容量计算模型考虑了其功率、能量以及运行特性。容量市场出清模型在考虑发电侧风电、光伏、传统机组的基础上,增加用电侧虚拟电厂参与市场。容量市场出清模型中考虑了高峰容量需求、基本容量需求、电能需求、谷荷需求、爬坡功率需求等系统约束。最后通过算例分析了虚拟电厂可信容量、市场容量总需求量以及新能源装机容量对市场出清结果的影响,验证了本文虚拟电厂可信容量计算方法以及容量市场出清模型的有效性。     

增材制造技术在电机中的应用综述

增材制造技术(即3D打印)因具有高设计自由度、高材料利用率、高成形效率和精度等优势,逐渐成为高效轻质高功率密度电机设计与制造的研究热点。该文旨在对3D打印电机的性能及其应用作系统性综述。首先,对3D打印电机的发展脉络进行简要概括。其次,分别对3D打印铁心、磁钢、绕组,以及散热和机械支撑结构的研究现状进行总结,并与传统工艺加工的样件进行性能对比。随后,介绍了适用于增材制造的结构设计方法——拓扑优化。最后,根据目前的研究情况归纳了3D打印电机未来的发展趋势和面临的挑战。     

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.     

自组网环境下基于组合公钥的分布式密钥管理

结合组合公钥密码体制和秘密共享思想,针对移动自组网环境,提出了一种分布式密钥管理方案.从系统初始化、管理平台构建、节点公私钥生成、私钥矩阵份额更新等4个方面进行了详细描述,并给出了具体实施方法.分析表明,该方案具有安全性高、扩展性强、计算量小、适用性好的特点,特别适合移动自组网环境.