419 research outputs found

    Synthesis,Structures and Properties of Chiral Polymetallic Clusters

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    手性金属簇合物因结合了手性化合物和金属簇合物各自已有的性质,有可能同时呈现出光、电、磁、热和催化当中的两种及其以上的性质,是一类潜在的多功能材料。因此,合理地设计与合成这类具有多功能性质的化合物具有十分重要的意义。然而,目前文献中报道的手性金属簇合物并不多,其性质和应用还有待丰富和拓展。在此背景下,我们进行了以手性金属簇合物的合成、结构与性质研究为题的论文工作。在本论文中,我们探索了3d、3d-4f和4d-4f三个系列的手性金属簇合物的合成与组装规律,解析了它们的单晶结构并主要研究了它们的磁学性质。主要内容如下: 一、手性3d金属簇合物。以单一手性希夫碱H3L1为桥连配体,合成了具有C3...Chiral polymetallic clusters are potential multifunctional materials that display optical, electrical, magnetic, thermal and catalytic properties and/or other synergetic effects, due to the integration of chirality and special properties of metal clusters. Thus, rational design and synthesis of chiral polymetallic clusters are of key importance for the application of the materials. However, not on...学位:理学博士院系专业:化学化工学院化学系_无机化学学号:2052009015331

    Reference and Inheritance:Inspiration from Restorative Justice and Chinese Traditional Legal Culture

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    内容摘要修复性司法作为刑事法制发展的一个新动向,已得到联合国的肯定和推广,并在许多国家进行了试验。在报应性司法和矫正性司法争执不休的同时,传统刑事司法的弊端也日益显现:1、忽略了被害人,无法全面满足被害人的需要;2、只是要求犯罪人消极地接受惩罚,而非积极地进行修复;3、远离社区,未能使社区在犯罪预防中发挥积极作用;4、司法成本高,但预防犯罪收效甚微。修复性司法针对上述不足,从一个全新的视角来审视犯罪和刑事司法问题。从外部特征上看,修复性司法主要由三个支柱支撑:责任、能力和安全。这三个支柱互相配合,能动地、积极地进行犯罪修复工作,并在一些实践项目上取得了成功。当前我国刑事司法改革已经提到议事日程...ABSTRACT Restorative justice is a major development in criminal thinking, which is supported by the United Nation, and restorative justice is developing in many parts of the world. The debate between retributive justice and treatment justice has exposed the defects of traditional criminal justice. Such defects include (1) neglecting victims of crime; (2) only requiring...学位:法学硕士院系专业:法学院法律系_刑法学学号:20020800

    我国零售业态研究

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    改革开放以来零售业作为流通产业的一个重要组成部分在社会再生产过程中的重要 性日益显现出来研究零售业态不但有利于零售企业经济增长方式的转变而且有利于国家 对零售 业进行必要的宏观管理和政策引导同时也有利于企业适应市场因此在现阶段研究我国零 售业态变化趋势也就具有了越来越迫切的现实意义 本文试图在对现代西方有关零售业态变化的理论进行一定介绍的基础上着重阐述 我国的零售业态将发生的变化并针对这些变化从零售业的经营方式和组织形式两个方面 进行初步的探讨提出了对未来零售业的展望 全文共分三章 HTH第一章零售业概述HTSS简要地介绍了零售这个概念和西方有关零售业 态变化的三种理论并分...学位:管理学硕士院系专业:管理学院企业管理系_工商管理硕士(MBA)学号:19951505

    Theoretical and Experimental Investigation of Tm3+-doped Double-clad Fiber Lasers

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    掺铥光纤激光器工作波长可在1.7~2.1μm范围调谐,该波段对人眼安全,且包含大气传输窗口,在激光遥感、环境污染监测、激光雷达、激光测距、光谱分析、自由空间通信、医疗及材料加工等方面具有很重要的应用价值。因此,掺铥光纤激光器具有极高的研究意义,成为国内外的研究热点。本文从理论和实验两方面对包层泵浦2μm连续波输出掺铥光纤激光器进行了初步研究。 理论上,根据铥离子的能级速率方程组和泵浦光、激光的传输方程,理论分析了泵浦光和激光在增益光纤中的分布情况以及激光输出功率与掺铥光纤长度、腔镜反射率及铥掺杂浓度等参数的关系,并数值计算了激光阈值和斜效率。 实验上,采用中心波长为788nm的半导体激光器...Thulium-doped fiber laser exhibits a broad laser wavelength tuning range(1.7~2.1μm), including the 2μm eye-safe wavelengths and the atmospheric transmission window. It has very important application value in laser remote sensing, environment pollution monitoring, laser radar, laser ranging, spectrum analysis, free space laser communications, medicine and material processing. That's why the Tm-dope...学位:工学硕士院系专业:信息科学与技术学院_物理电子学学号:2312010115299

    The Research and Implementation of Load Scheduling Algorithm and Resource Management Model Based on CG Tree

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    本文研究在CG树模型下的负载调度算法和资源管理模型,以实现分布式集群系统的负载均衡和资源合理利用。通过研究现有的负载调度算法,本文提出了一种基于CG树模型的请求式动态负载调度算法,该调度算法根据集群系统内各个节点所拥有的资源信息和负载情况,结合外界请求的来源和请求内容,动态地选择集群系统内最合适的一个节点来为外界请求服务。该算法能在满足外界请求的同时,有效的实现集群系统的负载均衡。我们提出了一种基于CG树的请求式资源管理模型。该模型能在适当的时候对集群系统中访问次数较多的文件资源进行扩散,使得更多的服务器节点拥有这个资源,以避免系统负载失衡;同时,在适当的时候对外界访问次数很少的资源副本进行删...The Paper studies the load scheduling algorithm and resource management model in CG tree in order to reach load balance and make rational use of resources in distributed server cluster. Through studying existing load scheduling algorithm, we propose a requested dynamic load scheduling algorithm based on the CG tree, which works mainly according to the resource information and load state of nodes i...学位:工学硕士院系专业:信息科学与技术学院计算机科学系_计算机软件与理论学号:2005130231

    Design of Terrestrial Digital TV Set-Top Box

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    2006年8月30日,国家标准委员会正式颁布了《数字电视地面广播传输系统帧结构、信道编码和调制》国家标准。该国家地面数字电视传输标准主要融合了清华大学的多载波方案DMB-T和上海交通大学的单载波方案ADTB-T。随着国家标准的颁布,国内越来越多的城市开始实验移动广播电视技术。截止到2007年底,全国至少有30多个城市实验了移动广播电视技术。本课题就是研究数字电视机顶盒。它能够接收符合国家标准的数字电视信号,并可同时输出数字信号和模拟信号。下面简单介绍本课题的主要研究工作:1、介绍了地面数字电视机顶盒的硬件原理、本系统采用的硬件及其基本特性、软件开发平台和基本构架。2、详细阐述了本系统的红外接收...August 30, 2006, the State Standards Committee officially announced the "digital television terrestrial broadcasting transmission system frame structure, channel coding and modulation." as the national standard. The national standard combines Qinghua University's multi-carrier programme DMB-T and Shanghai Jiaotong University's single-carrier programme ADTB-T. With the publication of national stand...学位:工学硕士院系专业:信息科学与技术学院通信工程系_通信与信息系统学号:2005130239

    新史料与新史学——郑振满教授访谈

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    ○郑老师,您的硕士论文《明清时期闽北乡族地主经济》与博士论文《明清福建家族组织与社会变迁》,都是在傅衣凌教授指导之下完成的。我们很想知道傅先生是怎样引导您的研究方向,而您又是如何研究上述课题的

    Research on Wood Surface Detection Based on Computer Vision

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    基于机器视觉技术对板材表面缺陷检测进行研究,设计了在线检测的硬件系统和软件处理流程,介绍了图像预处理、图像分割和目标提取等处理方法并对缺陷图像进行相应处理。利用C#软件对板材缺陷在线检测进行人机交互界面设计和在线调试及在线检测。实验结果表明,本检测方法可行,误检率低,可很好地应用于木材自动化生产过程的在线检测。This paper presents a study into board surface defect detection based on machine vision technology.On-line detection hardware system and software processing procedure were designed in the study. This paper also described image preprocessing, image segmentation, and object extraction techniques and covered appropriate processing of defect images. C# software was utilized to develop MMI interfaces for on-line board surface defect detection. On- line debugging and on- line detection were carried out. It has been proven by experimentation that this detection approach was feasible and registered a low error detection rate, and may be thus used with advantage in on-line detection during automatic wood production process.福建省科技厅区域重大基金项目(2015H4009);; 莆田市科技计划基金项目(2014G15

    Simulation Design of a Terminal Short-Circuit Type Inter-Digital Band Pass Filter

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    基于悬置线交指滤波器通带内插入损耗比较小,具有很高的选择性和很大的带外衰减,常应用于无线电收、发接收机以及雷达通信系统中。将综合设计法和微波电路仿真软件AdS(AdVAnCEd dESIgn SySTEM)相结合,设计悬置线终端短路式交指带通滤波器。根据交指滤波器的理论得到每个杆的归一化单位长自电容和两相邻杆的归一化单位长互电容,得到滤波器的最初尺寸。并利用AdS软件建模、仿真、优化调整,最后得到该滤波器的几何参数尺寸终值。该设计方法简单,适合工程应用。Inter-digital band-pass filters based on overhanging lines are often used in wireless transceivers and radar communication systems due to their low pass-band inserting attenuation,precise selectivity and high outer-band attenuation.The combination of traditional calculation method and microwave ADS(Advanced Design System) software is used to design a filter of this type.The normalized self-capacitor,mutual capacitor of unit length and the initial value of the geometry parameters of the filter are obtained in accordance with the theory of inter-digital band-pass filter.ADS software is utilized to build model,make simulation and optimizing adjustments.This method is simple and suitable for designing filter in practice.福建省自然科学基金资助项目(2006J0410);福建省科技计划项目(2008H0032

    Simulation design of terminal open-circuit type interdigital band-pass filter

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    基于悬置线交指带通滤波器通带内插入损耗比较小,具有很高的选择性和很大的带外衰减,常应用于无线电收、发接收机以及雷达通信系统中.将综合设计法和微波电路仿真软件AdS相结合,设计悬置线终端开路式交指带通滤波器.根据交指滤波器的理论得到每个杆的归一化单位长自电容和两相邻杆的归一化单位长互电容,得到滤波器的最初尺寸.利用AdS软件建模、仿真、优化调整,最后得到该滤波器的几何参数尺寸终值.该设计方法简单,适合工程应用.The interdigital band-pass filter based on suspended line with low pass-band insertion,precise selective and high out-band attenuation,which is often used in wireless transceiver and radar communication system.In order to design band-pass filter which hangs to place the open-circuit type of the line terminal,the traditional calculate method is combined with the microwave ADS software,the self-capacitor,mutual capacitor and the initial value of the geometry parameter of the interdigital band-pass filter are obtained according to the exact design theory of the interdigital band-pass filter.by building model,simulation,and optimization adjustment,the final value of the geometry parameter for the filter is gotten.The method is simple in designing filter and easily available for engineering applications.福建省自然科学基金资助项目(2006J0410);福建省科技计划项目(2008H0032
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