快衰落信道条件下无线中继系统波束形成方案

随着设备小型化的发展趋势,天线间距较小,信道具有相关性;且假设发射端处于高速移动状态,无法获得完全信道状态信息,只能根据部分信道状态信息设计发射端波束形成方案。针对发射端和接收端配置多天线的固定增益放大转发无线中继系统,以最大化接收端信噪比为准则,设计了基于部分信道状态信息的波束形成方案,推导了系统中断概率和平均误符号率的闭合表达式,通过仿真验证了性能分析的有效性和所设计方案的优越性。在平均误符号率为10-2、相关系数为0.8时,所提方案比反馈信道状态信息的方案节约1.6 dB的信噪比。     

高动态直扩信号快捕设计与FPGA实现

为了解决高动态直扩信号捕获速度与资源消耗的矛盾,分析了部分匹配滤波结合快速傅里叶变换（PMF-FFT）的捕获性能。针对PMF-FFT捕获范围有限且占用硬件资源过多的问题,采用递归折叠匹配滤波器代替常规匹配滤波器的方法大大节省了硬件资源,并行FFT保证了其捕获速度,同时采用扫频方法成倍增加了频偏捕获范围。给出了该方法的FPGA设计结构与实现结果,验证了该方法的有效性。与FFT循环卷积方法相比,在频偏捕获范围一定的前提下,所提方法捕获速度快,占用资源较少,非常适合高动态直扩信号的快速捕获。     

矮牵牛快繁技术研究

以重瓣矮牵牛的不同外植体为试验材料，诱导不定芽，产生再生植株；分别用叶片、茎段、茎尖和花蕾作为外植体进行培养，结果表明茎尖最易诱导产生幼苗，出苗率为90％；继代培养基以MS BA2 NAA0．1最有利于不定芽的产生，用于重瓣矮牵牛的快繁生产。     

食品快速检测技术与方法研究进展

本文简要介绍和总结了国内食品快速检测技术与方法,主要包括食品质量指标、食品添加剂、食品中的微生物、农药残留、兽药残留、转基因食品的测定。     

仓储设备选购及更新决策研究

在分析仓储设备选择原则的基础上,针对仓储设备的选购及更新的经济效益问题,给出了投资回收期法和费用换算法两种方法确定设备选购方案,运用总费用法确定了设备更新方式的选择。     

试论我国央行分支机构从人事管理到人力资源管理的战略转变

人事管理与人力资源管理之间最根本的区别,在于对单位中＂人＂的认识和理解,即单位发展所需要的是一个个作为个体的＂人＂,还是蕴含于人的那些对于工作绩效提升有益的工作能力和综合素质。人事管理与人力资源管理并不是对立与矛盾的关系,两者是相互紧密联系的两个不同层次的管理模式。我国央行分支机构实现从人事管理到人力资源管理的战略转变,关键在于引入新的管理理念,对传统人事管理模式进行改造和提升,从而实现从＂以事为主＂到＂以人为本＂的根本转变。     

The antecedents of in-store hoarding: measurement and application in the fast fashion retail environment

This study raised scholarly inquiry about the construct of in-store hoarding and investigated the antecedents of in-store hoarding in the fast fashion retail environment. As the market becomes dynamic and volatile, more retailers are moving toward fast fashion by constantly delivering new products throughout the season. As a result, a product life span is dramatically reduced, thereby accelerating perishability of fashion items. Moreover, in order to make constant room for new products and minimize markdowns, fast fashion retailers deliberately limit product availability, creating a sense of scarcity on the part of consumers. Based on the literature review and one-to-one interviews, perceived perishability, scarcity and low price were identified as primary drivers of in-store hoarding. Overall, results from a field study supported the proposed model. However, the findings indicated that perceived perishability and scarcity were central to understanding in-store hoarding, whereas low-price perception was least important with a marginally significant effect on in-store hoarding. This study made a significant contribution to the consumer and retailing literature by introducing, defining, and operationalizing new constructs and new measurements, including scales for perceived perishability, perceived scarcity, and in-store hoarding. This study also provided many implications for practitioners in developing and implementing marketing and merchandising management strategies.     

How product representation shapes virtual experiences and re-patronage intentions: the role of mental imagery processing and experiential value

Despite the lack of physical contact, innovative technologies in online stores are able to engender compelling virtual product experiences. The primary objective of this study is to clarify the mechanisms through which these virtual product experiences occur. The study proposes and tests a model in which mental imagery processing and consumers' perceptions of experiential value function as potential mechanisms through which virtual experiences in online stores are established, thereby determining re-patronage intention. The model was tested in an experimental study investigating two versions of a fast fashion online store that varied in terms of product representations: dynamic (i.e., a mix-and-match feature allowing the creation of visual images of apparel combinations) and static (i.e., rigid pictures). A sample of 660 valid cases involving individuals of Generation Y (born in 1977–1994) was obtained. The structural equation modeling technique was used to analyze the proposed research model. The results indicate that the dynamic mix-and-match technology arouses more mental images of physical product interaction than do static pictures. Moreover, mental imagery processing can be considered an important underlying source of online experiential value, which consumers subsequently exploit with repeated visits to the online store. By introducing psychological constructs such as mental imagery and perceived value, this study augments prior research on online product experiences by proposing and validating the underlying mechanisms through which the way of representing products affect consumer responses. Finally, both theoretical and practical contributions of the findings are discussed, as well as directions for further research.     

大比例尺土地变更调查引发的思考

针对当前大比例尺土地变更调查工作强度大、效率低、人工操作复杂的问题,采用个案研究和定性分析的方法,分析了土地变更调查的主要调查内容和影响大比例尺土地变更调查工作效率的关键环节;提出了对大比例尺土地变更调查地区可通过关联业务来控制日常用地管理信息的测绘精度,从而避免由测绘限差引起的影响土地变更调查效率的缝隙和碎面问题;国土资源管理部门应加强对变更软件开发的指导,从而有效降低由于技术与管理脱节而增加的变更工作量。     

基于FFT的突发扩频信号兼容快捕算法

针对传统突发扩频信号捕获算法的缺陷,即无法自适应兼容处理不同同步头时长信号,提出了一种改进的基于FFT的突发扩频信号兼容快速捕获算法。根据不同时长信号的实际应用特性,利用同步头信号尾部对齐的格式特点,采用子矩阵形式存储不同时长信号的码相关结果,通过多支路并行捕获处理,实现突发信号的自适应兼容捕获。同时,通过矩阵的FFT运算同步实现全相干累积来提高信号载噪比,通过时频并行处理提高处理效率,最大限度地优化了弱信号条件的捕获性能。仿真验证表明,算法可以实现不同扩频信号的兼容快速捕获,研究为同步头时长不等的低载噪比信号提供了一种有效的兼容快速捕获方法。