零电夺控制的无触点开关

零电压控制的无触点开关，又名固态开关或固态继电器，它是一种性能优良，很有发展前任的新器件。本文介绍了新型固态开关的原理和性能指标以及在交流电子开关中的应用。     

500kHz—1.3MHz零电压准谐振DC／DC变换器

本文以升压(boost)变换器为例,简单地介绍了零电压准谐振DC/DC变换器的工作原理及设计方法,并给出500kHz—1.3MHz升压和回扫(flyback)零电压准谐振变换器的实验结果。     

单片集成电路实现大功率开关稳压控制

脉总宽度调制开关稳压集成电路TL494应用在大功率开关稳压器中，可以实现斩波和变换器等多种型式的调压及稳压电路的简化设计，本文介绍了这两种应用。     

MIMO系统的波束成形技术与开关算法结合的性能分析

提出了一种在多用户情况下多输入多输出系统用开关算法结合波束成形技术的方法 。对3种波束成形技术的方案研究表明,波束成形的处理过程对开关算法的判决准则有重要 影响。从仿真结果可以看到,空时分组码的自适应波束成形算法与开关算法结合时在误码率 为10 -2时,信噪比比迫零算法结合和奇异值分解算法结合时分别提高7 dB和8 dB 左 右。     

零电压控制的无触点开关

零电压控制的无触点开关，又名固态开关或固态继电器．它是一种性能优良、很有发展前途的新器件。本文介绍了新型固态开关的原理和性能指标以及在交流电子开关中的应用。     

脉冲宽度调制直流变换器的应用

本文详细介绍了Ｍａｘｉｍ公司脉冲宽度调制直流变换器ＭＡＸ７２４／７２６的原理和应用，包括降压变换器、升压变换器、逆向变换器。提供了典型应用电路图、设计公式以及关键事项。     

用超小型铁芯控制的DC—DC变换器

一、概述 DC—DC变换器的体积和重量主要取决于变压器,平滑滤波器的大小。为了实现变换器的小型化,必须提高开关频率。高频变换器设计的中心问题是加快开关速度,减少开关损耗。这可从两方面着手;第一,选择快速开关器件,例如功率场效应管等;第二,改善功率开关的激励方法。后者也可使双极性晶体管工作在很高的频率上。为了将频率提高到兆赫量级,必须减小可饱和铁芯的饱和磁通,使用在高频领域也有良好非线性特性的磁芯。本文介绍用无磁致伸缩的钻基非晶材料作可饱和铁芯,双极性晶体管作开关元件,开关频率在兆赫量级小型变换器及其实验结果。     

厂商动态

讯宝科技推出PartnerSelect独立软件开发商计划；双汇软件力助连锁店开遍“万村千乡”；2004零售单店百强发布，长益用户率继续高居榜首。     

新材料项目展示

NO.1/磁感应接近开关 项目简介 工矿企业自动控制系统中大量使用的行程开关、限位开关、保护开关、检测开关等是对生产车间中机器旋转（或直线）运动零部件或产品等进行行程、限位、保护、检测和位置自动控制的重要开关。     

透过零供矛盾形式变化谈零供合作

本文旨在通过对现实零售商供应商矛盾的各种表现形式及其背后动因分析,使各方能够对现实零供关系有个正确的认识,能够理性看待零供冲突和零供矛盾,从而为政府、供应商和零售商等各方从自身出发寻找解决零供矛盾的办法提供借鉴。     

锁相技术在高频开关电源中的应用

本文介绍了锁相技术在电流控制两态调制技术的高频开关电源中的应用。开关电源整个控制环路相当于一个锁相环,这个环路不仅有锁相作用,而且还有调压作用。实验表明,这种高频开关电源有优良的性能。     

开关电源的最新动向

本文从开关电源电路技术、组装技术出发,介绍了日本目前开关电源的发展历程、现状以及今后发展动向。指出开关电源迅速向低成本、小型化、薄型化和高效率方向发展,对于随之而产生的高次谐波的影响及其对策作了较详细介绍。     

Contrasting the Drivers of Switching Intent and Switching Behavior in Contractual Service Settings

We examine consumer switching decisions in contractual service settings and contrast the drivers of actual switching with those of switching intent. We surveyed a panel of subscribers to all cell phone service providers in a market and recorded key marketing mix data. At four months intervals, we asked panel members about their switching intentions and then subsequently observed actual switching behavior. Consistent with construal level theory, our findings show that switching intent is explained by only a handful of desirability- or outcome-related variables (i.e., overall satisfaction, performance perceptions of important attributes, and monetary switching costs). In contrast, the results show that many more variable categories contributed to explain actual switching behavior. These findings confirm that switching intent is driven by a qualitatively different set of variables than switching behavior. Implications for theory, research and practice are discussed.     

Why do online grocery shoppers switch? An empirical investigation of drivers of switching in online grocery

The article sets out to develop a deeper understanding of the drivers of switching behavior in an online grocery context, which is becoming a key area of focus for grocery retailers. Applying the push, pull, and mooring framework (PPM) popularly used in migration and switching literature, we empirically assessed factors that might contribute to online grocery switching. The results highlight that retailer-related push factors (customer service, issues with delivered products, technical issues, and high price perception) and competitor-related pull factors (WOM and alternative attraction) have significant direct effects on switching. Furthermore, the results also show that consumer-related mooring factors (switching cost and prior switching behavior) significantly moderate switching. The findings provide valuable insights to retailers on the drivers of switching behavior in online grocery retailing, which can be used to develop strategies to reduce consumer switching and hence increase consumer retention.     

行波管发射机高压开关电源变压器的优化设计

对高压开关电源变压器的设计进行了改进，降低了变压器的损耗和漏感，解决了变压器绝缘耐压问题，并有效减小了变压器与外界的热阻，可广泛用于行波管发射机高压开关电源。     

应用在固态发射机上的高性能特种开关电源

某型号固态发射机，要求电源提供20kW的功率，同时满足现代固态发射机对电源的高性能的要求，为此，设计运用5台40V／100A的开关电源模块以并联均流的工作方式为发射机提供电源。本文详细介绍了40V／100A开关电源模块的主要技术指标、系统组成和工作原理，给出了主要元件的设计方法，概述了选择低温器件的思路，最后给出了样机的实验结果。实验结果表明，所提出的电路方案是切实可行的。     

A cross-cultural study of switching barriers and propensity to stay with service providers

This study examines the important and often underestimated role that switching barriers play in the propensity to stay with service providers. Three service types (with different structural characteristics) were studied across two diverse cultures—Australia (Western, individualistic culture) and Thailand (Eastern, collectivist culture). Six potential switching barriers are examined: search costs; loss of social bonds; setup costs; functional risk; attractiveness of alternatives; and loss of special treatment benefits. The results from a series of multiple regression analyses show switching costs capture a substantial amount of the explained variance in the dependent variable, propensity to stay with a focal service provider. Furthermore we demonstrate using interaction terms that these switching costs appear to be universal across west-east cultures. However, significant variations were found across industries. Next, using a hierarchical regression procedure, we add a satisfaction variable into each model. The incremental gain in R² is significant in each industry. Nonetheless the significant impact of switching barriers gives rise to the identification of a new type of service loyalty, which we term “captive loyalty.”     

一种快速离化波开关及其在高压脉冲源中的应用

讨论了一种先进的基于快速离化波组件漂移阶跃恢复二极管 (DSRD)的开关特性、工作 原理及其在高压纳秒脉冲源中的应用。提出一种新方法解决了传统高压纳秒脉冲源设计难 以突破的高功率、高重复频率工作问题,实现了高压纳秒源的全固态、高重频、高压、高可 靠、长寿命工作。     

The Impact of Service Characteristics on the Switching Costs–Customer Loyalty Link

This research investigates the interrelationship between service characteristics and switching costs and makes two contributions to the service retailing literature: (1) As a means of better understanding the effectiveness of switching costs, the study suggests a two-dimensional typology of switching costs, including internal and external switching costs and (2) it reveals that the effect of these switching costs on customer loyalty is contingent upon four service characteristics (the IHIP characteristics of service). We carried out a meta-analytic review of the literature on the switching costs–customer loyalty link and created a hierarchical linear model using a sample of 1,694 customers from 51 service industries. Results reveal that external switching costs have a stronger average effect on customer loyalty than do internal switching costs. Moreover, we find that IHIP characteristics moderate the links between switching costs and customer loyalty. Thus, the link between external switching costs and customer loyalty is weaker in industries higher in the four service characteristics (as compared to industries lower in these characteristics), while the opposite moderating effect of service characteristics for the internal switching costs–loyalty link is noted.