GSM无源探测中基于空域宽零陷的DPI抑制新算法

强直达波干扰（DPI）抑制是GSM无源探测系统中的首要问题。根 据系统中DPI与目标回波的特征差异,提出了一种新的宽零陷空域DPI抑制算法。该算法基于 干扰和回波的DOA信息,采用改进的最小约束最小方差准则来实现特定方位上的空域滤波, 能够在对目标回波进行波束赋形的同时有效抑制DPI。仿真结果表明,该算法能获得不低于5 5 dB的抑制增益。     

具有无损吸收功率因数校正变换器的研究

提出了一种无源无损缓冲升压功率因数校正（PFC）电路,与传统的PFC电路相比具有许多的优势。首先,主开关上不引入额外的电压和电流应力;其次,为主开关管的软开关提供了很宽的输入和负载变化范围;第三,限制了主开关管上来自反向恢复输出二极管的导通电流。本文详细分析了无源无损缓冲升压功率因数校正（PFC）电路的工作过程,对没有加无源无损缓冲结构和加了无源无损结构之后的两者电路性能特点进行了比较研究。最后,在理论分析的基础上研制一台250W的实验样机,实验结果表明,本文提出的缓冲结构在设计操作范围内可以有效地减少能量的损耗,提高工作效率。     

利用功率波动的单星无源定位方法

双星或三星卫星干扰源定位体制中定位成功率受制于邻星的选择和星历的精度。针对上述问题,对利用功率波动的单星定位方法进行了研究。探讨了卫星通信链路中天气情况和大气衰减对信号传播的影响,提出了一种单星无源定位方法,分析了通过皮尔森统计方法得到信号功率波动匹配度的可行性,并通过试验证实了该定位方法的有效性。     

完善世贸反倾销协议的几点思考

世贸反倾销协议在过去的几十年中,经历了不断的改进.但一直以来,关于协议中的主要概念--倾销及损害判定标准本身却很少受到质疑.由于倾销及损害的裁定标准非常之宽泛,实施反倾销的条件很容易实现,这使得具有低成本出口优势的中国,一直是现行反倾销措施的最大的受害国.所以,中国应该在世贸组织相关问题的谈判中,提出对倾销及损害判定标准进行合理修改的主张.但对于这一主张的提出,中国不应以一己的利益为出发点,而是要以为中国,为世界带来双赢前景为出发点,来寻求自己摆脱困境的途径.本文正是基于这样的立场,提出对协议中有关倾销及损害这一基本概念的合理性、公正性进行检视的主张,提出了对其进行合理修改的建议.我们期待这一研究会为中国政府在相关问题的谈判中的立场和观点提供理由和依据上的支持.     

电力滤波器的研究现状概述

谐波对电网和其他系统的危害越来越大。解决谐波问题的一种有效方法就是使用滤波装置,无源滤波器因其功率大、成本低等优势在大功率用电系统中得到了广泛的应用;有源电力滤波器(APF)由于有很好的滤波特性及动态特性好等优势一直得到广泛关注,但其容量又限制了其实际应用。将有源电力滤波器与无源电力滤波器相结合,构成混合有源滤波器(AF),取两者之长补有源电力滤波器之短,可以降低谐波补偿系统的成本,达到APF实用的目的。     

What's loyalty?

Loyalty in organizations has proved difficult to predict. One reason is that loyalty is complex and poorly understood. We report two studies that attempt to understand and predict loyalty by focusing on two components of the construct: active-constructive loyalty and passive-constructive loyalty. In the first study, we found that active acts of loyalty were predicted by variables quite different from those that predicted passive loyalty. The second study found that people identified by peers as high-loyalty employees performed many more active sets of loyalty than did those who were identified as low-loyalty employees. We conclude that loyalty consists of both active-constructive and passive-constructive behavior.     

Hirschman's loyalty construct

Of the three key words in Hirschman's (1970) widely cited exit, voice, and loyalty framework, loyalty is the least understood. Some portray it as a third behavioral response to dissatisfaction (after exit and voice). Others see loyalty as an affective moderating variable that influences the choice between exit and voice (and/or the levels of them). Further, of those who interpret loyalty as a moderator, some claim it reduces the incidence and volume of voice, while others argue for the opposite effect. This article compares alternative conceptions of loyalty and identifies conditions under which one or another conception is most appropriate.     

浅谈新闻英语的特点

新闻英语与其他行业用语相比有着不同的语言特征,即词汇属性和时态多变;被动语态使用率高;语法结构复杂,句子冗长;常使用对比和比较;常省略宾语从句引导词"that";常出现多重前置定语。     

Internal and external restructuring over the cycle: a firm-based analysis of gross flows and productivity growth in Portugal

This paper discusses the role played by internal restructuring vis-à-vis external restructuring in industry productivity growth, arguing that the contribution of these two components is expected to be sensitive to the economic cycle. The study describes gross flows (job and output) over a period of one decade, and analyses the productivity differential among continuing, entering and exiting firms in the Portuguese manufacturing sector. The results of the decomposition of industry productivity growth suggest that the share of external restructuring is stronger in recession, while internal restructuring seems to be predominant in expansion. The strong and positive contribution of the net entry effect, in 1991–1994, was not followed by any between and cross effects of equivalent magnitude in the 1994–1997 sub-period. The within effect is, as expected, stronger when output growth is at its peak, but in no case large enough to turn productivity growth procyclical.

被动毫米波探测空中动目标的原理研究

该文系统分析了被动毫米波探测空中目标技术的军事利用价值及国内外研究现状,研究了目标自身的辐射特性以及辐射计的工作原理,提出了探测技术面临的关键技术并设计了一种探测方案原理。分析计算和研究表明,这种探测方案原理是可行的。