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71.
相对于传统的数字滤波器实现方法,符号的2次幂和(SPT)滤波器用移位寄存器替代乘法器,因而资源消耗少、速度快,更加适于专用集成电路(ASIC)设计.介绍了一种适用于宽带码分多址(WCDMA)前向信道中给定基带成形滤波器单位脉冲响应后设计SPT滤波器的方法.相对于传统的理想SPT系数优化方法,此方法更适于给定单位脉冲响应后SPT滤波器的设计,计算复杂度低;仿真结果显示,相对于更加简单的四舍五入方法,此算法在性能上又有可观的增益. 相似文献
72.
基于DMF捕获系统频率选择性信道下捕获性能的分析 总被引:1,自引:0,他引:1
对基于数字匹配滤波器(DMF)捕获系统在频率选择性信道下的捕获性能进行了深入讨论,利用状态转移图推导出单次驻留判决方式时平均捕获时间的表达式,对平均捕获时间与多径分量的关系进行了数字分析。得出的主要结论是:对于多径分量为非衰落信号时,多径分量之间的能量差别越大,系统捕获性能越好,多径分量的能量相等时,系统捕获性能最差,且随着可以分离的多径路数的增加下降;对于多径分量为慢衰落信号时,多径信道的捕获性能好于单径信道(非频率选择性衰落信道),且多径分量之间的能量差别越大,系统捕获性能越差,当多径分量的能量相等时,捕获性能最好,这与非衰落信道的情形相反。因此在频率选择性衰落信道中,采用分集接收可以改善系统的捕获性能。 相似文献
73.
van Baaren Rick B.; Maddux William W.; Chartrand Tanya L.; de Bouter Cris; van Knippenberg Ad 《Canadian Metallurgical Quarterly》2003,84(5):1093
The present studies demonstrated the moderation of self-construal orientation on mimicry. Recent research has indicated that an interdependent self-construal is associated with assimilation of the other to the self whereas an independent self-construal is associated with minimizing the influence of others on the self (H. R. Markus & S. Kitayama, 1991; D. Stapel & W. Koomen, 2001). Therefore, the authors hypothesized that an interdependent self-construal would be associated with more mimicry than an independent self-construal. When self-construal orientations were experimentally primed. as in Studies 1 and 2, independent self-construals produced less nonconscious mimicry than interdependent self-construals. When self-construals were examined as cultural differences with either a chronically dominant independent (Americans) or interdependent (Japanese) construal of the self, these results were replicated. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
74.
Comments on the article "A house divided? The psychology of red and blue America" by D. C. Seyle and M. L. Newman (see record 2006-11202-001). Seyle and Newman concluded that the red and blue metaphor is inaccurate and proposed a purple America strategy to better convey that the majority of people do not align themselves with political extremes. There is interdisciplinary agreement on this. Although not cited by Seyle and Newman, the findings by Professor Fiorina of Stanford University were reported by the APA Monitor on Psychology in its coverage of the 2005 APA State Leadership Conference (Murray Law, 2005). In contrast to their social psychological analysis, Seyle and Newman were incorrect in concluding that "[a]s psychologists, we are not in a position to change either the elements of the American political system that may spur this conflict or even the decisions made by pundits, politicians, and reporters about the terms they choose to use in political discussion" (p. 579). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
75.
Presents a reply by B. Fowers and B. Davidov to Islam's comments (see record 2007-14606-019) regarding their article (see record 2006-11202-002). Islam noted that virtues are often presented as universally valid character strengths, yet formulations of virtues are always embedded in a particular cultural context, a point we took pains to make in our article. We focus our response on Islam's important suggestion that this tension between universal human characteristics and the particulars of cultural context is indissoluble. Whereas he suggested this tension leads to contradiction and paradox, we see it as a fertile dialectic. The virtue of openness to the other is also subject to the same tension of abstract formulation and particular application. Although we formulated this virtue in a very general way, any instantiation of it would be shaped by the particulars of the cultural context and the situation in which it is exercised. We introduced the concept of dialogue because it is constituted not only by differences between individuals or groups but even more fundamentally by the dialectical relationship between those differences in cultural particularities and the universal human capacities for reason, curiosity, and social engagement, among others. Dialogue acknowledges the indissoluble otherness one finds in those culturally different from oneself, and yet real interchange can only occur because participants in dialogue exercise the cognitive flexibility characteristic of human beings and recognize a shared humanity with the other. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
76.
Replies to the comments by R. A. R. Gurung (see record 2003-03405-011) and J. Li (see record 2003-03405-012) regarding comments on the article by R. G. Tweed and D. R. Lehman (2001) which stated that a Confucian-Socratic framework provides a structure for analyzing culture-influenced aspects of academic learning. In this article, Tweed and Lehman argued that these ancient exemplars model approaches to learning continue to differentiate students within a modern Canadian postsecondary context. In this reply, Tweed and Lehman advise caution in how Gurung placed their Confucian-Socratic framework within the context of prior theory on education and epistemological development because these models were developed exclusively in the West. Furthermore, Tweed and Lehman believe that Li's argument misinterpreted their article, and that they should of consistently used the term "personal reform" rather than "behavioral reform" in order to communicate the depth of personal change envisioned by Confucius. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
77.
Anthony Hendrikus Overmars Dario John Toncich 《International Journal of Flexible Manufacturing Systems》1994,6(4):311-331
This paper presents a critical evaluation of existing FMS architectures and the academic and industrial design and development strategies used during their formulation. The paper seeks to address the need for, and value of, existing architectures within the industrial arena. More importantly however, this paper puts forward a new two-tier distributed control architecture for FMS based upon new (real-time) networkable DSP servo control methodologies developed by one of the authors for Softronics in Australia. The ramifications of these methodologies are substantial, not only in terms of FMS control, but in the overall simplification of such systems and the development of flexible fixturing devices over the coming decade. This paper also postulates on how new FMS architectures can be developed from such technologies and details why such architectures could be more appropriate to industry needs than those that are currently in existence. 相似文献
78.
Julia Flanders 《Language Resources and Evaluation》1997,31(4):301-310
This paper discusses the contested role of images in electronic editions, and summarizes some of the chief arguments for their
inclusion. I then argue that, to truly determine the importance of images to the function of electronic editions, we must
understand the contribution the image makes to the form of textual knowledge provided by the edition. I suggest a distinction
between editions which are primarily pedagogical in their aims, those which aim above all at scholarly authority, and those
which attempt to provide textual information as high-quality data which can be analysed and processed. I conclude that the
latter represents the most significant future trend in electronic editing.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
79.
不对称数字用户线(ADSL) 总被引:11,自引:3,他引:8
本文对不对称数字用户线(ADSL)的基本概念,所能提供的宽带业务、技术性能、系统组成作了和说明,并指出利用ADSL,把宽带信息沿普通电话线(铜线)送到千家万户,是数十年时间内过渡到光纤到家(FTTH)的有效传输手段。 相似文献
80.
大曲率表面物体形貌的光学检测方法研究 总被引:13,自引:7,他引:6
本文提出了两种用于曲面形貌检测的傅里叶变换法中的频域低通滤波器,并与常用的窗口法低通滤波器进行了比较,给出了实际测量的结果。这两种频域低通滤波器(高幂次指数滤波器和矩形余弦滤波器)有可方便调整且平直的通带,平直无旁瓣的阻带,较陡的边带将通带与阻带间圆滑过渡连接,从而可尽可能多地保留有用频率成分,很好地滤掉直流和不用的高频分量,且较好地抑制振铃现象,克服一般窗口法设计的低通滤波器中旁瓣的影响。具有使用简单、参数调整方便、应用范围广等特点,尤其是对具有大梯度表面和棱角细节的物体检测更有独到之处,具有广泛的应用前景。 相似文献