Transceiver cascade system analysis and design via a contribution method

An approach to the design of cascade receiver and transmitter systems for maximum spurious‐free dynamic range (SFDR) is introduced. The contribution method developed here provides a good initial assignment of noise figure, gain, and linearity requirement to individual stages and enables informed assessment of trade‐offs during system design. Application of the approach to the design of a receiver preselector cascade for maximum SFDR is discussed. © 2006 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2006.     

Correction to Dittmar, Halliwell, and Ive (2006).

Reports an error in "Does Barbie make girls want to be thin? The effect of experimental exposure to images of dolls on the body image of 5- to 8-year-old girls" by Helga Dittmar, Emma Halliwell and Suzanne Ive (Developmental Psychology, 2006 Mar, Vol 42[2], 283-292). A substantive error occurs in the Body shape dissatisfaction section on page 287. The sentence describing the calculation of body shape dissatisfaction scores from girls' responses to the Child Figure Rating Scale should instead read as follows: "A body shape dissatisfaction score was computed by subtracting the girl's actual from her ideal body size." (The following abstract of the original article appeared in record 2006-03514-007.) The ubiquitous Barbie doll was examined in the present study as a possible cause for young girls' body dissatisfaction. A total of 162 girls, from age 5 to age 8, were exposed to images of either Barbie dolls, Emme dolls (U.S. size 16), or no dolls (baseline control) and then completed assessments of body image. Girls exposed to Barbie reported lower body esteem and greater desire for a thinner body shape than girls in the other exposure conditions. However, this immediate negative impact of Barbie doll was no longer evident in the oldest girls. These findings imply that, even if dolls cease to function as aspirational role models for older girls, early exposure to dolls epitomizing an unrealistically thin body ideal may damage girls' body image, which would contribute to an increased risk of disordered eating and weight cycling. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

C波段低噪声放大器设计的要点

介绍了用微波工作室软件对C波段低噪声放大器的设计及调试.设计制作的C波段低噪声场效应管放大器,采用全微带匹配网络,利用NEC公司生产的场效应管N32584C,两级级联,用微波工作室软件进行设计、仿真和优化,实现在4.4～5.1GHz范围内增益30dB左右,噪声系数小于0.8dB.用Prote199SE画印制板,该放大器制作在聚四氟乙烯基板上.     

广义智能系统的概念、模型和类谱

研究了“智能系统”的概念、模型与类谱，基本观点认为：“智能”基于“信息”，“智能”寓于“系统”；“系统”基于“物质”，“系统”控于“信息”．系统是南部件组成的有序整体；系统是相对于环境或其他系统而存在的，系统可以和环境或其他系统组成更大的系统．根据上述观点，给出了“广义智能系统”的概念模型与类谱表，不仅可用于现有智能系统的分类、聚类，而且有助于研究开发新的智能系统．     

略论计算机辅助中学生数学空间想象能力培养

从中学数学教学时于空间想象能力的要求和在实际操作过程中的难点出发，结合当前多媒体计算机的特点，主要阐述了多媒体计算机辅助中学空间想象能力培养的五项基本原则：尽可能多地给学生展示各种几何图像和图形；给学生展示几何图形的抽象过程；为学生呈现比较图形；允许学生有比较多的机会参与几何图形操作；逐渐淡化。     

巧妙在Word文档中插入AutoCAD图形

为了绘制图文并茂的文件,常常需要将Word无法绘制而AutoCAD却很容易绘制的复杂图形插入到Word中,本文就此给出了AutoCAD图形插入到Word中的常用方法及图形处理技巧,对一些常见问题作了分析,并给出了解决办法。     

Automated generation of control skeletons for use in animation

Published online: 15 March 2002     

重新认识随时间周期性变化的李沙育图形

电子测量书籍给出的李沙育图形稳定的条件及对不稳定图形的叙述，与实验和理论都不完全符合。本文以用随时间周期性变化的李沙育图形测量微小频率差的公式为例，详细的讨论了这些问题。并得出新的结果。     

An evaluation of criteria used by clinicians to infer pathology from figure drawings.

6 psychologists and 8 nonpsychologists were given a mixture of figure drawings made by 30 normal and 30 psychiatric adolescents and instructed to infer which drawings were by patients and to state the criteria used. All criteria were cross-validated on a new sample (N = 86). Valid criteria of pathology were "bizarre," "distorted," "incomplete," and "transparent." Valid criteria of normality were: "happy expression" and "nothing pathological." Many criteria used by clinicians led to inaccurate inferences. Nonpsychologists discriminated as well as psychologists (65% and 64% accuracy, respectively). An empirically based prediction formula discriminated with 79% accuracy on cross-validation. It is concluded that elimination of invalid criteria can lead to a sharpening of clinical judgment and more accuracy in evaluation of figure drawings. (59 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

平面广告图形设计中的悖谬

广告中悖谬思维并不是对逻辑的背叛,也不是反对思维的既定秩序,而是使受众从相反的方面来认识广告中最为本质的东西,从思维的对立面去寻找新的创意方法,打破固有的思维定式,这也是对广告创作思维逻辑性的发展与完善。