UML在巡航控制系统中的应用

标准建模语言UML是最广泛使用的可视化面向对象系统的建模方法。在后PC时代,越来越多的领域需要嵌入式系统的支持,尤其是在工业控制领域。本文把基于软件领域的UML作为通用和完善的方法引入到嵌入式系统领域,并以一个嵌入式实时系统"汽车巡航控制系统"为例论述了利用UML的各种标准符号进行从需求分析开始,到系统整体设计的一系列工作。     

Extended Pilot‐Based Coding for Lossless Bit Rate Reduction of MPEG Surround

Pilot‐based coding (PBC), which is used for lossless bit rate reduction of audio coding, has been recently proposed for MPEG Surround. We propose extended PBC for further lossless bit rate reduction of MPEG Surround. Extended PBC selects the number of pilots depending on the parameter band number and the type of spatial parameter. It then encodes the pilots and the relevant difference data. Experiments show that extended PBC is more effective than the original PBC, especially for high bit rate modes, with a negligible complexity increase on the decoder side.     

番茄黄瓜菜汁豆腐加工工艺

以番茄汁、黄瓜汁和大豆为原料研制了色泽美观的天然、营养豆腐,丰富了豆腐的品种,有良好的发展前景。     

饲料混合误差分析方法

简介混合技术发展研究现状,提出了饲料混合机混合误差的概念,给出了混合误差的来源与置信区间,并推导出可用于评估饲料混合均匀度测量误差的计算式。     

谐波提取理论的实践

介绍体效应器件的谐波工作机理和“基波振荡，谐波提取”的理论，根据该理论完成了6mm信号的放大和倍频，成功的设计了从X波段到3mm波段的八倍频组件，大大节约了雷达系统的成本和体积，实现了系统要求的性能。     

一种新型的X.25网络—分组无线数据网络

本文介绍了一种新型的Ｘ．２５网络－分组无线数据网，并介绍了其构成方式及应用范围。     

GSM中的HSCSD技术

介绍了GSMHSCSD技术,及其与GSMphase2数据业务的异同。HSCSD作为从2G系统向3G系统演进的一种过渡方案,能灵活提供高速、多速率数据业务,具有较好的发展前景。     

INVESTIGATION OF PROPERTIES OF INFRARED ABSORPTION OF α-HELIX PROTEIN MOLECULES

The mechanism and properties of infrared absorption of α-helix protein molecules are studied by a theory of bio-energy transport established on the basis of molecular structure. From the vibrational energy-spectra of molecules obtained from this theory we know that the infrared lights with wavelengths of 2 µm ?7 µm can be absorbed by α-helix protein molecules. This is basically consistent with experimental data of infrared absorption of collagen and hemoglobin and bivine serum albumen (BSA) proteins with α-helix structure. From these results we account further for the mechanism and properties of biological effect of infrared lights absorbed by the living systems, i.e., the energy of infrared lights is directly absorbed by the amide-Is in amino acid residues in the protein molecules, which results in vibration of amide-1 and change of conformation of proteins and transport of bio-energy from one place to other along the protein molecular chains in human beings and animals. This is a kind of non-thermally biological effect.     

Evaluation of Thermal Resistance Matrix Method for an Embedded Power Electronic Module

Thermal characterization provides data on the thermal performance of electronic components under given cooling conditions. The most common thermal characterization parameter used to characterize the behavior of electronic components is the thermal resistance. In this work, experiments are conducted to obtain thermal characterization data for different chips in a multichip package. Using this data, it is shown that the assumption of a linear temperature rise with input power is valid within the expected range of operation of the electronic module. Secondly, the applicability of a resistance matrix superposition methodology to the packaging structure of an integrated power electronic module is evaluated. The temperatures and the associated uncertainties involved in using the resistance matrix superposition method are compared to those obtained directly by powering all chips. It is shown that for any arbitrary power losses from the chips, the resistance matrix superposition method can predict the temperatures of a multichip package with reasonable accuracy for temperature rise up to 50degC.     

Microblogging,friendship maintenance,and life satisfaction among university students: The mediatory role of online self-disclosure

Despite a substantial literature suggests that computer-mediated communication impact individuals’ various psychosocial factors, relatively few studies have elucidated the underlying mechanism behind these associations. Building upon self-disclosure theory and previous studies, the principal purpose of this present research is to systematically explore the relationships among microblog utilization, online self-disclosure, friendship maintenance, and perceived life satisfaction. A web-based survey was implemented using a total of 426 university students in Northwestern China. Structural equation modeling reveals that intensity of microblog use is positively associated with these students’ friendship maintenance and life satisfaction. Additionally, online self-disclosure plays the crucial mediatory role in the relationships between microblog use, quality of relationships, and gratification with life. The results imply that as microbloggers disclosure their inner thoughts or emotional states with other users online, they could foster their friendship maintenance and obtain greater life satisfaction. However, contrary to the expectation, students’ friendship maintenance is not discovered to be a significant predictor of the sense of life satisfaction in the online environment. Overall, these obtained outcomes of the empirical work could offer new insights into the deep comprehending of the social psychological process of microblogging among younger generation in the new media context.