结构陶瓷的高温疲劳强度衰减理论

提出了陶瓷材料疲劳强度衰减理论并由此导出了各种疲劳关系式。建立了疲劳基本方程ｄσ＿ｒ／ｄ＿ｉ＝一Ａσ（ｔ）￣ｎｔ￣（－ｍ），得出了疲劳寿命公式Ｔ＝Ｍ（σ＿０－σ）／Ａσ￣ｎ（静疲劳时Ｍ＝１，连续增载疲劳时Ｍ＝ｎ＋１，循环疲劳时Ｍ＝（ｎ＋１）／（１＋Ｒ＋Ｒ￣２＋……＋Ｒ￣ｎ），逐级加载时，并导出不同疲劳方式下疲劳寿命间的关系。同时，用多种Ｓｉ＿３Ｎ＿４材料在高温中作了论证试验，结果与理论一致。     

Design of optimum signals for the simultaneous estimation of timedelay and Doppler shift

The problem of joint estimation of time delay and Doppler shift is considered from the point of view of the Wigner distribution of the signal. A very efficient method of obtaining the optimum signal with minimum estimation error based on the convexity of the design region is developed. Practical applications, however, require the signal to satisfy other constraints which present complications in acquiring the optimum signal. A design approach based on the method of simulated annealing is suggested to solve for the optimum signal under constraints. The performance of the signals so obtained is evaluated and compared with that of signals obtained by synthesis     

Pattern Effect Removal Technique for Semiconductor-Optical-Amplifier-Based Wavelength Conversion

A technique to overcome pattern dependence in semiconductor-optical-amplifier-based wavelength converters is presented. The technique is based on a careful selection of red- and blue-shifted spectral components having complementary pattern effects in the output spectrum of a wavelength-converted signal. Significant signal quality improvements are reported at a bit rate of 40 Gb/s.     

大花水水电站首部枢纽布置设计

大花水水电站首部枢纽由碾压混凝土拦河大坝、泄洪建筑物和电站进水口组成。大坝采用河床拱坝 左岸重力坝的组合坝型,拱坝最大坝高134.50 m,重力坝最大坝高73 m。泄洪建筑物布置在拱坝坝身,为3个表孔 2个中孔的布置型形式。电站进水口布置于左岸重力坝坝身。首部枢纽布置紧凑,而且充分考虑了坝址区河谷狭窄、地形地貌及、存在的地质缺陷,以及泄洪流量大等工程特点。本文重点介绍首部枢纽的布置设计比选过程。     

大庆油田油气勘探“五五”工程的实践与效果

大庆油田公司确立的油气勘探“五五”工程的核心是立足油气勘探长远发展、统筹老区与新领域勘探,兼顾工程实施与地质研究、系统配套相关技术理论,内容是调整工程和投资结构、完善油气勘探地质理论、发展各项适用技术,目的是促进油气勘探寻求大发现、获得大突破。通过实施“五五”工程,勘探工作运行平稳,勘探成果殷实丰硕,勘探领域层次分明,对油气勘探工作的发展产生了巨大的推动力,确保了大庆探区油气勘探实施的效果。通过对油气勘探“五五”工程实践过程的深入剖析,认为在油气勘探中“思路决定出路、前置加载量是基础、新技术应用是关键”。     

企业开展质量成本研究工作的思考

质量成本是指企业为保证产品质量而支出的一切费用，以及产品质量未达到规定的标准而造成的一切损失的总和。开展质量成本研究工作是企业深化质量管理和成本管理的一条有效途径。     

广东省大型工程建设中天然放射性核素引起的环境问题

本文介绍了广东省境内几个大型基本建设工程项目中天然放射性核素引起的环境问题及有关治理对策，并就今后类似建设项目的辐射环境保护工作提出了建议。     

关于引入劳动力市场价位的思考

引入劳动力市场价位是企业薪酬制度改革的必然趋势。系统研究和分析了劳动力市场价位的基本特征;提出企业在引入劳动力市场价位过程中应该遵循的基本原则。     

TD-SCDMA技术及市场分析

TD-SCDMA技术优势 2000年5月,在土耳其伊斯坦布尔召开的国际电联大会上,TD-SCDMA被国际电联接纳为第三代移动通信系统标准之一,这标志着中国在移动通信技术领域已经进入世界先进行列.     

Catalytic dehydrogenation of ethylbenzene with carbon dioxide: promotional effect of antimony in supported vanadium–antimony oxide catalyst

Alumina-supported vanadium oxide, VO_x/Al₂O₃, and binary vanadium–antimony oxides, VSbO_x/Al₂O₃, have been tested in the ethylbenzene dehydrogenation with carbon dioxide and characterized by S_BET, X-ray diffraction, X-ray photoelectron spectroscopy, hydrogen temperature-programmed reduction and CO₂ pulse methods. VSbO_x/Al₂O₃ exhibited enhanced catalytic activity and especially on-stream stability compared to VO_x/Al₂O₃ catalyst. Incorporation of antimony into VO_x/Al₂O₃ increased dispersion of active VO_x species, enhanced redox properties of the systems and formed a new mixed vanadium–antimony oxide phase in the most catalytically efficient V_0.43Sb_0.57O_x/Al₂O₃ system.