电子产品的可靠性设计探讨

通过工程经验总结和理论分析,对电子产品可靠性进行了探讨。给出电子产品可靠性的定义,重点介绍了可靠性预计、电磁兼容设计、抗辐射加固设计、热设计几种电子产品可靠性设计的技术方法。其目的在于提高产品的质量和可靠性。     

雷达电子产品可靠性工程设计应用

对雷达电子产品研制过程中开展可靠性工程设计所应遵循的可靠性设计要求、设计准则及工程设计方法进行深入思考。从而采用有效的可靠性设计技术，达到优化设计的目的，以提高雷达电子产品可靠性。     

IEEE电子产品可靠性及有效性探析

电子产业目前是全球发展最快的行业之一，近年来民用电子产品特别是移动电子产品的普及，导致电子产品的快速更新换代，大大推动了封装工艺、材料以及电子制造装备的发展，使得电子产品的可靠性问题更加突出，因此电子产品可靠性研究已成为学术界和产业界非常关注的问题。     

PCB设计经验浅谈

用计算机进行PCB设计是开发电子产品必经阶段,也是保证电子产品具有可靠性的有力措施.PCB设计的水平直接影响电子产品的性能,本文是作者根据多年的设计经验谈谈PCB设计的有关问题,以供读者借鉴.     

基于PSpice的四阶有源带通滤波器的统计优化设计

针对在实际生产过程中由于元器件参数值的随机分布性而造成电子产品合格率下降的问题，提出了一种基于PSpice的电子电路的统计优化设计方法。并通过四阶有源带通滤波器电路的统计优化设计，验证了该方法可以有效地保证电路设计的可靠性，提高电子产品的合格率．     

电子产品的可靠性试验研究

随时社会的不断发展和科技的不断进步,电子产品已经成为人们生活的必须品,而电子产品的可靠性成为消费者和厂商共同关注的问题,本文就目前国内外电子产品的可靠性发展,电子产品的试验等相关问题做了简单的介绍和探讨。     

电子可靠性工程研究

同类电子产品在市场上的竞争日益激烈,如何使产品具备良好功能的同时提升其可靠性以增强市场竞争力,已成为每个公司迫切需要关注的问题。结合实际工作经验,系统的阐述了如何通过电子可靠性工程,包括可靠性设计、可靠性试验以及可靠性管理等,最终实现产品的高可靠性。     

电子产品在焊接过程中的可靠性问题研究

随着电子制造业不断地发展,对电子产品焊接也愈发关注,以防止对电子产品质量造成不利的影响,开展电子产品焊接过程可靠性问题研究就尤为重要。围绕影响电子产品焊接可靠性的主要因素,对电子产品焊接过程较常出现的质量问题进行细致分析,并从科学选择焊料、优化焊接工艺、加强质量检测等方面入手,提出几点有效保证电子产品焊接可靠性的策略,希望可以为电子产品的可靠焊接提供技术方法指导。     

电子可靠性工程研究

同类电子产品在市场上的竞争日益激烈,如何使产品具备良好功能的同时提升其可靠性以增强市场竞争力,已成为每个公司迫切需要关注的问题.结合实际工作经验,系统的阐述了如何通过电子可靠性工程,包括可靠性设计、可靠性试验以及可靠性管理等,最终实现产品的高可靠性.     

电子产品的贮存可靠性研究

该文研究无线电及电子产品的贮存可靠性问题，针对某典型无线电产品建立仿真分析的数学模型，进行加速寿命试验，以试验数据为基础建立“三大关系”，进而完成了仿真分析，得出电子产品贮存失效的基本规律，确定电子产品的具体可靠贮存年限，并得出加速寿命试验与自然储存的时间对应关系。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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