首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
将可靠性设计理论与灵敏度分析方法相结合,讨论了车辆常用弹簧的可靠性灵敏度设计问题,提出了可靠性灵敏度设计的计算方法,给出了可靠性灵敏度的变化规律,研究了设计参数的改变对车辆常用弹簧可靠性的影响,为车辆常用弹簧的可靠性设计提供了理论依据。  相似文献   

2.
不完全概率信息下机械零部件的可靠性灵敏度设计   总被引:2,自引:0,他引:2  
应用随机摄动技术和四阶矩技术,将可靠性设计理论与灵敏度分析方法相结合,建立了机械零部件可靠性灵敏度设计模型.提出了基于四阶矩方法的可靠性灵敏度设计的计算方法,讨论了具有不完全概率信息的机械零部件的可靠性灵敏度设计问题;探讨了机械零部件的可靠性随设计参数改变的数学评价方法,给出了可靠性灵敏度的变化规律;研究了设计参数的改变对机械零部件的可靠性的影响,并且获得了理想的数值设计结果.为机械零部件的可靠性设计提供了理论依据.  相似文献   

3.
螺旋管簧的可靠性鲁棒设计   总被引:1,自引:0,他引:1  
在可靠性优化设计理论与可靠性灵敏度分析方法的基础上,讨论了螺旋管簧的可靠性鲁棒设计问题,提出了可靠性鲁棒设计的数值计算方法,把可靠性灵敏度溶入可靠性优化设计模型之中,将可靠性鲁棒设计归结为满足可靠性要求的多目标优化问题。  相似文献   

4.
薄壁压力容器的可靠性分析   总被引:1,自引:0,他引:1  
利用可靠性理论对薄壁压力容器进行了可靠性分析与设计。给出了薄壁压力容器进行可靠性分析所必备理论基础。作为算例,对某间歇蒸馏装置塔底再沸器的筒体厚度,进行了可靠性设计。与传统常规设计分析比较,结果表明:从设计理念上,薄壁压力容器的可靠性设计优于传统常规设计。  相似文献   

5.
本文阐述了可靠性设计在压力容器设计中的重要性。介绍了常规设计与可靠性设计的区别、可靠性设计的概率统计基础、设计参量的统计处理以及压力容器可靠性设计的内容和步骤。用算例邦助读者掌握计算方法,并由实验加以验证。  相似文献   

6.
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。  相似文献   

7.
工程机械零件的可靠性优化设计   总被引:2,自引:0,他引:2  
通过对机械产品可靠性的评价,分析了传统设计方法与可靠性设计方法在设计思想、设计原理上的区别.运用可靠性理论与最优化设计技术,提出了机械零部件的可靠性优化设计方法.在满足可靠度约束及结构几何约束的条件下,以体积最小作为优化目标函数进行可靠性优化设计,得到了比常规设计更为合理的设计结果.  相似文献   

8.
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。  相似文献   

9.
机械产品的可靠性设计与试验   总被引:1,自引:0,他引:1  
归纳了机械产品可靠性的特点和可靠性设计应遵循的原则,以一个例子比较和分析了机械零件的传统设计与可靠性设计的特点,介绍了机械产品的可靠性试验和分析的方法.  相似文献   

10.
利用可靠性安全系数进行机械可靠性设计 ,对实现机械设计方法由常规设计向可靠性设计过渡具有一定的现实意义 .根据可靠度、强度及应力变差系数对可靠性安全系数的影响 .对三种常用的可靠性安全系数的相对误差进行了对比分析 .按照设计结果既要安全可靠 ,又要与实际情况相符的原则 ,给出了它们各自适用的条件 ,为机械可靠性设计中正确选用可靠性安全系数提供了依据 .实例的计算结果表明文中所给结论具有实用价值 .  相似文献   

11.
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.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
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.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
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。  相似文献   

16.
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.  相似文献   

17.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

18.
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-  相似文献   

19.
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-  相似文献   

20.
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  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号