期刊文献+
共找到4篇文章
< 1 >
每页显示 20 50 100
基于电阻细分的激光纵向切割长度对片式电阻阻值影响的实验研究 被引量:1
1
作者 王志娟 汤建华 于前洋 《电子器件》 CAS 2004年第3期448-452,共5页
激光在片式电阻上的纵向切割对阻值变化影响较小 ,合理设计其长度可以提高激光调阻精度及保证阻值稳定性。通过电阻细分和实验数据分析得到激光纵向切割长度对阻值影响的定量公式。经实验验证 :该公式的估算偏差不大于 1 % ,能够准确预... 激光在片式电阻上的纵向切割对阻值变化影响较小 ,合理设计其长度可以提高激光调阻精度及保证阻值稳定性。通过电阻细分和实验数据分析得到激光纵向切割长度对阻值影响的定量公式。经实验验证 :该公式的估算偏差不大于 1 % ,能够准确预测经激光纵向切割的电阻阻值的变化趋势和速度 。 展开更多
关键词 激光调阻 纵向切割 电阻细分 估算偏差
下载PDF
激光纵向切割长度对片式电阻阻值的影响 被引量:1
2
作者 王志娟 汤建华 于前洋 《光电子.激光》 EI CAS CSCD 北大核心 2005年第12期1476-1479,共4页
激光调阻中激光束平行于电流方向的纵向切割对片式电阻的阻值变化影响较小,掌握其规律并将其应用于调阻过程中能够为提高激光调阻精度提供控制依据。应用电阻细分方法对片式电阻的阻值分析,定性得到在有效纵向切割长度范围内片式电阻的... 激光调阻中激光束平行于电流方向的纵向切割对片式电阻的阻值变化影响较小,掌握其规律并将其应用于调阻过程中能够为提高激光调阻精度提供控制依据。应用电阻细分方法对片式电阻的阻值分析,定性得到在有效纵向切割长度范围内片式电阻的阻值与相对纵向切割长度成线性关系,阐述了该线性关系的应用,并通过分析0603型1 K电阻的实验数据验证了这种关系。讨论了将其实际应用的可能性。 展开更多
关键词 激光调阻 纵向切割 阻值 阻值变化率 相对纵向切割长度
原文传递
光电跟踪切割机割缝宽度调节螺丝的新作用
3
作者 伍思扬 《机电工程技术》 2001年第6期49-51,共3页
阐述光电跟踪切割机的光电跟踪原理以及光电跟踪切割图或样板的制作,重点分析光电头割缝宽度调节螺丝的作用。
关键词 光电跟踪切割机 光电头 割缝宽度调节螺丝 线跟踪 边跟踪
下载PDF
Impact of population dynamics on Margalla Hills Ecosystem:a community-level case study
4
作者 Aansa Rukya Saleem Fakhra Rashid +2 位作者 Audil Rashid Tariq Mahmood Waqar-un-Nisa 《Chinese Journal of Population,Resources and Environment》 2014年第4期345-353,共9页
Margalla Hills National Park(MHNP) is a declared natural reserve of Pakistan,and Saidpur village is located at its foothills.To sustain livelihood,Saidpur community relies on natural resources and has established an i... Margalla Hills National Park(MHNP) is a declared natural reserve of Pakistan,and Saidpur village is located at its foothills.To sustain livelihood,Saidpur community relies on natural resources and has established an intriguing relationship with the surrounding ecosystem.Human intrusion and related impacts were investigated through self-structured questionnaire from village community to gather information about demography,life practices,natural resource use,and their perception about the environment.Quadrat analysis revealed that the overall plant density was<4 plants/m^2,whereas ordination biplot has indicated significant reduction in plant cover and sparse distribution of species in areas close to human settlement.Survey results show that more than 50%families rely on forest wood as fuel source.Logistic regression has identified education paucity(odds ratio,OR=2.6,95%confidence interval,CI=1.0-6.7),large family size(OR= 5.0,95%CI=1.5-16.6),and fuel type(OR=3.5,95%CI=1.2-9.9)as significant predictors of accelerated forest cutting in MHNP.Male members were mostly illiterate and in favor to promote construction activities which reflects their low concern and casual attitude toward resource conservation.In this study,lack of awareness and peoples' dependency on natural resources emerged as priority challenges,and hence,we suggest provision of alternate fuel sources,better education and sustained income resources as incentives to bring behavioral change.It is pivotal to involve local community before the adoption of any conservation plan as intervention strategy to protect MHNP ecosystem. 展开更多
关键词 Margalla hills forest cutting ordinATION analysis ECOLOGICAL RESTORATION DEMOGRAPHIC pressure Islamabad
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部