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Lathes are machine tools designed primarily to do turning, facing and boring, Very little turning is done on other types of machine tools, and none can do it with equal facility. Because lathes also can do drilling and reaming, their versatility permits several operations to be done with a single..
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The sound wave is the object mechanical vibrations condition (or energy) dissemination form. The so-called vibration is refers to material the particle the reciprocating motion which carries on nearby its position of equilibrium. For example, drum surface after rap, it on high and low vibrates, t..
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摘要:本文本着为促进工业的发展的初衷探讨了中国软件公园的竞争优势。产业集群深植于当地的制度系统,因此拥有特殊的竞争优势。根据波特的“钻石”模型、SWOT模型的测试结果对中国大连软件园的案例进行了定性的分析。产业集群是包括一系列在指定地理上集聚的公司,它扎根于当地政府、行业和学术的当地制度系统,以此获..
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摘 要:本文探讨了美国大型非金融企业从1964年至2008年股票价格风险的决定小性因素。我们通过相关结构以及简化模型,研究诸如债务总额,债务期限,现金持有量,及股利政策等公司财务特征,我们发现,股票价格风险主要通过经营和资产特点,如企业年龄,规模,有形资产,经营性现金流及其波动的水平来体现。与此相反,隐..
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Abstract : Based on reviewing the historical background, prospecting for the development trend ,analyzing the complicacy and mechanism and summing up some achievements and experiences in scientific research , several new problems and the possible direction of development in material processing..
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I will always remember my first introduction to the power of good product design. I was newly arrived at Apple, still learning the ways of business, when I was visited by a member of Apple's Industrial Design team. He showed me a foam mockup of a proposed product. "Wow," I said, "I want one! What..
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编写 Web 应用程序其轻松程度令人难以置信。它是如此的容易,以至于许多开发人员不用花费多少时间来构筑其应用便能获得非常好的性能。在本文中,我将给出10个编写高性能 Web 应用的技巧。我的评论不仅仅局限与 ASP.NET 应用,因为它们只是 Web 应用的一个子集。本文也不是 Web 应用性能调整的权威指南——这方面的内容可..
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人的眼睛能看到的可见光按波长从长到短排列,依次为红、橙、黄、绿、青、蓝、紫。其中红光的波长范围为0.62~0.76μm;紫光的波长范围为0.38~0.46μm。比紫光波长还短的光叫紫外线,比红光波长还长的光叫红外线。红外线遥控就是利用波长为0.76~1.5μm之间的近红外线来传送控制信号的。常用的红外遥控系统一般分发射和..
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1. One preface The admixture that wind force and solar cells generate electricity to constitute generates electricity the system and is called the breeze/ light to repair the system with each other, all having some common weakness because of the breeze and solar energies, such as the energy d..