结构工程和结构反应修正研究：中心法
George C. Lee1
摘要
本文从一个系统表现的角度简要介绍了多学科地震工程研究中心(MCEER)里的结构工程研究活动。多学科地震工程研究中心是由国家科学基金会成立的用来对一些无法用单个研究者的方法完成的地震工程研究进行系统集成研究。
通过使用“中心方法”，结构工程研究成为可以贡献给一个系统所需的性能水平的组成部分。在这种系统下，结构工程项目包括地震反应修正技术的例子都可以罗列出来。
关键词：结构工程研究；中心法
1.0简介-多学科地震工程研究中心研究程序
多学科地震工程研究中心的研究目标是双重的：对那些社会希望在地震后力技能使用的如医院和电力水利线的重要设施系统，发展地震评估和重建策略，用以增加地震的弹性范围；用发展改善的紧急管理能力来确保震后有效的反映和恢复，以使进一步加强地震弹性范围。
这些研究目的的重要性由最近的一个国家科学基金赞助的研究项目予以支持。在1999年，一个调查在加利福尼亚州Alameda县举行，那个地方经受了很多Loma Prieta 地震的影响。给受访者提供了一个有20种结构和系统类型的清单，比如学校，办公楼，公寓，高速公路，水利系统，传播系统等，要求受访者辨识出五个最重要的必须在震中
Samuel P. Capen 工学教授兼主任，多学科地震研究中心，纽约州立大学水牛城分校，水牛城，纽约14261 美国，gclee@https://www.doczj.com/doc/b76892866.html,。和震后维持使用功能的结构或系统。三个最常给出的答案是：水利管道和设施（76%的受访者提到）；医院（76%）；电力线和设施（73%）。重要性仅次于上述三个的是公共安全建筑的功能性（48%）。这四种被Alameda县受访者认为是最重要的应该在维持功能的四种建筑系统和多学科地震工程研究中心用“中心法”对三个联合项目分析的方面所认定的需要加强研究的方向完全重合。
多学科地震工程研究中心的重要研究区域可归纳如表１。
2.0 地震评估和医院的修缮
多学科地震工程研究中心研究的目标是为了重建医院医师达到或超过这些设施所需要的高性能水平，来辨认、探究和发展先进技术。这些技术的最初花费可能会高，但是建立在持续研究努力的基础上的增加的实施成本会减少未来的花费，以使总花费比传统的维修费用更低。
为了合理解释在建筑类型，地震环境和美国东西部的意识上的差异，纽约州立健康部（NYSDOH）和加州州立健康规划发展办公室（COSHPD）建立了紧密的联系。加州在已经实施了法律，规定维护建筑设施的健康状况是必须的，在2001年１月之前以使其能够经受住地震的破坏，在2008年之前升级这些建筑以确保生命安全，2030年之前保持建筑系统的震后使用功能。先进的技术已经作为潜在的实现这些紧急的震后修复工作的唯一手段被加以考虑。在加州州立健康规划发展办公室和多学科地震工程研究中心之间的合作关系是相当理想的来实现预定的协同目标。而且，纽约州立健康部的重要成员的参与提供了相似的优点，尽管这些
较少地震意识的州的减震认识在法律压力的缺失下，将会要求另外的努力来正视在社区里合理分配医院的地震修复工作的资源。
多学科地震工程研究中心的医院研究项目可以被分成以下任务。
2.1 技术组合：结构方面
技术组合包含了一个低风险，中等风险和高风险技术的组合。低风险的技术被定义为那些接近完成并且更容易被接受的技术。中等风险技术是那些处于中期范围接近于完成的，有可能容易被接受的技术。高风险技术是那些处于长期接近于完成的潜伏期，并且有可能被接受的技术。
这个任务目前投资于下列技术：被动控制技术——阻尼器和地基隔离系统（低风险）；金属被动消能方法（低风险）；采用新型复合材料的被动消能方法（中等风险）；混合系统（高风险）。这个任务主要集中在被动消能的概念（目前最有前景的），这些技术可以被分为两种不同的方法。具体的手工制造仪器的使用和填充材料的使用。各种方法中，需要考虑处于不同风险级别的技术。
此时，一些技术的存在提出了一些迫在眉睫的问题，确实可能在新材料中发现最佳的解决方案并促使技术的不断出现。因此，多学科地震工程研究中心通常建立工作室来观察新的和即将出现的材料，并促使新技术可以在地震修复工作中应用。这就确定了结构技术组合任务的动态本质。
2.2 技术组合：非结构评价和修复
非结构单位的地震表现在医院中是最重要的问题。多学科地震工程研究中心在地震表现和非结构单位方面的研究集中在确保医院的重要设施在强烈的结构反应后能够维持使用性能。
因此研究必须用来确定引导向那些不可取的性能级别的条件。通向这个复杂问题的解决方法的道路上有很多障碍。首先，影响地震表现的关键参数对于不同种类的失败和需要考虑的非结构系统并不是众所周知的，无论这些是峰值或是相对的最低值加速度，速度，位移，能量或是其他。这就要求在脆弱型曲线的校准和敏感性上开展基础的研究工作，还有建立各种系统性能的实验性测试，考虑了振动设备，滑动设备，轻和重的管道系统设备，大型的贮水池和水库，还有一些其他的特殊重要单位，像是起重机。其次，用来有效修复系统的最有前景的先进技术一定会被识别出而且它们的有效性一定会被分析性和实验性的建立起来。第三，一定要理解和优化结构和非结构修复之间的复杂互动。确实，一些结构修复可能会减少或消除很多非结构修复的必要性，而且是否应该用昂贵的技术来控制结构行为或是投资来完全修复费结构设施是个无法回答的问题。考虑到由于地震修复在国内不同的地震地区可用资源和目标变化非常大，这是尤其重要的，可以接受的地震表现水平相应产生变化。在地震和非地震中权衡的最好决策就是同样受制约这些限制。这也需要对于结构和非结构单位的脆弱性分析建立复杂的联系，很大程度上还基于这些分析的可靠性。
2.3 脆弱性分析的发展
震后医院的所有功能的实现是一个要求考虑应用非常规分析工具的一个严格表现。而且，工程师一定要能在结构和非结构的表现方面，通过主要决策人的格式化管理，制定他自己的建议。经验表明，概率性的方法最适合这个目的，脆弱型曲线可以提供问题所需要的可取形式的框架。这个分析平台还使整合地震的不确定性成为了可能，而且可以用一个用来做成本效益分析的合适形式来提供工程数据。这个研究任务里的重要挑战是：第一，脆弱性内在决定于实践的和准确的分析工具的可用性。研究需要用来建立在计算复杂性的收益中是否以及如何能够加强脆弱曲线的可靠性。第二，作为峰值地面
加速度的功能，脆弱曲线的代表是不准确的，一定要观察到放大的可供捕捉的地面活动的代表性的其他测量方法。为了找到脆弱曲线的准确简单的定义，一定要进行基本的研究包含随机过程的样本性质，伴随着为了实践实施的特征地面运动强度测量的简单方法。第三，对应于不确定系统和输入参数的不同地震表现指标的成分，也被叫做敏感因子，可以被用于辨认一个系统的关键部分，关键部分就是指那些影响系统中最重要的总体地震表现。对现有结构发展合理的修缮措施，重要组成部分的特征是很有用的。然而，现有电脑语言没有提供有关影响因子的任何信息。
2.4 促进技术：结构评估和修复
限制在多学科地震工程研究中心医院项目的范围内的促进技术和方法一定要在有建筑和工程专业团体的建筑修复中发展来实现先进的技术。关于系统的表现是系统整合方法的核心（拥有附加设备和材料单位的结构），以使成本效益策略可以由设计师针对某特定的结构和规定的地震风险。研究范围包括一些很基本的结构动态反应，一方面，这些反应可能只能通过包括非线性影响的多自由度模型来研究，另一方面还有一些很实际的问题，像是简单的设计指导和步骤。在这之间，一个主要的挑战是对用户友好的电脑程序作为工程师实现成本效益修缮策略的发展。
在美国东部发现的医院通长有钢结构的框架系统，久远一点的医院采用灵活的半刚性连接，新近的医院使用更多的是有刚节点的传统钢框架。当位于密度大的城镇中心时，很多20层高的中层建筑在密集的城镇中心变得很普遍。因此，这些建筑通常有一个引起较小地震力的较长的周期，但是在地震中尤其会有大的位移，也就可能因此遭受结构和非结构上的损害，而且在某些情况下会冒着由于整体失稳而倒塌的危险。这种后来的损害状态尤其难易度量，而且可能要求特殊关注。在全国发现的一些典型的低层的医院建筑也依靠柔性框架来抵抗地震，框架赋予的更大的建筑柔性有相当大的吸引力。事实上，在很多事例中，原本矗立在在久远一点的医院的钢框架里的砌体分割填充物通常随着时间的流逝和很多医院认识到空间的利用和经受各种重建后已经被去除了。对于地震修复的先进技术，有柔性结构系统的医院这种类型的建筑因此需要并且首先被观察。滞后的能量耗散牺牲单元和被动和半主动的阻尼技术都在向着那个目标努力。当阻尼在美国西部变得越来越流行，他们的造价可能会成为在对于中级地震反应不强烈的地区推广实践的障碍。特殊的滞后结构单位可能会更容易接受，但研究要求确定哪种方法能够引导向让人满意的地震表现。因此，两种策略都必须坚守，（a）阻尼技术和影响阻尼器的表现的方法（像是剪刀插孔阻尼器）一定要被观察，（b）先进的复合或是水泥质的材料一定会被认为是有利于修正建筑响应的潜在技术。用来控制大位移和潜在失稳影响并且不减少周期（像是阻止大的最小加速度）的技术是可取的。
2.5 岩土技术组合：液化土的评估和修整
至此，一个重要的问题出现了，很多医院都建在地震后容易液化的土壤上。虽然在空地上加固这种液化土相对较容易，但现在不存在那么简单的修复方法，以使地质修复对建筑物达到最小以至没有扰动。当试图模拟液化土中的桩基础模型时，由于现存的分析模型的不足，问题进一步复杂了。医院项目的地质研究把目标放在先进技术的试验观察上，用来填补知识的空缺，集中精力发展与地震修复工作相关的分析工具。
2.6 决策模型：社会和经济的激励和阻碍
除非最终实施了，最好的地震修复技术也是没用的。虽然一些医院的拥有者和管理者在司法上被暴露在最严重的地震风险中会准备采取修复措施并采用这些新的先进技术，但其他人要求先回答一些重要的非技术性的问题。预算限制了资源的分配，很不好的
影响了地震修复的努力，尤其在那些即使有大地震风险但地震意识最低的地区。因此，为了保证广泛的和有效的实施，要求社会研究清楚的识别阻碍实施的本质，确定什么样的实施激励措施是可行的，量化由于各种政策措施产生的微观社会利益。这就要求研究直接从医院拥有者/管理者和公众方面直接收集有代表性的信息，建立现有的观点和期望，确定各种措施如何积极的修正这些位置。考虑到地震修复需要资金的展现，决策者很难在没有确保清晰利益前景的情况下正视这些花费。为了克服这个经常引起现今深刻变化的问题，可靠的成本效益分析，具体为认识到医院的特点而量身定做的，一定要发展起来。这种决策工具使观察各种地震修复方法的相对收益成为了可能，并用来确定最好的方法。
3.0 医院的模型
正如早先指出的，多学科地震工程研究中心医院项目在最初就被分成了两个不同的方面。对于更加一般的情况（以加州医院为代表），大部分的精力都被用在工程活动中，对于物理单位和系统来建立脆弱性信息，识别出需要地震修复的结构、非结构单位，和设备等中的重要问题区域。对于特殊情况（以纽约医院为代表），我们集中精力建立这样一个决策模型，它可以提供震后医院的功能是否丢失对于一个社区的影响，由于医院所需要的不同功能所对应的不同破坏等级。一旦确定了一个地震修复方案，过程就会和加州医院的方案相融合。基于那一点，当有很多医院需要不同可能性的地震修复选择成本效益分析时，我们会考虑其对于社区的影响。
以上可由图2加以说明，显示了现在多学科地震工程研究中心的医院任务。
为了说明“中心方法”在地震工程研究中的应用，医院性能表现分析和图2的单位评估都会被检验的。为了描述医院的医疗服务功能，我们加深了“病人流”模型的概念，如图3所示。
如果医院的服务功能被认为是一个过程，这个病人流中的关键单元就是面多病人如何接受医疗过程中心模块。这些服务由人力资源和材料资源所支持。既然结构工程关心的是评估结构的或是非结构的修复，重点就可以放在材料资源上，典型的包括电力系统，水利系统，细心系统，医疗系统，交通系统，暖通空调和其他。基于医院的代表作用（肿瘤中心，一般医院，特殊医疗看护等），中心会包括不同的服务单位。
4.0 结构反应修正研究
在图3中的病人流模型中，我们可以分开考虑需要递送以来哦服务的物理系统的重要性。一个简单的医院物理系统如图4所示。
虽然图4中的物理系统模型展示了各种结构和非结构的设施设备系统当他们影响到医疗服务的功能和能力的时候的错综复杂的关系。它也提供了一种多学科地震工程研究中心医院项目的地震工程研究的系统观点。
例如，大部分的结构反应修正技术都为基础和结构系统，还有很多非结构单位所用。最有挑战性的研究区域就是就够系统反应减少和非结构单位修复之间的权衡。为了时间这样一个优化研究，我们必须拥有这些相关信息，反应修正技术和他们的设计方法，以及图4中列出的所有跟物理单位相关的脆弱性信息。因此，需要展开大量的结构工程研究活动，包括分析性和实验性的。这就要求跨学科团队的向着医院服务的共同目标努力。可以很好的通过紧密协调的“中心法”来实现。
虽然结构工程和结构控制单位在他们自身本质上可能是基础的和应用工程研究的，但它是可以为易受震害社区提供成本效益和有用结果的社会科学单位的合理的整合和协调努力。
5.0 总结
多学科地震工程研究中心的研究项目是根据减少城镇中心易受地震的使用者的观点来构思和设计的。这种使用者的需求变成一些性能需求，要求各种重要的设施在震中和震后可以维持使用功能，像是紧急医疗服务。决定修复和各种成本效益的修复方法，尤其是采用新的即将出现的技术，需要一个系统整合的方法，用“中心法”比“单个观察者的方法”更有效。在本篇论文中，通过描述多学科地震工程研究中心的结构工程研究和作为医院项目单位的反应修正技术，简要阐述了这种中心法。
6.0 鸣谢
本文中所汇报的给与多学科地震工程研究中心的资金由国家科学基金（EEC-9701471）和纽约州(C-000591)提供。本文中所提到的，在各个研究单位工作的结构工程研究者包括：A. Aref, S. Billington, M. Bruneau, I. Buckle, M. Constantinou, G. Dargush, M. Ettouney, M. Grigoriu, G. Lee, M. Maragakis, A. Reinhorn, M. Shinozuka, M.P. Singh, T. Soong 和A. Whittaker. 另外，下列社会科学研究者也参与了医院的项目：K. Tierney, J. Nigg, E. Sternberg, Y. Okayama, W. Petak 和H. Kunreuther.
7.0 参考文献
1. 多学科地震工程研究中心网站https://www.doczj.com/doc/b76892866.html,
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3. Lee, G.C. and Tong, M. “美国东部医院的修缮方法”，第四届韩国地震工程中心国际研讨会会议记录，2001
中等分辨率制备分离的 快速色谱技术 W. Clark Still,* Michael K a h n , and Abhijit Mitra Departm(7nt o/ Chemistry, Columbia Uniuersity,1Veu York, Neu; York 10027 ReceiLied January 26, 1978 我们希望找到一种简单的吸附色谱技术用于有机化合物的常规净化。这种技术是适于传统的有机物大规模制备分离，该技术需使用长柱色谱法。尽管这种技术得到的效果非常好，但是其需要消耗大量的时间，并且由于频带拖尾经常出现低复原率。当分离的样本剂量大于1或者2g时，这些问题显得更加突出。近年来，几种制备系统已经进行了改进，能将分离时间减少到1-3h，并允许各成分的分辨率ΔR f≥（使用薄层色谱分析进行分析）。在这些方法中，在我们的实验室中，媒介压力色谱法1和短柱色谱法2是最成功的。最近，我们发现一种可以将分离速度大幅度提升的技术，可用于反应产物的常规提纯，我们将这种技术称为急骤色谱法。虽然这种技术的分辨率只是中等（ΔR f≥），而且构建这个系统花费非常低，并且能在10-15min内分离重量在的样本。4 急骤色谱法是以空气压力驱动的混合介质压力以及短柱色谱法为基础，专门针对快速分离，介质压力以及短柱色谱已经进行了优化。优化实验是在一组标准条件5下进行的，优化实验使用苯甲醇作为样本，放在一个20mm*5in.的硅胶柱60内，使用Tracor 970紫外检测器监测圆柱的输出。分辨率通过持续时间（r）和峰宽（w,w/2）的比率进行测定的（Figure 1），结果如图2-4所示，图2-4分别放映分辨率随着硅胶颗粒大小、洗脱液流速和样本大小的变化。
变频器外文翻译文献 (文档含中英文对照即英文原文和中文翻译)
外文: Converter reference design (1)Converter Selection: Selection to determine the frequency converter when the following points: 1) The purpose of a variable frequency; constant pressure to control or constant current control. 2) the load converter types such as leaves or pump volume pumps, with special attention to load the performance curve, the performance curve of the decision of the ways and means. 3) the frequency converter and load matching Voltage match: a rated voltage converter with a rated voltage line with the load. Current matches: ordinary pump, the rated current inverter and motor rated current match. For special load such as deep-water pumps, and so on need to refer to the electrical performance parameters to determine the most current inverter current and Guozainengli. Torque match: in this case constant torque load or slow down when the device may have occurred. 4) the use of high-speed motor drive inverter, because of the high-speed motor, anti-small, high harmonics lead to increased output current value increases. So for high-speed motor inverter Selection, its capacity to be slightly larger than the ordinary motor selection. 5) If the frequency converter to a long cable run, this time to take measures to curb the long cable to the impact of capacitive coupling, inadequate efforts to avoid converter, so in this case, the drive to enlarge the capacity of a file or the converter Output installed output reactor. 6) For the application of some special occasions, such as high temperatures, high altitude, at this time would cause the down converter capacity, the drive to enlarge the capacity of a block.
forced concrete structure reinforced with an overviewRein Since the reform and opening up, with the national economy's rapid and sustained development of a reinforced concrete structure built, reinforced with the development of technology has been great. Therefore, to promote the use of advanced technology reinforced connecting to improve project quality and speed up the pace of construction, improve labor productivity, reduce costs, and is of great significance. Reinforced steel bars connecting technologies can be divided into two broad categories linking welding machinery and steel. There are six types of welding steel welding methods, and some apply to the prefabricated plant, and some apply to the construction site, some of both apply. There are three types of machinery commonly used reinforcement linking method primarily applicable to the construction site. Ways has its own characteristics and different application, and in the continuous development and improvement. In actual production, should be based on specific conditions of work, working environment and technical requirements, the choice of suitable methods to achieve the best overall efficiency. 1、steel mechanical link 1.1 radial squeeze link Will be a steel sleeve in two sets to the highly-reinforced Department with superhigh pressure hydraulic equipment (squeeze tongs) along steel sleeve radial squeeze steel casing, in squeezing out tongs squeeze pressure role of a steel sleeve plasticity deformation closely integrated with reinforced through reinforced steel sleeve and Wang Liang's Position will be two solid steel bars linked Characteristic: Connect intensity to be high, performance reliable, can bear high stress draw and pigeonhole the load and tired load repeatedly.
New technique of the computer network Abstract The 21 century is an ages of the information economy, being the computer network technique of representative techniques this ages, will be at very fast speed develop soon in continuously creatively, and will go deep into the people's work, life and study. Therefore, control this technique and then seem to be more to deliver the importance. Now I mainly introduce the new technique of a few networks in actuality live of application. keywords Internet Network System Digital Certificates Grid Storage 1. Foreword Internet turns 36, still a work in progress Thirty-six years after computer scientists at UCLA linked two bulky computers using a 15-foot gray cable, testing a new way for exchanging data over networks, what would ultimately become the Internet remains a work in progress. University researchers are experimenting with ways to increase its capacity and speed. Programmers are trying to imbue Web pages with intelligence. And work is underway to re-engineer the network to reduce Spam (junk mail) and security troubles. All the while threats loom: Critics warn that commercial, legal and political pressures could hinder the types of innovations that made the Internet what it is today. Stephen Crocker and Vinton Cerf were among the graduate students who joined UCLA professor Len Klein rock in an engineering lab on Sept. 2, 1969, as bits of meaningless test data flowed silently between the two computers. By January, three other "nodes" joined the fledgling network.
Constant pressure water supply frequency changer The transistor frequency changer not only overcame has formerly exchanged velocity modulation many shortcomings, moreover the velocity modulation performance might compare favorably with the direct current motor velocity modulation performance. The three-phase asynchronous motor has the service to be convenient, merit and so on price small advantage, power and rotational speed adapt breadth, its frequency conversion velocity modulation technology in the miniaturization, the low cost and the redundant reliable aspect holds the obvious superiority. To the end of the 80's, the alternating current machine frequency conversion velocity modulation technology rapidly develops into a mature technology, it will supply the alternating current machine the labor frequency alternating current supply to turn direct current after the diode rectification, again by component and so on IGBT or GTR module counter will turn the alternating current supply which the frequency might move, will drive the electrical machinery by this power source to move under the speed change condition, and automatic suitable strain load condition. After it changed in the traditional industry the electrical machinery to start only can by the rated power, decide the rotational speed the sole movement way, thus achieved the energy conservation goal. The modern frequency conversion velocity modulation technology applies in the electric power water pump water supply system. Because the frequency conversion velocity modulation has the velocity modula -tion the physical characteristics well, efficiency high, velocity modulation scope -wide, precision high, adjusting character curve smooth, may continual realize, the steady velocity modulation, the volume small, the maintenance simple is conven -ient, the automated level higher a series of prominent merits but time people's favor. When it applies especially in the air blower, the water pump and so on the large capacity load, may obtain the energy conservation effect which other velocity modulation ways is unable to compare. The frequency conversion velocity modulation system main equipment is provides the frequency conversion power source the frequency changer, the frequency changer may divide into exchange - direct current - to exchange the frequency changer and the exchange - exchan
本科毕业设计（外文翻译） 题目居住区交往空间规划与设计 院（系部）xxx学院 专业名称xx 年级班级xx 学生姓名xx 指导教师xx xx 年xx 月x 日 Planning and Design of Association Space of residential District
Xia dong liang 【Abstract】:The association space refers to the indoor and outdoor space for communication between residents.The article presents an overall discussion of the necessity，hierarchy and functionality of association space,with a wish to create positive and healthy association atmosphere and stimulate good communication among residents so that the residential area can become a homeland full of love and harmony． 【Keyword】:residential area；association space；necessity；hierarchy；Functionality 【Foreword】：As the housing system reform and the rapid development of real estate, urban residential areas large urban settlements have emerged on the layout of residential buildings, public buildings, public green space, life and living facilities such as roads, to provide urban residents live in the community and The establishment, is an integral part of the city. Exchanges between the living room area residents is to communicate and exchange of indoor and outdoor space. At this stage, people's living standards greatly improved the living environment of continuous improvement district. Developers should not only focus on residential construction and the reasonable comfort, paying greater attention to the construction of residential environment. However, the current environment in the construction of residential areas, they are often the natural ecology of greening the environment is much more to consider, and the promotion of exchanges between the residents of the space environment to consider less, environmental construction can not meet the occupants of the psychological characteristics and needs. From the basic physiological needs gradually to meet the psychological and cultural fields of promoting a higher level, the residential area is not only the function of living, but also people's thinking and feelings of the local exchange. Therefore, the strengthening of exchanges between the residential areas of space construction, increase residential neighbourhood affinity, should be developed in the planning and construction of residential areas should also consider the issue. How to conduct exchanges between the residential areas of space planning and design, improve people's quality of life, the author of his own real estate development
Study on Project Cost Control of Construction Enterprises By: R. Max Wideman Abstract With the increasing maturity of construction market, the competition between construction enterprises is becoming fierce. The project profit is gradually decreasing. It demands that all construction enterprises enhance their cost control, lower costs, improve management efficiency and gain maximal profits. This paper analyses the existing problems on project cost control of Chinese construction enterprises, and proposes some suggestions to improve project cost control system. Key Words ：Construction enterprises, Project management, Cost control After joining the WTO, with Chinese construction market becoming integrated, the competition among architectural enterprises is turning more intense. Construction enterprises must continually enhance the overall competitiveness if they want to develop further at home and abroad construction market. Construction Enterprises basically adopt the "project management-centered" model, therefore, it is particularly important to strengthen project cost control. 1.The Current Domestic Project Cost Classification and Control Methods Cost refers to the consumption from producing and selling of certain products, with the performance of various monetary standing for materialized labor and labor-consuming. Direct and indirect costs constitute the total cost, also known as production cost or manufacturing cost. Enterprise product cost is the comprehensive indicator to measure enterprise quality of all aspects. It is not only the fund compensation scale, but also the basis to examine the implementation of cost plan. Besides, it can provide reference for product pricing According to the above-mentioned definition and current domestic cost classification, construction project cost can be divided into direct costs and indirect costs. Direct costs include material cost, personnel cost, construction machinery cost, material transportation cost, temporarily facility cost, engineering cost and other direct cost. Indirect costs mainly result from project management and company's cost-sharing, covering project operating costs (covering the commission of foreign projects), project's management costs (including exchange losses of
英文翻译 A comprehensive overview of substations Along with the economic development and the modern industry developments of quick rising, the design of the power supply system become more and more completely and system. Because the quickly increase electricity of factories, it also increases seriously to the dependable index of the economic condition, power supply in quantity. Therefore they need the higher and more perfect request to the power supply. Whether Design reasonable, not only affect directly the base investment and circulate the expenses with have the metal depletion in colour metal, but also will reflect the dependable in power supply and the safe in many facts. In a word, it is close with the economic performance and the safety of the people. The substation is an importance part of the electric power system, it is consisted of the electric appliances equipments and the Transmission and the Distribution. It obtains the electric power from the electric power system, through its function of transformation and assign, transport and safety. Then transport the power to every place with safe, dependable, and economical. As an important part of power’s transport and control, the transformer substation must change the mode of the traditional design and control, then can adapt to the modern electric power system, the development of modern industry and the of trend of the society life. Electric power industry is one of the foundations of national industry and national economic development to industry, it is a coal, oil, natural gas, hydropower, nuclear power, wind power and other energy conversion into electrical energy of the secondary energy industry, it for the other departments of the national economy fast and stable development of the provision of adequate power, and its level of development is a reflection of the country's economic development an important indicator of the level. As the power in the industry and the importance of the national economy, electricity transmission and distribution of electric energy used in these areas is an indispensable component.。Therefore, power transmission and distribution is critical. Substation is to enable superior power plant power plants or power after adjustments to the lower load of books is an important part of power transmission. Operation of its functions, the capacity of a direct impact on the size of the lower load power, thereby affecting the industrial production and power consumption.Substation system if a link failure, the system will protect the part of action. May result in power outages and so on, to the production and living a great disadvantage. Therefore, the substation in the electric power system for the protection of electricity reliability,
毕业设计--基于PLC的变频调速恒压供水系统（含外文翻 译） 山东科技大学学士学位论文摘要 摘要 本论文根据中国城市小区的供水要求，设计了一套基于PLC的变频调速恒压供水系统, 并利用组态软件开发良好的运行管理界面。变频恒压供水系统由可编程控制器、变频器、水泵机组、压力传感器、工控机等构成。 本系统包含三台水泵电机，它们组成变频循环运行方式。采用变频器实现对三相水泵电机的软启动和变频调速，运行切换采用“先启先停”的原则。压力传感器检测当前水压信号，送入PLC与设定值比较后进行PID运算，从而控制变频器的输出电压和频率，进而改变水泵电机的转速来改变供水量，最终保持管网压力稳定在设定值附近。通过工控机与PLC的连接，采用组态软件完成系统监控，实现了运行状态动态显示及数据、报警的查询。 关键词:变频调速，恒压供水，PLC，组态软件 山东科技大学学士学位论文 ABSTRACT ABSTRACT According to the requirement of China's urban water supply, this paper designs a set of water supply system of frequecey control of constant voltage based on PLC, and have developed good operation management interface using Supervision Control and Data Acquisition.The system is made up of PLC, transducer,units of pumps,pressure sensor and control machine and so on.
毕业设计英文资料翻译 Tran slati on ofthe En glish Docume nts for Graduati on Desig n 课题名称_____________________________________ 院< 系）_____________________________________ 专业 _____________________________________ 姓名 _____________________________________ 学号 _____________________________________ 起讫日期 _____________________________________ 指导教师 _____________________________________ 2018 年2月25日 原文: Abstract：Gree n buildi ng refers to do its best to maximize con servati on of resources (en ergy, land, water, and wood> , protecti ng the environment and reduce polluti on in its life cycle. Provide people with healthy, appropriate and efficient use of space, and nature in harmony symbiosis buildings. Idescribed more details of green building design ' notion, green building ' design, as well as the sig ni fica nee of the con
（ 二 〇 一 二 年 六 月 外文文献及翻译 题 目： About Buiding on the Structure Design 学生姓名： 学 院：土木工程学院 系 别：建筑工程系 专 业：土木工程(建筑工程方向) 班 级：土木08-4班 指导教师：
英文原文： Building construction concrete crack of prevention and processing Abstract The crack problem of concrete is a widespread existence but again difficult in solve of engineering actual problem, this text carried on a study analysis to a little bit familiar crack problem in the concrete engineering, and aim at concrete the circumstance put forward some prevention, processing measure. Keyword:Concrete crack prevention processing Foreword Concrete's ising 1 kind is anticipate by the freestone bone, cement, water and other mixture but formation of the in addition material of quality brittleness not and all material.Because the concrete construction transform with oneself, control etc. a series problem, harden model of in the concrete existence numerous tiny hole, spirit cave and tiny crack, is exactly because these beginning start blemish of existence just make the concrete present one some not and all the characteristic of quality.The tiny crack is a kind of harmless crack and accept concrete heavy, defend Shen and a little bit other use function not a creation to endanger.But after the concrete be subjected to lotus carry, difference in temperature etc. function, tiny crack would continuously of expand with connect, end formation we can see without the