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急求英文高手翻译一段摘要 有关夹具设计的

东机近幕通ykh 2009-05-07 02:47:12 400  浏览
  • Abstract In this paper, the general situation of research on agile fixture design is summarized and the achievements and deficiencies in the field of case-based fixture design are pointed out. There are no correlative case bases and match... Abstract In this paper, the general situation of research on agile fixture design is summarized and the achievements and deficiencies in the field of case-based fixture design are pointed out. There are no correlative case bases and matching mechanisms during the period from establishing the fixture planning to designing the fixture in currently used case-based fixture design systems. Thus a great amount of experience of fixture design is wasted and cannot be re-used, which reduces design efficiency and violates the original intention of case-based reasoning methods. In order to realize agility of fixture design, including re-configurability, re-scalability and re-usability, in this paper, a re-configurable agile fixture element base and an element assembly relation base are established. Using these two bases, the fixture structure is function-based decomposed, which makes it easy for an agile fixture to be re-configured and modified. Furthermore, a whole case-based agile fixture design model is presented, in which three modules are introduced, including the evaluation of the similarity of fixture planning, conflict arbitration and the modification of an agile fixture case. The three modules can be used to solve a problem where experience and design results cannot be re-used in the process of fixture design. Against the agile fixture design model, the evaluation method is put forward to evaluate the similarity in various phases. However, a similar case in the base could not generally meet the actual requirement and resolve the conflict between the similar case and the actual condition. Thus three methods, including a local restriction-relaxed method, a function-based conflict arbitration method and a case-based conflict arbitration method, are presented to clear up the conflict and could be used to modify the case to obtain an approach to a design result. Finally, an agile fixture design example is presented. The result demonstrates that the case-based agile fixture design approach can improve re-usability and design efficiency. Keywords: Agile fixture design; Case-based reasoning; Modeling 展开

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  • 月殇忒忒rei 2009-05-08 00:00:00
    摘要 摘要研究概况的基础上,总结了敏捷夹具设计的成就和不足的领域 指出了夹具的设计实例。没有相关的案例基地和匹配机制建立的期间 夹具设计规划固定在目前使用的案例夹具设计系统。如此大量的经验的夹具 设计是浪费了,不能被重用,从而降低了设计效率和违反本意基于实例推理的方法。 为了实现敏捷的夹具设计,并在此基础上,可重新安装敏捷 夹具元件基地和元素装配关系建立基地。利用这两根、带卯的座、夹具结构 分解,从而使它容易被灵活的夹具和修改。此外,整个案例敏捷夹具设计 模型,提出了三个模块进行了较为详细的介绍,包括评估的相似性夹具规划、冲突仲裁 和修改一个灵活的夹具的案例。这三个模块也可以被用来解决问题的经验和设计结果不能 在这个过程中,重复夹具设计。对夹具设计模式,灵活的评价方法,提出了评价相似 在各种不同的发展阶段。然而,一个类似的案件中不可能满足实际需要,一般解决冲突 类似的情况和实际情况。这样的三种方法,包括当地r冲突法仲裁 方法及推理的方法,给出了冲突仲裁的冲突,并可用来修改这个案件能够获得 方法设计的结果。Z后,一个灵活的夹具设计的例子。实验结果表明,该案例敏捷夹具 设计方法能够提高设计效率。 关键词:敏捷夹具设计;基于实例推理、建模

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急求英文高手翻译一段摘要 有关夹具设计的
Abstract In this paper, the general situation of research on agile fixture design is summarized and the achievements and deficiencies in the field of case-based fixture design are pointed out. There are no correlative case bases and match... Abstract In this paper, the general situation of research on agile fixture design is summarized and the achievements and deficiencies in the field of case-based fixture design are pointed out. There are no correlative case bases and matching mechanisms during the period from establishing the fixture planning to designing the fixture in currently used case-based fixture design systems. Thus a great amount of experience of fixture design is wasted and cannot be re-used, which reduces design efficiency and violates the original intention of case-based reasoning methods. In order to realize agility of fixture design, including re-configurability, re-scalability and re-usability, in this paper, a re-configurable agile fixture element base and an element assembly relation base are established. Using these two bases, the fixture structure is function-based decomposed, which makes it easy for an agile fixture to be re-configured and modified. Furthermore, a whole case-based agile fixture design model is presented, in which three modules are introduced, including the evaluation of the similarity of fixture planning, conflict arbitration and the modification of an agile fixture case. The three modules can be used to solve a problem where experience and design results cannot be re-used in the process of fixture design. Against the agile fixture design model, the evaluation method is put forward to evaluate the similarity in various phases. However, a similar case in the base could not generally meet the actual requirement and resolve the conflict between the similar case and the actual condition. Thus three methods, including a local restriction-relaxed method, a function-based conflict arbitration method and a case-based conflict arbitration method, are presented to clear up the conflict and could be used to modify the case to obtain an approach to a design result. Finally, an agile fixture design example is presented. The result demonstrates that the case-based agile fixture design approach can improve re-usability and design efficiency. Keywords: Agile fixture design; Case-based reasoning; Modeling 展开
2009-05-07 02:47:12 400 1
翻译一段纳米材料的摘要(1)
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2011-06-20 08:50:55 322 1
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2013-12-03 16:23:25 225 2
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2013-06-11 09:00:02 456 3
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2018-11-17 09:10:28 391 0
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2014-12-28 15:14:51 493 1
急求翻译
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2011-05-20 09:09:32 273 2
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2009-05-15 15:29:46 328 2
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2010-06-19 21:53:22 469 1
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2009-11-18 12:57:13 523 1
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2009-03-24 13:04:22 299 2
急求翻译毕业论文
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2018-11-26 09:40:00 244 0
翻译纳米材料摘要(2)
Moreover, the particle size of incorporated ZnO calculated from the effective mass model was close to the results obtained from HRTEM. The synthesis method developed in course of this work can be used for the fabrication of different polym... Moreover, the particle size of incorporated ZnO calculated from the effective mass model was close to the results obtained from HRTEM. The synthesis method developed in course of this work can be used for the fabrication of different polymer-inorganic transparent nanocomposites with other functionalities. In the second part of the thesis, we studied a method for the fabrication of micro-porous surface layer – made of copper nanoparticles – on the surface of copper plates (suitable for heat exchangers). The micro-porous surfaces were formed from dendritic network of copper nanoparticles obtained by electrodeposition from solution using dynamic bubble formation and removal as template. The surface layer engineered and its structures were optimized in order to enhance the boiling heat transfer coefficient. To further optimize the dendritic structure, additional annealing step was introduce and its effect on the surface layer structure and properties were investigated. The properties of the deposited surface structures were investigated and its effect on the enhancement of the heart transfer coefficient has been studied. The fabricated enhanced surface has shown an excellent performance in nucleate boiling. Pool boiling tests were performed on refrigerant fluids (R134a) to evaluate the boiling performance of the electrodeposited nanostructured micro-porous structures. At heat flux of 1 W/cm2, the heat transfer coefficient is enhanced over 15 times compared to a plain reference surface. A model has been presented to explain the enhancement based on the structure characteristics. 展开
2006-10-18 01:46:56 347 4
帮忙翻译论文摘要
换热器是化工、炼油、动力、食品、轻工等许多工业部门广泛应用的一种通用设备。其性能的好坏直接影响过程工业热经济性的高低。近年来,由于能源危机,强化传热技术和新型换热器的研究... 换热器是化工、炼油、动力、食品、轻工等许多工业部门广泛应用的一种通用设备。其性能的好坏直接影响过程工业热经济性的高低。近年来,由于能源危机,强化传热技术和新型换热器的研究得了飞速发展。本次的实验是在前人设计的带螺旋折流片(下简称螺旋片)换热器的基础上再在内圆管多加上扰流柱,分析不同操作参数和结构参数条件下流体传热情况,由此得出影响换热器传热性能的条件,为进一步研究静态混合器传热情况和其在实际工程及设计中的应用奠定基础。 本文对换热器进行了研究,测得壳程空气进出口温度,利用温差传热,以努塞尔准数作为衡量换热器传热性能的标准,分别考察了雷诺数对努塞尔准数的影响,并与空管进行了比较。换热器器中由于扰流柱的作用,使进入管中的流体在流经扰流柱时产生旋涡,有效地消除了径向主流道的速度梯度和温度梯度。因传热边界层大大减薄,使得边界层内流体不断得到更新,热阻下降,传热过程得到强化。 通过实验可以得出一些结论: 由于有螺旋片同扰流柱的存在使得扰动螺旋型换热器的传热效果明显要优于圆滑管型换热器同螺旋型换热器;螺旋片使流体具有向外甩开的离心力,流体在流过扰流柱时因被分流、切割、再生,不仅加速了流速并且在柱后形成涡流,加速壁面流体的更新,减薄粘性边界层底层的厚度,从而提高了传热性能; 同一模型在不同Re下,随着Re的增加,Nu也随着增加,在不计阻力时,模型的传热效果随着Re的增加而提高 不要翻译软件翻译的。如果好再加分 展开
2018-11-25 12:54:46 362 0
帮忙翻译论文摘要
换热器是化工、炼油、动力、食品、轻工等许多工业部门广泛应用的一种通用设备。其性能的好坏直接影响过程工业热经济性的高低。近年来,由于能源危机,强化传热技术和新型换热器的研究... 换热器是化工、炼油、动力、食品、轻工等许多工业部门广泛应用的一种通用设备。其性能的好坏直接影响过程工业热经济性的高低。近年来,由于能源危机,强化传热技术和新型换热器的研究得了飞速发展。本次的实验是在前人设计的带螺旋折流片(下简称螺旋片)换热器的基础上再在内圆管多加上扰流柱,分析不同操作参数和结构参数条件下流体传热情况,由此得出影响换热器传热性能的条件,为进一步研究静态混合器传热情况和其在实际工程及设计中的应用奠定基础。 本文对换热器进行了研究,测得壳程空气进出口温度,利用温差传热,以努塞尔准数作为衡量换热器传热性能的标准,分别考察了雷诺数对努塞尔准数的影响,并与空管进行了比较。换热器器中由于扰流柱的作用,使进入管中的流体在流经扰流柱时产生旋涡,有效地消除了径向主流道的速度梯度和温度梯度。因传热边界层大大减薄,使得边界层内流体不断得到更新,热阻下降,传热过程得到强化。 通过实验可以得出一些结论: 由于有螺旋片同扰流柱的存在使得扰动螺旋型换热器的传热效果明显要优于圆滑管型换热器同螺旋型换热器;螺旋片使流体具有向外甩开的离心力,流体在流过扰流柱时因被分流、切割、再生,不仅加速了流速并且在柱后形成涡流,加速壁面流体的更新,减薄粘性边界层底层的厚度,从而提高了传热性能; 同一模型在不同Re下,随着Re的增加,Nu也随着增加,在不计阻力时,模型的传热效果随着Re的增加而提高 不要在线翻译的。希望帮一忙! 如果好再加100分,我现在非常急,马上就要交了。 展开
2018-11-16 22:06:50 358 0
【生物专业英语】摘要翻译
Abstract:Heavymetals,suchascadmium,copper,lead,chromiumandmercury,areimportantenvironmentalpollutants,particularlyinareaswithhighanthropogenicpressure.Theirpresenceinthea... Abstract: Heavy metals, such as cadmium, copper, lead, chromium and mercury, are important environmental pollutants, particularly in areas with high anthropogenic pressure. Their presence in the atmosphere, soil and water, even in traces can cause serious problems to all organisms, and heavy metal bioaccumulation in the food chain especially can be highly dangerous to human health. Heavy metals enter the human body mainly through two routes namely: inhalation and ingestion, ingestion being the main route of exposure to these elements in human population. Heavy metals intake by human populations through food chain has been reported in many countries. Soil threshold for heavy metal toxicity is an important factor affecting soil environmental capacity of heavy metal and determines heavy metal cumulative loading limits. For soil-plant system, heavy metal toxicity threshold is the highest permissible content in the soil (total or bioavailable concentration) that does not pose any phytotoxic effects or heavy metals in the edible parts of the crops does not exceed food hygiene standards. Factors affecting the thresholds of dietary toxicity of heavy metal in soil-crop system include: soil type which includes soil pH, organic matter content, clay mineral and other soil chemical and biochemical properties; and crop species or cultivars regulated by genetic basis for heavy metal transport and accumulation in plants. In addition, the interactions of soil-plant root-microbes play important roles in regulating heavy metal movement from soil to the edible parts of crops. Agronomic practices such as fertilizer and water managements as well as crop rotation system can affect bioavailability and crop accumulation of heavy metals, thus influencing the thresholds for assessing dietary toxicity of heavy metals in the food chain. This paper reviews the phytotoxic effects and bioaccumulation of heavy metals in vegetables and food crops and assesses soil heavy metal thresholds for potential dietary toxicity. 用翻译软件的免回,哥也有,真诚求助高手! 展开
2010-12-13 19:23:10 520 1
英文高手帮忙翻译一下 压力容器方面
公司接到一个压力容器图纸是英文版的想知道其中的一些意思,原文如下:一TECHNICALDATA:1.MAXIMUMALLOWABLEPRESSURE7.0BAR2.WORKINGPRESSURE5.5+/-1.0BAR3.TESTPRESSURE10.0BAR4.MAXI... 公司接到一个压力容器图纸 是英文版的 想知道其中的一些意思,原文如下: 一 TECHNICAL DATA: 1.MAXIMUM ALLOWABLE PRESSURE 7.0BAR 2.WORKING PRESSURE 5.5+/-1.0BAR 3.TEST PRESSURE 10.0BAR 4.MAXIMUM ALLOWABLE TEMPERATURE 70℃ 5.MINIMUM ALLOWABLE TEMPERATURE 0℃ 6.FLUID PREFILL(ISO VG46-HLP) 7.CORROSION ALLOWABLE 2mm 8.VOLUME 38.00L 二 TECHNICAL ACCEPTANCE: 1.CHINA DECLARATION OF CONFORMITY 2.CONFORITY ASSESSMENT PROCEDURE REPORTS 3.BILL OF MATERIALS 4.INSPECTION DOCUMENTS AND CERTIFICATES FOR USED MATERIALS 5.WELDING MAP 6.LIST OF WELDERS AND THEIR QUALIFICATION CERTIFICATES 7.NDE EXAMINATION REPORTS 8.VT AND MEASUREMENT REPORTS 9.PAINT: EXTERNAL:BLUE RAL 5015 SEMI-GLOSS FINISH INTERNAL:USE SUNCORITE 528 BY HENKEL METAL CHEMICALS TO TREAT INTERNAL SURFACE OF TANK 10.PAINT REPORT 11.TECHNICAL DOCUMENTATION AND OPERAING MANUAL 三 NOTES: 1.ALL DIMENSIONS ARE IN MILLIMETER UNLESS OTHERWISE NOTED. 2.GASKET CONTACK SURFACE OF ALL FLANGES SHALL BE FINISHED WITH 125-250 AARH. 3.INTERNAL WELD SURFACE OF INSTRUMENT NOZZLE TO BE FULLY FLUSHED. 4.PAINT INSIADE AND OUT PER OILGEAR STANDAR SOP-U-002. 5.TATAL WEIGHT OF UNIT ASSEMBLY IS 32,900LB[14,900kg]. 6.DIMENSIONS IN MM. 展开
2010-07-15 11:42:12 463 6
英语高手帮忙翻译段英文 谢谢!!
In this paper, the degradation of an azo dye Orange G (OG) on nitrogen-doped TiO2 photocatalysts has been investigated under visible light and sunlight irradiation. Under visible light irradiation, the doped TiO2 nanocatalysts demonstrated ... In this paper, the degradation of an azo dye Orange G (OG) on nitrogen-doped TiO2 photocatalysts has been investigated under visible light and sunlight irradiation. Under visible light irradiation, the doped TiO2 nanocatalysts demonstrated higher activity than the commercial Dugussa P25 TiO2, allowing more efficient utilization of solar light, while under sunlight, P25 showed higher photocatalytic activity. According to the X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and UV–vis spectra analyses, it was found that both the nanosized anatase structure and the appearance of new absorption band in the visible region caused by nitrogen doping were responsible for the significant enhancement of OG degradation under visible light. In addition, the photosensitized oxidation mechanism originated from OG itself was also considered contributing to the higher visible-light-induced degradation efficiency. The effect of the initial pH of the solution and the dosage of hydrogen peroxide under different light sources was also investigated. Under visible light and sunlight, the optimal solution pH was both 2.0, while the optimal dosage of H2O2 was 5.0 and 15.0 mmol/l, respectively. Azodyes, which are characterized by the presence of one or more azo bonds ( N N ), are among the most notorious widespread environmental pollutants associated with textile,cosmetic, food colorants, printing, and pharmaceutical indus-tries. Because of their non-degradability, toxicity, potential mutagenicity and carcinogenicity, wastewaters originating from these dyes production or application industries pose a major threat to the surrounding ecosystems and human beings’ health.[1–3].Environmental concerns and the need of meeting the strin-gent international standards for rejecting wastewaters has made the development of novel and cost-effective processes for the purification of azo dyes effluents an issue of major technological importance. 展开
2011-05-06 19:00:45 326 2

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