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为了发展社会主义商品经济.促进技术进步,改进产品质量,提高社会和企业经济效益,维护国家和人民的利益,使标准化工作适应社会主义现代化建设和发展对外经济关系的需要,国家制定了标准化法。以法律的形式确定了标准化工作的地位和重要性,对各行各业、对企业和个人明确了其法律责任,对违法者必予以追究。国家及有关部门制定了各种各样的标准,从而保障了人民生命财产的安全,保护了消费者的利益,保护了环境。使国家资源能合理地利用,科学技术成果得到了推广,提高了经济效益,使许多产品能通用互换,做到了技术上先进,经济上合理,… 相似文献
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某(集团)公司在煤气鼓风机控制系统采用了变频技术,提高了煤气收集质量,保证了冷鼓,硫铵,粗苯等生产系统的正常工作,消除了因煤气纯度带来的潜在危险,使自动化管理水平得到提高,节省了电费开支,同时还延长了风机,元件及控制设备的使用寿命,效果十分显著。 相似文献
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本文叙述了厚壁持环铸钢件,经过工艺研究,改进了补贴和冷铁的设置,采用了保温冒口,从而消除了铸件产生疏松的隐患,保证了铸件质量,提高了工艺出品率。并经计算机凝固模拟确证了新工艺的合理性。 相似文献
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魏守武 《能源技术(上海)》2004,25(2):84-85
真空除氧冷凝系统原采用混合式冷凝器,给系统运行带来许多问题,重新设计计算后,系统改用表面式换热器,不但完全达到了原先要求的工艺指标,而且,停用了新鲜水,回收了蒸汽的余热,改善了工人的劳动条件,取得了较好的经济效益和社会效益。 相似文献
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针对兰州超高压输变电公司科研项目管理模式进行了研究与分析,提出了科研项目分解的方案,通过本方案明确了基本课题,可以较为全面、系统指导科研工作的开展,增强了科研项目实施的可操作性。构建了矩阵式科研项目管理组织结构,优化配置了公司各科研资源,明确了科研项目的各主要责任主体。确立了科研项目管理流程,做到闭环控制,加强了科研项目过程管理。 相似文献
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近年来,综合自动化保护已在变电所中广泛应用,继电保护的运行可靠性有了很大的提高,但在综合自动化保护的设计中,存在一些缺陷,阻碍了供电的可靠性。为此,分析了出现问题的原因,经过大量试验的检验,改进了原设计及接线,并在现场进行了应用。 相似文献
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阐述了PDM系统的功能,现代企业利用该系统对数据进行分类管理,缩短了新产品开发周期,降低了产品成本,提高了企业的管理能力,促进了企业的发展。 相似文献
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通过对某热电厂制粉系统排粉机及其出口风箱振动原因分析,实施了排粉机改造的治理措施,消除了制粉系统振动,保证了温风送粉系统正常投入运行,降低了锅炉排烟温度,提高了锅炉效率,节约了能源,为该厂锅炉长周期的安全经济运行奠定了良好基础。 相似文献
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Sverine Gomes Nathalie Trannoy Philippe Grossel Franoise Depasse Claudine Bainier Daniel Charraut 《International Journal of Thermal Sciences》2001,40(11):1794
The used Scanning Thermal Microscopy (SThM) probe is a thin Pt resistance wire acting as a heat source and as a detector simultaneously. Its energetic balance is investigated by the study of the temperature profile along the probe. A theoretical approach of the measurement, based on this investigation, is then proposed. Simulations with this modelling are shown to predict how the heat, electrically produced in the probe, is dissipated in the probe-sample system. In particular, it is shown that the steady-state of conduction losses to the thermal element support varies versus the thermal conductivity of the sample and can lead to bad interpretations of the measurement. 相似文献
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The establishment of a reasonable physical model and an effective solution scheme for the thermal corridor is very important to thermal protection structure design, trajectory selection, aerodynamic configuration optimization design, etc. The concept of a thermal corridor for a hypersonic vehicle was analyzed and a physical model was proposed in this paper. Furthermore, the governing equations and the corresponding algorithm for the thermal corridor were discussed. The envelopes of the height–velocity curves at typical positions of the vehicle X43 were calculated, the characteristics of the thermal corridor were summarized, the effect of the thermal protection material on the thermal corridor was discussed, and the emission coefficient of the thermal protection material was defined. The results indicate that the thermal corridor depends on the emission coefficient of the surface material, the flow conditions, and turbulence transition position. © 2008 Wiley Periodicals, Inc. Heat Trans Asian Res, 37(4): 218–223, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20203 相似文献
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Richard Garrelts Amy Marconnet 《Nanoscale and Microscale Thermophysical Engineering》2015,19(4):245-257
Nanosecond time-domain thermoreflectance (ns-TDTR) is an all optical method of determining independently a variety of thermal parameters of both homogeneous and layered materials. Despite its relative experimental simplicity, the sensitivity of the temperature decay (measured by the transient reflectivity signal) to the relevant thermal properties has yet to be fully characterized. In principle, it is possible to simultaneously extract multiple thermal parameters from a single measurement. In practice, however, changes to several of these parameters may result in experimentally indistinguishable variations to the transient reflectivity signal. In this work, we focus on investigating thermal properties of bulk material and the contact resistance between the thin-film coating that is needed for the ns-TDTR method and the bulk substrate. To extract multiple properties from one temperature decay trace, we divide the data into temporal sub-regions known to be influenced to different degrees by each individual thermal parameter and iteratively fit with a 1-D heat conduction model to independently determine the contact resistance and cross-plane thermal conductivity. 相似文献
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The application of thermal microscopes to the measurement of local thermal properties has drawn considerable scientific interest. We report on the application of a thermal microscope to the measurement of thermal effusivity for films comprising alumina deposited on a substrate, which were fabricated by an electrophoretic deposition method. The measured data was analyzed to consider the undulations on the sample surface The thermal effusivity of these samples was approximately 1×103 Js?0.5m?2K?1; this value is smaller than that for dense alumina because the alumina grain makes contact with a point. © 2008 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20227 相似文献
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Periklis E. Ergatis Panagiotis G. Massouros Georgia C. Athanasouli George P. Massouros 《国际能源研究杂志》2003,27(9):795-811
A time‐dependent coefficient of heat transfer is proposed for the computation of thermal power required, so that a room temperature reaches a desired value within a given time. A mathematical formulation of the room heating transient phenomenon is constructed in a dimensionless form. Using an integral approximate solution an analytical expression for this coefficient is provided and it is verified by diagrams adopted by DIN 4701. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
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