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991.
Supply chain management has offered a way to improve the industrial environment becomes more competitive. While, the commonly seen methodologies may be effective in solving the production–distribution problem only from supplier- or customer-oriented consideration, those cannot present the interactive relationship between upstream and downstream enterprises. In the competitive semiconductor industry environment, considering the viewpoints of the supplier and consumer simultaneously is particularly required, because multiple manufacturing and demanding steps are performed at separate situations, concurrently. In this paper, we propose an interaction-oriented approach, which bases on the analytic hierarchy process (AHP) methodology and proportional rule, to solve the semiconductor distribution problem with multiple quantitative and qualitative criteria. The developed approach gives an expected satisfaction for the all participators of the whole chain while the cooperative information is shared perfectly and effectively. Analysis results demonstrate the proposed methodology is efficient and effective through a real world case study.  相似文献   
992.
Electrode pitting was investigated in resistance spot welding of 1.5-mm-thick sheet aluminum alloy 5182 using a medium-frequency direct-current welder and electrodes with a tip face curvature radius of 50 mm and tip face diameter of 10 mm. Detailed investigation of the metallurgical interactions between the copper electrode and aluminum alloy sheet was carried out using scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDX) and X-ray diffraction (XRD). The results indicated that electrode degradation, which eventually leads to weld failure, proceeded in four basic steps: aluminum pickup, electrode alloying with aluminum, electrode tip face pitting, and cavitation. Since pitting and cavitation result from Al pickup and alloying, periodic electrode cleaning could extend electrode tip life by limiting the buildup of Al on the tip face. This work is part of the effort to improve electrode tip life in resistance spot welding of aluminum alloys for automotive applications.  相似文献   
993.
YbBa2Cu3O7?x (YbBCO) thick films were grown on buffered, cube-textured Nickel tapes by sol–gel dip-coating method. Yb-123 films were prepared using solutions of Yb, Ba, and Cu organometallic compounds. A solution-based Gd2O3 buffer layer was deposited by dip-coating process with excellent texture and uniformity. The texture development and surface morphology of the buffer-layer films were examined by X-ray diffraction, pole figures, and ESEM analysis. Microstructure and characterization of Yb-123 films were done by ESEM, EDS, and XRD analysis. T c and J c were conducted by four-wire measurement method  相似文献   
994.
In order to develop highly efficient upconversion (UC) material, Er3+-doped oxyfluoride glass ceramics containing BaYF5 nano-crystals were fabricated for the first time. The randomly distributed BaYF5 nano-particles with the size of nearly 25 nm precipitated from the glass matrix at about 700 °C, then tended to aggregate slightly with the increase of heating temperature, resulting in the enhancement of Er3+ UC emission in the wavelength ranging from 500 nm to 700 nm. The UC process was found very sensitive to Er3+ content: with the increase of Er3+ content from 0.5% to 1.0%, the UC intensity behaved with drastic exaltation; while further increasing Er3+ content to 2.0% resulted in a notable fluorescence quenching. Significantly, the UC efficiency of present glass ceramic preponderates notably over that of the previously reported glass ceramic containing LaF3, implying its superior UC potentiality.  相似文献   
995.
MCM/70, manufactured by Micro Computer Machines (MCM), was a small desktop microcomputer designed to provide the APL programming language environment for business, scientific, and educational use. MCM was among the first companies to fully recognize and act upon microprocessor technology's immense potential for developing a new generation of cost-effective computing systems. This article discusses the pioneering work on personal microcomputers conducted at MCM in the early 1970s and, in particular, the making of the MCM/70 microcomputer.  相似文献   
996.
针对本钢 2× 2 65m2 烧结机成品矿输送流程设计不合理而导致的烧结机频繁停机 ,通过采取合理的改进措施 ,实现了不停机倒料线 ,有效地提高了烧结机作业率和烧结矿产量 ,同时 ,烧结矿质量也有所改善  相似文献   
997.
催化裂化大油气管线阻焦剂的研究与开发   总被引:1,自引:0,他引:1  
介绍了阻焦剂的阻聚分散机理,测定了不同组分的阻焦剂对不同性质原料的阻焦效果,并考察了不同加入浓度对阻焦率以及催化裂化产品分布的影响。试验结果表明:加入50—100μg/g的阻焦剂,可使催化裂化大油气管线阻焦率达到53.7%—63.8%,同时对产品分布及产品性质无不良影响,具有技术经济可行性。  相似文献   
998.
Spray-atomized Al-7.5Mg-0.3Sc (in wt pct) alloy powders were mechanically milled at a low-energy level and at cryogenic temperature (cryomilling). The low-energy milling effectively generated a nanoscale microstructure of a supersaturated face-centered cubic (fcc) solid solution with an average grain size of ∼26 nm. The nanoscale microstructure was fully characterized and the associated formation mechanisms were investigated. Two distinct nanostructures were identified by transmission electron microscopy (TEM) observations. Most frequently, the structure was comprised of randomly oriented equiaxed grains, typically 10 to 30 nm in diameter. Occasionally, a lamellar structure was observed in which the lamellas were 100 to 200 nm in length and ∼24 nm wide. The morphology of the mixed nanostructures in the cryomilled samples indicated that high-angle grain boundaries (HAGBs) formed by a grain subdivision mechanism, a process similar to which occurs in heavily cold-rolled materials. The microstructural evidence suggests that the subdivision mechanism observed here governs the development of fine-grain microstructures during low-energy milling.  相似文献   
999.
Z.P. Luo  J.H. Koo 《Polymer》2008,49(7):1841-1852
As the performance of polymer layered silicate nanocomposites strongly depends on their interior layer dispersion, quantification of the layer dispersion degree is needed. In this work, a new methodology was developed to determine the dispersion parameter D0.1, based on the measurement of the free-path spacing distance between the single clay sheets from the transmission electron microscopy (TEM) images. Several examples of exfoliated, intercalated, and immiscible composites were studied. It was found that the exfoliated composites had D0.1 over 8%, while that of intercalated composites were between 4 and 8%. In the case of intercalation, a high frequency peak appeared at a short spacing distance in the histogram, which was a characteristic of the intercalation, distinct from the exfoliation. The main utility of this TEM methodology is for the quantification of exfoliated or intercalated samples with small number of layers with stacks. The dispersion parameter D0.1 below 4% was suggested to classify as immiscible. A unique advantage of the TEM measurement is that the dispersion degree of different fillers can be counted individually.  相似文献   
1000.
钻进过程中,为实现定向控制目标,发明了地面遥控可调弯接头,它通过改变钻井液排量来使上、下花键轴在花键筒内上下滑动,由于各花键齿端部形状的特点,这一滑动会导致上、下花键筒之间发生转动,又由于上、下花键筒的转动轴线与它们的外表面不平行,就会使它们之间出现需要的各种弯角,从而在地面就能改变井下弯接头的结构弯角,满足定向控制技术的需要。整个调节过程花费时间很少,因此可节约钻井成本。  相似文献   
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