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Fuzzy estimation of feed-cutting force from current measurement-a case study on intelligent tool wear condition monitoring 总被引:1,自引:0,他引:1
Xiaoli Li Han-Xiong Li Xin-Ping Guan R. Du 《IEEE transactions on systems, man and cybernetics. Part C, Applications and reviews》2004,34(4):506-512
It is very important to use a reliable and inexpensive sensor to obtain useful information about manufacturing processing, such as cutting force for monitoring automated machining. In this paper, the feed-cutting force is estimated using inexpensive current sensors installed on the ac servomotor of a computerized numerical control (CNC) turning center, with the results applied to the intelligent tool wear monitoring system. The mathematical model is used to disclose the implicit dependency of feed-cutting force on feed-motor current and feed speed. Afterwards, a neuro-fuzzy network is used to identify the cutting force with current measurement only. This hybrid math-fuzzy approach will reduce the modeling uncertainty and measurement cost. Finally, the estimated cutting force is applied in the tool-wear monitoring process. Successful experiments demonstrate robustness and effectiveness of the suggested method in the wide range of tool-wear monitoring applications. 相似文献
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Potassium chloride salt pre-treated titanium silicalite-1 (TS-1) zeolite (K-TS-1) was prepared via an ion-exchange method. XRD, EDX and BET were used to identify the structure of the zeolite. The BET surface area and the adsorption/desorption cumulative pore volume of the K-TS-1 catalyst were about 297 m2/g and 0.213 cm3/g, respectively. The average pore diameter of the K-TS-1 catalyst was 29.49 Å. The catalytic activity of K-TS-1 catalyst was studied in the fixed-bed catalytic reactor. 1,4-Diazabicyclo (2.2.2) octane (DABCO) was prepared from ethylenediamine (EDA) over the K-TS-1 zeolite catalyst. The influences of various reaction parameters such as reaction temperature, space velocity and concentration of EDA were discussed. The conversion of EDA was more than 96% and the selectivity of DABCO and PIP were up to 64 and 30%, respectively, in the temperature of 340 °C and weight hourly space velocity of 1.5 h?1 in the presence of water. 相似文献
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随着单井蒸汽吞吐周期的增加,加剧了油层纵向和平面上的非均质性。汽驱井组油层存在高渗透带或孔道,注入蒸汽上升,从稠油顶部跨越,会出现越顶现象,造成提早汽窜,注蒸汽驱的波及效率进一步降低。针对此问题,开发了稠油注汽井用高温调剖封窜剂。室内研究结果表明,研制的高温调副封窜剂HD、HT具有较好的高温成胶性能和强度。现场应用孤东油田的9口井,有效8口,有效率88.9%,累计增油726.8t。 相似文献
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Veena Misra Xiaoli Xu Brian E. Hornung Richard T. Kuehn Donald S. Miles John R. Hauser Jimmie J. Wortman 《Journal of Electronic Materials》1996,25(3):527-535
In the present study, we have performed electrical characterization of oxides deposited via rapid thermal chemical vapor deposition using SiH4 and N2O. We have investigated the effect of temperature, pressure, and SiH4 to N2O ratio on the electrical and material properties of as-deposited films. We have found that as-deposited oxides deposited at low temperatures, low pressures, and with a low silane to nitrous oxide ratio of ~0.5% give good material and electrical properties. The as-deposited films are stoichiometric in nature and have high deposition rates. As-deposited films had very low Dit values, high breakdown fields, and excellent subthreshold swing. The leakage currents and metal oxide semiconductor field effect transistor current drive, although lower than thermal oxides, were found to be quite acceptable. We have also investigated the thickness dependence of the films and found that as the film thickness is reduced below 50Å, the reliability improves for all oxides including the silicon-rich deposited oxides. 相似文献
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主要介绍了自动化部近几年来在科技创新和管理方面的工作经验,如围绕莱钢生产建设全力推进技术创新;以“数字莱钢”建设为目标,加快推进莱钢信息化建设,所有这些都为莱钢提供了强有力的自动化信息化技术支撑。 相似文献
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用自制的旋臂式磨蚀实验仪,研究了5种高密度聚乙烯和1种顺丁橡胶改性的高密度聚乙烯,在铁尾矿和铁精矿浆体中的耐磨蚀性。耐磨蚀性最差的是HDPE2200J,耐磨蚀性较差的是HDPE6300M;HDPE5000s,6098和2480的耐磨蚀性较好;HDPE/cis-BR的耐磨蚀性最好。 相似文献