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31.
The development of complex, flexible manufacturing systems (FMS) is very much dependent on the development of the associated control software. Because of the complexity involved, reliable and quality FMS software with comprehensive functionality and sophistication is difficult to design, implement and maintain. This paper proposes a modular, generic software system. Using the software developed, a range of cellular FMS (CFMS) control software can be generated from a library of well-defined software building blocks. This paper also describes the design of a generic software architecture, covering specifications for the control architecture, controller structure and software platform. Application of the building block concept has addressed the CFMS software problem effectively and the resulting software possesses a high degree of modularity and flexibility. 相似文献
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Abstract A relatively simple technique for the prediction of the thermal conductivity of polar organic fluids over the temperature range from 0° to 100°C is presented. The proposed model is basically derived via the generalized property correlation model developed by Riazi and Daubert in 1980. The method requires, as input, only normal boiling point, specific gravities and dipole moments or acentric factors for each compound of interest. Predicted thermal conductivities are compared with 93 literature data for 12 polar liquids. Average deviation between prediction and experiment is approximately within 8–12%, depending on the type of third input parameter, as opposed to 17% for the much involved method of Robins and Kingrea previously recommended. 相似文献
33.
Che-Wei Chang Shia-Chung Chen Pi-Lin Tsai Min-Chi Chiu Yu-Shiu Liu 《Polymer Engineering and Science》2021,61(6):1650-1661
The industrial developments have led to more applications of various composites. Since fiber orientation and distribution will influence product performance in composites, controlling said orientation and distribution is of critical importance. This study used external magnetic fields to control the fiber orientation and distribution in a polymer. The orientation of the actual fibers under magnetic field control during flowing was observed using a visualization system, which was made by PMMA and transparent epoxy as an upper cover and filling polymer. In order to clearly observe and calculate, 0.1 wt% fiber content was used, and 0.3 wt% fiber content was used to measure conductivity. Fiber distribution angles without a magnetic field concentrate parallel to the flow direction (0° ~ 30° and 151° ~ 180°) while distribution angles under magnetic field control were concentrated along the magnetic field direction, which was perpendicular to the flow direction (61° ~ 120°). The higher the magnetic flux density, the larger the torque of the electromagnetic field on the fibers and the higher the orientation of fibers was with the magnetic field. The electrical conductivity was 12.23 times higher for 1 mm fibers in an external magnetic field versus no magnetic field. 相似文献
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Kuo-Hsiung Tseng Juei-Long Chiu Heng-Lin Lee Yi-Syuan Kao Der-Chi Tien 《Materials and Manufacturing Processes》2016,31(2):186-193
This study developed a system monitoring the electric discharge machine's (EDM) discharge energy and success rate to replace conventional oscilloscope observation. By using logic circuit, the signals are transmitted to the PC monitoring platform in order to display the discharge success times, discharge success rate, and electrode's consumption energy. The advantage of the proposed system is the capability to observe real-time discharges and record the experimental conditions, as well as optimize the discharge parameter settings. The experimental results suggest that, in the preparation of nanosilver colloid, the cost-performance of Ton–Toff at 10–100 µs is the optimal setting. The monitoring system also can take advantage of the discharge success rate to control the energy consumption of the electrode to obtain the standardization of products. The results suggest that, while discharge success rate, electrode's weight loss and wavelength of the absorption peak are considerably accurate, but concentration accuracy is relatively poor. The discharge success rate monitoring system is an innovative method that can help to realize electric discharge processing, optimize product quality, and it may be a powerful processing tool in the future. 相似文献
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Flora W Y Chiu Hakan Bagci Amanda G Fisher Andrew J deMello Katherine S Elvira 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2016,91(1):16-24
Cellular fusion is a key process in many fields ranging from historical gene mapping studies and monoclonal antibody production, through to cell reprogramming. Traditional methodologies for cell fusion rely on the random pairing of different cell types and generally result in low and variable fusion efficiencies. These approaches become particularly limiting where substantial numbers of bespoke one‐to‐one fusions are required, for example, for in‐depth studies of nuclear reprogramming mechanisms. In recent years, microfluidic technologies have proven valuable in creating platforms where the manipulation of single cells is highly efficient, rapid and controllable. These technologies also allow the integration of different experimental steps and characterisation processes into a single platform. Although the application of microfluidic methodologies to cell fusion studies is promising, current technologies that rely on static trapping are limited both in terms of the overall number of fused cells produced and their experimental accessibility. Here we review some of the most exciting breakthroughs in core microfluidic technologies that will allow the creation of integrated platforms for controlled cell fusion at high throughput. © 2015 Society of Chemical Industry 相似文献
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Wen-Kang Chen Hui-Hsin Tseng Ming-Chi Wei En-Chin Su I.-Ching Chiu 《International Journal of Hydrogen Energy》2014
A series of mesoporous Zr-SBA-15-supported Na catalysts was prepared and applied to the heterogeneous catalysis of canola oil transesterification. The effects of Si/Zr ratio, reaction time, and percentage of Na loading on the conversion to fatty acid methyl esters (FAME) were studied. The dependence of the textural structure and chemical properties of Zr-SBA-15 supports on Zr content was investigated using small-angle X-ray diffraction, Brunauer–Emmett–Teller analysis, transmission electron microscopy (TEM), and Fourier transform infrared (FTIR) spectroscopy. The results obtained from FTIR and TEM indicate that the incorporation of Zr atoms into the SBA-15 structure facilitated the formation of Brönsted acid sites and decreased the particle size of Na species. Catalysts with a higher Zr content enhanced the FAME yield. The optimum conditions determined were as follows: reaction temperature of 70 °C, 15 wt.% Na, reaction time of 6 h, and 12% catalyst content (wt.% oil) with a methanol/oil molar ratio of 6:1. The optimum conditions resulted in a FAME yield of up to 99%. 相似文献
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