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101.
Qidong Cao Mark A. Mcknew 《International Journal of Flexible Manufacturing Systems》1994,6(2):155-172
A new optimization model is discussed for the design of cellular manufacturing systems. It is based on an integer programming formulation that updates some other models by eliminating redundant machine assignment and cost coefficients dependent on cell configuration. To reduce computational burdens, a simplified integer programming model and a decomposition algorithm are proposed. Several computer solutions were performed to evaluate the performance of the new model. The computational results are discussed. 相似文献
102.
An analytical method is presented for calculating the resonant frequency andQ-factor of a superconducting dielectric disk resonator operating in millimeter-wave regime with whispering-gallery mode. Resonant frequency shift due to the optical generation of quasi-particles in superconducting film is investigated as a function of photon flux. An optically tunable resonant frequency of about 500 MHz is estimated, and good agreement is found between numerical results and experimental ones. 相似文献
103.
PURPOSE: The purpose of this research is to obtain the tablet coating distribution from weight distributions of uncoated and coated tablets. METHODS: The method of deconvolution with digital smoothing was used to calculate the distribution of coating applied to a tablet population from separate random measurements of individual uncoated and coated tablets. RESULTS: It was demonstrated that the calculated coating weight distribution agrees well with the measured distribution. The effect of the smoothing factor on the solution is illustrated. CONCLUSIONS: This method can be used during development to facilitate process scale-up/optimization. In routine production, the method can assess the reproducibility and consistency of a coating process. 相似文献
104.
105.
The author presents a personal account of the search for a design procedure for Yagi-Uda antenna arrays yielding a maximum gain, or directivity if element losses are neglected. Results on current distributions in the array are briefly reviewed. The analytical approach used to achieve gain optimization by means spacing and length perturbations is sketched. By using both spacing and length perturbations, it was possible to find the optimized array analytically in a systematic way, some examples having gain increases of nearly 80%. The effects of finite dipole radius and mutual coupling were included in the theoretical treatment 相似文献
106.
The span-depth ratios of coupling beams to interconnect shear walls are generally small, so that brittle shear failure may occur and lead to reduced ductility. In order to improve the ductility of coupling beams for earthquake loading, a new type of ductile coupling beam is proposed in this paper. Along the middle depth of this beam, a slit through the entire thickness (a narrow hole) near each end and two lateral keyways along the remaining middle part of the span are made. The reductions of the stiffness under service load and the ultimate carrying capacity of the beam due to the weakening mentioned above are small and the ductility is greatly increased. Tests of 4-storey walls interconnected by coupling beams in three different constructions (monolithic beams, beams with a through-slit and new-type beams) indicated that shear walls with the new coupling beams possess the best aseismic behaviours under cyclic loading. The proposed new coupling beam has been used in a high-rise building. 相似文献
107.
Conventional drying, dehumidification drying, and combined conventional-dehumidification drying of wood were experimentally studied in this article. The results showed that the energy consumption in the dehumidification drying is the least but its drying time is the longest. The energy consumption in the combined drying is more than that in the dehumidification drying but less than that in the conventional drying, and the drying time is half of that in the dehumidification drying. The advantages of the combined conventional and dehumidification drying are discussed from the experiments results. 相似文献
108.
109.
Two experimental devices were designed and built to determine four coefficients KT KM DM D (or δT = DT / DM occurring in simultaneous heat and mass transfer equations, where,K T and DM are thermal conductivity and moisture diffcusivity respectively, DT ( or δ T is temperature gradient Induced moisture migration coefficient and KM is moisture gradient Induced heat transfer coefficient. Three food materials, i.e. potato, bread dough and bread, were tested. From this study, it was found that the value of 5 was higher for low density food materials, such as bread, than for high density materials, such as potato. The coefficient & measures moisture migration contribution due to temperature gradient within the material. The average values of δ T for potato, bread dough and bread were 0.0014, 0.0059 and 0.0127 per °C, respectively. The contribution of temperature gradient to the overall moisture migration is negligible In high density materials. However, this contribution may be important in the moisture migratlon analysls for low density materials. The moisture gradient induced heat transfer coefficient % as found to be negligible for the materials tested in this study 相似文献
110.
To investigate the prognostic factors of primary liver cancer (PLC) and improve the long-term results, 1,248 cases of PLC were analysed. Univariate analysis demonstrated that discovery approach, staging of PLC, original gamma-GPT, resection, radical resection, original AFP, tumor size, tumor number, and tumor capsule have very significant effects on prognosis of PLC (all P < 0.001); cirrhosis, HBsAg, local resection, and tumor embolus in portal vein were also significant difference (all P < 0.05); age, sex, original AFP, hepatitis, and differentiation of PLC cells were no significant difference (all P > 0.05). Multivariate analysis demonstrated that original gamma-GPT, radical resection, tumor size, and tumor number were the most significant prognostic factors (all P < 0.001). Some aspects improving long-term survival were discussed. 相似文献