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51.
Yau-Ren Shiau 《国际生产研究杂志》2013,51(8):1787-1806
Producing high-quality products at low cost is always one concern for a multi-stage manufacturing system. That is, production costs and inspection efficiency should receive equal importance. Inspection planning to allocate inspection stations should then be performed to manage limited inspection resources during process planning. Product quality and the possible costs can then be concurrently considered when evaluating a manufacturing plan. Except for finite inspection station classes, the limited number of inspection stations of each inspection station class is considered to solve the inspection allocation problem in this research. Rather than utilizing a constant inspection error or a specified inspection error probability distribution determined by previous observations, the inspection allocation problem is solved using relative cost models in which the inspection error model is embedded. The inspection allocation problem can then be solved by practically reflecting the inspection error when tolerances are rapidly changed to satisfy customer requirements. Since determining the optimal inspection allocation plan seems impractical as the problem size becomes quite large, two heuristic methods have been developed by considering the defective rate, manufacturing cost and earliest stage priority in this research. The performance of each method is measured in comparison with the enumeration method that generates the optimal solution. A feasible manufacturing plan can then be determined and confirmed during process planning by concurrently solving the inspection allocation problem. 相似文献
52.
W. B. Doriese K. M. Morgan D. A. Bennett E. V. Denison C. P. Fitzgerald J. W. Fowler J. D. Gard J. P. Hays-Wehle G. C. Hilton K. D. Irwin Y. I. Joe J. A. B. Mates G. C. O’Neil C. D. Reintsema N. O. Robbins D. R. Schmidt D. S. Swetz H. Tatsuno L. R. Vale J. N. Ullom 《Journal of Low Temperature Physics》2016,184(1-2):396-396
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Sandalwood oil is an essential oil which finds very wide application in the flavor and fragrance, pharmaceutical industry. The objective of this study is to use the potential of near infrared spectroscopy as a rapid analytical technique for the qualitative and quantitative assessment of purity in sandalwood oils. The quality and efficacy of sandalwood oils, even though come from the same species, are somewhat different according to growing conditions (origin) and poor extraction methods. Classification of sandal oils based on their NIR spectra is performed by principal component analysis, hierarchical cluster analysis and self organising map (Kohonen neural network). All these techniques clearly differentiate the oils according to the area from which the sandalwood has been cut. Support vector machine regression (SVM R) is used to predict the purity of the oils. 相似文献
55.
Ali Rıza Kosker Joe M. Regenstein Fatih Özogul 《International Journal of Food Science & Technology》2021,56(2):874-884
The effects of season and gender on the proximate composition and fatty acid profiles of the most widespread pufferfish species in the Mediterranean Sea (Lagocephalus sceleratus, Lagocephalus spadiceus, Lagocephalus suezensis and Torquigener flavimaculosus) caught in Mersin Bay, in the north-eastern Mediterranean during four seasons were investigated. The results showed that the crude protein, lipid, moisture and ash level in pufferfish were in the range of 18.7%–21.7%, 0.61%–1.93%, 76.1%–78.6% and 1.08%–1.87%, respectively. All of the pufferfish had significant levels of polyunsaturated fatty acid (PUFA). However, the consumption of L. sceleratus, L. suezensis and T. flavimaculosus may be risky due to the possibility of having tetrodotoxin in their muscles. Nevertheless, L. spadiceus is a pufferfish species that is popularly consumed in East Asian countries, and is of nutritional interest and commercial potential in the Mediterranean region as well so its proximate composition and fatty acid profile are of interest. 相似文献
56.
Different concepts and designs of photovoltaic thermal (PV/T) collectors were developed for the past few decades to improve the electrical and thermal efficiencies. Several of those designs have become successful and are being commercialized along with other solar collectors. This paper discusses the experimental studies on a novel PV/T water-based collector constructed by laminating the PV cells on a copper thermal absorber. This modification reduced the thermal resistance by 9.93 %, thereby enabling better heat transfer from the PV cells to the heat transfer fluid. Water was passed through a single water channel connected to an open reservoir. Experiments were conducted with and without glazing, with two different water mass flow rates and stagnant conditions, and with load and no-load conditions and thermal stress test. Results show that an overall efficiency of 87.52 % was achieved in the presence of glazing at a mass flow rate of 0.1 kg/s. Few conformance tests according to IEC standards are also presented to check the electrical insulation and structural integrity of the PV/T collector. 相似文献
57.
Lijun You Lin Zheng Joe M. Regenstein Mouming Zhao Dong Liu 《International Journal of Food Science & Technology》2012,47(12):2574-2581
The effects of thermal treatment on the changes in the colour, the molecular weight distribution, amino acid profiles and the overall antioxidant activities of loach peptide were investigated. When the thermal temperature was rising, the browning was enhanced. The contents of free amino acids Gly, Arg, Thr and Tyr were increased, whereas those of Asp, Ser, Met, Cys, Trp and Lys were decreased. The scavenging activities (1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical scavenging activity, the oxygen radical absorbance capacity (ORAC) and the reducing power of loach peptides after different thermal treatments were lower than those of the control, whereas the Cu2+ chelating activity was higher (except from the sample treated at 100 °C, 20 min). The heat treatment at 121 °C, 15 min was shown to be the best thermal processing, as it caused the least loss in radical scavenging activity and showed relatively higher Cu2+ chelating activity. 相似文献
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