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To develop a customer-pleasing and economically and technically feasible product, it is necessary to utilize the best possible knowledge of the market, the customers, the core product technology, and the cost implications of design alternatives. It requires the concurrent involvement of team members from merchandizing, product development, and purchasing and production-engineering departments of the enterprise. The merchandizing department identifies customer needs however, considering only customers’ requirements, without technical information it is not possible to develop a feasible product. Conversely, the function-oriented designers in the product development department determine the subsystems’ weight, which are technically feasible but may ignore the qualitative issues desired by the customers. To identify the economic feasibility of the product, the purchasing and production-engineering departments calculate the estimated cost by evaluating the cost implications of the design alternatives. Therefore, to produce an economically and technically feasible product with customer pleasing quality, a trade-off among these three sets of weights is essential. Here, we propose an optimization model that assimilates three sets of weights of the subsystems to a final one. The resultant set of weights will represent the effects of concurrent cooperation among merchandizing, product development, purchasing and production-engineering departments of the enterprise.  相似文献   
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Cobalt molybdenum disulfide, (CoMoS2) catalysts are evaluated as active electrocatalysts for the production of hydrogen gas in acidic aqueous media. These highly-active hydrogen evolution reaction (HER) catalysts are obtained from pretreatment of ammonium tetrathiomolybdate (ATM) with different amines precursors, and characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM) and their surface areas are determined by Brunauer–Emmett–Teller (BET) surface area analyses. Electrochemical studies indicate that these CoMoS2 materials exhibit enhanced catalytic performance for hydrogen gas production with overpotentials ranging from 0.127 to 0.144 V, which are significant less than CoMoS2 synthesized directly from ATM under the same synthetic techniques (0.173 V). These CoMoS2 catalysts are also stable in the presence of strong acidic media after a considerably long period of time (10 h) for maintaining their efficiencies for hydrogen gas evolution.  相似文献   
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Dietary fibre components, hydration properties and antioxidant activities such as 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical scavenging, reducing power, metal chelating and 2,2′‐azino‐bis,3‐ethyl‐benzo‐thiazoline‐6‐sulphonic acid (ABTS) radical scavenging activities of persimmon peel powders using different washing treatments (tap water at 20 °C and hot water) were investigated. Peel powder obtained from hot water‐washed peels (74.95 g per 100 g) had higher dietary fibre content than tap water‐washed (65.50 g per 100 g) and unwashed (60.99 g per 100 g) peels. The higher content of total phenolic and ascorbic acid were found in peel powder obtained from unwashed peels, whereas washed peels had more β‐carotene content. The EC50 values of scavenging DPPH and ABTS radical for peel powders obtained from unwashed, tap water‐washed and hot water‐washed peels were 75.44, 142.18 and 110.17 μg mL?1 respectively and 5.31, 5.34 and 5.39 μg mL?1 respectively. Therefore, hot water washing is recommended to obtain better quality products from persimmon peel for use as a fibre supplement.  相似文献   
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Fat, alkaloid and polyphenol contents of two clones of cocoa (UIT1 and PBC 140) were removed and the remaining powder was autolyzed at pH 3.5 and 5.2. Based on the results, autolysates of UIT produced at pH 3.5 exhibited the highest ability to inhibit α-amylase activity. However, no α-glucosidase inhibition activity was observed under the conditions specified. Autolysates produced under pH 3.5 caused the highest amount of insulin secretion. In streptozotocin-diabetic rats, all cocoa autolysates significantly decreased blood glucose at 4 h. To assure that the results from the assays were not due to the polyphenols of cocoa autolysates qualitative and quantitative tests were applied. According to their results cocoa autolysates were found to be free from polyphenols. Analysis of amino acid composition revealed that cocoa autolysates were abundant in hydrophobic amino acids. It can be suggested that besides other compounds of cocoa, its peptides and amino acids could contribute to its health benefits.  相似文献   
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Topics in Catalysis - The morphology of a thin palladium film deposited on bilayer Al0.35Si0.65O2/Ru(0001), previously proposed as a two-dimensional zeolite model, is investigated using a set of...  相似文献   
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Mobile communications has seen an explosive growth in the past five years with the integration of communications devices and multimedia applications. Transport connections set up over wireless links are frequently plagued by such problems as a high bit error rate (BER), frequent disconnections of the mobile users, and low wireless bandwidth that may change dynamically. Proposed developments in B3G and 4G wireless services will further challenge researchers to come up with efficient devices that can handle the huge data transmission. Fast and low-power compression algorithms are greatly needed to accommodate the specification. This paper highlights and analyzes various next-generation image-compression algorithms developed on the basis of image transmission via a wireless channel. In addition, the performance comparisons between the proposed hardware implementations are shown. Two important findings are discovered: First, the high-speed reconfigurable devices called FPSoC are the best hardware implementation. Second, a vector-quantization-based VSPIHT algorithm offers the best solution of parallel processing in efficient hardware architecture. This article serves as a reference point for researchers developing image-compression algorithms for next-generation mobile-communications devices. Published in Russian in Radiotekhnika i Elektronika, 2008, Vol. 53, No. 8, pp. 950–963. The text was submitted by the authors in English.  相似文献   
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Silver nanoparticles (AgNPs) were successfully synthesized from the reduction of Ag+ using AgNO3 solution as a precursor and Brassica rapa var. japonica leaf extract as a reducing and capping agent. This study was aimed at synthesis of AgNPs, exhibiting less toxicity with high antibacterial activity. The characterization of AgNPs was carried out using UV–Vis spectrometry, energy dispersive X-ray spectrometry, fourier transform infrared spectrometry, field emission scanning electron microscopy, X-ray diffraction, atomic absorption spectrometry, and transmission electron microscopy analyses. The analyses data revealed the successful synthesis of nano-crystalline Ag possessing more stability than commercial AgNPs. The cytotoxicity of Brassica AgNPs was compared with commercial AgNPs using in vitro PC12 cell model. Commercial AgNPs reduced cell viability to 23% (control 97%) and increased lactate dehydrogenase activity at a concentration of 3 ppm, whereas, Brassica AgNPs did not show any effects on both of the cytotoxicity parameters up to a concentration level of 10 ppm in PC12 cells. Moreover, Brassica AgNPs exhibited antibacterial activity in terms of zone of inhibition against E. coli (11.1?±?0.5 mm) and Enterobacter sp. (15?±?0.5 mm) which was higher than some previously reported green-synthesised AgNPs. Thus, this finding can be a matter of interest for the production and safe use of green-AgNPs in consumer products.  相似文献   
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