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71.
Bruce G. Cameron Edward F. Crawley Jakub Kwapisz Alicia McNeill 《Engineering Management Journal; EMJ》2017,29(3):128-139
Platforming has become an important means of cost-sharing among industrial products. However, many firms face systemic downward pressure on commonality, with the result that many platforms realize less commonality than intended. Past research has hypothesized that divergence is the result of conflicting tensions between product customization/optimization and cost control. This article investigates the control and incentive levers available to platform managers to shape the behavior of the organization when divergence opportunities arise. Management levers are drawn from a series of 12 industrial case studies, stemming from investigations of the causes of divergences. These management levers are categorized as technical levers, financial levers, and organizational levers. This article illustrates each of the management levers with examples from the case studies. 相似文献
72.
Alena Reznickova Zdenka Kolska Jakub Siegel Vaclav Svorcik 《Journal of Materials Science》2012,47(17):6297-6304
Grafting of gold nanoparticles and nanorods on the surface of polymers, modified by plasma discharge, is studied with the aim to create structures with potential applications in electronics or tissue engineering. Surfaces of polyethyleneterephthalate and polytetrafluoroethylene were modified by plasma discharge and subsequently, grafted with 2-mercaptoethanol, 4,4′-biphenyldithiol, and cysteamine. The thiols are expected to be fixed via one of –OH, –SH or –NH2 groups to reactive places on the polymer surface created by the plasma treatment. “Free” –SH groups are allowed to interact (graft) with gold nanoparticles and nanorods. Gold nano-objects were characterized before grafting by transmission electron microscopy and UV–Vis spectroscopy. X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), and electrokinetic analysis (zeta potential determination) were used for the characterization of polymer surface at different modification phases. It was proved by FTIR and XPS measurements that the thiols were chemically bonded on the surface of the plasma-treated polymers, and they mediate subsequent grafting of the gold nano-objects. On the surfaces, modified polymers were indicated some objects by AFM, size of which was dramatically larger in comparison with that of original nanoparticles and nanorods. This result and the other results of UV–Vis spectroscopy indicate an aggregation of deposited gold nano-objects. 相似文献
73.
74.
Siang Chen Wu Pi Fen Lu Yu Chien Lin Pei Chung Chen Chi Mei Lee 《International Journal of Hydrogen Energy》2012
Photobiological H2 production is a promising method for renewable energy development. An innovative system that co-cultivating Rhodopseudomonas palustris WP3-5 and Anabaena sp. CH3 was carried out to estimate the effect of co-cultivation on H2 production enhancement. H2 production prolongation and enhancement were observed due to the light and metabolic compatibility of these two strains. Co-culture system served by acetate and fructose as carbon source can accumulate H2 in 140.8 mL, almost double than the sum of individuals. Moreover, the enhancement of H2 production was significantly affected by the mixed ratio of two strains. The mixed ratio (WP3-5:CH3) of 1:2 showed a highest H2 production rate in 44.8 mL-H2/L-culture/h, and both 2:1 and 1:2 exhibited a relatively high substrate conversion efficiency during the latest period of cultivation, whereas the mixed ratio of 1:1 and 3:1 only revealed a prolongation in H2 production due to metabolic compatibility of two strains. 相似文献
75.
Łukasz Szabłowski Jarosław Milewski Krzysztof Badyda Jakub Kupecki 《International Journal of Hydrogen Energy》2018,43(6):3555-3565
The idea of control strategy of SOFC operating to meet demand of a public utility building was presented. The strategy was formulated with the support of Artificial Neural Network. The network was used to predict the demand for electricity. The calculations were carried out on the example of a building of the Institute of Heat Engineering Warsaw University of Technology. The control strategy is influenced by various factors depending on changes in market conditions and operating characteristics of the cell. We can define different objective functions eg: working for own needs, for maximum profit and maximum service life. The article presents a simulation of SOFC operation for demand profile of the IHE building from the selected time period. 相似文献
76.
陈丕 《重庆理工大学学报(自然科学版)》2014,(12):113-115
翻译"等值"或等效问题是译学界长期争论的焦点问题。语言学派和文化学派分别从语言学角度和文化视角对此提出了各自的见解。比较文学变异学将翻译中的变异作为研究支点,"跨语际变异研究"成为译学研究的新范式,通过研究不同国家之间文学现象交流的变异状态,探究并揭示文学变异现象的内在规律性,对翻译研究有重要的启示意义。 相似文献
77.
光学微球谐振腔由于其具有超高的Q值及极小的模式体积等优点,在高灵敏度传感和光通信等方面得到了广泛的研究。测试了未封装和封装后微球腔谐振波长随温度的变化,实验结果表明随温度增大,谐振波长线性红移,且线性度高。二者温度系数不同,未封装时为25.6 pm/℃,封装后为4.4 pm/℃,主要原因为紫外胶的负热光系数所致。理论分析了紫外胶的热光效应,通过控制紫外胶厚度可以改变光在紫外胶中的比例,从而调节温度系数。当光在紫外胶中比例为0.1135时,温度系数变为0,可以抑制温度漂移,实现了温度补偿;该比例继续增大,温度灵敏度提高。低温漂、高灵敏度、微型化拓宽了回音壁模式(WGM)传感器的应用潜力。 相似文献
78.
Meng‐Hui Wang Pi‐Chu Wu Wei‐Jhe Jiang 《IEEJ Transactions on Electrical and Electronic Engineering》2015,10(4):479-486
Distribution panels are an important piece of equipment in power systems. Maintaining a loading panel and ensuring security are not easy because the power supply cannot be interrupted in high‐tech factories. Distribution panels need fully functional condition monitoring and fault diagnosis systems to prevent accidents and reduce maintenance costs. In this paper, a new scheme is proposed to design an auto‐diagnosis tool for electrical distribution panels using infrared thermography to build diagnostic features using the matter‐element model. The paper then presents an extension recognize method (ERM) based on extension theory to diagnose the abnormality element by using degrees of correlation between the tested pattern and the matter‐element models that have been built up. Test results show that the proposed method can not only recognize the main defect element of the tested panel but also detect useful information for future trends and multi‐defect analysis by the correlation indexes. This new approach merits more attention as a tool to be used in the defect recognition problems of distribution panels, especially in high‐tech factories in Taiwan. © 2015 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
79.
The formation of the S‐shaped edge‐on lamellae on the thin porous polylactic acid membrane via phase separation induced by water microdroplets 下载免费PDF全文
Ruiqing Hu Yuping Pi Na Wang Qian Zhang Jinqi Feng Weilin Xu Xia Dong Dujin Wang Hongjun Yang 《应用聚合物科学杂志》2016,133(17)
Biodegradable polymers have received increased attention due to their potential application in the medicine and food industries; in particular, poly(lactic acid) (PLA) is a primary biopolymer because of its excellent biocompatibility and absorbability features. In this study, a porous PLA membrane was fabricated by phase separation using water microdroplets produced by an ultrasonic atomizer as a coagulation bath. The formation of S‐type clusters was attributed to the slow exchange rate between solvent and coagulant, which provided time for the movement of polymer molecules. The effect of preparation conditions on the structure of S‐type clusters, including polymer concentration in solution and ambient temperature was investigated. The PLA porous membrane prepared from water micro‐droplets with different morphology compared with the sample fabricated from distilled water has potential application in fields of tissue engineering and artificial organ generation. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43355. 相似文献
80.