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1.
A series of studies of top European and other firms has revealed patterns of design management associated with commercial success. Firms that invest resources and professional expertise in product and industrial design in traditional and new industries have been commercially more successful than firms that pay less attention to these aspects of design. As an industry matures there is a shift in emphasis from design associated with technological innovation, to designs supporting technical improvements, and then to supporting user needs, fashion and product variants. These issues are illustrated through the history of the evolution of the bicycle.  相似文献   
2.
Action calculi, which generalise process calculi such as Petri nets, π-calculusand ambient calculus, have been presented in terms of action graphs. We here offer linear action graphs as a primitive basis for action calculi. This paper presents the category of embeddings of undirected linear action graphs without nesting, using a novel form of graphical reasoning which simplifies some otherwise complex manipulations in regular algebra. The results are adapted in a few lines to directed graphs. This work is part of a long-term search for a uniform behavioural theory for process calculi. Received October 2000 / Accepted in revised form April 2001  相似文献   
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A total of 188 employed mothers and fathers and their 5–7 yr-old child participated in a study of the relations between the nature of adults' work and their parenting attitudes and behaviors (a line of research influenced by both socialization and stress perspectives). In general, positive features of work (i.e., complexity of work with people, challenge, and stimulation) tended to be associated with both self-report and observational measures of developmentally sound parenting (e.g., less harsh discipline, more warmth and responsiveness). Interaction effects indicated that gender of parent and child further condition these relations. Analyses partially support the interpretation that conditions of work influence parenting through their effect on mood but also suggest that certain conditions of work may directly socialize behavior in the parental role (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Infants were presented with a moving object under 2 lighting conditions to investigate the role of vision in early reaching. The motion of the target object also allowed for an analysis of the infants' ability to use a predictive style of reaching. Infants were tested twice, at 5 and 7.5 months of age, with a moving object in the light and the same object painted with luminescent paint in the dark. Infants successfully contacted the glowing object on about half of their attempts at both ages, although 7.5 month-olds reached more often. Infants also took into account the motion of the target object by aiming their reaches ahead of the object and by reaching with their contralateral hand. These results suggest that proprioceptive feedback and sight of the target allow for successful reaching with limited visual information, even in relatively complex reaching tasks. The infants' success also demonstrates their ability to adapt their movements and reaching strategy to the speed and trajectory of the target object in order to reach predictively. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
The 29Si MAS NMR spectra of the 2H, 4H, 6H, and 3C polytypes of silicon carbide are presented. An attempt is made to correlate differences in the chemical shifts with local atomic environment. The results of the analysis of the spectra of pure polytypes are used as a basic for the interpretation of the spectra of mixed polytypes and a discussion of the crystallinity and impurity levels of different samples. Carbon-13 chemical shifts obtained from spectra of the same polytypes are also tabulated.  相似文献   
7.
All fields of engineering, whether chemical, civil, electrical, materials, mechanical, etc., encompass a common body of essential mathematics and science. In the freshman year of Drexels E4 program, this common mathematical and scientific foundation is cultivated in the Mathematical and Scientific Foundations of Engineering I, II and III (MSFE I, MSFE II, MSFE III). In an integrated fashion, MSFE I presents the essential calculus, physics and engineering mechanics vital to the freshman engineering student. In the first two quarters, MSFE II presents chemistry with clearly defined engineering applications and significance: in the third quarter, MSFE II presents living systems with the same thrust. Also in the third quarter, MSFE III presents basic circuits and circuit elements, and a brief introduction to electromagnetic theory.  相似文献   
8.
Microstructure effect of Cu/low-k interconnect, which is substantially affected by process condition or manufacturing deviation, is a dominated factors for copper stress and critical to the formation of stress-induced voiding (SIV). In this work, SIV at via bottom is studied in the aspects of thickness variation of copper interconnect and low-k dielectric. Besides, via-related factors consist of via profile and dimension are also involved in SIV sensitivity studies. With the assistance of finite element analysis (FEA), Cu stress in terms of different Cu/low-k microstructure scenarios are modelled to understand the voiding evolution and explore the their dependence with SIV susceptibility. Meanwhile, microstructure effects with and without redundant via are also simulated to evaluate their impacts on SIV immunity.  相似文献   
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The analysis and modeling of tube-hydroformed components is more complicated than that employed for sheet-metal panels, due to the lengthier process sequence and variable strain path—from flat-rolled sheet to tube; from straight tube to bent tube; and from bent tube to hydroformed component. These additional process steps make it difficult to determine whether post mortem analyses of tube failure during hydroforming can, and should, be conducted with the same tools and databases as used for simple stampings. To provide a partial answer, the properties of commercially fabricated welded straight tubes were evaluated using a free-expansion internal pressure test and compared with those of free-expansion internal pressure tests on bent tubes. The results demonstrated that the behavior of the bent tube was consistent with the mechanical properties of the as-received tube, provided due notice was accorded to the complex strain history of the bent tube. However, due to the strain-path changes occurring at the failure location, conventional approaches for monitoring strain history would yield (apparently) anomalous results.  相似文献   
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