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101.
This article develops and tests a model examining the relationship between firm globalization, scope of e-commerce use, and firm performance, using data from a large-scale cross-country survey of firms from three industries. We find that globalization leads to both greater scope of e-commerce use and improved performance, measured as efficiency, coordination, and market impacts. Scope of e-commerce use also leads to greater firm performance of all three types. Globalization has differential effects on B2B and B2C e-commerce, however, such that highly global firms are more likely to do B2B but less likely to do B2C. Our findings provide support for Porter's (1986) thesis that upstream business activities (namely, B2B) are more global while downstream business activities (B2C) are more local or multidomestic.  相似文献   
102.
This paper presents a newly developed digital redesign control scheme with a weighted switching strategy and output-reference tracking, for a cascaded analog system with state saturation and external loads. The proposed method improves the generally poor transition response and output deviation caused by state-saturation constraint and external loads. It replaces an existing or theoretically well-designed analog controller with state saturation, by a digital controller with almost identical performance.  相似文献   
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We extend debates about the sources of university capabilities at research commercialization. Drawing upon quantitative data for a panel of 89 research-intensive US universities and interview data from two academic licensing offices, we model the relationship between technology transfer experience, embeddedness in biotechnology industry networks, basic science quality and capacity, and citation impact measures of university life science patents. Technology licensing officers draw upon the expertise of corporate partners to evaluate the potential impact of invention disclosures. The information gleaned through network ties to industry enables well-connected institutions to develop higher impact patent portfolios. Reaping the benefits of such connections, however, requires experience in balancing academic and corporate priorities to avoid the danger of ‘capture’ by industrial interests as overly tight connections limit patent impact. This pattern of diminishing returns to connectivity is robust across multiple citation measures of patent quality.  相似文献   
105.
In this paper, a modified adaptive neural network for the compensation of deadzone is described, and simulated on a hydraulic positioning system, in which the dynamic model is separated into a series of connection of a nonlinear (deadzone) subsystem and a linear plant. The proposed approach uses two neural networks. One is the radial basis function (RBF) neural network, which is used for identifying parameters of deadzone. Based on the penalty function used in optimization theory, a multi-objective cost function with constraint is adopted to provide the best deadzone approximation. The result is used to train the other neural network for the inverse compensation of deadzone. The RBF neural network also generates the parameters of the linear plant for the design of an adaptive controller. A convergence analysis for the network training process is also presented.  相似文献   
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In this study, the effect of steel fibers coated with chemically reactive enamel (CRE) on the system response of concrete structures with reinforcing bars has been investigated for the first time. In particular, the ultimate strength, ductility, and failure mechanism of 24 reinforced concrete slabs were experimentally characterized under static and blast loads. CRE coating applied on steel bars reduced the crater area of slabs under blast loads by up to 20%; it slightly increased the strength of slabs and significantly reduced the strength degradation of slabs when increasingly deflected under static loads, making the slabs more ductile. CRE coating applied on steel fibers increased the strength of slabs by up to 16% under static loads. The influence of CRE coating applied on both steel fibers and bars may be taken into account by introducing a coating factor in the range of 0.57<β<1.0 in the American Concrete Institute (ACI) development length equation.  相似文献   
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Research in Science Education - The aim of this study was to investigate whether and how engaging with a computer-supported collaborative knowledge-building environment helps students to develop a...  相似文献   
110.
We are:gOod friends.Wemust helD each other.If wemeet anY beast,I’11 help you.(我们是好朋友,应该互相帮助。如果我们遇到野兽,我将帮助你。) f$圣冀 rll help you,too.(我吐三将帮助你。) 1.One day,two young menare walkinginabig forest.卜一天,两个年轻人在森林里散  相似文献   
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