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981.
A comparison is given of two exact methods for the analysis of nonlinear systems with stochastic input and stochastic parameters: the Taylor-Cauchy Transform method and the Volterra-Wiener Functional method. The final results check with each other. Examples are provided.  相似文献   
982.
It was reported earlier that intraperitoneal administration of honey had immunosuppressive activity on elicitation of allergen-specific murine antibody response as evaluated by passive cutaneous anaphylaxis and double immunodiffusion methods. In this study, the immunomudulatory effect of honey is evaluated by enzyme linked immunosorbent assay (ELISA) using ovalbumin as model allergen. It was found that ovalbumin (OVA)-specific IgG antibody responses elicited with various doses of OVA were significantly suppressed by rock bee honey (p<0.01). Honey was also found to have inhibited the production of OVA-specific IgM, IgA, IgG1, and IgG2b whereas that of IgG2a and IgG3 were not affected. Furthermore, honey also suppressed the OVA-specific total IgG antibody response in various inbred mice with different genetic background. In addition, the suppressive activity of honey was examined in different groups of mice by injecting honey at different time intervals, before and after immunization with OVA. The anti-OVA IgG antibody response was suppressed significantly when honey was injected 12 hours prior/latter to OVA injection. These results confirm the suppressive activity of honey on antibody response and suggest possible clinical application.  相似文献   
983.
影响矩作为测度单篇论著影响力的评价指标探讨   总被引:1,自引:1,他引:1  
把评价视向由针对学术主体转向针对学术客体,提出着眼于单篇论著影响力评价的影响矩指标。影响矩M被定义为单篇论著影响学者力A及其影响跨度D的乘积,M越大,影响越大。通过对测算样本集和校验样本集的数据分析,显示影响矩M与总被引C及h指数的相关系数都在0.6以上,表明影响矩可以作为测评单篇论著影响力的独立指标。  相似文献   
984.
<正>Due to its far-reaching scientific impact and broad applications, coherent resonant tunneling effect in magnetic tunnel junctions has aroused intensive interest from spintronic and semiconductor communities. Actually, resonant tunneling effect has been verified and utilized in semiconductor-based multiquantum wells, such as resonant tunneling diode and light-emitting diodes with multiple quantum wells and etc. However, coherent resonant tunneling effect through metallic multi-quantum wells has been rarely reported  相似文献   
985.
This paper is based on a study of three Confucius Institutes in Canada. The research aims to explore the nature of operations at Confucius Institutes, ranging from the selection of partnering Chinese universities, to the program planning at each individual site. Specifically, it focuses on the perceived impacts of the Confucius Institute partnership on the Canadian hosting institutions. Data was collected through interviews with key administrative staff from three Canadian universities. The theoretical framework of constructivism from international relations theory and concepts drawn from the literature on the internationalization of higher education were used to analyze the findings. Key issues revealed from the data include the host’s perception of Confucius Institutes as China’s cultural diplomacy and soft power strategy, the progression of partnerships between Canada and China over time, and university autonomy.  相似文献   
986.
A new model of running shoes which features an extreme cushioning and an oversized midsole, known as the maximalist (MAX) was launched. This design claims to provide excellent shock absorption, particularly during downhill running. This study sought to assess the effects of MAX on the external impact loading, footstrike pattern, and stride length during level ground and downhill running on an instrumented treadmill. Twenty-seven distance runners completed four 5-minute running trials in the two footwear conditions (MAX and traditional running shoes (TRS)) on a level surface (0%) and downhill (10%-declination). Average and instantaneous loading rates (ILRs), footstrike pattern and stride length were measured during the last minute of each running trial. A 12% greater ILR was observed in downhill running with MAX (p?=?.045; Cohen’s d?=?0.44) as compared to TRS. No significant difference was found in the loading rates (p?>?.589) and stride length (p?=?.924) when running on a level surface. Majority of runners maintained the same footstrike pattern in both footwear conditions. Findings of this study suggested that MAX might not reduce the external impact loading in runners during level and downhill treadmill running. Instead, this type of footwear may conceivably increase the external impact loading during downhill treadmill running.  相似文献   
987.
This paper explores a Compressive Privacy (CP) methodology for optimal tradeoff between utility gain and privacy loss. CP represents a dimension-reduced subspace design of optimally desensitized query that may be safely shared with the public. Built upon the information and estimation theory, this paper proposes a “differential mutual information” (DMI) criterion to safeguard the privacy protection (PP). Algorithmically, DMI-optimal solutions can be derived via the Discriminant Component Analysis (DCA). Moreover, DCA has two machine learning variants (one in the original space and another is the kernel space) good for supervised learning applications. By extending the notion of DMI to the utility gain and privacy loss, CP unifies the conventional Information Bottleneck (IB) and Privacy Funnel (PF) and lead to two constrained optimizers, named Generalized Information Bottleneck (GIB) and Generalized Privacy Funnel (GPF). In the supervised learning environments, DCA can be further extended to a DUCA machine learning variant to reach an optimal tradeoff between utility gain and privacy loss. Finally, for fast convergence, a golden-section iterative method is developed particularly for solving the two constrained optimization problems: GIB and GPF.  相似文献   
988.
This work presents a neural identifier-control scheme for uncertain nonlinear discrete-time systems with unknown time-delays. This scheme is based on a neural identifier to get a model of the system and a discrete-time block control technique based on sliding modes to generate the control law. The neural identifier is based on a Recurrent High Order Neural Network (RHONN) trained with an Extended Kalman Filter (EKF) based algorithm. Applicability is shown using real-time test results for linear induction motors. Also, a Lyapunov analysis is added in order to prove the semi-globally uniformly ultimately boundedness (SGUUB) of the proposed neural identifier-control scheme.  相似文献   
989.
This study investigates how R&D subsidy and non-R&D subsidy affect entrepreneurial firms’ initial public offering (IPO) performance in an emerging economy like China. Analyzing data from 269 IT (information technology) entrepreneurial firms in China, we found that R&D subsidy has an inverted U-shape effect on IPO performance, while non-R&D subsidy has a positive effect on IPO performance. Furthermore, both state ownership and patent intensity moderate the inverted U-shape relationship between R&D subsidy and IPO performance. In contrast, neither of them moderates the positive relationship between non-R&D subsidy and IPO performance. These findings contribute to the literature on the effectiveness of government subsidy by highlighting the symbolic effect of government subsidy on external financing in emerging economies, and offer important practical implications to entrepreneurial firms and government funding agencies in China.  相似文献   
990.
Technological innovations often involve collaboration among firms from diverse industries. Existing literature has largely viewed participant diversity as a conduit for non-redundant information or complementary resources, thereby affecting the ex-post outcomes of innovation projects. However, it is seldom examined how projects are initially evaluated during the resource competition stage. In this study, we develop a theory of diversity as a cognitive primer, asking how collaborators from diverse backgrounds may affect external reviewers’ ex-ante evaluation of potential merits of an innovation project. We argue that there are two logics at work in the process of evaluating innovations: the logic of technological advancement and the logic of market value. When an innovation project involves firms from diverse industries, it may be perceived as having a fuzzier market identity, hence making it less appealing to reviewers who hold with the strong market value logic. However, the penalty associated with participant diversity should be less pronounced among reviewers who hold the technological advancement logic. We also expect the relationship between participant diversity and reviewers’ ratings to be moderated by project novelty and fuzziness of technology category. We find support for our hypotheses with a sample of collaborative innovation projects funded by the Advanced Technology Program of the U.S. National Institute of Standards and Technology.  相似文献   
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