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71.
全链条创新经历基础研究到最终产业化,周期长,涉及核心关键技术多,是国家实现创新驱动发展的重要路径之一。但是要实现全链条周期的穿越,以及从学术界到产业界的跨越,涉及科技、市场、评价、人才等众多要素,是一个复杂和充满挑战的过程,锂离子电池技术的研究以及产业化就是一个典型的例子。中国科学院物理研究所在过去40余年中,围绕锂离子电池领域进行了很多有益的探索,对全链条创新所需的生态和条件积累了一些初步认识。文章通过对该过程的梳理与分析,对新时期科研机构探索践行创新驱动发展战略提供可供借鉴的经验。  相似文献   
72.
Exact solutions, based on couple-stresses plane strain theory of elasticity, are presented for the normal, shear and couple-stresses, displacements and rotations of an infinite-length (in z-axis) rectangular thin plate simply supported at two opposite edges (i.e.xL) and bent by a uniform load. Exact solutions reduce to classical values as l→0. Here l is defined as the new elastic material constant taking account of couple stresses.  相似文献   
73.
74.
Information Economy and Changing Occupational Structure in Singapore   总被引:1,自引:0,他引:1  
Using population census data since 1921, this article traces changes in employment and occupational structure in Singapore in the past 80 years. This is a follow-up to an earlier paper by Kuo and Chen (1987) that reported the nascent formation of the information society in Singapore till the 1980s. It also makes an assessment of the role of proactive government policies in directing industrial restructuring and occupational changes in this city-state. It is found that the long-term growing trend in information-related occupations has been in tandem and supportive of industrial changes in Singapore. One more wave of growth of information producers (and certainly, innovators) and information distributors is expected in the next couple of decades. The momentum has started, and competition from regional countries similarly aspiring to be information and knowledge economies will quicken the pace. The government has initiated fundamental changes in the educational system to meet the challenges of the knowledge-based economy. The small city-state has also long adopted an adaptive philosophy to be responsive to the ever-changing environment, either in technology or in regional politics. Based on the trend analysis, it is expected that the emergent information society will graduate into full status when Singapore attains a developed country status in the forthcoming decades.  相似文献   
75.
Firms vary greatly in their rates of creating and adopting technological and organizational innovations, in part because of their choice of reference group. We argue that the selection of a reference group is a crucial and neglected source of firm heterogeneity. Comparisons to the average of other firms in a population cause most firms to adopt innovations once they are widely accepted. A distinctive feature of the minority of innovating firms that create innovations or adopt them early is that they compare themselves with, compete with, and try to differ from other innovating firms, whereas the majority of firms compare themselves with, and conform to, a broader group of firms. We elaborate this argument based on the behavioral theory of the firm and institutional theory, and test it on a two-period survey on adoptions of innovative organizational forms in Europe and the US. The analysis shows the predicted differences in the adoption patterns of innovating and imitating firms.  相似文献   
76.
Synchronous data transmission systems that transmit information over dispersive channels often employ adaptive equalization techniques in the processing of the received signals. Most equalizers presently used in communication systems are of the tapped delay line (TDL) type. In this paper, we propose a class of adaptive equalizers of which the TDL equalizer is a member. Another interesting member of this class is the Laguerre adaptive equalizer which is to be introduced in this paper. The configuration of the Laguerre equalizer is developed. It is found, as shown by the examples, that the Laguerre equalizer is more accurate, and is less sensitive to timing error than the conventional TDL equalizer.  相似文献   
77.
This article draws on a notion of the hospital as a complex service provider and healthcare system hub in order to examine the question of innovation in hospitals. It puts forward a relatively simple framework for analysing hospital output, in which the medical function is incorporated into a complex system of other constituent services that make use of different types of technologies. This analytical framework is used to reveal the multiple sources of innovation and the main organising principles driving innovation within hospitals.  相似文献   
78.
In this paper, the problem of estimating the parameters of a two-dimensional autoregressive moving-average (2-D ARMA) model driven by an unobservable input noise is addressed. In order to solve this problem, the relation between the parameters of a 2-D ARMA model and their 2-D equivalent autoregressive (EAR) model parameters is investigated. Based on this relation, a new algorithm is proposed for determining the 2-D ARMA model parameters from the coefficients of the 2-D EAR model. This algorithm is a three-step approach. In the first step, the parameters of the 2-D EAR model that is approximately equivalent to the 2-D ARMA model are estimated by applying 2-D modified Yule-Walker (MYW) equation to the process under consideration. Then, the moving-average parameters of the 2-D ARMA model are obtained solving the linear equation set constituted by using the EAR coefficients acquired in the first step. Finally, the autoregressive parameters of the 2-D ARMA model are found by exploiting the values obtained in first and second steps. The performance of the proposed algorithm is compared with other 2-D ARMA parameter and spectral estimation algorithms available in the technical literature by means of three different criteria. As a result of this comparison, it is shown that the parameters and the corresponding power spectrums estimated by using the proposed algorithm are converged to the original parameters and the original power spectrums, respectively.  相似文献   
79.
In this paper, an algorithm is developed to apply Hann, Hamming, Blackman and related windows directly in the transform domain for the discrete cosine transform and discrete sine transform. These algorithms are useful in applications where windowing is required in order to minimize edge effects caused by implicit symmetries in the transform domain that are not replicated in the real-world data. Examples of such applications include data communication, adaptive system identification and filtering, real-time analysis of financial market data, etc. Software implementations in C language are also given.  相似文献   
80.
The purpose of this study was to develop a poststructural feminist pedagogical model and to investigate whether vocational-and-technical college students receiving poststructural feminist instruction would exhibit better learning achievement and critical thinking ability, and express greater satisfaction with their classes than those receiving traditional instruction. In applying a poststructural feminist model, the researchers intended to help both the teacher and students work together to overcome the estrangement and alienation that have long been the norm in the contemporary Chinese education system. The research results show that the poststructural feminist pedagogy had a positive effect upon the participants in the experimental group. Several conclusions are elicited from the study. First, in the English language achievement post-test, the participants receiving the poststructural feminist instruction significantly outperformed those receiving the traditional banking instruction in terms of listening, vocabulary, grammar, and reading. Second, in the critical thinking ability post-test, the participants significantly outperformed those receiving the traditional banking instruction in terms of length, focus, content, organization, and style. Third, in regard to the students’ satisfaction, it was clearly shown that the students who received the instruction informed by poststructural feminist pedagogy expressed significantly greater satisfaction than those who had received traditional banking instruction in terms of instructional objective, teaching method/materials, teacher quality, class environment, and assessment.  相似文献   
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