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71.
Innovators and imitators: Organizational reference groups and adoption of organizational routines 总被引:3,自引:0,他引:3
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
72.
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
73.
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
74.
Students in their first year of university face a number of transition issues that can make realising their academic potential difficult. In the sciences, first-year courses cover a large amount of material across broad subject areas, which can make them troublesome for students without background knowledge, and students need to adapt to typically large class sizes and develop active, independent learning skills. We expected a student's prior learning to be important to their academic performance in a large, first-year introductory biology subject and analysed the relationships between students' results in this course with their senior high school results in related subjects over three years from 2007 to 2009. We predicted that students with prior learning in biology would have higher results than those without it, but that chemistry might also be important, given the biochemical nature of much of the course content. Students who completed biology at the senior high school-level did perform better than those who had not, but only if they also completed chemistry. Prior learning in biology was of no benefit to students in first-year biology, except when combined with chemistry, suggesting that potential differences in biology curricula between high school and the first year at university may need to be addressed. 相似文献
75.
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
76.
This paper considers the simultaneous stabilization of a set of nonlinear systems, that involve uncertain nonlinearities besides multiple time-varying delays in the states. Under the assumption that the upper bounds of delays are known, a memoryless simultaneously stabilizing state feedback controller is presented by proposing a control Lyapunov-Krasovskii functional (CL-KF) method. As required to establish the CL-KF approach, a systematic procedure is given to construct CL-KFs for the systems under consideration. By the obtained CL-KFs, a common stabilizing state feedback control law is established to drive all the systems to the origin. Examples are finally given to verify the benefit of the proposed design method. 相似文献
77.
78.
Gergely Simon Caroline Busch Marco A. B. Andrade Julien Reboud Jonathan M. Cooper Marc P. Y. Desmulliez Mathis O. Riehle Anne L. Bernassau 《Biomicrofluidics》2021,15(1)
Separation and sorting of biological entities (viruses, bacteria, and cells) is a critical step in any microfluidic lab-on-a-chip device. Acoustofluidics platforms have demonstrated their ability to use physical characteristics of cells to perform label-free separation. Bandpass-type sorting methods of medium-sized entities from a mixture have been presented using acoustic techniques; however, they require multiple transducers, lack support for various target populations, can be sensitive to flow variations, or have not been verified for continuous flow sorting of biological cells. To our knowledge, this paper presents the first acoustic bandpass method that overcomes all these limitations and presents an inherently reconfigurable technique with a single transducer pair for stable continuous flow sorting of blood cells. The sorting method is first demonstrated for polystyrene particles of sizes 6, 10, and 14.5 μm in diameter with measured purity and efficiency coefficients above 75 ± 6% and 85 ± 9%, respectively. The sorting strategy was further validated in the separation of red blood cells from white blood cells and 1 μm polystyrene particles with 78 ± 8% efficiency and 74 ± 6% purity, respectively, at a flow rate of at least 1 μl/min, enabling to process finger prick blood samples within minutes. 相似文献
79.
V. B. Saputra S. K. Ong A. Y. C. Nee 《上海大学学报(英文版)》2014,(3):222-230
This paper presents a calibration method for parallel manipulators using a measurement system specially installed on an external fixed frame. The external fixed frame is important as an error reference for calibration in certain operations, such as in the configuration of a parallel manip- ulator functioning as a machine tool where the workpiece is fixed to a worktable. The pose of the end-effector is mea- sured using three digital indicators installed on the external fixed frame. To enable measurement, the end-effector is assumed to be a plane large enough that all digital indicators could touch. The error is defined as the difference between the theoretical and actual readings of the digital indicators. The geometric parameters of the parallel manipulator are optimized to minimize this error. This calibration method is low cost and feasible for compensating geometric parameter errors for a parallel manipulator. Optimal pose selection for the calibration is achieved using a swarm intelligence search algorithm. The method is implemented on a prototype of a six degrees-of-freedom (DOFs) Gough-Stewart platform constructed to function as a machine tool. 相似文献
80.
Ng Peggy M. L. Chan Jason K. Y. Lit Kam Kong 《Education and Information Technologies》2022,27(6):8129-8145
Education and Information Technologies - Online collaborative learning (OCL) has received significant attention, but the ultimate goal of adopting OCL is neglected, especially in higher education... 相似文献