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To investigate whether spatial assimilation effects are due to premovement control processes or postinitiation feedback processes, surface EMG recordings were made from two agonists and one antagonist during both single and dual movements involving the upper limb(s). In the single condition, subjects (N = 7) made 25 Short (20 degrees) and 25 Long (60 degrees) reversal movements using levers in the sagittal plane, in 195 ms to reversal. In the dual condition, both Short and Long movements were performed simultaneously for 75 trials, the last 25 of which were without knowledge of results. Subjects overshot the Short target in the dual condition, showing spatial assimilation effects. Overshooting was associated with increased peak EMG in the initial (premovement) agonist burst, supporting the notion that spatial assimilation effects are modulated via premovement control processes. 相似文献
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A simple iterative technique, which is free of certain shortcomings of the previous methods, is proposed for the approximation of large linear systems by a lower- order model. Here, the measure of the goodness of the approximate model is taken to be the value of the integral-square error between the step responses of the exact and the simplified systems. The proposed technique consists of a two-step iterative scheme. In the first step, the optimum residues are obtained by the minimization of the objective function, while the poles (or eigenvalues) are kept constant. In the second step, the poles are optimized while the residues remain fixed. This procedure is continued cyclically until the objective function is satisfactorily minimized. The necessary and sufficient conditions for existence of an optimum are satisfied in each step. The residues, poles and objective functions converge monotonically. The resulting reduced-order model obtained by this method is stable if the original system is stable. The method can also be applied to systems with repeated poles and to multivariable systems. The results are superior to those obtained previously in the steady-state, the point-by-point transient response, and the value of the integral-square error. Illustrative examples are presented. 相似文献
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The purpose of this study was to explore what salient characteristics can be found in some university teachers＇ approaches to teaching in Finland, Japan and India, and in what ways university teachers in Finland, India and Japan use ICTs （information and communication technologies） in their own teaching. Furthermore, this study aimed to investigate what ICT applications these same teachers use in their teaching. The data were collected via an electronic survey and interviews. The participants （N=21） were university teachers from Finland （N=8）, Japan （N=I0） and India （N=3）. Their approaches to teaching were explored by applying the ATI （approaches to teaching inventory） and its modified version focusing on the use of ICTs in teaching. The study reported in this paper was a pilot study, thus the results are based on the limited number of respondents. The ATI and ATI ICT subscales and ICT inventory applied in this study have been confirmed to be valid. The university teachers in Japan and Finland differed in their approaches to teaching： The Finnish teachers scored higher on the CCSF （conceptual change orientated, student-focused） approach to teaching than the Japanese teachers, while the Japanese teachers scored higher on the ITTF （information transmitting, teacher-focused） approach to teaching. Two Indian teachers were classified as having a teacher-focused approach to teaching, while the third was classified as having a student-focused approach to teaching. The teachers＇ differences in their use of ICTs related more to their disciplinary status than to their cultural background. 相似文献
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A two-step iterative method (1,2) for a reduction in the order of linear continuous-time systems, given in the state equation or the transfer function, is extended to reduce discrete-time systems. The method requires the optimization of the residues and eigenvalues (or poles) belonging to an objective function. The objective function to be minimized is chosen as the finite sum of the squares of the error between the step responses of the reduced model and the original system. This scheme is continued cyclically until the objective function is satisfactorily minimized. By investigating the initial selection of the eigenvalues in the reduced-order model, it is found that the dominant eigenvalues of the original system give a good approximation. Further, the resulting model is always stable, assuming the original system is stable. As shown in a numerical example, the proposed method is superior to the other methods of model reduction in both steady-state and transient responses, and in the value of the sum of the squares of the error. 相似文献
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Mikiko Nishimura Takashi Yamano Yuichi Sasaoka 《International Journal of Educational Development》2008
While some governments in Sub-Saharan Africa have abolished tuition to achieve universal primary education (UPE), few studies have examined the impacts of the UPE policy beyond school enrolment. This study estimates the impact of the UPE policy in Uganda on overall primary education attainments by using data including 940 rural households. We find that UPE has decreased delayed enrolments and increased grade completion rates up to the fifth grade and its effects are especially large among girls in poor households. Yet, schools in Uganda still face further challenges in terms of low internal efficiency and the unequal quality of education. 相似文献
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Megan N. Shoji Anna R. Haskins David E. Rangel Kia N. Sorensen 《Early childhood research quarterly》2014
Scholars suggest that racial/ethnic and class disparities in school-based social capital contribute to educational inequalities. Previous studies demonstrate that social capital (relations of trust, mutual expectations, and shared values) between parents and schools supports children's development. Yet we know little about the emergence of social capital, that is, the processes through which it develops. In this study, we explore mechanisms of social capital emergence in predominantly low-income Latino school communities. We draw data from an experimental study that manipulated social capital through an after-school family engagement program. Based on interviews and focus groups with participating parents, teachers, and program staff in two elementary schools, we identified four types of interactions that act as mechanisms of social capital emergence: (1) responsive communication; (2) reciprocal communication; (3) shared experiences; and (4) institutional linkage. The article connects these mechanisms to theoretically linked sources of social capital and discusses implications for theory and practice. 相似文献
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Mikiko Nishimura 《Asia Pacific Education Review》2006,7(2):205-217
It is widely acknowledged that the private costs of education occupy a substantial part of the overall education cost and
thus they have implications for quality and equity in education. The case of Japan demonstrates that access to basic education
at junior high school level is unequal and inequitable when considering private costs of education borne within and outside
the school system. It was also found that household spending on supplementary education in public schools is likely to be
determined by local implementation of education reforms. Current education reform with its absence of financial and technical
support to schools under the guise of deregulation does not seem to generate good levels of choice nor does it seem to sustain
quality and equity in education. 相似文献
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The Free Primary Education (FPE) policy in Kenya created a dichotomy between the widespread notion that the government should be responsible for everything and the reality that the government had stopped recruiting teachers. This article investigates the current state of the accountability system for school governance in public schools in the Maasai community in Loitokitok District, Kajiado County, by focusing on the client power of parents and communities. A case study of eight schools in the Masai community reveals that a sense of “working together” and a substantial degree of client power are present in various school initiatives. Elements that enhance client power include information sharing, collaboration and coordination with stakeholders, critical-thinking ability, respect and trust, and other unique efforts. The study also indicates the limitations of the dichotomous lens of “service provider” and “client” and questions the instrumental approach to community participation in school management.
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