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21.
This study reviews empirical data from the U.S. Census, American Community Survey (ACS) and academic journals to explore K-12 and higher educational outcomes pertaining to Southeast Asian American (SEAA) males. We argue that the empirical dismissal of SEAA males in social science research reinforces a longstanding agenda of structural neglect and invisibility. By disaggregating some of the existing data for Cambodian, Hmong, Laotian, and Vietnamese subgroups from the broader “Asian” group, we hope to repudiate the model minority myth and stereotypes related to masculinity. Findings revealed that SEAA males had K-12 and higher educational outcomes that contradict the standard conception of academic and financial success. We situate the findings of the article in a discussion of intersectionality and the mainstream cultural forces that impact SEAA males. 相似文献
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It is well known that sliding mode control is based on the definition of an invariant manifold, where the system dynamics are forced to in a finite time. Such a manifold is somewhat arbitrarily defined, as long as the system dynamics are stable on it. Computational and control effort may vary depending on selected manifold. Obviously, if a system has naturally acceptable stable dynamics around a desired equilibrium point, no control is needed unless uncertainties or disturbances are present. It would be desirable that if such a system had uncertainties or disturbances, the control effort be designed only to overcome the effect of such factors. For a system with first order dynamics and affine control input, designing a sliding mode control overcoming only such uncertainties or disturbances is a trivial task. When a higher order dynamics system is involved, unit control may be used, where the input control signals are not discontinuous, but when only discontinuous control inputs are available, a design approach is not readily available. In this paper, taking advantage of the natural stable dynamics of a system, a sliding mode control approach is introduced for designing multiple discontinuous control inputs, where the control effort overcomes only uncertainties, disturbances or unstable dynamics. Two illustrative examples are given in order to show the feasibility of the method. 相似文献
24.
International knowledge spillovers, especially through multinational companies (MNCs), have recently been a major topic of academic and management debate. However, most studies treat MNC subsidiaries as relatively passive actors. We challenge this assumption by investigating the drivers of knowledge protection intensity of MNC subsidiaries. We argue that knowledge protection intensity is determined by MNC subsidiary mandates and by opportunities and risks originating from the host region. We hypothesize that not just competence-creating but also competence-exploiting mandates increase knowledge protection intensity. In addition, technological cluster regions in the host country can be expected to provide opportunities for knowledge sourcing and MNC subsidiaries may be willing to protect knowledge less intensively to participate in cluster networks. We test our hypotheses using a dataset of 694 observations of 631 MNC subsidiaries in Germany and develop recommendations for research, managers and policy makers. 相似文献
25.
Costa Ricardo V Fernández-Jardon Fernández Carlos Figueroa Dorrego Pedro 《知识管理研究与实践》2014,12(3):322-338
Knowledge Management Research & Practice - The general purpose of this research is to study interaction effects between intangible assets and product innovation. More specifically, the authors... 相似文献
26.
Javier Noya Salces Pedro M. Gómez-Carmona Diego Moliner-Urdiales Manuel Sillero-Quintana 《Journal of sports sciences》2014,32(13):1263-1270
AbstractThe aim was to examine the injuries sustained by Spanish football players in the First Division and to compare injury-related variables in the context of both competition and training. The injury data were prospectively collected from 16 teams (427 players) using a specific web-based survey during the 2008/2009 season. A total of 1293 injuries were identified (145 were recurring injuries). The overall injury incidence was 5.65 injuries per 1000 h of exposure. Injuries were much more common during competition than during training (43.53 vs. 3.55 injuries per 1000 h of exposure, P < 0.05). Most of the injuries (89.6%) involved the lower extremities, and overuse (65.7%) was the main cause. Muscle and tendon injuries were the most common types of injury (53.8%) among the players. The incidence of training injuries was greater during the pre-season and tended to decrease throughout the season, while the incidence of competition injuries increased throughout the season (all P < 0.05). In conclusion, the results of this study suggest the need for injury prevention protocols in the First Division of the Spanish Football League to reduce the number of overuse injuries in the muscles and tendons in the lower extremities. In addition, special attention should be paid during the pre-season and the competitive phase II (the last four months of the season) in order to prevent training and competition injuries, respectively. 相似文献
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The COVID-19 pandemic,still raging worldwide,imposes staggering human and economic costs.These will only increase as many convalescent patients suffer consequen... 相似文献
28.
Pedro Rosário Julia Högemann José Carlos Núñez Guillermo Vallejo Jennifer Cunha Vera Oliveira Sonia Fuentes Celestino Rodrigues 《Reading and writing》2017,30(5):1009-1032
Students’ writing problems are a global educational concern and is in need of particular attention. This study aims to examine the impact of providing extra writing opportunities (i.e., writing journals) on the quality of writing compositions. A longitudinal cluster-randomized controlled design using a multilevel modeling analysis with 182 fourth grade students was conducted. We examined whether students’ writing quality differed when writing journals on a weekly basis for 12 weeks, compared with a control group. Three covariates were analyzed, namely: (i) the students’ attitudes towards writing; (ii) their self-efficacy in writing; (iii) and their use of self-regulation (SRL) strategies while writing. Findings have shown that students who wrote week-journals significantly improved the writing quality of their compositions and reported a higher use of SRL strategies in writing. Nevertheless, self-efficacy and attitude towards writing were found to not be related to the quality of the compositions. Moreover, data indicated that the writing quality of compositions improved along with the writing quality of the week-journals. Findings suggest the use of week-journals in class to promote writing. 相似文献
29.
This paper is aimed to investigate the operating characteristics of a static synchronous compensator (STATCOM) integrated with superconducting magnetic energy storage (SMES) for high power applications in the transmission network level. The STATCOM controller topology comprises multi-level multi-pulse neutral-point clamped-type (NPC) voltage source inverters (VSIs) using the harmonics cancellation technique, and incorporates a SMES coil. An innovative two-quadrant multi-level dc-dc converter is proposed to effectively interface the STATCOM with the superconducting coil using a buck-boost topology with neutral point voltage control capabilities; thus enabling to simultaneously control both active and reactive power exchange with the high voltage power system. A detailed analysis of major system variables is presented, including analytical results and digital simulations using the MATLAB/Simulink environment. Moreover, a three-level control scheme is designed, including a full decoupled current control strategy in the d-q reference frame with a novel controller to prevent the STATCOM dc bus capacitors voltage drift/imbalance and an enhanced power system frequency controller. 相似文献
30.