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61.
Although prior research conceptualizes how knowledge-seeking motivates the internationalization of emerging-market enterprises (EMEs), whether outward foreign direct investment (OFDI) indeed leads to enhanced innovation performance has received limited attention. We address this subject by conceptualizing how Chinese EMEs’ OFDI enhances their subsidiaries’ organizational learning and innovation performance and whether geographic location choices influence this relationship. Our panel data analysis of Chinese EMEs shows that OFDI has a positive effect on innovation performance of Chinese EMEs’ subsidiaries and that this effect is stronger when the OFDI is directed towards developed rather than emerging countries. These findings advance the notion that EMEs can use OFDI as a strategy to globalize R&D and enhance their innovation performance and demonstrate that certain established assumptions regarding organizational learning are not valid for EMEs. 相似文献
62.
Makras P Koukoulis GN Bourikas G Papatheodorou G Bedevis K Menounos P Pappas D Kartalis G 《Journal of sports sciences》2005,23(8):825-834
In this study, we assessed the effects of a 4 week basic military physical training programme for male recruits of the Hellenic Air Force on the number and distribution of circulating immune cells and adrenergic and adrenocortical hormonal responses. One group of recruits (exercised, n = 48) participated in moderate intermittent physical exercise, whereas a second group (non-exercised controls, n = 9) performed only light work in the barracks. Both groups participated in the same non-physical, classroom-type training and testing. Military training by the exercised group resulted in significant increases in CD4+ T-lymphocytes, renal cortisol excretion and the urinary noradrenaline/adrenaline ratio, together with reductions in neutrophils and the neutrophil/lymphocyte ratio. In the exercised group, the urinary noradrenaline/adrenaline ratio correlated positively with the training-induced changes in CD4+ T-lymphocytes and negatively with changes in the neutrophil/lymphocyte ratio. No significant relationship was found between training-induced increases in cortisol excretion and any of the peripheral blood cell alterations. Our results indicate that 4 weeks of military training consisting of intermittent moderate exercise resulted in a significant increase in CD4+ T-lymphocytes and reduction in neutrophils. These changes were probably driven by alterations in hormonal status, including the significant impact of sympathetic nervous system activation. 相似文献
63.
A Memory-Based Approach to Anti-Spam Filtering for Mailing Lists 总被引：14，自引：0，他引：14
Georgios Sakkis Ion Androutsopoulos Georgios Paliouras Vangelis Karkaletsis Constantine D. Spyropoulos Panagiotis Stamatopoulos 《Information Retrieval》2003,6(1):49-73
This paper presents an extensive empirical evaluation of memory-based learning in the context of anti-spam filtering, a novel cost-sensitive application of text categorization that attempts to identify automatically unsolicited commercial messages that flood mailboxes. Focusing on anti-spam filtering for mailing lists, a thorough investigation of the effectiveness of a memory-based anti-spam filter is performed using a publicly available corpus. The investigation includes different attribute and distance-weighting schemes, and studies on the effect of the neighborhood size, the size of the attribute set, and the size of the training corpus. Three different cost scenarios are identified, and suitable cost-sensitive evaluation functions are employed. We conclude that memory-based anti-spam filtering for mailing lists is practically feasible, especially when combined with additional safety nets. Compared to a previously tested Naive Bayes filter, the memory-based filter performs on average better, particularly when the misclassification cost for non-spam messages is high. 相似文献
64.
Vassilios Gourgoulis Alexia Boli Nikolaos Aggeloussis Argyris Toubekis Panagiotis Antoniou Panagiotis Kasimatis 《Journal of sports sciences》2013,31(3):278-289
AbstractThe aim of this study was to examine the influence of leg kick on the pattern, the orientation and the propulsive forces produced by the hand, the efficiency of the arm stroke, the trunk inclination, the inter-arm coordination and the intra-cyclic horizontal velocity variation of the hip in sprint front crawl swimming. Nine female swimmers swam two maximal trials of 25 m front crawl, with and without leg kick. Four camcorders were used to record the underwater movements. Using the legs, the mean swimming velocity increased significantly. On the contrary, the velocity and the orientation of the hand, the magnitude and the direction of the propulsive forces, as well as the Froude efficiency of the arm stroke were not modified. The hip intra-cyclic horizontal velocity variation was also not changed, while the index of coordination decreased significantly. A significant decrease (13%) was also observed in the inclination of the trunk. Thus, the positive effect of leg kick on the swimming speed, besides the obvious direct generation of propulsive forces from the legs, could probably be attributed to the reduction of the body’s inclination, while the generation of the propulsive forces and the efficiency of the arm stroke seem not to be significantly affected. 相似文献
65.
Maria Kordaki Marina Papastergiou Panagiotis Psomos 《Education and Information Technologies》2016,21(4):837-862
The aim of this work was twofold. First, an empirical study was designed aimed at investigating the perceptions that entry-level non-computing majors -namely Physical Education and Sport Science (PESS) undergraduate students- hold about basic Computer Literacy (CL) issues. The participants were 90 first-year PESS students, and their perceptions were elicited through a written questionnaire. The data analysis revealed scientifically acceptable perceptions as well as various empirical, vague, incomplete and erroneous perceptions. Second, those students’ prior knowledge was utilized to design and implement an Educational Computer Card Game (ECCG) aimed at helping PESS students overcome their conceptual difficulties and approach the aforementioned CL issues in a scientifically consistent manner. The ECCG was designed taking into account basic digital game-based learning principles in combination with basic aspects of social and constructivist perspectives to learning. The ECCG was also pilot-tested in the field with real students, and the results were encouraging. 相似文献
66.
We present criteria for the analysis and elaboration of the content of instruction, at middle school level, in a specific domain: physics. This content, which we call the knowledge to be taught, has to respect several constraints in order to be teachable in a real school. Here we have chosen to analyse in depth those constraints which are related to the specific features of the physics. One of the constraints is a goal which, very often, justifies physics teaching: the operational aspect of physics knowledge in everyday life. The other constraint is related to a crucial aspect of an experimental science: the need for coherence between the formal aspects and their field of applicability. Our analysis is based on an epistemological approach to physics knowledge and on assumptions about learning. This analysis is related to the case of an innovative programme of teaching on electricity.This article was accepted during the editorship of Paul Lefrere. 相似文献
67.
Marina Palla Despina Potari Panagiotis Spyrou 《International Journal of Science and Mathematics Education》2012,10(5):1023-1045
In this study, we investigate the meaning students attribute to the structure of mathematical induction (MI) and the process of proof construction using mathematical induction in the context of a geometric recursion problem. Two hundred and thirteen 17-year-old students of an upper secondary school in Greece participated in the study. Students’ responses in 3 written tasks and the interviews with 18 of them are analyzed. Though MI is treated operationally in school, the students, when challenged, started to recognize the structural characteristics of MI. In the case of proof construction, we identified 2 types of transition from argumentation to proof, interwoven in the structure of the geometrical pattern. In the first type, MI was applied to the algebraic statement that derived from the direct translation of the geometrical situation. In the second type, MI was embedded functionally in the geometrical structure of the pattern. 相似文献
68.
James D. Pickering Antoniou Panagiotis Georgios Ntakakis Alkinoos Athanassiou Emmanouil Babatsikos Panagiotis D. Bamidis 《Anatomical sciences education》2022,15(3):628-635
Augmented, mixed, and virtual reality applications and content have surged into the higher education arena, thereby allowing institutions to engage in research and development projects to better understand their efficacy within curricula. However, despite the increasing interest, there remains a lack of robust empirical evidence to justify the mainstream acceptance of this approach as an effective and efficient learning tool. In this study, the impact of a mixed reality application focused on long spinal cord sensory and motor pathways is explored in comparison to an existing resource already embedded within an active curriculum (e.g., anatomy drawing screencasts). To assess the changes in learner gain, a quasi-randomized control trial with a pre- and post-test methodology was used on a cohort of Year 2 medical students, with both the absolute and normalized gain calculated. Similar patterns of learner gain were observed between the two groups; only the multiple-choice questionnaires were shown to be answered significantly higher with the screencast group. This study adds important empirical data to the emerging field of immersive technologies and the specific impact on short-term knowledge gain for neuroanatomy teaching, specifically that of long sensory and motor pathways. Despite the limitations of the study, it provides important additional data to the field and intends to support colleagues across the education landscape in making evidence-informed decisions about the value of including such resources into their curricula. 相似文献