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121.
Companies use many different marketing strategies in order to make their products known and place their corporate images and brandings in the market. Besides, nowadays, being on the Intemet is a must for every company striving for success. The development and implementation of Web 2.0 or social web are threatening the basis of the ways of mixing with other people. A company devoted to open and distance learning, such as Master-D Corporation, a clear example of how a proper and planned use of the different possibilities offered by the Web 2.0, based on blogs, allows a company to achieve bigger market shares and brand positioning following the win-win principle. Blogs are, undoubtedly, channels of communication that prove the power of attraction of good information. These changes are affecting everybody and, in particular, companies and institutions related to people's education, teaching and training for their inclusion in society and labor market. This essay brings up some reflections in two ways: The first one deals with some reasons why education is also related to the concept of "company"; and the second one deals with how these changes generated by Web 2.0 are affecting some training companies, represented in this case by Master-D, 相似文献
122.
Sarasola Ane Rojas Jose Félix Okariz Ana 《Journal of Science Education and Technology》2015,24(5):595-609
Journal of Science Education and Technology - In this work, a specific implementation of a so-called experimental or open-ended laboratory is proposed and evaluated. Keeping in mind the scheduling... 相似文献
123.
The development of widely applicable point-of-care sensing and diagnostic devices can benefit from simple and inexpensive fabrication techniques that expedite the design, testing, and implementation of lab-on-a-chip devices. In particular, electrodes integrated within microfluidic devices enable the use of electrochemical techniques for the label-free detection of relevant analytes. This work presents a novel, simple, and cost-effective bench-top approach for the integration of high surface area three-dimensional structured electrodes fabricated on polystyrene (PS) within poly(dimethylsiloxane) (PDMS)-based microfluidics. Optimization of PS-PDMS bonding results in integrated devices that perform well under pressure and fluidic flow stress. Furthermore, the fabrication and bonding processes are shown to have no effect on sensing electrode performance. Finally, the on-chip sensing capabilities of a three-electrode electrochemical cell are demonstrated with a model redox compound, where the high surface area structured electrodes exhibit ultra-high sensitivity. We propose that the developed approach can significantly expedite and reduce the cost of fabrication of sensing devices where arrays of functionalized electrodes can be used for point-of-care analysis and diagnostics. 相似文献
124.
Robert Jenssen Jose C. Principe Torbjørn Eltoft 《Journal of The Franklin Institute》2006,343(6):614-629
This paper contributes a tutorial level discussion of some interesting properties of the recent Cauchy-Schwarz (CS) divergence measure between probability density functions. This measure brings together elements from several different machine learning fields, namely information theory, graph theory and Mercer kernel and spectral theory. These connections are revealed when estimating the CS divergence non-parametrically using the Parzen window technique for density estimation. An important consequence of these connections is that they enhance our understanding of the different machine learning schemes relative to each other. 相似文献
125.
Searchers can face problems finding the information they seek. One reason for this is that they may have difficulty devising queries to express their information needs. In this article, we describe an approach that uses unobtrusive monitoring of interaction to proactively support searchers. The approach chooses terms to better represent information needs by monitoring searcher interaction with different representations of top-ranked documents. Information needs are dynamic and can change as a searcher views information. The approach we propose gathers evidence on potential changes in these needs and uses this evidence to choose new retrieval strategies. We present an evaluation of how well our technique estimates information needs, how well it estimates changes in these needs and the appropriateness of the interface support it offers. The results are presented and the avenues for future research identified. 相似文献
126.
Ton de Jong Ernesto Martin Jose‐Miguel Zamarro Francisco Esquembre Janine Swaak Wouter R. van Joolingen 《科学教学研究杂志》1999,36(5):597-615
Discovery learning is generally seen as a promising but demanding mode of learning that, in most cases, can only be successful if students are guided in the discovery process. The present article discusses a study on discovery learning with a computer simulation environment in the physics domain of collisions. In the learning environment, which is called Collision, students learned about collisions where two particles move in the same direction and interact via a conservative force in such a way that the total mechanical energy is conserved. In the experiment we conducted with Collision, we evaluated the effects of adding two different ways to guide students: model progression, in which the model is presented in separate parts; and assignments, small exercises that the student can choose to do. The effect of providing assignments and model progression was evaluated by comparing the learning behavior and learning results over three experimental conditions in which different versions of the simulation environment were presented: pure simulation, simulation plus assignments, and simulation plus model progression and assignments. Students' use of the environment was logged, their subjectively experienced workload was measured on‐line, and their learning was assessed using a number of assessment procedures. Providing assignments with the simulation improved students' performance on one aspect of a so‐called intuitive knowledge test. Providing the students with model progression did not have an effect. A subjective workload measure indicated that expanding the simulation with assignments and model progression did not raise the workload experienced by the students. © 1999 John Wiley & Sons, Inc. J Res Sci Teach 36: 597–615, 1999 相似文献
127.
Fernando Ornelas Tellez Alexander G. Loukianov Eduardo Jose Bayro Corrochano 《Journal of The Franklin Institute》2010,347(6):1015-1034
This paper presents a discrete-time decentralized neural identification and control for large-scale uncertain nonlinear systems, which is developed using recurrent high order neural networks (RHONN); the neural network learning algorithm uses an extended Kalman filter (EKF). The discrete-time control law proposed is based on block control and sliding mode techniques. The control algorithm is first simulated, and then implemented in real time for a two degree of freedom (DOF) planar robot. 相似文献
128.
Carlos Cristi-Montero Javier Courel-Ibez Francisco B. Ortega Jose Castro-Piero Alba Santaliestra-Pasias Angela Polito Jrmy Vanhelst Ascensin Marcos Luis M. Moreno Jonatan R. Ruiz HELENA study group 《运动与健康科学(英文)》2021,10(3):360-367
PurposeThis study was aimed to analyze the mediation role of cardiorespiratory fitness (CRF) on the association between fatness and cardiometabolic risk scores (CMRs) in European adolescents.MethodsA cross-sectional study was conducted in adolescents (n = 525; 46% boys; 14.1 ± 1.1 years old, mean ± SD) from 10 European cities involved in the Healthy Lifestyle in Europe by Nutrition in Adolescence study. CRF was measured by means of the shuttle run test, while fatness measures included body mass index (BMI), waist to height ratio, and fat mass index estimated from skinfold thicknesses. A clustered CMRs was computed by summing the standardized values of homeostasis model assessment, systolic blood pressure, triglycerides, total cholesterol/high-density lipoprotein cholesterol ratio, and leptin.ResultsLinear regression models indicated that CRF acted as an important and partial mediator in the association between fatness and CMRs in 12–17-year-old adolescents (for BMI: coefficients of the indirect role β = 0.058 (95% confidence interval (95%CI): 0.023–0.101), Sobel test z = 3.11 (10.0% mediation); for waist to height ratio: β = 4.279 (95%CI: 2.242–7.059), z =3.86 (11.5% mediation); and for fat mass index: β = 0.060 (95%CI: 0.020–0.106), z = 2.85 (9.4% mediation); all p < 0.01).ConclusionIn adolescents, the association between fatness and CMRs could be partially decreased with improvements to fitness levels; therefore, CRF contribution both in the clinical field and public health could be important to consider and promote in adolescents independently of their fatness levels. 相似文献
129.
130.
Alberto Grao-Cruces David Sánchez-Oliva Carmen Padilla-Moledo Rocío Izquierdo-Gómez Verónica Cabanas-Sánchez Jose Castro-Piñero 《Journal of sports sciences》2020,38(7):780-786
ABSTRACTThe aims of this study were (i) to examine the sedentary time (ST) during different time periods [i.e., weekend, out-of-school weekdays hours, school hours, recess, physical education classes (PEC)] in children and adolescents; (ii) to identify 2-year longitudinal changes in the ST for these periods; and (iii) to examine if ST at baseline is associated with ST 2 years later. This was a 2-year follow-up study with 826 (51.9% boys) children and 678 (50.7% boys) adolescents. Accelerometers were used to assess ST. Students spent more than 60% of their weekend, out-of-school hours and school hours in ST. During these periods, girls and adolescents were more sedentary than boys and children, respectively (p < 0.05). Over 2-year follow-up, ST increased during the weekend, out-of-school hours, school hours and recess in all subgroups studied (p < 0.001). ST during PEC declined 2% per year in children (p < 0.001) but it increased in adolescents (p < 0.05). ST during the periods analysed at baseline was lowly associated with ST during these periods 2 years later (intraclass correlations from <0.001 to 0.364). Interventions in these settings may be adequate if the intention is to avoid ST increase in students. 相似文献