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41.
This paper describes one approach to the design of reinforced concrete (RC) bridge piers, using a three-hybrid multi-objective simulated annealing (SA) algorithm with a neighborhood move based on the mutation operator from the genetic algorithms (GAs), namely MOSAMO1, MOSAMO2 and MOSAMO3. The procedure is applied to three objective functions: the economic cost, the reinforcing steel congestion and the embedded CO2 emissions. Additional results for a random walk and a descent local search multi-objective algorithm are presented. The evaluation of solutions follows the Spanish Code for structural concrete. The methodology was applied to a typical bridge pier of 23.97 m in height. This example involved 110 design variables. Results indicate that algorithm MOSAMO2 outperforms other algorithms regarding the definition of Pareto fronts. Further, the proposed procedure will help structural engineers to enhance their bridge pier designs.  相似文献   
42.
This paper presents the development and structure of indigenous children’s ideas about mixing colours as well as their ideas about each colour, derived from their traditions. The children were interviewed both at school and outside it, and an educational proposal was implemented. Ideas expressed in the school context were analysed using the partial possible model, which states that the inferences and explanations used to describe a subject consist of constricting ideas, rules of correspondence, and a set of phenomenological inferences about processes. After identifying these components in the children’s ideas, we developed models to describe their conceptions about mixing colours. We employed a different approach to analyse children’s ideas related to their cultural context. The results showed that children change from a conception that focuses on colours as entities that do not change and as properties of objects (model 1) to the idea that colour represents a quality of substances or objects that can be modified by mixing colours (model 2). Cultural context analysis showed that stories are independent from one another and that they are not connected to colour mixing processes, only to the actions of colour on people. We concluded that students generate independent constructions between school and cultural knowledge.  相似文献   
43.
In terms of international education, the concept of online education seems to be a growing trend. Edxonline.org, Minervaproject.com, and Udacity.com are all new massive online open courses (MOOCs)—education websites similar to Coursera offering students the ability to receive the best education from elite universities entirely online. The most tantalizing promise of a company like Coursera is the role it might play in improving education for the world's have-nots: high school dropouts, the global poor, and those less able to self-teach.  相似文献   
44.
This study performs a systematic content analysis of Indian English green print advertisements for the years 2010 and 2011 to verify if greenwashing is prevalent. Green advertisements were analysed based on four dimensions – (1) claim specificity, (2) greenwashing category, (3) incidence of associative claims and (4) presence of certifications. The results indicate that 51.7% of the claims were greenwashed and most of them were vague or ambiguous (37.7%). Most claims lacked specificity (67.0%) and image claims (60.0%) were widely used. Very few advertisements (3.3%) employed certifications to substantiate their claims. Interestingly, we also found that more than half of the image-related claims (55.8%) were categorized as misleading and highly specific claims were considered acceptable. We suggest that either the self-regulatory body – the Advertising Standards Council of India – or the legal regulatory framework accommodate well-defined provisions for regulating green claims in advertisements to curb greenwashing.  相似文献   
45.
The purpose of this research was to build and test a conceptual model of the complex interrelationships between students' learning in science (learning approaches and self-regulation), their reading comprehension, question-asking in class and science achievement. These variables were measured by means of a test and a series of questionnaires administered to 604 ninth-grade students, and the data collected were analysed using a correlational, cross-sectional design. Results of a path analysis indicated that (a) students’ self-regulated and intentional knowledge-constructing activity (self-regulated strategy use, deep approach and knowledge-building) were what chiefly accounted for their question-asking in class; (b) question-asking (high and low levels) was related directly to reading comprehension and indirectly, through its contribution to the this, to academic achievement; (c) reading comprehension was directly and negatively associated with surface approach and indirectly and positively related to deep approach and knowledge-building; and (d) some of these variables, particularly reading comprehension, accounted for academic achievement in science. This model explained nearly 30% of the variance in academic achievement and provided a substantial and distinctive insight into the web of interrelationships among these variables. Implications for future research and science teaching and learning are discussed (e.g. the importance of supporting students' efforts to learn science in a meaningful, active and self-regulated way and of improving their reading comprehension).  相似文献   
46.
This article summarizes recent efforts by Latin-American theologians concerned with developing a pluralist theology of liberation. The author highlights some of the most significant issues and themes of this emerging theological reflection among liberation theologians. Finally, he identifies some of the challenges a pluralist theology of liberation raises for our task as religious educators in North America.  相似文献   
47.
The current study analyzes the processes involved in obtaining technological innovations. Conclusive results are lacking in the literature, so this work defines and empirically tests a model of the relations between the firm's innovative capacity and the different ways of accumulating knowledge and the decision whether or not to codify it. Also, the model takes into account whether the innovations obtained are radical or incremental.The empirical study uses a sample of Spanish biotechnology firms, and the results show that accumulating knowledge using internal sources and not codifying it significantly improves the firm's capacity to develop radical innovations. The results also show that knowledge codification speeds up the development of incremental innovations. The relation between incremental innovations and the sources of knowledge is not so clear, although the results suggest the possible existence of a nonlinear relation between the two variables.  相似文献   
48.
The objective of this paper is to propose a methodology for applying knowledge management (KM), in which we first focus on explaining problematic areas of an organization by identifying the knowledge core process, before applying KM strategies to those processes. For the methodology, we lean on the larger context of systems thinking to help visualize the whole organization, and it is here that the key factors are identified and a set of strategic criteria is established. The most important criteria are then used to evaluate the associated processes and their respective tasks in order to establish the problematic areas or opportunities where KM initiatives can be applied. This strategy precludes tackling all the organization's problems and allows management to focus on only those processes that provide significant and manageable knowledge. Finally, this study explores and cautiously recommends an unexploited but valuable element to be taken into account when implementing KM initiatives.  相似文献   
49.
BackgroundConsidering the potential cumulative effects of repetitive head impact (HI) exposure, we need sensitive biomarkers to track short- and long-term effects. Circulating small extracellular vesicles (sEVs) (<200 nm) traffic biological molecules throughout the body and may have diagnostic value as biomarkers for disease. The purpose of this study was to identify the microRNA (miRNA) profile in circulating sEVs derived from human plasma following repetitive HI exposure.MethodsHealthy adult (aged 18–35 years) soccer players were randomly assigned to one of 3 groups: the HI group performed 10 standing headers, the leg impact group performed 10 soccer ball trapping maneuvers over 10 min, and the control group did not participate in any soccer drills. Plasma was collected before testing and 24 h afterward, and sEVs were isolated and characterized via nanoparticle tracking analysis. Next-generation sequencing was utilized to identify candidate miRNAs isolated from sEVs, and candidate microRNAs were analyzed via quantitative polymerase chain reaction. In silico target prediction was performed using TargetScan (Version 7.0; targetscan.org) and miRWalk (http://mirwalk.umm.uni-heidelberg.de/) programs, and target validation was performed using luciferase reporter vectors with a miR-7844-5p mimic in human embryonic kidney (HEK) 293T/17 cells.ResultsPlasma sEV concentration and size were not affected across time and group following repetitive HI exposure. After 24 h, the HI read count from next-generation sequencing showed a 4-fold or greater increase in miR-92b-5p, miR-423-5p, and miR-24-3p and a 3-fold or greater decrease in miR-7844-5p, miR-144-5p, miR-221-5p, and miR-22-3p. Analysis of quantitative polymerase chain reaction revealed that leg impact did not alter the candidate miRNA levels. To our knowledge, miR-7844-5p is a previously unknown miRNA. We identified 8 miR-7844-5p mRNA targets: protein phosphatase 1 regulatory inhibitor subunit 1B (PPP1R1B), LIM and senescent cell antigen-like domains 1 (LIMS1), autophagy-related 12 (ATG12), microtubule-associated protein 1 light chain 3 beta (MAP1LC3B), integrin subunit alpha-1 (ITGA1), mitogen-activated protein kinase 1 (MAPK1), glycogen synthase kinase 3β (GSK3β), and mitogen-activated protein kinase 8 (MAPK8).ConclusionCollectively, these data indicate repetitive HI exposure alters plasma sEV miRNA content, but not sEV size or number. Furthermore, for the first time we demonstrate that previously unknown miR-7844-5p targets mRNAs known to be involved in mitochondrial apoptosis, autophagy regulation, mood disorders, and neurodegenerative disease.  相似文献   
50.
This article examines the leadership approach of the football coach José Mourinho, particularly of the relevance of the media for his top performance at Porto (2002–2004), Chelsea (2004–2007), Inter Milan (2008–2010) and Real Madrid (2010–2013). The perspective from which we analyse the work of Mourinho in that period, and his presence in the media, is based on what science calls the paradigm of complexity. This is a relational perspective which, in this case, means not only focusing upon the actions ‘central’ to the activity in question – the technique, tactics, physical preparation and so on – but, with particular relevance, detail and in an integrated fashion, also focusing on the media and the cultural context in which the activity takes place. Key to the transformational work of José Mourinho is his presence in the media, the managing of fame, the challenges and ambitions of the players, the fans and the general public. At stake is a personification of a global system of significance.  相似文献   
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