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31.
Teachers’ knowledge of STEM education, their understanding, and pedagogical application of that knowledge is intrinsically linked to the subsequent effectiveness of STEM delivery within their own practice; where a teacher’s knowledge and understanding is deficient, the potential for pupil learning is ineffective and limited. Set within the context of secondary age phase education in England and Wales (11–16 years old), this paper explores how teachers working within the field of design and technology education acquire new knowledge in STEM; how understanding is developed and subsequently embedded within their practice to support the creation of a diverse STEM-literate society. The purpose being to determine mechanisms by which knowledge acquisition occurs, to reconnoitre potential implications for education and learning at work, including consideration of the role which new technologies play in the development of STEM knowledge within and across contributory STEM subject disciplines. Underpinned by an interpretivist ontology, work presented here builds upon the premise that design and technology is an interdisciplinary educational construct and not viewed as being of equal status to other STEM disciplines including maths and science. Drawing upon the philosophical field of symbolic interactionism and constructivist grounded theory, work embraces an abductive methodology where participants are encouraged to relate design and technology within the context of STEM education. Emergent findings are discussed in relation to their potential to support teachers’ educational development for the advancement of STEM literacy, and help secure design and technology’s place as a subject of value within a twenty-first Century curriculum.  相似文献   
32.
The paper considers two rival models referring to the new macroeconomic consensus: a standard three-equation model of the New-Keynesian variety versus dynamic adjustments of a business and an inflation climate in an ‘Old-Keynesian’ tradition. Over the two subperiods of the Great Inflation and Great Moderation, both of them are estimated by the method of simulated moments. An innovative feature is here that the moments do not only include the autocovariances up to eight lags of quarterly output, inflation and the interest rate, but optionally also a measure of the raggedness of the three variables. In short, the performance of the Old-Keynesian model is very satisfactory and similar to the New-Keynesian model, or even better. In particular, the Old-Keynesian model is better suited to match the new moments without deteriorating the original second moments too much.  相似文献   
33.
Replanning is often used to optimize results of an activity in an ever changing world. To address the challenge of preparing future engineers for success, a special course was created for all engineering freshmen of the Faculty of Engineering of the University of Porto, in Portugal. Presented as a case study, this special course underwent a careful replanning as a result of several years of experience in teaching practice alongside with a theoretical deepening in pedagogical and technological issues, under the aegis of the action-research methodology. Within the context of the case study course, the mentioned replanning was also based on a theoretical approach that clearly identifies teaching–learning-assessment methodologies that promote regulation from those that foster emancipation, using a specific instrument: a taxonomy of educational processes. The replanning was designed to globally boost results regarding the educational aims of the course such as furthering freshmen’s integration into work environment and preparing them for success by fostering transversal skills (needed for study and work). Technology is seen as a mean of education enrichment as well as a productivity tool. The introduced innovations include fun-but-educational activities, several types of assessment over time and specific technological tools which were critical for the educational impact/achievement of this course. Success is demonstrated by encouraging feedback from the stakeholders, high students’ classifications and a steady reduction in retention. It is advocated that large portions of the reasoning behind the replanning can be extrapolated to other courses.  相似文献   
34.
Ecosystem transformation and climate change evolve over long time scales. The effects of the economic decisions on the natural environment are also of a long-run character because they relate to investment decisions and capital stocks. At the same time, the economy is short-sighted and subject to different kinds of market failures. The time it takes to notice the changes and adequately address the associated problems affects the dynamics and inertia of the process. We discuss some recent contributions and new research questions that deal with time and timing in environmental and resource economics.  相似文献   
35.
This paper examines the pattern of settlements, investor wins and state wins in investor-state dispute settlement cases, focusing on the impact of arbitration rules, the resources and experience of the litigants, the type of treaty breach under investigation, and the pattern of state intervention. Logistic regression results show that settlements are more likely when investors do not disclose their allegations publicly, when the host state has been involved in a greater number of past cases, and when the respondent state has a higher control-of-corruption rating. Panel awards to investors are more likely in cases of alleged direct expropriation and less likely for indirect expropriation. Panel decisions favoring the state increase with higher per capita income and rule-of-law ratings.  相似文献   
36.
37.
This paper focuses on entrepreneurship by academic leaders. With the use of patents, inventions, and spin‐offs to measure commercialization, and directors, research group leaders, and business owners as academic leaders, results, using a sample of more than 2,500 German researchers, show differences across academic leaders and commercialization. Findings for spin‐offs are different from those for patents and inventions. Academic leaders in sciences were more likely to commercialize. Doctoral degrees helped patents by business owners and spin‐offs by group leaders, whereas female business owners and female group leaders faced challenges patenting and inventing, respectively. For business owners, age increased the likelihood of patenting but lowered spin‐offs.  相似文献   
38.
Supersaturated designs (SSDs) constitute an important class of fractional factorial designs that could be extremely useful in factor screening experiments. Most of the existing studies have focused on balanced designs. This paper provides a new lower bound for the \(E(f_{NOD})\)-optimality measure of SSDs with general run sizes. This bound is a generalization of existing bounds since it is applicable to both balanced and unbalanced designs. Optimal multi and mixed-level, balanced and nearly balanced SSDs are constructed by applying a k-circulant type methodology. Necessary and sufficient conditions are introduced for the generator vectors, in order to pre-ensure the optimality of the constructed k-circulant SSDs. The provided lower bounds were used to measure the efficiency of the generated designs. The presented methodology leads to a number of new families of improved SSDs, providing tools for directly constructing optimal or nearly-optimal k-circulant designs by just checking the corresponding generator vector.  相似文献   
39.
Nowadays, the economic activities have become increasingly digital since hundreds of millions of Internet users are using crowdsourcing platforms either to work at an online job as workers, or as a model of problem-solving and production as requesters. This growing workforce makes it necessary from the perspective of the online platforms, to fully understand the business dimensions of this emerging and innovative “online labor” phenomenon, which can rapidly change the future of work and work organization in the online world. This paper aims to investigate and analyze the visits of online labor platforms that offer crowdsourcing and crowdfunding services. Using websites’ metrics data drawn from Alexa for the time period 2012-2016 the paper uses Ordinary Least Squares (OLS) and Fixed Effects (FE) regression analysis to examine correlations between visits and website characteristics. The research shows that the sessions of an online labor marketplace website from mobile devices have an increasing trend to be positively correlated to the quality mechanisms a website deploys as well as on location-dependent factors. The results are expected to provide insights on how the online labor website characteristics affect their traffic and thus inform about their evolution and improvement.  相似文献   
40.
In this paper, while focusing on the impact that the global financial crisis had on the stock markets of China, Japan, and the United States, the stock-price volatilities and linkage between these three countries are analyzed. In addition, the relationships between macroeconomic variables (real-economy variables and monetary-policy variables) and stock price volatility in each country are investigated. The estimation results of the EGARCH model revealed that although China’s stock price volatility was far greater than those of Japanese and US stock prices, China was less affected by the global financial crisis in 2007 than Japan and the United States. For China, stock price volatility was greater in the early 1990s, shortly after the stock market had been established, than in 2007 when the global financial crisis occurred. Furthermore, it has been revealed that the linkage of Chinese, Japanese, and US stock prices has increased since the global financial crisis. Moreover, Granger causality testing revealed China’s real-economy variables and monetary-policy variables do not affect China’s stock price volatility.  相似文献   
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