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951.
Vince Geiger Kim Beswick Sharon Fraser Ben Holland-Twining 《British Educational Research Journal》2023,49(5):900-924
In this paper we develop a model for the capabilities required by principals for effective Science, Technology, Engineering and Mathematics (STEM) leadership. The model underpinned a large national cross-sectional research and development project across Australian states in both primary and secondary schools. This model is developed via synthesis of research literature across leadership and STEM education. The model consists of five dimensions of principals' STEM capability: (1) STEM discipline-specific and integrated knowledge and practices; (2) contexts; (3) dispositions; (4) tools; and (5) critical orientation. These dimensions represent distinct, but interrelated, capacities required by principals to establish and maintain positive STEM learning cultures within schools. Elaborations have been provided, in the form of capabilities, for each of these dimensions. The model has the potential for shaping principals' STEM leadership development trajectories and structuring targeted professional learning programmes for principals, teachers and other members of the school community. 相似文献
952.
Kwon Kyong-Ah Ford Timothy G. Salvatore Alicia L. Randall Ken Jeon Lieny Malek-Lasater Adrien Ellis Natalie Kile Mia S. Horm Diane M. Kim Sun Geun Han Minkyung 《Early Childhood Education Journal》2022,50(1):169-171
Early Childhood Education Journal - The original version of this article unfortunately contains some typo in Table 1. 相似文献
953.
Kim Nam Ju Vicentini Cristiane Rocha Belland Brian R. 《International Journal of Science and Mathematics Education》2022,20(2):215-236
International Journal of Science and Mathematics Education - Success in problem-based learning requires both strong information literacy to search for, evaluate, and use information effectively,... 相似文献
954.
Junghoon Kim 《The Information Society》2013,29(4):307-308
Abstract In this paper, an analysis is provided of data to evaluate the extent to which investment in information resources can be demonstrated to have direct value in greater industrial profitability. Specifically, it examines the statistical relationship between “added value” for the manufacturing industries of the country and the investment they make in purchased information services. A review is presented of the context of evaluation of the value of information, with anecdotal evidence concerning its role. We review the theoretical background for the analysis and describe the data on which the analysis is based. The discussion of data covers the sources, the nature, and the structure of the data sets and provides a detailed listing of the data itself. We also present the results of the analysis, discuss the implications, and conclude with a commentary on potential problems due to the heterogeneous character of the data, including the analysis of a range of alternative models all of which produce the same qualitative results that were obtained in the basic regression. We apply a Cobb‐Douglas model to value added as a function of labor, capital, purchases of information services, and purchases of other input. We do a regression analysis for that model on 50 manufacturing industries, using data from 1967, and 51 industries, using data from 1972. The theory states that, if industry is operating in an optimal manner, the marginal return from the external purchases (whether for information services or for other input), as expressed by the coefficient in the regression, should be zero. If the coefficient is positive, industry is not using enough of the external resource; if negative, industry is using too much of it. Our results show that there is a demonstrable relationship between increased added value (and therefore profitability) and investment in information resources. Beyond that, the evidence suggests that manufacturing industry is using far less than the optimal amount of information resources than should be optimal. 相似文献
955.
956.
Anna Palczewska Xin Fu Paul Trundle Longzhi Yang Daniel Neagu Mick Ridley Kim Travis 《International Journal of Information Management》2013
Efficient management of toxicity information as an enterprise asset is increasingly important for the chemical, pharmaceutical, cosmetics and food industries. Many organisations focus on better information organisation and reuse, in an attempt to reduce the costs of testing and manufacturing in the product development phase. Toxicity information is extracted not only from toxicity data but also from predictive models. Accurate and appropriately shared models can bring a number of benefits if we are able to make effective use of existing expertise. Although usage of existing models may provide high-impact insights into the relationships between chemical attributes and specific toxicological effects, they can also be a source of risk for incorrect decisions. Thus, there is a need to provide a framework for efficient model management. To address this gap, this paper introduces a concept of model governance, that is based upon data governance principles. We extend the data governance processes by adding procedures that allow the evaluation of model use and governance for enterprise purposes. The core aspect of model governance is model representation. We propose six rules that form the basis of a model representation schema, called Minimum Information About a QSAR Model Representation (MIAQMR). As a proof-of-concept of our model governance framework we develop a web application called Model and Data Farm (MADFARM), in which models are described by the MIAQMR-ML markup language. 相似文献
957.
Young Sik Kang Jinyoung Min Jeoungkun Kim Heeseok Lee 《International Journal of Information Management》2013
Individuals with a positive evaluation of a target system are likely to continue using the system, and this sustained use is likely to result in continued use. This target-oriented perspective has served as a major conceptual framework for understanding users’ behaviors in online contexts. The primary objective of this paper is to address two additional perspectives—alternative- and self-oriented perspectives—for a firmer understanding of continued use in the context of social network sites (SNS). A research model is built by employing regret and self-image congruity to represent these two perspectives. The model also examines the condition under which habits are formed and how this automatic mechanism influences the dynamics of the nomological network between intentions and behaviors. The analysis results of two rounds of surveys for capturing the actual link between intentions and behaviors indicate that regret and self-image congruity can play crucial roles in post-adoption phenomena in the context of SNS. 相似文献
958.
Microfluidic systems have shown unequivocal performance improvements over conventional bench-top assays across a range of performance metrics. For example, specific advances have been made in reagent consumption, throughput, integration of multiple assay steps, assay automation, and multiplexing capability. For heterogeneous systems, controlled immobilization of reactants is essential for reliable, sensitive detection of analytes. In most cases, protein immobilization densities are maximized, while native activity and conformation are maintained. Immobilization methods and chemistries vary significantly depending on immobilization surface, protein properties, and specific assay goals. In this review, we present trade-offs considerations for common immobilization surface materials. We overview immobilization methods and chemistries, and discuss studies exemplar of key approaches—here with a specific emphasis on immunoassays and enzymatic reactors. Recent “smart immobilization” methods including the use of light, electrochemical, thermal, and chemical stimuli to attach and detach proteins on demand with precise spatial control are highlighted. Spatially encoded protein immobilization using DNA hybridization for multiplexed assays and reversible protein immobilization surfaces for repeatable assay are introduced as immobilization methods. We also describe multifunctional surface coatings that can perform tasks that were, until recently, relegated to multiple functional coatings. We consider the microfluidics literature from 1997 to present and close with a perspective on future approaches to protein immobilization. 相似文献
959.
Toshiki Matsuoka Byoung Choul Kim Christopher Moraes Minsub Han Shuichi Takayama 《Biomicrofluidics》2013,7(4)
This short review provides an overview of the impact micro- and nanotechnologies can make in studying epigenetic structures. The importance of mapping histone modifications on chromatin prompts us to highlight the complexities and challenges associated with histone mapping, as compared to DNA sequencing. First, the histone code comprised over 30 variations, compared to 4 nucleotides for DNA. Second, whereas DNA can be amplified using polymerase chain reaction, chromatin cannot be amplified, creating challenges in obtaining sufficient material for analysis. Third, while every person has only a single genome, there exist multiple epigenomes in cells of different types and origins. Finally, we summarize existing technologies for performing these types of analyses. Although there are still relatively few examples of micro- and nanofluidic technologies for chromatin analysis, the unique advantages of using such technologies to address inherent challenges in epigenetic studies, such as limited sample material, complex readouts, and the need for high-content screens, make this an area of significant growth and opportunity. 相似文献
960.
Yongnam Kim 《Journal of Educational Measurement》2020,57(4):511-526
Does reviewing previous answers during multiple-choice exams help examinees increase their final score? This article formalizes the question using a rigorous causal framework, the potential outcomes framework. Viewing examinees’ reviewing status as a treatment and their final score as an outcome, the article first explains the challenges of identifying the causal effect of answer reviewing in regular exam-taking settings. In addition to the incapability of randomizing the treatment selection (reviewing status) and the lack of other information to make this selection process ignorable, the treatment variable itself is not fully known to researchers. Looking at examinees’ answer sheet data, it is unclear whether an examinee who did not change his or her answer on a specific item reviewed it but retained the initial answer (treatment condition) or chose not to review it (control condition). Despite such challenges, however, the article develops partial identification strategies and shows that the sign of the answer reviewing effect can be reasonably inferred. By analyzing a statewide math assessment data set, the article finds that reviewing initial answers is generally beneficial for examinees. 相似文献