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131.
Many efforts have been made to reach educational equity, especially to reduce mathematics and science achievement gaps by students’ socioeconomic status. Across countries, educators strive to reform traditional teacher-centered instructional approaches to more student-centered/inquiry-based instruction to improve equity in education. In this context, this study examines whether relationships between socioeconomic status and scientific or mathematical literacy are moderated by student-centered instruction. Ten countries covering a wide range of achievement levels as well as equity in education are selected for an international comparison. A linear regression analysis is applied to student achievement, equity, and frequency of student-centered instruction data from the PISA 2012 and PISA 2015. We find mixed results: As student-centered instruction is offered more frequently, the gap in mathematical and scientific literacy between low and high socioeconomic status is generally narrowed or maintained. In most countries, students’ mathematical and scientific literacy scores are expected to decrease across all socioeconomic status as student-centered instruction is given more frequently. The findings necessitate further scrutiny of how teachers implement student-centered instruction in various educational systems. This further research need to consider the complexity of implementation related to sociological and pedagogical aspects.  相似文献   
132.
For diverse multiple access communication systems based on frame slotted aloha (FSA) protocol, it is important to analyze collision probability for the system performance evaluation. As shown in the literature, for general settings, it is difficult to derive an exact and closed-form solution for collision probability without approximation. Recently, an exact solution based on generic analytical approach (GAA) [31] has been proposed, yet its numerical computation will become difficult when the number of slots is larger than 16. In this paper, we develop an exact closed-form formula (ECFF) for collision probability that can not only overcome the computational deficiency of GAA in the presence of a large number of slots, but also reduce the computation complexity of collision probability. Surprisingly, by introducing a differentiation operator to form a hybrid recursive equation and applying various algebraic properties of Laplace transform and Z transform, the final collision probability can be represented by a compact double summation. Accuracy of the ECFF and comparison with the GAA have been studied by Monte Carlo simulation.  相似文献   
133.
Quantum information theory holds the promise of revolutionizing technologies other than computing and communications. In this article we show how quantum entanglement can be harnessed to beat the Rayleigh diffraction limit of conventional optical lithography, and to permit nano-devices to be fabricated at a scale arbitrarily shorter than the wavelength used. Given the relative ease of performing optical lithography compared with other schemes, and the relative costs associated in migrating the lithography industry to each new fabrication technology, exploiting quantum entanglement to extend the useful life of optical lithography could be economically attractive.  相似文献   
134.
International Review of Education - Drawing on critical theory for adult education, the authors of this article examine the Academic Credit Bank System (ACBS), an open educational system operating...  相似文献   
135.
This study reports a robust method of gene transfection in a murine primary cell model by using a high-density electrodes network (HDEN). By demonstrating high cell viability after gene transfection and successful expression of transgenes including fluorescent proteins, the HDEN device shows great promise as a solution in which reprogramming efficiency using non-viral induction for generation of murine induced pluripotent stem cells (iPSCs) is optimized. High and steady transgene expression levels in host cells of iPSCs can be demonstrated using this method. Moreover, the HDEN device achieved successful gene transfection with a low voltage of less than 180 V while requiring relatively low cell numbers (less than 1.5 × 104 cells). The results are comparable to current conventional methods, demonstrating a reasonable fluorescent-plasmid transfection rate (42.4% in single transfection and 24.5% in triple transfection) and high cell viability of over 95%. The gene expression levels of each iPSC factor was measured to be over 10-fold higher than that reported in previous studies using a single mouse embryonic fibroblast cell. Our results demonstrate that the generation of iPSCs using HDEN transfection of plasmid DNA may be a feasible and safe alternative to using viral transfection methods in the near future.  相似文献   
136.
This study tries to understand South Korean sport through the lens of media globalization. It explains what happened when Chan Ho Park gained fame in the Major League Baseball and how the Korean media sport market has changed since then. Due to the oligopolistic media market structure in Korea, and opportunistic behaviour, the sports media industry in Korea was not ready for media globalization and, consequently, the industry has seen indications of its marginalization in the global media market.  相似文献   
137.
Augmented reality (AR) has been recognized as a potential technology to help students link what they are observing in the real world to their prior knowledge. One of the most challenging issues of AR-based learning is the provision of effective strategy to help students focus on what they need to observe in the field. In this study, a competitive gaming approach is proposed to support AR-based learning activities conducted in real-world contexts. An experiment has been conducted on an elementary school ecology course to explore the effectiveness of the proposed approach in comparison with the conventional AR-based mobile learning approach in field trips. The experimental results show that the AR-based gaming approach can improve not only students' learning attitudes, but also their learning performance on the field trip. Accordingly, discussions and some suggestions for future work are provided.  相似文献   
138.
139.
This paper considers how the school science curriculum can be conceptualised in order to address the contingent and complex nature of environmental and sustainability‐related knowledge and understanding. A special concern lies in the development of research perspectives and tools for investigating ways, in which teachers are faced with complex and various situations in the sense‐making of science‐related issues, and subsequent pedagogic issues. Based on an empirical examination of Korean teachers’ sense‐making of their curricular practice, the paper develops a narrative approach to teachers’ perspectives and knowledge by considering the value of stories as sense‐making tools for reflective questioning of what is worth teaching, how and why. By employing the idea of ‘repertoire’, the study regards teachers’ stories about their environment‐related personal and teaching experiences as offering angles with which to understand teachers’ motivation and reflection in curricular development and implementation. Furthermore, three empirical cases present ways in which the nature of knowledge and understanding is recognised and potentially integrated into pedagogies through teachers’ narratives. Finally, the paper argues for the need to reconsider the role of the science teacher in addressing environmental and sustainability‐related issues, in ways that facilitate teachers’ reflexive interpretation of meanings in cultural texts and the construction of pedagogic text.  相似文献   
140.
In this paper, an adaptive TSK-type CMAC neural control (ATCNC) system via sliding-mode approach is proposed for the chaotic symmetric gyro. The proposed ATCNC system is composed of a neural controller and a supervisory compensator. The neural controller uses a TSK-type CMAC neural network (TCNN) to approximate an ideal controller and the supervisory compensator is designed to guarantee system stable in the Lyapunov stability theorem. The developed TCNN provides more powerful representation than the traditional CMAC neural network. Moreover, all the control parameters of the proposed ATCNC system are evolved in the Lyapunov sense to ensure the system stability with a proportional–integral (PI) type adaptation tuning mechanism. Some simulations are presented to confirm the validity of the proposed ATCNC scheme without the occurrence of chattering phenomena. Further, the proposed PI type adaptation laws can achieve faster convergence of the tracking error than that using integral type adaptation laws in previous published papers.  相似文献   
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