Total sliding-mode-based particle swarm optimization control for linear induction motor     

Rong-Jong Wai  Yeou-Fu LinKun-Lun Chuang 《Journal of The Franklin Institute》2014

In this study, a total sliding-mode-based particle swarm optimization control (TSPSOC) scheme is designed for the periodic motion control of an indirect field-oriented linear induction motor (LIM) drive. First, an indirect field-oriented mechanism for a LIM drive is introduced to preserve the decoupling control characteristic. Then, the concept of total sliding-mode control (TSC) is incorporated into particle swarm optimization (PSO) to form an on-line TSPSOC framework for preserving the robust control characteristics and reducing the chattering control phenomena of TSC. Moreover, an adaptive inertial weight is devised to accelerate the searching speed effectively. In this control scheme, a PSO control system is utilized to be the major controller, and the stability can be indirectly ensured by the concept of TSC without strict constraint and detailed system knowledge. With the proposed TSPSOC system, the mover position of the controlled LIM drive possesses the advantages of favorable robust characteristic, control effort without chattering, and simple control framework. Numerical simulations and experimental results are given to verify the effectiveness of the proposed control scheme for the tracking of periodic reference trajectories. In addition, the superiority of the proposed TSPSOC scheme is indicated in comparison with the TSC, Petri fuzzy-neural-network control (PFNNC) and traditional fuzzy-neural-network control (TFNNC) systems.  相似文献   

Construction of a eletrically sustained Rijke tube set-up     

Wai Hoong 《Resonance》2003,8(9):73-74

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Community‐Based Art Education in China: Practices,Issues and Challenges     

Ning Luo  Chung‐Yim Lau 《The International Journal of Art & Design Education》2020,39(2):445-460

Art educators have been promoting Community‐Based Art Education (CBAE) in schools in order to enhance students’ sense of socio‐cultural identity and contextual learning about local art and culture. It cannot only bridge the gap between the students’ daily lives and the communities and art, but can also enhance their inquiry, discovery and meaning‐making abilities. In China, the community‐based approach plays a significant role in the National Standards for Visual Arts, and Chinese art educators have been applying CBAE in school art education for decades. However, Western art educators are still unfamiliar with the issues, practices and challenges related to CBAE in China owing to language constraints. In light of the above, this article aims to initiate a dialogue between Western and Chinese CBAE researchers through discourse and discussions on the main issues related to CBAE in Chinese art education. It outlines current practices of, and issues related to, CBAE from the perspective of Chinese art education. It also discusses the three major challenges to the implementation of CBAE in China, namely the conflict between indigenous knowledge and official knowledge in the school art curriculum, lack of motivation among teachers, and neglect of context in the practice of local art in schools. It is hoped that this article it will enrich our overall knowledge of CBAE and contribute to the understanding of CBAE from a global perspective.  相似文献   

A Cognitive Learning Account of the Avoidance,Omission and Exaggerated Phenomena and Expressions in Young Adolescents’ Drawings of the Human Figure in the Visual Culture Art Education Context     

Chung‐yim Lau 《The International Journal of Art & Design Education》2020,39(3):686-703

It is common in the everyday art class to find many examples of avoidance, omission and exaggeration in young adolescents’ depictions of the human figure. When students depict sophisticated human images, they make every effort to avoid the difficult parts, and some students tend to exaggerate the size or distort the shape of the human image. Art educators see these types of behaviour and modes of expression as unnatural, and claim that they may hinder the development of the creativity of young adolescents. Relevant discussions in the literature from a psychological perspective are mainly concerned with the negative impact of such behaviour and modes of expression on the formation of young adolescents’ identities. However, in the context of popular visual culture, the findings of recent studies on young adolescents’ comic drawings have suggested that when young adolescents draw comic characters, they use their everyday life experiences in their drawings. This article reports on a five‐year qualitative longitudinal study conducted in a Hong Kong secondary school. The aim of the study was to deepen our understanding of this behaviour on the part of adolescents in art classes. The findings of the study confirmed the view that these aspects should be interpreted from a cognitive learning perspective. It is suggested that art educators reconsider these types of behaviour and modes of expression as a potential means for improving secondary students’ learning of the art of popular visual culture.  相似文献   

Hegemony and the politics of education in Hong Kong: from the post-war era to the post-handover era     

Tracy Chui Shan Lau 《Journal of educational administration and history》2018,50(4):241-255

ABSTRACT

The process of Chinese nation-building in education reveals the hegemonic strategies of the colonial power and the adaptation of indigenous forces when Hong Kong was undergoing decolonisation and the transfer of sovereignty. The return of Hong Kong to Chinese sovereignty has been a crucial indicator for the potential re-unification of China, as it presents a model for the possible future reintegration of Taiwan. The idea of hegemony applies to different dominant groups in the two periods under review. In the first period, London attempted to influence the development of groups in Hong Kong and incorporate them into the colonial programme. In the second period, Beijing attempts to influence groups in Hong Kong facilitate the reintegration of Hong Kong into a larger Chinese identity. Yet, it is far too simple to picture a unilateral exercise of power by an identifiable centre and consider the periphery as mere objects of successful manipulation by the centre. Continued study of the evolution of nation-building in education, under the influence of a series of complex and shifting factors of the Hong Kong society, will be enlightening for the comprehension of the ever-changing and increasingly complicated political culture.  相似文献   

纵向量表制作浅谈     

刘志明 《考试研究》2005,(2)

等值(equating)和纵向量表化(vertical scaling)的功用是建立来自不同考试的分数之间的关系。等值是施用于相同年级,相同性质的试卷,而纵向量表化则用于不同年级而性质相似的试卷。纵向量表化是将不同年级的成绩放置于统一的成长分数量表之中。纵向量表(vertical scale)是一种延伸的分数,其度量跨越和串连不同年级之间,用以评估学生连继性的成就成长(Nitko,2004)。在教学中,学生的进度可以利用纵向量表来监察和评估。而在教育研究上,纵向量表可成为长期跟踪调查(longitudinal study)之有力工具。本文讨论纵向量表化的方法论,包括成长定义(definition of growth),数据收集(data collection)方法,试卷设计和使用项目反应理论(Item Response Theory)的方法以及对制作纵向量表提供一些实际的建议。  相似文献   

Visual Instruction to Enhance Teaching of Technical Subject to Design Students     

Siu‐Kit Lau  Noopur Joshi  Ming Fai Pang 《The International Journal of Art & Design Education》2021,40(1):165-183

Visual instruction complementing verbal lectures is known to promote learning among students. In this study, the role of visual instruction in engaging learners effectively via the simplification of technical concepts was examined. Different aspects of visualisation, such as order of presenting and dimensionality, were tested to observe their effect on students’ approach to learning and learning outcomes. In this mixed‐method quasi‐non‐experimental explanatory study, visual instruction was applied in one of the undergraduate architecture modules that teaches fundamentals of building systems, which students often find difficult to comprehend. Three key variables, including spatial cognitive ability, approach to learning and learning outcomes, were measured using statistically valid instruments along with students’ feedback and interviews. These factors were also measured for the control group that did not receive visual instruction (n = 32), to assess the effect of the intervention. When taught with visualisation, students (n = 69), showed a significant increase in deep approach to learning (e.g., deep motive: t = 2.584, p = 0.011). In interviews, students expressed a deeper interest in the subject and reported that the topic was engaging in class. Visualisation favours students with a higher spatial ability and, thus, is useful for design students who receive spatial ability training in the course. Two‐dimensional visuals must be followed and preceded by three‐dimensional visuals to provide advanced organisation and the connection of new knowledge with known organisational models to be made.  相似文献   

Examining Hong Kong students’ achievement goals and their relations with students’ perceived classroom environment and strategy use     

Kit‐Ling Lau  John Lee 《教育心理学》2008,28(4):357-372

This study examined Hong Kong students’ achievement goals and their relations with students’ perceived classroom environment and strategy use based on the multiple goal perspective of goal orientation theory. A total of 925 Grade 8 students from six secondary schools in Hong Kong voluntarily responded to a questionnaire that measured these three sets of variables. Consistent with previous studies using goal orientation theory, the findings of this study indicated that students’ perceived classroom environment was significantly related to their personal achievement goals and strategy use. While mastery goals were found to be the strongest predictor of strategy use, performance‐approach goals and perceived instrumentality also had positive relations with mastery goals and strategy use. Our findings suggest that mastery goals and performance goals were not contrasting goals as conceptualised in normative goal orientation theory. Students with high motivation for both types of goal were more adaptive in learning than were students who pursued a single type of goal. Moreover, the value of adding perceived instrumentality when studying students’ motivation should be emphasised. The implications of these findings for understanding Hong Kong students’ motivation, and for planning effective teaching instruction to enhance their motivation, are discussed.  相似文献   

Technology integration for young children during COVID-19: Towards future online teaching     

Xinyun Hu  Ming Ming Chiu  Wai Man Vivienne Leung  Nicola Yelland 《British journal of educational technology : journal of the Council for Educational Technology》2021,52(4):1513-1537

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The Development of Diploma in Education Student Teachers’ Mathematics Pedagogical Content Knowledge     

Suat Khoh Lim-Teo  Kwee Gek Chua  Wai Kwong Cheang  Joseph K. Yeo 《International Journal of Science and Mathematics Education》2007,5(2):237-261

Mathematics pedagogical content knowledge (MPCK) of teachers cannot be easily defined but is a complex concept integrating generic pedagogical knowledge, mathematics teaching methodology as well as knowledge of the discipline of mathematics. It is the objective of mathematics methodology courses in teacher preparation programmes to begin the development of MPCK in their pre-service teachers. As part of a research study on the development of MPCK in primary school beginning teachers, a 16-item instrument was developed to measure some aspects of the MPCK for teaching mathematics at primary level. The instrument was administered to the 2003 Intake of the Diploma in Education student teachers at the National Institute of Education, Singapore just at the beginning of their programme. As they completed their methodology course in February 2005, the instrument was administered again. This paper will discuss the findings concerning their performance in these two tests, with reference to the overall performance as well as topic-specific and MPCK construct-specific performance. The findings indicate that student teachers at the beginning of their programmes are generally quite weak in their mathematics pedagogical content knowledge, as might be expected. There was significant improvement in some aspects of their MPCK on completion of their mathematics pedagogy course.  相似文献