• Nuclear Engineering and Technology
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• v.56 no.6
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• pp.2282-2291
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• 2024

In this work we study the effects of different factors of dislocation loop on its obstacle strength when interacting with an edge dislocation. At first, the interaction model for dislocation and dislocation loop is established and the full and partial absorption mechanism is obtained. Then, the effect of temperature, size and burgers vector of dislocation loop are investigated. The relation between the obstacle strength and irradiation dose has been established, which bridges the irradiation source and microscale properties. Except that, the obstacle strength of C, Cr, Ni, Mn, Mo and P decorated dislocation loop is studied. Results show that the obstacle strength for dislocation loop decorated by alloy element decreases in the sequence of Cr, Ni, Mn, C, P and Mo, which could be used to help parameterize and validate crystal plasticity finite element model and therein integrated constitutive laws to enable accounting for irradiation-induced chemical segregation effects.

• Journal of the Korean Wood Science and Technology
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• v.50 no.5
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• pp.325-337
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• 2022

Grewia serrulata fibres were chemically treated with 3%, 6%, and 9% NaOH for the duration of 4 h. Additionally, the NaOH-treated fibres were also treated with 3 - (trimethoxysilyl) propyl methacrylate (silane). Properties such as density and tensile strength of the treated fibres were compared against the untreated fibres. The highest density was obtained in the case of 9% NaOH + silane treated fibres, which was 26.47% higher than untreated fibres, implying effective removal of hemicellulose. Likewise, the highest tensile strength was also obtained in the case of 9% NaOH + silane treated fibres. The increment observed in the tensile strength of the natural fibres was related to the removal of impurities, hemicellulose, and stress-raisers as well as deposition over the fibre surface that smoothed it. These observations were further validated by estimating changes in chemical constituents due to chemical treatment along with characterization techniques such as scanning electron microscopy and thermogravimetric analysis.

• Research in Mathematical Education
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• v.10 no.1 s.25
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• pp.71-78
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• 2006

Gifted education has been becoming a focus of every field in Chinese society as a special educational mode, since Special Class for the Gifted Youth in the University of Science and Technology of China began to enroll students. In this paper we first introduce the developing procedure of the gifted education in China, and then recommend and analyze the characteristics of a successful gifted educational base in China. At length, we probe into the problems that exist in process of carrying on the gifted education in China for reference.

• Journal of Chest Surgery
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• v.54 no.5
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• pp.331-332
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• 2021

• Educational Technology International
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• v.21 no.1
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• pp.31-67
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• 2020

The purpose of this study was to propose an education cooperation model for Human Resources Development (HRD) in Asia-Pacific region in response to environmental changes in business and industry. In order to carry out the model, this study reviewed the key features of human resources in the APEC which is a symbolic regional integration entity in Asia-Pacific region, shaped critical issues related with HRD in this region and then analyzed the trends of education cooperation projects conducted by the APEC in terms of topics, implementation methods and proposing economies of the projects. In result, this study proposed a triangular education cooperation model for HRD consisting of three elements: Voluntary Partnership, Information on Needs and Support for Cooperation. These interconnected and interdependent elements were designed to encourage actors to participate in education cooperative activities with their own willingness, produce and manage research-based information required for sustainable cooperation and support communication and connectivity among actors for effective activities. Also, this study expected that this model would make a commitment to narrowing educational divides, enhancing global-standard skills development, facilitating public and private partnership and organizing the foundation of future education for cultivating creative talents in the era of innovation for APEC members.

• Journal of Engineering Education Research
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• v.15 no.4
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• pp.8-13
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• 2012

The Engineering school of Tohoku University has been offering a Team-based Engineering Design Course to its first year students since 1996 in order to increase the level of both motivation and interest in engineering. Freshmen are required to select one of approximately 150 topics and do some research on this topic. This course also provides opportunities for students to participate in exchange programs with the University of Washington (UW) and the University of Science and Technology Beijing (USTB). In the Tohoku-UW exchange program, which began in 1999, between 10 and 25 students of Tohoku visit the UW annually to present the results of the subjects the school has appointed in advance in the Team-based Engineering Design Course. In the Tohoku-USTB exchange program, which began in 2007, about 15 students from each university participate in a one day meeting organized by the students themselves. They give a presentation on either the results of the subject they selected in the course, or on an engineering related topic both groups have agreed to in advance. In this paper, a detailed history, the objectives, a schedule and the budget in these unique exchange programs is introduced together with an outline of the course and its contribution to the engineering design education.

• Journal of The Korean Association For Science Education
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• v.23 no.4
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• pp.386-400
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• 2003

This paper presents an analysis of the Developmental Approaches in Science, Health and Technology (DASH) program, a K-6 curriculum developed by the Curriculum Research & Development Group (CRDG) at the University of Hawaii employing the curriculum analysis framework created by Posner. Using this framework the analyst found that the DASH design is based on the research on learning, teaching, and assessment now driving efforts to reform science education at the elementary level. DASH embraces the constructivist idea that learning is a personal and social process and the recapitulation model that new concepts are built out of theories previously learned. DASH provides an understandable, exciting, and memorable experience in the operations of science, health, and technology, and develops their capacity to use the skills and knowledge of science, health, and technology both in and outside school. A number of studies of DASH have examined its functionality, effectiveness of pedagogy and what students learn. The innovative nature of DASH necessitated a multidimensional assessment that included both quantitative and qualitative research techniques. Ongoing development of the DASH program in the research setting of a university laboratory school permits ever deeper connections with emerging curriculum theory and curriculum practice, and allows new linkages as ideas are tested in research classrooms.

• Journal of Electrical Engineering and Technology
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• v.12 no.3
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• pp.1016-1026
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• 2017

An adaptive extended Kalman filter based on the maximum likelihood (EKF-ML) is proposed for detecting voltage sag in this paper. Considering that the choice of the process and measurement error covariance matrices affects seriously the performance of the extended Kalman filter (EKF), the EKF-ML method uses the maximum likelihood method to adaptively optimize the error covariance matrices and the initial conditions. This can ensure that the EKF has better accuracy and faster convergence for estimating the voltage amplitude (states). Moreover, without more complexity, the EKF-ML algorithm is almost as simple as the conventional EKF, but it has better anti-disturbance performance and more accuracy in detection of the voltage sag. More importantly, the EKF-ML algorithm is capable of accurately estimating the noise parameters and is robust against various noise levels. Simulation results show that the proposed method performs with a fast dynamic and tracking response, when voltage signals contain harmonics or a pulse and are jointly embedded in an unknown measurement noise.

• Nuclear Engineering and Technology
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• v.51 no.4
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• pp.1132-1141
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• 2019

Steel-concrete-steel (SCS) sandwich structures have important advantages over conventional concrete structures, however, bond-slip between the steel plate and concrete may lead to a loss of composite action, resulting in a reduction of stiffness and fatigue life of SCS sandwich structures. Due to the inaccessibility and invisibility of the interface, the interfacial performance monitoring and debonding detection using traditional measurement methods, such as relative displacement between the steel plate and core concrete, have proved challenging. In this work, two methods using piezoelectric transducers are proposed to detect the bond-slip between steel plate and core concrete during the test of the beam. The first one is acoustic emission (AE) method, which can detect the dynamic process of bond-slip. AE signals can be detected when initial micro cracks form and indicate the damage severity, types and locations. The second is electromechanical impedance (EMI) method, which can be used to evaluate the damage due to bond-slip through comparing with the reference data in static state, even if the bond-slip is invisible and suspends. In this work, the experiment is implemented to demonstrate the bond-slip monitoring using above methods. Experimental results and further analysis show the validity and unique advantage of the proposed methods.

• Journal of The Korean Association of Information Education
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• v.10 no.1
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• pp.25-35
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• 2006

Computer education currently executed at elementary schools showed problems of system of education curriculum, repetition, and lack of consistent system as a result of analyzing index for information and communication technology, education curriculum, and related literatures, and most of the education contents have difficulty to nurture logic thinking and problem-solving ability since they are composed mainly of software function learning. Concerning this issue, this study suggests an innovated computer education curriculum with reinforced information ethics field with computer principle, algorithm, and programming, in other words, a corrected and supplemented version of former content system based on computer science guidance cases of ACM education curriculum model of USA, computer education curriculum of state Tennessee, and information technology education curriculum of Great Britain judging that introduction of computer science factors are desperate to improve computer education curriculum in elementary schools.