• Structural Engineering and Mechanics
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• v.73 no.2
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• pp.123-132
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• 2020

Steel spherical hinged bearings have high loading capacity, reliable load transfer, flexible rotation with universal hinge and allowance of large displacement and rotation angle. However, bearings are in complex forced states subject to various load combinations, which lead to the significant influence on integral structural safety. Taking the large-tonnage complex steel spherical hinged bearings of Terminal 2 of Guangzhou Baiyun International Airport as an example, full-scale rotation and shear behaviour tests of the bearings subject to axial tensile load are carried out, and the corresponding finite element simulation analyses are conducted. The results of experiments and finite element simulations are in good agreement with the coincident development tendency of stress and deformation. In addition, the measured rotational moment is less than the calculated moment prescriptive by the code, and the relationship between horizontal displacement and horizontal shear force is linear. Finally, based on these results, the rotation and shear stiffness models of bearings subject to axial tensile load are proposed for the refinement analysis of integral structure.

• Structural Engineering and Mechanics
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• v.45 no.4
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• pp.521-542
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• 2013

In this study a truss model is used for the geometrically nonlinear static and dynamic analysis of a thin shallow arch subject to snap-through. Thanks to the very simple geometry of a truss, the equilibrium conditions can be easily written and the global stiffness matrix can be easily updated with respect to the deformed structure, within each step of the analysis. A very coarse discretization is applied; so, in a very simple way, the high frequency modes are suppressed from the beginning and there is no need to develop a complicated reduced-order technique. Two short computer programs have been developed for the geometrically nonlinear static analysis by displacement control of a plane truss model of a structure as well as for its dynamic analysis by the step-by-step time integration algorithm of trapezoidal rule, combined with a predictor-corrector technique. These two short, fully documented computer programs are applied on the geometrically nonlinear static and dynamic analysis of a specific thin shallow arch subject to snap-through.

• Proceedings of the KOSOMBE Conference
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• v.1998 no.11
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• pp.84-85
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• 1998

This study was conducted to characterize the gait of a person climbing or descending the stairs. Using our motion analysis system (Vicon 370), gait patterns of ten healthy females (18.8 - 19.6 yrs. old) were measured 1) when a subject tip-toed the stairs, 2) when a subject climbs the stairs with the whole foot, and 3) when a subject went down the stair, respectively. The results of each cases were compared with the data for the level walking collected from 21 healthy females in the previous studies. The stairway gait data can be used as a useful reference in the design of artificial limbs for the lower-limb amputee.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.11 no.17
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• pp.15-23
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• 1988

The subject in this paper is to apply the ellipsoid method proposed by khachiyan〔1〕 to ILP systems. For solving ILP problems we will present a algorithm using the modified formular of Pallaschke〔2〕. Additionally, computational results indicate that out algorithm is subject to the numerical stability.

• Journal of the Korean Society for Library and Information Science
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• v.26
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• pp.213-233
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• 1994

This study measured whether subject descriptor searching and citation searching retrieve different documents for conceptual queries and methodological queries in natural science, engineering and social science. The retrieval effectiveness of two search methods was measured using as criteria, total number of documents retrieved, total number of relevant documents, overlapping and unique documents and precision ratio. The search subject was water resources and the databases used were Selected Water Resources Abstracts (SWRA) and SCISEARCH. Data were collected for 21 doctoral students working on their dissertations in the three fields of water resources. Principal findings included: 1) subject searching and citation searching each retrieved substantially equal number of documents; 2) total number of relevant documents for conceptual queries was larger than that for methodological queries, while there was a large variation among the three fields; 3) the average overlap was quite small, while citation searching yielded more unique documents than subject searching; 4) for conceptual queries, citation searching yielded a higher precision ratio than subject searching, while subject searching obtained a slightly higher precision ratio than citation searching for methodological queries ; and 5) citation searching was effective for both specific queries and broad queries if seed articles are well chosen, while subject searching only worked well for broad queries. It was further found that: 1) citation searching is not a subsidiary but a substantial retrieval method in water resources; 2) SWRA is effective for queries for engineering and SCISEARCH is appropriate for queries for natural science, while neither SWRA nor SCISEARCH work well for queries for social science; and 3) characteristics of queries affect retrieval results more than the characteristics of documents or the coverage of databases.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.4
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• pp.984-990
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• 2015

In the knowledge-based society, IT literacy and application of a person become a measure of personal competitiveness. As IT industry is of great important nationally, many countries are trying to make an effort to promote IT industry. In this sense, identification and fostering of the gifted children in IT become an important national task since, in IT industry, usually only a few prodigies have led whole IT industry. Currently gifted education aims for convergent gifted education according to government policy. The purpose of this paper is to investigate correlation of information subject and convergent subject for the gifted children in IT. For this purpose, the gifted children in IT who attended a gifted science education center attached to a university at Seoul Metropolitan Area are selected. Their grades during their the period of attendance are collected and analysed. The statistical results show that there is a meaningful correlation between information subject and convergent subject for the gifted children in IT. It means that the higher scores information subject is, the higher scores convergent subject is. The results can be used to make or change gifted curriculum and education contents for gifted IT education.

• Korean Journal of Computational Design and Engineering
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• v.18 no.4
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• pp.275-282
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• 2013

This paper proposes a method for human identification using teeth contours extracted from dental images that are captured from the frontal views of subjects each of who opens his or her mouth slightly. Each dental image has a black-colored region containing the subject's teeth contours which are usually different from subject to subject. This means that this black-colored region has bio-mimetic information useful for human identification. The basic idea of the method is to extract the upper and lower teeth contours from the dental image of each subject and to encode their geometric patterns using a back-propagation neural network model. After acquiring 400 teeth images form 10 university students, we used 300 images for the training data of the neural network model and 100 images for its verification. Experimental results have shown that the proposed neural network-based method can be used as an alternative solution for identification among a small group of humans with a low cost and simple setup.

• Advances in Energy Research
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• v.6 no.1
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• pp.17-33
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• 2019

This study aimed to observe trends in the literature on research, development, and innovation management in the energy sector, using performance assessment systems. The paper presented a bibliometric analysis of 40 studies on the subject. These materials come from ScienceDirect, Scopus and the Institute of Electrical and Electronics Engineers (IEEE) databases from 2006 to 2016. The results showed an increasing trend in the number of publications on the theme, showing the scientific community's interest in the subject. In addition, it was verified that the predominant language used to write the publications was English, the country that most published articles in the area was Brazil and most of the articles were produced through collaboration between researchers. It was found that the journal with the greatest number of publications on the subject was the Procedia - Social and Behavioral Sciences, while the Expert Systems with Applications journal presented the article with the greatest number of citations. This analysis allowed us to identify important points of the research and its future directions, in addition to enabling a better understanding of the world trend of the subject approached.

• Journal of Multimedia Information System
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• v.8 no.1
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• pp.1-10
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• 2021

Heart Rate is a crucial physiological parameter that provides basic information about the state of the human body in the cardiovascular system, as well as in medical diagnostics and fitness assessments. At present day, it has been demonstrated that facial video-based photoplethysmographic signal captured using a low-cost RGB camera is possible to retrieve remote heart rate. Traditional heart rate measurement is mostly obtained by direct contact with the human body, therefore, it can result inconvenient for long-term measurement due to the discomfort that it causes to the subject. In this paper, we propose a non-contact-based remote heart rate measuring approach of the subject which depends on the color intensity variation of the subject's facial skin. The proposed method is applied in two regions of the subject's face, forehead and cheeks. For this, three different algorithms are used to measure the heart rate. i.e., Fast Fourier Transform (FFT), Independent Component Analysis (ICA) and Principal Component Analysis (PCA). The average accuracy for the three algorithms utilizing the proposed method was 89.25% in both regions. It is also noteworthy that the FastICA algorithm showed a higher average accuracy of more than 92% in both regions. The proposed method obtained 1.94% higher average accuracy than the traditional method based on average color value.

• Journal of Engineering Education Research
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• v.21 no.1
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• pp.37-43
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• 2018

The purpose of this study is to investigate the effects of peer tutoring and feedback on academic learning in university mathematics. We compared subject satisfaction and academic achievement between the test group and the control group. We classified the test group(82 participants) and the control group(134 non-participants) and then applied peer tutoring and feedback to the test group. The rest of the environment was the same except for participation in the program. According to results, it was confirmed that the subject satisfaction were significantly higher(significance level .05) in the test group, where the subject satisfaction were learning objectives and expectation, learning satisfaction, and learning effect. Furthermore, in the change of academic achievement, the rate of decrease was lower and the rate of increase was higher in the test group than the control group. The satisfaction of participants was 4.33(Likert scale 5), and this trend tended to be same regardless of gender, high school course, or admission process.