• Journal of the Korean Physical Society
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• 제73권9호
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• pp.1269-1278
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• 2018

Using the thawed Gaussian wave packets [E. J. Heller, J. Chem. Phys. 62, 1544 (1975)] and the adaptive reinitialization technique employing the frame operator [L. M. Andersson et al., J. Phys. A: Math. Gen. 35, 7787 (2002)], a trajectory-based Gaussian wave packet method is introduced that can be applied to scattering and time-dependent problems. This method does not require either the numerical multidimensional integrals for potential operators or the inversion of nearly-singular matrices representing the overlap of overcomplete Gaussian basis functions. We demonstrate a possibility that the method can be a promising candidate for the time-dependent $Schr{\ddot{o}}dinger$ equation solver by applying to tunneling, high-order harmonic generation, and above-threshold ionization problems in one-dimensional model systems. Although the efficiency of the method is confirmed in one-dimensional systems, it can be easily extended to higher dimensional systems.

• Journal of the Korean Physical Society
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• 제73권10호
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• pp.1410-1419
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• 2018

A skier's motion was analyzed by a simple model consist of point mass m and a single rod connected to a single ski plate. We studied the conditions for the stable ski turn as functions of the linear velocity and the radius of the turn. The solutions for the stable ski turn in our model do not require any extra skier's movement to complete a stable circular turn. The solution may then give the skier the most comfortable skiing method without any active movement to control the ski. The generalized force supporting the point mass from the ski plate was calculated. We obtained the force from the ground (rebound force) without any geometrical structure of the ski plate. Adding an active movement to the direction of the ski plate, the conditions for the stable ski turn were also analyzed. Our result gives some insight for the skier who wants to develop technique.

• 산업경영시스템학회지
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• 제18권35호
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• pp.71-78
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• 1995

The recent increase of old people will potentially bring about a grave socio-economical effect. Thus, the system of reemploying them should be effectively pursued. Their reemployment, along with the rearrangement of work places and the development of jobs meeting their physical, mental and psychological characteristics, will help keep up their productivity and safety as well. The change of physical functions arising from age increase can be blown from a comparison with those of young people. This study concerning the aged people's speed of judgment and limbs movement in comparison with young counterparts, I hope, will aid in designing the old population's proper jobs and work places.

• Journal of Information Processing Systems
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• 제15권3호
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• pp.478-491
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• 2019

This work develops a monitoring system for the population with health concerns. A belt integrated with an on-body circuit and sensors measures a wearer's selected vital signals. The electrocardiogram sensors monitor heart conditions and an accelerometer assesses the level of physical activity. Sensed signals are transmitted to the circuit module through digital yarns and are forwarded to a mobile device via Bluetooth. An interactive application, installed on the mobile device, is used to process the received signals and provide users with real-time feedback about their status. Persuasive functions are designed and implemented in the interactive application to encourage users' physical activity. Two signal processing algorithms are developed to analyze the data regarding heart and activity. A user study is conducted to evaluate the performance and usability of the developed system.

• Journal of Acupuncture Research
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• 제36권2호
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• pp.88-91
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• 2019

Background: The intelligent tissue hypothesis on how acupuncture works, states that real-time organ states are reflected in the tissue at an organ's related acupuncture points (acupoints). Any such changes in the tissue would produce corresponding changes in the impedance at those locations. Methods: To test this hypothesis in relation to the lungs, the impedance at key lung-related acupoints was monitored in real time while the patient breathed normally, then breathed deeply, then quickly, then held his breath. Results: When breathing deeply this produced a notable decrease in the impedance at 1 acupoint, while breathing quickly produced a decrease at another acupoint, suggesting that these different functions taxed different aspects of the lungs, which was then reflected at different acupoints. The impedance at all the acupoints also contained low-amplitude waves that reflected the base rate of the respiration pacesetter, and the amplitude of these waves also varied to reflect different real-time states in the lungs. Conclusion: These real-time impedance patterns suggested that corresponding physical patterns were present in the tissue at these acupoints, and these physical patterns mirrored the real-time variations in function strength of the related organ (the lungs). These results were consistent with the hypothesis.

• 대한치료과학회지
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• 제10권2호
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• pp.13-20
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• 2018

Objective: To investigate the effects of a brain fitness exercise on the cognitive function of patients with dementia. Method: Forty-six elderly adults diagnosed with dementia were randomly allocated to the study or control group (n=23 per group). The study and control groups performed a brain fitness and regular exercise, respectively, for 40 minutes a day, three times a week for four weeks. We examined cognitive capacity using MMSE-K, cognitive strength, judgment time, and mental workload scores before and after intervention. Results: The study group showed significant improvements in all variables. In addition, the control group showed a significant improvement in brain stress. We found that there was a significant improvement in the study group when compared with the control group in all variables. Conclusion: Based on these results, we suggest that brain fitness exercise would be effective in improving cognitive functions of dementia patients.

• Journal of the Korean Physical Society
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• 제73권12호
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• pp.1800-1807
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• 2018

In this paper, we study the gravitational perturbation of traversable wormhole spacetime, especially the Morris-Thorne wormhole spacetime, by using the linearized theory of gravity. We restrict our interest to the first order term and ignore the higher order terms. We assume that the perturbation is axisymmetric. We also assume that the time dependence follows the Fourier decomposition and the angular dependence is expressed in terms of the Legendre functions. As a result, we derive the gravitational perturbation equation of traversable wormhole in terms of a single linear second-order differential equation. As a consequence, we could analyze the unstability of the spacetime with the effective potentials. Furthermore, we consider the interaction between the external gravitational perturbation and the exotic matter, constituting traversable wormholes and its effect on the stability of traversable wormholes.

• International Journal of Contents
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• 제18권1호
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• pp.98-104
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• 2022

With Unity creating footage is possible by using 3D motion, 2D motion, particular, and sound. Even post-production video editing is possible by combining the footage. In particular, Cinemachine, a suite of camera tools for Unity, that greatly affects screen layout and the flow of video images, can implement most of the functions of a physical camera. Visual aesthetics can be achieved through it. However, as it is a part of a game engine. Thus, the understanding of the game engine should come first. Also doubts may arise as to how similar it is to a physical camera. Accordingly, the purpose of this study is to examine the advantages and cautions of virtual cameras in Cinemachine, and explore the potential for development by implementing storytelling directly.

• 한국융합학회논문지
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• 제12권3호
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• pp.325-339
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• 2021

연구의 목적은 문헌고찰을 통해 스포츠 관련 인지기능과 이를 효과적으로 측정할 수 있는 검사도구를 제안하고, 스포츠 지능 연구의 기초를 마련하는 것이다. 문헌고찰은 체계적 문헌고찰과 메타분석 지침인 PRISMA 연구법에 근거하여 수행되었다. 게재년도 2008-2020년으로 검색기준 설정 후, 키워드를 통해 검색된 총 429편 중 본 연구의 문헌선택 기준을 충족한 45편이 최종 분석되었다. 고찰된 논문 결과를 요약하면, 선수들은 비선수보다 특정 인지기능이 우수하고, 스포츠 전문성이 높을수록 해당 인지기능이 더 높았으며, 종목에 따라 인지기능에 차이가 있는 것으로 나타났다. 45편에 대한 종합적 분석결과, 스포츠 수행과 관련된 주요 인지기능은 실행기능(억제능력, 인지유연성), 정보처리속도, 공간능력, 주의력으로 요약된다. 각 인지기능 측정을 위한 검사도구로 억제능력은 정지신호과제, 인지유연성은 설계유연성검사, 정보처리는 단순반응검사와 선택반응검사, 공간능력은 심적회전검사, 주의력은 주의연합검사가 적절하다.

• 한국학교ㆍ지역보건교육학회지
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• 제4권
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• pp.79-95
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• 2003

This dissertation aims to analyze various safety accidents taking place during physical education class according to physical education teacher's value orientation, to identify teacher's value orientation that can minimize safety accidents, and to provide basic materials for safe and smooth class management. For this purpose, data have been collected from 261 physical education teachers at some middle and high schools in G City in Kyung-Ki Province and Busan Metropolitan City. The materials were treated as follows: The variables on demographic characteristics of physical education teachers are determined by t-test ; The analysis of one-way ANOVA and relationship between value orientation and safety accident prevention activities was conducted through Pearson's linear correlation analysis and multiple regression; The analysis of the relationship between value orientation and actual conditions of safety accidents was conducted through logistic regression. First, there is almost no awareness difference of physical education teachers' value orientation according to demographical variables. The value orientation physical education teachers consider to be the most important is, however, mainly 'mastery of disciplinary lesson.' There is a statistically significant difference in safety accident prevention activities according to demographical variables. Teachers' focuses in class contents showed a significant difference according to teaching experience and working area, while the dependency on facility has a significant difference according to teaching experience and school type. Second, there is no correlation between physical education teacher's value orientation and safety accident prevention activities because there is virtually no statistically significant difference between them. It means that safety accident prevention activities are not related with on which teachers place emphasis among mastery of disciplinary lesson, social reconstruction, self-realization, ecological integration and value orientation on learning process. Third, the analysis of safety accident prevention activities according to physical education teachers' value orientation revealed that the lower value orientation in social reconstruction is, the more safety accidents teachers experience. It is also found that crashes among students, ball games and leg injuries are inter-related with social reconstruction in value orientation, over-motivation and unskilled motor function ; athletic sports with value orientation on learning process and safety prevention training ; unskilled motor functions with value orientation in ecological integration and disobedience to teacher's directions ; winter accidents with mastery of disciplinary lesson in value orientation. In conclusion, the research indicates that physical education teacher's value orientation according to demographical variables didn't show any significant difference, while one according to safety accident prevention activities showed significant difference. Besides, physical education teachers' value orientation is not related to safety accident prevention activities, but the relationship between value orientation and actual conditions of safety accidents showed correlations according to each variable. Especially, teachers with lower value orientation in social reconstruction experienced more safety accidents. Therefore, physical education teachers can manage physical education class more safely with more emphasis on value orientation in social reconstruction.