• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.870-874
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• 2007

Golf ball spin rate after impact with club is created by the contact force, which is greatly influenced by ball and club mass, material, impact speed, and club loft angle. Previous studies showed that the contact force is determined as the resultant force of the reaction forces normal and tangential to the club face at the contact point. The normal force causes the compression and restitution of the ball, and the tangential force creates the spin. Especially, the tangential force takes either positive or negative values as the ball rolls and slides along the club face during impact. Although the positive and negative tangential forces are known to create and reduce the back spin rate, respectively, the mechanism of ball spin creation has not yet been discussed in detail. It is shown in this work that the linear impulse of the tangential force is directly related to generation of back spin rate of golf ball. The linear impulse can be calculated from the tangential force, which depends upon many factors such as ball and club mass, material, impact speed, and club loft angle. In this research, the influence of the contact force between golf club and ball is investigated to analyze the mechanism of impact. For this purpose, the contact force and the contact time at impact between golf club head and ball are computed using FEM.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.17 no.11
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• pp.1127-1132
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• 2007

Golf ball spin rate after impact with club is created by the contact force, which is greatly influenced by ball and club mass, material, impact speed, and club loft angle. Previous studies showed that the contact force is determined as the resultant force of the reaction forces normal and tangential to the club face at the contact point. The normal force causes the compression and restitution of the ball, and the tangential force creates the spin. Especially, the tangential force takes either positive or negative values as the ball rolls and slides along the club face during impact. Although the positive and negative tangential forces are known to create and reduce the back spin rate, respectively, the mechanism of ball spin creation has not yet been discussed in detail. It is shown in this work that the linear impulse of the tangential force is directly related to generation of back spin rate of golf ball. The linear impulse can be calculated from the tangential force, which depends upon many factors such as ball and club mass, material, impact speed, and club loft angle. In this research, the influence of the contact force between golf club and ball is investigated to analyze the mechanism of impact. For this purpose, the contact force and the contact time at impact between golf club head and ball are computed using FEM.

• Journal of Digital Convergence
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• v.11 no.3
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• pp.49-57
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• 2013

This study examined influence of strengths of family life and satisfaction with school life on adolescent psychological well-being, particularly targeting at high school students in the rapidly changing IT-based society. In order to investigate influence of factors related to home and school as the main living spaces on improving adolescent psychological well-being, a survey of 251 students at K academic high school in Busan was conducted and then multiple regression analysis was carried out. Firstly, the analysis showed that adolescents' sharing time at home could make a positive impact on their positive interpersonal relationships. It also showed that family bonds could have a positive impact on adolescents' positive interpersonal relationships, the goal of life, and personal growth, and thus satisfaction in communication at home was a factor that could be helpful to environmental control. Secondly, it indicated that adolescents' satisfaction with school life was a factor that had a positive impact on self-acceptance, environmental control, and the goal of life among the sub-factors of psychological well-being. It turned out that peer relationships could have a positive impact on positive interpersonal relationships, likewise school lessons and peer relationships could have a positive impact on autonomy. According to the results of analysis, factors related to strengths of family life and satisfaction with school life could affect adolescent psychological well-being. Therefore, these findings can be applied to establishing major youth policy.

• Journal of Korean Neurosurgical Society
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• v.38 no.1
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• pp.41-46
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• 2005

Objective : A study of the histopathologic and neurobehavioral correlates of cortical impact injury produced by increasing impact velocity using the controlled cortical impact[CCI] injury model is studied. Methods : Twenty-four Sprague-Dawley rats [$200{\sim}250g$] were given CCI injury using a pneumatically driven piston. Effect of impact velocity on a 3mm deformation was assessed at 2.5m/sec [n=6], 3.0m/sec [n=6], 3.5m/sec [n=6], and no injury [n=6]. After postoperative 24hours the rats were evaluated using several neurobehavioral tests including the rotarod test, beam-balance performance, and postural reflex test. Contusion volume and histopathologic findings were evaluated for each of the impact velocities. Results : On the rota rod test, all the injured rats exhibited a significant difference compared to the sham-operated rats and increased velocity correlated with increased deficit [p<0.001]. Contusion volume increased with increasing impact velocity. For the 2.5, 3.0, and 3.5m/sec groups, injured volumes were $18.8{\pm}2.3mm^3$, $26.8{\pm}3.1mm^3$, and $32.5{\pm}3.5mm^3$, respectively. In addition, neuronal loss in the hippocampal sub-region increased with increasing impact velocity. In the TUNEL staining, all the injured groups exhibited definitely positive cells at pericontusional area. However, there were no significant differences in the number of positive cells among the injured groups. Conclusion : Cortical impact velocity is a critical parameter in producing cortical contusion. Severity of cortical injury is proportional to increasing impact velocity of cortical injury.

• Korean Journal of Applied Biomechanics
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• v.27 no.4
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• pp.263-268
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• 2017

Objective: The purpose of this study was to show differences in impact variables between treadmills with (treadmills B, C, and D) and treadmills without a shock-absorbing function (treadmill A) to propose the development of a treadmill with improved or added shock-absorbing function to reduce impact shock. Method: Thirteen male students in their twenties who had habitual rear foot strike during running ran on four treadmills at 2.67 m/sec while ankle and neck acceleration data were collected. The magnitude of the ankle and neck acceleration peaks and peak positive ankle acceleration were calculated. The power spectral density of each signal was calculated to transform the ankle and neck accelerations in the frequency domain. Results: The peak positive ankle acceleration on treadmill B was significantly lesser than that on treadmills A and D, and that on treadmill C was significantly less than that on treadmill A (p < .01). Peak positive neck acceleration was not statistically different between the treadmills. The frequencies of the peak power of the ankle and neck acceleration signal within the lower and higher frequency ranges were not statistically different between the treadmills. The signal power magnitude of the ankle in higher frequency ranges on treadmill B was significantly less than that on treadmills A, C, and D (p < .01). The signal power magnitude of the ankle in higher frequency ranges was not statistically different between the treadmills. The signal power magnitudes of the neck acceleration signal within the lower and higher frequency ranges were not statistically significantly different between the treadmills. Conclusion: Our results indicate that the shock-absorbing function of a treadmill plays a role in reducing impact shock. Therefore, in future treadmill development, shock-absorbing function should be improved or incorporated to reduce impact shock to the body.

• Quality Improvement in Health Care
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• v.23 no.1
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• pp.69-90
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• 2017

Purpose: The purpose of this study was to analyze the impact of healthcare accreditation and to provide empirical evidence to validate positive effectiveness. Methods:Six electronic databases (KERIS, KoreaMed, NDSL, Ovid-medline, Embase, Cochrane library) were accessed in May 2016. Keywords used were 'accreditation' and 'Joint Commission on Accreditation of Healthcare Organization (JCAHO)'. Of the initially identified 3,008 articles, 60 studies on healthcare accreditation were selected based on inclusion criteria that are hospital accreditation, accreditation by disease and clinical center accreditation. These were retrieved and analyzed. Result: The 60 study results were on the impact of healthcare accreditation. Results were classified into four perspectives of Balanced Score Card (Financial, Customer, Internal Process, Learning & Growth). In internal process perspective, results revealed that healthcare accreditation has made a positive impact on "care process and procedure". In learning & growth perspective, healthcare accreditation has made a positive influence on "leadership", "organizational cultures" and "change mechanisms". However, it revealed that healthcare accreditation does not directly affect financial performance. It is also difficult to reach a definitive conclusion that healthcare accreditation programs affect patient satisfaction of customer and clinical outcome of the internal process. Conclusion: Healthcare accreditation programs provide positive impact on change of care process and building communication-oriented hospital culture. However, more rigorous and diverse research is needed on financial effects and clinical outcomes of healthcare accreditation.

• Journal of the Korean Operations Research and Management Science Society
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• v.35 no.2
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• pp.89-114
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• 2010

This study empirically investigated the effects of the target costing system as well as information technology(IT) infrastructure on the knowledge management processes(i.e., socialization, externalization, combination and internalization) and the performance of a firm. This study also examined an impact of the social capital(i.e., inter-departmental communication, trust, cooperation and integration) on the adoption and development of the target costing and the IT infrastructure. The results of this study showed that inter-departmental communication, trust and integration have a significant positive impact on the adoption of the target costing. It was also found that the effects of inter-departmental communication and integration on the development of storage and transfer infrastructure are significant and positive. However, in the adoption of search infrastructure, only the impact of inter-departmental integration was significant. The results of regression analyses presented that the target costing has significant influence on the four processes of knowledge management. It was also observed that the effects of storage and transfer infrastructure on combination are significant and positive. In search infrastructure, the impact on combination and internalization was significant. According to the results of this study, it was found that when the adoption level of the target costing is high, search infrastructure mainly affects the three processes(i.e., socialization, combination and internalization). However, under a low adoption level of the target costing, the impact of storage and transfer infrastructure on the whole processes was significant and positive. Thus, it is assumed that storage and transfer infrastructure complements a low level of the target costing adoption through the active transfer and sharing of explicit and tacit knowledge.

• Journal of Convergence for Information Technology
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• v.8 no.4
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• pp.1-8
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• 2018

The objective of study is to investigate Oral health impact profile, Self-esteem and Body image of orthodontic patients and to use it as basic data in consultation and education for orthodontic patients. A self-reported questionnaire was filled out Orthodontic patients in Seoul, Daejeon and Cheongju from March 1 to March 30, 2018. There was a positive correlation between Oral health impact profile and Self-esteem, and there was a positive correlation with Body image. Self-esteem and Body image showed positive correlation. The general characteristics of orthodontic patients are related to oral health impact profile, self-esteem and body image. So as to improve and experience positive body image and self-esteem changes while providing correct information, searching and accepting the present body image.

• Culinary science and hospitality research
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• v.22 no.7
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• pp.222-234
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• 2016

This study measures the impact of restaurant franchise brand equity and brand value on consumer loyalty and customer satisfaction. The purpose of this study was to investigate the relationship between variables based on previous studies. The survey for this present study was conducted from consumers who visited in a franchise restaurant within three months. in Seoul and the metropolitan area. Research revealed that brand equity and value of the franchise restaurant appeared to have a positive impact on customer loyalty, and then consumer loyalty exhibiting a positive impact on consumer satisfaction. In addition, brand equity and value of the franchise restaurant showed a positive impact on customer loyalty.

• Journal of Distribution Science
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• v.18 no.10
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• pp.25-38
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• 2020

Purpose: Traditional markets have served as important locations for social-cultural and economic activities. It is a hub of economic transactions and where people gather and exchange information and goods, while also serving as the center of social activities, including commercial exchanges. Accordingly, this study aimed to contribute to the studies on the perceived value in traditional markets for customers in different aspects. Research design, data, and methodology: To analyze the proposed model, data was collected from 456 respondents and analyzed with SPSS 21.0 and AMOS 21.0. The data was analyzed with structural equation modeling (SEM) using path analysis. Results: According to the results of the analysis, the perceived value comprises utilitarian value, emotional value, economic value, and social value, all of which had a positive impact on attitude. Emotional value and social value had a positive impact on subjective norms, while utilitarian value and economic value did not have an impact on subjective norms. Also, attitudes and subjective norms were found to have a positive impact on behavioral intention. Conclusions: Through this study, the value that the traditional markets need to provide to consumers have been identified. Traditional markets should develop into places that can provide value for their consumers.