• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.5
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• pp.561-568
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• 2020

A performance analysis was conducted according to changes in inflow velocity and the tip speed ratio of a portable horizontal-axis hydro turbine that can be used for marine leisure sports and outdoor activities by using the commercial computational fluid dynamics software ANSYS CFX. By using the analysis result and flow field analysis, the design was reviewed and the performance of the device was confirmed. In addition, data necessary to improve the performance of the hydro turbine were acquired by performing an additional performance analysis according to the variable blade pitch angle. The results among the numerical analysis cases show that the highest performance at all inflow velocities and blade pitch angles if achieved at a tip speed ratio of 4. The output power was found to be 30 W even under some conditions below the design flow rate. Among the numerical analysis cases, the highest output power (~ 85 W) and power coefficient (~ 0.30) were observed at an inlet flow rate of 1.5 m/s, a blade pitch angle of 3°, and a tip speed ratio of 4.

• Korean Journal of Applied Biomechanics
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• v.18 no.4
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• pp.1-19
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• 2008

This research is to analyze the force on landing 3 Type of Halfpipe Curves(Ellipse, Circle, Brachistochrone) based on the mechanical calculation of normal force on a sloping surface. Jumping off a platform on a bard horizontal surface, the flexing of the legs, the softness of the snow, the angle of the landing surface, initial velocity and the forward motion of the snowboarder can contribute to reducing the force on landing. But halfpipe is significantly determined by the curvature of surface. It is definitely verified that the Brachistochrone curve is more safety than others. However currently using the Ellipse curve is mostly safe too. If we consider the efficiency of construction, we can easily think there is no use of another curves except normal ellipse curved halfpipe. It would better that geometrically verity curved halfpipe should be designed for improving fluent skills to snowboarders. This methode of research can be a model of scientifical research on sports safety how can sportsman reduce critical injury by designing optimal halfpipe facilities and manual.

• The Journal of the Korea Contents Association
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• v.10 no.3
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• pp.337-346
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• 2010

The purpose of this study is to explore how security science graduates in casinos are socialized into the workplace. Participants for this study were seven security guards who work for two of three casinos for foreign customers in the city of Seoul. All the participants majored in the security science in colleges. They had 1 to 5 years of work experience. Their main job responsibilities were deterrent to crimes and watch for impending danger in the casinos. A variety of qualitative data collection techniques for this study included formal and informal interviews, stimulated-recall interview, observations, and field notes. Analytic induction and constant comparison were utilized to analyze data. Triangulating and member checks were employed to enhance trustworthiness. The findings of this study were as follow: Firstly, In acculturation, sports experience and media attraction were revealed as factors. Secondly, In professional socialization, college education and senior students in the program were found. Lastly, organizational socialization, Difficulty of relationship, lack of risk management training, lack of team cohesion, pride himself as a security guard, and unclear evaluation system. In conclusion, a variety of influential factors appeared through his occupational socialization even though there were negative and positive factors.

• Korean Security Journal
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• no.17
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• pp.15-31
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• 2008

This study aims to analysis and measure on the private security for the academic directivity and security industry for the market directivity in Korea. For this study we compare and analysis the curriculum of 15 universities in Korea and the papers which were published on "Korean Security Science Review" that is a report in a professional private security. In conclusion, 269 subjects are used as instructional materials in 15 universities, thus 103 subjects for the private security and 60 for the leisure sports and first-aid treatment, 46 for the social science, 30 for the martial arts and shooting, 16 for the secretary affairs, 14 for the foreign languages. Regarding scientistic papers, 45.7% of papers for the private security of all and 14.6% for the public security, 14.6% for the criminal, and 11.6% for the terror etc. But there are any papers for the facilities guard or security in spite of the facilities guard is pivotal role in this field. The facilities guard or security, or maybe house detective, holds 80.5% of the private security market and it is important role in this industry in Korea. Besides, considering development of private security, the security market makeup the body-guard field hold 12.2%, prevention security system by censor hold 4.1%. So, this statistics show that the facilities guard lead practically the private security industry in this field, but there are any subjects for the education and any research for the paper. Thus some modification on the universities curriculum is required, also needs activity research in the facilities guard field for the development private security.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.7
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• pp.945-952
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• 2018

Recently, bass fishing has become a marine leisure sport in Korea. There are 4 major fishing associations in Korea, and each association holds 10-15 tournaments each year. However, supply of 17 ft bass boats, which are preferred in leagues, depends 100 % on imports. In this study, we have derived the main specifications to develop the initial hull forms of a 18.5ft bass boat through statistical analysis based on mothership data. In addition, CFD numerical analysis was carried out according to deadrise angle and longitudinal center of gravity, which strongly influenced the resistance and planing performance. For numerical analysis, design speed was set to $Fn=3.284 (Re=9.858{\times}10^7)$, the deadrise angle was set from 12 to $20^{\circ}$, and the longitudinal center of gravity was set in the range of 0 to $8%L_{wL}$ from the center of buoyancy to the stern. Based on the numerical results, we first set the range of these factors by resistance performance and immersion keel length. Furthermore, using a correlation graph of Savitsky's Drag-Lift ratio, we derived the deadrise angle ($14-16^{\circ}$) and longitudinal center of gravity ($4-6%L_{wL}$).

• Journal of Convergence for Information Technology
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• v.9 no.8
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• pp.140-147
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• 2019

The purpose of this study is to find biomechanical parameters for optimal shoes production through an ergonomic usability assessment of five existing types of shoes preferred by B-BOY. Ten experts and ten non-experts participated in the experiment, and 12 infrared cameras (Qualis, Oqus), force plate (Kistler, 9286AA) and foot pressure plate (Zebris Gmbh, Zebris PDM-System) were used to obtain the data. The results of the study are as follows. First, P shoes with a friction coefficient of 0.38 and a free moment of 0.32 N/m/kg are desirable in terms of traction capability and safety. Second, on the cushion, it was found that the N shoes 2.51 N, sec/kg and non-expert, and 2.86 N and sec/kg were suitable. Third, it is deemed appropriate for C shoes with a forefoot average pressure of 10.11 KPa (right), 10.05 KPa (left), and V shoes with a rearfoot average pressure of 8.4 KPa (right) and 8.36 KPa (left). In conclusion, the combination of the structure and material of V shoes should be developed for traction and stability, N shoes for cushion, and walking balance for C and V shoes.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.4
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• pp.477-487
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• 2022

This study suggests a plan for revitalizing return-to-farming / fishing villages through the marine leisure industry by analyzing the practical problems faced by young and older adults who have returned to the marine leisure field. A case study was conducted to identify the problems faced by those returning to marine leisure, and to determine the measures for revitalizing return-to-farming / fishing villages. Interview participants were those returning to marine leisure and experts in related fields. The problems identified include the exclusive culture of fishing villages, difficulty in raising initial investment funds, and lack of marine leisure education programs for return-to-farming / fishing villages. The proposals to solve these problems and revitalize return-to-farming / fishing villages through the marine leisure industry include the introduction of an incentive system to mitigate barriers to entry; establishment of a matching system; use of idle land in fishing villages to promote return-to-farming / fishing villages; introduction of a consignment management system after the pre-investment of the fishing villages; and establishment of an education program, including in the fisheries field, and infrastructure for return-to-farming / fishing villages for marine leisure.

• 한국체육학회지인문사회과학편
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• v.55 no.2
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• pp.35-46
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• 2016

This study aims to observe the operation aspect of physical education during before class and further, to search for the utmost improvement direction using IPA (Importance-Performance Analysis). 500 middle & high school students have chosen through a purposeful sampling method, and 430 was used for analysis. The results were as follows. The quadrant I is "the keep up the good work" part. And the quadrant I includes "de-stress", "the pleasure of school life", "improvement in performance", "peer relationship", "help for P.E.", "health promotion", "sport facility surroundings", "rules", "teacher leadership", "passionate coaching", "fair coaching", "improvement in exercise ability", "understanding P.E." The quadrant II is "the concentrate here" part. And the quadrant II includes "develop talent", "excercise time", "safety management for exercise facility", "new sports event", "consider needs and interests", "consider level" "consider gender". The quadrant III is "the low priority" part. And the quadrant III includes "change of personality", "ability to do various sports event", "develope thinking ability". "communication with peer" "an intelligible explanation" In order to improve the quality of before classes, first, "safety connected program" second, "emotional and intellectual development program", third, "divided classes per level and gender", and the last, "professional manpower for developing the quality of class" are needed.

• The Journal of the Convergence on Culture Technology
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• v.10 no.3
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• pp.209-217
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• 2024

The purpose of this study is to explore development plans by analyzing social interests and perceptions of jiu-jitsu using big data analysis. Network analysis, centrality analysis, and CONCOR analysis were conducted by collecting data for the last 10 years of major domestic portal sites. First, 'judo' was found to be the most important related word in network analysis, and 'judo' was also an important word in the analysis of dgree centrality. In the closeness centrality analysis, "defender" was the most important word, and "sports" was the most important word in betweenness centrality. Finally, as a result of CONCOR analysis, four clusters (related sports and marketing, jiu-jitsu competitions, belt test, supplies and expenses) were formed. As a conclusion of the study, first, words such as 'judo', 'exercise', 'competition', 'dobok', 'gym', and 'graduation' should be actively used to promote jiu-jitsu.As a conclusion of the study, first, words such as 'judo', 'exercise', 'contest', 'dobok', 'gym', and 'graduation' should be actively used to promote jiu-jitsu. Second, it is necessary to share information on training costs through various routes, to make awareness of the graduation process or method common, and to develop safety products and create a safe training culture. Third, it is necessary to find ways to continuously increase the influx of new trainees by attracting steady competitions.

• The Korean Journal of Air & Space Law and Policy
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• v.33 no.1
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• pp.175-204
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• 2018

Recently, the aviation leisure business has been legislated, and related industries have become active base with increasing the light sports aircraft within the legislation system. However, in the light sports aircraft safety problem, it is often mentioned that the flight is in violation of the regulations, the lack of safety consciousness of the operator and lack of ability, and the personal operators have a risk of accident of light aircraft such as insufficient safety management and poor maintenance. At present, the maintenance of light sports aircraft is carried out by the A & P mechanic in accordance with the relevant laws and regulations, but it is difficult to say that it is equipped with qualification and expertise. It is not a legal issue to undertake light sports aircraft maintenance work on the regulation system. However, the problem of reliability and appropriateness is constantly being raised because airplanes, light sports aircraft, and ultra-light vehicle are classified and serviced in a legal method. Although legal and institutional frameworks for light sports aircraft are separated, much of it is stipulated in the aviation law provisions. Light sports aircraft maintenance work also follows the current aircraft maintenance system. In the United States, Europe, and Australia where General Aviation developed, legal and institutional devices related to maintenance of light aircraft were introduced, and specialized maintenance tasks are covered in the light aircraft mechanics system. As a result of analysis of domestic and foreign laws and regulations, it is necessary to introduce the qualification system for maintenance of light aircraft. In advanced aviation countries such as the United States, Europe, and Australia, a light sports aircraft repairman system is installed to perform safety management. This is to cope with changes in the operating environment of the new light sports aircraft. This study does not suggest the need for a light aircraft repairman system. From the viewpoint of the legal system, the examination of the relevant laws and regulations revealed that the supplementary part of the system is necessary. It is also require that the necessity of introduction is raised in comparison with overseas cases. Based on these results, it is necessary to introduce the system into the light aircraft repairman system, and suggestions for how to improve it are suggested.