• 한국군사과학기술학회지
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• 제15권4호
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• pp.359-365
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• 2012

In the soft recoil system, the recoiling parts are initially accelerated to the forward direction. These parts are returned to original position by the firing with intial acceleration speed. The latch of the soft recoil system keeps the high impact load when the recoil parts were recuperated to the forward direction. In this study, the latch of soft recoil system using the ADAMS program was analyzed. The optimal operation parameters were found that max. angle and expansion length of latch was $50^{\circ}$, 180 mm respectively. Dynamic structural analyses of model cases were performed using finite element model. The max. stress and deflection of latch was 230 MPa and 0.45 mm respectively.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 1997년도 International Symposium on Fire Science and Technology
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• pp.112-119
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• 1997

The modelling of carbon substances obtaining, for instance, carbon fibers which have high fire resistance, has been realized on the example of the polyacrylonitrile pyrolysis modelling. The pyrolysis is considered as a double step process when the formation of a liquid phase and the oxidation of substance are excluded. Three main reactions are considered: a) with the evolution of ammonia; b) with the evolution of hydrogen cyanide; c) with the evolution of hydrogen. Reactions b) and c) are sequential, and a) and b) are parallel. The problem is formulated as one-dimensional. The equations of energy, masses or concentrations, porosity and thermal conductivity are proposed. The mathematical model of the carbonization process is designed using tile kinetic characteristics of the above reactions and the thermodynamic parameters of reagents and products in these reactions. The equations received are calculated by Runge-Cutta method and by Adams method of the fourth order accuracy.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집 특별세미나,특별/일반세션
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• pp.473-479
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• 2009

Dynamic analysis is necessary for the High-Speed Railway vehicle which aims to run on max 400km/h. Especially, dynamic simulation using CAE(Computer Aided Engineering) can help to reduce the time of development of the High-Speed Railway vehicles. Also, it helps to reduce prices and improve the quality such as safety, stability and ride. There are many dynamic software for a railway vehicle, such as Vampire and ADAMS-Rail. There are limitations for each software and difficulties to analyze overall dynamics for entire railway system. To overcome these limitations, in this study, a program which can simulate entire railway vehicles was developed. This program is easy to use because it was developed using C++, which is object-oriented programming language. In addition, the basic platform for the development of dynamic solver is prepared using the nodal, modal coordinate system with a wheel-rail contact module. Rigid, flexible and large deformable body systems can be modeled by a user according to the characteristic of a desired system. Its reliability is verified by comparison with a commercial analysis program.

• PNF and Movement
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• 제3권1호
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• pp.55-66
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• 2005

목적 : 본 연구는 경미한 경부 통증을 가진 대상자의 경부 운동감각과 경부 통증과 기능에 대하여 조사하였다. 방법 : 본 연구의 대상자는 자발적으로 참여한 81명의 (나이 18-30세, 평균 23.2) 건강한 대학생으로 구성되었으며, 측정은 경부운동감각과 통증 및 기능에 대하여 측정하였다. 경부운동감각은 편안히 앉은 자세에서, 경부 후인과 좌우 회전의 중간 관절 범위에서 대상자의 두부에 착용하지 않는 기구를 사용하여 측정하였다. 경부 통증과 기능은 가장 흔히 쓰이는 4가지 설문지를 한국어로 번역하고 문화적으로 적응하는 과정을 거쳐 사용하였다. 결과 : 대상자들을 경부 통증 빈도에 따라 세 집단으로 (통증 없음, 월별, 주별) 구분하였다. 각 집단간에는 4가지 설문지로 조사한 경부통증과 기능에는 차이를 보이지 않았으나, 경부운동감각은 통증 빈도가 높을수록 더 민감하게 나타났다 결론 : 경부 운동감각은 편안히 앉은 자세에서 경부 후인과 좌 우회전의 중간 관절범위에서 측정하였으며, 경미한 경부 통증 빈도가 높을수록 경부 운동감각은 더 민감하게 나타났다.

• 한국기계기술학회지
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• 제20권6호
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• pp.947-956
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• 2018

This research has been conducted to design upright parts of hand-made vehicles with the purpose of reducing material and machining cost while ensuring structural safety. Aluminum knuckles were modelled with three parts in order to enhance design flexibility as well as to reduce CNC machining cost. A vehicle model was constructed in CAD program and simulated in ADAMS View in order to estimate joint forces developing during 20 degree step steering condition at 60km/h. The joint forces obtained in the vehicle dynamics simulation were used for the structural analysis in ANSYS and dimensions of knuckle parts were adjusted until the lowest safety factor reached 2.0. The weight of knuckle decreased by 50% compared to the previous version that was designed without the structural analysis. The overall manufacturing cost decreased by 33% due to the reduction in the material as well as the CNC machining effort.

• Nuclear Engineering and Technology
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• 제53권8호
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• pp.2708-2715
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• 2021

The Multi-Purpose Overload Robot (CMOR) is a key subsystem of China Fusion Engineering Test Reactor (CFETR) remote handling system. Due to the long cantilever and large loads of the CMOR, it has a large rigid-flexible coupling deformation that results in a poor position accuracy of the end-effector. In this study, based on the Levenberg-Marquardt algorithm, the spatial grid, and the linearized variable load principle, a variable parameter compensation model was designed to identify the parameters of the CMOR's kinematics models under different loads and at different poses so as to improve the trajectory tracking accuracy. Finally, through Adams-MATLAB/Simulink, the trajectory tracking accuracy of the CMOR's rigid-flexible coupling model was analyzed, and the end position error exceeded 0.1 m. After the variable parameter compensation model, the average position error of the end-effector became less than 0.02 m, which provides a reference for CMOR error compensation.

• 융복합기술연구소 논문집
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• 제12권1호
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• pp.31-35
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• 2022

This study has been carried out in order to improve the rolling problem by enhancing steering stability compared to the 2021 Student Car of the KNUT_EV team for KSAE. Among the various factors affecting steering performances, it was focused on the height of the centroid of weight, the motion ratio, and the spring deflection. In the 2022 Car, a pull rod suspension was used to reduce the height of the centroid of weight and designed with a structure of the rod and rocker to satisfy the target motion ratio. The spring deflection was testified by ADAMS and ABAQUS analysis, and the spring stiffness was selected at 350lb/inch and 450lb/inch for the front and rear wheels, respectively. As a result, the rolling angle of the 2022 Car was reduced compared to the 2021 Car, and the rolling phenomenon was improved.

• Patent21
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• 통권93호
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• pp.30-37
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• 2011

지적재산(IP)은 때때로 이해당사자들 간의 이익에 대항하여 신뢰의 기반을 약하게 만들고 그 과정을 더디게 만들지만, 표준 발전에 있어서는 필수적이다. 더디게 진행되거나 실재하지 않는 표준의 발전은 국제적으로 인정된 표준을 발전시킬 수 있는 잠재적 시장의 손실로 직결된다. 표준 발전 기관들(SDO)은 공정성과 신뢰를 확실히 다짐으로써 새로운 시장을 형성할 수 있다. IEEE 표준 협회 (IEEE-SA)는 표준발전기관으로서, 국제적으로 인정된 특허 정책을 가지고 그 결과를 용이하게 만들 수 있도록 특정한 단계를 정의하고 있다. 이 칼럼은 IEEE-SA의 정책 수립에 지침서가 되는 근본적인 원칙들과, 정책의 다섯 가지 주요 요소들을 설명하고, 표준개발자들과 관계자들이 표준 형성 과정의 성공과 시장발전의 도모를 위한 특정한 기대치에 동의할 수 있도록 하는 IP와 표준의 통합과정을 제시한다.

• 한국프랜차이즈경영연구
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• 제8권1호
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• pp.5-18
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• 2017

Purpose - Although literature has established the relevance of entrepreneurial orientation(EO) in the performance of conventional firms, the constraining nature of franchise arrangement makes one wonders if the same relationship holds for companies operating under the business model. Research design, data, and methodology - Using Nigeria - a country with high potential for franchise growth - as a context, this study aims to explore the relevant entrepreneurial orientation skills exhibited by franchisees and show the extent to which these skills influence their business performance and intention to remain. 26 franchisees purposively selected from six local franchise brands in Nigeria were interviewed. Result and Conclusions - The three classic entrepreneurial orientation factors of innovativeness, proactiveness and risk-taking were found to have varying influence on franchisees' business outcomes. This study answers the calls for more in-depth understanding of the relationship between EO and firm performance generally and, franchise firm performance in particular. The value of this effort lies in the fact that it strengthens theory and updates literature on the subject. Based on the findings, specific recommendations are offered to help improve the practice of franchising in Nigeria.

• Asia Marketing Journal
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• 제16권1호
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• pp.117-132
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• 2014

This study examined the use of Facebook in United Arab Emirates. There were two objectives of this study. The first purpose was to identify the motive for the use of Facebook among people in U.A.E. This study conducted the survey using both qualitative and quantitative methods. One hundred eighty-three working people were used from the survey. Thirty-five questions identified from the interviews were used for the questionnaire design in quantitative method. Factor analysis showed six factors namely usefulness, usage, reliability, making new friends, ethical issue and openness of information. The total variance explained by all the factors was fifty-two percent. This study also examined the demographic variables whether they would play an important role in using the social network site. The study included two more variables, income and married status, which were not frequently examined by previous studies. MANOVA showed statistical significant differences (p < .01) across six factors. ANOVA results showed that gender variable affected only the factor of openness of information. Males were more likely to share their information compared to females. Income variable affected all the factors except the openness of information. The results showed that high-income people had the highest meanscores on three factors (usage, reliability, making new friends) while low-income people had the highest means on usefulness and ethical factors.Marital status had significant effects on usefulness, reliability, and ethical factors. Married people had the low scores on reliability and ethical factors. Lastly, education variable had no effect on all the factors examined.