• 한국공작기계학회논문집
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• 제11권2호
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• pp.80-86
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• 2002

Previous method of computer simulation to predict the dynamic response of a vehicle has been based on the assumption that vehicle structure is rigid. If the flexibility of the vehicle structure becomes too large to ignore, rigid body assumption will no longer give good estimation of the dynamic characteristics. Therefore, in order to predict more precise vehicle dynamic characteristics, flexible multi-body dynamic analysis of a vehicle is necessary. This paper investigates dynamic characteristics of vehicle systems with flexible frames numerically. Joint reaction forces, vertical accelerations, pitch accelerations are analyzed for the vehicle systems with various flexible frames using multi-body dynamic analysis code and finite element analysis code.

• 대한기계학회논문집
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• 제12권3호
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• pp.450-456
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• 1988

본 연구에서는 자동차의 동력학적 해석을 위한 특별프로그램을 만들어서 범용 프로그램인 DADS와 효율성을 비교해 보고자 한다.

• Journal of Mechanical Science and Technology
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• 제15권6호
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• pp.693-698
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• 2001

The analysis of actuating forces (or torques) and joint reaction forces (or moments) are essential to determine the capacity of actuators, to control the system and to design the components. This paper presents an inverse dynamic analysis algorithm for flexible multibody systems with closed-loops in the relative joint coordinate space. The joint reaction forces are analyzed in Cartesian coordinate space using the inverse velocity transformation technique. The joint coordinates and the deformation modal coordinates are used as the generalized coordinates of a flexible multibody system. The algorithm is verified through the analysis of a slider-crank mechanism.

• 한국정밀공학회지
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• 제16권11호
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• pp.204-212
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• 1999

In this paper, the vibrational motion of a flexible beam clamped on a translating base and carrying a moving mass is investigated. The equations of motion which describe the total dynamics of the beam-mass-cart system are derived and the coupled dynamic equations are solved by unconstrained modal analysis. In modal analysis, the exact normal mode solutions corresponding to the eigenfrequencies for the position of the moving mass and the ratios of the mass of the flexible beam, the moving mass and the base cart are used. Proper transformations of the time solutions between the normal modes for a position and those for the next position of the moving mass are also adopted. Numerical simulations are carried out to obtain the open-loop responses of the system in tracking the pre-designed path of the moving mass.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 봄 학술발표회 논문집
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• pp.287-294
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• 2002

Underground flexible pipes for electric cables are subject to external loads and surrounding soil pressure. Particularly, strain of flexible pipes is of great concern in terms of safety and maintenance for electric cables. In this study, the actual size tests were carried out to investigate strain-deformation relation for underground flexible pipes subject to vehicle loads with various depths and degree of compaction.

• 한국도로학회논문집
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• 제10권4호
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• pp.213-224
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• 2008

트럭 축하중에 의한 도로포장체의 응력과 변형은 대부분 다층 탄성 이론에 의해 예측된다. 대부분의 다층 탄성 이론에 의한 이론적 계산값이 연성 포장 재료의 점탄성적 거동특성, 동적 트럭 축하중, 비균등 타이어 접지압 및 형상등을 해석에 고려하지 못하므로, 계측값에 비해 매우 작은 값을 예측하므로서 도로 포장 두께설계가 과소 설계될 우려가 크다. 이와 같은 도로 포장체 구조해석시 이용되는 중요한 변동요소를 포장 재료의 물성 모델 측면, 비균등 접지압 및 형상 측면, 동적 유한요소해석 측면에서 분석하여 이용 가능한 모델을 본 논문에서 제안하였다. 경계조건 및 민감도 분석을 수행을 통한 효과적인 3차원 연성포장의 유한요소해석모델을 결정하는 방법론을 제안하였으며, 최적 유한요소모델 분석결과와 현장에서 취득한 결과와의 상호비교를 통하여 모델의 유의성을 검증하였으며, 동적 접지하중조건, 점탄성물성 모델 등을 3차원 유한요소 모델에 접목하고, 최적 경계조건을 결정하였다.

• 패션비즈니스
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• 제25권4호
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• pp.125-140
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• 2021

Recently, flexible displays have been used as part of fashion beyond the concept of parts for electronic products. The flexible display applied to wearable fashion products flexibly bends according to the wearing position of the human body and, at the same time, decorates the fashion product more splendidly through the screen on which images or videos are displayed. Flexible displays, which are used for clothes and accessories, combine analogue fashion sensibility with digital screens to create a new level of convergence product design and expand the range of fashion design and fashion materials. This study aims to analyze the trends of the development and commercialization of fashion products that use flexible displays. As a research method, theoretical research and empirical research through case analysis were conducted in parallel. First, as a theoretical study, the morphological and technical characteristics of flexible displays were examined. Through theoretical studies, the effect of the characteristics of flexible displays on the development of wearable fashion products was investigated. Second, as an empirical case study, the design of wearable fashion products using flexible displays over the past 10 years and the characteristics of the displays used in the products were analyzed. Based on the characteristics analyzed, the product design, display and product integration methods and the commercialization stages of wearable fashion products using flexible displays were analyzed.

• 아태비즈니스연구
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• 제13권1호
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• pp.53-74
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• 2022

Purpose - This study aims to examine the relationship between flexible Human Resource Management (HRM) and individual ambidexterity and the moderating effect of trust in management. Design/methodology/approach - This study collected 971 survey data from employees in Korea. The Confimatory Factor Analysis (CFA) and the multiple regression analysis were used to analyze the data. Findings - First, the flexible human resource management have a positive effect on individual ambidexterity. Second, trust in management positively moderate the relationship between flexible human resource management and individual ambidexterity. Research implications or Originality - First, this study is critical that it examines individual ambidexterity and antecedent factor, which have not been relatively researched in Korea. This study is meaningful in that it revealed that the individual ambidexterity can be increased through flexible human resource management. Second, individual ambidexterity may vary depending on the characteristics of the human resource management system. Third, it is important to find the boundary condition of trust in management. By finding conditions that enhance the effect of flexible human resource management on individual ambidexterity, it also provides practical implications applicable to companies.

• Journal of Advanced Marine Engineering and Technology
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• 제31권6호
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• pp.768-776
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• 2007

In this study, axial vibration analysis has been conducted on a propulsion and lift shafting system for an air cushion vehicle using ANSYS code. The shafting system is totally flexible multi-elements system including wood composite material of air propeller. aluminum alloy of lift fan and thin walled shaft with flexible coupling. The analysis calculated the axial natural frequencies and mode shapes of the shafting system taking into account an equivalent mass-elastic model for shafting system as well as the three-dimensional models for propeller blade and fan impeller. Such a flexible shafting system has very intricate vibrating characteristics and especially, axial natural frequencies of flexible components such as propeller blade and impeller of lift fan can be lower to the extent that causes a resonance in the range of operating revolution. The results for axial vibration analysis are presented and compared with the results of axial vibration test for lift fan conducted during Sea Trial.

• Korean Chemical Engineering Research
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• 제57권3호
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• pp.351-357
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• 2019

2018년 울산에서 Flexible hose의 파단으로 발생한 염소 누출사고를 분석하여 국내 설계 및 관리 기준을 제시하기 위한 연구를 수행하였다. 누출 사고가 발생한데는 다양한 원인이 있지만, 본 논문에서는 직접적 원인인 Flexible hose의 파단을 분석하는데 초점을 맞추었다. 분석 결과, 사고가 발생한 사업장에서 염소 이송에 사용하는 Flexible hose 는 재질 및 사용 두께 측면에서 부적절 했고, 사용 전 압력 테스트도 운전압력 이하에서 하는 등 문제가 있었다. 설문조사를 통하여 염소를 취급하는 울산지역의 다섯 곳의 사업장을 확인한 결과, 한 곳을 제외하고 염소 이송에 부적절한 Flexible hose를 사용하고 있었다. 현재 염소 이송용 Flexible hose의 설계에 대한 국내 기준이 없어 사용하는 Flexible hose의 적정성을 검토하는데 어려움이 있다. 본 연구를 통하여 국내에 적용할 수 있는 염소 이송용 Flexible hose의 설계 기준을 제시하였다. 본 논문에서 제시한 기준을 설계 및 검토에 적용한다면 염소 이송 시 발생할 수 있는 Flexible hose 파단의 위험성을 경감시키는데 기여할 것이다.