• Journal of the Ergonomics Society of Korea
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• v.29 no.4
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• pp.435-444
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• 2010

To identify and evaluate the risk factors in WMSD work, a number of ergonomic workload evaluation methods have been developed. In the legal examination of WMSD risk factors, simple observational workload evaluation methods are widely used instead of using costly measurement equipments such as EMG and motion analyzer. The simple workload evaluation methods can be categorized into three groups; risk factor checklist methods, posture observation methods, and manual material handling task evaluation methods. In terms of the categories, this survey summarized several representative workload evaluation methods and compared them each other. Then some industrial application cases referring each the workload evaluation methods were surveyed. Due to the characteristics of each method, the selection and application procedure of workload evaluation method should be appropriate for the corresponding work. Therefore, some guidelines for the selection and application procedure of workload evaluation method were suggested.

• Journal of The Korean Astronomical Society
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• v.34 no.4
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• pp.237-241
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• 2001

Our goal is to present a simple volume-of-fluid type interface-tracking algorithm to compressible two-phase flow in two space dimensions. The algorithm uses a uniform underlying Cartesian grid with some cells cut by the tracked interfaces into two subcells. A volume-moving procedure that consists of two basic steps: (1) the update of volume fractions in each grid cell at the end of the time step, and (2) the reconstruction of interfaces from discrete set of volume fractions, is employed to follow the dynamical behavior of the interface motion. As in the previous work with a surface-tracking procedure for general front tracking (LeVeque & Shyue 1995, 1996), a high resolution finite volume method is then applied on the resulting slightly nonuniform grid to update all the cell values, while the stability of the method is maintained by using a large time step wave propagation approach even in the presence of small cells and the use of a time step with respect to the uniform grid cells. A sample preliminary numerical result for an underwater explosion problem is shown to demonstrate the feasibility of the algorithm for practical problems.

• Journal of the Korean Geotechnical Society
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• v.17 no.4
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• pp.117-126
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• 2001

도로교의 대표적인 기초형식인 말뚝기초에 대한 내진설계방법으로 여러 가지 방법들이 제안되어 있다. 이 중 동적해석법과 같은 복잡한 절차에 의한 해석은 적용성에 한계가 있을 수 있고, 실무에서의 적용상 많은 어려움이 예상되었다. 본 연구에서는 등가정적해석법을 이용한 도로교 기초 말뚝에 대한 간편한 내진설계절차를 제안하였으며, 사례에 적용하였다. 또한, 제안된 간편한 내진설계절차에 사용할 수 있는 해석코드의 적용성을 확인하기 위하여 수식적 정해에 의한 계산결과를 기준 값으로 하여 해석코드에 의한 해석결과들을 비교.분석하였다. 또한, 지진 진동을 이용한 동적 해석결과와 SPS 상호작용(Superstructure - pile - soil interaction)을 고려한 해석결과를 수식적 정해에 의한 결과와 비교.분석하였다.

• Journal of Korean Foot and Ankle Society
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• v.16 no.3
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• pp.162-168
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• 2012

Accessory navicular is a congenital anomaly of the tuberosity of the navicular from a secondary ossification center. The accessory navicular is occasionally the source of pain and local tenderness over the medial side of midfoot. If conservative treatment fails for the painful accessory navicular, surgical treatment is required. There are several surgical option for accessory navicular, which vary from simple excision, percutaneous drilling, modified Kidner procedure and osteosynthesis of the accessory ossicle to the navicular body. In addition, symptomatic flatfoot deformity should be addressed concomitantly.

• Coupled systems mechanics
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• v.4 no.2
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• pp.137-155
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• 2015

This paper presents a simple procedure to obtain a substitute, homogenized mechanical response of single layer graphene sheet. The procedure is based on the judicious combination of molecular mechanics simulation results and homogenization method. Moreover, a series of virtual experiments are performed on the representative graphene lattice. Following these results, the constitutive model development is based on the well-established continuum mechanics framework, that is, the non-linear membrane theory which includes the hyperelastic model in terms of principal stretches. A proof-of-concept and performance is shown on a simple model problem where the hyperelastic strain energy density function is chosen in polynomial form.

• Proceedings of the Korean Reliability Society Conference
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• 2001.06a
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• pp.455-462
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• 2001

We propose a new method to evaluate the network reliability which greatly reduces the intermediate steps toward calculations of maximum capacity flow by excluding unnecessary simple paths contained in the set of failure simple paths. By using signed simple paths and signed flow, we show that our method is more efficient than that of Lee and Park (2001a) in the number of generated composite paths and in the procedure for obtaining minimal success composite paths. Numerical examples are given to illustrate the use and the efficiency of the method.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.9
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• pp.1241-1244
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• 2020

In this paper, we consider a downlink non-orthogonal multiple access system with a base station and N mobile stations, where we assume that instantaneous channel state information (CSI) is available at the base station. A power allocation scheme is proposed to achieve perfect fairness, which means equal data rates for all mobile stations. However, the power allocation scheme using full CSI requires high complexity. Hence, a simple power allocation scheme with low complexity is proposed by using high signal-to-noise power ratio (SNR) approximation. The simple power allocation scheme can achieve perfect fairness only for high SNR. However, it needs only the best CSI and the simple procedure to obtain power allocation coefficients. From simulation results, we show that the simple power allocation scheme provides remarkable fairness performance at high SNR.

• Proceedings of the KIEE Conference
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• 1979.08a
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• pp.21-24
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• 1979

• 한국전자현미경학회:학술대회논문집
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• 1995.06a
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• pp.52-52
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• 1995

• Bulletin of the Korean Chemical Society
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• v.34 no.4
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• pp.1266-1268
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• 2013