• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.963-969
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• 2010

The railway vehicle consists of wires, bodies, bogies and wheelsets, and each part has very complex mechanism. In this paper, wheel-rail contact algorithm is implemented using C++ and inserted into the ODYN which is a dynamic analysis program. To analyze wheel-rail contact mechanism, information such as contact points, contact angle and rolling radius is calculated according to the wheel and rail profile. Using this information, a table for the calculation of the wheel-rail contact analysis is made according to the lateral displacement. And, the creepage and normal force are calculated and a creep force is estimated by the FASTSIM. To verify the reliability of the wheel-rail contact algorithm, results of the program are compared with the ADAMS/Rail and paper. Finally, a wheelset of the railway vehicle is modeled using ODYN and simulated static and dynamic analysis. And, to verify the reliability of the simulation results, a displacement, velocity, acceleration and force are compared with results of ADAMS/Rail.

• 제어로봇시스템학회논문지
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• 제14권1호
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• pp.62-69
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• 2008

A specialized anthropomorphic robot hand which can be attached to the biped humanoid robot MAHRU-R in KIST, has been developed. This built-in type hand consists of three fingers and a thumb with total four DOF(Degrees of Freedom) where the finger mechanism is well designed for grasping typical objects stably in human's daily activities such as sphere and cylinder shaped objects. The restriction of possible motions and the limitation of grasping objects arising from the reduction of DOF can be overcome by reflecting a typical human finger's motion profile to the design procedure. As a result, the developed hand can imitate not only human hand's shape but also its motion in a compact and efficient manner. Also this novel robot hand can perform various human hand gestures naturally and grasp normal objects with both power and precision grasping capability.

• 융합보안논문지
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• 제6권2호
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• pp.21-29
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• 2006

소프트웨어를 대상으로 하는 다양한 공격방법이 등장하고 있는 가운데 컴퓨터 소프트웨어에 대한 불법 조작 및 변조 등의 위협이 증가하고 있다. 특히, 온라인상에서 동작하는 어플리케이션 클라이언트를 대상으로 악의적인 로더 프로그램을 이용하여 프로그램의 코드를 조작하고, 흐름을 변조하여 정상적인 동작을 방해하는 행위가 날로 늘어나고 있다. 본 논문에서는 악의적인 용도로 사용되는 로더가 가지는 패턴을 분석하여 시그너처를 생성하고, 변형된 패턴을 탐지할 수 있고 시그너처 기법을 보완한 프로파일 기반의 탐지 기법을 제시한다.

• Genomics & Informatics
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• 제5권1호
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• pp.32-35
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• 2007

Telomerase reverse transcriptase (TERT) is an enzymatic ribonucleoprotein that prolongs the replicative life span of cells by maintaining protective structures at the ends of eukaryotic chromosomes. Telomerase activity is highly up-regulated in 85-90% of human cancers, and is predominately regulated by hTERT expression. In contrast, most normal somatic tissues in humans express low or undetectable levels of telomerase activity. This expression profile identifies TERT as a potential anticancer target. By using an RNA mapping strategy based on a trans-splicing ribozyme library, we identified the regions of mouse TERT (mTERT) RNA that were accessible to ribozymes. We found that particularly accessible sites were present downstream of the AUG start codon. This mTERTspecific ribozyme will be useful for validation of the RNA replacement as cancer gene therapy approach in mouse model with syngeneic tumors.

• 대한치과교정학회지
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• 제16권2호
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• pp.107-114
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• 1986

This study was undertaken to determine the adequate bracket position in Korean. The subjects were consisted of casts and photographs of 30 males & 30 famales. They had acceptable profile, normal occlusion, no loss of teeth and no experience of dental treatment. The following conclusions were obtained. 1. In case of no necessity of the posterior teeth movement, bracket angulation was made automatically by paralleling the bracket slot with occlusal plane. 2. Axial inclination of all teeth were measured, and those of canine & premolar were much variable. 3. Adequate bracket position of Korean occlusion were obtained.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2005년도 전기학술대회논문집
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• pp.222-227
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• 2005

A Flapping foil produces an effective angle of attack, resulting in a normal force vector with thrust and lift components, and it can be expected to be a new highly effective propulsion system. A heaving foil model was made and it was operated within a circulating water channel at low Reynolds numbers. The unsteady thrust and lift acting on the heaving foil were measured simultaneously using a 6-axis force sensor based on force and moment detectors. We have been examined various conditions such as heaving frequency and amplitude in NACA 0010 profile. The results showed that thrust coefficient and efficiency increased with reduced frequency and amplitude. We also presented the experimental results on the unsteady fluid forces of a heaving foil at various parameters.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 추계학술대회 논문집
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• pp.460-464
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• 2009

This study investigates the wake effect of an island to develop the offshore wind farm. The main wind direction can be determined from the data processing of the QuikSCAT satellite data around the Wi-do island at south-west sea of the Korean peninsula. Computational fluid dynamics is adopted to analyze the wake effect. From this study the velocity defects due to the wake are revealed. In particular about 5% velocity defect is observed at 80m hub height from the sea surface.

• 소성∙가공
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• 제1권1호
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• pp.95-103
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• 1992

The plane strain analysis for simulating the stretch/draw forming operation with an arbitrarily-shaped tool profile is introduced. An implicit, incremental, updated Lagrangian formulation with a rigid-viscoplastic constitutive equation is employed. Contact and friction are considered through the mesh-normal, which compatibly describes arbitrary tool surfaces and FEM meshes without depending on the explicit spatial derivatives of tool surfaces. The linear line elements are used for depicting the formed sheet, based on membrane approximation. The FEM formulation is tested in the sections of automotive inner panel and two-side draw-in. Not only the excellent agreement between measured and computed strains is obtained in the stretched section, but also the numerical stability of formulation is verified in the draw-in section.

• 한국초전도ㆍ저온공학회논문지
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• 제7권2호
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• pp.1-6
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• 2005

The Particle Image Velocimetry (PIV) technique can be used to obtain a whole-field view of thermal counterflow velocity profile in He II. Using commercially available microspheres, we have been able to visualize the normal fluid velocity in He II thermal counterflow; however, the measured velocities are less than predicted from the two fluid model. None the less, the PIV is a useful tool for observing the counterflow field in He II flow, particularly where the flow is complex as occurs through channel constrictions or around bluff objects. The present paper shows recent results using PIV to observe He II counterflow. Two cases are discussed: 1D channel flow and turbulent flow around a circular cylinder.

• 구강회복응용과학지
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• 제22권1호
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• pp.89-100
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• 2006

Traditionally, goals of orthodontic treatment fall into four categories: good tooth alignment, improvement of skeletal profile and good soft tissue, and rehabilitation of the normal function. Electromyography (EMG) has proven as useful tool in evaluating masticatory function among the maxillomandibular relationship and could be useful in accompanying orthodontic treatment objectives. But in pursuit of clinical application, it is necceassry to systemize clinical guideline for diagnosis by EMG records in evaluating the effects of orthodontic, orthopedic, or surgical treatment. This study present 3 orthodontic cases, which treatment results, ie neuromuscular balances of masticatory muscle, could be moitered by EMG procedure.