• Journal of the Korean Arthroscopy Society
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• v.9 no.1
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• pp.60-64
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• 2005

Purpose: To describe the impingement of the osteophyte between the olecranon process and olecranon fossa and to understand the effect of removing the lesion on the elbow extension in heavy workers. Materials and Methods: Arthroscopy was performed to elbow of heavy industrial workers who complained painful limitation of elbow extension.6 patients(Teases) with average age of 43 year were selected. The average ROM showed flexion contracture of $17^{\circ}$ and further flexion of $87^{\circ}$. Results: In all cases, after the operation two months follow up, mean flexion contracture improved from $17^{\circ}\;to\;2^{\circ}$ with further flexion from$87^{\circ}\;to\;122^{\circ}$. After the operation 1 year follow up, the mean flexion contracture was $3^{\circ}$ and further flexion was $113^{\circ}$. Pain relief within acquired range of motion was achieved in all cases and there was no complication in this series. Conclusion: Selective removal of the impingement bony spur for treatment of flexion contracture in the patient with chronic cumulative trauma disorder patients appear to be effective method to control pain, recover joint movement and at] ow early rehabilitation.

• Transactions of the Korean Society of Automotive Engineers
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• v.18 no.5
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• pp.20-24
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• 2010

The position of the automobile's head restraint is very important for the neck injury in rear end collision. This study is about influence of the head restraint height and distance on neck injury during rear end collision. The effects of the position have been evaluated experimentally. The neck injuries are calculated by the relative acceleration between the upper and lower neck. As a result, It is found that the head restraint should be close enough to the back of the head and high enough to the top of the head.

• Journal of the Korean Magnetics Society
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• v.6 no.2
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• pp.122-129
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• 1996

Fig. 1에서 보는 바와 같이 수 MeV의 에너지를 가진 입사이온이 고체 시료표면과 충돌했을 때 여러 가지의 상호작용과 과정들이 일어난다. 입사 아온이 표적원자의 원자가전자나 내각전자와 상호작용을 하였을 때 원자를 여기시키거나 이온화시키게 되며 입사 이온이 표적 핵과 매우 가까이 접근했을 때 입사이온과 표적 핵사이에 쿨롱상호작용이나 핵 상호작용이 일어나게 된다. 이러한 여러가지 상호작용의 결과들로부터 분석하고자 하는 시료의 성분, 구조, 상호작용 과정에 대한 정보를 얻을 수 있다. 이러한 고에너지 이온선을 이용한 분석기술로는 Fig. 1에서 보는 바와 같이 후방산란법(BS : Backscattering Spectrometry), 전방산란법(FRS : Forward Recoil Spectrometry), 핵반응법(NRA : Nuclear Reaction Analysis), 양성자여기X선검출법(PIXE : Proton Induced X-ray Emission)등과 이러한 방법들과 같이 조합하여 사용하는 이온 채널링(ion channeling)등이 있다. 본 해설에서는 이러한 분석법중에서도 널리 사용되고 있는 후방산란법과 이온 채널링에 대하여 주로 기술하고자 한다.

• Korean Journal of Crystallography
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• v.20 no.1
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• pp.1-8
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• 2009

이온산란 분광법(ISS: Ion Scattering Spectroscopy)은 표면 원자의 구조를 러더포드 후방산란법(RBS: Rutherford Backscattering Spectroscopy) 등과 같이 실공간에 대하여 직접 정보를 얻는 방법이다. 그 중에서도 산란각도를 $180^{\circ}$로 고정하여 산란이온 검출기를 설치한 직충돌 이온산란 분광법(ICISS: Impact Collision Ion Scattering Spectroscopy)은 산란된 이온의 궤적이 입사궤도와 거의 동일하기 때문에 산란궤적의 계산이 간단해지고, 최외층 뿐만 아니라 표면에서 수 층 깊이의 원자구조의 해석이 가능하다. 또한 비행시간형(TOF: Time-Of-Flight) 분석기를 채택하여 산란 이온 및 중성원자를 동시에 측정하면 입사 이온의 표면에서의 중성화에 관계 없이 산란 신호를 얻으므로 표면 원자의 결합 특성에 영향 받지 않고 사용할 수 있다. 본고에서는 ICISS의 원리, 장치, 측정방법 등을 소개한 제1편 및 반도체 표면구조, 금속/반도체 계면 등의 해석에 관하여 기술한 제2편에 이어서 세라믹 재료의 표면 원자 구조, 세라믹 박막의 원자 구조, 흡착 기체의 구조, 원소의 편석 등에 관한 연구 사례를 소개하고자 한다.

• Journal of Hydrogen and New Energy
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• v.19 no.4
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• pp.266-275
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• 2008

The performance improvement of each part for durability, safety and cost of high pressure storage system for fuel cell vehicle has been focused so far. However, for the mass production of fuel cell vehicle, it is necessary to evaluate durability and safety in system module and vehicle level. The test procedure to evaluate vibration and collision safety of high pressure hydrogen storage system for the fuel cell vehicle is established and its reliability is verified.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 2009.05a
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• pp.190-195
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• 2009

자동차 이용자 수가 증가 할수록 자동차 사고로 인한 피해도 많이 늘어나고 있다. 이러한 자동차 사고를 사전에 예방하기 위해서는 운전자의 상태 및 현재 차량 상태를 파악하여 사고를 미리 방지함으로서 운전자의 안전을 보조할 수 있는 시스템이 필요하다. 본 연구에서는 안전운전을 보조하기 위하여 졸음운전 여부 감지 시스템, 후진시 후방 안전거리를 감지하는 시스템, 쾌적한 운전 환경을 위한 실내 환경 측정 시스템, 주차 시 생길 수 있는 사고에 대한 감시시스템을 센서와 MCU등을 이용한 임베디드 시스템을 구현 하였다.

• Journal of the Korean Arthroscopy Society
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• v.7 no.1
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• pp.7-9
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• 2003

전방십자인대 재건술시 이식건의 과간 절흔에 대한 충돌을 예방하기 위하여 어느 절도의 절흔 성형을 시행 할 것인가에 대하여는 아직까지 논란이 있으며 수술시 절흔의 형태, 골극 형성 유무, 이식건의 크기 경골 터널의 위치를 고려하여 시행하여야 한다. 절흔 후방의 골 제거가 과도하게 시행 될 경우에는 대퇴골 부착부가 외측으로 전위되어 슬관절의 생역학적 변화를 가져올 수 있고, 주변 관절 연골의 조기 퇴행성 변화를 초래할 수 있으므로 세심한 주의를 기울여야 하며 절흔 성형은 가능한 한 최소화 하는 것이 출혈, 동통 및 부종 등의 술후 합병증을 줄일 수 있다.

• Journal of the Korea Society of Computer and Information
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• v.15 no.7
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• pp.41-47
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• 2010

The emergency between vehicles on the superhighway should be transmitted quickly to the following vehicles for safety of people. The message between them has been transmitted by broadcast method in an wireless environment of 802.11, so far. That causes the broadcast storm and a waste of the bandwidth of Wireless network owing to unnecessary process of sending messages to even vehicles that do not have to receive the information. The message collision is a main cause of the increase of message delay. In order to overcome the existing problem, this paper proposed a message broadcast scheme based on cell (MBC), which is the way to divide cars into different groups by cell unit and transmit messages to the members of the groups through the cell primary (cp) vehicles. This paper shows the proposed broadcast's performance in the same environment is much superior to other conventional broadcast schems for inter-vehicle communication, since the receiving ratio among the following vehicles is improved.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.843-850
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• 2020

The purpose of this study is to evaluate the structural risk and weakness of a railway tank car through nonlinear collision analysis according to overseas collision safety standards. The goal is to propose a crash safety design guideline for railway tank cars for transporting dangerous goods in Korea. We analyzed the buffer impact test procedure of railway freight cars prescribed in EN 12663-2 and the tank puncture test criteria prescribed in 49CFR179. A nonlinear finite element model according to each standard was modeled using LS-DYNA, a commercial finite element analysis solver. As a result of the buffing impact test simulation, it was predicted that plastic deformation would not occur at a collision speed of 6 km/h or less. However, plastic deformation was detected at the rear of the center sill and at the tank center supporting the structure at a collision speed of 8 km/h or more. As a result of a head-on test simulation of tank puncture, the outer tank shell was destroyed at the corner of the tank head when 4% of the kinetic energy of the impacter was absorbed. The tank shell was destroyed in the area of contact with the impacter in the test mode analysis of tank shell puncture when the kinetic energy of the moving vehicle was reduced by 30%. Therefore, the simulation results of the puncture test show that fracture at the tank shell and leakage of the internal material is expected. Consequently, protection and structural design reinforcement are required on railway tank cars in Korea.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.15 no.3
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• pp.201-209
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• 2015

The deformed degree of car body varies largely with the collision part from side collision of car-to-car. In case of deformation of car body caused by collision, the movement is different as speed energy changes to strain energy. Generally, in the analysis of traffic accident, the movement of car after the collision is analyzed by law of conservation of motion and the error of energy absorption rate along the deformation of car body can be calibrated by inputting coefficient of restitution, but it is current situation that coefficient of restitution applied by referring to the research results of forward collision and backward collision because the research results of side collision is rare. Vehicle model of finite element method applied by structure of car body and materials of each component was analyzed by explicit finite element method, and coefficient of restitution and collision detection time along contact part of side collision was drawn by analyzing the results. Analysis result acquired through the law of conservation momentum by applying finally-computed coefficient of restitution and crash detection time compared to collision result of actual vehicle. As a result, the reliability of analysis was higher than the existing analysis method were acquired when applying the drawn initial input value that used finite element method analysis model.