• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2004년도 춘계학술대회 논문집
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• pp.311-316
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• 2004

항만을 출입항하는 선박의 통항 안전을 확보하기 위해서는 방파제와 같은 항만 시설물의 설계 또는 배치시에는 우선적으로 선박의 조종 성능을 감안하여 교통 흐름이 원활하도록 적정한 항로를 지정하여야 한다. 이 연구에서는 부산항 및 감천항 입항을 위해 방파제 인접 항로에서 일정 침로로 접근하는 컨테이너 선박이 외력인 바람, 조류, 파랑에 의해 선체에 발생하는 횡압류 및 회두 현상을 정량적으로 분석하여, 선속에 따라 외력을 상쇄하기 위해 취해야 할 대응타각을 산출한다. 또한 향후 방파제 설계 및 배치시 고려해야 될 외력하의 선박의 조종 성능 요소를 제안함과 동시에 방파제의 설계와 항로 배치와의 관계에 대하여 고찰한다.

• 대한치과보철학회지
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• 제31권4호
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• pp.643-659
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• 1993

This study was performed for the purpose of evaluating the stress distributions around five different types of implants according to their structures. The stress distribution around the surrounding bone was analysed by two-dimensional photoelastic method. Five epoxy resin models were made, and vertical and lateral forces were applied to the models. A circular polariscope was used to record the isochromatic fringes. The results of this study were summerized as follows : 1. Threaded type implants showed more even stress distribution patterns than cylinderical type implants when vertical and lateral forces were applied. 2. The stress concentrated patterns were observed at the neck portion and middle portion of the cylindrical type implants comparing with threaded type implants when vertical force was applied. 3. Model 1 and model 4 which are tthreaded type implants showed similar stress distribution patterns at the middle and apical portions and more stress was concentrated at the neck porion of model 1 comparing with model 4 when vertical force was applied. The stresses around model 1 were more evenly distributed when lateral force was applied. 4. More stress was concentrated at the neck and middle portion of cylindrical type implants than threaded type implants when lateral force was applied. 5. Model 1 showed the most even stress distribution patterns when lateral force was applied and stress distribution did no occured at the apical portion of modedl 2 when lateral force was applied. 6. There were almost no differences in stress concentrated patterns with or without having hollow design. And the stress concentrated patterns were observed at the corner of apex in model 5 which has hollow design when vertical force was applied.

• 한국철도학회논문집
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• 제10권6호
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• pp.806-811
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• 2007

탈선은 차륜 플렌지가 레일에 접촉할 때 발생하는 횡방향의 힘이 커져 차륜이 레일을 이탈하는 현상이다. 탈선 또는 주행안전도를 평가하는 대표적인 기준은 탈선계수이다. 차륜에 스트레인게이지를 부착하여 탈선계수를 측정하는 기존방법은 대단히 복잡하고 측정의 실패확률도 높으며, 고도의 측정기술과 고가의 비용이 요구되고 있다. 따라서 안전성확인이 필요한 그 시점에 즉시 확인하지 못하고 있어 안전확보에 어려움을 겪고 있다. 본 논문에서는 차륜과 레일간의 접촉력인 윤중과 횡압을 쉽게 측정할 수 있는 방안을 집중적으로 연구하였으며, 가속도과 변위의 거동만으로 탈선 가능성을 예측할 수 있는 새로운 탈선계수 측정방법을 제시하였다.

• 대한토목학회논문집
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• 제29권6A호
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• pp.587-596
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• 2009

본 연구는 외부 후 긴장력 횡분배 거동을 연구하고 일부 거더 외부 후 긴장만 으로 공용중인 강합성형교 보강 가능성을 평가하기 위한 연구이다. 실험 및 해석적 연구로부터 부분 거더 긴장만으로도 강합성형교 보강이 가능한 것으로 나타났으며, 브레이싱에 의하여 긴장력 횡분배 거동이 개선되는 것으로 평가되었다. 강성비, 거더 간격, 경간장의 영향을 받는 긴장력 횡분배 거동은 교량 형태 및 긴장되는 거더 위치에 의해 변화하는 것으로 분석되었으며, 외부 후 긴장력 횡분배 거동을 예측하는 제안식을 도출하여 합리성을 평가 하였다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2009년도 춘계학술대회 논문집
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• pp.315-319
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• 2009

Investigation of the lateral force fluctuations in an axisymmetric overexpanded compressed truncated perfect (CTP) nozzle for the shutdown transient is presented. These nozzles experience side-loads during start-up and shut-down operations, because of the flow separation at nozzle walls. Two types of flow separations such as free shock separation (FSS) and restricted shock separation (RSS) shock structure occur. A two-dimensional unsteady numerical simulation has been carried out over an axisymmetric CTP nozzle to simulate the lateral force fluctuations in nozzle during shutdown process. Reynolds Averaged Navier-Stokes equations are numerically solved using a fully implicit finite volume scheme. Governing equations are solved by coupled implicit scheme. Two equation k-$\omega$ SST turbulence model is selected. Unsteady pressure is measured at four locations along the nozzle wall. Present pressure variation compared well with the experimental data. During shutdown transient, separation pattern varies from FSS to RSS and finally returns to FSS. Several pressure peaks are observed during the RSS separation pattern. These pressure peaks generate lateral force or side loads in rocket nozzle.

• 한국정밀공학회지
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• 제31권9호
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• pp.759-764
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• 2014

Lateral force of wheel is important parameter when we evaluate the safety of a railway vehicle on curved track. The lateral force of wheel is influenced by the steering performance of wheelsets. Generally, in passive type vehicles, the steering performance of wheelsets is influenced by the parameters like primary spring stiffness, wheel base, conicity of the wheel profile, etc. But, the steering performance of passive type vehicle has its limit. To overcome the limit of the steering performance of passive type vehicle, active steering technology is being developed. In this paper, we analyze the lateral force of wheel and the safety of the railway vehicle on curved track by adopting the active steering technology. As results of dynamic analysis for vehicle model equipped with active steering system, the lateral force of wheel is reduced and the safety is improved remarkably.

• 제어로봇시스템학회논문지
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• 제21권7호
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• pp.595-601
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• 2015

This paper presents an unified chassis control with electronic stability control (ESC) and active front steering (AFS) under lateral force constraint on AFS. When generating the control yaw moment, an optimization problem is formulated in order to determine the tire forces, generated by ESC and AFS. With Karush-Kuhn-Tucker optimality condition, the optimum tire forces can be algebraically calculated. On low friction road, the lateral force in front wheels is easily saturation. When saturated, AFS cannot generate the required control yaw moment. To cope with this problem, new constraint on the lateral tire force is added into the original optimization problem. To check the effectiveness of the propose method, simulation is performed on the vehicle simulation package, CarSim.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.481-484
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• 2008

The important factor to evaluate the running safety of a railway vehicle would be the interaction force between wheel and rail(derailment coefficient), for which is one of important factors to check the running safety of a railway vehicle that may cause a tragic accident. Element that analyze derailment coefficient is consisted of wheel load and lateral force. In this paper, studied about method that calculate vertical force(wheel load) by bending load of axle in rolling stocks.

• Journal of Electrical Engineering and Technology
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• 제11권4호
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• pp.1042-1048
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• 2016

This paper presents a lateral displacement restoring force control for the independently rotating wheelsets (IRWs) of shallow-depth subway systems. In the case of the near surface transit, which has recently been introduced, sharp curved driving performance is required for the city center service. It is possible to decrease the curve radius and to improve the performance of the straight running with the individual torque control. Therefore, the individual torque control performance of the motor is the most important point of the near surface transit. This paper deals with a lateral displacement restoring force control for sharp curved driving. The validity and usefulness of the proposed control algorithm is verified by experimental results using a small-scale bogie system.

• 해양환경안전학회지
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• 제22권5호
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• pp.373-379
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• 2016

접이안이나 사고선박 예인 등 선체를 횡방향으로 이동시 유압력은 수심/흘수비(h/d)에 따라 상당히 달라진다. 하지만 h/d에 따른 유압횡력계수는 선종에 따라 다소 차이가 나는 것으로 알려져 있지만 OCIMF에서 제시하고 있는 유조선 이외의 선종에 대해서는 관련 연구가 많지 않다. 따라서 본 연구에서는 93 m 여객선형 선박에 대한 횡이동 실선실험을 통하여 h/d에 따른 유압력횡력계수를 이론식에 적용하여 상호 비교 평가하였다. 그 결과 대상선박은 h/d=1.6에서는 유압횡력계수를 1.9로 사용할 경우 총저항이 14.0톤으로 실측된 13.8톤의 장력과 거의 유사하였고, h/d=3.0에서는 유압횡력계수를 1.3으로 가정할 경우 19.9톤으로 실측된 장력 20.0톤과 거의 유사하였다. 또한 예인삭의 길이를 30 m에서 60 m로 변경하여 실시한 예인 결과 장력이 거의 유사한 패턴을 보이고 있어 예인삭을 30 m 이상 사용할 경우 배출류에 의한 영향은 거의 없는 것으로 판단된다.