• 한국강구조학회 논문집
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• 제12권1호통권44호
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• pp.103-110
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• 2000

현수교는 정착 형식에 따라 타정식과 자정식으로 나누는데, 본 연구는 이 두 가지의 정착 형식의 이동하중에 대한 동적 효과의 차이를 살펴보기 위한 것으로, 연구 결과를 동적확대계수를 차량의 속도와 중량의 효과에 대해 제시함으로써 살펴보았다. 본 연구에 유한요소법을 이용하였다. 비선형 다엽식 현가장치와 트랙터-트레일러의 타이어를 모델링하기 위해 6자유도 시스템으로 차량을 모델링 하였다. 교량은 3차원 프레임 요소와 3차원 탄성현수선 요소로 모델링하였다. 바닥판 상부의 조도를 실제의 도로로부터 얻은 스펙트럼으로부터 노면형상을 생성하여 사용하였다.

• 한국환경교육학회지:환경교육
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• 제9권1호
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• pp.17-29
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• 1996

'Control of Locus of Reinforcement(LOCR)' is considered one of the main important factors on responsible environmental behaviors(REB). It is defined as 'an individual's perception of his or her ability to bring about change through his or her behavior'. This phychological construct is divided in two, external locus and internal locus. Internal locus of reinforcement is important as predictor for REB. Lately, 'The Environmental Action Internal Control Index:EAICI' was developed. It is a valid and reliable instrument to measure relationships of two variables. The purposes of this study were to analyse the orientation of LOCR in high school students and relations with LOCR to REB. By the results, EAICI scores of total students, males, females are 99.83, 95.10, 104.56, respectively. LOCR of females was stronger and more internal than one of males. The item scores for behaviors that reduce the amount of household trash by reusing and recycling and convince someone to do this are 4.31, 4.05, respectively. The item scores for behaviors that convince someone to sign a petition regarding on environmental issues, convince someone to reuse envelopes by putting a label over the old address and convince someone to keep car tires properly inflated are 3.09, 3.09, 3.04, respectively. It shows that EAICI scores are dependent upon the degree of the chances and experiences to meet the various environmental events.

• 제어로봇시스템학회논문지
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• 제17권9호
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• pp.892-896
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• 2011

This paper describes a camera-based position measurement system for automatic tracking control of a rubber Tired Gantry Crane (RTGC). An automatic tracking control of RTGC depends on the ability to measure its displacement and angle from a guide line that the RTGC has to follow. The measurement system proposed in this paper is composed of a camera and a PC that are mounted on the right upper between front and rear tires of the RTGC's side. The measurement accuracy of the system is affected by disturbances such as cracks and stains of the guide line, shadows, and halation from the light fluctuation. To overcome the disturbances, both side edges of the guide line are detected as two straight lines from an input image taken by the camera, and parameters of the straight lines are determined by using Hough transform. The displacement and angle of the RTGC from the guide line can be obtained from these parameters with the robustness against the disturbances. From the experiments with the disturbances, we found the accurate displacement and the angle from the guide line that have the standard deviations of 0.95 pixels and 0.22 degrees, respectively.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2015년도 춘계학술대회
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• pp.346-349
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• 2015

일반적으로 타이어의 마모도나 비정상적인 마모를 알아보기 위해서는 운전자나 정비사가 직접 타이어를 육안으로 타이어의 마모도 및 타이어의 이상 여부를 확인하거나, 측정 게이지 장비를 이용한 방법을 이용한다. 이러한 방법은 개개인의 주관적인 판단이 들어가거나 시간적인 부담과 휠 얼라인먼트 장비를 사용하는 비용을 지불하게 되어 운전자가 받는 부담을 더욱 클 수밖에 없다. 그래서 본 논문에서는 이상마모와 타이어의 마모도를 체크 하고자 복수개의 레이저 센서를 이용하여 각 타이어마다 이상마모와 타이어의 마모도를 체크하고 타이어의 정보를 알기 위해 타이어의 옆면을 체크 하는 시스템을 개발하여 주관적인 판단을 극복하고 객관적이고 정확한 판단을 내릴 것이다.

• 제어로봇시스템학회논문지
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• 제15권7호
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• pp.753-759
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• 2009

As many systems depend on electronics in an intelligent vehicle, concern for fault tolerance is growing rapidly. For example, a car with its braking controlled by electronics and no mechanical linkage from brake pedal to calipers of front tires(brake-by-wire system) should be fault tolerant because a failure can come without any warning and its effect is devastating. In general, fault tolerance is usually designed by placing redundant components that duplicate the functions of the original module. In this way a fault can be isolated, and safe operation is guaranteed by replacing the faulty module with its redundant and normal module within a predefined interval. In order to make in-vehicle network fault tolerant, this paper presents the concept and design methodology of an IEEE 1451 based dual CAN module. In addition, feasibility of the dual CAN network was evaluated by implementing the dual CAN module.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.570-573
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• 2003

Wheels for passenger car support the car weight with tires. and they transmit rolling and braking power into the ground. Whittliing away at wheel weight is more effective to boost fuel economy that lighting vehicle body structure. A shape of hole in disk is optimized for minimizing the weight of steel wheel. Pro/ENGINEER program is used for formulating the design model. and ANSYS package is selected for analyzing the design model. It has difficulties 10 interface these commercial software directly. For combining both programs. response surface methodology is applied to construct approximation functions for maximum stresses and maximum displacements are obtained by full factorial design of five levels. This steel wheel is modeled in 14-inch diameter of rim. and wide parameter of hole in disk is only selected as design variable for reducing the weight of steel wheel. PLBA(Pshenichny·Lim-Belegundu_arora) algorithm. which uses the second-order information in the direction finding problem and uses the active set strategy. is used for solving optimization problems.

• 한국소음진동공학회논문집
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• 제15권10호
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• pp.1202-1210
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• 2005

This paper develops a computer model for estimating the bump characterisitcs of a cat)over type large-sized truck. The truck is composed of front and rear suspension systems, a frame, a cab, and ten tires. The computer model is developed using MSC.ADAMS. A shock absorber, a rubber bush, and a leaf spring affect a lot on the dynamic characteristic of the vehicle. Their stiffness and damping coefficient are measured and used as input data of the computer model. Leaf springs in the front and rear suspension systems are modeled by dividing them three links and joining them with joints. To improve the reliability of the developed computer model, the frame is considered as a flexible body. Thus, the frame is modeled by finite elements using MSC.PATRAN. A mode analysis is performed with the frame model using MSC.NASTRAN in order to link the frame model to the computer model. To verify the reliability of the developed computer model, a double wheel bump test is performed with an actual vehicle. In the double wheel bump, vortical displacement, velocity, acceleration are measured. Those test results are compared with the simulation results.

• Advances in concrete construction
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• 제6권1호
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• pp.87-102
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• 2018

Utilization of waste tires may be considered as one of the solution to the problems faced by the local authorities in disposing them. Reclaimed rubber (RR) is being used in concrete for replacing conventional aggregates. This research work is focused on the strength prediction of reclaimed rubber concrete using a Genetic Algorithm (GA) for M40 grade of concrete and comparing it with experimental results. 1000 sets were taken and 100 iterations were run during training of GA models. A base study has been carried out in this research work partially replacing cement with three types of fillers such as Plaster of Paris (POP), Fly Ash (FA) and Silica Fume (SF). A total of 243 cubes were cast and tested for compression using a Universal Testing Machine. It was found that SF produced maximum strength in concrete and was used in the main study with reclaimed rubber. Tests were conducted on 81 cube samples with a combination of optimum SF percent and various proportions of RR replacing coarse aggregates in concrete mix. Compressive strength tests of concrete at 7, 14 and 28 days reveal that the maximum strength is obtained at 12 percent replacement of cement and 9 percent replacement of coarse aggregates respectively. Moreover the GA results were found to be in line with the experimental results obtained.

• Coupled systems mechanics
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• 제9권5호
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• pp.455-471
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• 2020

This paper presents the results of the study of vertically natural frequency of tractor tires are effected by changing different ground contacts and inflation pressures using the Free Decay Method. The results show that the natural frequencies of the tire are not affected while the vertical acceleration increased strongly due to the increase of inflation pressure when the tire performs free decay vibration on rigid ground. In addition, the number of natural frequency peaks of the tire also increases with increasing tire inflation pressure. On the other hand, the natural frequencies of the tractor tire increases strongly while the vertical acceleration decreases slightly with the increase of tire inflation pressure as the tire performs free decay vibration on soft soil. Further, the natural frequencies of tire-soil system are always higher than that of tire only, and it changed with changing the soil depth. Results also show the natural frequency of tire and tire-soil system is in the range of 3.0 to 10.0 Hz that lie within the most critical natural frequency range of the human body. These findings have to be mentioned and used as design parameters of the tractor suspension system.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.1416-1422
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• 2010

모노레일은 그동안 과좌식과 현수식으로 분류 되어 왔으나 세계 최초로 도입한 중앙 안내 방식의 인천 월미은하레일은 신개념의 Y Beam을 가이드 레일로 사용한 새로운 형식의 모노레일이라 할 수 있다. Y Beam은 안내륜을 통해 모노레일의 수평 하중을 전달하는 역할을 담당하고 있기 때문에 수직 하중을 타이어를 통해 전달 받는 콘크리트 바닥 및 강재 Beam과 함께 모노레일의 주행 안전에 없어서는 안 될 가장 중요한 구조물이다. 본 연구에서는 수평 하중을 감당하고 있을 뿐만 아니라 모노레일의 안정과 안내를 함께 보장 하면서 급전선을 지지하는 역할도 동시에 담당하고 있는 Y Beam과 Y Beam을 고정하는 클램프의 특성과 안전성에 대해 고찰하였다.