• 한국정보통신학회논문지
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• 제6권1호
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• pp.124-132
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• 2002

영상처리라는 것은 문자를 인식하거나 물체를 인식하는 등 어떠한 물체의 특징을 추출하여 그에 대한 정보를 가지고 자동제어 시스템이나 인식시스템에 도입하는 것이다. 그러나 이러한 시스템들에 도입시키기 위해서는 찾고자 하는 물체의 특징을 잘 검출할 수 있어야 하며 검출된 특징의 패턴도 잘 잘 구별해야 한다. 그러나 본 논문에서 다루고 있는 고무 타이어의 특성은 배경과 문자열이 존재하는 특징면이 잘 구분되지 않는다는 것이다. 이것은 곧 특징 추출이 어렵다는 것을 간접적으로 나타내고 있는 것이다. 그러므로 수많은 논문에서 손실된 특징 정보를 복원하기 위한 기술과 끊어진 문자 정보를 유추하여 맞춰 내는 등의 기술을 많이 연구해 왔다. 그러나 우리는 무엇보다 처음에 입력받는 영상이 좋아야만 나머지 필터링이나 영상 처리기법이 쉽다고 생각하여 입력 영상을 개선시킬 수 있는 광학적인 환경에 관심을 두기로 하였다. 본 논문은 이리한 영상처리기법 중에서 입력 영상을 보다 선명하게 받아들이기 위한 조건을 찾고 광학적인 이론을 찾고자 하는 논문이다. 본 논문은 타이어를 생산하는 라인에서 타이어에 각인되어 있는 문자를 인식하고 상위 컴퓨터인 호스트 컴퓨터에 자료를 전송함으로써 물류를 관리하고, 다음 공정인 전수 검사공정에서 각 타이어에 맞는 휠을 끼우기 위한 작업을 위한 것이다. 이러한 시스템을 위해서는 나은 양질의 입력영상을 획득해야만 인식과정에서 오인식을 줄일 수 있고 자동화 공정에 응용할 수 있다. 양질의 입력영상을 획득하기 위해서는 빛의 입사각도와 피사체가 이루는 각도가 어떠한 각의 형태를 가지는가 하는 것이 중요하며 또한 이것을 받아들이는 카메라의 각도가 피사체와 어떠한 각을 이루는가? 하는 것도 중요한 문제이다. 본 논문에서는 이에 대한 최적조건을 실험적인 방법으로 찾고, 이에 대한 결과를 광학적으로 증명해 보고자 한다.

• 대한음성학회:학술대회논문집
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• 대한음성학회 2004년도 춘계 학술대회 발표논문집
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• pp.231-234
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• 2004

This paper describes an efficient method for improving the noise-robustness in speech recognition in a running car by considering wind noise. In driving car, mainly three kind of noises engine noise, tire noise and wind noise, are severely affect recognition performance. Especially wind noise is an important factor in driving car with window opened. We analyzed wind noise in various driving conditions that are 60, 80, 100 km/h with window fully opened, window half opened. We clarified that the recognition rate is significantly degenerated when the wind noise components in the frequency range above 200 Hz are large. We developed a preprocessing method to improve the noise robustness despite of wind noise. We adaptively changed the cutoff frequency of the front-end high-pass filter from 100 through 200 Hz according to the level of the wind noise components. By this method, the recognition rate is considerably improved for all kind of driving conditions

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 춘계학술대회 논문집
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• pp.233-237
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• 2002

Vehicle Dynamics Control(VDC) has been a breakthrough and become a new terminology for the safety of a driver and improvement of vehicle handling. This paper examines the usefulness of a brake steer system (BSS), which uses differential brake forces for steering intervention in the context of VDC. In order to help the car to turn, a yaw moment can be achieved by altering the left/light and front/rear brake distribution. The steering function achieved through BSS can then be used to control lateral position in an unintended road departure system. A 8-DOF non-linear vehicle model including STI tire model will be validated using the equations of motion of the vehicle, and the non-linear vehicle dynamics. Since Fuzzy logic can consider the nonlinear effect of vehicle modeling, Fuzzy controller is designed to explore BSS feasibility, by modifying the brake distribution through the control of the yaw rate of the vehicle. The control strategies developed will be tested by simulation of a variety of situation; the possibility of VDC using BSS is verified in this paper.

• 한국정밀공학회지
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• 제20권5호
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• pp.82-91
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• 2003

Vehicle dynamics control (VDC) has been a breakthrough and become a new terminology for the safety of a driver and improvement of vehicle handling. This paper examines the usefulness of a brake steer system (BSS), which uses differential brake forces for steering intervention in the context of VDC, In order to help the car to turn, a yaw moment can be achieved by altering the left/right and front/rear brake distribution. The steering function achieved through BSS can then be used to control lateral position in an unintended road departure system. An 8-DOF non-linear vehicle model including STI tire model will be validated using the equations of motion of the vehicle, and the non-linear vehicle dynamics. Since fuzzy logic can consider the nonlinear effect of vehicle modeling, fuzzy controller is designed to explore BSS feasibility, by modifying the brake distribution through the control of the yaw rate of the vehicle. The control strategies developed will be tested by simulation of a variety of situation; the possibility of VDC using BSS is verified in this paper.

• Journal of Mechanical Science and Technology
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• 제19권3호
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• pp.792-801
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• 2005

This paper discusses a dc motor equipped electric power steering (EPS) system and demonstrates its advantages over a typical hydraulic power steering (HPS) system. The tire-road interaction torque at the steering tires is calculated using the 2 d.o.f. bicycle model, in other words by using a single-track model, which was verified with the J-turn test of a real vehicle. Because the detail parameters of a steering system are not easily acquired, a simple system is modeled here. In previous EPS systems, the assisting torque for the measured driving torque is developed as a boost curve similar to that of the HPS system. To improve steering stiffness and return-ability of the steering system, a third-order polynomial as a torque map is introduced and modified within the preferred driving torques researched by Bertollini. Using the torque map modification sufficiently improves the EPS system.

• 한국정밀공학회지
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• 제23권5호
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• pp.162-169
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• 2006

Steel cord which is used as reinforcement in car tires is produced by wet-drawing process. Recently the quality improvement of the steel cord product is demanded by the tire market. After cold drawing process, produced residual stresses have a harmful effect on the durability of the wire and become the cause which decreases the quality of the product. Therefore, to improve the quality of the steel cord product, the research regarding the method of residual stress relaxation is necessary. To evaluate the quality of the cold drawn wire, it is very important to measure the residual stress, because the residual stress decides a variety of the quality level which is demanded in the cold drawn wire. The aim of this study is to propose residual stress relaxation method in the drawn wire using FE-analysis. The validity of the analysis results was verified by Nano indentation test.

• 한국자동차공학회논문집
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• 제21권1호
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• pp.121-127
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• 2013

In this study, suspension geometry is controlled to improve vehicle handling performance. The toe and camber of the rear suspension is controlled independently by using a double knuckle structure designed to enhance the vehicle cornering stability. Camber and toe changes in the rear wheel during high speed turning maneuver are important factors that influence the vehicle stability. Toe in the rear outer wheel plays a dominant role in cornering. A control algorithm for the camber and the toe angle input is developed to carry out the control simulation of the vehicle such as single lane change, the steady state cornering, the double lane change and the step steering simulation. Effects of the camber and toe angle control are analyzed from the computer simulations. A double lane change simulation revealed that the suspension mechanism with variable camber angle and variable toe angle decreases the peak body slip angle and peak yaw rate, 50% and 10%, respectively.

• 한국과학교육학회지
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• 제11권1호
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• pp.97-115
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• 1991

The purpose of this study is in making a important way for in-service training of science teacthers. So the study was carried out to analyze the text books of in-service training school in Gyeongnam, Kyungpook, Junpook province and Pusan city and to survey teacher's opinion by questonnaires collected from teachers in Gyeongnam province. The result abtained are as follows : 1. The contents of. tire text books for in-service training course have very critical defference at each province. 2. Most of teachers wanted to get more updating information of the science and more comprehensive knowledge of higher level' of science subject. 3. In order to obtain comprehensive basic concept, develop of inquiry ability, and promote of scientific attitude, the thinking experiment which is selected to experimental subjects of secondary school are need to be selected. 4. The new text-book model for in-service training course should be developed, and the finnancial support will be required to develop such a text.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2002년도 추계학술대회 논문집
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• pp.366-372
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• 2002

Recently the steel parts used at automobiles are required to be used under high stress more than ever before in need of the weight down. To achieve this requirement of a high strength steel, it must be necessary to decrease inclusion content and surface deject as like decarburization, surface roughness etc.. In this study, the surface conditions are measured to know tile influence on fatigue properties by two cases of shot peening of two-stage shot peening and single-stage shot peening. And for this study, three kinds of spring steel (JISG4081-SUP7,SAE 9254, DIN 50CrV4, ) are made. This study shows the outstanding improvement of fatigue properties at tire case of two-stage shot peening in the rotary bending fatigue test and this is assumed to be from (1) Decreasing the surface roughness (2) Unchanging the surface hardness (3) Increasing the compressive residual stress But, results also show fatigue failures originated at inclusion near surface, and this inclusion type is turned out to be a alumina of high hardness.

• Elastomers and Composites
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• 제37권4호
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• pp.234-243
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• 2002

A general scheme of a rubber structure is proposed. Using the thermomechanical method(TMA), some changes in the molecular and topological structures for uncured and cured, and unfilled and filled rubbers during processing are shown. In our investigations as region it is understood a complex structure, which is expressed at the thermomechanical curve(TMC) as a zone differed from others in thermal expansion properties. This zone is between the noticed temperatures of relaxation transitions, usually on the level like those determined by DMTA at 1Hz. These regions, which shares, are not stable, and differ in molecular-weight distribution(MWD) of chain fragments between the junctions. Differences in dynamics of the formation of the molecular and topological structures of a vulcanizate are dependent on the rubber formulation, mixing technology and curing time. Some of characteristics of these regions correlate with mechanical properties of vulcanizates what is shown for NR rubbers containing ENR or CPE as a polymeric additive. It is well known that the state of order influences diffusivity of low-molecular substances into the polymer matrix. Because of this, the two topological amorphous regions should influence the distribution of the ingredients and resulting in rubber compounds' heterogeneity, and related properties of cured rubber. Investigation of this problem is expected to be, in the future, one of the essential factors in determining further improvement of polymeric materials properties by compounding with additives and in reprocessing of rubber scrap.