• Journal of Institute of Control, Robotics and Systems
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• v.8 no.10
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• pp.898-906
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• 2002

Antilock Brake System (ABS) is designed to prevent wheels from being locked-up under emergency braking of a vehicle. Therefore it improves directional stability of the vehicle, shortens stopping distance, and enhances maneuvering during braking, regardless of road conditions. Hardware In-the-Loop Simulation (HILS) is an effective tool for design Performance evaluation and test of vehicle subsystems such as ABS, active suspension, and steering systems. This paper describes a HILS model for ABS/ ASR(Acceleration Slip Regulation) system applications. A fourteen degrees-of-freedom vehicle dynamics model is simulated in an alpha-chip processor board. The proposed HILS system is tested with a basic ABS control algorithm. The design and implementation of HILS system for the ABS ECU(Electronic Control Unit) development of commercial vehicle are presented. The results show that the proposed HILS system can be used to test the performance, stability, and reliability of a vehicle under braking.

• Journal of Institute of Control, Robotics and Systems
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• v.13 no.8
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• pp.783-789
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• 2007

In this paper, firstly, we propose a generating method of the 3-D obstacle map using ultrasonic sensors. Secondly, we try to find the necessary stimulation conditions of compact tactile display device for effective transfer of obstacle information. The final goal of this research is the development of a walking guide system for the blind to walk safely. The walking guide system consists of a guide vehicle for the obstacle detection and a tactile display device for the transfer of the obstacle information. The guide vehicle, located in front of the walking blind, detects the obstacle using ultrasonic sensors. The processed information makes an obstacle map and transmits safe path and emergency situation to the blind by the tactile display. The tactile display device, located in the handle which is connected with the guide vehicle by cane, offers the processed obstacle information such as position, size, moving, shape of obstacle and safe path, etc. The concept of a walking guide system with tactile display is introduced, and experiments of 3-D obstacle detection and tactile perception are carried out and analyzed.

• Journal of Electrical Engineering and Technology
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• v.3 no.4
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• pp.528-537
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• 2008

Primary frequency control(PFC) has the ability to regulate short period random variations of frequency during normal operation conditions and also to respond rapidly to emergencies. However, during the past decade, numerous significant sized blackouts occurred worldwide that resulted in serious economic losses. Therefore, the conclusion has been reached that the ability of the current PFC to meet an emergency is poor, and security of power systems should be improved. An alternative to enhance the PFC and thus security is to store excessive amounts of energy during off-peak load periods in efficient energy storage systems for substituting the primary control reserve. In this sense, superconducting magnetic energy storage(SMES) in combination with a static synchronous compensator(STATCOM) is capable of supplying power systems with both active and reactive powers simultaneously and very rapidly, and thus is able to enhance the security dramatically. In this paper, a new concept of PFC based on incorporating a STATCOM-SMES is presented. A complete detailed model is proposed and a new control scheme is designed, comprising an enhanced frequency control scheme, and a fully decoupled current control strategy in d-q coordinates with a novel controller to prevent dc bus capacitors voltage drift/imbalance. The performance of the proposed control schemes is validated through digital simulation carried out using MATLAB/Simulink.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.67 no.2
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• pp.57-62
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• 2018

A brush-less type synchronous generator driven by an internal-combustion engine is used for emergency electric source. These types of generators have to maintain a certain range of output voltage even under the sudden load change conditions such as full load application and removal. This paper describes a method for suppressing the output voltage of a synchronous generator that operates excessively when the load fluctuates. The method used in this paper is a feedforward control method in which the main voltage control consists of a feedback loop using a typical PID controller and the load current is detected as a disturbance element and compensated directly. A feedforward system is constructed in which the load current is regarded as disturbance, and the appropriate feedforward controller configuration and parameters are found through simulation. Finally, it can be seen through the experiment that the feedforward control is performed properly. It can be seen that the generator terminal voltage is recovered to the steady state in a short period of time as compared with the existing PID control method even when the entire load of the generator is changed.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.8 s.227
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• pp.1125-1134
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• 2004

This paper presents a mathematical model which is about the dynamics of not only a two wheel steering vehicle but a four wheel steering vehicle. A sliding mode ABS control strategy and PID rear wheel control logic are developed to improve the brake and cornering performances, and enhance the stability during emergency maneuvers. The performances of the controllers are evaluated under the various driving road conditions and driving situations. The numerical study shows that the proposed full car model is sufficient to accurately predict the vehicle response. The proposed ABS controller reduces the stopping distance and increases the vehicle stability. The results also prove that the ABS controller can be employed to a four wheel steering vehicle and improves its performance. The four wheel steering vehicle with PID rear wheel controller shows increase of stability when a vehicle speed is high and sharp cornering maneuver when a vehicle speed is low compared to that of a two wheel steer vehicle.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.3
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• pp.294-300
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• 1995

In aquaculture industrial field, an automatic management and control system is needed to cope with the difficulties such as expensive wage, ripe age of management worker and risk according to the unexpected change of environmental conditions in the aquarium. This paper introduces an automatic aquarium monitoring and control system. The system is developed using PC single board computer. A PC can be connected to multi-single hoard computers, and the communication between PC and single board computers is based on RS-422/485 interfacing method. The physical data of pH, DO, temperature and water level etc. are real-timely treated in the single board computer though individual transducers, transfered to the main monitoring PC through RS-422/485 communication, and those data are graphically shown on the PC monitor. Furthermore, the environmental circumstance can be monitored through the image processing system, and the emergency system can be operated under the condition of environmental incident such as electric power stoppage, DO deficiency, pump shut down and low level water etc.

• Biomedical Science Letters
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• v.21 no.3
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• pp.160-163
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• 2015

The effects of hypothermic treatment ($32^{\circ}C$) on recovery from ischemia are controversial because the precise mechanisms of hypothermia remain unclear. We demonstrated previously that hypothermia induces beta-catenin-interacting protein 1 (CTNNBIP1) gene expression in vitro. In this study, we evaluated the effects of various hypothermic conditions, including lithium chloride treatment, on CTNNBIP1 gene expression. The results show that short-term hypothermic treatment resulted in relatively higher CTNNBIP1 gene expression than that of a longer treatment. These findings indicate that hypothermia controls CTNNBIP1 gene expression, which may provide clues to develop treatments to recover from and diagnose ischemia.

• Journal of the Korean Institute of Intelligent Systems
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• v.19 no.3
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• pp.398-403
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• 2009

The recent trend of logistics demands for improved monitoring system of the inside of containers including current temperature and other environmental conditions. This paper presents an information processing technique with fuzzy logic that recognizes the current situations inside the target container and can be implemented on intelligent container systems. The ZigBee modules are used to collect information such as temperature, humidity, and shock inside the container in ubiquitous environment. The information processing system using fuzzy logic and the InTouch, one of SCADA(Supervisory Control and Data Acquisition) systems, is implemented to monitor the inside of the container and predict the emergency state.

• Journal of Chest Surgery
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• v.14 no.2
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• pp.140-143
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• 1981

Thymolipoma is extremely uncommon benign mediastinal tumor consisting of fatty and thymic tissue. Only 50 verified cases have been reported in the world literatures. This one case is the first reported example of surgically treated thymolipoma associated with spontaneous pneumothorax. A thirty-two year old male patient had been in good health until two days prior to admission, when he noted sudden dyspnea associated with an aching pain over the left precordium. The dyspnea and chest pain had become progressively worse. The physical examination revealed that left hemithorax was tympanic sound on percussion and absence of breathing sound on auscultation and point of maximal impulse was located on the 4th intercostal space at the left sternal border. Emergency closed thoracostomy was performed under the impression of tension type spontaneous pneumothorax of the left lung. After closed thoracostomy, point of maximal impulse was not changed inspire of full expansion of the left lung and chest X-ray was strongly suggested pericardial effusion or cardiomegaly which couldn`t account for by clinical course and hemodynamic evidence. EKG, echocardiogram, bronchofiberoscophy, bronchogram and diagnostic thoracentesis was performed. On Dec. 8, 1980, operation was performed under the impression of mediastinal tumor in the anterior mediastinum. At left posterolateral thoractomy, a large fatty mass, measuring 35 x 27 x 13 Cm in dimension and weighing 3350 gm, was resected and multiple bullae on the apicoposterior segment of the left upper lobe was resected and continuously sutured. The pathologic diagnosis of the fatty mass was thymolipoma. The postoperative course was uneventful and discharged in good general conditions.

• Journal of Chest Surgery
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• v.14 no.2
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• pp.135-139
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• 1981

Thymolipoma is extremely uncommon benign mediastinal tumor consisting of fatty and thymic tissue. Only 50 verified cases have been reported in the world literatures. This one case is the first reported example of surgically treated thymolipoma associated with spontaneous pneumothorax. A thirty-two year old male patient had been in good health until two days prior to admission, when he noted sudden dyspnea associated with an aching pain over the left precordium. The dyspnea and chest pain had become progressively worse. The physical examination revealed that left hemithorax was tympanic sound on percussion and absence of breathing sound on auscultation and point of maximal impulse was located on the 4th intercostal space at the left sternal border. Emergency closed thoracostomy was performed under the impression of tension type spontaneous pneumothorax of the left lung. After closed thoracostomy, point of maximal impulse was not changed inspire of full expansion of the left lung and chest X-ray was strongly suggested pericardial effusion or cardiomegaly which couldn`t account for by clinical course and hemodynamic evidence. EKG, echocardiogram, bronchofiberoscophy, bronchogram and diagnostic thoracentesis was performed. On Dec. 8, 1980, operation was performed under the impression of mediastinal tumor in the anterior mediastinum. At left posterolateral thoractomy, a large fatty mass, measuring 35 x 27 x 13 Cm in dimension and weighing 3350 gm, was resected and multiple bullae on the apicoposterior segment of the left upper lobe was resected and continuously sutured. The pathologic diagnosis of the fatty mass was thymolipoma. The postoperative course was uneventful and discharged in good general conditions.