• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.916-919
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• 1996

An real-time active beacon localization system for mobile robots is developed and implemented. This system permits the estimation of robot positions when detecting light sources by PSD(Position Sensitive Detector) sensor which are placed sparsely over the robot's work space as beacons(or landmarks). An LSE(Least Square Estimation) method is introduced to calibrate the internal parameters of a model for the beacon and robot position. The proposed system has two operational modes of position estimation. One is the initial position calculation by the detection of two or more light sources positions of which are known. The other is the continuous position compensation that calculates the position and heading of the robot using the IEKF(Iterated Extended Kalman Filter) applied to the beacon and dead-reckoning data. Practical experiments show that the estimated position obtained by this system is precise enough to be useful for the navigation of robots.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10a
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• pp.609-614
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• 2000

This paper is an experimental study of the normal strength concrete beam and high strength concrete beam for the analysis of bending and shear behavior. In building structure, the story height can be minimized by providing openings in beams which serves for the utility equipments passing through. The dead space in false ceiling increase construction cost, the good ceiling system such as beam with opening give to economical merits because of a substantial reduction in materials and construction cost. For the analysis on the mechanical behavior of the reinforced high strength and normal strength concrete beams with circular opening in the web, the stress concentration of the circular opening, crack pattern and reinforcing methods were studied. Twenty test pieces with different reinforcing methods and difference concrete strength were tested and their resisting forces and load deflection curves were defined in this study.

• Proceedings of the KIPE Conference
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• 1999.07a
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• pp.274-277
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• 1999

The paper describes a implementation of space vector pulse-width modulation (SVPWM) voltage source inverter using Field Programmable Gate Array(FPGA) for a induction motor control system. The implemented chip is included logic circuits for SVPWM, dead time compensation and speed detection using Quick Logic, QL16X24B. The maximum operating frequency and delay time can be set to 110MHz and 6 nsec. The designed FPGA for SVPWM can be incorporated with a digital signal processing to provide a simple and effective solution for high performance voltage source inverter drives. Simulation and Implementation results are shown to verify the usefulness of FPGA as a Application Specific Integrated Circuit(ASIC) in power electronics applications

• Journal of Institute of Control, Robotics and Systems
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• v.10 no.6
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• pp.529-536
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• 2004

Autonomous navigation of an indoor mobile robot using the global ultrasonic system is presented in this paper. Since the trajectory error of the dead-reckoning navigation grows with time and distance, the autonomous navigation of a mobile robot requires to localize the current position of the robot, so that to compensate the trajectory error. The global ultrasonic system consisting of four ultrasonic generators fixed at a priori known positions in the work space and two receivers on the mobile robot has the similar structure with the well-known satellite GPS(Global Positioning System), and it is useful for the self-localization of an indoor mobile robot. The EKF(Extended Kalman Filter) algorithm for the self-localization is proposed and the autonomous navigation based on the self-localization is verified by experiments.

• Journal of Institute of Control, Robotics and Systems
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• v.3 no.1
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• pp.46-51
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• 1997

The optimal control of a continuous process has been performed using genetic algorithms(GAs). GAs are robust and easily applicable for complex and highly nonlinear problems. We introduce the heuristics 'dynamic range' which reduces the search space dramaticaly keeping the robust search of GAs. GAs with dynamic range show the better performance than SQP(Successive Quadratic Programing) method which converges to a local minimum. The proposed methology has been applied to the optimal control of the continuous MMA-VA copolymerization reactor for the production of the desired molecular wieght and the composition of VA in dead copolymer.

• Archives of Plastic Surgery
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• v.33 no.3
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• pp.303-307
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• 2006

No one technique provides an optimal outcome for all body contouring patients. There are many surgical options for abdominoplasty. Among these, this abdominoplasty without undermining consists of liposuction around abdominal subcutaneous fatty tissue, excision of lower abdominal flap. The procedure allows aggressive thinning and sculpting of abdominal flap. This operation minimizes the dead space, which often leads to postoperative complications, and preserves neurovascular supply to the abdominal skin. From 1999 to 2004, 18 patients underwent the abdominoplasty without undermining, resulting in high satisfaction rates with no significant complications, such as, pulmonary embolism and deep vein thrombosis. Patients could return to normal activity within a week. This abdominoplasty without undermining is an effective and safe alternative with low complication rate and enhances aesthetic results compared to traditional abdominal surgery.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.61 no.1
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• pp.47-54
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• 2012

This paper presents implementation of SVPWM technique for three phase Voltage Source Inverter using FPGA. Software-based vector-control calculations much this drawback, in order to improve the hardware-vector-control tries. Without the need for additional software, vector control algorithm is designed to be modular SOPC, and DSP will reduce most of the operations. In this paper, the SVPWM that using HDL for the AC motor vector control algorithm level, and the dead time part and the speed control in order to controled a speed detector and designed in the form of modules. Then ALTERA corporation Cyclone III series EP3C16F484 can be verified by implemented.

• Proceedings of the Korean Information Science Society Conference
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• 2001.04b
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• pp.31-33
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• 2001

고비용의 공간 연산을 수행해야 하는 공간 질의 처리는 여과-정제의 2단계 처리가 일반적이다. 그러나, 2단계 색인 방법은 여과율이 좋지 못한 단점이 있으므로, 최근 다단계 여과 과정이 많이 연구되고 있다. 다단계 여과 과정은 1차 여과된 객체에 대하여 더욱 정밀한 필터를 적용함으로써 후부 객체 수를 줄이는 방법으로 접근하고 있으나, 여러 번의 여과 단계를 거치므로 수행 시간이 길어지고 추가 정보유지로 인한 저장 공간 낭비 등의 단점이 있다. 본 논문에서는 전체 공간 영역을 격자로 분할하고, 객체를 격자 위에 구성하는 2단계의 공간 색인 방법을 제안한다. 제안된 색인 방법은 Dead Space의 크기를 줄이고, 한 번의 여과 과정으로 높은 여과율을 갖는다.

• Tunnel and Underground Space
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• v.5 no.1
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• pp.48-56
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• 1995

Recently, most of the underground excavation works are adopting heavy duty mobile diesel equipments which have outstanding merits in view of efficiency. However, these equipments are causing hygienic problems to the workers due to the various hazardous exhaust contaminants. Considering that there are always dead end workings in underground excavation sites, it is very important how to supply enough airflow to the workings to dilute diesel exhaust contaminants. This paper introduced the theoritical mechanism and actual trends of exhaust contaminants of diesel equipments under operation at local mines and suggested the design method of intake air volume in underground excavation workings using diesel equipments.

• Journal of Veterinary Clinics
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• v.21 no.1
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• pp.58-61
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• 2004

A 5-year old female shih-tzu referred to the veterinary Teaching Hospital, College of Veterinary Medicine, Konkuk University. The patient was presented with a mass of ventral to pubic region and intraperineal region. CBC, chemistry, x-ray, fine needle aspiration, biopsy and MRI was performed. The dog was definitively diagnosed as lipoma based on cytologic and histopathologic examination. In order to remove the mass, an approach with two direction was made. First, intraperineal region was removed about 40%, and then ventral to pubic was removed the remainder. And inserted penrose drain for obliterate dead space to prevent the accumulation of serous discharge. The dog is clinically normal and being monitored for development of any abnormal signs for the time being. In this case, diagnostic MRI was very useful procedure. it revealed accurate location of a lipoma and useful manner for decision of surgical approach to remove.