• Proceedings of the KIEE Conference
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• 1994.07a
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• pp.582-584
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• 1994

A sinusoidal rotatory chair system using a self-tuning and following control by a fuzzy was designed to evaluate the vestibular function and to apply to a robot driving power system. The experimental results by the sinusoidal rotatory chair system were pretty good and whitch had smaller then ${\pm}210$ pulse error on the ${\pm}810^{\circ}$ sinusoidal rotation at 0.12 Hz by using a 850W DC servo motor. As a results, the sinusoidal rotatory chair system may be useful to evaluate the vestibular function in the field of medicine, and it can be used to robotics or a numerical control system (NC) on the industry if the the obtained control method and the system are adapted for a channel.

• Proceedings of the KIEE Conference
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• 1995.11a
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• pp.284-286
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• 1995

The most common for starting a single phase induction motor is to install a starting condenser and a centrifugal switch in series with the auxiliary winding. Though this method is simple, life of single phase induction motor is short because of malfunction of a starting condenser and a centrifugal switch and efficiency improvement has limitation. In this paper, the starting characteristics of SPIM is improved by voltage and phase control strategy of auxiliary winding in removing a starting condenser and a centrifugal switch. Finally, the excellent starting performance of SPIM is shown through simulation and experimental results.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.2 s.245
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• pp.105-111
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• 2006

This paper describes a Neural Network based PID control scheme for pneumatic NC axes. Pneumatic systems have inherent nonlinearities such as compressibility of air and nonlinear frictions present in cylinder. The conventional PID controller is limited in some applications where the affection of nonlinear factor is dominant. A self-excited oscillation method is applied to derive the dynamic design parameters of linear model. The gains of PID controller are determined using a self tuning scheme. The experiments of a trajectory tracking control using the proposed control scheme are performed and a significant reduction in tracking error is achieved by comparing with those of a PID control.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.652-657
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• 2003

A wind-tunnel experiment is carried out to examine the applicability of a new passive device, wake disrupter, to flow over a model vehicle for drag reduction. The wake disrupter is a small-size rectangular body attached to a part of the trailing edge of the model vehicle, designed to perturb an essentially two-dimensional nature of wake. A pair of wake disrupter is mounted on the mid-span at the upper and lower trailing edges. From a parametric study about the size of wake disrupter, it is found that the optimum disrupter increases the base pressure by about 20%. Large eddy simulation is also conducted to confirm the experimental result, and shows that the wake is indeed disrupted by the present device.

• Journal of Korean Foot and Ankle Society
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• v.20 no.1
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• pp.43-45
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• 2016

Development of a pseudoaneurysm around the ankle is an uncommon complication after surgery. We experienced a case of a pseudoaneurysm, which developed from the anterior tibial artery. A 44-year-old woman had sustained painful swelling of her right ankle after the removal of implants for a distal fibular fracture. The pseudoaneurysm was confirmed by ultrasonography and angiography. The patient was treated with an intervention using a coil and recovered without further complaints. This case report aims to increase the awareness of this complication with review of literature.

• Journal of Energy Engineering
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• v.16 no.1 s.49
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• pp.1-6
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• 2007

The purpose of this study was to investigate the reduction of exhaust gas temperature in a LPG engine that had been converted from a diesel engine. A conventional diesel engine was modified to a LPG (Liquefied Petroleum Gas) engine by replacing the diesel fuel injection pump with a LPG fuel system. The research was performed by measuring the exhaust gas temperature upon varying spark ignition timing, airfuel ratio, compression ratio, and different compositions of butane and propane. Engine power and exhaust temperature were not influenced by various butane/propane fuel compositions. Finally, among the parameters studied in this investigation, spark ignition timing is one of the most important in reducing exhaust gas temperature.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.2930-2932
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• 2000

In this paper. a robust gesture recognition system is designed and implemented to explore the communication methods between human and computer. Hand gestures in the proposed approach are used to communicate with a computer for actions of a high degree of freedom. The user does not need to wear any cumbersome devices like cyber-gloves. No assumption is made on whether the user is wearing any ornaments and whether the user is using the left or right hand gestures. Image segmentation based upon the skin-color and a shape analysis based upon the invariant moments are combined. The features are extracted and used for input vectors to a radial basis function networks(RBFN). Our "Puppy" robot is employed as a testbed. Preliminary results on a set of gestures show recognition rates of about 87% on the a real-time implementation.

• Korean Journal of Computational Design and Engineering
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• v.15 no.3
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• pp.222-233
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• 2010

Developed in this research is a TP (tangible prototyping) system, which consists of two modules; (1) a virtual reality model to evaluate the functions and appearance of the product, and (2) a haptic device to emulate tactile and kinesthetic properties of mechanical dial knobs. As an example, a washing machine is modeled using a commercial CAD system and transformed in VRML and X3D formats. Some dynamic behaviors and kinematic characteristics are programmed using X3D script and Java. Various haptic behaviors of the dial are generated by modulating torque profile according to the rotation angle. A torque profile measuring system is developed to evaluate the behaviors of the haptic dial physically. Haptic sensibility evaluations are accomplished using the TP by semantic differential method.

• Journal of the Korea Society of Computer and Information
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• v.9 no.3
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• pp.127-133
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• 2004

This study was carried out develope a temperature control system of temperature control by used K-thermocouple. This system was producted a stable voltage regulator 22Bit of digital converter and 22Bit of resolution. It was producted a micro voltage of 25 times amplification and controlled a DC0.1V~DC4.7V within 0～120$0^{\circ}C$. We designed block-diagram of hardware and software by PIC16C74 in a micro-controller, we are made up of a VFD function and can be used interface of a power block.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.05a
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• pp.235-242
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• 2012

In recently constructed building, It has become fashionable again that the heavy external skin system such as a Stone Finished Envelope. There are Squared Steel Pipe Methods, C-Shaped Steel Pipe Methods, and Aluminum Beam Methods in the structure of a heavy external skin system. The Aluminum Beam Methods is often misunderstood as a Plane Truss Structure, but this method is not appropriate to be called to a truss structure but a beam methods. The Aluminum Beam Methods is the most Eco-friendly methods in terms of Quality assurance, Efficiency, Safety, Construction period, Durability, and Recyclability. And this Methods is also very appropriate in considering the point of Energy conservation, Waste reduction, Long-life architecture, Replacement parts, Environmental protection, Public efficiency, and Building demolition.