• Toxicological Research
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• 제11권1호
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• pp.103-108
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• 1995

Rat renal proximal tubule suspension was prepared from adult male Sprague Dawley rat (250-300g) by mechanical (non-enzymatical) method and evaluated as a pontential model for mechanistic studies and early screening of nephrotoxicity, using anionic antibiotics (cephaloridine). Cephaloridine (CPL) produced an increase in LDH release into media. This release results from decrease a proximal tubule cell viability and subsequently increase the permeability of cell viability and subsequently increase the permeability of cell membrane. Since loss of intracellular potassium and ATP into media is the sign of disruption of cell membrane, especially basolateral membrane (BLM), CPL induced proximal tubule cell compromise also appear be associated with BLM, maybe $Na^+-K^+$ ATPase. Also seen was significant depression in brush border membrane (BBM) ALP activity and no significantly increase in BBM GGT activities. The inhibition of typical anion, PAH accumulation (especially, CPL 5 mM) and cation, TEA (especially, 4hours incubation) were seen dose dependently. This is because of CPL accumulation in renal proximal tubule and increase of cytotoxicity.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.2073-2074
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• 2011

In this study, an algorithm for diagnosis of dc motor with winding open fault is suggested. A dc motor used in this paper, is consisted of a permanent magnet field stator, double 16-turn series winding rotating armature with 12-slot, brush and 12-commutator, etc. A current signal of dc motor which has brushes and commutatorswas considered for fault diagnosis. By commutation, this current signal shows different wave form according to the fault condition of the motor. In this study, operation of the data was easily through simplification of the current signal by the signal processing. Computation method is presented reference value($C_{dv}$) for diagnosis of winding open fault and verified through experiments that can be diagnosed using the reference value($C_{dv}$).

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1995년도 추계학술대회 논문집
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• pp.1173-1176
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• 1995

We design and analyze two type stators for brushless DC linear motors by the experiment and the computational analysis. For a U-shape stator, the maximum manetic flux density by the finite element method(FEM) is large than that by the experiment by 1.0~2.2%. The result by the FEM is so accurate that it can be applied to the geometric design for the optimization. To increase the maximum magnetic flux density, we suggest an improved stator and analyze it by the 3-D and 2-D models. The maximum magnetic flux density of the improved stator is large than that of the U-Shape stator by 2.7%. Considering the size of the improved stator and maximum magnetic flux density, we determine that the optimized thickness is 5mm for a given specification.

• 한국안전학회지
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• 제19권4호
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• pp.80-85
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• 2004

Electromagnetic interference(EMI) shielding characteristics of composite filled with Cu flake and carbon brush powder as hybrid conductive filler and EAF slag have been studied. The coaxial transmission line method of ASTM D4935-99 was used to measure the EMI Shielding effectiveness of composites as formulation in frequency rage $100\~1,000MHz$ The SE also increases with the increase in flier loading. The hybrid filler filled composites show higher SE compared to that of only Cu flake. The correlation between SE and conductivity of the various composites is also discussed. The results indicate that the composites having higher filler loading$({\geq}40wt.\%)$ can be used for the purpose of safety materials to protect hazardous electromagnetic interference.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 심포지엄 논문집 정보 및 제어부문
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• pp.69-71
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• 2005

DC servo motors have a defect that they need a periodical maintenance because of a brush commutation and also they have a difficulty at high speed operation. In this reason, the use of AC Servo motors are increasing these days. In this paper, a proposed neuro observer is applied to speed control of AC servo motor. The proposed observer complement a problem that occur from increase of gain of High-gain observer in proportion to the square number of observable state variables. And also, the proposed observer can tune the gain obtained by differentiating observational error automatically by using the backpropagation training method to stabilize the observational speed. The excellence and feasibility of the proposed observer is proved by making a comparison test between the proposed observer and the others applied to the same AC servo motor.

• 대한가정학회지
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• 제27권2호
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• pp.1-19
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• 1989

Dress is an expressive art form which involves a human activity; utilizes techniques under sufficient technical control that results in the production of typical forms on the basis of aesthetic standards. This study was conducted to clarify a relationship of Impressionism and it's image in dress-Bustle style. Artists such as Manet, Renoir, Cezanne, Gogh, Gauguin, and Rodin were reviewed. Impressionism was a method of painting that consists in repoducing an impression exactly as it is experienced from contemplation nature. The Impressionists used a technique of separate, fragmented brush strokes and pure prismatic colore, aiming at rendering changing effects of light. Fashion designers such as Charles Worth, Givency, Cardin, Ungaro, and Lacroix were examined. Throughout their fashions, they focused on the naturalism of feminine and seductive image-the touch of Vegetable Venus depicted on the paintings of Manet and Renoir; expressed "unmitigated sexiness" in various forms of Bustle sytle creating a seductive beauty, revealing body contour, breast and legs, and using a fragmented motif and flowers with vivid color.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.315-316
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• 2006

A new cleaning robot system for live-line tension insulator string was developed to prevent an insulator failure, which can have severe effects on national security as well as national industry and economy. The robot moves along the insulator string using the clamps installed on its two moving frames. Especially, unlike the existing cleaning robots using jets of water or water/air, the robot system adopts dry cleaning method using a rotating brush and a circular motion guide. This robot system has control architecture consisting of a master control unit and two slave control units. We confirmed its effectiveness through experiments.

• 수산해양기술연구
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• 제30권2호
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• pp.97-108
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• 1994

The DC Servo Motor has been used as an actuator in automatic control fields because of the good response and the control easiness nevertheless it has some disadvantage such as spark at the brush. Recently, along with the fast development of semiconductor industries, the digital control scheme is increasing in comparison with analog control because of the strength against noise and the accuracy. In this paper, authors proposed a combined control algorithm, which is mixed Modified Minimum Time Position Control(MMTPC) and PI control algorithm. for minimum time position control of DC Servo Motor by the one-chip microcontroller. The proposed control algorithm showed the fast response and offset-free. The validity of the proposed method comparing with the VSS control is proved by the response experiments.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2005년도 전력전자학술대회 논문집
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• pp.39-41
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• 2005

In this paper, a study on the controller for high speed PMSM (Permanent Magnet Synchro-nous Motor) is described. PMSM can be driven over 50,000 rpm because it has no brush and commutator structure. It also has less EMI noise and easy cooling structure compare to the other motors. The controller was designed to have a capability to drive 20kw, 42,000rpm high speed motor system. A senseless vector control method was studied based on d-q conversion theory to have a high driving efficiency. The control board was designed using TMS320C33 and the performance was verified by experimental results on driving the inverter and motor system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 B
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• pp.738-740
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• 2000

This paper presents the design process for series wound DC motor with the brush by using the experimental data of a tested motor. The design parameters calculated from the experimental data are friction loss. windage loss and contact resistance of brushes. The characteristic analysis of the designed motor is performed and then the proposed method is verified by comparing with experimental result.