• Journal of Power Electronics
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• 제16권3호
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• pp.840-848
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• 2016

A primary-side regulation AC-DC converter operating in the PFM (Pulse Frequency Modulation) mode with a high precision output current is designed, which applies a novel inductance compensation technique to improve the precision of the output current, which reduces the bad impact of the large tolerance of the transformer primary side inductance in the same batch. In this paper, the output current is regulated by the OSC charging current, which is controlled by a CC (constant current) controller. Meanwhile, for different primary inductors, the inductance compensation module adjusts the OSC charging current finely to improve the accuracy of the output current. The operation principle and design of the CC controller and the inductance compensation module are analyzed and illustrated herein. The control chip is implemented based on a TSMC 0.35μm 5V/40V BCD process, and a 12V/1.1A prototype has been built to verify the proposed control method. The deviation of the output current is within ±3% and the variation of the output current is less than 1% when the inductances of the primary windings vary by 10%.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권12호
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• pp.5998-6016
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• 2017

In thin-film transistor liquid-crystal displays (TFT-LCDs), which are most commonly used in mobile devices, the backlight accounts for about 70% of the power consumption. Therefore, most low-power-related studies focus on realizing power savings through backlight dimming. Image compensation is performed to mitigate the visual distortion caused by the backlight dimming. Therefore, popular techniques include pixel compensation for brightness recovery and contrast enhancement, such as histogram equalization. However, existing pixel compensation techniques often have limitations with respect to blur owing to the pixel saturation phenomenon, or because contrast enhancement cannot adequately satisfy the human visual system (HVS). To overcome these, in this study, we propose a novel dimming technique to achieve both power saving and HVS-awareness by combining the pixel compensation and histogram specifications, which convert the original cumulative density function (CDF) by designing and using the desired CDF of an image. Because the process of obtaining the desired CDF is customized to consider image characteristics, histogram specification is found to achieve better HVS-awareness than histogram equalization. For the experiments, we employ the LIVE image database, and we use the structural similarity (SSIM) index to measure the degree of visual satisfaction. The experimental results show that the proposed technique achieves up to 15.9% increase in the SSIM index compared with existing dimming techniques that use pixel compensation and histogram equalization in the case of the same low-power ratio. Further, the results indicate that it achieves improved HVS-awareness and increased power saving concurrently compared with previous techniques.

• 한국조리학회지
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• 제10권4호
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• pp.31-49
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• 2004

Nowadays, a knowledge management becomes more important as it recognizes and utilizes a industrial knowledge as a significant sources for the improvement of enterprise competitiveness. Moreover, a industrial value tends to be evaluated by a knowledge value. In this study, influencing factors (processes, compensation system, leadership and information technology) on the knowledge sharing for strategies in foodservice Enterprise were investigated. For processes, it was important that the sharing and collecting factors for restaurants in hotel, the knowledge sharing and collecting for family-restaurants, the knowledge utilization and collecting for fast-food restaurants and the knowledge utilization and sharing for special restaurants. In compensation system, both mental and physical compensation were not related with the knowledge sharing in hotel-restaurants. On the other hands, the knowledge sharing in family-restaurants, fast-food restaurants and special restaurants was highly affected by the mental compensation, which indicated that food-service. Enterprise should lay emphasis on mental compensation than physical compensation. In industrial cultures, the influencing factors on the knowledge sharing were rational culture and progressive culture for restaurants in hotel and fast-food restaurants, and for special restaurants and family- restaurants, respectively. The ordering leadership was important factor for restaurants in hotel, fast-food restaurants and family-restaurants, while the knowledge sharing in special restaurants was more influenced by the supporting leadership. For information technology, it was important that the information utilization for restaurants in hotel, special restaurants and fast-food restaurants, and both information utilization and ability for family-restaurants.

• 정보보호학회논문지
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• 제22권2호
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• pp.367-377
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• 2012

(개인정보 침해사고의 위자료 산정) 개인정보의 상업적 가치가 증대되면서 불법적 거래나 유통, 유 노출사고 등의 개인정보 침해사고가 발생하고 있고 개인정보침해에 대한 위자료 산정이 침해사고에 대한 해결책이 되고 있다. 그러나 개인정보는 비시장재이며 교환가격이 존재하지 않으므로 위자료의 정량적 산정에는 어려움이 있다. 이에 대한 대안으로 본 연구에서는 시장에서 거래되지 않아 가치에 대한 정보를 얻을 수 없는 개인들의 가치평가를 추정하기 위해 CVM을 이용하여 유형별 WTA를 추정하였다. 또한, 일본의 JNSA JO 모델을 적용하여 한국에 부재한 위자료산정의 정형화된 모델에 관한 연구를 시도했다. 본 연구는 단순히 위자료 산정의 접근 방안을 제시한 것에 그치는 것이 아니라 개인정보의 가치를 측정함으로써 기업이나 조직들에게 개인정보의 중요성에 대한 경각심을 일깨워줄 수 있을 것이다.

• 소성∙가공
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• 제21권7호
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• pp.432-440
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• 2012

In this article, the design of the flexible forming process considering die shape compensation using an iterative over-bending method based on numerical simulation was conducted. In this method, the springback shape obtained from the final step of the first forming simulation is compared with the desired objective shape, and a shape error is calculated as a vector norm with three-dimensional coordinates. The error vector is inversely added to the objective surface to compensate both the upper and lower flexible die configurations. The flexible die shapes are recalculated and the punch arrays are adjusted according to the over-bent forming surface. These iterative procedures are repeated until the shape error variation converges to a small value. In addition, experimental verification was conducted using a 2000-kN flexible forming apparatus for thick plates. Finally, the configuration of the prototype obtained from the experiment was compared with the numerical simulation results, which had springback compensation. It is confirmed that the proposed method for compensating for the forming error could be used in the design of flexible forming of thick-curved plates.

• 한국정밀공학회지
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• 제21권4호
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• pp.95-102
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• 2004

It is necessary to improve the exactness and adaptation of the working environment in the intelligent robot system. The vision sensor have been studied for this reason fur a long time. However, it is very difficult to perform the camera and robot calibrations because the three dimensional reconstruction and many processes are required for the real usages. This paper suggests the image based visual servoing to solve the problem of old calibration technique and supports OLP(Off-Line-Programming) path compensation. Virtual camera can be modeled from the real factors and virtual images obtained from virtual camera gives more easy perception process. Also, Initial path generated from OLP could be compensated by the pixel level acquired from the real and virtual, respectively. Consequently, the proposed visually assisted OLP teaching remove the calibration and reconstruction process in real working space. With a virtual simulation, the better performance is observed and the robot path error is calibrated by the image differences.

• 한국중재학회지:중재연구
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• 제18권3호
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• pp.139-163
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• 2008

The Collective Dispute Mediation was introduced to Korea with complement the Verbandsklage which was said to be poor at monetary compensation for consumers' damages. and The Collective Dispute Mediation also seems very likely to the class action, but one can resolve the dispute before filing a law suit under the Collective Dispute Mediation. The validity of the Collective Dispute Mediation is the same as the "settlement in court". After reaching the Collective Dispute Mediation, one may have a right to ask the compulsory execution. Under the Collective Dispute Mediation the damaged party must take part directly in the dispute, because the Collective Dispute Mediation is also included in the dispute resolution. Therefore a problem that how can the damaged consumer, who do not directly take part in the dispute process, get the remedy alternatively may arise. However, this problem is solved by Compensation Plan Letter which is described in the "Framework Act on Consumer". By the Compensation Plan Letter, the person who do not directly take part in the dispute process can be remedied ex post facto(Article 68). This thesis is study on The Function and Task of Collective Dispute Mediation in the Framework Act on Consumer in our state.

• 대한기계학회논문집A
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• 제21권2호
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• pp.189-198
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• 1997

This paper presents development of a practical tool deflection compensation system in order to reduce the machining error from the tool deflection compensation system in order to reduce the machining error from the tool deflection in the end-milling process. The devised system is a tool adapter which includes 1-axes force sensor for detecting tool deflection and 2-axes tool tilting device for adjusting tool position through computer interface on line process. Experimental in investigations for typical shaped workpieces representing various end milling situations are performed to verify the ability of the system to suppress the surface errors due to tool deflections. With the system, it is possible to get precise machining surface without any excessive machining error due to increased cutting force in more productive machining conditions.

• 농촌계획
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• 제21권1호
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• pp.41-50
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• 2015

In this study, the relative importance for the perception of managers on the comprehensive rural village development projects was evaluated using the AHP method. The fields for evaluation were 4 fields including human relationships, working conditions, work compensation and work burnout. Also, the relative importance for the perception of managers and priority order were analyzed through 15 evaluation items. The analysis result shows that the human relationships among 4 fields were regarded as the most important field, followed by work compensation, working conditions and work burnout. Also, the relationship with the chairperson for the human relationships, continuity of employment for the working conditions, salary for work compensation, and mental stress for work burnout were considered respectively as the most important item. Also, salary among all evaluation items was considered as the most important item for the relative importance, followed by continuity of employment, relationship with village residents and mental stress. However, work load, consulting firms, impersonal treatment and the relations between the administration showed relatively low importance and priority order. It is considered that this analysis result will be used as important preliminary data for establishing the role of manager in the comprehensive rural village development project.

• 소성∙가공
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• 제29권4호
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• pp.188-193
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• 2020

Piping work of large ships or offshore plants is often done in a narrow and confined space, requiring precise bending and safety. In order to realize an accurate bending angle, it is very important to predict and correct a deformation that may be caused by elasticity in the bending process, that is, an angular deviation due to springback. Therefore, by using CAE analysis to develop a correction angle model for springback based on multiple tube bending angles and using trend line data derived from this correction angle model, at bending the tube as the diameter of the base former and the tube outer diameter change, the springback compensation angle at any angle can be obtained. In this study, the bending mechanism was analyzed to increase the bending precision, and a correction angle model was developed and a trend line was derived in consideration of springback occurring in the bending process. In order to derive a more accurate and reliable trend line, a tube tensile test was performed, and the reliability of the corrected angle trend line was verified by comparing the bending angle measurement and analysis results with a 3D scanner.