• 한국안전학회지
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• 제8권4호
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• pp.101-106
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• 1993

The streaming current of insulating oil increases with increasing oil velocity and oil amount, A contact potential difference as an energetic state exits in the polymer thin film, both sides of which are contacted by two different metals having different work functions. Accordingly, the potential difference may be a cause for the short circuited transient current flowing through the external circuit. The polymers are electrificated as the electric field Is supplied, and the currents flow with increasing temperature.

• 한국전산구조공학회논문집
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• 제24권5호
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• pp.577-588
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• 2011

본 논문은 복합 불연속면을 갖는 포텐셜 문제의 해석을 위해 확장된 MLS(Moving Least Squares) 차분법을 제시한다. 계면경계를 따라 해(solution)와 수직방향, 접선방향 미분들이 모두 불연속 특이성을 나타내는 복합 불연속면을 묘사하기 위해 계단함수, 쐐기함수, 가위함수와 같은 불연속 특이함수를 추가하여 기존의 MLS 차분법을 개선했다. 계면경계조건은 기지의 조건으로서 지배방정식의 이산화과정에서 추가의 미지계수를 발생시키지 않는다. 포아송 방정식 형태의 지배미분 방정식을 풀기 위해 내부영역과 경계에 절점을 배치하고 차분식을 구성한다. 차분식을 조립한 계 방정식을 직접 풀기 때문에 계산효율성이 매우 우수하다. 수치예제는 제시된 해석기법의 우수성을 잘 보여주며, 균열전파, 이동경계, 상호작용 문제 등 다양한 불연속 문제로의 확장이 기대된다.

• 한국작물학회지
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• 제50권1호
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• pp.28-31
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• 2005

To identify salt-tolerance characteristics of corn seedling was treated in solution of 0, 50 and 100 mM NaCl of hydroponic cultivation. In photosynthesis of corn seedling, there was no large difference between 50mM and 0 mM NaCl solution, however, in 100 mM NaCl solution, the tolerance gradually decreased to $76\%,\;49\%,\;and\;31\%$ after one day, four days, and seven days, respectively, in comparison to 0 mM NaCl solution. Osmotic potential of corn in seedling period was significantly decreased with increasing saline level, however, free proline content in the plant on the ground was significantly increased with increasing saline level and with the lapse of time. In terms of correlation among major characteristics, there was a highly significant positive difference between osmotic pressure potential and photosynthesis, However, highly negative correlation was found between osmotic pressure potential and free proline content. In addition, it was expected that young seedling of corn with saline tolerance may be utilized in the transplantation in salt-accumulated land. Based on above-shown result, in terms of saline tolerance of Chalok-2 variety, growth suppression was serious with 100mM NaCl solution. However, growth was expected that seedling growth would be favorable under 50 mM NaCl solution.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.298-298
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• 2013

Finding renewable and clean energy resources is essential research to solve global warming and depletion of fossil fuels in modern society. Recently, complex harvesting of energy from multiple sources is available in our living environments using a single device has become highly desirable, representing a new trend in energy technologies. We report that when simultaneously driving the fusion and composite cells of two or more types, it is possible to make an affect the other cells to obtain a greater synergistic effect. To understand the coupling effect of photovoltaic and piezoelectric device, we fabricate the serially integrated hybrid cell (s-HC) based on organic solar cell (OSC) and piezoelectric nanogenerator (PNG). The size of increased voltage peaks when OSC and PNG are working on is larger than the case when only PNG is working. This voltage difference is the Voc change of OSC, not the voltage change of PNG and current density difference between these two cases is manifested more clearly. When the OSC and PNG are working in s-HC at the same time, piezoelectric potential (VPNG) is generated in ZnO and theoretical total voltage is sum of voltage of an OSC (VOSC) and VPNG. However, electrons from OSC are influenced by piezoelectric potential in ZnO and current loss of OSC in whole circuit decreases. As a result, VOSC increases temporarily. Current shows the similar behavior. PNG acts a resistance in the whole circuit and current loss occurs when the electrons from OSC pass through the PNG. But piezoelectric potential recover current loss and decrease the resistance of PNG. Our PNG can maintain piezoelectric potential when the strain is held owing to the LDH layer while general PNG cannot maintain piezoelectric potential. During the section that strain is held, voltage enhancement effect is maintained and same effect appeared even turn off the light. Actually at this time, electrons in ZnO nanosheets move to LDH and trapped by the positive charges in this layer. After this strain is held, piezoelectric potential of ZnO nanosheets is disappeared but potential difference which is developed by negative charge dominant LDH layer is remained. This potential acts similar role like piezoelectric potential in ZnO. Electrons from the OSC also are influenced by this potential and the more current flows.

• 한국태양에너지학회 논문집
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• 제35권5호
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• pp.57-65
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• 2015

The Potential Induced Degradation(PID) in PV module mainly affected by various performance conditions such as a potential difference between solar cell and frame, ambient temperature and relative humidity. The positive charges as sodium ions in front glass reach solar cell in module by a potential difference and are accumulated in the solar cell. The ions accelerate the recombination of generation electrons within solar cell under illumination, which reduces the entire output of module. Recently, it was generally known that PID generation is suppressed by controlling the thickness of SiNx AR coating layer on solar cell or using Sodium-free glass and high resistivity encapsulant. However, recovery effects for module with PID are required, because those methods permanently prevent generating PID of module. PID recovery method that voltage reversely applies between solar cell and frame contract to PID generation begins to receive attention. In this paper, PID recovery tests by using voltage under various outdoor conditions as humidity, temperature, voltage are conducted to effectively mitigate PID in module. We confirm that this recovery method perfectly eliminates PID of solar cell according to repeative PID generation and recovery as well as the applied voltage of three factors mainly affect PID recovery.

• 중국학논총
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• 제72호
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• pp.25-45
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• 2021

This study aims to select eight books to see if "potential complement" is sufficiently acquired and properly used in Chinese conversation textbooks, explore the reasons and problems of learners' errors through analysis, and briefly suggest textbook compilation and teaching. Twelve criteria were established and analyzed, including the concept and format of "potential complement", layout order, location of objects, three types of forms, distinction from auxiliary verb "能" and distinction between "能+V+結果補語". Some of the results of the study are simply as follows. All eight textbooks focus only on "possibility," missing an important part of "the impact of objective conditions" that the term "potential complement" does not contain. This is certainly enough to cause confusion for learners. A poor understanding of the concept of "potential complement" results in identifying it with the possible auxiliary verb "能", and incorrect mixing because it does not know exactly what the difference is. Most of the textbooks compiled in China place a high importance on "potential complement". This means that Chinese people often use "potential complement" in real life. on the other hand relatively Korean textbooks do not deal with "potential complement" relatively importantly.

• 대한전기학회논문지:시스템및제어부문D
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• 제55권7호
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• pp.319-326
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• 2006

This paper proposes a novel fault-tolerant gait for Quadruped robots using energy stability margins. The previously developed fault-tolerant gaits for quadruped robots have a drawback of having marginal stability margin, which may lead to tumbling. In the process of tumbling, the potential energy of the center of gravity goes through a maximum. The larger the difference between the potential energy of the center of gravity of the initial position and that of this maximum, the less the robot tumbles. Hence this difference of potential energy, dubbed as Energy Stability Margin (ESM), can be regarded as the stability margin. In this paper, a novel fault-tolerant gait is presented which gives positive ESM to a quadruped robot suffering from a locked joint failure. Positive ESM is obtained by adjusting foot positions between leg swing sequences. The advantage of the proposed fault-tolerant gait is demonstrated in a case study where a quadruped robot with a failed leg walks on a even slope.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.1315-1317
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• 2008

The plasma display panel is an image expression display using gas discharge. However gas discharge characteristics vary with temperature. Furthermore, the potential difference among three electrodes appears in sustain period due to external applied voltages. It affects to the wall charge state accumulated on the electrodes. This research aims at identifying that the discharge characteristics depend on the potential difference and temperature. The results show that the wall charge loss increases with increase of the number of applied pulse during sustain period and it severely appears at high temperature.

• 한국전기전자재료학회논문지
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• 제22권6호
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• pp.526-531
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• 2009

In this paper, the safety for passengers of composite car-body against lightning strikes was analyzed by the application of an impulse generator which can produce impulse current up to 50 kA with 8/$20{\mu}s$ waveform. Potential difference on inside surface of the car-body was measured as a safety parameter for the passengers against lightning strikes. The potential difference between 20 em distant was 175 V at 37.67 kA, and it corresponds to 875 V between 1 m distant. The amount of charge flowing a passenger at 100 kA impulse current can be estimated to $0.31\;mA{\cdot}s$. This is much less than the limit amount of charge for human body, $30\;mA{\cdot}s$ which is presented by Koeppen and Osypka.

• 보건교육건강증진학회지
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• 제23권2호
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• pp.1-10
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• 2006

Purpose: This study was aimed to evaluate the effects of substance abuse prevention education for middle school students in Busan. Method: The data were collected by a self-administered questionnaire before education and one month later. The whole subjects were 458 students in first grade of middle school. The data were analyzed using frequencies and difference t-test after classifying the whole into potential drug abuse group and not potential group. Results: The substance abuse prevention education was ineffective in the whole group and the potential group. However, in the not potential group, the increasing rate of SPDA(Screening scale for Potential Drug-use Adolescents) score in experimental group was less than in control group. Conclusion: The substance abuse prevention education was effective for the not potential drug abuse group. On the other hand, intensive long-term drug abuse treatment program was needed for the potential group.