• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2007년도 춘계종합학술대회
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• pp.540-543
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• 2007

본 논문에서는 모바일 TFT-LCD 모듈에서 발생하는 가청잡음을 감소시키기 위한 새로운 방법을 제안한다. 또한 가청잡음에 영향을 미치는 중요 인자들을 분석하였다. 이러한 잡음원은 FPCB와 LCD 패널간의 진동 및 윈도우와 백라이트에 충전되어 있던 정전기와 같은 다양한 중요 인자들로부터 유래됨을 확인하였다. 윈도우에 충전되어 있던 정전기로 인한 잡음 수준을 분석하기 위해 윈도우가 없는 LCD 모듈과 윈도우가 있는 LCD 모듈이 동시에 평가되었다. 신뢰감이 있고 재현성이 있는 데이터를 확보하기 위해 테스트 지그 및 측정시스템을 구축하였다.

• 한국환경보건학회지
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• 제37권1호
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• pp.57-63
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• 2011

Crocidolite quality control (QC) sampling created by the wet generation method has been validated by validation tests such as the accuracy, precision, and storage tests. For this study we designed and developed a manufacturing apparatus and standard operating procedure for making these QC samples. The most important step in the procedure of making QC samples was the stage eliminating static electricity in asbestos fibers. This static electricity hampers the fibers clog functioning. In accuracy and precision tests by phase contrast microscopy analysis, the difference between the reference values and the studied values was at maximum 17.8%. This satisfies the AIHA proficiency analytical test criteria for asbestos. We could confirm the nearly even distribution of crocidolite fibers on the membrane filter. Also, there was no loss of fibers in the storage test after the one month.

• 센서학회지
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• 제7권2호
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• pp.140-146
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• 1998

정전기는 고집적 반도체소자의 제조공정에서 제품의 제조수율을 감소시키거나, 정전하에 의해 가스폭발이나 화재 등을 일으키는 원인이 되므로 정전기를 제거하기 위한 수단이나 장치가 필수적으로 요구된다. 본 논문에서는 전하중화장치의 사용시간 경과에 따른 침전극 마모 및 분진부착 특성에 대해서 실험적으로 연구하였다. 또한 전하중화장치의 침전극의 마모 최소화와 발생이온량의 정량적인 제어를 위해 인가전원을 종래의 교류전원 대신에 고주파 펄스전원으로 하여 펄스주파수 및 펄스의 시비율을 변화시킴으로서, 펄스전력을 유효하게 제어할 수 있었으며, 또 펄스전원을 사용함으로서 전하중화장치의 이온 발생특성을 크게 할 수 있음을 실험적으로 확인하였다.

• 한국안전학회지
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• 제34권4호
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• pp.22-31
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• 2019

The flammable liquid conductivity is an important factor in determining the generation of electrostatic in fire and explosion hazardous areas, so it is necessary to study the physical properties of flammable liquids. In particular, the relevant liquid conductivity in the process of handling flammable liquids in relation to the risk assessment and risk control in fire and explosion hazard areas, such as chemical plants, is classified as a main evaluation item according to the IEC standard, and it is necessary to have flammable liquid conductivity measuring devices and related data are required depending on the handling conditions of the material, such as temperature and mixing ratio for preventing the fire and explosion related to electrostatic. In addition, IEC 60079-32-2 [Explosive Atmospheres-Part 32-2 (Electrostatic hazards-Tests)] refers to the measuring device standard and the conductivity of a single substance. It was concluded that there is no measurement data according to the handling conditions such as mixing ratio of flammable liquid and temperature together with the use and measurement examples. We have developed the measurement reliability by improving the structure, material and measurement method of measuring device by referring to the IEC standard. We have developed a measurement device that is developed and manufactured by itself. The test results of flammable liquid conductivity measurement and the data of the NFPA 77 (Recommended Practice on Static Electricity) Annex B Table B.2 Static Electric Characteristic of Liquids were compared and verified by conducting the conductivity measurement of the flammable liquid handled in the fire and explosion hazardous place by using Measuring / Data Acquisition / Processing / PC Communication. It will contribute to the prevention of static electricity related disaster by taking preliminary measures for fire and explosion prevention by providing technical guidance for static electricity risk assessment and risk control through flammable liquid conductivity measurement experiment. In addition, based on the experimental results, it is possible to create a big data base by constructing electrostatic physical characteristic data of flammable liquids by process and material. Also, it is analyzed that it will contribute to the foundation composition for adding the specific information of conductivity of flammable liquid to the physical and chemical characteristics of MSDS.

• 한국산업융합학회 논문집
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• 제21권4호
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• pp.149-158
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• 2018

With the propagation and spread of the new regeneration energy and increase in electricity demand, power systems tend to be decentralized, and accordingly, the use of a power system stabilizer tends to expand for the stabilization of the distribution system. Thus, typical power system stabilizer, Static Var Compensator (SVC) is developed on a variety of topologies. In addition, the trend of technology leads from SVC to Static Synchronous Compensator(STATCOM) technology development. Recently, to overcome STATCOM's conversion losses and economic disadvantages, studies of a hybrid method using STATCOM and SVC in parallel have actively been conducted. This study proposes a new Soft-Step Switching method to limit inrush current problematic in Thyristor Controlled Capacitor (TCC) method in SVC function. In addition, to reduce Statcom's capacity, groups of reactive power compensation reactor and condenser for SVC were designed.

• Journal of Electrical Engineering and Technology
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• 제6권1호
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• pp.14-24
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• 2011

In order to facilitate the electricity market operation and trade in the restructured environment, ample transmission capability should be provided to satisfy the demand of increasing power transactions. The conflict of this requirement and the restrictions on the transmission expansion in the restructured electricity market has motivated the development of methodologies to enhance the available transfer capability (ATC) of existing transmission grids. The insertion of flexible AC transmission System (FACTS) devices in electrical systems seems to be a promising strategy to enhance single area ATC and multi-area ATC. In this paper, the viability and technical merits of boosting single area ATC and multi-area ATC using Thyristor controlled series compensator (TCSC), static VAR compensator (SVC) and unified power flow controller (UPFC) in single device and multi-type three similar and different device combinations are analyzed. Particle swarm optimization (PSO) algorithm is employed to obtain the optimal settings of FACTS devices. The installation cost is also calculated. The study has been carried out on IEEE 30 bus and IEEE 118 bus systems for the selected bilateral, multilateral and area wise transactions.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 학술대회 논문집 전문대학교육위원
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• pp.83-87
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• 2007

Correlation Propagation Neural Networks is proposed for On-line interpolation. The proposed neural network technique is the real time computation method through the inter-node diffusion. In the network, a node corresponds to a state in the quantized input space. Each node is composed of a processing unit and fixed weights from its neighbor nodes as well as its input terminal. Information propagates among neighbor nodes laterally and inter-node interpolation is achieved. Through several simulation experiments, real time reconstruction of the nonlinear image information is processed. 1-D CPNN hardware has been implemented with general purpose analog ICs to test the interpolation capability of the proposed neural networks. Experiments with static and dynamic signals have been done upon the CPNN hardware.

• Journal of Power Electronics
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• 제11권1호
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• pp.90-96
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• 2011

Congestion management is one of the most challenging aspects in the recently deregulated electricity markets. FACTS devices have been shown to be an efficient alternative to control the flow of power in lines, resulting in increased loadability, lower system loss and a reduced cost of production. In this paper, the application of a static series synchronous compensator (SSSC) for the purpose of congestion management of power systems has been studied. A sensitivity-based analysis method is utilized for effective determination of the SSSC location in an electricity market. The method is topology based and it is independent of the system operation point. A power injection p-model is developed for the SSSC in this study. Numerical results based on the modified IEEE 14 bus system with/without the SSSC demonstrate the feasibility as well as the effectiveness of the SSSC for congestion management in a network. The results obtained when using the SSSC to improve system transfer capability and congestion management is encouraging.

• 한국안전학회지
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• 제35권1호
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• pp.1-11
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• 2020

Article 325 (Prevention of Fire Explosion due to Electrostatic) of the Rule for Occupational Safety and Health Standard specifies that in order to prevent the risk of disasters caused by static electricity, fire, explosion and static electricity in the production process, However, in order to do this, it is absolutely necessary to use a pre-detection technology and a detector for antistatic discharge prediction, which is a precautionary measure by static electricity in a fire / explosion hazard place, but in Korea, And there is no technical standard for the application of the technology of the explosion proof structure of the related equipment. Research methods include domestic and overseas electrostatic discharge detection technology and literature investigation of related equipment explosion proofing technology, domestic and foreign electrostatic discharge detection device production and use situation investigation, advanced foreign technology data analysis and benchmarking. In particular, we sought to verify the results of empirical experiments using electrostatic discharge detection technology through sample purchase and analysis of related major products, development of optimization technology through prototype production, evaluation, and supplementation, and expert knowledge through expert consultation. The results of this study were developed and fabricated two prototypes of electrostatic discharge detector based on the technology / standard related to electrostatic discharge detection technology in Korea and abroad through development of electrostatic discharge detection technology and development and production of detector. In addition, based on the development of electrostatic discharge detection technology, we developed an intrinsic safety explosion proof ib class explosion proof technology applicable to the process of using and handling flammable gas and flammable liquid vapor and combustible dust. In the case of the over voltage and minimum voltage are supplied to the explosion-proof structure ESD detector, check the state of the circuit and the transient and transient currents generated by the coil and capacitor elements during the input and standby of the signal pulse voltage. Explosion-proof equipment-Part 11: Intrinsically safe explosion proof structure The comparative evaluation with the reference curve in Annex A of "i" confirms that the characteristics of the intrinsically safe explosion protection structure are met.

• Fibers and Polymers
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• 제5권2호
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• pp.151-155
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• 2004

Cold plasma of $O_2$ or Ar was irradiated on hydrophobic Kapton surface to attenuate or remove the electrostatic potential. A measurement on charge dissipation speed clarifies the obscure effect of plasma. These consequences reveal that $O_2$ plasma etching is more effective than Ar plasma. After 30 days, the dissipation speed of accumulated charge on initially etched sample has not changed under summer season.