• 대한의용생체공학회:의공학회지
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• 제26권1호
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• pp.49-54
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• 2005

This paper presents a design of 1-channel active dry electrode module for EEG from one's forehead. The IA(instrumentation amplifier) circuit inside the module is based on the configuration sown on the paper MettingVanRijn et al. We analyze the IA circuit to find out the related equation, and then compare its simulated characteristic with the result obtained from the real active dry electrode circuit. With the active dry electrode and the wet(Ag/AgCI) electrode connected to the separated analog processing module on one's forehead at the same time, their real time and FFT outputs of EEG are examined for comparison. The active dry electrode module has advantages over the wet electrode and its analog processing module: 1) The size of the analog processing circuit of the active dry electrode module is smaller than that of existing EEG analog processing module; 2) the total cost required to make the proposed analog processing circuit is much lower than that of the existing circuit, since the designed circuit needs smaller parts; 3) the electrical characteristic is comparable to the general EEG analog processing module even if the designed module has simpler circuit configuration.

• 설비공학논문집
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• 제15권6호
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• pp.489-494
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• 2003

"Anmadang" of traditional Korean house is an empty space, surrounded by buildings shaped like the letter, ‘ㅁ’.‘ㅁ’shaped traditional Korean house provides much more comfortable outdoor space for various activities than ‘ㅡ’shaped traditional Korean house. In this paper it has been tried to analyse the dry bulb temperature condition of indoor and outdoor space through measurement of dry bulb temperature in Anmadang, Maru and outdoor space. This paper also analyses the correlation of dry bulb temperature between Anmadang and outdoor space with seasonal variations in traditional Korean houses.

• 펄프종이기술
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• 제35권3호
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• pp.29-36
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• 2003

Reducing the energy consumption while maintaining pulp quality is an important objective of today's paper industry. Enzymatic treatment of fibers and the application of dry strength agent were investigated as methods to reduce energy consumption during refining and to upgrade fiber characteristics. Modification of recycled fibers with an enzyme was effective in improving relining efficiency and reducing refining energy. Optimization of dry strength agent application conditions including stock pH, cationic demand, zeta potential, etc. were found to be very important for improving its effectiveness.

• 한국안광학회지
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• 제18권2호
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• pp.93-99
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• 2013

목적: 본 연구는 현장현시 건성안 진단 테스트 중에 현재 사용되고 있으나 부정확한 결과로 신뢰도가 떨어지는 쉬르머 용지를 대체 할 수 있는 차세대 건성안 진단 테스트 용지를 미세유체공학을 이용하여 개발하고자 하였다. 방법: 왁스로 패턴을 제조한 친수성 크로마토그래피 용지를 pH에 따른 색 변화가 나타나도록 안토시안으로 염색을 하였다. 인공 누액의 젖음 속도를 인공 누액과 32명의 참가자의 눈물을 이용하여 임상 측정하였다. 결과: 인공 누액을 이용하였을 경우 쉬르머 용지에서는 소량의 용액은(0.5 ml이하) 흡수거리가 도출되지 않았으나 새로 개발된 용지는 시간에 따른 인공 누액의 흡수거리가 확연히 나타났다. 임상실험에서도 새로 개발된 검사 용지는 TBUT (tear break-up time)결과와 부합하는 건성안 진단 결과를 보였다. 결론: 개발된 건성안 진단 용지는 간편하게 사용될 수 있을 뿐만 아니라 기존 쉬르머 용지와 같은 현장현시 건성안 진단 매체와 비교 했을 경우 건성안 판별의 정확성이 높았다.

• 한국농공학회지
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• 제37권E호
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• pp.72-78
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• 1995

To support some knowledge in planning irrigation system, short or long-term irrigation scheduling or determining irrigation reservoir capacity, it is necessary to estimate peak irrigation requirements and seasonal distribution of water demands for various return periods. In this paper Dry Day Index and Probable Evapotranspiration were evaluated to decide seasonal consumptive use of paddy rice for a design year using several decades' daily rainfall data and 5 years'('82~'86) actual evapotranspiration data, respectively. To obtain Dry Day Index that is defined as the number of probable dry days for a given period, Slade unsymmetrical distribution function was adopted. Dry Day Index was analysed for 5 and 10-day intervals. Each of them was evaluated with return periods of 1, 3, 5, 10 and 20 year. Their singnificance was tested by X$^2$ method. Based on these values, the Probable Evaportanspiration, that is the average daily ET both in dry days and rainy days during a given period, was estimated. Crop coefficient was also determined by the modified Penman equation proposed by Doorenbos & Pruitt.

• 대한환경공학회지
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• 제32권9호
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• pp.870-878
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• 2010

본 연구는 산업 현장에서 나오는 폐지, 폐목재에 함유되어 있는 17종 PCDD/Fs, 12종 Co-PCBs, 16종 PAHs 농도 수준과 이들의 발생원 추적을 위해 수행되었다. 농도 수준은 폐지와 폐목재 순으로 PCDD/Fs는 9.69~176.77 pg/g-dry, 0.14~0.25 pg/g-dry, Co-PCBs는 109.95~4097.25 pg/g-dry, 28.23~59.88 pg/g-dry, PAHs는 9.30~52.18 ng/g-dry, 0.82~1.82 ng/g-dry로 조사되었으며, 모든 대상물질은 폐목재보다 폐지에서 더 높은 농도로 검출되었다. PCDD/Fs 중 OCDD가 가장 높은 농도로 검출되었으며, 소각로 배출가스 중 다이옥신과 유사한 패턴을 보였다. Co-PCBs 이성질체 분포 패턴은 상용 PCB 제품의 이성질체 분포패턴과 유사하게 나타나 이로 인한 오염으로 판단되었고, PAHs의 경우 특정 화합물의 농도비를 이용하여 추정한 결과 폐기물 소각과 같은 연소와 관련이 있음을 알 수 있었다.

• 전기학회논문지
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• 제57권10호
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• pp.1731-1737
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• 2008

This paper present the fundamental insulation characteristics of Dry Air gas and insulation coating in high voltage power apparatus. It is known that the dielectric strength. of Dry Air is approximately one-third that of SF6 gas. we attempt that the insulation coating and dry air gas have replaced the SF6 gas as insulation of the switchgear. We proposed the dry air insulated switchgear(DAIS) for High Voltage apparatus. To acquire technology of insulation characteristic improvement made standards for complex insulation structure and conducted simulations and experiments

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2003년도 추계학술대회
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• pp.66-70
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• 2003

Recently, environmental conscious machining becomes one of the most important technology in modern manufacturing industry. Especially in metal cutting, cutting fluid often results in many environmental problems. Many technologies have been developed to reduce the problems of the cutting fluid. But most of the technologies need another devices which sometimes require large space and also are very expensive, such as cooling system. In this paper, air compressor is only used to replace the functions of cutting fluid as semi-dry cutting. Cutting forces, cutting moments, and tool wear were measured to obtain cutting characteristics, and were compared with those of dry cutting and non-dry cutting. In the results of the experiments, semi-dry cutting was found to show better cutting performances than dry cutting and non-dry cutting.

• 한국해양학회지
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• 제12권1호
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• pp.41-47
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• 1977

The present paper deals with nine kinds of trace metal contents among 79 samples, more than 20 species of edible marine algae collected during 1973∼1975 along the coasts of Korea. Among the metals detected by the atomic absorption spectrometer, Mg content is variable in 2.09∼13.84mg/g-dry on an average and 5.31mg/g-dry in a mean of green, brown and red algae, whereas Fe is 0.148∼2.343 and 0.747mg/g-dry; Mn 0.015∼0.191 and 0.063mg/g-dry; Zn 0.007∼0.082 and 0.030 mg/g-dry; Cu 0.005∼0.054 and 0.017mg/g-dry; Pb 0.0017∼0.082 and 0.0043mg/g-dry Co 0.0009∼0.0024 and 0.0016mg/g-dry; Cd 0.0002∼0.0034 and 0.0011mg/g-dry, and Cr is 0.0007∼0.0074 and 0.0021mg/g-dry, both on an average and in a mean respectively. The trace metal contents in the seaweeds investigated are variable according to species, collecting seasons, places and kinds of metal It is interesting that in Sargassum thunbergii some metal contents such as Fe, Mn, and Zn are specially high in September1974 through the year investigated.

• Journal of international Conference on Electrical Machines and Systems
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• 제3권2호
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• pp.200-206
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• 2014

This paper describes magnetically levitated vehicle with hybrid magnets, which have been studied by the authors in place of streetcars or conveyance system. An experimental vehicle of 20kg was magnetically levitated by using a small number of dry-cell batteries, which consisted of 10 Ni-MH cells of 1900mAh in series. The magnets were activated sequentially, because the internal resistance of the batteries suppressed the maximum current. The vehicle was kept levitating for about 2 hours and was stable against disturbance due to instantaneous external force. In this paper, dynamic characteristics of the magnetically levitated vehicle using a small number of dry cell batteries are presented.