• 한국전산유체공학회:학술대회논문집
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• 2008.03a
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• pp.227-228
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• 2008

In the present paper, fowler flap was optimized to maximize the lift with response surface method. Leading edge shape and the gap between main airfoil and flap, were optimized and the aerodynamic characteristics was improved considerably. The optimized flap has more rounded leading edge and bigger gap. Before angle of attack, $10^{\circ}$, lift and drag are improved and the optimized flap shows similar aerodynamic characteristics to the original flap. The flow condition for optimization was angle of attack, $10^{\circ}$, Mach number, 0.2, flap deflection, $40^{\circ}$.

• 한국전산유체공학회:학술대회논문집
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• 2008.10a
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• pp.227-228
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• 2008

In the present paper, fowler flap was optimized to maximize the lift with response surface method. Leading edge shape and the gap between main airfoil and flap, were optimized and the aerodynamic characteristics was improved considerably. The optimized flap has more rounded leading edge and bigger gap. Before angle of attack, $10^{\circ}$, lift and drag are improved and the optimized flap shows similar aerodynamic characteristics to the original flap. The flow condition for optimization was angle of attack, $10^{\circ}$, Mach number, 0.2, flap deflection, $40^{\circ}$.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2002.05a
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• pp.181-186
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• 2002

Fouling causes serious maintenance problems on heat exchanger tubes and process facilities. To avoid such fouling problems, numerous efforts have been tried, e.g., diagnosis of fouling, reducing and eliminating the fouling, etc.. The objective of the present study is to develop an innovative diagnostic system of fouling, which can detect the scaling attached to the wall non-homogeneously The performance of the diagnostic system has been evaluated with a scaling simulator that generates scaling on tested tube wall The measured values with the diagnostic system were compared with the amounts of the scaling generated by the simulator.

• Proceedings of the KSME Conference
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• 2000.04b
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• pp.180-186
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• 2000

This paper presents a new winding method in the electronic descaling(ED) technology. The ED technology Produces an oscillating electric field via the Faraday's law to Provide necessary molecular agitation to dissolved mineral ions. But present method gives another agitation force to mineral ions, which is Lorentz's force. Experiments were peformed at various Renolds number. A series of tests was conducted, measuring pressure drop across test section and the overall heat transfer coefficient as a function of time. In order to accelerate the rate of fouling, artificial hard water of 1000ppm $CaCO_3$ was used throughout the tests. The results show that the new method accelerates collision of mineral ions and improvs efficiency of system.

• Proceedings of the Korean Information Science Society Conference
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• 2001.10b
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• pp.277-279
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• 2001

최근 디지털 비디오 데이터의 사용이 급격히 증가하면서 저급 수준의 정보를 이용하여 고급 수준의 내용 정보를 자동으로 추출하는 기술이 필요하게 되었다. 축구와 같은 분야에서는 그 중에서도 골, 프리킥, 파울 장면 등의 고급 수준 내용 정보가 중요한 의미를 갖게 되는데 특히, 이러한 장면 중 중요하다고 여기는 장면은 재연 장면을 통하여 다시 시청자에게 보여주게 되며, 축구 비디오에 대한 요약에서는 이런 장면들이 꼭 포함되어야 한다. 본 논문에서는 이러한 축구 비디오 데이터에서 재연 장면을 자동으로 추출하는 방법을 제안한다. 기본적으로는 축구 고유의 특징들을 이용하는데 첫 번째 특징은 샷의 길이가 너무 짧거나 너무 길지 않다는 것이고, 두 번째 특징은 재연 장면이라는 것은 장면이 느리게 다시 재생되는 것이기 때문에 움직임 특징이 일반적인 장면과는 다르다는 것이다. 본 논문에서는 오브젝트의 움직임을 구분하기 위하여 재연 장면을 두 가지 종류로 나누었다. 하나는 확대 상태의 재연 장면이고 다른 하나는 축소 상태의 재연 장면이다. 본 논문의 알고리즘을 적용하여 실험한 결과 Recall과 precision 모두 77% 이상 나오는 것을 알 수 있었다.

• 한국연소학회:학술대회논문집
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• 2013.06a
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• pp.65-68
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• 2013

In a syngas cooling system of coal gasification process, fly slag carried by syngas deposit on the surface of heat exchanger. The deposited materials form a fouling layer with several millimeters thickness, disturbing heat transfer between steam and syngas. This study investigates flow and heat transfer characteristics of syngas in helical coil heat exchanger using computational fluid dynamics under clean and fouled surface condition. Process model were also designed and its results are in good agreement with CFD results.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2019.05a
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• pp.236-237
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• 2019

IMO는 MEPC 73차(2018.10) 회의에서 선박부착생물 관리절차, 방오성능, 수중소제, 선체설계 및 교육사항이 구체적으로 명시될 수 있도록 기존 지침의 유효성평가가 승인되었으며 수집된 정보를 바탕으로 관리지침서 개정을 검토하고 있어 향후 선박부착생물 관리 가이드라인도 규제화 될 가능성이 높다. 우리나라는 IMO 선체 부착생물규제 대응하기 위해 외래 유해침임종 관리를 위한 최적을 방안을 도출 할 필요가 있다.

• Proceedings of the Korea Information Processing Society Conference
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• 2023.05a
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• pp.165-167
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• 2023

양자 컴퓨터는 기존의 클래식 컴퓨터와 달리 양자역학 원리를 활용해 정보 처리를 수행하며, 특정 문제들을 훨씬 빠르게 해결할 수 있다. 양자 컴퓨터는 큐빗을 기본 단위로 사용하고, 아다마르 게이트, CNOT 게이트, 파울리 게이트, 토플리 게이트 등을 조합하여 양자 회로를 구성한다. Toffoli 게이트는 유니버설 게이트 중 하나로, 세 개의 큐빗을 입력받아 조건부 (Controlled-Controlled) NOT 연산을 수행한다. 이 게이트는 복잡한 작업을 기본 양자 게이트로 분해할 수 있어, 회로의 게이트 수, 깊이 및 오류율 측면에서 최적화할 수 있다. 기본 양자 게이트 중 T 게이트는 노이즈와 오류에 영향을 받을 수 있으므로, T 게이트의 수와 깊이를 최적화하는 것이 중요하다. 본 논문은 Toffoli 게이트 분해를 통해 양자 회로의 게이트 수와 깊이를 최적화하는 방법을 조사한다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.11
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• pp.224-231
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• 2019

Recently, the pollution of groundwater has become serious. In particular, the contamination of groundwater near livestock farms is becoming increasingly severe and it is difficult to drink with drinking water. In this paper, a groundwater purifier apparatus that can be installed in a community well was designed. The designed groundwater purifier apparatus enables a RO membrane filter and UV sterilization to remove pollutants, such as heavy metals, bacteria, and organic compounds. In addition, electrical conductivity, pressure, and flow sensors were added for remote monitoring. Remote monitoring of the system can determine the level of fouling and contamination of RO membrane filters through pressure and flow sensor data, and can record changes in the contamination and condition of groundwater through the electrical conductivity of the feed water. The designed groundwater purifier apparatus was installed at a farmhouse and remote monitoring. The result after 15 days of operating a groundwater purifier apparatus and analyzing the monitoring data revealed an average permeate water flow rate of 2.67L/min and an average water pressure of 7.09kgf/㎠, indicating that the RO Membrane filtered without fouling and clogging. The average electrical conductivity was 796.6 S/㎠ of the feed water and 55.6 S/㎠ of permeate water, which is similar to that of general tap water. Through this, it was confirmed that no pollutant occurred in the surroundings. Therefore, the designed groundwater purifier apparatus can confirm the replacement time of the RO membrane filter in advance through remote monitoring, and check the pollution state of the groundwater.

• Journal of Korean Library and Information Science Society
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• v.46 no.3
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• pp.301-323
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• 2015

This study was conducted to analyze the characteristics of records related to Korea shown in the cataloging records of major 10 Asia-Pacific university libraries. The results are as follows. To begin with, Korea-related records in most university libraries are very poor except for some libraries and are generally 2 times less than Japan related records. There are even 6 times less in 2 libraries. Second, most libraries organize records in MARC 21 format rather than UNIMARC, and apply subject headings of the national library, or go together with LCSH. Third, Korean materials usually write Korean in Roman characters, but 5 libraries are marked with the original Korean language and available Hangeul search. Forth, on investigation of the subject distribution in sub criteria of Korea-related records, subject related to 'history', 'economy', and 'politics' is largely shown in the highest rate. Fifth, Among the Korea-related subject heading, the terms such as 'Taekwondo', 'Kimchi', 'Dokdo', 'Donghae', 'Duman-gang', 'Baekdu-san' have different meanings in different libraries. However, these terms agree to LCSH in most libraries except for neighboring countries's libraries.