• Proceedings of the Korean Vacuum Society Conference
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.122-122
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• 2014

수중방전을 환경분야에 적용하기 위한 플라즈마 부상법이 개발되었다. 플라즈마 부상법은 물 속에서 발생시킨 플라즈마가 가지고 있는 주요특성 중 물리적 특징인 쇼크웨이브, UV조사, 버블생성 등과 화학적 특징인 OH라디칼 및 염소산화물 생성 등을 이용하여 물 속에 존재하는 용존성 및 입자성 물질을 부상분리 기법으로 제거하는 공법이다. 유기물을 제거하는 기작으로는 침전, 여과, 분해 등이 있고, 이를 구현하기 위한 공정으로 중력침강법, 부상분리법, 멤브레인법, 미생물법 등이 있다. 이 중에서 가압공기부상법은 침강법에 비해 부지면적을 적게 소모하고 처리시간이 50% 이상 감소되는 특징이 있다. 가압공기부상법은 물 속에 공기를 과포화시킨 후 노즐을 통해 재분사할 때 발생하는 압력차에 의해 미세기포가 발생함을 이용하여 유기물을 분리하는 공법이다. 그러나, 가압용 장비 및 반송수가 필요하고, 미생물분리는 불가능한 단점이 있다. 이에 본 연구에서는 미생물살균과 유기물 분리가 동시에 일어나는 플라즈마를 이용한 부상분리기법을 개발하였다. 본 연구에서는 난분해성 용존유기물인 휴믹산 100 mg/L의 플라즈마 공기부상법에 의한 제거능을 확인하였다. 용존성 휴믹산을 입자성 물질로 전환하여 플록을 형성시키고자 알루미늄설페이트(Al2(SO4) $3{\cdot}18H2O$)를 100 mg/L 주입하였고, 침출수와 같이 염도가 높은 물을 모사하고자 35 g/L의 염화나트륨을 첨가한 상태에서 방전을 실시하였다. 방전에 사용된 전원은 EESYS사에서 제작한 펄스형 고전압 전원장치를 사용하였고 최대 15 kW의 출력 중 6 kW의 전력을 인가하였다. 전극 한 개는 2 mm 텅스텐봉을 세라믹튜브로 감싼 구조로 총 사용전극은 28개이다. 전극 한 개당 대략 200 Watt의 전력이 소모되며 이 때 최대의 버블이 생성됨을 확인하였다. 전극 1개에서 생성되는 버블의 부피는 14 mL/min 로 측정되었다. 버블의 크기는 평균 70 um이고 가압공기부상법에서 최적공기크기로 제시하고 있는 40~80 um 의 버블은 약 80% 가량 생성된다. 본 연구에서 사용된 반응시스템에서의 물의 높이는 약 500 mm 이고 전체 40 L의 수조가 3개의 벽으로 분리되어 4개의 수조로 분리되었다. 각 수조는 하부에 7개의 전극을 포함하고 있다. 플라즈마 발생시 생성되는 기포는 약 1분 방전 후에 포화농도에 도달하며 방전종료 후 약 4분간 수체 내에 남아있게 된다. 이를 공정에 적용하여 1분 방전 및 4분 휴지의 순서로 플라즈마를 인가하였다. 휴믹산 용액의 유량을 2 lpm 으로 운전하였을 때 최종 처리율은 94% 이고 이때의 대장균 살균능은 99%이다.

• Applied Biological Chemistry
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• 제14권1호
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• pp.19-27
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• 1971

This experiment was conducted as a preliminary test to invent the quick ripening process for soysauces. The bran koji extract of 2 kinds of mold (Asp. niger and Asp. sojae) was used as enzyme sources in order to improve the rate of enzymatic conversion of raw materials and shorten the ripening period of soysauces. Soybean koji (inoculated Asp. sojae) and steamed soybean were enzymatically decomposed for 8 hours at $40^{\circ}C$, pH 4-6 with stirring at a rate of 1500 rpm. After the enzymatic treatment, soysauces were fermented by 4 kinds of processes with the above-mentioned salt tolerant microorganisms inoculated. After 4 weeks, sensory evolution for these soysauces products and analysis of chemical components were carried out. The results obtained were summarized as follows. 1. Soysauces prepared from decomposed koji by Asp. niger enzyme complex showed higher extractables, such as total nitrogen, amino nitrogen, pure extract and reducing sugar, than any other procedure. Extracted amounts of each components of soysauces prepared from this process during 1 month were similar to those of soysauces made from general procedure (control) for 5 to 6 months. 2. According to sensory evaluation, soysauce prepared from decomposed koji also showed best taste and were similar to that of soysauces prepared by general method for 6 months.

• Korean Journal of Food Science and Technology
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• 제32권3호
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• pp.634-639
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• 2000

This study was done to determine the changes in physicochemical components focused on the general compositions, pH, titratable acidity, organic acids, color and sugars during the microwave roasting of cocoa mass and to compare the changes with those during a conventional roasting. The cocoa mass was microwave-roasted at 110 to $150^{circ}C$ and for 10 to 40 min or conventionally roasted at $140^{circ}C$ for 30 min. General compositions of microwave-roasted cocoa mass were not different from those of raw cocoa mass or conventionally-roasted one. The pH changes did not affect the changes in titratable acidity or organic acids. Titratable acidity was different among the three samples. Microwave-roasted cocoa mass showed less sufficient effects on removing organic acids and less changes in color. Fructose, glucose and maltose decreased during a roasting but sucrose showed little changes.

• Journal of Legislation Research
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• 제53호
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• pp.491-524
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• 2017

Under the general maritime law, a life salvor has no claim against the person saved, and a pure life salvor has no right to compensation from the owner of the ship or its cargo. This harsh rule, which treats the salvor of life less generously than the salvor of property, has been modified by international conventions, statutes, so that life salvors may expect a reward in most cases. It is, especially, unreasonable that a prerequisite of a salvage award is that at least some of the property must be saved, because life of a person can not be compared to values of goods such as vessels and cargoes. Also it is not understandable that only pure life salvors can not expect a reward for the saving of life from the owners of the property. In the meantime, according to Article 39 of the Korean Maritime Search and Rescue Act (hereunder, KMSARA), any person who has gave assistance and rescued in accordance with a governmental officer's order may get a compensation for their time and labour. The above mentioned compensation which is stemmed from the KMSARA may play a role as a compliment for the lack of enough compensation to a life salvor. This means that even though a life salvor failed to save property, he may expect a minimum compensation from the KMSARA. However, it should be recognized that when a life salvor is entitled to both remuneration for the salvage of life and recourse of expenditures from the KMSARA, the total remuneration shall be paid only if and to the extent that such remuneration is greater than any reward recoverable by the salvor under the Korean Commercial Code and the KMSARA.

• Proceedings of the Materials Research Society of Korea Conference
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• 한국재료학회 2002년도 춘계 학술발표강연 및 논문개요집
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• pp.57-57
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• 2002

• Aerospace Industry
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• 제69권
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• pp.12-14
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• 1999

지난 10월 1일 한국항공우주산업(주)는 발기인 총회를 개최하고 상법상의 주식회사로 정식 설립되기 위한 준비에 들어갔다. 이로써 항공우주산업(주)는 자금, 시설, 인력의 효율적인 운영과 훈련기, 경전투기, 헬기 등을 자체 생산하여 2010년까지 우리나라가 세계 10위권 항공산업국으로 발돋움 하는데 큰 역할을 할 것으로 기대된다.

• YAKHAK HOEJI
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• 제7권4호
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• pp.92-95
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• 1963

Magnesium Chlorophyllin 으로부터 상법에 의하여 제조한 Chlorin-e에 수용성 Cobalt 염을 작용시켜 Chlorophyllin에 Cobalt Complex 화합물을 제조하였다. Chlorin제법에 있어서 alcohol 용매를 사용해 온 방법은 Chlorin이 alcohol에 대한 용해도가 그히 적은 관계로 목적물을 양호한 수대율로 얻지 못할 뿐만 아니라 이에 따르는 조작도 복잡 불편하였으나 용매 를 빙초산으로 대치하므로써 좋은 성과를 얻을 수가 있었다.

• Proceedings of the KSME Conference
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.3418-3422
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• 2007

The neutron imaging technique was used to investigate the water discharge characteristics at PEMFC. Prior to investigation of water discharge characteristics, the linear attenuation coefficient for water at Neutron Radiography Facility (NRF) was calibrated. The feasibility test apparatus was consisted of pressurized air and water in order to simulate the actual operating PEMFC. The feasibility tests have been performed at 1-parallel serpentine type with 100 $cm^2$ active area and different air flow rate (1, 2, and 4 lpm). The total water volume variations at each condition were calculated from the neutron images. The water at channel is well discharged as soon as supplying the pressurized air into the PEMFC. However, because the water at MEA isn't removed the total water volume is constant after 150. Therefore more effective method is needed in order to discharge water at MEA, and the neutron imaging technique is helpful for it.

• Korean Journal of Crystallography
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• 제4권1호
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• pp.11-17
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• 1993

Corundum single crystals were grown by the Czochralski technique. Relationships between crystal quality and crystal growth factors such as pulling rate, rotation rate and temperature of the melt were investigated. Optimum pulling and rotation rate for high quality corundum single crystal growth were 4.0mm/hr, 30rpm respectively. Pore was a main defect in corundum crystal and also discussed how to remove this defect by melt temperature control. Growth direction of as grown crystals was identified with(0001). And this direction had largest growth rate. Room temperature absorption spectra were measured and discussed for Cr3+ion doped and non-doped corundum crystals.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• 제16권3호
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• pp.335-343
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• 2005

In this paper, we propose a method to classify inverse synthetic aperture radar(ISAR) image from different target. The approach can provide efficient features for classification by the combined use of a polar mapping procedure and a well-designed classifier The resulting feature vectors are able to meet requirements that efficient features should have : invariance with respect to rotation and scale, small dimensionality, as well as highly discriminative information. Typical experimental examples of the proposed method are provided and discussed.