• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.675-678
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• 2003

Experimental results for variation of concrete strength according to vibration time control for fresh concrete were given. Vibration velocity, time before vibration and vibrating time were used as experimental parameters. Compressive strength, split tensile strength, ana bond strength were investigated and then fracture surfaces of split tensile strength specimen were observed. From the experimental results, it could be concluded that there may be no decrease in concrete strengths if time before vibration will be sustained at least for more than 3 hours.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.281-282
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• 2003

Olfactometer를 이용한 악취평가방법은 1986년 미국에서 표준방법(ASTM)으로 인정된 후 유럽 공동체(prEN 13725), 독일(VDI), 네덜란드(NVN2820) 등 여러나라에서 표준방법으로 다양하게 활용되고 있다. Olfactometer의 개발은 초기에 가축사육시설 부근의 냄새 유발에 따른 냄새의 정량화와 냄새 제어를 목적으로 발전하였으나, 근래에는 공업화와 산업화에 따른 산단지역에서의 냄새 배출원평가와 관리 및 부지경계에서의 냄새 농도평가의 필요성에 따라 많은 개발과 발전을 이루어왔다. (중략)

• Review of KIISC
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• v.30 no.1
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• pp.43-53
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• 2020

딥러닝 기술의 발달로 인해 다양한 응용 분야에서 해당 기술 활용 시 좋은 성능을 보임에 따라 부채널 분석 분야에서도 딥러닝 기술을 적용하는 연구들이 활발히 진행되고 있다. 초기 딥러닝 기술은 데이터 분류 문제를 해결해야 하는 템플릿 공격과 같은 프로파일링 기반의 부채널 공격에 집중되어 적용되었지만 최근에는 프로파일링 기반의 부채널 분석 뿐만 아니라 상관 전력 분석 등과 같은 논프로파일링 기반 부채널 공격, 파형 인코딩 및 전처리, 부채널 누출신호 탐색 등으로 연구범위가 확대되어지고 있다. 본 논문에서는 딥러닝을 이용한 부채널 분석 기술의 최신 연구 동향을 분야별로 체계적으로 정리 및 분석하고자 한다.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05a
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• pp.577-581
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• 1996

고분자 촉매를 이용하여 용존산소를 제거하는 실험을 수행하였다. 고분자 촉매는 높은 비표면적과 좋은 금속의 분산도를 갖도록 제조하였다. 컬럼에서 제조된 촉매를 사용하여 용존산소-수소의 반응을 수행한 결과 용존산소를 35 ppb까지 감소시킴으로서 제조된 촉매의 용존산소제거에의 적합성을 확인하였다. 컬럼에서의 촉매의 거동을 적절한 모델을 통하여 해석하였으며 또한 활성탄에 담지된 금속 촉매 및 현재 상용화되고 있는 Lewatit촉매를 이용하여 실험을 수행함으로서 촉매성능을 비교하였다. 활성탄의 경우 초기에 활성탄의 표면에 산소가 많이 흡착되어 있기때문에 이를 제거하기 위하여 전처리가 필요한 것으로 나타났으며 Lewatit촉매의 경우 가장 우수한 성능을 보였다.

• Korean Journal of Food Science and Technology
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• v.29 no.2
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• pp.337-342
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• 1997

In order to compare methods of making a mead and a melomel, changes of alcohol contents, reducing sugar, soluble solids, pH and total acidity during fermentation of a mead and Japanese plum melomel was investigated. Fermentation rate of the melomel were much faster than the mead. Reducing sugar and soluble solids were continuously decreased until the 16th day of fermentation, while alcohol contents were increased continuously during the same period. After fermentation of 21 days, alcohol contents of the mead was reached 7.6%, while that of the Japanese plum melomel reached 12.4%. pH and total acidity were not changed considerably during the whole fermentation period. Clear honey wines with transmittance of 99.4% were obtained by membrane filtration. In conclusion, the method of making melomel using the osmotically extracted fruit juice with honey was found to be more advantageous than the method of making a simple mead.

• KSBB Journal
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• v.22 no.3
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• pp.151-156
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• 2007

Increasing public concerns over odors and air regulations necessitates the remediation of a wide range of odorous compounds for industrial purpose. Currently, wet scrubbing technique by neutralization using essential oils is utilized to treat methyl mercaptan odor. The chemical analysis is performed to analyze the composition of an essential oil by GC-MS. The objective of this study is to clarify the possibility of the neutralization of odors sprayed in the fixed bed and determine the removal efficiencies in the misty aerosol by different input odor concentration. It is found that methyl mercaptan is significantly removed in the wet scrubber, and their removal efficiency of methyl mercaptan is obtained by 98%.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.4
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• pp.651-659
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• 2000

The characteristics of ammonia removal by natural neutralizer were studied by using a scrubber type equipment. As operation parameters, neutralizer dilution ratio, neutralizer inlet flowrate, air flowrate and initial ammonia concentration were selected and their effects on ammonia removal efficiency were investigated. The optimal removal effect was achieved at neutralizer dilution ratio of 1.0% and neutralizer inlet flowrate of $60m{\ell}/min$. On the other hand, with respect to air flowrate and initial ammonia concentration, there was no significant effect on removal efficiency, when loading rate was considered. In addition, ammonia removal reaction was investigated by analyzing the ammonia oxides, such as nitrites and nitrates, after reacting ammonium solution with natural neutralizer. The result shows a partial oxidation by natural neutralizer besides dominant absorption of ammonia.

• Proceedings of the KAIS Fall Conference
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• 2004.11a
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• pp.288-291
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• 2004

강우유출수의 오염기원별 기여도를 파악하고자 홍제천 유역의 구기 배수분구를 대상으로 강우시 유량 및 오염물질 발생경향 및 오염기원별 오염도 분석 등에 대하여 살펴보았다. 강우시 발생초기의 오염물질의 농도는 강우에 의한 초기세척현상(First Flush)에 의해 상당히 높게 나타났으며, 강우초기의 높은 오염물질의 농도는 강우에 의해 희석되어 일시적으로 낮아졌다가 높은 강우강도에 의하여 급격히 상승하였으며, 이후 오염물질의 농도는 유량의 감소에 따라 점차적으로 감소하는 것으로 나타났다. 물질수지식을 이용한 근사적인 오염부하의 오염원별 기여도 분석에서 관거 퇴적물에 의한 오염도가 COD $27.7\%$, SS $47.5\%$로 나타났으며 지역에 따라서는 건기 하수보다도 더 높은 기여도를 보이고 있어 월류수 오염부하의 제어측면에서 정기적인 관거내 퇴적물의 준설과 세정을 통하여 상당량의 오염부하를 저감시킬 수 있는 것으로 나타났다.

• KSBB Journal
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• v.14 no.4
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• pp.465-469
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• 1999

Horseradish peroxidase(HRP) in organic solvent can be reactivated by evaporation. In order to measure the evaporation effect, the enzyme solutions were obtained by evaporation and dilution of organic solvent, respectively. Although two situations were thermodynamically identical, the activity from evaporation was higher than that from dilution. From the UV absorbance and the fluorescence intensity mesurements, it can be explained that reactivation of enzyme activity might be caused by reversible folding, and the enzyme obtained by evaporation was more refolded than that obtained by dilution.

• Polymer(Korea)
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• v.28 no.1
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• pp.35-40
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• 2004

The formation mechanism of void defect which deteriorate composite's property is various according to each composite process. In this paper, void formation and growth mechanism is analyzed by thermal analysis and GC/MS. We made a vacuum chamber for observing pressure effect. Thermal analysis has been done in various condition. Elements of volatiles during resin curing were turned out by GC/MS. The most of volatiles of polyester were composed of styrene (over 80%) and a small quantity of toluene. In case epoxy resin, butyl glycidyl ether was the main element of volatiles (over 90%). We concluded that the original sites of void growth existed in resin and they were eliminated by vacuum and heating process. And the growth of void was influenced by water, diluents, solvent, and reactants in resin.