• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2001.11a
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• pp.67-72
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• 2001

오랜 동안의 경험으로부터 조건설정이 표준화되어 있는 석유화학공업과는 달리 정밀화학공업에 있어서는 대상이 되는 공정의 반응조건 등을 제조자 스스로 결정해야 하는 경우가 많다. 또한, 취급하는 화학물질의 열분해 또는 반응위험성에 대한 위험성평가는 물론 물질안전자료(MSDS)도 확보되지 않은 상태에서 취급되는 경우가 많아 폭발ㆍ화재로 인한 중대재해의 잠재적 위험성이 매우 높은 상태이다.(중략)

• Applied Chemistry for Engineering
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• v.21 no.1
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• pp.1-5
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• 2010

Cu(II)-organic complexes were synthesized with Lewis base organic ligands including diamine, aminothiol, and dithiol to determine the reactivity for DFP hydrolysis. Results show that the aminothiol catalyst enhances the hydrolysis of DFP in three folds compared to diamine type because aminothiol has higher basicity than diamine. Due to low solubility of Cu(II)(1,2-ethane dithiol)$(NO_3)_2$, it is impossible to compare directly the rates in homogeneous condition. However, the rate of dithol complex is even 1.6 times faster than that of the diamine type. The reactivity of zeolite for DFP hydrolysis is also evaluated. NaY type does not promote the hydrolysis, but RuNaY shows relatively lower reactivity than those of Cu(II)-organic ligands complexes.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.12
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• pp.163-173
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• 2014

When evaluating the spatial resolution images and evaluation of low contrast resolution using CT standard phantom, and might present a automated quantitative evaluation method for minimizing errors by subjective judgment of the evaluator be, and try to evaluate the usefulness. 120kVp and 250mAs, 10mm collimation, SFOV(scan field of view) of 25cm or more than, exposure conditions DFOV(display field of view) of 25cm, and were evaluated the 24 passing images and 20 failing images taken using a standard reconstruction algorithm by using the Nuclear Associates, Inc. AAPM CT Performance Phantom(Model 76-410). Quantitative evaluation of low contrast resolution and spatial resolution was using an evaluation program that was self-developed using the company Mathwork Matlab(Ver. 7.6. (R2008a)) software. In this study, the results were evaluated using the evaluation program that was self-developed in the evaluation of images using CT standard phantom, it was possible to evaluate an objective numerical qualitative evaluation item. First, if the contrast resolution, if EI is 0.50, 0.51, 0.52, 0.53, as a result of evaluating quantitatively the results were evaluated qualitatively match. Second, if CNR is -0.0018~-0.0010, as a result of evaluating quantitatively the results were evaluated qualitatively match. Third, if the spatial resolution, as a result of using a image segmentation technique, and automatically extract the contour boundary of the hole, as a result of evaluating quantitatively the results were evaluated qualitatively match.

• Journal of radiological science and technology
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• v.39 no.4
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• pp.631-636
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• 2016

Hitherto, spatial resolution has commonly been evaluated by test patterns or phantoms built on some specific distances (from close to far) between two objects (or double targets). This evaluation method's shortcoming is that resolution is restricted to target distances of phantoms made for test. Therefore, in order to solve the problem, this study proposes and verifies a new method to efficiently test spatial resolution with a single target. For the research I used PSF and JND to propose an idea to measure spatial resolution. After that, I made experiments by commonly used phantoms to verify my new evaluation hypothesis inferred from the above method. To analyse the hypothesis, I used LabVIEW program and got a line pixel from digital image. The result was identical to my spatial-resolution hypothesis inferred from a single target. The findings of the experiment proves only a single target can be enough to relatively evaluate spatial resolution on a digital image. In other words, the limit of the traditional spatial-resolution evaluation method, based on double targets, can be overcome by my new evaluation one using a single target.

• Proceedings of the Korean Information Science Society Conference
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• 2003.10a
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• pp.757-759
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• 2003

저장장치의 발전과 인터넷 사용량의 증가, 전자 상거래의 활성화에 의해 많은 사람들이 디지털정보를 편리하게 이용할 수 있게 되었다. 이에 따라 저장장치의 보안성과 생존성은 가장 중요한 사항으로 고려되고 있으며, 이러한 보안성과 생존성을 높이기 위하여 새로운 분산저장기법의 연구개발이 절실히 필요한 실정이다. 따라서, 본 논문에서는 분산저장시스템의 보안성과 생존성을 높이기 위해 필수적으로 필요한 분산/암호화 기법을 LDU 분해를 이용하여 제안하고, 제안된 기법의 가용성을 평가한다 제안된 기법은 데이터의 분할과 암호화를 동시에 허락하여 보안성을 높임과 동시에 기존의 기법과 비교하여 10%정도의 가용성 향상을 보인다.

• Journal of Wetlands Research
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• v.6 no.1
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• pp.117-132
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• 2004

Despite its significance in understanding ecological structure and biogeochemical element cycles, there have been few studies on the microbial mineralization of organic matter and mineralization pathway in the intertidal flat of Korea. We measured anaerobic mineralization of organic matter and sulfate reduction rate, and evaluated the significance of sulfate reduction in total anaerobic carbon respiration at the southern part of Ganghwa Island. Depth-integrated carbon mineralization rate down to 6 cm depth ranged from 41.9 to $89.4mmol\;m^{-2}d^{-1}$, which accounted for approximately 216 tons of organic matter mineralization in entire intertidal flat area of Ganghwa($300km^2$). The results indicated that capacity for the organic matter mineralization in the Ganghwa tidal flat is comparable to highly productive salt marsh environments. Mineralization rates in the sediment amended with acetate were 2~5 times higher than in unamended sediment. The results implied that microbial mineralization was limited by the availability of organic substrates, and the organic matter mineralization capacity seems to be higher than estimated at ambient organic substrate level. Depth-integrated sulfate reduction rates within 6 cm depth of the sediment ranged from 20.7 to $45.1mmol\;SO{_4}^{2-}m^{-2}d^{-1}$, and sulfate reduction was mostly responsible for organic matter remineralization. It should be noticed that the increase of $H_2S$ in the sulfate reduction dominated tidal flat may result in the decrease of biological diversity.

• Korean Journal of Food Science and Technology
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• v.16 no.2
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• pp.228-234
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• 1984

A partial hydrolysis of soybean protein isolate was carried out by using pepsin and trypsin. The degree of hydrolysis was evaluated by chemical analysis, viscometric measurements and gel electrophoresis. The functional properties of the hydrolyzates such as flow behavior, emulsion properties and foaming properties were evaluated. A selective hydrolysis of 11S protein fraction by pepsin was observed from the SDS-PAG electrophoresis. The changes in the molecular weight distribution by different conditions of enzyme hydrolysis were evaluated. The changes in the intrinsic viscosity of the protein hydrolylate by reaction time were highly correlated to the contents of TCA soluble protein and 0.03 M $CaCl_2$ soluble nitrogen. The degree of hydrolysis ($DH_{TCA}$, $DH_{Ca}$) were used to evaluate the effect of enzyme treatment on the functional properties of the hydrolyzate. The apparent viscosity and emulsion capacity and stability of the protein solution decreased as DH increased, while the foaming capacity increased linearly with the increasing DH.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2011.03a
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• pp.54-54
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• 2011

방사 공정 최적화를 위해 칩(chip)건조를 실시하여 칩의 수분을 모두 제거한 후 실험을 진행하게 된다. 칩은 그 자체가 공정수분율(0.4%) 또는 그 이상의 수분을 함유하고 있으므로 건조하지 않고 방사하면 현저히 가수분해가 일어난다. 가수분해가 일어난다면 PET 분자량도 저하되어 고분자의 성질을 잃게 되어 방사된 섬유의 물리 화학적 성질에 중요한 영향을 받게 된다. 그러므로 가수분해를 방지하기 위하여 칩내 수분을 제거하는 건조 공정을 거치는 것이다. 개발된 나노은입자을 함유한 Ag/PET 마스터배치의 제사성 및 가연성 평가을 위한 파일럿연구를 행했다. 본 연구에서 사용한 은나노 M/B 칩(chip)의 경우 일반적으로 사용하는 PET 칩에 비하여 낮은 고유점도를 가지므로 방사성에 칩의 수분이 더욱 영향을 미칠 것이라 판단되어 건조공정에 특별한 주의을 하여 진행하였다. 마스터배치의 고유점도(IV)값의 변화에 따른 제사성 및 가연성 평가를 관찰하였다. #3 M/B 칩의 제사성이 #1 M/B 칩 대비 공정성이 개선되어 두 품종 모두 비출사가 발생하지 않았으며, M/B 제조시 분산제 유무에 따른 방사공정성의 차이는 없는 것으로 보인다. 따라서 #1 M/B 대비 공정성이 개선된 점은 M/B의 IV개선에 기인하는 것으로 판단되었다.

• Membrane Journal
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• v.25 no.3
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• pp.287-294
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• 2015

Photovoltaic (PV) modules are environmentally friendly energy-conversion devices to generate electricity via the photovoltaic effect of semiconductors on solar energy. One of key elements in PV modules is "Backsheet," a multi-layered film to protect the devices from a variety of chemicals including water vapor. A representative Backsheet is composed of polyvinyl fluoride (PVF) and poly(ethylene terephthalate) (PET). PVF is relatively expensive, while showing excellent resistance to chemical attacks. Thus, it is necessary to develop alternatives which can lower its high production cost and guarantee lifetime applicable to practical PV modules at the same time. In this study, PET films with certain levels of crystallinity were utilized instead of PVF. Since it is well known that PET is suffering from trans-esterification and hydrolysis under a wide pH range, it is needed to understand decomposition behavior of the PET films under PV operation conditions. To evaluate their chemical decomposition behavior within a short period of times, accelerated decomposition test protocol is developed. Moreover, electrochemical long-term performances of the PV module employing the PET-based Backsheet are investigated to prove the efficacy of the proposed concept.

• Journal of the Korea Organic Resources Recycling Association
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• v.29 no.4
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• pp.99-106
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• 2021

The purpose of this study was to evaluate the performance of novel process with thermal hydrolysis and separation as pre-treatment of anaerobic digestion (AD). The dewatered sludge was pre-treated using THP, and then separated. The separated liquid used as substrate for AD and separated solid was returned on THP(Thermal Hydrolysis Process). The degree of disintegration (DD, based on COD) using only THP found 45.1-49.3%. The DD using THP+separation found 76.1-77.6%, which was higher than only THP. As result from dual-pool two-step model, the ratio of rapidly degradable substrate to total degradable substrate found 0.891-0.911 in separated liquid, which was higher than only THP. However, the rapidly degradable substrate reaction constant (kF) of only THP and THP+separation were similar. This results found that dewatered sludge was disintegrated by THP, and then rapidly degradable substrate of hydrolyzed sludge was sorted by separation.