• 한국재난정보학회 논문집
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• 제17권4호
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• pp.897-903
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• 2021

연구목적: 최근 국내외에서 해킹으로 피해자의 데이터를 암호화하고 이를 풀어주는 대가로 금전적 대가를 요구하는 랜섬웨어 피해가 증가하고 있다. 이에 다양한 방식의 대응기술과 솔루션에 대한 연구개발이 진행되고 있으며, 본 연구에서는 데이터를 저장하는 저장장치에 대한 보안 연구개발을 통해 근본적인 대응방안을 제시하고자 한다. 연구방법: 동일한 가상환경에 보안 저장영역과 일반 저장영역을 생성하고 접근 프로세스를 등록하여 샘플 데이터를 저장하였다. 저장된 샘플 데이터의 침해 여부를 확인하기 위해 랜섬웨어 샘플을 실행하여 침해 여부를 해당 샘플 데이터의 Hash 함수를 확인하였다. 접근 제어 성능은 등록된 접근 프로세스와 동일한 이름과 저장위치를 통해 샘플 데이터의 접근 여부를 확인하였다. 연구결과: 실험한 결과 보안 저장 영역의 샘플 데이터는 랜섬웨어 및 비인가된 프로세스로부터 데이터의 무결성을 유지하였다. 결론: 본 연구를 통해 보안 저장영역의 생성과 화이트리스트 기반의 접근 제어 방법이 중요한 데이터를 보호하는 방안으로 적합한 것으로 평가되며, 향후 기술의 확장성과 기존 솔루션과의 융합을 통해 보다 안전한 컴퓨팅 환경을 제공할 수 있을 것으로 기대된다.

• 한국식품조리과학회지
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• 제16권6호
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• pp.511-520
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• 2000

약포의 첨가당과 건조방법이 육포의 품질과 저장성에 미치는 영향을 알아보기 위하여 저장상, 기계적 특성과 관능검사를 실시하였다 육포의 저장 기간 중에 수분활성 도는 경시적으로 감소경향을 나타내었고 저장 5주에는 꿀과 조청을 첨가한 천연건조시료(N-H, N-R)가 모두 0.71로 가장 낮은 값을 보였다. 모든 시료의 pH는 저장에 따라 감소하였으며 꿀을 첨가하여 열풍 건조한 육포(H-H)가 5.22로 가장 낮았다. 색도의 L, a, b값은 저장기간 중에 모두 감소 경향을 보였다. 저장기간 중 모든 시료에 있어서 TBA값이 증가하는 것으로 나타났고, 설탕시립첨가육포(N-S, H-S, S-S)는 건조방법과 관계없이 가장 낮은 값을 보였으며 꿀첨가육포(N-H, H-H, S-H)가 가장 높았다. 모든 시료의 총미생물수와 젖산균수는 저장 기간이 경과함에 따라 증가하였으며, 저장 5주시 설탕시럽첨가 열풍건조한 육포(H-S)가 가장 낮았다. 모든 시료의 기계적 조직특성은 저장기간이 경과함에 따라 증가하였다. 탄력성과 응집성은 대체로 꿀첨가시료가 가장 높았고 씹힘성과 점착성·견고성은 설탕시럽첨가 천연건조 시료가 가장 높게 나타났다. 천연건조시료는 포장방법에 관계없이 거의 모든 항목에 걸쳐 저장기간이 경과함에 따라 관능점수가 감소하였고, 열풍건조시료들의 관능점수는 포장방법에 관계없이 천연건조시료들에 비해 현저히 높은 점수를 나타내었다.

• 한국식품영양과학회지
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• 제29권4호
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• pp.582-585
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• 2000

This study was performed to identify the flavor compnenets of Korean Cnidium officinale M.. The extraction of the flavor compounds of Cnidium officinale M. was accomplished by a simultaneous distillation and extraction method using a Likens and Nickerson's extraction apparatus. The concentrated extract was analyzed and identified by gas chromatography and GC-mass spectrometry. The change of the 림팩 contents in each samples was determined in terms of two different storage conditions. The flavor contents of sample at low temperature storage were higher than those at room temperature storage, and increased until storage period of 70 days. The major components of Cnidium officinale M. were terpene compounds including α-pinene, β -selinene, γ-selinene, and phthalides including butylidenephthalide, cnidilide, neocnidilide, senkyunolide A, ligustilide, which are believed to contribute to the characteristic flavor of the Cnidium officinale M.. Especially, great amount of cnidilide and ligustilide was shown in sample of low temperature storage.

• 대한치과보철학회지
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• 제36권3호
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• pp.453-467
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• 1998

This study helps to clarify conflicting reports by comparing the physical properties and accuracy of complete denture processed by the pack and press technique, continuous- pressure injection technique(SR-Ivocap system) and Mark press technique. The 6 different specimens have been evaluated using the SEM, Impact test, DSC (Differential Scanning Calorimetry) and DMTA (Dynamic Mechanical Thermal Analysis). Each sample was made of SR-Ivocap resin and QC-20 resin by different processing methods. The results were as follows ; 1. As the result of the observation on the fracture surface of resin by use of SEM, sample SR-Ivocap resin cured by continuous pressure injection method showed the most homogeneous structure. This is why molecules in SR-Ivocap resin have no orientation. 2. As the result of the Impact test in order to measure the deformity, fracture energy and impact resistance of resin, the samples with QC-20 acrylic resin and SR-Ivocap resin cured by continuous pressure injection method were exellent. 3. In consequence of measuring ${\alpha}$-glass transition temperature by use of DSC on the basis of temperature change, the glass transition temperatures of sample QC-20 resin cured by pack and press method and sample SR-Ivocap resin cured by continuous pressure injection method were very similar. Thus volumetric stability could not be evaluated only by glass transition temperature. 4. In comparing volumetric stability data by DMTA, the glass transition temperature(Tg) showed $137.88^{\circ}C$ at sample QC-20 resin cured by pack and press method and $139.78^{\circ}C$ at sample SR-Ivocap resin cured by continuous pressure injection method. Therefore sample SR-Ivocap resin cured by continuous pressure injection method seems to be superior to sample QC-20 resin cured by pack and press method in the dimensional stability at high temperature. 5. In comparing storage modulus data by DMTA, the storage modulus of sample SR-Ivocap resin cured by continuous pressure injection method was higher than that of sample QC-20 resin cured by pack and press method. So. sample SR-Ivocap resin cured by continuous pressure injection method seems to be superior to sample QC-20 resin cured by pack and press method in impact strength.

• 한국식품영양학회지
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• 제10권2호
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• pp.145-150
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• 1997

본 연구는 유자과즙과 유자를 이용한 제품개발시 기초자료로서의 활용을 목적으로, 생유자를 벨트식 착즙법9)으로 착즙한 유자 과즙(Sample I)과 이를 5$^{\circ}C$에서 1년간 저장한 유자 과즙(Sample II)의 품질특성을 비교 분석한 결과, Sample II는 Sample I에 비하여 수분은 3% 정도의 증가를 보였고, soluble solid가 1$^{\circ}$brix 이상 감소되었다. pH는 2.68에서 2.84로 증가하면서 산도가 5.83에서 5.23으로 감소되었다. 비타민 C는 50% 이상 감소하였고, 총아민산 및 유리아미노산의 함량은 약 20~30% 정도의 감소를 보였으나, 그 밖의 일반성분들과 유리당, 지방산 및 총아미노산 함량의 감소는 0.1~1.0% 정도로 변화 정도가 미미하였다. 그리고, Sample I과 II의 향기성분을 gas chromatograpy로 비교 분석한 결과, 분리된 peak의 수는 70여 개인데, mass spectrometer로 확인할 수 있는 성분은 13개에 불과하였고, 주된 향기성분은 탄화수소류로 limonene, terpinene, terpineol, terpinolene 등이다. 1년간 저장함에 따라서 향기성분은 약 30~50% 정도 감소되고, 미량 함유되어 있던 성분들은 거의 소실되는 것으로 나타났으나, Sample I 및 II로 10% 희석음료로 제조하여 관능검사한 결과 당배합비 및 저장기간에 따른 유의차는 거의 나타나지 않았다.

• 한국식품영양학회지
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• 제11권4호
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• pp.444-451
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• 1998

The changes of amine, nitrate and nitrite nitrogen in yellow corvenia were studied during its processing and storage in order to clarify the precursors of N-nitrosamine(NA) formation in the salted and dried yellow corvenia(Gulbi), prepared y using the different salting method like dry and brine salting by pure and curde salt. As a result, during the processing and storage of Gulbi, DMA and TMA contents were significantly increased in the yellow corvenia. And after 40 days storage the increase rate showed 25.7∼45.7, 3.3∼5.6 times higher than those of 0.3, 2.4mg/kg, respectively, while nitrite contents, during its processing and storage, were scarcely changed in the salted and dried yellow corvenia. During the processing and storage, of Gulbi, DMA and TMA contents were less produced in brine salted and dried yellow corvenia using crude salt than in sample prepared using were scarcely changed in the salted and dried yellow corvenia. During the processing and storage of Gulbi, DMA and TMA contents were less produced in brine salted and dried yellow corvenia using crude salt than in sample prepared using pure salt, while the former were more effective than the latter in inhibiting the production of nitrate and nitrite. Therefore, it was revealed that reduction of NA precursors such as DMA, TMA, nitrate and nitrite were more effective in preparing with the brine salting method than with the dry salting method.

• 한국환경성돌연변이발암원학회지
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• 제15권2호
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• pp.115-121
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• 1995

Bacterial mutagenicity of shellfish or canned products of red-muscle fish affected by hot-airdry processings and/or during storages was investigated by Ames preincubation method. Mussel (Mytilus edulis) and surf clam (Tapes japonica) dried under either 40$\circ$C, 50$\circ$C or 60$\circ$C until remained about 25 % water content was stored at 4$\circ$C or 25$\circ$C for 6 months. Commercially available canned product of pacific saury (Cololabis saira) and mackerel saury (Scotnberjaponicus), whose producer or date of manufacture was identical each other, was stored at 25$\circ$C for 6 months. Mutagenic substances from sample (25 g dry weight) were extracted and purified for mutagenicity assay against S. typhitnurium TA98 by the simultaneous distillation extraction (SDE) method (Lee et al. 1955). Mutagenicity of sample was expressed number of revertant per 25 g dry sample. Number of revertant from unheated mussel sample was appeared to be 135, relative to 22 from unheated surf clam sample. Mutagenicity of both shellfish was strongly affected by heat treatment, but a lesser extent by storage conditions, even at 25$\circ$C for 6 months. Revertants of the mussel sample dried at 40$\circ$C, 50$\circ$C, or 60$\circ$C was found to be 227, 779, and 883, respectively. Similar, but lower, mutagenicity was observed from the sample of surf clam dried at 40$\circ$C, 50$\circ$C, or 60$\circ$C than mussel. Mutagenicity of canned pacific saury and mackerel samples was not influenced by storage conditions. Number of revertant from pacific saury was 175 which was relatively higher than 5 from mackerel. Mutagenicity of fresh pacific saury and mackerel samples was significantly higher than that of their counterparts from canned products. These results indicate that mutagenicity of the shellfish was affected by heat treatment (40$\circ$C, 50$\circ$C, or 60$\circ$C) used for drying process, but not much by storage for 6 months at 4$\circ$C or 25$\circ$C and the mutagenicity of canned products of red-muscle fish was not influenced by storage, even at 25$\circ$C for 6 months.

• 한국신뢰성학회지:신뢰성응용연구
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• 제16권1호
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• pp.32-40
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• 2016

Purpose: The purpose of this study is to analyze the effect of sampling points on accuracy of storage reliability estimation for one-shot systems by assuming a weibull distribution as a storage reliability distribution. Also propose method for determining of sampling points for increase the accuracy of reliability estimation. Methods: Weibull distribution was divided into three sections for confirming the possible to estimate the parameters of the weibull distribution only some section's sample. Generate quantal response data for failure data. And performed parameter estimation with quantal response data. Results: If reduce sample point interval of 1 section, increase the accuracy of reliability estimation although sampling only section 1. Even reduce total number of sampling point, reducing sampling time interval of the 1 zone improve the accuracy of reliability estimation. Conclusion: Method to increase the accuracy of reliability estimation is increasing number of sampling and the sampling points. But apply this method to One-shot system is difficult because test cost of one-shot system is expensive. So propose method of accuracy of storage reliability estimation of one-shot system by adjustment of the sampling point. And by dividing the section it could reduce the total sampling point.

• 대한금속재료학회지
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• 제49권4호
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• pp.298-303
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• 2011

Mg-23.5 wt%Ni-xwt%Cu (x = 2.5, 5 and 7.5) samples for hydrogen storage were prepared by melt spinning and crystallization heat treatment from a Mg-23.5 wt%Ni-5 wt%Cu alloy synthesized by the gravity casting method. They were then ground under $H_2$ to obtain a fine powder. Among these samples the Mg-23.5Ni-2.5Cu sample had the highest hydriding and dehydriding rates after activation. The Mg-23.5Ni-2.5Cu sample absorbed 3.59 and 4.01 wt%H for 10 and 60 min, respectively, at 573K under 12 bar $H_{2}$. The activated 88(87.5Mg-10Ni-2.5Cu)-$5Nb_{2}O_{5}-7NbF_{5}$ sample absorbed 2.93 wt%H for 10 min, and 3.14 wt%H for 60 min at 573K under 12 bar $H_{2}$.

• 한국대기환경학회지
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• 제28권3호
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• pp.306-315
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• 2012

In this study, storage stability of reduced sulfur compounds ($H_2S$, $CH_3SH$, DMS, $CS_2$, and DMDS) and $SO_2$ in sampling bags was investigated in terms of two contrasting storage approaches between forward (F) and reverse (R) direction. The samples for the F method were prepared at the same time and analyzed sequentially through time. In contrast, those of reverse (R) method were prepared sequentially in advance and analyzed all at once upon the preparation of the last sample. In addition, relative performance between two different bag materials (PVF and PEA) was also assessed by using 100 ppb standard. The response factors (RF) of gaseous RSC samples were determined by gas chromatography/pulsed flame photometric detector (GC/PFPD) combined with air server (AS)/thermal desorber (TD) system at storage intervals of 0, 1, and 3 days. There is no statistical difference in all RSCs between two storage methods. However, the results of relative recovery indicated 2.58~12.8% differences in compound type between the two storage methods. Moreover, loss rates and storage stability of $H_2S$ and $SO_2$ were considerably affected by bag materials than any other variables. Therefore, some considerations about storage methods (or bag material types) for sulfur compounds are needed if stored by sampling bag method.