• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.307-307
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• 2008

전자부품에서 기존에 봉착, 코팅, 결합용 glass frit로 사용되어 왔던 Pb계 glass frit는 낮은 융점을 가지고 있고, 화학적으로도 매우 안정한 특성을 가지고 있다. 그러나 Pb계 glsss frit은 환경에 심각한 문제를 초래하기 때문에 이를 대체하기 위하여 저온에서 소성이 가능한 인산주석계를 기본조성계로 설정하였다. 인산주석계 glass의 취약한 내화학성, 내수성과 SnO의 환원에 의한 결정 석출 등의 문제를 해결하기 위하여 $R_2O_3$, RO 등을 첨가하여 glass frit의 특성을 향상시키고자하였다. 수분에 취약한 $P_2O_5$계 glass의 $R_2O_3$를 첨가하여 항온항습기를 이용하여 흡습성을 측정하고, 내수성에 가장 안정한 특성을 보이는 SnO-$P_2O_5-R_2O_3$ 계 glass 조성에 RO를 첨가하여 RO 첨가량에 따른 내산성과 내알칼리성의 변화를 관찰하였다. SnO-$P_2O_5-R_2O_3$계 glass의 RO첨가량에 따른 melting 특성의 변화를 flow-button test를 통해 관찰하였다. SnO-$P_2O_5-R_2O_3$계는 RO계의 변화에 따라 전이온도가 증가하고, 열팽창계수가 감소하는 결과를 보였다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.05a
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• pp.159-161
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• 2013

Surveillance system that can respond quickly in case of failure to detect various disorders that can occur for a temperature chamber, and fire extinguishing equipment, such as UPS, communication room, and computer room of enterprises and institutions operating in infrastructure, and to systematically study. Major telecommunications equipment and computational facilities to manage, operating in an environment of air conditioners work status, distribution panel and the UPS status and fault status, rapid notification system in case of fire is needed. By identifying the status and problems of disability surveillance on the periphery of the existing computer room's infrastructure management guidelines presented in the next future Conception and systematic surveillance system for staff to refer to when designing considerations associated with data center monitoring system the necessity of the various studies are presented.

• Journal of the Korea Society of Computer and Information
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• v.19 no.2
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• pp.11-19
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• 2014

In this paper, we build server consolidate virtualization focusing on NT server dilapidated and through analysis of the effect of this, has been presented the following results. First, it was possible to obtain an increase in the constant temperature constant humidity chamber efficiency by securing the upper surface space for computing data center mounted virtualization integration server servers multiple physical. Second, by the deployment of virtualization of a large server dilapidated, the introduction of new resources and the cost of maintaining computerized data center and reduce power consumption, the reduction of hardware introduction of additional due to the new server deployment it was possible to derive a cost reduction effect. We obtain the reduction of 89% and 79% compared with conventional consumption of cooling and power savings of the top surface, respectively. Integration of NT servers are virtualized can be expected to change in the Green-IT to contribute to providing the maintenance costs of computing centers in the future as well as current. Building a virtualization server integration applied in this paper can be similarly applied to the UNIX system and to integrate the server group other.

• Journal of the Korean Society for Nondestructive Testing
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• v.36 no.3
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• pp.225-230
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• 2016

Fiber Bragg grating (FBG) sensors are currently the most prevalent sensors because of their unique advantages such as ease of multiplexing and capability of performing absolute measurements. They are applied to various structures for structural health monitoring (SHM). The signal characteristics of FBG sensors under thermal loading should be investigated to enhance the reliability of these sensors, because they are exposed to certain cyclic thermal loads due to temperature changes resulting from change of seasons, when they are applied to structures for SHM. In this study, tests on specimens are conducted in a thermal chamber with temperature changes from -$20^{\circ}C$ to $60^{\circ}C$ for 300 cycles. For the specimens, two types of base materials and adhesives that are normally used in the manufacture of packaged FBG sensors are selected. From the test results, it is confirmed that the FBG sensors undergo some degree of compressive strain under cyclic thermal load; this can lead to measurement errors. Hence, a pre-calibration is necessary before applying these sensors to structures for long-term SHM.

• Journal of the Korean Wood Science and Technology
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• v.30 no.4
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• pp.41-50
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• 2002

Small clear specimens of Quercus acutissima Carr. and Larix caempferi Carr. were used to measure shrinkage and thermal conductivity for the reasonable and effective use. All samples were conditioned to 18, 12, 5% moisture contents in a humidity chamber of 86, 66, 20% relative humidity(RH), respectively and room temperature(23℃) All specimens were conducted on the shrinkage and thermal conductivity test at each MCs. These processes(cycle) were repeated three times. The radial and tangential shrinkages of Quercus acutissima Carr. and Larix caempferi Carr. decreased at each level of MCs, with the increasing cycles. The radial and tangential shrinkages increased as the specific gravity(on oven-dry weight and volume basis) increased. Thermal conductivities of the radial and tangential direction of Quercus acutissima Carr. and Larix caempferi Carr. increased at each levels of MCs, with increasing cycles. Good correlations were obtained between shrinkages and thermal conductivities of radial and tangential direction, and specific gravity (on oven-dry weight and oven-dry volume basis) and MC.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.33-33
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• 2017

본 연구는 온실 $CO_2$ 공급용 Membrane Module이 대기 중 $CO_2$를 포집하는 과정에서 유해병원균을 제거할 수 있는지 알아보기 위해 실험을 진행하였다. 본 실험은 Membrane Module과 유해병원균의 유무로 총 4개의 실험구, 포집하는 시간에 따라 1 min, 3 min, 5 min, 각각 3회씩, 총 36회의 실험을 진행하였다. 실험은 경상대학교 내 온실($W{\times}D{\times}H$, $3000{\times}4000{\times}2500mm$)에서 진행하였고, 유해병원균은 잎점무늬병을 일으키는 병원균(Phoma sp.)을 사용하였다. 온실에 Membrane System을 설치하고 Membrane Module을 통해 외부공기 또는 유해병원균이 포함된 공기를 분리하여 온실 내로 공급하고, 공급한 $CO_2$ 내에 유해병원균의 유무는 에어샘플러를 이용하여 온실 내의 공기를 포집 후 배지에 배양하여 확인하였다. 유해병원균은 PDA배지를 이용하여 포집한 뒤 항온항습기(HB-105SG-O, HANBAEK SCIENTIFIC CO., Korea)에 $25^{\circ}C$, 50%로 48시간 배양하였다. PDA배지 내에 배양된 미생물은 Colony Counter(HYC-560, CORETECH, Korea)로 측정하였다. 결과 값을 분석하기 위해서 IBM SPSS Statistics의 이원분산분석(two-way ANOVA)을 이용하여 통계분석 하였다. 결과 값은 유해병원균을 공급하고 Membrane Module을 사용하지 않았을 때, CFU(Colony-Forming Unit)가 가장 높았고, 유해병원균을 공급하고 Membrane Module을 사용했을 때 CFU가 가장 낮았다. 통계분석을 실시한 결과, Membrane Module을 사용하지 않은 실험구에는 유의한 차이가 나타났고, Membrane Module을 사용한 실험구에는 유의한 차이가 나타나지 않았다. 따라서 Membrane Module이 대기 중 $CO_2$를 분리하여 온실에 공급하는 과정에서 공기 중에 포함된 유해병원균을 제거 할 수 있다고 판단된다.

• Journal of Adhesion and Interface
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• v.21 no.2
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• pp.65-70
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• 2020

Epoxy adhesive was mainly used to combine different composite materials. Epoxy adhesive was a typical thermosetting resin that can be bonded by changing from a linear structure to a three-dimensional network structure by curing reaction of epoxy and hardener. The curing conditions of epoxy adhesive were different with different types of hardener such as mixing ratio, curing time, and temperature. These curing conditions affected to the adhesive property of epoxy adhesive. In industry, it was difficult to proceed the applying epoxy adhesive and combining two parts immediately. The adhesive property decreased by humidity and pre-curing of epoxy adhesive in waiting time between two processes. In this paper, the glass fiber reinforced composite (GFRC) was combined with epoxy adhesive and adhesion property between epoxy adhesive and GFRCs was evaluated using single lap shear test. The different waiting times and humidity conditions were applied to epoxy adhesive in room temperature and adhesive property decreased as the waiting time increased. In small amount of humidity, the adhesive property increased because a small amount of moisture in the surroundings accelerated the curing reaction. In certain amount of humidity, however, the adhesion property decreased.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.3
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• pp.425-433
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• 2015

This study investigated changes in physicochemical characteristics by drying and fermentation in order to utilize Actinidia arguta. Moisture content of A. arguta was 85.81%. Major sugar and organic acids were sucrose, succinic acid, and citric acid. A. arguta contained 19 kinds of amino acids, including 8 kinds of essential amino acids such as valine, methionine, isoleucine, leucine, threonine, phenylalanine, tryptophan, and lysine. For total organic acids, sample fermented for 17 h at $50^{\circ}C$ under a relative humidity of 80% showed 29,026.53 mg/100 g total organic acids. For total free sugars, cold-dried sample showed the highest level at 6,560.86 mg/100 g, which decreased to 2,386.73 mg/100 g after blanching. For the ratio of essential amino acids, freeze-dried sample showed a content of 11.66%, which increased 4-fold up to 40.71~55.50% with fermentation. Both GABA and vitamin U were highest after 17 h of fermentation (110.29 mg and 6.78 mg/100 g fresh weight, respectively). A. arguta contains a variety of free amino acids that increase in amount after fermentation and thus is expected to be developed as a functional food and substitute tea.

• The Korean Journal of Food And Nutrition
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• v.17 no.3
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• pp.286-293
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• 2004

Extract of Eleutherococcus senticosus, Lycium chinensis, Angelica acutiloba and Schizandra chinensis were investigated to determine whether its addition may inflict on growth of lactic acid bacteria, freeze dry and cell viability during the storage. In cultivation with herbal extract, all strains tested did not demonstrate a significant reduction in their cell population, particularly Lactobacillus. acidophilus, L. bulgaricus, L. paracasei. But Schizandra chinensis extract inhibited growth of several strains. Immediately after freeze-drying using the skim milk 10%(w/v), sucrose 5%(w/v) with herbal extract 2.5%(v/v), the percentage viability was about 81.7%, 63.8%, 73.2%, 78.1 % in L. acidophilus, L. bulgaricus, L. paracasei, L. casei respectively. The protective effect of herbal extract to cell damage from freeze-drying was weak in comparison with control. During accelerated storage of freeze-dried lactic acid bacteria, those survival rate decrease rapidly, reaching 8 -18% in one month. But addition of Eleutherococcus senticosus extract in freeze dry of L. acidophilus showed a positive activity in storage.

• Applied Chemistry for Engineering
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• v.10 no.3
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• pp.415-418
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• 1999

The characteristics of VRLA (valve regulated Iead-acid) battery with the tubular positive plate and gel type electrolyte were examined as a function of active material filling density. The filling density of positive plate was 3.2 g/mL, 3.4 g/mL, and 3.6 g/mL, respectively. These VRLA batteries were cycled with 100% DOD (depth of discharge) at the $C_5/5$ rate, followed by IU-type recharge with $I_{max}=0.2C_{10}/10$ and a final voltage V=2.40 V/cell. The test was performed in a thermostatic room at $25{\pm}1^{\circ}C$. The result indicated that the initial capacity was independent of active material filling density, i.e., the highest initial capacity was 3.4 g/mL of filling density and the lowest was 3.6 g/mL. On aspect of the cycle-life performance of the VRLA battery, the filling density of 3.6 g/mL was similar to that of 3.4 g/mL in the positive plate, and both were higher than that of 3.2 g/mL. Water-loss and degradation of the VRLA battery were decreased according to an increase of the filling density in the positive plate. The optimum filling density of the active material was 3.4~3.6 g/mL.