• 한국재료학회:학술대회논문집
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• 한국재료학회 2002년도 추계학술발표강연 및 논문개요집
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• pp.179-179
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• 2002

• 한국식품저장유통학회지
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• 제23권3호
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• pp.369-377
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• 2016

본 연구는 과열증기처리 기술을 양파에 적용하여 불쾌취를 저감화하고, 이를 통해 고품질 양파 가공품 개발 및 소재화에 활용하기 위한 기초 자료를 확보하고자 과열증기처리에 따른 양파의 휘발성 물질, 불쾌취 유발 물질과 항산화활성, 조직감, 관능적 특성 등 품질특성을 분석하였다. 과열증기처리에 의해 휘발성 향기성분 및 불쾌취와 매운맛의 지표 물질이 저감화됨을 확인하였다. 항산화활성 및 총 페놀성 화합물 함량은 다소 증가하는 경향을 보였으며, hardness, chewiness 등은 확연하게 감소하는 것으로 나타났다. 양파 추출액의 총 가용성 고형분 함량은 처리에 의해 전체적으로 증가하였으며 처리에 따라 기호도 점수가 높아지는 것을 확인하였다. 결과적으로 과열증기 처리가 양파의 불쾌취저감화에 효과적임을 확인할 수 있었다. 본 연구결과는 과열증기 기술을 적용한 양파의 불쾌취 저감화 및 이를 통한 다양한 고품질 가공품 개발 및 소재화를 위한 중요한 기초 자료로 활용될 수 있으리라 판단되며, 과열증기오븐 처리를 통해 불쾌취를 조절함과 동시에 생리활성능을 지니는 향기 성분 및 유용성분의 감소는 최소화하는 추가적인 연구가 필요할 것으로 사료된다.

• 한국세라믹학회지
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• 제43권7호
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• pp.427-432
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• 2006

The preparation of SiC powder by SHS in the system of $SiO_2-Mg-C$ was investigated in this study. The effects of various processing parameters such as the initial pressure of inert gas in reactor, the content of Mg and C in mixture and the size of $SiO_2$ particles on the synthesis of SiC by SHS methode were investigated. The minimum initial pressure of inert gas in reactor for SHS reaction in this system was 5 atm, and as the pressure increased, and the concentration of unreacted Mg decreased. At 50 atm of the initial inert gas pressure in reactor, the optimum composition for the preparation of pure SiC was $SiO_2+2.5Mg+1.2C$. SiC powder synthesized in this condition had a mixture of ${\alpha}-SiC\;and\;{\beta}-SiC$ with an irregular shape and the particle size of $0.5{\sim}0.8{\mu}m$.

• Steel and Composite Structures
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• 제23권1호
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• pp.87-94
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• 2017

Steel structures often require strengthening due to the increasing life loads, or repair caused by corrosion or fatigue cracking. Carbon Fiber Reinforced Polymers (CFRP) is one of the materials used to strengthen steel structures. Most studies on strengthening steel structures have been carried out on steel beams and steel columns under centric compression load. No independent article, to the author's knowledge, has studied the effect of CFRP strengthening on steel columns under eccentric compression load, and it seems that there is a lack of understanding on behavior of CFRP strengthening on steel columns under eccentric compression load. However, this study explored the use of adhesively bonded CFRP flexible sheets on retrofitting square hollow section (SHS) steel columns under the eccentric compression load, using numerical investigations. Finite Element Method (FEM) was employed for modeling. To determine ultimate load of SHS steel columns, eight specimens with two types of section (Type A and B), strengthened using CFRP sheets, were analyzed under different coverage lengths, the number of layers, and the location of CFRP composites. Two specimens were analyzed without strengthening (control) to determine the increasing rate of the ultimate load in strengthened steel columns. ANSYS was used to analyze the SHS steel columns. The results showed that the CFRP composite had no similar effect on the slender and stocky SHS steel columns. The results also showed that the coverage length, the number of layers, and the location of CFRP composites were effective in increasing the ultimate load of the SHS steel columns.

• 한국식품위생안전성학회지
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• 제14권1호
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• pp.76-83
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• 1999

Solid phase microextraction (SPME) was used for the determination of 6 standard solvents (methanol, isopropanol, methyl ethyl ketone, ethyl acetate, cyclohexane, toluene) in food packaging materials. SPME method is a solvent-free sample preparation technique in which a fused silica fiber coated with polymeric organic liquid is introduced into the headspace above the sample. SPME method using fiber coated polydimethylisiloxane (PDMS) was compared with static headspace (SHS) method used as a reference. It was found that the optimal adsorption condition using PDMS-SPME method was 2$0^{\circ}C$ for 15 minutes for the standard solvents. Detection limits, linearity, reproducibility and recovery of both SHS and PDMS-SPME methods have been determined using 6 standard solvents. Both methods were characterized by high reproducibility and good linearity. Using SHS methods, the mean recovery of the 6 standard solvents was ranged from 75.5% to 105.8% with a mean relative standard deviation (RSD) of 0.3% to 4.8%. With PDMS-SPME method, the mean recovery of the 6 standard solvents was ranged from 86.7% to 108.3% with a mean RSD of 0.4% to 2.5%. The detection limits of both methods were the same for toluene, cyclohexane and methyl ethyl ketone; those of PDMS-SPME method were higher than those of SHS method for methanol, isopropanol and ethyl acetate. PDMS-SPME fiber shoed excellent adsorption for non-polar solvents such as toluene, while it showed relatively low adsorption for polar solvents such as methanol.

• 한국재료학회지
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• 제12권9호
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• pp.696-700
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• 2002

The Ti-aluminide intermetallic compound was formed from high purity elemental Ti and Al foils by self-propagating, high-temperature synthesis(SHS) in hot press. formation of $TiAl_3$ at the interface between Ti and Al foils was controlled by temperature, pressure, heating rate, and so on. According to the thermal analysis, it is known in this study that the heating rate is the most important factor to form the intermetallic compound by this SHS reaction. The V layer addition between Al and Ti foils increased SHS reaction temperatures. The fully dense, well-boned inter-metallic composite($TiA1/Ti_3$Al) sheets of 700 m thickness were formed by heat treatment at $1000^{\circ}C$ for 10 hours after the SHS reaction of alternatively layered 10 Ti and 9 Al foils with the V coating layer. The phases and microstructures of intermetallic composite sheets were confirmed by EPMA and XRD.

• 우울조울병
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• 제10권1호
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• pp.31-36
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• 2012

Objectives : The aim of this study was to investigate the relationship between depressive symptom, spiritual well-being and state hope in early adults and middle aged patients with depression. Methods : A total of 180 outpatient were surveyed with Beck Depression Inventory (BDI), Functional Assessment of Chronic Illness Therapy-Spiritual Well-being Scale (FACIT-Sp) and The State Hope Scale (SHS). Mean scores of BDI, FACIT-Sp and SHS were compared between two groups of different age. Correlation analysis and multiple linear regression analyses were performed to identify the effect of BDI and FACIT on SHS according to age. Results : Mean scores of SHS and FACIT were higher significantly in middle aged group than early adults group, while BDI was not different between two groups. And early adults and middle aged patient's state hope showed a significantly negative correlation with spiritual well-being. In regression analysis, the effect of BDI, FACIT on SHS were significant in both groups and the regression model explained 42% of the variance of state hope in early adults group and 26% in middle aged group, respectively. Conclusion : These findings suggest that in depressive symptom and low state hope relationship, spirituality is important protective factor in both aged adult outpatients with depression.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2007년도 추계학술대회 및 제23회 정기총회
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• pp.290-292
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• 2007

최근 우리나라 여러 주요 항만에 해상교량의 건설이 진행 중이거나 계획 중에 있는데, 이들 교량의 설치 위치나 규모가 주로 경제적인 측면만을 강조하여 이루어짐으로써, 선박 통항안전에 위협을 주고 있으며, 이해 당사자 간의 갈등이 고조되고 있는 현실이다. 따라서 이 연구에서는 국내에서 해상교량 건설시 사전에 수행되어지는 SHS(Ship Handling Simulation)에 관한 수행기관별 평가기법에 대하여 조사하고 분석한다.

• 한국세라믹학회지
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• 제33권11호
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• pp.1237-1244
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• 1996

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2002년도 춘계학술발표대회 논문집
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• pp.155-158
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• 2002

Fabrication process of metal/intermetallic laminated composites by using self-propagating high temperature synthesis(SHS) reactions between Ni and Al elemental metal foils have been investigated. Al foils were sandwiched between Ni foils and heated in a vacuum hot press to the melting point of aluminium. SHS reaction kinetics was thermodynamically analyzed through the final volume fraction of the unreacted Al related with the initial thickness ratio of Ni:Al and diffusion bonding stage before SHS reaction. Thermal aging of laminated composites resulted in the formation of functionally gradient series of intermetallic phases. Microstructure showed that the main phases of intermetallics were NiAl and $Ni_3Al$ having higher strength at room and high temperatures. The volume fractions of intermetallic phases were measured as 82.4, 58.6, 38.4% in 1:1, 2:1, 4:1 initial thickness ratio of Ni:Al.