• 한국농공학회지
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• 제33권2호
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• pp.112-119
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• 1991

Some experiments were carried out to investigate the effects of freezing and thawing on the strength and strain characteristics of alluvial silty clay under the different temperatures, loading and moisture conditions. The results were as follows; 1. The soil used was proved to be consisted of silty clay with honey-combed structure, and showed higher dilatancy, frost activity and lower stability in natural state. 2. Soil treated with freezing and thawing cycles showed lower compressive strength compared with the non treated, The strength decreased with incement of freezing and thawing cycles. It's shapes of stress-strain curves were flat and did not formulate a peak while the peak strength of higher moisture content soil decreased with the increment of moisture content. It's decrement ratio was most distinctly shown at the first one cycle of freezing and thawing. 3. The cohesion decreased due to freezing and thawing cycles but internal frcition angle was not changed. 4. The liquid limit decreased with increment of freezing and thawing cycles, and became almost constant after three cycles of freezing and thawing. 5. The strength under simple loading at failure mode was appeared to be higher compared with the cyclic loading after freezing and thawing but initial moisture content effect was not observed. 6. Ice lense was not observed within 50% of ice content ratio but observed over 100%. The higher the ice content ratio, the higher the peak strength. As a matter of fact, it seems that an optimum ice content ratio exists for plastic mode and the least compressive strength.

• Journal of the Korean Wood Science and Technology
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• 제37권6호
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• pp.497-504
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• 2009

본 연구에서는 국산 잣나무, 일본잎갈나무, 신갈나무 및 산벚나무 Polyethylene glycol (PEG) 처리재의 초기 흡, 탈착과정에서 중량, 함수율 및 치수변화의 특성을 검토하였다. 각 수종의 무처리재와 PEG 1000, 2000, 4000 처리재는 상대습도 20%, 65% 및 98% 조건에서 1주일 동안 조습시켰다. 그 결과, 초기 흡, 탈착과정에서 PEG 1000과 2000으로 처리한 잣나무, 일본잎갈나무 및 산벚나무재의 중량은 크게 증감하였지만, 신갈나무재는 거의 변화가 없었다. PEG처리에 의한 함수율은 신갈나무재를 제외한 3 수종에서 상대습도의 변화에 의해 다소 높게 나타났으나, 모든 수종에서 PEG처리에 의해 치수변화를 예방할 수 있었다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.1034-1037
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• 2006

We have developed a novel thin film encapsulation method for thin-cathode OLED by introducing organic (not polymer)/inorganic multiple thin films to protect device, which is shown to slow down the permeation rate of moisture and oxygen. From the stability test of devices, the projected lifetime of thin-cathode OLED device with thin film encapsulation was similarly to that with glass lid encapsulation.

• 한국염색가공학회지
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• 제10권4호
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• pp.30-36
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• 1998

The need for the effective flame retardant finishing for synthetic fiber Is required. This paper is focussed on the analysis of physical properties of nylon 6 fabric treated with tris(2-chloroethyl) phosphate(TCEP) in comparision with the untreated fabric. In order to evaluate the flame retardance effect, limiting oxygen index and burn rate were determined. Above 20% add-on of TCEP on nylon 6 fabric, reasonable flame retardancy was observed. Thermal stability of the treated nylon 6 fabric was evaluated by TGA. It seems that TCEP acts via a condensed phase mechanism. Tenacity and moisture regain of the treated fabrics were not changed and washfastness of those was excellent.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1998년도 가을 학술발표회논문집
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• pp.207-210
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• 1998

Among the common textile fibers, wool has excellent wrinkle recovery. However, absorbed moisture plasticizes the structure and increases the rate of stress relaxation during wear deformation. Therefore, the wrinkle recovery of wool deteriorates under very high-humidity conditions and is of particular concern in men's lightweight suits, where the trend is toward wool fabrics of lightweight and bright color in which the wrinkles are emphasized. (omitted)

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.262-264
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• 2009

Ternary oxides with controlled band gap energy and reduced reactivity against moisture and carbon dioxide gas were designed and studied as a potential material for protective layer of ac-PDPs. The results showed a significant reduction in firing voltage and improved environmental stability.

• 한국가구학회지
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• 제20권6호
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• pp.560-565
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• 2009

It is known that heat treatment decreases the hygroscopicity of wood. Thus heat-treated wood is good for outdoor construction due to its improved dimensional stability. This study is to investigate the hygroscopicity and discoloration of spruce and birch boards heat-treated above $190^{\circ}C$. The equilibrium moisture contents (EMCs) at all relative humidities decreased with the increase of heat treatment temperature and/or time for both spruce and birch. It was revealed that heat-treatment temperature affected more on the hygroscopicity thaan heat-treatment time. The average basic densities decreased for the spruce specimens, but increased for the birch specimens with an increase of the treatment time and/or temperature. The same heat treatment condition (190-8) made the birch specimens darker than the spruce specimens.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2003년도 추계학술발표대회 논문집
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• pp.7-10
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• 2003

Blue-light-emitting peiymer/dielectric nanolayer nanocomposites were prepared by the solution intercalation method and employed in electroluminescent device. Their photoluminescence and electroluminescence characteristics suggested that the nanolayers isolate the polymer chains and hinder the formation of excimers and aggregates. By reducing the excimer formation and its deleterious effects on emission efficiency, both the color purity and the luminescence stability were improved. Furthermore, the dielectric nanolayers have an aspect ratio of about 500 and therefore act as efficient barriers to oxygen and moisture diffusion, which produced a dramatic increase in the device stability.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 봄 학술발표회 논문집
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• pp.217-222
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• 2000

A large Pc structure building is system that consisted of bearing wall and slab joint. It has general structure stability from unity thar each members tied at joint. The strength of mortar that packing in joint among panels is important to internal force in entire building system. Do, if we could get early strength estimation with microwave. It would bring good construction planning, reduce construction time, and judge building stability and so on. The purpose of this study is to develop early estimation method for making better quality control and constructing good PC panel structure. The results of this study were as follows :1) With sealed molds, reduced moisture volatilization to more than 60% and enlarged 30% accelerated compressive strength than before one. 2) To get more accelerated strength, we should control maximum temperature difference to $30^{\circ}C$ downward 3)Interrelation with 7-day and 28-day strength were 0.831,0.902, and it is above than before one

• Food Science and Biotechnology
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• 제18권1호
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• pp.185-189
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• 2009

Microencapsulation of flavor was carried out by molecular inclusion process using $\beta$-cyclodextrin (${\beta}CD$). ${\beta}CD$-flavor complex was prepared at various flavor-to-${\beta}CD$ ratios (1:6-1:12) to determine the effect of ${\beta}CD$ concentration on the inclusion efficiency. Maximum total oil retention and minimal surface oil content were obtained at flavors to ${\beta}CD$ ratio of 1:10. The physical properties and controlled release pattern of flavors from ${\beta}CD$-flavor complex were measured and compared with spray-dried microcapsules prepared using carbohydrate wall system. ${\beta}CD$-flavor complex showed higher total oil retention and surface oil contents, smaller mean particle size, lower moisture uptake, and higher oxidation stability than spray-dried microcapsule. Oxidative stability of flavor was correlated with hygroscopicity of wall materials. The controlled release mechanism was highly affected by temperature and characteristics of wall materials.