• Journal of Biosystems Engineering
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• 제34권1호
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• pp.15-20
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• 2009

This study was conducted to develop a moisture sensor for rapeseed, a bio-diesel material. A typical rapeseed, SUNMANG, was used as a raw material. The rapeseed moisture content sensor consists of three components, such as upper and bottom electrodes, a test material dish, and a fixing housing. To evaluate the performance, a data acquisition system was equipped with the rapeseed moisture sensor, computer, printer, and main board. The findings of this study were: 1) the rapeseed moisture content was inversely proportional to electric resistance, and 2) values of electric resistance were recorded in a range of $10{\sim}100\;M{\Omega}$, depending upon a change of the moisture content. The determination of coefficient ($R^2$) and standard error between rapeseed moisture content and electric resistance were 0.9921 and ${\pm}0.289$, which indicated a highly correlative relationship. The response of rapeseed moisture sensor to temperature change was also observed for further performance test. Satisfying results were obtained, such as the determination of coefficient ($R^2$) of 0.9918, predicted standard error of ${\pm}0.373%$, deviation of 0.103%, measurement error of $0.14{\sim}0.48%$, standard deviation of $0.01{\sim}0.22%$, and measurement time of 28.3 s per point, respectively.

• Journal of the Korean Wood Science and Technology
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• 제12권1호
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• pp.31-37
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• 1984

For the modification of kiln drying schedule, relations between resistance to drying Rd and the moisture content or drying times were found for 4/4, 6/4 and 8/4 green Douglas fir heartwood by the mild drying schedule and the severe drying schedule until the average moisture content was about 10 percent. The results of this study were as follows. 1. Resistance to drying of thicker lumber was higher than that of thinner lumber and resistance to drying of three different thicknesses were negligible between the mild-and the severe drying schedule. The relationships between resistance to drying and two schedules or three thicknesses of lumber were $Rd_1=1.830{\times}10^5\;M^{-2.24}$ for 4/4 lumber by the mild drying schedule, $Rd_2=1.822{\times}10^5\;M^{-2.25}$ for 4/4 lumber by the severe drying schedule, $Rd_3=2.352{\times}10^5\;M^{-2.14}$ for 6/4 lumber by the mild drying schedule, $Rd_4=3.457{\times}10^5\;M^{-2.27}$ for 6/4 lumber by the severe drying schedule, $Rd_5=1.317{\times}10^6\;M^{-2.56}$ for 8/4 lumber by the mild drying schedule, $Rd_6=8.267{\times}10^5\;M^{-2.40}$ for 8/4 lumber by the severe drying schedule. 2. Thinner lumber exhibited lower level of moisture content and shorter drying time required at intersection point between the moisture content and resistance to drying as a function of drying time than those of thicker lumber. Drying time of mild drying was longer than that of severe drying and similar to the level of moisture content at intersection point.

• 한국도로학회논문집
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• 제9권4호
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• pp.149-158
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• 2007

본 연구는 산업부산물인 폐타이어인 #30 체를 거의 다 통과한 CRM 입자를 아스팔트 콘크리트 혼합물의 개질재로서 8%, 10%, 12%를 각각 습식 및 건식방법의 CRM 개질아스팔트 혼합물에 대하여 동결융해에 의한 수분취약성 시험을 통하여 동결융해저항성을 평가하였다. 건식 및 습식방법에 의한 CRM 개질아스팔트 혼합물의 배합설계를 통하여 최적아스팔트 함량을 결정하였고. OAC로 제조한 CRM 개질 혼합물은 반복주행시험과 수분취약성시험을 수행하였다. 그 결과, CRM 개질아스팔트 혼합물의 소성변형 저항성은 일반 AP-5 혼합물보다 우수하게 나타났다. 그러나 수분취약성시험에 의한 동결융해 저항성이 상당히 낮게 나타나 동결융해에 의한 수분취약성에 아주 민감한 것으로 나타났다. 반면에, CRM 개질아스팔트 혼합물에 박리저감제의 첨가는 동결융해에 의한 수분취약성에 대한 저항성을 상당히 향상시키는 것으로 나타났다. 따라서 국내에서 CRM 개질아스팔트 혼합물을 사용할 때에는 반드시 수분취약성에 대한 동결융해저항성에 대한 예방책이 제시된 혼합물을 사용될 것이 권장된다.

• 한국염색가공학회지
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• 제26권4호
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• pp.322-330
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• 2014

The phospholipid-based MPCE(2-Methacryloxyethyl Phosphoryl Chlorine) copolymer was mixed with wet polyurethane for coating of nylon fabrics. The substitution rate of water in coagulation bath with DMF was changed under control of the size of formed hydrophilic microporous cell enable to manufacture excellent breathable, anti-bacterial and moisture control fabrics. Biocompatible property, vapor permeability, hydrostatic pressure, moisture management and anti-bacterial property were investigated for treated nylon fabrics. In result, increased moisture transmission rates, decreased water resistance and outstanding moisture control property could be confirmed by enhanced hydrophilicity of wet-coated nylon fabric with MPCE copolymer.

• Journal of the Korean Wood Science and Technology
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• 제20권3호
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• pp.21-27
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• 1992

The amount of moisture transmitted under four different humidity conditions was measured in earlywood and latewood for Cryptomeria japonica(LT specimens). The results obtained are summarized as follows. The vapor permeability in eariywood was about three times larger than that of latewood. The vapor permeabilities in earlywood and late wood depended on the average moisture content of the wood. This indicates that moisture transmission is influenced by vapor permeability or vapor-transmission resistance, but the values obtained by experiments do not have great adaptability for practical situations because of changes in the experimental conditions. There fore, it is necessary to know the moisture content along the flow direction in order to explain the moisture transmission of wood. The vapor permeability was calculated using the density in air dried wood. These were then compared with the experimental values. The vapor permeabilities calculated with this density in the radial direction(LR specimen) had a good tendency to agree with the experimental values, but not so in tangential direction(LT specimen).

• 한국도로학회논문집
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• 제10권4호
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• pp.41-52
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• 2008

본 연구는 박리방지 첨가제를 혼입한 아스팔트 혼합물의 수분민감성에 대한 특성 평가 방안을 제시하고자, 기존의 수침 시험을 개선한 3가지 종류($H_c$, $V_s$, F-T)의 수침 방법을 통하여 생석회, 소석회, 1종의 액상 박리방지 첨가제를 혼입한 각 아스팔트 혼합물에 대한 수분민감성의 거동 특성을 분석하였다. 실험방법은 AASHTO TP-9에 규정된 간접인장시험(Indirect Tensile Test, IDT)을 통한 크리프시험 (Creep Test), 회복탄성계수시험(Resilient Modulus Test) 및 강도시험(Strength Test)을 수행하였다. 분석방법으로는 미국 플로리다 대학의 Roque에 의해 제안된 에너지비(Energy Ratio, ER) 개념을 사용하여 박리방지제의 사용에 따른 효과 및 수분민감도 특성을 평가하였다(Roque, 2004). 시험결과, 수분처리 방법 에 따른 아스팔트 흔합물의 물성 변화뿐만 아니라 박리 방지 첨가제에 따른 물성 변화가 현저하게 나타났다. 또한 누적 수분 손상에 의해 발생되는 균열에 대한 저항성이 각 첨가제 및 수분처리 방법에 따라 변화됨을 나타내었다. 이를 토대로 Energy Ratio를 분석한 결과 약 $10{\sim}30%$ 정도의 균열 저항성 변화가 나타났다.

• 한국표면공학회지
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• 제50권6호
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• pp.486-491
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• 2017

Silver nanowire (AgNW) transparent electrode is one of next generations of flexible and transparent electrode. The electrode shows high conductivity and high transparency comparable to ITO. However, the electrode is weak against heat. The wires are separated into nanodots at temperature above $200^{\circ}C$. It causes the electrical resistance increase. Moreover, it is vulnerable to oxygen and moisture in the atmosphere. The improvement of thermal and moisture resistance of silver nanowire transparent electrode is the most important for commercializing. We proposed silver nanowires transparent electrode which is capped with very thin nickel oxide layer. The nickel oxide layer is five nanometers of thickness, but the heat and moisture resistance of the transparent electrode is effectively improved. The AgNW/NiO electrode can endure at $300^{\circ}C$ of temperature for 30 minutes, and resistance is not increased for 180 hours at $85^{\circ}C$ of temperature and 85% of relative humidity. We showed an applications of transparent and flexible heater using the electrode, the heater is operated more than $180^{\circ}C$ of temperature.

• 한국염색가공학회지
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• 제21권1호
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• pp.38-45
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• 2009

First of all, the properties imparted to PET fabrics are resistance to and recovery from creasing or wrinkling when wet or dry; high resistance to stretch in the filament yarns but not in the staple; high abrasion resistance; good texture and appearance; resistance to heat ageing; good chemical resistance and good resistance, behind glass, to sunlight. But, the low moisture regain of PET fabric conduces to static troubles in textile processing. Furthermore, garments made from PET may, during wear, develop electric charges which attract to the fabric particles of soil(dirt, swarf, dust) flying in the air, so that the cuffs of shirts, for example, become soiled quickly and are not easily laundered clean. The sericin constitutes 25$\sim$30％ of silk protein and surrounds the fibroin fiber with sticky layer that supports the formation of a cocoon. The useful biochemical properties of sericin protein are oxidation resistant, antibacterial, UV resistant, hydrophilic property, and good affinity with hydrophobic material. These properties can be used as an improving reagent or a coating agent for natural and synthetic fibers, fabrics, and other intermediate products. The sericin is also applied to cross-link, and can be blended with other materials. In this study, we modified the surface of PET fabric by mixture of sericin finishing agent; sericin, polyuretane binder and 1,2,3,4-butanetetracarboxylic acid (BTCA) cross-link agent. Also, we investigated the finshing effect; moisture regain, stiffness, handle, drape and electrostatic. The moisture regain of PET fabric treated with sericin finishing agent was higher than that of untreated PET fabric. As a result of evaluating influence about handle of PET fabrics treated with sericin finishing agent, it was confirmed that the sericin finishing agent could be use as a linen like finishing agent.

• 한국조경학회지
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• 제35권3호
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• pp.105-113
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• 2007

This study was conducted to analyze the effects of environmental factors such as soil moisture, light intensity, temperature and humidity on changes in cambial electrical resistance. To improve data quality, cambial electrical resistance was continuously measured at fixed points by using a data logger isolated from alternating current. The relationship between environmental factors and changes in cambial electrical resistance was also analyzed. The results are as follows: 1. Cambial electrical resistance is highly correlated to the temperature of the measured area(r=-0.934). Therefore, temperature compensation is needed to analyze the effects of other environmental factors on cambial electrical resistance changes. 2. If temperature is compensated for, the change of cambial electrical resistance is highly correlated to water vapor pressure(r=-0.836). 3. If temperature and humidity are compensated for, the change of cambial electrical resistance is highly correlated to intensity of light(r=-0.738). 4. Diurnal deviation of soil water potential is not more significantly related than the change of cambial electrical resistance. However, in the long-term, soil water potential and cambial electrical resistance are highly correlated(r=-0.831). This indicates that soil moisture significantly influences the long-term change of cambial electrical resistance.

• Restorative Dentistry and Endodontics
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• 제45권2호
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• pp.24.1-24.9
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• 2020

Objectives: It is known that bioactive materials interact with the dentin to undergo biomineralization. The exact role of moisture in this interaction is unknown. Here, we investigate the effects of dentin moisture conditions on the dislocation resistance of two bioactive root canal sealers (MTA Fillapex [Angelus Solucoes Odontologicas] and GuttaFlow BioSeal [Colténe/Whaledent AG]) at 3 weeks and 3 months after obturation. Materials and Methods: Mandibular premolars (n = 120) were prepared and randomly divided into 3 groups based on the dentin condition: group 1, dry dentin; group 2, moist dentin; group 3, wet dentin. Each group was divided into 2 subgroups for root canal filling: MTA Fillapex and GuttaFlow BioSeal. Dislocation resistance was evaluated by measuring the push-out bond strength at 3 weeks and 3 months. Failure modes were examined under a stereomicroscope. Data were statistically analyzed by Kruskal-Wallis test with a significance level of 5%. Results: Moist dentin resulted in higher bond strength values for both materials at both time points. This was significantly higher than wet and dry dentin for both the sealers at the 3 months (p < 0.05), while at 3 weeks it was significant only for GuttaFlow Bioseal. The different moisture conditions demonstrated similar trends in their effects on the dislocation resistance of the 2 root canal sealers. Conclusions: The dentin moisture conditions had a significant impact on its interaction with the bioactive materials tested. Maintaining moist dentin, but not dry or wet dentin, may be advantageous before the filling root canals with bioactive sealers.