• Transactions of the Korean hydrogen and new energy society
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• v.22 no.1
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• pp.60-68
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• 2011

[ $ZrO_2-TiO_2$ ]binary oxides with various Zr:Ti molar ratios were prepared by sol-gel method and Nafion$^{(R)}$/$ZrO_2-TiO_2$ composite membranes were fabricated for proton exchange membrane fuel cells (PEMFCs) at high temperature and low humidity. Water uptake, Ion exchange capacity (IEC), and proton conductivity of Nafion$^{(R)}$/$ZrO_2-TiO_2$ composite membranes were characterized and these composite membranes were tested in a single cell at $120^{\circ}C$ with various relative humidity (R.H.) conditions. The obtained results were compared with the unmodified membranes (Nafion$^{(R)}$ 112 and Recast Nafion$^{(R)}$). A Nafion$^{(R)}$/$ZrO_2-TiO_2$ composite membrane with 1:3 of Zr:Ti molar ratio showed the highest performance. The performance showed 500 mW/$cm^2$ (0.499V) at $120^{\circ}C$, 50% R. H., and 2 atm.

• Journal of Ginseng Research
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• v.16 no.2
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• pp.111-123
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• 1992

Drying characteristic data for peeled ginseng were obtained to determine dominant drying factors and fitted with five selected drying models and an empirical model. Among air temperature, relative humidity and diameter of ginseng root, drying air temperature was found to be the most influencing factor on drying rate. Drying velocity appeared faster as the drying temperature increased but its effect was less at high temperature than at low temperature. Quality change during the drying process did not occur except when relative humidity was 75fb. At high relative humidity, skin color of ginseng was turned to light brown. Approximate-Diffusion and the Empirical model for drying were in a good agreement with experimental data. The models are as follows; $.$ Approximate-Diffusion model MR = A$.$exe(-k$.$1) A = 1.72 + 0.407 In(D) - 0.0000963T3 - 0.358 In(RH) + 0.0000945 RH2 B= 1.01 + 0.0195RH - 0.O0518D2 + 0.0708 In(T) - 0.492 In(RHI-D.0000933RH2$.$Empirical model MR= Cl + Cs$.$In(t) Cl= 1.14+0.382 In(D)-0.00008477a-0.139 In(RH)+0.0000664RH2 Cs=0.440-0.0224 In(D)-0.193 In(T)+0.0000464T2-0.00000771RH2

• Journal of Korean Society of Forest Science
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• v.100 no.4
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• pp.687-692
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• 2011

Pimpinella brachycarpa, a summer-green perennial herb, is narrowly distributed in the moist forest floors. We investigated environmental characteristics and growth patterns of Pimpinella brachycarpa depending on the microenvironment in Mt. Jeombong located in the central part of Korea. P. brachycarpa populations were located at an altitude of 978~1016 m and the average atmospheric humidity hovered at 80 percent. Also, it was found that the soil moisture content was remarkably high, 26.7%, in the populations; organic matter 11.1~11.7%; the nitrate nitrogen 0.60%; available phosphorus 19.5~39.0 ppm; CEC $20.8{\sim}21.3cmolckg^{-1}$; soil pH 4.7~4.8 respectively. In case of growth pattern, the shoot length of individuals under the improved light condition in the sunny forest was statistically longer than in the dense forest. Therefore, we presumed that high humidity and ample soil moisture are abiotic factors of the growth of P. brachycarpa and that the amount of light affects the relative growth rate of individuals.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.49 no.4
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• pp.341-348
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• 2023

In this study, basic skin characteristic data was measured by measuring skin hydration, skin sebum secretion rate, skin melanin index, skin redness index, skin redness image analysis, transepidermal water loss (TEWL), and amount of stratum corneum before and after creating a temporary high temperature and low humidity environments targeting Korean women in their 20s to 50s. Stratum corneum by tape stripping was collected at each measurement and skin biomarkers including total protein content, carbonylated protein, neutral lipid, and lipid peroxidation were analyzed. Based on the results, the differences before and after creating a high temperature and low humidity environments were confirmed, the correlation between skin characteristics and skin biomarkers was confirmed, and a new skin index was created based on this. The new skin index can be used in product efficacy evaluation, and the possibility of constructing a new clinical study method and using skin biomarker discovery research through additional research was confirmed.

• Korean Journal of Microbiology
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• v.8 no.1
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• pp.21-34
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• 1970

This experiment was undertaken to examine the injurious environment conditions for occuring of the virus disease, grasserie and cytoplasmic polyhedrosis in rearing of silk worms, to observe of cytoplsamic polyhedrosis diseased silkworms with histological preparation and to define the virus origin on the gattine and the disease of shrinked form after moulting (Okichijimi). The results obtained are as follows. 1) The grasserie in spring season rearing was remarkably infected in highly percent with 20.1 % in high temperature condition during 3rd to 4th instar, the high temperature during 1st to 2nd instar and 5th instar in 16.5% and 16.3%, respectively. In the fall season rearing, the disease was infected by the feeding of soft leaves plot in 5.3% and 4.8%, respectively with significant difference in 5% level, accordingly, it was thought to the nutritional condition is a factor in occuring of the disease. 2) In spring season rearing, the number ofl infected silk worms of cytoplasmic polyhedrosis was increased in the high temperautre and high humidity conditions, and in fall season rearing, order of the low temperature and high humidity plot, first feeding plot and feeded with hard leaves plot were found insome high infected ratio of the disease than control plot. 3) The occuring of cytoplasmic polyhedrosis was observed even in control rearing plot with the examining of anatomical and histological preparation in spring and fall. 4) It was found that the high diseased ratio of the gattine and disease of shrinked form after moulting in 21.8% of control and 93.2% in feeded with inocylated plot in the biosassay of inoculum. It was defined as a virus flacherie acoording to the Danaka and Shimizu's examine method.

• Polymer(Korea)
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• v.34 no.6
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• pp.565-573
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• 2010

Copoly(2-(dimethylamino)ethyl methacrylate)(DAEMA)/butyl acrylate (BA) and copoly(methyl methacrylate)(MMA)/BA/2-(cinnamoyloxy)ethyl methacryate (CEMA), which were cross-linked with dibromoalkane and UV irradiation, respectively, were prepared for the precursors of interpenetrating polymer network (IPN) humidity-sensitive films. 3-(Triethoxysilyl)propyl cinnamate (TESPC) was used as a surface-pretreating agent for the attachment of IPN-polyelectrolyte to the electrode surface by UV irradiation. Humidity sensitive polymeric thin films with an IPN structure were prepared by crosslinking reactions of copoly(DAEMA/BA) with 1,4-dibromobutane (DBB) and copoly(MMA/BA/CEMA) by UV-irradiation. The anchoring of an IPN-polyelectrolyte into the substrate was carried out via the photochemical $[2{\pi}+2{\pi}]$ cycloaddition. The resulting humidity sensors showed a high sensitivity in the range of 20~95%RH and a small hysteresis (<1.5%RH). The response time for adsorption and desorption process at 33~94%RH was 48 and 65 s, respectively, indicating a fast response. The effects of the concentration of copolymers, molar ratio of crosslinking agents and time of the precursor solution for dip-coating on their humidity sensitive properties including water durability were investigated.

• Korean Journal of Remote Sensing
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• v.27 no.2
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• pp.163-170
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• 2011

In this paper, we analyzed the phase change of 5-triangular trihedral comer reflectors by using X-band Ground-Based Synthetic Aperture Radar (GB-SAR) system. Each reflector was set as a stationary target at a different distance from the system. We obtained total 123 full-polarization images during 40 hours continuously at 20 minute interval. Results of SAR interferometric analysis showed phase changes of maximum 2 radians and followed similar pattern with atmospheric data. Through a GB-SAR phase formula that includes refractive index in the air, we performed regression analysis for refractive index as a function of atmospheric humidity, temperature and pressure. As a result, refractive index of air in X-band showed relatively high coefficient of determination with humidity and temperature (0.72 and 0.76 on average, respectively) but not so with pressure (0.34). The refractive index of air in X -band changed by 3.14\;{\times}\;10^{-5}$ during the measuring time with a humidity range of 50% ~ 90% and a temperature range of $-1^{\circ}C$ ~ $9^{\circ}C$. We expect that a total expression of refractive index of air including humidity, temperature and pressure can be calculated when more extensive data would be collected at various atmospheric conditions.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.19 no.6
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• pp.87-100
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• 2016

This research was performed for the purpose of providing useful and base data and preservation strategy of growth characteristics of Rhododendron micranthum. From the result of research, wild growth area of Rhododendron micranthum was discovered near steep forest road on 695~901m in altitude above sea level of Baekdu-daegan National Arboretum. Vegetation colony structure of Site I was resulted in Pinus densiflora(tree stratum M.I.P.=45.3%) is dominants, Betula schmidtii(arborescent M.I.P.=9.8%) is second dominant, and Site III resulted in Pinus densiflora(tree stratum M.I.P.=30.5%) is dominants, Betula schmidtii(arborescent M.I.P.=10.3%) is second dominant. Site II resulted in Betula schmidtii(arborescent M.I.P.=30.4%) is dominants and Pinus densiflora tree(tree stratum M.I.P.=8.3%) is second dominants. For herbs, it was researched that the rate of one year herb of chrysanthemum family(10), rice family(3), sedge(2) was higher than near forest area. Among Species diversity index, that of Shannon was in range of 0.7348~1.1090. After comparing this with similar area, this value was relatively low. Dominance analysis result was analyzed that various groups are evenly distributed. Monthly highest average temperature is $23.9^{\circ}$ in Site A and Site B, and monthly lowest average temperature is $-4.5^{\circ}C$ in Site I and $-4.7^{\circ}C$ in Site II. Monthly maximum average humidity is 85.6% in Site I and 83.2% in Site II. Monthly minimum average humidity is 60.9% in Site I and 60.8% in Site II and it showed that these 2 area are located far away but have similar temperature and humidity characteristic and climate environment is similar. It was analyzed that humidity is high with the result of annual average humidity is over 60%. In growth characteristic, it showed that doubt damage of Stephanitis pyrioides, exposure of roots, peeled bark was discovered and supplement on this is urgent.

• Conservation Science in Museum
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• v.2
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• pp.19-25
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• 2000

In order to studies proper conservation treatment condition of waterlogged archaeological wood excavated from wetland in Shinchang-dong, Kwangju, 2 kinds of wooden objects were treated with PEG(Poly-Ethylene Glycol), sucrose and lactitol and their size stability and relative humidity were analyzed and compared each other. The result showed that Quercus spp. had the highest size stability in 2 Step-PEG treatment using PEG#200(MW:200) and PEG#4000 (MW:3,350) and Acer spp. was the highest in treatment using only PEG#4000. In relative humidity test after treatment 2 Step-PEG treatment showed the lowest size stability. In the meantime, sucrose and lactitol-treated sample was fast for penetration, sucrose-treated sample showed a sharp increase for penetration in as high as 84% humidity condition and medicine flew out a lot and lactitol-treated sample got enlarged with fine cracking(splitting) in relative humidity test. In relative humidity test, the samples showed cracking(splitting) in all treatment materials except for 2 Step-PEG treatment. This study showed that waterlogged archaeological wood excavated from Shinchang-dong had the highest size stability and highest adaptation to humidity change in case of treatment with 2 Step-PEG.

• Journal of Energy Engineering
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• v.25 no.3
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• pp.27-33
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• 2016

The heat recovery system that was applied in this study, is the energy-saving type that can produce the maximum cooling capacity less power in use. In order to have a more precise control function the temperature and humidity of the constant temperature and humidity machine, control algorithm is applied to designed a fuzzy PID controller, and the outside air compensation device (air-cooled) demonstrated excellent ability to dehumidify the moisture, $-20^{\circ}C$ in winter. High efficiency and the low-noise type sirocco fan operate quitely and designed to fit the bottom-up and top-down in accordance with the characteristics of equipment. as a result of experiment data, the conversion efficiency is 95% or more, power recovery time is within 5sec, stop delay time is within 30sec, pump down time is 10sec, pump delay time is 5sec, heating delay time is 5sec, temperature deviation is ${\pm}2^{\circ}C$ (cooling deviation: $2^{\circ}C$, Heating deviation : $2^{\circ}C$), humidity deviation is a ${\pm}5%$ (humidification deviation 3.0%, dehumidification deviation 3.0%). Recently, ubiquitous technology is important. so, the constant temperature and humidity machine designed to be able to remotely control to via the mobile phone, and more scalable to support MMI software and automatic interface. Further, the life of the parts and equipment is extended by the failure.