• Journal of Ginseng Research
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• v.4 no.1
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• pp.104-120
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• 1980

The effects of temperature on transpiration, chlorophyll content, frequency and aperture of stomata, and leaf temperature of Panax ginseng were reviewed. Temperature changes of soil and air under spade roof were also reviewed. Growth responses of responses of ginseng plant at various temperature were assessed in relation to suseptibillity of ginseng plants. Reasonable management of ginseng fields was suggested based on the response of ginseng to various temperatures. Stomata frequency may be increased under high temperature during leaf$.$growing stage. Stomata aperture increased by high temperature but the increase of both frequency and aperture appears not enough for transpiration to overcome high temperature encountered during summer in most fields. Serial high temperature disorder, i.e high leaf temperature, chlorophyll loss, inhibition of photosynthesis, increased respiration and wilting might be alleviated by high humidity and abundant water supply to leaf. High air temperature which limits light transmission rate inside the shade roof, induces high soil temperature(optimum soil temperature 16∼18$^{\circ}C$) and both(especially the latter) are the principal factors to increase alternaria blight, anthracnose, early leaf fall, root rot and high missing rate of plant resulting in poor yield. High temperature disorder was lessen by abundant soil water(optimum 17∼21%) and could be decreased by lowering the content of availability of phosphorus and nitrogen in soil consequently resulting in less activity of microorganisms. Repeated plowing of fields during preparation seems to be effective for sterilization of pathogenic microoganisms by high soil temperature only on surface of soils. Low temperature damage appeared at thowing of soils and emergence stage of ginseng but reports were limited. Most limiting factor of yield appeared as physiological disorder and high pathogen activity due to high temperature during summer(about three months).

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.4 no.4
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• pp.263-276
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• 1992

The transmission current in a power cable is determined under the condition of separate pipe cooling. To this end, the thermal analysis is conducted with the standard condition of separate pipe cooling system, which constitutes one of the underground power transmission system. The changes of transmission current in a power cable with respect to the variation of temperatures and flow rates of inlet cooling water as well as the cooling spans are also determined. As a consequnce, the corresponding transmission current is shown to vary within allowable limit, resulting in the linear variation of the current for most of the cable routes. The abrupt changes of current, however, for the given flow rate of inlet cooling water in some cooling span lead to the adverse effects on the smooth current transmission within the underground power transmission system. In practice, it is expected that the desinging of the separate pipe cooling system in conjunction with the evaluation of system capacity should take into account the effects of design condition on the inlet cooling flow rate.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.26 no.11
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• pp.1630-1637
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• 2002

A slab-wick heat pipe was fabricated and tested for applications where the condenser temperature is in a range of 80 to 12$0^{\circ}C$. The pipe material was 9.53 mm O.D. copper tube and the working fluids were ethanol and water. The total length of the heat pipe was 1.6 m, in which evaporator section was 1.4 m and the condenser was 0.10 m. The slab was a composite wick structure fabricated with STS316 wire screens. Thermal load was varied for a specified fill charge ratio and inclined angle. The optimum fill charge ratio was identified to be 110% based on a theoretical calculation of the pore space in the slab wick of the heat pipe. The maximum thermal load was 120W for ethanol and the same was 200W for water with the condenser temperature of 8$0^{\circ}C$. The thermal performance of the slab wick heat pipe is analysed in terms of temperature characteristics and thermal resistance against thermal load, tilt angle and fill charge ratio.

• Journal of Korean Society of Water and Wastewater
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• v.29 no.1
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• pp.57-63
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• 2015

Recently, Korea's municipal wastewater treatment plants generated amount of wastewater sludge per day. However, ocean dumping of sewage sludge has been prohibited since 2012 by the London dumping convention and protocol and thus removal or treatment of wastewater sludge from field sites is an important issue on the ground site. The hydrothermal carbonization is one of attractive thermo-chemical method to upgrade sewage sludge to produce solid fuel with benefit method from the use of no chemical catalytic. Hydrothermal carbonization improved that the upgrading fuel properties and increased materials and energy recovery, which is conducted at temperatures ranging from 200 to $350^{\circ}C$ with a reaction time of 30 min. Hydrothermal carbonization increased the heating value though the increase of the carbon and fixed carbon content of solid fuel due to dehydration and decarboxylation reaction. Therefore, after the hydrothermal carbonization, the H/C and O/C ratios decreased because of the chemical conversion. Energy retention efficiency suggest that the optimum temperature of hydrothermal carbonization to produce more energy-rich solid fuel is approximately $200^{\circ}C$.

• Journal of Pharmaceutical Investigation
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• v.17 no.1
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• pp.38-40
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• 1987

To optimize the preparation condition of oil in water microemulsion rheological method was used. The viscosity-temperature curve of refined soybean oil was recorded and from this result microemulsion was prepared at various temperatures and evaluated by Coulter counter during 3 weeks. The difference in rheograms of crude emulsion and the microemulsion varying the number of passes in the homogenizer was also examined. From above experiments following conclusions were obtained. 1) Through all the process, temperature was an important factor and the optimum was $60-80^{\circ}C$. 2) By first pass in the homogenizer, most oil droplets were finely dispersed. 3) In the homogenizing step the higher pressure results in the finer dispersion but as the pressure goes up, the differential efficiency of dispersion was decreased.

• Journal of the Korean Society of Clothing and Textiles
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• v.21 no.3
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• pp.632-640
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• 1997

Changes in surface properties and detergency of sunactant mixtures were investigated in order to study the optimum mixing ratio of anionic and nonionic surfactants by measuring surface tension, interfacial tension, suspendability, and emulsification as a Amction of mixing ratio. Also, surface tension and detergency of the surfactant mixtures were determined with the increase of water-hardness or temperature. The results were as follows: the addition of NPE to anionic surfactant solutions (LAS or SDS) by 0.1 mole fraction remarkably decreased surface tension. NPE (n=15)/anionic surfactant mixtures showed a synergistic effect in lowering interfacial tension and emulsification, but NPE (n=7.5)/anionic surfactant mixtures did not. In suspension stability, however, synergism appeared when LAS or 505 was mixed with both of NPE's. With respect to the hydrophile of NPE, NPE (n=15) was more effective than NPE (n=i.5) in improving suspension stability. Detergency of LAS/NPE mixture changed almost linearly with mixing ratio, but that of SDS/NPE mixture increased remarkably by the addition of 0.1 or 0.2 mole fraction of NPE at all temperatures. As the temperature increased, surface tension of surfactant mixtures decreased and detergency was improved, but their synergistic effect decreased. In hard water, the mixtures showed better detergency than single surfactuant solutions.

• Journal of Korean Society of Water and Wastewater
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• v.11 no.4
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• pp.63-70
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• 1997

The objectives of this study were to find out the optimum treatment conditions for removing nitrogen in a synthetic wastewater by using microorganisms immobilized with PVA-Freezing method. The samples used as influents to the laboratory scale treatment units were a synthetic wastewater. The experiments in this study were mainly directed to collect the data of nitrogen and organic matter removal efficiencies for the different hydraulic and internal recycle rates conditions, temperature and influent C/N ratios. The removal efficiencies of nitrogen and organic matters were investigated for the operating conditions of HRT 2~12hours, internal recycle rates 50~400%, temperatures $15{\sim}30^{\circ}C$ and C/N ratios 2.5~7.5. The adequate internal recycle rate for removing T-N and $BOD_5$ in the synthetic wastewater was found to be about 300% at the temperature of $30^{\circ}C$ when the ratio of carbon contents to the nitrogen (C/N) in the influent was around 5.5. Under these conditions, the final effluent concentrations of T-N and $BOD_5$ were 8.7 and 8.4 mg/l, respectively.

• Computers and Concrete
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• v.23 no.5
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• pp.351-359
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• 2019

In this study, the calcium hydroxide, an inherent product of cement hydration, was treated using biomimetic carbonation method of incorporating stearic acid to generate the hydrophobic calcium carbonate on concrete surface. Carbonation reaction was carried out at various $CO_2$ pressure and temperatures and utilizing the Scanning Electron Microscope (SEM), chloride-ion penetration test apparatus, and compression test machine to investigate the hydrophobicity, durability, and mechanical properties of the synthesized products. Experimental results indicate that the calcium stearate may change the surface property of concrete from hydrophilicity to hydrophobicity. Increasing reaction temperature can change the particles from irregular shapes to needle-rod structures with increased shear stress and thus favorable to hydrophobicity and microhardness. The contact angle against water for the concrete surface was found to increase with increasing $CO_2$ pressure and temperature, and reached to an optimum value at around $90^{\circ}C$. The maximum static water contact angle of 128.7 degree was obtained at the $CO_2$ pressure of 2 atm and temperature of $90^{\circ}C$. It was also found that biomimetic carbonation increased the permeability, acid resistance and chloride-ion permeability of the concrete material. These unique results demonstrate that the needle-rod structures of $CaCO_3$ synthetized on concrete surface could enhance hydrophobicity, durability, and mechanical properties of concrete.

• Korean Journal of Ecology and Environment
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• v.34 no.4 s.96
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• pp.337-341
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• 2001

Studies were conducted to determine the effects of water temperature on the number of spawning, egg production, spawning intervals and hatching success of Chinese bleak, Aphyocypris chinensis. Adult fish were exposed to water temperatures of 19, 22, 25 and $28{\circ}^C$ for two months in the laboratory. The spawning number, egg productivity, and hatching rate increased as water temperature increased between $19{\circ}^C$ and $25{\circ}^C$. Maximum egg production and hatching rate occurred at $25{\circ}^C$, whereas the spawning intervals decreased as water temperature increased except for the treatment of $28{\circ}^C$. The shortest spawning interval observed at $25{\circ}^C$.

• Food Science and Biotechnology
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• v.18 no.4
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• pp.985-990
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• 2009

Response surface methodology (RSM) was applied to determine the optimum drying conditions for pork jerky. The physicochemical properties of pork jerky, such as final moisture content, water activity (Aw), pH, and shear force were investigated. In addition, sensory characteristics of pork jerky were evaluated and were used as a parameter for determining the optimum condition. Pork jerky samples were dried at different temperatures between 40 to $80^{\circ}C$ for the time ranged from 0 to 10 hr. The predicted values for moisture content, Aw, and shear force of dried pork samples were in good agreement with the experimental values with correlation coefficients ($R^2$) of 0.95, 0.96, and 0.97, respectively. Both drying temperature and time significantly (p<0.01) affected moisture content, Aw, pH, and shear force and their interactions were also significant at p<0.01 except for Aw. RSM showed the optimum drying conditions for pork jerky, based on moisture content, shear force, and sensory evaluation to be oC$65-70^{\circ}C$ for 7-8 hr.