• Journal of Biosystems Engineering
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• v.39 no.4
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• pp.336-344
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• 2014

Purpose: In this study, the effect of milling on paddy rice stored at low temperature, the changes in grain temperature of bulk storage bags exposed at room temperature, the post-milling water content of paddy rice, the whiteness of rice, and the rate of pest incidence were investigated and data were analyzed. Methods: Changes in temperature inside the bulk storage bags kept at low temperature and grain temperature after exposure to room temperature were measured. Experiments were conducted for identifying the reasons of post-milling quality changes in paddy rice stored at low temperature. Results: It was determined that a short-term increase of water content in paddy rice was directly related to surface condensation, and that rice should be milled at least 72 h after removal from low-temperature storage, in order to completely eliminate surface condensation of paddy rice kept in bulk storage bags. It was observed that post-milling quality of rice changed, but water content was maintained at high levels for more than 18 d in rice that was milled when condensation occurred, regardless of paper or vinyl packaging. Rice whiteness rapidly decreased in rice that was milled when condensation occurred, regardless of packaging, while rice that was milled 72 h or more after removal from low temperature storage did not show any significant changes in whiteness. No pest incidence was observed up to 12 d after removal from low temperature storage, regardless of packaging. Starting at 18 d, after removal from low temperature storage, rice that was milled when condensation occurred, was affected by pests, while 24 d after removal from low temperature storage, all portions of rice were affected by pests. Conclusions: Our results suggest that changes in post-milling quality of rice could be significantly reduced by exposing paddy rice to room temperature for at least 72 h before milling, in order to allow the increase of grain temperature and prevent surface condensation.

• Journal of Energy Engineering
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• v.14 no.2 s.42
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• pp.73-81
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• 2005

An Experimental study was conducted to investigate the effective way for fuel consumption improvement in radiant tube burner heating system used in steel manufacturing process. To find effectiveness of increase of temperature and oxygen fraction of intake air on fuel consumption, the model radiant tube burner heating system with recuperator was designed to be able to adjust temperature and oxygen fraction of intake air, and was operated under various conditions with oxygen concentration in exhaust gas changed. The results show that burner chamber temperature was increased about $10\%$ of intake air temperature increase. so it was difficult to expect fuel consumption improvement. But only 1 or $2\%$ increase of oxygen fraction in intake air made a significant improvement in fuel consumption even though it made much NOx emissions also. Therefore, if NOx emissions is controlled under regulation with burner modification, it is expected that increase of oxygen fraction in Intake air is effective way to improve fuel consumption.

• Journal of the Korean Geotechnical Society
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• v.16 no.4
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• pp.157-170
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• 2000

In this study, we conducted a combined adsorption-sequential extraction analysis(CASA) to investigate temperature effects of single and competitive adsorption of zinc and copper on natural clays. As a result, it was found out that in a single adsorption of zinc, the adsorption was mostly in the exchangeable phase, with increase n temperature. In a competitive adsorption of zinc, this trend was so strong that the exchangeable phase adsorption increase up to 80~90%. On the other hand, about 50% of copper was adsorbed in the carbonate occluded phase in single and competitive adsorptions. In the single adsorption the adsorption of carbonate occluded phase increased by 5% with the temperature increase and in the competitive adsorption the increase rate is about twice. The adsorption of zinc and copper on natural clays is an endothermic reaction with the exception of exchangeable phase adsorption.

• Journal of Environmental Science International
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• v.18 no.4
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• pp.423-434
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• 2009

In recent years, the urban thermal environment has become worse, such as days on which the temperature goes above $30^{\circ}C$, sultry nights and heat stroke increase, due to the changes in terrestrial cover such as concrete and asphalt and increased anthropogenic heat emission accompanied by artificial structure. The land use type is an important determinant to near-surface air temperature. Due to these reasons we need to understand and improve the urban thermal environment. In this study, the fifth-generation Pennsylvania State University-National Center for Atmospheric Research Mesoscale Model(MMS) was applied to the metropolitan of Daegu area in order to investigate the influence of land cover changes and urban modifications increase of Albedo to the surface energy budget on the simulated near-surface air temperature and wind speed. The single urban category in existing 24-category U.S. Geological survey land cover classification used in MM5 was divided into 6 classes to account for heterogeneity of urban land cover. As a result of the numerical simulation intended for the metropolitan of Daegu assumed the increase of Albedo of roofs, buildings, or roads, the increase of Albedo (Cool scenario)can make decrease radiation effect of surface, so that it caused drops in ambient air temperature from 0.2 to 0.3 on the average during the daylight hours and smaller (or near-zero) decrease during the night. The Sensible heat flux and Wind velocity is decreased. Modeling studies suggest that increased surface albedo in urban area can reduce surface and air temperatures near the ground and affect related meteorological parameters such as winds, surface air temperature and sensible heat flux.

• Korean Journal of Materials Research
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• v.30 no.10
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• pp.502-508
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• 2020

This paper focuses on the electrical properties and stability against DC accelerated aging stress of ZnO-V₂O₅-MnO₂-Nb₂O₅-Bi₂O₃-Co₃O₄-Dy₂O₃ (ZVMNBCD) varistor ceramics sintered at 850 - 925 ℃. With the increase of sintering temperature, the average grain size increases from 4.4 to 11.8 mm, and the density of the sintered pellets decreases from 5.53 to 5.40 g/㎤ due to the volatility of V₂O₅, which has a low melting point. The breakdown field abruptly decreases from 8016 to 1,715 V/cm with the increase of the sintering temperature. The maximum non-ohmic coefficient (59) is obtained when the sample is sintered at 875 ℃. The samples sintered at below 900 ℃ exhibit a relatively low leakage current, less than 60 mA/㎠. The apparent dielectric constant increases due to the increase of the average grain size with the increase of the sintering temperature. The change tendency of dissipation factor at 1 kHz according to the sintering temperature coincides with the tendency of the leakage current. In terms of stability, the samples sintered at 900 ℃ exhibit both high non-ohmic coefficient (45) and excellent stability, 0.8% in 𝚫E_B/E_B and -0.7 % in 𝚫α/α after application of DC accelerated aging stress (0.85 E_B/85 ℃/24 h).

• Proceedings of the Ginseng society Conference
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• 1980.09a
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• pp.151-170
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• 1980

Physiological response of Panax ginseng var. atropurpureacaulo (purple stem variety, Pg) to light was reviewed through old literatures and recent experiments. Canopy structure, growth, pigment, leaf anatomy, disease occurence, transpiration, photosynthesis (PS), leaf saponin, photoperiodism and nutrient uptake were concerned. P. ginseng var. xanthocarpus (yellow berry variety, Px) and Panax quinquefolius(Pq) were compared with Pg if possible. Compensation point(Cp) increased with increase of light and ranged from 110 to 150 at $20^{\circ}C$ but from 140 to 220 at $30^{\circ}C$ with 4 to 15 Klux indicating occurence of light and temperature-dependent high photorespiration. Characteristics of Korea ginseng to hate high temperature was well accordance with an observation 2000 years ago. Korea ginseng showed lower Cp and appeared to be more tolerant to high light intensity and temperature than American sheng although the latter showed greater PS, stomata frequency and conductance, chlorophyll and carotenoids. Px showed lower PS than Pg probably due to higher Cp. Total leaf saponin was higher in leaves grown under high light. Ratio or diol saponin and triol saponin(PT/PD) decreased with increase of light intensity during growing mainly due to decrease of ginsenoside $Rg_1$ but increase of ginsenoside Rd. Leaves of Pg and Px had $Rg_1$ but no $Rb_3$ which was only found as much as $20\%$ of total in Pq leaves, and decreased with increase of light intensity. Re increased in Pg and Px but decreased in Pq with increase of light. PT/PD in leaf ranged 1.0-1.5 in Pg and Px but around 0.5 in Pq. Korea ginseng has Yang characteristics(tolerant to high light and temperature), cultured under Eum(shade) condition and long been used for Yang efficacy (to build up energy) while Pq was quite contrary. Traditional low light $intensity(3-8\%)$ for Korea ginseng culture appeared to be strongly related to historical unique quality. Effect of light quality and photoperiodism was not well known. Experiences are long but scientific knowledge is short for production and quality assessment of ginseng. Recent scientific knowledge of ginseng should learn wisdom from old experiences.

• Food Science of Animal Resources
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• v.38 no.6
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• pp.1294-1304
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• 2018

The aims of this research were to examine the effect of heating temperature (65, 75, and $85^{\circ}C$) and $CaCl_2$ concentration level (3, 4, and 5 mM) on the physicochemical properties of ${\beta}$-lactoglobulin (${\beta}$-lg) nanoemulsions (NEs) and to study how the droplet size of NEs affects the bioaccessibility (BA) of coenzyme $Q_{10}$ ($CoQ_{10}$). The droplet size of NEs and BA of $CoQ_{10}$ was assessed by particle size analyzer and UV-Vis spectrophotometer, respectively. An increase in heating temperature and $CaCl_2$ concentration level resulted in a significant (p<0.05) increase in the droplet size of NEs while there were no significant differences in polydispersity index and zeta-potential of NEs. When NEs containing $CoQ_{10}$ were incubated in simulated small intestinal phases, an increase in the droplet size and polydispersity index of NEs was observed. This indicated that NEs were not stable in small intestine and digestion of NEs occurred. As heating temperature and $CaCl_2$ concentration level were decreased, a significant (p<0.05) increase in BA of $CoQ_{10}$ was observed. There was a significant (p<0.05) increase in BA of $CoQ_{10}$ with a decrease in the droplet size of NEs. In conclusion, heating temperature and $CaCl_2$ concentration level were key-parameters affecting the initial droplet size of NEs and BA of $CoQ_{10}$ was negatively correlated with initial droplet size of NEs.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.7
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• pp.1050-1056
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• 2014

This study investigated the main factors influencing digester temperature and methods to reduce heat losses during the cold season in the subtropics. Four composite digesters (two insulated and two uninsulated) were buried underground to measure their internal temperature ($^{\circ}C$) at a depth of 140 cm and 180 cm, biogas production and methane ($CH_4$) concentration in biogas from August to February. In parallel the temperature of the air (100 cm above ground), in the slurry mixing tank and in the soil (10, 100, 140, and 180 cm depth) was measured by thermocouple. The influent amount was measured daily and the influent chemical composition was measured monthly during the whole experimental period. Seasonal variations in air temperature significantly affected the temperature in the soil, mixing tank and digester. Consequently, biogas production, which is temperature dependent, was influenced by the season. The main factors determining the internal temperature in the digesters were insulation with Styrofoam, air temperature and temperature of slurry in the mixing tank. Biogas production is low due to the cold climate conditions in winter in Northern Vietnam, but the study proved that storing slurry in the mixing tank until its temperature peak at around 14:00 h will increase the temperature in the digester and thus increase potential biogas production. Algorithms are provided linking digester temperature to the temperature of slurry in the mixing tank.

• Journal of Environmental Science International
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• v.17 no.5
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• pp.485-491
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• 2008

The present study examined the relation between land cover condition and temperature in various types of urban green spaces. The diagram of temperature distribution showed that high-temperature zones are formed around paved areas, and low temperature zone around planted areas and grassy areas. Even in planted areas where low-temperature zones were formed, temperature was different according to hierarchical structure. That is, temperature was relatively low in areas covered with arbor + sub-arbor. With regard to land cover ratio, the increase of planted areas and grassy areas had an effect on the fall of temperature and the effect was higher in order of planted areas and grassy areas. On the contrary, paved areas and bare areas had an effect on the rise of temperature. According to the results of factor analysis, in case of the highest temperature, planted area and grassy area were put together into a factor lowering temperature, paved area and temperature into a factor raising temperature, and bare area alone into a factor of low significance. In case of the lowest temperature, grassy area and bare area were put together into a factor, and the validity of the factor analysis was proved by the analysis of urban heat islands. An increase in the number of trees by height was effective in lowering temperature, and the effect was high in order to arbor and sub-arbor, and the source of coldness in planted area was tall trees.

• Journal of Sensor Science and Technology
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• v.26 no.2
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• pp.141-147
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• 2017

A pressure sensor in pulse measurement system is a core component for precisely measuring the pulse waveform of radial artery. A pulse sensor signal that measures the pulse wave in contact with the skin is affected by the temperature difference between the ambient temperature and skin surface. In this study, we found experimentally that the signal changes of the pressure sensors and a temperature sensor were caused by the temperature of the wrist surface while the pressure sensor was contacted on the skin surface for measuring pulse wave. To observe the signal change of the pulse sensor caused by temperature increase on sensor surface, Peltier device that can be kept at a set temperature was used. As the temperature of Peltier device was kept at $35^{\circ}C$ (the maximum wrist temperature), the device was put on the pulse sensor surface. The temperature and pressure signals were obtained simultaneously from a temperature sensor and six pressure sensors embedded in the pulse sensor. As a result of signal analysis, the sensor pressure was decreased during temperature increase of pulse sensor surface. In addition, the signal difference ratio of pressure and temperature sensors with respect to thickness of cover layer in pulse sensor was increased exponentially. Therefore, the signal of pressure sensor was modified by the compensation equation derived by the temperature sensor signal. We suggested that the thickness of cover layer in pulse sensor should be designed considering the skin surface temperature.