• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.6
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• pp.524-531
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• 2001

The temperature and humidity distribution in a dry room are studied numerically by using standard$\kappa-\varepsilon$ turbulence model. In order to evaluate effective heat and moisture ventilation characteristics inside the room, the heat removal capacity and moisture exhaust efficiency are introduced. An effective ventilation control is analyzed by evaluating quantitatively temperature and humidity distributions. It was found that the mean absolute humidity inside the room was almost constant with approximately 0.1905g/kg air regardless of the models and the heat generation rates. This was believed that the moisture generation by workers was relatively small. 40% improvement of the critical decay time was achieved, through the modifications of design variables.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.05a
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• pp.337-338
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• 2013

Recent research is needed for the reduction of the pH of the recycled aggregates, recycled aggregates for alkali social problems have emerged. This was confirmed through preliminary experiments using a self-made reactor with dry ice, the possibility of reducing the pH of the recycled aggregates. The pH reduction of coarse recycled aggregates plant was made to apply the field to the middle of construction waste treatment process to reduce the pH of the plant room, and measured the pH change with time. The measurement results showed that dry ice after the reaction, the pH of the aggregate 5% reduction than untreated recycled aggregates.

• Journal of the Korean Wood Science and Technology
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• v.31 no.6
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• pp.15-21
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• 2003

Image processing technique was adapted for exploring the more convenient ways to investigate the drying characteristics of wood. The acquisition of information about drying characteristics is indispensable for the development or improvement of dry-kiln schedules. A small internal fan type wood dry kiln was combined with image-processing and data-acquisition systems to monitor continuously the formation of checks and moisture reduction during drying. All the images and data were analyzed to improve or estimate the dry-kiln schedules and predict the drying time which would be required to dry green wood to 10% moisture content in internal fan type kiln. Samples of 20 mm- and 50 mm-thick Metasequoia glyptostrobodies, Paulownia coreana Uyeki, Pinus densiflora Sieb. Et Zucc., Platanus occidentalis L., Quercus acutissima and Robinia pseudo-acacia were used to verify the potentiality of this technique.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.11
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• pp.1584-1592
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• 2014

The objective was to evaluate the ingestive behavior of crossbred heifers finished on a Brachiaria brizantha cv. Marandu pasture receiving four levels of glycerin in their supplementation. Thirty-six crossbred heifers with average initial weight of $264.83{\pm}3.83kg$ and 20 months of age were distributed into a completely randomized design with four treatments and nine replications: control (0%), 4.82%, 10.12%, and 15.56% glycerin in the dry matter. The grazing time reduced linearly (p<0.05), whereas the time spent on activities like rumination, idleness, trough and total chewing time were quadratically affected (p<0.05). Bite rate and number of bites/day were quadratically influenced (p<0.05). The number of bites/swallowed cud and the number of bites/minute, however, increased linearly (p<0.05). Although the time spent on each cud and number of chews per cud were not affected (p>0.05).The number of rumination periods reduced linearly (p<0.05), whereas the number of grazing, idle and trough periods, and the times per grazing, idle, rumination and trough periods were quadratically affected (p<0.05). The feed and rumination efficiencies of the dry matter, non-fibrous carbohydrates, pasture dry matter and concentrate were quadratically affected (p>0.05) whereas the feed efficiency of neutral detergent fiber reduced linearly (p<0.05). Addition of glycerin in substitution of corn in supplements for animals managed on pastures does not influenced feed intake, but reduces the grazing time and increases the idle time. The supplementation also improves feed and rumination efficiencies.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.8
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• pp.1164-1173
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• 2014

The present study demonstrates the impact of specific breed on the characteristics of dry-cured ham. Eighty thighs from Korean native pig (KNP), crossbreed (Landrace${\times}$YorkshireLandrace${\times}$Yorkshire)♀${\times}$Duroc♂ (LYD), Berkshire (Ber), and Duroc (Du) pig breeds (n = 10 for each breed) were used for processing of dry-cured ham. The thighs were salted with 6% NaCl (w/w) and 100 ppm $NaNO_2$, and total processing time was 413 days. The effects of breed on the physicochemical composition, texture, color and sensory characteristics were assessed on the biceps femoris muscle of the hams. The results revealed that the highest weight loss was found in the dry-cured ham of LYD breed and the lowest weight loss was found in Ber dry-cured ham. The KNP dry-cured ham contain higher intramuscular fat level than other breed hams (p<0.05). It was observed that the dry-cured ham made from KNP breed had the lowest water activity value and highest salt content, while the LYD dry-cure ham had higher total volatile basic nitrogen content than the Ber and Du hams (p<0.05). Zinc, iron and total monounsaturated fatty acids levels were higher in KNP ham while polyunsaturated fatty acids levels were higher in Du ham when compared to other breed hams (p<0.05). Additionally, the KNP dry-cured ham possessed higher Commission International de l'Eclairage (CIE) $a^*$ value, while the Du dry-cured ham had higher $L^*$, CIE $b^*$ and hue angle values (p<0.05). Furthermore, breed significantly affected the sensory attributes of dry-cured hams with higher scores for color, aroma and taste found in KNP dry-cured ham as compared to other breed hams (p<0.05). The overall outcome of the study is that the breed has a potential effect on the specific chemical composition, texture, color and sensorial properties of dry-cured hams. These data could be useful for meat processors to select the suitable breeds for economical manufacturing of high quality dry-cured hams.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.11
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• pp.1563-1567
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• 2017

Objective: The influence of substituting steam-flaked corn (SFC) for dry rolled corn (DRC) on feedlot cattle growth performance and dietary net energy when cattle are allowed either ad libitum or 2-h restricted access to the finishing diet was evaluated. Methods: Treatment effects were tested using 96 crossbred steers ($251{\pm}2kg$) during the initial 56 d of the finishing phase. Cattle were blocked by weight and randomly assigned within blocks to 16 pens (4 pens/treatment). Bunk space was sufficient (41 cm/head) to allow all steers access to the feed bunk at the same time. Treatments consisted of two finishing diets containing (dry matter basis) 77.1% corn grain processed by dry rolling (density = 0.50 kg/L) or steam flaking (density = 0.36 kg/L). Cattle were fed twice daily at 06:00 and 14:00 h, allowing for approximately 5% residual. In the case of restricted feeding, steers were allowed access to feeders for 1 h following each feeding, after which residual feed was withdrawn. Results: There were no treatment interactions on dry matter intake (DMI), average daily gain (ADG), gain efficiency (G:F), or dietary net energy (NE). Restricting feed access time reduced (p<0.01) feed intake, and hence, ADG. Substitution of SFC for DRC increased (p<0.01) ADG, feed efficiency (G:F), and estimated dietary NE, without affecting DMI. Based on tabular net energy of maintenance ($NE_m$) value (2.18 Mcal/kg) for DRC, the estimated $NE_m$ value for SFC using the replacement technique, averaged 2.44 Mcal/kg; an improvement of 10.7%. The ratio of observed-to-expected dietary NE was not affected by feed access time. Conclusion: Substitution of SFC for DRC in finishing diets for feedlot cattle enhanced ADG, gain efficiency, and the NE value of the diet. Although restriction of feed access time depressed DMI and ADG, it did not affect the comparative benefit of steam flaking toward enhancement of ADG, G:F, and dietary NE.

• Journal of Korean Clinical Health Science
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• v.11 no.1
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• pp.1616-1624
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• 2023

Purpose. The purpose of this study was to investigate the effect of changes in tear break-up time, accommodative response amount, and accommodative microwave on the eyes due to changes in humidity. Methods. A total of 48 adult men and women in their 20s (21.1±1.56 years old) were surveyed on dry eye questionnaires (OSID questionnaires), tear destruction time was measured by humidity (40%, 60%, 80%), and controlled reactions and controlled fine waves were measured through tactile tests. Result. As a result of the OSID questionnaire, there were 10 normal patients, 8 mild dry eyes, 1 moderate dry eye, and 5 severe dry eyes. The initial tear film destruction time was 7.34±4.67 seconds at 40% humidity, 8.99±4.75 seconds at 60% humidity, 10.26±4.52 seconds at 80% humidity, and the average tear film destruction time was 9.51±4.07 seconds at 40% humidity, 10.99±3.82 seconds at 60% humidity, and 12.05±3.42 seconds at 80% humidity. The accommodative response was -0.41~1.79D at 40% humidity, -0.34~1.79D at 60% humidity, and -0.30~2.01D at 80% humidity. The accommodative microwave was measured as 56.39~63.43dB when it was 40%, 56.41~62.64dB when it was 60%, and 55.96 ~61.13dB when it was 80%. Conclusion. As the humidity (40~80%) increased, the tear break-up time increased, and as the accommodative stimulus amount increased, the accommodative response amount increased. It was found that the accommodative microwave according to the amount of accommodative stimulation increased, and as the humidity increased, the accommodative microwave decreased.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.3
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• pp.24-32
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• 2011

[ $SF_6$ ]gas, which has an excellent dielectric strength and interruption performance, is used in various applications such as gas insulated switchgear (GIS) in substations. However, since $SF_6$ has a high global warming potential (GWP), it is necessary to find an eco-friendly alternative insulation gas. In order to examine the possibility of using alternative insulation gases for $SF_6$ in power distribution system equipment, the dielectric strength and physical phenomena of dry air in a quasi-uniform electric field are investigated experimentally in this paper. As a result, the breakdown voltages for positive polarity are higher than those for negative polarity under impulse voltage applications. The negative 50[%] flashover voltage, $V_{50}$ of dry air under conditions above 0.4[MPa] gas pressure, is higher than 150[kV], that is the basic impulse insulation level of distribution equipment. The $V_{50}$ increases linearly with increasing the gas pressure, regardless of the waveform and polarity of the applied impulse voltages. The voltage-time curves are dependent on the rise time of the impulse voltage and gas pressure. Furthermore, streamer discharge was observed through light emission images by an ICCD camera under impulse voltage applications.

• The Journal of the Korea Contents Association
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• v.11 no.9
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• pp.246-253
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• 2011

Several problems occurred due to the use of the wrong water cycle system in the watershed. This was caused by a dry stream in the lower parts of the tributaries and the deterioration in value of usage by water pollution in accordance with water storage. This was maintained for a long period of time in the reservoir which secured the agricultural water. As a result of the operational status in the agricultural reservoirs focused on Chungcheongnam-do and Daejeon metropolitan city, a dry stream appeared because hydraulic retention time(HRT) in the majority of reservoirs was maintained for 8 months of the year. The water quality in the agricultural reservoir was fairly related to the water cycle system due to rainfall and input of pollutants from the population and livestock in the watershed. Consequently, the storage water volume and the time period of the water in the reservoir should be controlled by the reduction of the pollution load in the water and the prevention of a dry stream. Also, the water cycle system in the watershed should be improved by maintaining a short HRT of the reservoir.

• Journal of the Korea Organic Resources Recycling Association
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• v.12 no.2
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• pp.52-60
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• 2004

The basic approach to sewage sludge is organic waste minimization, promotion of energy recovery; volume and weight reduction by final treatment, and environmentally final disposal of natural circulation. Dry and pyrolysis of maize was experimentally investigated in full-scale rotary kiln in semi-continuous operation. The operational parameters varied are the operating temperature $160{\sim}175^{\circ}C$ of dry and $450{\sim}800^{\circ}C$ of pyrolysis, the solids residence time 9 min for pyrolysis. Important parameters studied include the running time, water content of sewage sludge, solids amount of sewage sludge(TS%) by the varied temperature. Also, with the increasing of temperature, how the yield of oil and char product change was observed, and the distribution of gas production components was observed. The gas of $C_1{\sim}C_3$ yield increased and oil of $C_4{\sim}C_6$ yield decreased along with pyrolysis temperature of $670^{\circ}C$ by the run time of 9 min.