• Title/Summary/Keyword: Dry heat

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Fixed Bed Drying of Sugarcane Bagasse Using Solar Energy

  • Hyoung-Woo LEE;Hyun-Ook KIM;Dong-Hoon LEE;Don-Ha CHOI;Seung-Gyu KIM
    • Journal of the Korean Wood Science and Technology
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    • v.52 no.1
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    • pp.47-57
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    • 2024
  • Solar energy is one of the most promising options for renewable energy and biomass is one of them. One of the main biomass sources, sugarcane bagasse, is produced annually in more than hundreds of nations worldwide exceeding 4.25 billion tons. To dry a 900-mm deep fixed bed of wet sugarcane bagasse, a solar air heater with a collector area of 2 m2 was installed. Between October 10th to 19th in Gwangju, South Korea, a 9-day drying period, the solar collector received a total of 496,145 kJ of solar radiation. During this time, 54.5 kg of water was extracted from 133 kg of wet sugarcane bagasse (average green moisture content of 47.6%w.b.). The estimated net heat from the evaporation of water removed during the dying period accounted for approximately 27% of the total solar radiation on the solar collector.

Temperature and humidity characteristics of waste glass aggregate-based vegetation blocks using smart environmental sensor (스마트 환경 센서를 활용한 폐유리 골재 기반 식생블록의 온/습도 특성)

  • Gil, Min-Woo;Kim, Gyu-Yong;Pyeon, Su-Jeong;Choi, Youn-Sung;Park, Jong-Yeop;Nam, Jeong-Soo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2023.11a
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    • pp.51-52
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    • 2023
  • Recently, heat island and dry island phenomena occur frequently due to land surface development and excessive energy consumption in urban areas. As a result, the surface temperature of the building and the entire temperature of its surroundings are increased, and as a result, the durability of the building is rapidly deteriorated. In order to suppress these causes, a method of maintaining the temperature of road heating wires was implemented as a temporary measure, but this did not predict climate change. Therefore, this study is a method to measure the compressive strength, density, and thermal conductivity of light weight concrete using waste glass foam beads. After fabricating a simple chamber, the temperature and humidity of the inside and outside were measured with an Arduino device in consideration of external factors. Therefore, if waste glass foam beads made through proper mixing are constructed in the urban center, the quality of the urban can be improved.

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Pigment Stability of Lavers Porhyra tenera Kjellman during Processing and Storage (김의 가공 저장중에 있어서의 색소의 안정도)

  • LEE Kang-Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.2 no.2
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    • pp.105-133
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    • 1969
  • The stability of three major pigments in lavers, namely chlorophylls, carotenoids, and phy-cobilins, during processing and storage was studied. The results of the pigment retention in fresh lavers during storage at low temperatures, of heat lability during heat treatment, and of the pigment loss during storage are summarized as follows: 1. The contents of chlorophyll a, xanthophyll (lutein+zeaxanthin), and carotene ($\alpha-+\beta-carotene$) averaged 1,525, 627, and $409{\mu}g/g$ of dry samples respectively The comparative composition of four carotenoids, lutein, $\beta-carotene$, zeaxanthin, and $\alpha-carotene$, was 35.9, 33.7, 12.2, and $5.8\%$ respectively. 2. In storage of fresh lavers at room ternperature ($20-25^{\circ}C$), 2 to $5^{\circ}C$, and $-15^{\circ}C$, the pigments generally were retained more at 2 to $5^{\circ}C$ than others while carotene only showed more retention at $-15^{\circ}C$ than at 2 to $5^{\circ}C$. Phycocyanin tended to decrease more rapidly than phyco-erythrin at low temperatures. 3. In regard to heat treatment of both dried and wet materials at 40, 60, 80, $100^{\circ}C$ respectively, the pigments were more stable at lower temperatures than at higher temperatures in both cases of materials. Carotenoids were retained more in wet materials than in the sun dried. Xanthophylls showed higher heat stability than carotenes. Phycoerythrin was considered more heat labile than phycocyanin, particularly at higher temperatures. 4. In storage of heat treated lavers for 50 days at room temperature, the retention of pigments appeared differently in accordance with the temperatures of treatment The materials treated at $60^{\circ}C$ showed better relention of pigments than those treated at the other temperatures. Degradation rate of xanthopllylls, carotenes, and phycobilins was decreased in the materials treated at higher temperatures, showing a tendency of great pigment retention even for a long period storage. Chlorophyll il was retained more in sun dried materials whereas xanthophyll and carotene were retained more in the wet. 5. In order to maintain a higher pigment stability during storage, the materials must be treated at $60^{\circ}C$ in a dryer with rapid ventilation until the moisture level reaches about $6.0\%$. In case of treatment at a higher temperature than $60^{\circ}C$, they must be treated for a short period of time to minimize pigment degradation by heat. 6. The lavers treated with the solutions of pH around 7.8 showed a higher retention of chlorophyll a. When treated with the solutions of algal extracts such as agar and alginic acid, uniform layer of laver sheets and better surface gloss of dried layers were obtained.

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A Study on Changes in Feed Digestibility and Establishment of Energy Requirement for Maintenance of Growing Hanwoo Steers under Severe Heat Stress (심각한 열스트레스에 의한 육성기 거세한우의 사료 소화율 변화 탐색 및 유지를 위한 에너지 요구량 설정 연구)

  • Cho, Yu Kyung;Choi, Seong Ho;Han, Ouk Kyu;Park, Joung Hyun;Choi, Chang Weon
    • Journal of agriculture & life science
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    • v.50 no.5
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    • pp.163-172
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    • 2016
  • Four growing Hanwoo cattle weighing 200±11.7kg were used within 4×4 Latin square design to establish nutrient requirements for Hanwoo growing steers under severe heat stress. The steers were fed four different energy level diets; 100%(control), 100%(E100), 115%(E115) and 130%(E130) of energy levels of growing Hanwoo steers based on total digestible nutrient level suggested by the Korea Feeding Standard for Hanwoo using timothy hay and commercial concentrate. The steers in the control were housed with no stress, whereas the steers in the other groups were under severe heat stress. The severe heat stress significantly decreased(p<0.05) true digestibility of dry matter(i.e. control 81.5% vs E100 79.1, E115 77.0 and E130 76.0, respectively). The severe heat stress and different energy intake levels did not affect blood physiological metabolites and body temperature of the growing steers. Based on changes in average daily gain by different energy intake level, the equation(Y=0.235X+115.03) of energy requirement of growing Hanwoo steers without changes in body weight was calculated, indicating that, compared with the present energy intake suggested by Korean feeding standard, 15.03% of dietary energy for maintenance of growing Hanwoo steers under severe heat stress should be increased.

Relationship between Ocean-Meteorological Factors and Snowfall in the Western Coastal Region of Korea in Winter (동계 한국 서부연안지역의 적설과 해양기상요소와의 관계)

  • Go, Woo-Jin;Kim, Sang-Woo;Jang, Lee-Hyun
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.15 no.1
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    • pp.17-24
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    • 2009
  • This study was conducted to find out the effects of relationship between ocean-meteorological factors and snowfall at Incheon, Gunsan and Mokpo when cold and dry continental air mass passed through the West Sea of Korea in winter. Mean snowfall from December to February showed the order of Gunsan (12.7 cm), Mokpo (9.0 cm) and Incheon (7.8 cm). In particular, the snowfall in the three regions showed the regional difference in December and February. It was well consistent with the extension of continental high. Extension of continental high can cause effect on snowfall at the west regions (Inchoen, Gunsan, Mokpo) of the Korean Peninsula. The continental high extended from the southern China to western coastal region of the Korean Peninsula in December, it extended from the northern China to central area of the Korean Peninsula in January. It also extended from the north side of China through Bohai Sea and Yodong Peninsula to central area of the Korean Peninsula in February. Therefore, more snowfall recorded in Incheon is higher in February than December whereas Gunsan and Mokpo is the opposite. The heavy snowfall at the three regions was caused by loss of the heat from the ocean to air when the heat loss was higher than 100 $W/m^2$. The heavy snowfall was also observed when the arrangement of continental high atmospheric pressure and low pressure was high at the west and low at the east, which formed a front in West and when the wind blow from the North or North West at the speed of 4${\sim}$8 m/sec.

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Net energy content of rice bran, corn germ meal, corn gluten feed, peanut meal, and sunflower meal in growing pigs

  • Li, Yakui;Li, Zhongchao;Liu, Hu;Noblet, Jean;Liu, Ling;Li, Defa;Wang, Fenglai;Lai, Changhua
    • Asian-Australasian Journal of Animal Sciences
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    • v.31 no.9
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    • pp.1481-1490
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    • 2018
  • Objective: The objective of this experiment was to determine the net energy (NE) content of full-fat rice bran (FFRB), corn germ meal (CGM), corn gluten feed (CGF), solvent-extracted peanut meal (PNM), and dehulled sunflower meal (SFM) fed to growing pigs using indirect calorimetry or published prediction equations. Methods: Twelve growing barrows with an average initial body weight (BW) of $32.4{\pm}3.3kg$ were allotted to a replicated $3{\times}6$ Youden square design with 3 successive periods and 6 diets. During each period, pigs were individually housed in metabolism crates for 16 d, which included 7 days for adaptation. On d 8, the pigs were transferred to the respiration chambers and fed one of the 6 diets at 2.0 MJ metabolizable energy (ME)/$kg\;BW^{0.6}/d$. Total feces and urine were collected and daily heat production was measured from d 9 to d 13. On d 14 and d15, pigs were fed at their maintenance energy requirement level. On the last day pigs were fasted and fasting heat production was measured. Results: The NE of FFRB, CGM, CGF, PNM, and SFM measured by indirect calorimetry method was 12.33, 8.75, 7.51, 10.79, and 6.49 MJ/kg dry matter (DM), respectively. The NE/ME ratios ranged from 67.2% (SFM) to 78.5% (CGF). The NE values for the 5 ingredients calculated according to the prediction equations were 12.22, 8.55, 6.79, 10.51, and 6.17 MJ/kg DM, respectively. Conclusion: The NE values were the highest for FFRB and PNM and the lowest in the corn co-products and SFM. The average NE of the 5 ingredients measured by indirect calorimetry method in the current study was greater than values predicted from NE prediction equations (0.32 MJ/kg DM).

Effects of Heat-oxidized Soy Protein Isolate on Growth Performance and Digestive Function of Broiler Chickens at Early Age

  • Chen, X.;Chen, Y.P.;Wu, D.W.;Wen, C.;Zhou, Y.M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.4
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    • pp.544-550
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    • 2015
  • This study was conducted to investigate effects of heat-oxidized soy protein isolate (HSPI) on growth performance, serum biochemical indices, apparent nutrient digestibility and digestive function of broiler chickens. A total of 320 1-day-old Arbor Acres chicks were randomly divided into 4 groups with 8 replicates of 10 birds, receiving diets containing soy protein isolate (SPI, control group) or the same amount of SPI heated in an oven at $100^{\circ}C$ for 1, 4, or 8 h, for 21 days, respectively. The results indicated that compared with the control group, body weight gain and feed intake of birds fed diet containing SPI heated for 8 h were significantly lower (p<0.05). Serum urea nitrogen concentration was higher in the broilers fed diet containing SPI heated for 4 or 8 h at d 21 (p<0.05). In contrast, serum glucose content was decreased by HSPI substitution at d 21 (p<0.05). The relative pancreas weight in HSPI groups was higher than that in the control group at d 21 (p<0.05). Meanwhile, the opposite effect was observed for relative weight of anterior intestine and ileum in broilers fed a diet containing SPI heated for 8 h (p<0.05). Birds fed diets containing SPI heated for 4 or 8 h had a decreased lipase activity in anterior intestinal content at d 14 and 21 (p<0.05), respectively. In addition, the same effect was also noted in broilers given diets containing SPI heated for 1 h at d 21 (p<0.05). Similarly, amylase, protease and trypsin activity in anterior intestinal content were lower in broilers fed diets containing SPI heated for 8 h at d 21 (p<0.05). The apparent digestibility of dry matter (DM) from d 8 to 10 and DM, crude protein (CP), and ether extract from d 15 to 17 were lower in broilers fed diets containing SPI heated for 8 h (p<0.05). Besides, birds given diets containing SPI heated for 4 h also exhibited lower CP apparent digestibility from d 15 to 17 (p<0.05). It was concluded that HSPI inclusion can exert a negative influence on the growth performance of broilers, which was likely to result from the simultaneously compromised digestive function.

A Literature Study on the Cervical Lymphic Node (나역에 대한 文獻的 考察(處方과 藥物을 중심으로))

  • Min, Young-gye;Jeong, Dong-hwan;Sim, Sang-Hui;Park, Su-yeon;Kim, Jong-han;Choi, Jung-hwa
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.16 no.2
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    • pp.1-45
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    • 2003
  • We get the conclusion this following through bibliographic consideration about the cause of disease, disease mechanisms and remedy, prescription of tuberculosis of the cervical lymphic node. 1. The tuberculosis of the cervical Iymphic node is named the linear lump of scrofula(마도라력), the scrofula around neck(반사력), the wide-spread scrofula(류주력), the papule like lotus seed(련자력), the scrofula(라력), the subcutaneous nodes(結核), the scrofula due to disorder of Gi(기력) and the scrofula due to accumulation of phlegm(담력) according to the criterion of regions of disease, causes, rounding parts and shapes. 2. The cause of the tuberculosis of the cervical lymphic node are the stagnation of liver Gi(肝氣鬱結), the accumulation of phlegm and the stagnation of Gi(痰凝氣滯), the deficiency of vital essence of the liver and kidney(肝腎陰虛), the wind-heat of liver, gallbladder and triple warmer(肝膽三焦風熱), the dry-fire(燥火), the dryness of blood(血燥), the unwholesome diet(飮食不潔), the abundance of diet(食味之厚), the stagnation of Gi(鬱氣之積), the exhaustion syndrome(虛勞), the excessive thought(思慮過多), the toxin of wind-heat(風熱毒) and the germ of subcutaneous nodes(結核菌). 3. Symptoms of the tuberculosis of the cervical lymphic node are swelling slowly in comparison in the early days of occurrence, and are not pain, not itch, not heat, not other special symptoms. But in some cases, tuberculosis of the cervical lymphic node are quickly swelling in the early days of occurrence, and the fever and pain appear, The pyosis is accompanied with the fever and the pain at first generally, and then removing the pus from abscess is dissolved the fever and the pain in the majority of cases and representative of the general exhaustion syndrome. 4, The remedy of tuberculosis of the cervical Iymphic node is the early days, clearing the liver and relieves constraint(疏肝解鬱), phlegm and dissolving accumulation(化痰散結) the middle days, pus draining and toxin expelIing(托裏透膿) the latter days, replenish the kidney and strengthen the spleen(滋腎健脾). 5. The medication to treat the tuberculosis of the cervical lymphic node are the 益氣養榮湯(lkgiyangyoungtang)(14th), the 夏枯草散(Hagochosan)(10th) and et cetra in regular sequence. 6. The herb to treat the tuberculosis of the cervical Iymphic node are the 連翹(FRUCTUS FORSYTHlAE)(59th), the 甘草(RADIX GLYCYRRHIZAE)(51th), the 當歸(RADIX ANGELICAE GlGANTIS)(47th), the 黃芩(RADlXSCUTELLARIAE)(40th), the 夏枯草(SPICA PRUNELLAE)(23th) in regular sequence.

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Snowfall and Ocean Conditions Characteristic in the West Sea of Korea in Winter (동계 서해의 해황과 적설 특성)

  • Go, Woo-Jin;Kim, Sang-Woo;Jang, Lee-Hyun;Choi, Yong-Kyu;Yang, Joon-Yong
    • Proceedings of KOSOMES biannual meeting
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    • 2008.05a
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    • pp.185-189
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    • 2008
  • This study was conducted to find out the effects of relationship between ocean conditions and snowfall when cold and dry continental air mass passes through the West Sea of Korea. Route of continental high atmospheric pressure can cause effect on snowfall at the west regions (Inchoen, Gunsan, Mokpo) of the Korean Peninsula. The continental high atmospheric pressure extend from the southern China to western coastal region of the Korean Peninsula during the December, and it extend from the north side of China through Bohai Sea and Yodong Peninsula to central area of the Korean Peninsula during the February. Therefore, more snowfall recorded in Incheon is higher during Feb. than Dec.. whereas Gunsan and Mokpo is the opposite. The heavy snowfall at the western coastal region of Korea was caused by loss of the heat from the ocean to air when it's higher than $100W/m^2$. the heavy snowfall was also observed when the arrangement of continental high atmospheric pressure and low pressure was high at the West and low at the East, which formed a front in West and when the wind blow from the North or North West at the speed of $4\sim8m/sec$. There were not much relation between salinity in the western sea and snowfall in the western coastal region of Korea.

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A Study on the Combustion Characteristics of the Crown of Pine Trees in the Drying Season (건조기 소나무 수관부 부위별 연소특성에 관한 연구)

  • Hyuk Kwon;Jong Ho Lee
    • Journal of the Korean Society of Safety
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    • v.38 no.4
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    • pp.39-46
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    • 2023
  • Pine trees, which account for 23% of the forested area of the Republic of Korea, are highly vulnerable to fire in comparison to broad-leaved trees due to the presence of consistent water tube sections throughout the year and resin that is composed of approximately 20% oil. In addition, the pattern of forest fires is determined by weather, topographic conditions, and fluctuation in moisture content. Therefore, when fire breaks out in pine tree forests during the dry season (January to March), it is difficult to extinguish, and it quickly spreads. In this study, the combustion characteristics of pine needles, pine cones, and pine branches in the water tube sections of living pine trees were compared and analyzed in accordance with the moisture content as per the ISO 5660-1. The monthly moisture content was analyzed from January to March, and it was found to be the lowest in March, with 53.6% for pine needles, 51.9% for pine branches, and 10.9% for pine cones. In particular, pine cones were more vulnerable to fire as compared to pine needles and pine branches because their moisture content was more than five times lower than that of pine needles and branches. The ignition time, which affects the speed of flame propagation, was the most rapid in March, and the fastest ignition time was for pine cones, at 19 seconds, followed by 34 seconds for pine needles, and 256 seconds for pine branches. The pine branches were the last to be ignited due to the effect of density, according to the thickness and specific gravity of the specimen. The peak heat release rate, which is a measurable index of fire intensity, was analyzed for pine cones and found to be 184.28 kW/m2 , while the mean effective heat of combustion was 19.79 MJ/kg, and the total heat release rate was 39.7 MJ/m2 , and these values were higher than those of pine branches and pine needles. Thus, we determined that the flame propagation speed and fire intensity according to the moisture content can be used to evaluate the risk of fire to the water tube section of pine trees. It is suggested that because of the combustion characteristics of the pine cone in March, that is when the forest is most vulnerable to fires.