• Title/Summary/Keyword: green condition

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A Experimental Study on Nitrous Oxide Formation in Direct Injection Diesel Engine (직접분사식 디젤엔진에서 아산화질소의 생성에 관한 실험적 연구)

  • Yoo, Dong-Hoon
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.21 no.2
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    • pp.188-193
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    • 2015
  • It has been generally recognized that $N_2O$(Nitrous Oxide) emission from marine diesel engines has a close correlation with $SO_2$(Sulfur Dioxide) emission, and diversity of fuel elements using ships affects characteristics of the $N_2O$ emission. According to recent reports, in case of existence of an enough large NO(Nitric Oxide) generated as fuel combustion, effect of the $SO_2$ emission in exhaust gas on the $N_2O$ formation is more vast than effect of the NO. Therefore, $N_2O$ formation due to the $SO_2$ element operates on a important factor in EGR(Exhaust Gas Recirculation) systems for NOx reduction. An aim of this experimental study is to investigate that intake gas of the diesel engine with increasing of $SO_2$ flow rate affects $N_2O$ emission in exhaust gas. A test engine using this experiment was a 4-stroke direct injection diesel engine with maximum output of 12 kW at 2600rpm, and operating condition was set up at a 75% load. A standard $SO_2$ gas with 0.499%($m^3/m^3$) was used for changing of $SO_2$ concentration in intake gas. In conclusion, the diesel fuel included out sulfur elements did mot emit the $SO_2$ emission, and the $SO_2$ emission in exhaust gas according as increment of the $SO_2$ standard gas had almost the same ratio compared with $SO_2$ rate in mixture inlet gas. Furthermore, the $N_2O$ element in exhaust gas was formed as $SO_2$ mixture in intake gas because increment of $SO_2$ flow rate in intake gas increased $N_2O$ emission. Hence, diesel fuels included sulfur compounds were combined into $SO_2$ in combustion, and $N_2O$ in exhaust gas should be generated to react with NO and $SO_2$ which exist in a combustion chamber.

Herbicidal Activities of Dinitroaniline Compounds in Turfgrass (Dinitroaniline계(系) 제초제(除草劑)의 잔디밭에서의 작용특성(作用特性))

  • Lee, Y.D.;Kim, S.J.;Kim, K.W.;Kim, K.U.
    • Korean Journal of Weed Science
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    • v.14 no.4
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    • pp.265-271
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    • 1994
  • This study was conducted to determine the herbicidal activity, persistance, downward movement and effect on bentgrass of 7 dinitroaniline herbicides such as benefin [N-butyl-N-ethyl-2,6-dinitro-4-(trifluoromethyl) benzenamine], beslogine [N,N-dibutyl-2,6-dinitro-4-trifluoromethylaniline], prodiamine [2,4-dinitro-$N^3$,$N^3$-dipropyl-6-(trifluoromethyl)-1,3-benzenediamine], pendimethalin [N-(1-ethylpropyl)-3,4-dimethyl-2,6-dinitrobenzenamine], trifluralin [2,6-dinitro-N,N-dipropyl-4-(trifluoromethyl) benzenamine], ethalfluralin [N-ethyl-N-(2-methyl-2-propenyl)-2,6-dinitro-4-(trifluoromethyl) benzenamine], and oryzalin [4-(diprop-ylamino)-3,5-dinitrobenzene-sulfonamide) together with bensulide [O,O-bis(1-methylethyl) S-[2-[(phenyl-sulfonyl) amino]ethyl]phosphorodithioate] and siduron [N-(2-methylcyclohexyl)-N'-phenylurea) as the control. In addition, distribution of pendimethalin and benefin into bentgrass was also determined. Prodiamine, benefin, and pendimethalin at the 1/16 dose of the recommended rate showed very high herbicidal activity($LD_{90}$) on Digitaria sanguinalis, but ethalfluralin and bensulide showed $LD_{90}$ at the 1/4 dose of the recommended rate, showing difference in herbicidal activities among dinitroaniline herbicides. All the herbicides except for pendimethalin had the lower herbicidal activity in sandy soil than that of clay-loam soil. Benefin, beslogine, prodiamine, oryzalin, bensulide and siduron persisted in the soil for about 50 days, but pendimethalin persisted in the soil for about 35 days, and trifluralin and ethalfluralin for about 25 days. Ethalfluralin, oryzalin and bensulide were the most mobile(downward movement) of the 9 herbicides studied. Less mobility was observed in the turfgrass condition than that of the bare soil. Beslogine bensulide prodiamine and benefin had no injury effect on bentgrass(Agrastis atolonifera L., penncross creeping bent grass). However, herbicides like oryzalin, trifluralin and pendimethalin reduced the dry weight of bentgrass by 12%, 30% and 40%, respectively. No significant difference in distribution of pendimethalin and benefin into inner part of leaves, surface and wax layer of bentgrass was observed, and thus it seems that different phytotoxic effect between pendimethalin and benefin may be attributed to different metabolism and mode of action.

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Effect of LED mixed light conditions on the glucosinolate pathway in brassica rapa (배추 유묘의 글루코시놀레이트 합성 기작에 미치는 LED 혼합광의 효과)

  • Moon, Junghyun;Jeong, Mi Jeong;Lee, Soo In;Lee, Jun Gu;Hwang, Hyunseung;Yu, Jaewoong;Kim, Yong-Rok;Park, Se Won;Kim, Jin A
    • Journal of Plant Biotechnology
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    • v.42 no.3
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    • pp.245-256
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    • 2015
  • In the agricultural industries, LEDs are used as supplementary, as well as main lighting sources in closed cultivation systems. In cultivation using artificial light sources, various light qualities have been tried to supplement fluorescent lamps to promote plant growth and metabolism. Microarray analysis of Brassica rapa seedlings under blue and fluorescent mixed with blue light conditions identified changes in three genes of the glucosinolate pathway. This attracted attention as functional materials highly expressed 3.6-4.6 fold under latter condition. We selected four more genes of the glucosinolate pathway from the Brassica database and tested their expression changes under fluorescent light mixed with red, green, and blue, respectively. Some genes increased expression under red and blue mixed conditions. The Bra026058, Bra015379, and Bra021429; the orthologous genes of CYP79F1, ST5a, and FMOGS-OX1 in Arabidopsis, are highly expressed in Brassica rapa under fluorescent mixed with blue light conditions. Further, Bra029355, Bra034180, Bra024634, and Bra022448; the orthologous genes of MAM1, AOP3, UGT74B1, and BCAT4 in Arabidopsis, are highly expressed in Brassica rapa under fluorescent mixed with red light conditions. The various light conditions had unique effects on the varieties of Brassica, resulting in differences in glucosinolate synthesis. However, in some varieties, glucosinolate synthesis increased under mixed blue light conditions. These results will help to construct artificial light facilities, which increase functional crops production.

Effect of Animal Organic Soil Amendment on Growth of Korean Lawngrass and Kentucky Bluegrass (동물성 유기질 개량재가 들잔디 및 캔터키 블루그래스 잔디생육에 미치는 효과)

  • Koh, Seuk-Koo;Tae, Hyun-Sook;Ryu, Chang-Hyun
    • Asian Journal of Turfgrass Science
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    • v.20 no.1
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    • pp.33-40
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    • 2006
  • Many soil amendments have been used nowadays to improve physical and chmical condition of turf soil, which might ultimately optimize turfgrass growth in golf courses. This study was carried out to Investigate the effects of new organic soil amendment containing pig excreta 50% and sawdust 50% on growth of zoysiagrass (Zoysia japonica L.) and kentucky bluegrass (Poa pratensis L.) in greenhouse. Three applicable treatments with soil mixtures of 10, 20, and 30% (v/v) animal organic soil amendment (AOSA) with sand, were tested for chemical property, physical property, visual quality and root length of zoysiagrass and Kentucky bluegrass. As results, application of $10{\sim}30%$ AOSA mixtures were proper to grow turfgrass in soil nutrition. Especially, the treatment with 20% AOSA mixtures showed 0.7% in organic matter, which meets to green standard of USGA. Also, 30% AOSA mixtures was 1.1% in organic matter, which might be desirable for zoysiagrass-planted golf courses in Korea. It was turned out that addition of AOSA decreased the hydraulic conductivity in soil physical property Because the sand possess high hydraulic conductivity, it is recommended to combine $10{\sim}30%$ AOSA with sand in order to sustain soil balance. The treatment with $10{\sim}30%$ AOSA noticeably increased visual quality of both zoysiagras and Kentucky bluegrass during 90 days. However, treatments with either 20% or 30% AOSA were effective to develop root length of zoysiagrass but treatments with 20% AOSA were more effective than that of 30% AOSA mixtures to promote root length of Kentucky bluegrass at 60 days. In conclusion, considering all vital factors such as visible quality, root growth, organic matter content, and economical efficiency, was taken, it is recommended that a $20{\sim}30%$ mixture of AOSA with sand is good for the growth of zoysiagrass and 20% mixture for Kentucky bluegrass.

Simultaneous Treatment of Carbon Dioxide and Ammonia by Microalgal Culture (조류배양을 통한 이산화탄소 및 암모니아의 동시처리)

  • ;;Bohumil Volesky
    • KSBB Journal
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    • v.14 no.3
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    • pp.328-336
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    • 1999
  • A green microalga, Chlorella vulgaris UTX 259, was cultivated in a bench-scale raceway pond. During the culture, 15%(v/v) $CO_2$ was supplied and industrial wastewater discharged from a steel-making plant was used as a culture medium. In a small scale culture bottle, the microalga grew up to 1.8 g $dm^{-3}$ of cell concentration and ammonia was completely removed from the wastewater with an yield coefficient of 25.7 g dry cell weight $g^{-1}\;NH_3-N$. During the bottle-culture, microalga was dominant over heterotrophic microorganisms in the culture medium. Therefore, the amount of carbon dioxide fixation could be estimated from the change of dry cell weight. In a semi-continuous operation of raceway pond with intermittent lighting (12 h light and 12 h dark), increase of dilution rate resulted in increase of the ammonia removal rate as well as the $CO_2$ fixation rate but the ammonia removal efficiency decreased. Ammonia was not completely removed from the medium (wastewater) of raceway pond which was operated in a batch mode under a light intensity up to 20 klux. The incomplete removal of ammonia was believed due to insufficient light supply. A mathematical model, capable of predicting experimental data, was developed in order to simulate the performance of the raceway pond under the light intensity of sun during a bright daytime. Simulation results showed that the rates of $CO_2$ fixation and ammonia removal could be enhanced by increasing light intensity. According to the simulation, 80 mg $dm^{-3}$ of ammonia in the medium could be completely removed if the light intensity was over 60 klux with a continuous lighting. Under the optimal operating condition determined by the simulation, the rates of carbon dioxide fixation and ammonia removal in the outdoor operation of raceway pond were estimated as high as $24.7 g m^{-2} day^{-1}$ and $0.52 g NH_3-N m^{-2} day^{-1}$, respectively.

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한국농촌의 식품금기에 관한 연구

  • 모수미
    • Journal of the Korean Home Economics Association
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    • v.5 no.1
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    • pp.733-739
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    • 1966
  • A 371 agricultural households from 26 different communities in South Korea was subjected on a study of food taboos in January of 1966. To the pregnant women, those to whom a high protein diet is particurally important, as many as 14 different kinds of foods, mostly portein rich foods, were avoided to eat. It is believed that if duck is eaten while pregnant her baby may walk like a duck in later life. Some mother have a strong aversion to the rabbit meat that her unborn baby must be a harelip. It is feared to eat chicken, shark or carp by the pregnant mother for her baby may get a gooseflesh appearance, or fish scale-like skin in later life. It is thought that if mother eats soup made of meat borns, especially chicken bones, a disfigured baby may be born. Some area informed that if mother eats crab meat her future baby will always bubble. To the child-bearing mothers 13 different kinds of foods were avoided to eat. Some believe that if raddish kimchi, soybean curd, squash are eaten while dilivery that mother may get dental decay or to lose all her teeth. Other think that highly spiced raddish kimchi cause delivery difficult. To the lactating mothers 7 different items of foods were not recommended to eat. It is a common belief that eating green vegetables, especially fresh lettuce, are restricted that her baby may stool greenish. It is said that eating ginsen-chicken soup, or ginsen tea during lactating reduces breast milk secretion. To the weaning babies 7 different kinds of foods were prohibited to fee. Eggs are not eaten because mothers think her babies will start to talk very late. Eight different items of foods in cases of gastro-intestinal diseases, 5 items for liver disease, 7 items for high blood pressure as well as for paralysis were respectively restricted. It is said that meats including pork, beef, and chicken are neither desirable for the patients of high blood pressure nor those of paralysis. To the measles children 10 varieties of foods were restricted. Especially soybean products and meats were not encouraged to use for avoiding asecond attack of measles. For the common cold 8 different kinds of foods were aversed and men think that eating of soup of undria delays a recovery. For the tuberculosis 4 kinds of foods were prohibited to eat. It is said that wine, red pepper and ginsen will stimulate lung bleeding. Many mothers had a strong aversion to fermented shrimp and fish in case of style. and 5 different items of foods were restricted. In case of menstration not so many foods were restricted as other cases, but meat soup is not eaten in this condition in some areas. Majority of food taboos in Korean villages are neither based on tribal nor religious factors. But no one knows how, since what ages, from where, these food taboos have been transmitted and spread over the country. This survey found a great variety of food taboos, aversions, traditional beliefs and prohibitions latent unknown reseasons, or non-scientific conceptions, or completely different ideas from the modern medical aspect, or somewhat fallacious and superstitious beliefs. For the vascular disease contrasting approach were found between modern the oritical therapy and popular remedy among the rural populations who largely depend on the eastern medication. Further scientific study on either side should be done to lead the patient proper way. Many restricted foods such as rabbit, duck, chicken and fish are best resources of protein rich foods which are available in the village. Emphasis should be laid upon breaking down fallacious and supersititious food taboos through the extended nutrition education activities in order to improve food habit and good eating pattern for healthier and stronger generations of Korea.

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고려왕조대 고려와 교류하였던 제국과 고려의 복식제도에 관한 연구

  • 임명미
    • Journal of the Korean Society of Costume
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    • v.20
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    • pp.31-47
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    • 1993
  • 1. The relationship between Korea and Buk-Song had maintained for 164 years(964 1126 A.D). The period of relationship was from KwangJong Year 13(4years after establishing Buk-Song), Song Tae-Cho 1 year, to HeumJong Cheong Dang 1st year(InJong 4years in Koran). Author divides into three periodic terms, and remarkable diplomatic facts are as follows. 1) KwangJong year 13(963 A.D) SungJong year 13(994 A.D) : Normal relations, Song needed Korea's armed support. 2) MokJong year 6(1003 A.D) HyunJong year 9(1018 A.D) : Not steady relations and broke up, by MunJong year 26, Dang requested to resume the diplomatic relations. 3) MunJong year 25(1017 A.D) InJong 4(1126 A.D) : Song utilized Korea as a back supporter, but Song destructed by Keum. 2. Korea was donated knightage without offcial clothing by BukSong 10 times(KwangJong year 13 SungJong year 11). However during 164 years. Song presented some clothings Korea friendly. 3. Even though Korea cound not continue the steady diplomatic relations, Korea had been influenced the social systems including cloth-ing systems by Dang. Song dynasty. 4. The author studys historical materials which show that TongilSh-Shinra adapted social systems of Dang dynasty including clothing systems, which was succeeded to Korea for 200 years. Details are as follows ; 1) Original clothing color-systems which were Ja(purpil), Cheong(blue), Hwang(yellow), Pi, called 4-clored-system, of Tongil-Shinra, was suceeded to Korea, Above mentioned clothing systems of three countries of Korean peninsula. 2) When Korea unified the certificate of Pisam holders were superior from those of Tongil-Shinra and Hoo-Bakjae. There two classes used same seried-color 'ja, (Dan, Pi), Cheong(blue), Hwang(yellow)', or 'ja, (Dan, Pi), Cheong' and lasted to KwangJong year10 as a of-ficial clothing. 3) KwangJong year 7, according to the three colored official clothing system of Hooju, accepted Hooju's KwangJong year 11, that shifted 'Ja, (Dan, Pi), Cheong, Hwang', or, Ja, (Dan, Pi) Cheong', to 'Ja, Dan, Pi, Rok(green)'. 4) The clothing systems which are ja, (Dan, Pi), Rok which established KwangJong year 11 shifted to Song's, Ja, Ju(orange), Rok, Cheong, which had happened SungJong year 14 to MokJong 1st year. 5) 4-colored systems ('Ja, Pi, Rok, Cheong (distictable : sky blue, ocean blue)' shifted to 3 colored system which established Song ShingJong 1st year, which succeeded to Nam-Song and Keum. 5. The relationship between Korea and Yo had maintained for 207 years(918 1125 A.D). The period of relationship was from TaeJo 1st year to InJong year 3. 6. Yo, and Korea were called for king(15 times), prince(7 times). 7. Korea was donated knightage by Yo. The time when HyunJong year 13, Yo donated official clothing. From that time had used to do. The author divides into three periodic terms and discrives the shifting the formal clothing systems. Details were as follows ; 1) HyunJong year 13 MunJong year 8 : Even donating clothing systems from Yo had maintained for 35 years, Yeo, Song, Yo, three countries had not have formal cloth-ing, because they had been on the strug-gling. So that Korea had followed the same way of informal clothing. 2) MunJong year 918 : Yo donated the formal clothing to Korea for the King. Diplomatic condition was in the control, so that whole three countries used formal clothing. 3) MunJong year 19 YeaJong year 3 : Korea was donated 'Kuryumyun Kujangbokje', which became the formal clothings vs China.

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A study on Perfume case (향(香) 집에 관한연구)

  • 이선재
    • Journal of the Korean Society of Costume
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    • v.33
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    • pp.117-142
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    • 1997
  • This study is on perfume case that is one of a great number of ornaments which was designed by out ancestors. We had developed the tradition and the history of perfume case bag fan-weight etc. These have the same function as the present perfume. case. There were basket-shaped perfume cases which were the smellest one among the personal girdle ornaments in the silla era. The various patterned perfume case were made of gold metal coral platinum or green jadeite etc. In the single-crop trinkets a embroidered perfume bag with the gold and silver thread whose forms perfectly match their functions appeared during the Yi Dynasty. There was also a perfume bag which was one of the daily necessities. A precious "jul perfume" was carried by noble women. A fan-weight perfume bag was attached to the fan to emphasize the intrinsic beauty of utility and function. It is necessary to know the function of prefume case. As perfume case is weared on the clothes it was given more decorative effects as well as the function of medicinal amulet with a sweet smell. Therefore it is very important for us to study perfume case that has various function as an ornament. So The purpose of this study is to investigate the practical and decorative side of perfume case with the general examines of perfume finding how to practice use through our life. The results were as follows; 1. The first use of perfume is perfume through smoke which is for ceremony of religion It removes human body odor by degrees and spreads a sweet odor. Also the materials for making perfume of early age is aromatic plants which will be used flour-made flowers stems. As the materials for making perfume use is increasing today we can invent alcohol perfume today 2. Our country the custom of perfume-used is wide. Among them men's perfume-used was very special phenomenon. For example men were wearing perfume bag in the Silla era. Because perfume represented wealth and noble in those days. They shew off social position personality through perfume-used. 3. One of early religion ceremony article there was the perfume. And perfume case was means for containing perfume. Gradually the perfume case was used widly as increasing needs of perfume in human life. 4. In the middle period of 'Koryo' Dynasty perfume cases had a close relationship with clothes but after Mongolian has been attacked 'Koryo' there were changes in wearing clothes therefore the position of perfume cases were transfered to coat string that was the origin of decoration style that they began. That is to say the perfume case has been influenced the position of perfume case shapes with changing of fashion. 5. The perfume case has been made manifest various function as an ornament. In the practical side First medical-perfume in perfume case has been played an important role in first-aid medicine in critical condition. Second it was amulet for self protection. That is the shape pattern color materials perfume of the perfume case was represented the amuletive nature. Third it was used as substitute article of perfume. Modern women use liquid-perfume as our ancestors used perfume case bag or jul perfume As started above. Also In the decorative side the perfume case has a beautiful formative arts by itself as well as a close relationship with clothes. That well as a close relationship with clothes. That is when the perfume case is worn on the clothes costume is showed aesthetices. That is the materials shapes color pattern of the perfume case we can see the visual beauty also the materials colors embroidered pattern knots tassel that are used the perfume case are increased the decorative beauty of costume. Sixth the symbol in pattern of the pattern case is shown ancetor's wealth and rank health longevity immortality many-born-boy in those days. Today the perfume case is not used with changing of costume by degrees, Accordingly I hope that the result of this study is an influened in devlopment of the perfume case design with matching the modern fashion.

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Development and Preliminary Test of a Prototype Program to Recommend Nitrogen Topdressing Rate Using Color Digital Camera Image Analysis at Panicle Initiation Stage of Rice (디지털 카메라 칼라영상 분석을 이용한 벼 질소 수비량 추천 원시 프로그램의 개발과 예비 적용성 검토)

  • Chi, Jeong-Hyun;Lee, Jae-Hong;Choi, Byoung-Rourl;Han, Sang-Wook;Kim, Soon-Jae;Park, Kyeong-Yeol;Lee, Kyu-Jong;Lee, Byun-Woo
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.55 no.4
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    • pp.312-318
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    • 2010
  • This study was carried out to develop and test a prototype program that recommends the nitrogen topdressing rate using the color digital camera image taken from rice field at panicle initiation stage (PIS). This program comprises four models to estimate shoot N content (PNup) by color digital image analysis, shoot N accumulation from PIS to maturity (PHNup), yield, and protein content of rice. The models were formulated using data set from N rate experiments in 2008. PNup was found to be estimated by non-linear regression model using canopy cover and normalized green values calculated from color digital image analysis as predictor variables. PHNup could be predicted by quadratic regression model from PNup and N fertilization rate at panicle initiation stage with $R^2$ of 0.923. Yield and protein content of rice could also be predicted by quadratic regression models using PNup and PHNup as predictor variables with $R^2$ of 0.859 and 0.804, respectively. The performance of the program integrating the above models to recommend N topdressing rate at PIS was field-tested in 2009. N topdressing rate prescribed for the target protein content of 6.0% by the program were lower by about 30% compared to the fixed rate of 30% that is recommended conventionally as the split application rate of N fertilizer at PIS, while rice yield in the plots top-dressed with the prescribed N rate were not different from those of the plots top-dressed with the fixed N rates of 30% and showed a little lower or similar protein content of rice as well. And coefficients of variation in rice yield and quality parameters were reduced substantially by the prescribed N topdressing. These results indicate that the N rate recommendation using the analysis of color digital camera image is promising to be applied for precise management of N fertilization. However, for the universal and practical application the component models of the program are needed to be improved so as to be applicable to the diverse edaphic and climatic condition.

Seasoning of Commercial Wood Using Solar Energy (태양에너지를 이용한 유용목재의 건조)

  • Jung, Hee-Suk;Lee, Hyoung-Woo;Lee, Nam-Ho;Lee, Sang-Bong
    • Journal of the Korean Wood Science and Technology
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    • v.16 no.4
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    • pp.10-39
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    • 1988
  • This study investigated the temperatures and relative humidities in the semi-greenhouse type solar dryer with a black rock-bed heat storage and without heat storage and outdoor temperature and relative humidity at 9 a.m. and 2 p.m.. A comparison was made of the drying rates, final moisture contents, moisture content distributions, casehardening stresses, drying defects, volumetric shrinkage of dried lumber for solar- and air-drying from the green condition of mixtures of Douglas-fir, lauan, taun, oak and sycamore 25mm- and 50 mm-thick lumber during the same period for four seasons, and heat efficiencies for solar dryer with and without the heat storage for saving of heat energy and the cost of lumber drying using the solar energy. The results from this study were summarized as follows: I. The mean weekly temperatures in the solar dryers were 3 to $6^{\circ}C$ at 9 a.m. and 9 to $13^{\circ}C$ at 2 p.m. higher than mean outdoor temperature during all the drying period. 2. The mean weekly relative humidities in the solar dryers were about 1 to 19% at 9 a.m. higher than the outdoor relative humidity. and the difference between indoor and outdoor relative humidity in the morning was greater than in the afternoon. 3. The temperatures and relative humidities in the solar dryer with and without the heat storage were nearly same. 4. The overall solar insolation during the spring months was highest and then was greater in the order of summer, atumm, and winter month. S. The initial rate of solar drying was more rapid than that of air drying. As moisture content decreased, solar drying rate became more rapid than that of air drying. The rates of solar drying with and without heat storage were nearly same. The drying rate of Douglas-fir was fastest and then faster in the order of sycamore, lauan, taun and oak. and the faster drying rate of species, the smaller differences of drying rates between thicknesses of lumber. The drying rates were fastest in the summer and slowest in the winter. The rates of solar drying during the spring were more slowly in the early stage and faster in the later stage than those during the autumn. 6. The final moisture contents were above 15% for 25mm-thick air dried and about 10% for solar dried lumber, but the mean final MCs for 50mm-thick lumber were much higher than those of thin lumber. The differences of final MC between upper and lower course of pile for solar drying were greater than those of pile for air drying. The differences of moisture content between the shell and the core of air dried lumbers were greater than those of solar dried lumber, smallest in the drying during summer and greatest in the drying during winter among seasons. 7. Casehardening stresses of 25mm- and 50mm-thick dried lumber were slight, casehardening stress of solar dried lumber was severer than that of air dried lumber and was similar between solar dried lumber with and without heat storage, Casehardening stresses of lumber dried during spring were slightest and then slighter in the order of summer, autumn, and winter. Casehardening stresses of Douglas -fir, sycamore and lauan were slight, comparing with those of taun and oak. 8. Maximum initial checks of 25mm-thick lumber occurred above and below fiber saturation point and those of 50mm-thick lumber occurred in the higher moisture content than thin lumber. As the moisture content decreased, most of checks were closed and didn't show distinct difference of the degree of checks among drying methods. The degree of checks were very slight in case of Douglas-fir and lauan, and severe in case of taun and oak. The degree of checks for 50mm-thick lumber were severer than those for 25mm-thick lumber. 9. The degree of warpage showed severe in case of oak and sycamore lumber, but no warping was found in case of Douglas-fir, lauan and taun. 10. The volumetric shrinkages of taun and oak were large and medium in case of Douglas-fir, lauan and sycamore. 11. Heat efficiencies of solar dryer with heat storage were 6.9% during spring, 7.7% during summer, 12.1% during autumn and 4.1% during winter season. Heat efficiency of solar dryer with heat storage was slightly greater than that of without heat storage. As moisture content of lumber decreased, heat efficiency decreased.

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