• Title/Summary/Keyword: growing condition

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Effects of microstructures of the sintered rod on the single crystal grown by the floating zone method (Floating zone법에 의한 결정성장시 소결봉의 미세구조에 의한 영향)

  • 신재혁;오근호
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.5 no.3
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    • pp.250-260
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    • 1995
  • In general, a sintered rod is used as a feed in the growth of crystals by the floating zone(FZ) method. The sintering condition of the feed rod affected the stability of molten zone because it influenced the interface shape between the feed and the melt during the crystal growth. In this study, rutile and ruby crystals were chosen as samples to analyze the effect of the microstructures of the feed rods. In sintering of the feed rod for the growth of rutile and ruby single crystals, the difference of grain size between the inner and the outer region of the feed rod increased with the sintering temperature and dwelling time. As a result, it altered melting behavior of the feed. The uniform grain size of the sintered rod was necessary for the optimum growing condition of crystals. The effect of pores in the feed rod was not a dominant factor to grow crystals by the FZ method, which was confirmed by growing crystals with nonsinterd rods as feeds.

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Social Environment Research of Capitalism for the Private Security Development (민간경호경비의 발전에 대한 자본주의의 사회환경적 해석)

  • Kim, Chang-Ho;Gong, Bae-Wan
    • Korean Security Journal
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    • no.7
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    • pp.125-154
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    • 2004
  • Capitalism is based on a material desire of the human being. the social control of capital value and the management of capital ability reflects the actual condition of the capitalism well. The unconstrained growing and the expansion of capitalism, it finally lost social meaning and an importance of human being element and the safety of the civilian life, began to threat the security of citizen by forming over the material center structure of society. Improving human life quality and material richness on their life leads positive factor of capitalism whereas is causing several crimes through the society which is being threatened around a human being life for a negative factor of the capitalism. Therefore capitalistic social system has offered both a positive factor 'growing' and 'richness' and that of a negative 'structural poverty' and 'lack of security' and they have been remaining the assignment of capitalism 'poverty' and 'security' by settlement in the society for a extremely phenomenon of both sides. The objective of this research is to build its study theory and establish its causal relation by illuminating for the social environment of capitalism for a private guard or a development background of the civil security contributing for citizen security, as well as gets the clue of the development possibility of the civil guard and escort field and the development of capitalism. In Korea because their recognition of the study approach and the social safety for social security control function is still staying first step and our daily life is annoying from various threat of the society, many studies and the realistic necessity of experience related with social security is being studied. In addition, The development possibility of the civil guard and defense at the civil field which will be keep the social security has a wide position but its study approach and realistic comprehension is still in insufficient condition. Consequently, this research is started to grasp the security of civil fiend and to grope a development possibility through the research of capitalism.

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증발억제법에 의한 수온 및 지온상승효과에 관한 연구

  • 김광식
    • Water for future
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    • v.5 no.2
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    • pp.6-16
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    • 1972
  • It has been well studied and known that the yields from the rice fields irrigated by the cold water such as the water directly flowing in from mountain valleies, underground water and subground water are largely influenced by the water temperature. However, the best method of raising water temperature has not yet been established. This is because there are some essentially difficult problems associated. When we examine the effects of $1^{\circ}C$ rise in the water temperature under natural condition on rice growing, the necessity of this line of study is verified. The results of Mihara's study show that rice bears its fruits at the water temperature above $19^{\circ}C$ and the difference of $1^{\circ}C$ in the range of $19^{\circ}C$ to $22^{\circ}C$ can produce the 20% of difference in yields. Because of these facts, most farmers have made use of water temperature raising ponds, zigzag waterways and shelter belts. But the most important factor in raising water temperature has been found to be the heat loss due to evaporation. Recently, a good deal of experiment on raising water temperature and soil temperature by reducing the evaporation are being carried out all over the world. The reduction of evaporation does not only reduce heat loss, from the surface but also reduce the loss of water. Present study is aimed to determine the efficiency of different chemicals by which monomolecular films are formed over different surfaces such as water surface, soil surface and the surface of plant leaves with a purpose of preventing the transpiration, and aimed to observe the effects of the temperature rise and its influence on growing state as well as the durability of the plants under drought condition.

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Biodegradation of Pentachlorophenol by Various White Rot Fungi (수질분해균(水質分解菌)에 의한 Pentachlorophenol의 미생물분해(微生物分解))

  • Choi, In-Gyu;Ahn, Sye-Hee
    • Journal of the Korean Wood Science and Technology
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    • v.26 no.3
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    • pp.53-62
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    • 1998
  • In this research, 7 species of white rot fungi were used for determining the resistance against pentachlorophenol (PCP). Three fungi with good PCP resistance were selected for evaluating the biodegradability, and biodegradation mechanism by HPLC and GC/MS spectrometry. Among 7 fungi, there were significant differences on PCP resistance on 4 different PCP concentrations. In the concentrations of 50 and 100ppm ($\mu$g of PCP per g of 2% malt extract agar), most fungi were easily able to grow, and well suited to newly PCP-added condition, but in that of more than 250ppm, the mycelia growths of Ganoderma lucidum 20435, G. lucidum 20432, Pleurotus ostreatus, and Daldinia concentrica were significantly inhibited or even stopped by the addition of PCP to the culture. However, Trametes versicolor, Phanerochaete chrysosporium, and Inonotus cuticularis still kept growing at 250ppm, indicating the potential utilization of wood rot fungi to high concentrated PCP biodegradation. Particularly, P. chrysosporium even showed very rapid growth rate at more than 500ppm of PCP concentration. Three selected fungi based on the above results showed an excellent biodegradability against PCP. P. chrysosporium degraded PCP up to 84% on the first day of incubation, and during 7 days, most of added PCP were degraded. T. versicolor also showed more than 90% of biodegradability at 7th day, and even though the initial stage of degradation was very slow, I. cuticularis has been approached to 90% at 21 st day after incubation with dense growing pattern of mycelia. Therefore, the PCP biodegradability was definitely dependent on the rapid suitability of fungi to newly PCP-added condition. In addition, the PCP biodegradation by filtrates of P. chrysosporium, T. versicolor, and I. cuticularis was very minimal or limited, suggesting that the extracellular enzyme system may be not so significantly related to the PCP biodegradation. Among the biodegradation metabolites of PCP, the most abundant one was pentachloroanisole which resulted in a little weaker toxicity than PCP, and others were tetrachlorophenol, tetrachloro-hydroquinone, benzoic acid, and salicylic acid, suggesting that PCP may be biodegraded by several sequential reactions such as methylation, radical-induced oxidation, dechlorination, and hydroxylation.

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A Divice of Development and A Social Dominant Factor of the Private Security (민간경비의 사회적 성장요인과 발전방안)

  • Gong, Bae-Wan
    • Journal of the Society of Disaster Information
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    • v.1 no.1
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    • pp.27-42
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    • 2005
  • Recently the demand for civil security and security guards shows rapid growth. However the supply and training system have some limitations. Educational and training systems for civil body and security guards are in the basic level and private organizations trained the professional work force. So this paper is showing what a social dominant factor and a divice of development of the private security. Capitalism is based on a material desire of the human being. the social control of capital value and the management of capital ability reflects the actual condition of the capitalism well. The unconstrained growing and the expansion of capitalism, it finally lost social meaning and an importance of human being element and the safety of the civilian life, began to threat the security of citizen by forming over the material center structure of society. Improving human life quality and material richness on their life leads positive factor of capitalism whereas is causing several crimes through the society which is being threatened around a human being life for a negative factor of the capitalism. Therefore capitalistic social system has offered both a positive factor 'growing' and 'richness' and that of a negative 'structural poverty' and 'lack of security' and they have been remaining the assignment of capitalism 'poverty' and 'security' by settlement in the society for a extremely phenomenon of both sides. In Korea because their recognition of the study approach and the social safety for social security control function is still staying first step and our daily life is annoying from various threat of the society. many studies and the realistic necessity of experience related with social security is being studied. In addition. The development possibility of the civil guard and defense at the civil field which will be keep the social security has a wide position but its study approach and realistic comprehension is still in insufficient condition.

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Variability of Soil Water Content, Temperature, and Electrical Conductivity in Strawberry and Tomato Greenhouses in Winter

  • Ryu, Dong-Ki;Ryu, Myong-Jin;Chung, Sun-Ok;Hur, Seung-Oh;Hong, Soon-Jung;Sung, Je-Hoon;Kim, Hak-Hun
    • Journal of Biosystems Engineering
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    • v.39 no.1
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    • pp.39-46
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    • 2014
  • Purpose: Monitoring and control of environmental condition is highly important for optimum control of the conditions, especially in greenhouses and plant factories, and the condition is not uniform within the facility. Objectives of the study were to investigate variability in soil water content and to provide information useful for better irrigation control. Methods: Experiments were conducted in a strawberry-growing greenhouse (greenhouse 1) and a cherry tomato-growing greenhouse (greenhouse 2) in winter. Soil water content, electrical conductivity (EC), and temperature were measured over the entire area, at different distances from an irrigation pump, and on ridge and furrow areas. Results: When measured over the entire greenhouse area, soil water content decreased and temperature and electrical conductivity increased over time from morning to afternoon after irrigation. Water content decreased by distance from the irrigation pump up to 70 m and increased after that, and temperature showed an inverse pattern. Soil water contents on the ridge were lower than those on the furrow, and the differences were 10.2~18.4%, indicating considerable variability. The lowest EC were observed on the furrow and highest values were observed on the ridge. Soil water contents were less and temperature levels were greater at the window side than in the center locations. Conclusions: Selection of number and location of soil water content sensor would be the first step for better water content monitoring and irrigation control. Results of the study would provide basic data useful for optimum sensor location and control for underground greenhouse environment.

Studies on the Grassland Development in the Forest XII. Effect of nitrogen fertilization on nitrate nitrogen concentration and water soluble carbohydrate content of grasses by growing season and growth stage under shading condition (임간초지 개발에 관한 연구 XII. 차광조건하에서 질소시비수준이 계절별 , 생육시기별 목초의 질산태질소함량과 수용성탄수화물함량에 미치는 영향)

  • Seo, Sung
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.12 no.2
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    • pp.104-110
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    • 1992
  • This experiment was carried out to determine the effects of nitrogen(N) fertilization levels(0. 120, 240 and 360 kg/ha/y) on seasonal nitrate nitrogen($NO_3$-N) concentration and water soluble carbohydrate (WSC) content of grasses grown under shading condition. The plants were sampled on 7. 14, 21, 28 and 35 days after harvesting in spring(May), summer(July) and autumn(September), 1988. respectively. Shading degree was controlled artificially ca. 45-50%, and each annual level of N was distributed 5 times equally. The $NO_3$-N concentration of grasses was very low(0.064 %) in spring, high in summer(O.l98 %) and autumn(0.234%), and NO,-N was slightly decreased with growing of grasses. Also the NO,-N concentration of grasses was increased significantly with increasing level of N. In spring, the $NO_3$-N of grasses was very safety(less than 0.1 %), regardless of plant height and N level. In summer and autumn, however, plant heights of below 40 cm(summer) and 44 cm(autumn), and N levels of over 210 kg(summer) and 140 kg(autumn) were over toxic level to animals, respectively. The WSC content of grasses was slightly decreased with grass growth. and significantly decreased with high level of N. From the above results, it is suggested that 200 kg/ha of N in this experiment is effective for forage quality. Also a little more amount of N(50-70kgltimes) in spring. and low level of N(20-30 kgltimes) in summer and autumn season may be desirable on woodland posture.

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Intercropping in Rubber Plantation Ontology for a Decision Support System

  • Phoksawat, Kornkanok;Mahmuddin, Massudi;Ta'a, Azman
    • Journal of Information Science Theory and Practice
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    • v.7 no.4
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    • pp.56-64
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    • 2019
  • Planting intercropping in rubber plantations is another alternative for generating more income for farmers. However, farmers still lack the knowledge of choosing plants. In addition, information for decision making comes from many sources and is knowledge accumulated by the expert. Therefore, this research aims to create a decision support system for growing rubber trees for individual farmers. It aims to get the highest income and the lowest cost by using semantic web technology so that farmers can access knowledge at all times and reduce the risk of growing crops, and also support the decision supporting system (DSS) to be more intelligent. The integrated intercropping ontology and rule are a part of the decision-making process for selecting plants that is suitable for individual rubber plots. A list of suitable plants is important for decision variables in the allocation of planting areas for each type of plant for multiple purposes. This article presents designing and developing the intercropping ontology for DSS which defines a class based on the principle of intercropping in rubber plantations. It is grouped according to the characteristics and condition of the area of the farmer as a concept of the rubber plantation. It consists of the age of rubber tree, spacing between rows of rubber trees, and water sources for use in agriculture and soil group, including slope, drainage, depth of soil, etc. The use of ontology for recommended plants suitable for individual farmers makes a contribution to the knowledge management field. Besides being useful in DSS by offering options with accuracy, it also reduces the complexity of the problem by reducing decision variables and condition variables in the multi-objective optimization model of DSS.

Effects of Various Anions on Absorption and Toxicity of Lead in Plants (식물체의 연(Pb) 흡수 및 유해성에 미치는 음이온의 영향)

  • 성민웅
    • Journal of Plant Biology
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    • v.20 no.1
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    • pp.7-14
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    • 1977
  • The seeds of bean(Glycine max M.) and corn(Zea mays L.) soaked in 5000ppm lead solution for 24 hours were sowed in the flowerpots being placed sandy-clay soil under the field condition. The fixed concentrations of various anions and 2000 ppm lead were supplied alternately in the sandy-clay soi of the flowerpots at two days interval from May to July in 1976. After the plants were harvested prior to the flowering stage, the lead contents of plnat and soil were analyzed by atomic absorption spectrophotometer. The lead contents absorbed by the plant roots showed the highest in an weak acid soil of the best suitable condition of plant growth. The absorption of lead by the plant roots was inhibited by the various anions, especially divalent anions of the soil. Some phosphate anions inhibited lead absorption more than otehr various anions in the soil. The more various anions were in the soil, the more plants could be protected from the lead toxicity. In the case of lead supply in the soil, 99.5% of lead was accumulated in the upper layer of the soil(0-10cm), and 0.5% of lead accumulated in the lower layer (10-20cm). Therefore, the yellow-brown and white symptoms on the leaves and the inhibition of root growth by lead toxicity was increased in the early stage of the germination, however decreased in accordance with the progress of the growing stage becuase of the root growth toward beneath the lower layer of the soil. In spite of the contents of 3773ppm lead in the soil, the symptoms of lead toxicity was not found in the grown plants. At that time the lead contents of the plants absorbed from the soil were minimum 0.78ppm and maximum 3.64ppm through the growing stage.

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Estimation of Optimum Period for Spring Cultivation of 'Chunkwang' Chinese Cabbage Based on Growing Degree Days in Korea (생육도일(GDDs)에 따른 '춘광' 봄배추의 적정 재배 작기 예측)

  • Wi, Seung Hwan;Song, Eun Young;Oh, Soon Ja;Son, In Chang;Lee, Sang Gyu;Lee, Hee Ju;Mun, Boheum;Cho, Young Yeol
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.20 no.2
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    • pp.175-182
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    • 2018
  • Knowledge of the optimum cultivation period for Chinese cabbage would help growers especially in spring in Korea. Growth and yield of Chinese cabbage in a temperature gradient chamber was evaluated for the growing periods of 64 days from three set of transplanting dates including March 6, March 20, and April 3 in 2017. Air temperature in the chamber was elevated step-by-step, by $2^{\circ}C$ above the ambient temperature. This increment was divided into three phases; i.e. low (ambient+$2^{\circ}C$, A), medium (ambient+$4^{\circ}C$, B), and high temperature (ambient+$6^{\circ}C$, C). The fresh weight of Chinese cabbage was greater under B and C conditions in the first period and A in the second period, which indicated that GDDs affected the fresh weight considerably. However, leaf growth (number, area, length, and width) did not differ by GDDs. Bolting appeared under A condition in the first period, which was caused by low temperature in the early growth stage. Soft rot was developed under C condition in the second period and all temperature conditions in the third period, which resulted from high temperature in the late stage. Fresh weight increased when GDDs ranged from 587 to 729. However, it decreased when GDDs > 729. The maximum expected yield (16.3 MT/10a) was attained for the growing period of 64 days from transplanting date during which GDDs reached 601. The GDDs for optimum cultivation ranged from 478-724 under which the yield was about 95% (15.5 MT/10a) of maximum fresh weight. Such an optimum condition for GDDs was validated at five main cultivation regions including Jindo, Haenam, Naju, Seosan, and Pyeongtaek in Korea. In these regions, GDDs ranged from 619-719. This suggested that the optimum GDDs for Chinese cabbage cultivation would range from 478-724, which would give the useful information to expect the cultivation periods for ensuring maximum yield.