• Journal of Korean Society of Rural Planning
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• v.16 no.4
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• pp.109-116
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• 2010

Climate change is known to affect both natural and managed ecosystems, and will likely impact on the terrestrail carbon balance. This paper reports the effects of climate change on spatial-temporal changes in carbon reductions in South Korea's during 2000-2100. Future carbon (C) stock distributions are simulated for the same period using various spatial data sets including land cover, net primary production(NPP) and leaf area index (LAI) obtained from MODIS(Moderate Resolution Imaging Spectroradiometer), and climate data from Data Assimilation Office(DAO) and Korea Meteorological Administration(KMA). This study attempts to predict future NPP using multiple linear regression and to model dependence of soil respiration on soil temperature. Plants store large amounts of carbon during the growing periods. During 2030-2100, Carbon accumulation in vegetation was increased to $566{\sim}610gC/m^2$/year owing to climate change. On the other hand, soil respiration is a key ecosystem process that releases carbon from the soil in the form of carbon dioxide. The estimated soil respiration spatially ranged from $49gC/m^2$/year to $231gC/m^2$/year in the year of 2010, and correlating well with the reference value. This results include Spatial-Temporal C reduction variation caused by climate change. Therefore this results is more comprehensive than previous results. The uncertainty in this study is still large, but it can be reduced if a detailed map becomes available.

• Journal of Sericultural and Entomological Science
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• v.29 no.1
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• pp.12-19
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• 1987

This study was carried out to investigate the effects of climatic conditions on the budding of buds and the growth of shoots of mulberry (Morus alba L.) at Suwon for the period of six years from 1978 to 1983. The results are summarized as follows. 1. The period that influenced most greatly on mulberry budding and foliating of it's buds was from late part of March to middle part of April in the district of Suwon, Korea. 2. Temperatures in soil 20cm deep during the period from late part of March to middle part of April had high correlations with budding dates. 3. It was disclosed that the budding date had high correlations with the date of bud shaped swallow-bill (r=0.9861**), date of the third leaf(r=0.97**), and date of the fifth leaf(r=0.96**), respectively. 4. The higher the average temperature of April became, the longer the length of shoots became. 5. The earlier the budding date and foliating date came, the larger the leaf yield became. However, with excessive amount of precipitation after early budding and foliating, the leaf yield was not increased in proportional. 6. The longer the growing period of the shoots became, the larger the leaf yield became.

• Korean Journal of Medicinal Crop Science
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• v.26 no.5
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• pp.362-369
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• 2018

Background: For stable induction of tetraploidy in Fallopia multiflora Haraldson, colchicine was treated to establish the condition of induction and investigated the morphological and cytogenetic traits of the tetraploid plants obtained compared to those of diploid ones. Methods and Results: For the induction of tetraploidy, F. multiflora plants were soaked in aqueous solutions of colchicine at various concentration (0.1, 0.5, and 1.0%). After this, 2% dimethyl sulfoxide (DMSO) was added at room temperature on a shaker set at 150 rpm for periods of 12, 24, and 48 h. The induction rate of tetraploids appeared to be the highest in plants treated with 0.5% colchicine for 24 h. As the colchicine concentration and soaking time increased above these levels, the growing tip of the roots did not develop and they began to rot. When compared to diploid plants, tetraploids differed greatly in various characteristics, including the sizes and shapes of the leaves, fruits, flowers and roots. The induced tetraploid F. multiflora had larger guard cells, and chloroplasts, increased number of chloroplast in the guard cells and decreased stomatal densities. Conclusions: When colchicine induced plants for tetraploid, it can be distinguished from diploids, in various characteristics such as morphological changes as stomatal size, number of chloroplasts per guard cell, number of chromosomes and flow cytometry. Therefore, it proved that these methods are suitable, quick and easy methods for the identification of the ploidy level of F. multiflora.

• Journal of The Korean Society of Agricultural Engineers
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• v.56 no.6
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• pp.149-158
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• 2014

The effects of spot cooling on growing ever-bearing strawberry in hydroponic cultivation during summer by spot cooling system was estimated in plastic greenhouse located in Pyeongchang. The temperature of cooling water was controlled by heat pump and maintained at the range of $15{\sim}20^{\circ}C$. Cooling pipes were installed in root zone and very close to crown. Spot cooling effect was estimated by applying system in three cases which were cooling root zone, crown plus root zone, and crown only. White low density polyethylene pipe in nominal diameter of 16 mm was installed on crown spot, and Stainless steel flexible pipe in nominal diameter of 15A was installed in root zone. Crown and root zone cooling water circulation was continuously performed at flowrates of 300 ~ 600 L/hr all day long. Strawberry yields by test beds were surveyed from Aug. 1 to Sep. 30. The accumulated yield growth rate compared with a control bed of crown cooling bed was 25 % and that of crown plus root zone cooling bed was 25 % and that of root zone cooling bed was 20 %. The temperatures of root spot in root zone cooling was maintained at $18{\sim}23.0^{\circ}C$ and that of crown spot in crown cooling was maintained at $19{\sim}24^{\circ}C$. Also, the temperatures of root spot in crown plus root zone cooling bed was maintained at $17.0{\sim}22.0^{\circ}C$ and that of crown spot was maintained at $19{\sim}25^{\circ}C$.

• Journal of Powder Materials
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• v.21 no.3
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• pp.215-221
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• 2014

Translucent alumina is a potential candidate for high temperature application as a replacement of the glass or polymer. Recently, due to the increasing demand of high power light emitting diode (LED), there is a growing interest in the translucent alumina. Since the translucent property is very sensitive to the internal defect, such as voids inside or abnormal grain growth of sintered alumina, it is important to fabricate the defect-free product through the fabrication process. Powder injection molding (PIM) has been commonly applied for the fabrication of complex shaped products. Among the many parameters of PIM, the flowability of powder/binder mixture becomes more significant especially for the shape of the cavity with thin thickness. Two different positions of the gate were applied during PIM using the disc type of die. The binder was removed by solvent extraction method and the brown compact was sintered at $1750^{\circ}C$ for 3 hours in a vacuum. The flowability was also simulated using moldflow (MPI 6.0) with two different types of gate. The effect of the flowability of powder/binder mixture on the microstructure of the sintered specimen was studied with the analysis of the simulation result.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.1
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• pp.32-38
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• 2005

A long-term study initiated in 1989 at San-born Field, Columbia, Missouri, was designed to evaluate the affect of environmental factors, nitrogen application, and crop rotation on soybean (Glycine max [L.] Merr.) seed composition. Soybeans were grown as part of a four- year rotation which included corn (Zea maize L.), wheat (Triticum aestivum L.), and red clover (Trifolium pratense L.). Results from soil tests made prior to initiation of the study and subsequently every five years, were used to calculate application rates of nitrogen, phosphorus, and potassium necessary for target yield of pursuant crops. In the experimental design, nitrogen was applied to one-half of the plot on which the non-leguminous crop, either corn or wheat was grown. Analysis of soybean seed by near infrared reflectance spectroscopy collected over an 11-year period revealed a linear increase in protein and decrease in oil content. Application of nitrogen fertilizer to non-leguminous crops did not have an apparent effect on total protein or oil content of subsequent soybean crop. Analysis of soybean seed proteins by sodium dodecyl sulfate polyacrylamide gel electrophoresis in conjunction with computer­assisted densitometry revealed subtle changes in the accumulation of seed proteins. Immunoblot analysis using antibodies raised against the $\beta-subunit$ of $\beta-conglycinin$ showed a gradual increase in the accumulation of the 7S components during successive years of the experiment. A linear increase in temperature and decrease in rainfall was observed from the onset of data· collection. Higher temperatures during the growing season have been linked to increased protein and diminished oil content of soybean, thus changes observed in this study are possibly related to climatic conditions. However, crop rotation and subsequent changes in soil ecology may contribute to these observed changes in the seed composition.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.2
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• pp.227-234
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• 2015

To obtain geographical range and growth-kinetics parameters of mottled sake (Beringraja pulchra) populations in the Yellow Sea, three mark-recapture experiments were carried out. Overall, 991 tagged individuals were released, and 4.1% of them were recaptured with the mean release period of 339 d (range, 8-1,420 d) and the mean growth rate of $1.4cm\;mon^{-1}$ (female, $1.5cm\;mon^{-1}$; male $1.3cm\;mon^{-1}$). In the first experiment, 667 individuals were released at Heuksan Island from April to June, 2007-2009, and 30 individuals were recaptured mainly at the north and the north-east coasts of the island, indicating absence of migration to the south of the island. In the second experiment, 323 individuals were released at several fishing grounds scattered in the Yellow Sea in 2010-2013, and 11 individuals were recaptured at points deviated to all directions from the releasing points. As the last, one individual was released with pop-up satellite archival tag at a costal point ($34^{\circ}37.2$'N, $124^{\circ}59.3$'E) off Hong Island on May 21, 2010. The tagged individual migrated to a north-east location ($35^{\circ}50.4$'N, $126^{\circ}03.6$'E) of Eocheong Island by Aug. 25, 2010. The data archived for the three months in the tag indicated that the migration path had depths of 48-80 m and temperature of $12.6-14.4^{\circ}C$. The results indicated that mottled sake populations had a localized habitat ranges at the north of Heuksan Island and the west of Hong Island while growing at the rate of $1.4cm\;mon^{-1}$.

• Journal of Animal Environmental Science
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• v.17 no.1
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• pp.33-38
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• 2011

Economic development involves increase in life expectancy as well as human health care. Consequently, demand for fish meal and fish oil is rapidly growing. In particular, Krill (Eupausia superba) oil product is in high demand due to its rich unsaturated-fatty acid, and thus stable supplies are necessary in the krill oil market. It is required for captured krills to be immediately frozen and stored during ship transport, since proteins of the krill are quickly denatured in natural temperature condition. However, the transportation cost has been sharply increased, which encourages researchers to involve in studies for development of efficient oil extraction process. In this study, a solid/liquid separation technique on boat for the krill oil was developed through triple separation tests using only a separator or using either brush or crusher prior to the separator. The separation tests revealed that the efficiency were 46.2, 60.2 and 60.4 % by the separator, combination with brush, and combination with crusher, respectively. In addition, it was found that byproduct, extracted cake, derived from the separation process could be used as a feed stuff. These results suggest that smashing using the brush or crusher prior to the separator is more efficient than using only the separator.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2018.06a
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• pp.101-101
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• 2018

Quantitative measurement of chloride ion concentration has an important role in various fields of electrochemistry, medical science, biology, metallurgy, architecture, etc. Among them, its importance of architecture is ever-growing due to unexpected degradations of building structure. These situations are caused by corrosion of reinforced concrete (RC) structure of buildings. And chloride ions are the most powerful factors of RC structure corrosion. Therefore, precise inspection of chloride ion concentration must be required to increase the accuracy of durability monitoring. Multi-walled Carbon nanotubes (MWCNTs) have high chemical resistivity, large surface area and superior electrical property. Thus, it is suitable for the channels of electrical signals made by the sensor. Silver nanoparticles were added to giving the sensing property. CuBTC, one of the metal organic frameworks (MOFs), was employed as a material to improve the sensing property because of its hydrophilicity and high surface area to volume ratio. In this study, sensing element was synthesized by various chemical reaction procedures. At first, MWCNTs were functionalized with a mixture of sulfuric acid and nitric acid because of enhancement of solubility in solution and surface activation. And functionalized MWCNTs, silver nanoparticles, and CuBTC were synthesized on PTFE membrane, one by one. Electroless deposition process was performed to deposit the silver nanoparticles. CuBTC was produced by room temperature synthesis. Surface morphology and composition analysis were characterized by scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS), respectively. X-ray photoelectron spectroscopy (XPS) was also performed to confirm the existence of sensing materials. The electrical properties of sensor were measured by semiconductor analyzer. The chloride ion sensing characteristics were confirmed with the variation of the resistance at 1 V.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.1
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• pp.8-14
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• 2008

Ammonia ($NH_3$) volatilization from a silty clay loam paddy soil applied with non, straight urea, and coated urea, respectively, under transplanting in Milyang, Korea from 2002 and 2003 was simulated by a Water and Nitrogen Management Model (WNMM). Based on the data from the in-situ measurements, $NH_3$ volatilization during the rice growth was 6.04% and 1.46% of the applied nitrogen (N) from straight urea and coated urea, respectively. The bulk aerodynamic approach in WNMM satisfactorily predicted the difference in $NH_3$ loss during the given rice growing seasons from the two urea fertilizers. $R^2$ for the correlation between the predicted and observed NH3 loss during the calibration year (2002) was 0.53 less than 0.68 of the application year (2003). This difference could be due to the weather condition such as heavy rainfall and temperature during the calibration year.