• 한국해양학회지
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• v.29 no.2
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• pp.145-151
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• 1994

Investigations on distributions of bacterial abundance and production in the mideast part of the Yellow Sea were made in August and October, 1991 as a part of study of "The Exploitation Research of Marine Resources on the Yellow Sea". Here, we report spatial and temporal characteristics of distributions of bacteria in the mideast part of the Yellow Sea including data reported by Son (1989) for the same area. During the whole study period, bacterial abundance ranged from 0.5${\times}$10/SUP 8/ 1/SUP -1/ to 19${\times}$10/SUP 8/ 1/SUP -1/. Seasonal changes and the difference between two studies in bacterial abundance were less than 3.5 fold ar each station in the study area, except October, 1991. An interesting result was that bacterial abundances except October, 1991 were generally lower than those expected from the established relationship between chlorophyll and bacterial abundance in the oceans. For the bacterial abundance observed in October 1991, controlling factor(s) of bacteria might be different from the rest of study period. Bacterial production (0.1∼2.9ug C 1/SUP -1/ d/SUP -1/) comprised a small fraction (18${\pm}$11%) of primary production. Though data are limited, low bacterial abundances compared to chlorophyll concentration and low values of bacterial production to primary production seemed to occur in the mideast part of the Yellow Sea. Unravelling the causes of these phenomena would be necessary to understand the ecology of bacteria in the region.

• Korean Journal of Soil Science and Fertilizer
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• v.19 no.3
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• pp.211-216
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• 1986

To establish a suitability grouping system of paddy soils for double or multiple cropping with rice which is intensively practiced in the southern parts of Korea, a few basic experiments were carried out for two years. The results are summarized as follows; 1. The potential productivities of the paddy soils which were tested without any fertilizer in the pots of subsoil samples by the double cropping of rice and other upland crops were resulted that the soils of "Moderately well drained" fine silty textured were the highest while the soils of "Poorly drained" sandy were the lowest, and the productivities could be clearly comparable according to the differences of soil conditions. 2. The decomposability of organic matter also was higher in the soils of "Moderately well drained" than the "Imperfectly drained". The coarse loamy and coarse silty textured soils were high in the upland condition and in the early stages of submerging while the fine loamy and fine silty textured soils were high at the late stage of submerging in the rates of organic matter decomposition. 3. The days to be reached to tillable condition after rainfall in fine loamy textured soils were about 5 days earlier than the clayey soils. The period of tillable condition of fine clayey soils with "Moderately well drained" was the longest and that of the fine loamy textured soils was the shortest. But the soils with "Imperfectly drained" were not clear among soil textural classes. 4. The lower the ground water table the higher was the productivity indices. The variation of ground water table in the medium textured soils was higher than the both of coarse and fine textured soils among "Moderately well drained". But it was observed the opposite in the soils of "Imperfectly drained".

• The Transactions of the Korean Institute of Power Electronics
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• v.15 no.2
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• pp.87-95
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• 2010

As the information oriented society is developing, computer is one of the necessities in our daily life. Especially, the client-server system based on internet is widely used due to the enormous amounts of data and the increasing awareness of the data security. Under these circumstances, the market of the server computer with the $57 billion global market is increasing steadily regardless of economic conditions. However, the domestic server market entirely depends on overseas companies with high technical skills and production power. Therefore, we investigates technology and development trends of the server power system to assist domestic companies in entering the global server power system market in this special paper.

• Korean Journal of Agricultural and Forest Meteorology
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• v.14 no.2
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• pp.89-97
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• 2012

This study was conducted to estimate forest site productivity and productive areas of Quercus acutissima and Quercus mongolica using environmental factors including climatic variables. Using the data set from digital forest site map and forest climatic map, a total of 42 environmental variables were regressed on site index for developing the best site index equations for Quercus acutissima and Quercus mongolica. Five to six environmental factors by species were selected as independent variables in the best site index equations. For the site index equations, three evaluation statistics (i.e., mean difference, standard deviation of difference, and standard error of difference) were applied to the test data set for the validation of the results, The site index equations fitted well to the test data set with relatively low bias and variation. As a result, it was concluded that the site index equations by species were well capable of estimating site quality. Finally, based on the site index equations, the productive areas by species were estimated by applying GIS technique to the digital forest maps. In addition, the distribution of productive areas by species was illustrated.

• Journal of The Korean Society of Grassland and Forage Science
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• v.24 no.3
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• pp.261-264
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• 2004

New orchardgrass(Dactylis glomerata L.) variety named as 'Kordi' was developed by the National Livestock Research Institute(NLRI) in 2003. Five superior clones on selected to develope the new variety of orchardgrass, and polycrossed for synthetic seed production. Synthetic seeds were examined on the agronomic growth characteristics and forage production at Suwon from 1995 to 1998, and regional trials were conducted in Suwon, Pyungchang and Jeju from 2001 to 2003 and Icsan in 2003, respectively. 'Kordi' showed semi-erect growth habit in fall and spring, and long type in length of flag leaf and short in upper internode. Plant height of 'Kordi' was little short compared to that of standard variety, Ambassador, and heading date was delayed about 3 days as 14th May compared to Ambassador. Characters such as winter hardiness. lodging tolerance, regrowth, disease resistance of 'Kordi' were stronger or better than those of Ambassador. 'Kordi' showed $10\%$ higher dry matter yield as 15,174 kg/ha compared to Ambassador. Nutritive value was appeared to be similar in both varieties.

• Journal of The Korean Society of Grassland and Forage Science
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• v.23 no.3
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• pp.203-206
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• 2003

New orchardgrass(Dactylis glomerata L.) variety named as “Jangbeol 101” was developed by the National Livestock Research Institute(NLRI) in 2002. To develope the new variety of orchardgras, 5 superior clones were selected and polycrossed for seed production. Synthetic seeds were examined on the agronomic growth characteristics and forage production at Suwon from 1995 to 1998, and regional trials were conducted in Suwon, Namwon and Pyungchang from 1999 to 2002 and Jeju from 2000 to 2002, respectively. “Jangbeol 101” showed semi-erect growth habit in fall and spring and medium type in length of flag leaf and upper internode. Plant height of “Jangbeol 101” was short compared to that of standard variety, “Ambassador” and heading date was delayed about 2 days as 14th May compared to Ambassador. Characters such as winter hardiness, regrowth, moisture tolerance, disease resistance of “Jangbeol 101” were stronger or better than those of Ambassador. “Jangbeol 101” showed 9% higher dry matter yield as 12,374 kg/ha compared to Amabassador. Nutritive value was appeared to be similar in both varieties.

• Applied Biological Chemistry
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• v.15 no.1
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• pp.41-47
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• 1972

Comparative study on dynamic change of canopy structure during ripening period were carried out by using newly bred high yield rice cultivar (IR 667-Suwon 213) and a commercial variety, Jinhung in relation to nitrogen nutrition. The results were as follows. 1. Canopy structure pattern (vertical distribution of dry matter density at heading)was vertical type for Jinhung and horizontal type for IR 667. 2. The vertical distribution pattern of leaf area density (or weight) in the canopy was central dominant type for IR 667 while apical dominant type for Jinhung. 3. Canopy conservation pattern and percent distribution pattern of leaf area density followed the vertical distribution pattern of leaf area density. 4. Canopy persistence was weaker in IR 667, thus they have smaller canopy conservation ratio indicating faster senescence. 5. Slow supply of nitrogen (sulfur coated urea) showed a trend to change the apical dominant pattern into the central dominant pattern by the conservation of central portion, and it-resulted in higher yield though nitrogen nutrition did little affect canopy pattern. 6. The central and apical dominant pattern appeared to be well matched to the upper leaf-dependent type and the lower leaf-dependent type of grain yield, respectively.

• 한국해양학회지
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• v.27 no.3
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• pp.237-246
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• 1992

In order to examine controlling factors on primary productivity and assimilation Number of phytoplankton, chlorophyll-a concentrations, light intensity, temperature, salinity and transparency were measured in the Kyonggi Bay and in the mid0eastern coast of Yellow Sea from March 1989 to October 1990. Chlorophyll-a concentration of phytoplankton ranged from 0.91 to 4.30 ug/; in the Kyonggi Bay, and from 0.78 to 4.97 ug/l in the mideastern coast of Yellow Sea. Daily averaged primary productivities and annual primary productivities of phytoplankton ranged from 37.23 to 1104.44 (averaged 361.54) mgC/m$^2$/day, 131.96hC/m$^2$/yr in the mid0eastern coast of Yellow Sea, respectively. Assimilation Number of phytoplankton ranged from 1.47 to 28.28 mgC/mg chl-a/hr in the Kyonggi Bay, and of phytoplankton in the Kyonggi Bay was higher than that of the mid0eastern coast of Yellow Sea. Light utilization efficiencies (a) in the P-I curve ranged from 0.03 to 0.93 [mgC/mg chl-a/hr]/[ue/m$^2$/sec]in the Kyonggi Bay, and from 0.01 to 0.62 [mgC/mg chl-a/hr]/[ue/m$^2$/sec] in the mid-eastern coast of Yellow Sea. Their results indicated that phytoplankton in the Kyonggi Bay utilized light more efficiently than those of the mid0eastern coast of Yellow Sea. The average values of I/SUB k/ were 48.15 ue/m$^2$/sec in the Kyonggi Bay, and 120.37 uE/m$^2$/sec in the mid-eastern coast of yellow Sea. It means the phytoplankton populations in the Kyonggi Bay seem to be adapted to lower light intensity than those of the mid-eastern coast of Yellow sea.

• Journal of The Korean Society of Grassland and Forage Science
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• v.23 no.3
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• pp.207-210
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• 2003

"Jangbeol 102" is a new orchardgrass(Dacrylis glomerata L.) variety developed by the National Livestock Research Institute(NLRI) in 2002. To develope the new variety of orchardgrass, 5 superior clones were selected and polycrossed for seed production. Agronomic growth characteristics and forage production of "Jangbeol 102" were examined at Suwon from 1995 to 1998, and regional trials were conducted in Suwon, Namwon and Pyungchang from 1999 to 2002 and Jeju from 2000 to 2002, respectively. "Jangbeol 102" showed semi-erect growth habit in fall and spring and medium to long type in length of flag leaf and upper internode. Plant height of "Jangbeol 102" was similar to that of standard variety, "Ambassador" and heading date was I day faster as 11th May compared to Ambassador. Characters such as winter hardiness, regrowth, moisture tolerance, disease resistance of "Jangbeol 102" were stronger or better than those of Ambassador, specially in regrowth and disease resistance. "Jangbeol 102" showed 18% higher dry matter yield(13,430kg/ha) compared to Amabassador. Nutritive value was appeared to be similar in both varieties.assador. Nutritive value was appeared to be similar in both varieties.

• Korean Journal of Soil Science and Fertilizer
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• v.26 no.4
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• pp.230-235
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• 1993

This study was carried out to investigate the supplying capacity of various forms(Water soluble, exchangeable, and available) of potassium in soils of different site quality by using surface soils from the Japanese cedar(Cryptomeria japonica) forests in Cheju island. Major results can be summerized as follows. Using continuous leaching methods with 0.01N-HCl, accumulated amounts of available potassium from surface soils of site upper and site low were about 0.6me/100g and 0.4me/100g, respectively. The release ratio of available potassium in the first $1{\ell}$ leaching of 0.01N-HCl to the total available potassium leached with $6{\ell}$ of 0.01N-HCl was over 80% for both sites, and this suggester that surface soil of both sites had the weak potassium adsorptivity as the typical volcanic ash soil. The ratio of the exchangeable potassium to the water soluble potassium was 1 : 1 for both sites. The ratio of the exchangeable potassium to the available potassium was 1 : 1 for the site low but the smaller ratio value for the site upper, indicating that the potassium supplying power of the site upper was greater than that of the site low. Available potassium was highly correlated with exchangeable Ca($0.83^{**}$) and Mg($0.84^{**}$).