• Journal of Energy Engineering
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• v.8 no.4
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• pp.567-575
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• 1999

This study found potential ability to generate electric power using difference in water temperature between sea surface water and deep water in the East Sea which includes the East Sea Proper Water with the temperature less than 1$^{\circ}C$ throughout a year without seasonal variation. To quantify the difference in water temperature between sea surface water and deep water in the East Sea. We computed the annual mean ($^{\circ}C$), the annual amplitude ($^{\circ}C$), the annual phase (degree) and the duration time which showed more than 15$^{\circ}C$ temperature difference from the water temperature data using Harmonic analysis during 1961~1997. The best place for generating electric power in the East Sea seems to be the eastward ocean areas (36$^{\circ}$ 05'N, 129$^{\circ}$ 48'E~36$^{\circ}$ 05'N, 130$^{\circ}$ 00E'E) from Pohang city. The annual mean of the difference in water temperature between sea surface water and 500 m depth was 24$^{\circ}$C at the place to generate electric power in August according to the data of 1961~1997. the maximum duration periods with more than 15$^{\circ}C$ temperature difference were 215 days (5/5-12/10) a year in the place mentioned electricity with a stable plan. In the East Sea coastal areas of the Korean peninsula, the average minimum depth to reach the East Sea Proper Water from surface water is 300 m and fluctuates between 250 m and 350 m throughout a year. Further studies could be needed for the utilization of cold water, such as the East Sea Proper Water for energy conversion.

• The korean journal of orthodontics
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• v.29 no.1 s.72
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• pp.23-35
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• 1999

Lateral cephalograms or 251 males md 286 females were taken and pubertal growth pattern or cranial base, maxillary and mandible of 7 to 17 years old Korean children was evaluated. 10 landmarks and 16 analytical measurements were evaluated. Analytical measurement and annual difference for each age group was calculated and tested for statistical significance. Analytical measurements were classified into three groups which were cranial base, maxillary and mandibular measurements and also classified into make and female measurements. Following results were achieved. 1. The circumpuberal growth spurt was earlier in Korean females than in males. 2. Cranial base, maxilla and mandible showed circumpuberal growth. The cranial base showed a relatively smaller amount of growth than the facial complex. 3. Middle and posterior cranial base length showed a floater increase than anterior cranial base length and circumpuberal growth spurt was also more definite. 4. the forward and downward growth or maxilla results from maxillary growht itself and transposition or the maxilla due to circumsutural growth aroud the maxilla. Ar-ANS and Ar-Pr which represent maxillary position relative to the cranial base showed more growth than ANS-PNS which represents maxillary bone growth. 5. mandible showed more vertical growth than horizontal growth but without significance. 6. Alveolar gwoth of maxilla and mandible show maximum growth rate of the time of permanent teeth eruption following loss of deciduous teeth . After this period alveolar growth shows a decreasing tendency.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.20 no.2
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• pp.83-90
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• 1984

The secular fluctuations of catches and fishing grounds of mackerals and the oceanographic conditions for the fishing grounds are examined by using the data of catches of mackerals by middle and large class purse-seiner during 1951 to 1981 and those of oceanographic observation carried out by Japan Meteorological Agency. The results are as follows; The fishing grounds of mackerals are respectively distributed at northeastern and southwestern areas from the central part of the East China Sea through every season of the studied years: 1968, 1974 and 1980. The narrow belt type of fishing grounds were formed inside of the Kuroshio in spring and winter of the three years. In summer mackeral species move northward and the fishing grounds are formed in the southern sea of Korea. In winter, however, mackeral species move southward and the fishing grounds are appeared in the Tsushima Current region. The dispersion of fishing grounds is generally larger in summer and smaller in spring, and especially it is the largest in summer in 1980. It seems that the concentration and dispersion of fishing grounds are related to the depth of thermocline and the position of horizontal temperature gradient in this area.

• The korean journal of orthodontics
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• v.32 no.4 s.93
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• pp.265-274
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• 2002

Among many maturation indicators of growing patients, menarche and skeletal maturity are useful to assess growth and development, and the changes of the first and third finger are relatively important in hand-wrist X-rays. The objective of this study was to evaluate the relationship between menarche and the changes of the phalanx of the first and third finger and compare skeletal maturation among different malocclusion types. The sample used in this study was 29 Class 1,27 Class II and 27 Class III females whose hand-wrist X-rays had been taken with 6 month interval before the appearance of ulnar sesamoid ossification till the phalanges of the fingers were almost fused. The results were as follows. 1. There was no skeletal maturity difference among malocclusion types. 2. There was no difference in the mean chronologic age of menarche among different malocclusion types and that was $12.30\pm0.98$ years. 3. The ulnar sesamoid was observed at $10.35\pm1.01$ years, and on distal phalanx of the first finger, epiphyseal capping appeared at $11.26\pm1.04$ years and fusion at $13.12\pm1.06$ years. The epiphyseal capping on middle phalanx of the third finger was observed at $11.57\pm1.02$ years and fusion at $13.72\pm1.04$ years. 4. The timing of menarche occurred around the same time as the fusion process of distal phalanx of the first finger(p<0.001, r=0.82) and the initiation of fusion of middle phalanx of the third finger(p<0.001, r=0.78). Therefore, we can give the aid when we evaluate the growth and development of growing females seeing the changes at phalanx of the first and third finger.

• Journal of The Korean Society of Grassland and Forage Science
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• v.5 no.2
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• pp.100-105
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• 1985

To find out the optimum level of nitrogen fertilization and better distribution of application time for seed production of Festuca arundianacea S. (var. Alta), this filed experiment was performed at Livestock Experiment Station in Suweon, during 1979 to 1981. The treatments used in this study were three nitrogen fertilizing levels (120, 180 and 240kg/ha) and four different methods of nitrogen distribution (i. single application of whole amount in early Spring, ii. 50 percent each in Autumn and early Spring, iii. 50 percent each in early Spring and at begin of heading stage and iv. 50 percent in Autumn and 25 percent in early Spring and at begin of heading stage respectively). The experiment was arranged as a split-plot design with 4 replications and performed at the experimental field of the Livestock Experiment Station in Suweon, during 1979 to 1981. The results obtained are summarized as follows: 1. Date of heading stage of Festuca arundinacea was about May 21 and that of flowering stage was June 1 to 3. The optimum stage for the seed harvesting of Festuca arundinacea (var. Alta) was June 25 about 22 to 23 days after full flowering stage. Average plant height was about 127cm and the panicle length, 24cm. 2. 1000 grain weight was 2.72g and the number of panicles were 85 to 107 per square meter. 3. The mean seed wield for two years was 678.8kg/ha with the average of whole treatments and 781.9kg/ha with the best treatment (50 percent in Autumn and 25 percent in early Spring and at begin of heading stage with 240kg/ha respectively). 4. The average germination rate of harvesting seeds was 87.0 percent and it was increasing trend according to frequent application of fertilizer. 5. The average DM yield of aftermath seed harvesting was 6155kg/ha with two cut, and it was the largest DM yield from the higher nitrogen level and also from the single application in early Spring.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.4
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• pp.428-433
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• 1989

The objective of this experiment was to determine if there were feasible to transplant infant rice seedling for machine transplanting. Cultivars tested were Sobaegbyeo and Daecheongbyeo, ]aponica type cultivars. Infant seedling, young seedling and semi-adult seedling were raised with sailor rock wool in seedling tray from 1986 to 1988. Infant rice seedling raised more than 4 days after sowing with rock wool was uniform, and low in ratio of missing hill at machine transplanting. Tiller number per m$^2$ was more in infant rice seedling, young seedling and semi-adult seedling, in that order. Heading dates were not significantly different among seedlings applied, however rice plant sown directly was later 4 or 5 days than any other seedlings. Panicle number per m$^2$ was more in infant seedling than in semi-adult seedling, but ripened ratio was lower in infant seedling due to lodging. Thus there were not greatly different in yield among seedlings tested. Therefore infant rice seedling (more than 5cm in plumule length) raised for 7 days was most optimum, and rock wool would be used as a nursery soil instead of nursery soil for raising infant rice seedling in machine transplanting.