• The korean journal of orthodontics
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• v.22 no.2 s.37
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• pp.413-426
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• 1992

In order to analyze the relationship between teeth and basal bone for the maintainance of the good occlusion, the mesiodistal width of teeth, the basal arch width and the basal arch length were measured on the study model of the normal occlusion group and Angle's class I malocclusion group (non-extraction group, extraction group) The Maximum tooth material, the percentage of basal arch width to maximum tooth material, the percentage of basal arch length to maximum tooth material and the percentage of basal arch width plus basal arch length to maximum tooth material were caculated, and then statistical analysis was done. From thie study, the obtained results were as follows; 1. In maxilla, the percentage of basal arch width to maximum tooth material was $46.9{\pm}2.6\%$ in normal occlusion group, $49.4{\pm}3.9\%$ in non-extraction group, and $42.5{\pm}3.3\%$ in extraction group. In mandible, that was $46.6{\pm}2.4\%$ in normal occlusion group, $47.5{\pm}4.0\%$ in non-extraction group, and $42.6{\pm}2.6\%$ in extraction group. 2. In maxilla, the percentage of basal arch length to maximum tooth material was $33.4{\pm}1.9\%$ in normal occlusion group, $33.9{\pm}1.8\%$ in non-extraction group, and $28.7{\pm}2.5\%$ in extraction group. In mandible, that was $34.4{\pm}4.3\%$ in normal occlusion group, $36.5{\pm}1.9\%$ in non-extraction group, and $31.5{\pm}2.5\%$ in extraction group. 3. In maxilla, the percentage of basal arch width plus basal arch length to maximum tooth material was $80.3{\pm}3.4\%$ in normal occlusion group, $83.3{\pm}4.8\%$ in non-extraction group, and $71.2{\pm}4.3\%$ in extraction group. In mandible, that was $81.0{\pm}5.2\%$ in normal occlusion group, $84.0{\pm}5.4\%$ in non-extraction group, and $74.1{\pm}4.1\%$ in extraction group. 4. In Maxilla, the $95\%$ confidence interval of the percentage of basal arch width to maximum tooth material was $46.3-47.5\%$ in normal occlusion group, $48.1-50.7\%$ in non-extraction group, and $41.7-47.2\%$ in extraction group. In mandible, that was $46.1-47.2\%$ in normal occlusion group, $46.1-48.8\%$ in non-extraction group, and $42.0-43.3\%$ in extraction group. 5. In maxilla, the $95\%$ confidence interval of the percentage of basal arch length to maximum tooth material was $32.9-33.9\%$ in normal occlusion group, $33.3-34.5\%$ in non-extraction group, and $28.1-29.2\%$ in extraction group. In mandible, that was $33.4-3.4\%$ in noraml occlusion group, $35.8-37.2\%$ in non-extraction group, and $30.9-33.1\%$ in extraction group. 6. In maxilla, the $95\%$ confidence interval of thepercentage of basel arch width plus basal arch length to maximum tooth material was $79.5-81.0\%$ in normal occlusion group, $81.6-84.9\%$ in non-extraction group, and $70.1-72.2\%$ in extraction group. In mandible, that was $79.8-82.2\%$ in normal occlusion group, $82.1-85.5\%$ in non-extraction group, and $73.1-75.1\%$ in extraction group. 7. There was correlation between maxilla and mandible in the maximum tooth material, the basal arch width, the basal arch length, the percentage of basal arch width to maximum tooth material, the percentage of basal arch length to maximum tooth material and the percentage of basal arch width plus basal arch length to maximum tooth material, but not in the basal arch length of male of the extraction group. * A thesis submitted to the Council of the Graduate School of Kyungpook national University in partial fulfillment of the requirements for the degree of Master of Dental Science in December, 1991.

• Korean Journal of Soil Science and Fertilizer
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• v.28 no.4
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• pp.306-311
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• 1995

A nutrient solution culture experiment was conducted in the greenhouse of Suwon Campus, Kyung-Hee University from May 22 to July 10, 1995, to determine the effects of sulful application on seedling growth of Kwanganok and Hwengsungok cultivars of corn. Plants were harvested at weekly interval for seven weeks, at which time plant height, leaf area and dry matter yield of corn seedling were measured. Sulfer was treated with $MgSO_4{\cdot}7H_2O$ so that sulfur concentrations of cultural solution are 0, 68, 136 and 204ppm for treatments of without sulfer(-S), control(C), twofold concentration(2S) of control and threefold contration(3S) of control, respectively. The plant height, leaf area and dry matter yield during the seven weeks of Kwanganok cultivar was decreased in order of C>2S>3S>-S, 2S>C>3S>-S and 2S>3S>C>-S application pot, respectively. In Hwengsungok cultivar, those were decreased in order of C>-S>3S>2S, C>3S>2S>-S and C>3S>-S>2S application pot, respectively. The total plant height, leaf area and dry matter yield during the whole period of Kwanganok and Hwengsungok cultivars were decreased in the seedling grown under without sulfur treatment compared with the other sulfur treatments. In Hwengsungok cultivar, plant height, leaf area and dry matter yield of seedlings were increased more in control sulfur treatment pot than the other sulfur treatment pot during the whole period. The crop growth rates of seedling of both cultivars in all treatments were slowly increased until the 3th week after planting and its were showed up and down CGR's thereafter, but Hwengsungok cultivar with C treatment pot maintained a steady increase in CGR until the end of the experiment period.

• The Korean Journal of Pesticide Science
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• v.6 no.2
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• pp.96-104
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• 2002

This study was carried out to investigate cytotoxicity of paraquat on NIH 3T3 fibroblasts, toxicity of paraquat and compensatory effects of 3-methylcholanthrene (3-MC) on the rat lung. In order to conduct MIT [3-(4,5-Dimethylthiazol-2-yl) -2,5-diphenyl -2H-tetrazolium-bromide] and NR (Neutral red) assay, the $5.0{\times}10^4cell/ml$ of NIH 3T3 fibroblast in each well of 24 multi-dish were cultured. After 24 hours, the cells were treated with solution of paraquat (1, 25, 50 and $100{\mu}M$ respectively). After the NIH 3T3 fibroblast of all groups were cultured in same condition for 48 hours. MIT and NR assay were performed to evaluate the cytotoxicity of cell organelles. $MTT_{50}\;and\;NR_{50}$ of paraquat were $1668.97{\mu}M\;and\;1030.85{\mu}M$, respectively. These $IC_{50}$ of Paraquat were decided as a low cytotoxicity by Borenfreund and Puemer (1984). In order to observe the toxicity and compensatory effects of paraquat on the rat lung, Spraque Dawley male rats were used as experimental animals and were divided into paraquat only treated group and simultaneous application group of paraquat and 3-MC, at 30 min and 1, 3, 6, 12, 24, 48 and 96 hrs interval after each treatment. The animals were sacrificed by decapitation and their or the lungs were immediately removed, immersed in fixatives, and were processed with routine method for light microscopic study. Paraffin sections were stained with H&E and iron hematoxylin of Verhoeff. Under the light microscopy, erythrocytes were full in alveolar capillaries at 3 hrs and congested at 24 hrs after paraquat administration. The great alveolar cells (Type II cell) were increased and mitosis of great alveolar were observed in interalveolar septa. Many lymphocytes, macrophages and polymorphonuclear (PMN) cells were observed in connective tissue surrounding lung tissue and germinal center in lymph follicles of terminal bronchiole. Alveolar macrophages were increased in interalveolar septa and alveoli at 48 hrs. And observed many alveolar macrophages at 96 hrs. In iron hematoxylin stain of Verhoeff, Collagen fiber were increased in respiratory bronchiole, interalveolar septa and alveoli and breath of alveoli, and alveolar pore were broaden. But, in paraquat plus 3-MC treated group, morphological changes were mild in lung tissue. These results indicate that 3-MC has a compensatory effects against toxicity of paraquat by conjugation with oxygen.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.1
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• pp.26-33
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• 1996

A nutrient solution culture experiment was conducted in the greenhouse at Suwon Campus. Kyung-Hee University from May 23 to July 11. 1995, to determine the effects of potassium application on seedling growth of Kwanganok and Hwengsungok cultivars of corn. Potassium was treated with four different levels, which are 0.248.496 and 744ppm for treatments without potassium (-k), standard potassium concentration (K), double(2k) and triple (3k) of standard potassium concentration, respectively. Plants were harvested at weekly interval for seven weeks. at which time plant height, leaf area and dry matter yield of corn seedling were measured, only chlorophyll content was taken for five weeks from three week after planting. Seedlings growth of Kwanganok and Hwengsungok cultivars was greatly retarded from planting to harvesting time in 3k treatment. The plant height, leaf area and dry matter yield of both cultivars during the whole period were decreased in order of K>2F>-K>3K, but dry matter yield of Kwanganok cultivar was decreased in order of 2K>K>-K>3K. Chlorophyll content of Kwanganok and Hwengsungok cultivars was irregularly fluctuated during growing period. but generally highest in K treatment and lowest in 3k treatment. The crop growth rates of seedlings of both cultivars were slow until the 3rd week after planting. but very fast thereafter. In general, CGR of both cultivars was higher in K and 2k treatments than -k and 3k treatments.

• Journal of Bio-Environment Control
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• v.22 no.2
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• pp.138-145
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• 2013

In order to develop the efficient control algorithm of the two-fluid fogging system, cooling experiments for the many different types of fogging cycles were conducted in tomato greenhouses. It showed that the cooling effect was 1.2 to $4.0^{\circ}C$ and the cooling efficiency was 8.2 to 32.9% on average. The cooling efficiency with fogging interval was highest in the case of the fogging cycle of 90 seconds. The cooling efficiency showed a tendency to increase as the fogging time increased and the stopping time decreased. As the spray rate of fog in the two-fluid fogging system increased, there was a tendency for the cooling efficiency to improve. However, as the inside air approaches its saturation level, even though the spray rate of fog increases, it does not lead to further evaporation. Thus, it can be inferred that increasing the spray rate of fog before the inside air reaches the saturation level could make higher the cooling efficiency. As cooling efficiency increases, the saturation deficit of inside air decreased and the difference between absolute humidity of inside and outside air increased. The more fog evaporated, the difference between absolute humidity of inside and outside air tended to increase and as the result, the discharge of vapor due to ventilation occurs more easily, which again lead to an increase in the evaporation rate and ultimately increase in the cooling efficiency. Regression analysis result on the saturation deficit of inside air showed that the fogging time needed to change of saturation deficit of $10g{\cdot}kg^{-1}$ was 120 seconds and stopping time was 60 seconds. But in order to decrease the amplitude of temperature and to increase the cooling efficiency, the fluctuation range of saturation deficit was set to $5g{\cdot}kg^{-1}$ and we decided that the fogging-stopping time of 60-30 seconds was more appropriate. Control types of two-fluid fogging systems were classified as computer control or simple control, and their control algorithms were derived. We recommend that if the two-fluid fogging system is controlled by manipulating only the set point of temperature, humidity, and on-off time, it would be best to set up the on-off time at 60-30 seconds in time control, the lower limit of air temperature at 30 to $32^{\circ}C$ and the upper limit of relative humidity at 85 to 90%.

• Magazine of the Korean Society of Agricultural Engineers
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• v.19 no.1
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• pp.4323-4337
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• 1977

The study was to estimate the effect of the rise of water temperature in the warm water pool and to make contribution to the establishment of reducing to a damage of cool water as well as to the planning for warm water pool. This observation was performed in Wudu warm water pool located at Wudu-Dong of Chuncheon for two years from 1975 to 1976. The results were showed as follows; 1. The daily variation of water temperature was the least for inset (No.1; 0.6$^{\circ}C$) the second for middle overflow (No2: 3$^{\circ}C$, No.3; 2.3$^{\circ}C$) and another for outflet (No.4; 3.6$^{\circ}C$, No.5; 3.8$^{\circ}C$) And the highest reaching time of water temperature in each block was later about 1 hour than the time at which air temperature happend in the daytime. So, the variation of water temperature was sensitive to the variation of air temperature 2. The monthly variation of water temperature at each measuring point was plotted to be increased with increase in air temperature till August (Mean monthly rising degree; No.1; 1.15$^{\circ}C$, No.2; 1.7$^{\circ}C$, No.3; 1.73$^{\circ}C$, No.4; 2.08$^{\circ}C$, No.5; 2.0$^{\circ}C$), and expressed gradually descended influence upon water temperature after August. 3. The mean temperature of inflow folwed in warm Water pool was 7.5∼12.5$^{\circ}C$, and outflow temperature was described as 13.4∼22.5$^{\circ}C$ to be climbed. And So, the rising interval of water temperature was shown as 6.7∼10.4$^{\circ}C$. 4. The correlation between the rising of water temperature and the weather condition was found out highly significant. As the result, their correlation coefficents of water temperature depending on mean air temperature, ground temperature, wind velocity and relative humidity were to be 0.93, 0.90, - 0.83 and 0.71 respectively. But there was no confrimation of the correlation on the clouds, sunlight time, volume of evaporation, and heat capacity of horizontal place. 5. The water temperature of balance during the period of rice growing in Chuncheon district was shown as table 10, and the mean of whole period was calculated as about 23.7$^{\circ}C$. 6. The observed value of the outflow temperature passed through the warm water pool was higher than that of computed, the mean difference between two value was marked as 1.15$^{\circ}C$ for blockl, 1.18$^{\circ}C$ for block2, and 0.47$^{\circ}C$ for block3, respectivly. Therefore, the ratio on the rising degree between the observed and computed were shown as 53%, 44%, and 18%, mean 38% through each block warm water pool (referring item $\circled9$ of table 11,12, and 13). Accordingly, formula (4) in order to fit for each block warm water pool was transfromed as follow; {{{{ { theta }_{w } - { theta }_{ 0} =[1-exp LEFT { { 1-(1+2 varphi )} over {cp } CDOT { A} over { q} RIGHT } ] TIMES ( { theta }_{w } - { theta }_{ 0}) TIMES C }}}} Here, correction coefficinent was computed 1.38, and being substituted 1.38 for C in preceding formula, the expected water temperature will be calculated to be able to irrigate the rice paddy. As the result, we can apply the coefficient in order to plan and to construct a new warm water pool.

• Korean Journal of Environmental Agriculture
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• v.20 no.3
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• pp.155-161
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• 2001

This study was carried out to investigate cytotoxicity of paraquat or bentazone on NIH 3T3 fibroblasts, toxicity of paraquat or bentazone, and compensatory effects of 3-Methylcholanthrene(3-MC) on the rat liver. In order to MTT assay, the $5.0{\times}10^4$ cell/mL of NIH 3T3 fibroblast in each well of 24 multidish were cultured. After 24 hours, the cells were treated with solution of paraquat or bentazone(1, 25, 50, 100 ${\mu}M$ respectively). After the NIH 3T3 fibroblast of all groups were cultured in same condition for 48 hours. MTT assay were performed to evaluate the cytotoxicity of cell organelles. Paraquat or bentazone $MTT_{50}$ were 1668.97 ${\mu}M$ and 1506.97 ${\mu}M$, respectively. These $IC_{50}$ of paraquat or bentazone were decided low cytotoxicity by Borenfreund. In order to observe the toxicity and compensatory effects of paraquat or bentazone on the rat liver, Sprague-Dawley male rats were used as experimental animals and divided into paraquat or bentazone only treated group and simultaneous application group of paraquat or bentazone and 3-MC. At 30 min and 1, 3, 6, 12, 24, 48 and 96 hrs interval after each treatment, the animals were sacrificed by decapitation and liver were immediately removed, immersed in fixatives, and processed with routine method for light microscopic study. Paraffin sections were stained with H-E, PAM and Best Carmine. Under the light microscope, degenerative changes of hepatic lobules were frequently observed in portal area from 3 hrs after paraquat or bentazone treatment. All hepatic cells were induced degenerative change at 12 hrs and more severe degenerative change at 48 hrs after paraquat or bentazone treatment. Especially, hepatic cells of bentazone only treated group were distinctly showed pyknotic. Glycogen granules were increased in portal area at 3 hrs, all hepatic cells at 12 hrs and remarkably increased at 48 hrs after paraquat or bentazone treated group. But hepatic cells of bentazone only treated group were regeneration at 48 hrs from portal area and glycogen granules of hepatic cells of paraquat or bentazone and 3-MC combination treated group showed in central area only at 48 hrs. The results indicate that 3-MC may be decrease paraquat or bentazone cytotoxicity on the rat liver.

• Journal of Wetlands Research
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• v.9 no.3
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• pp.1-12
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• 2007

In this study, the correlation of organic content with particle size and type of sediment was found out.Particle size, stratigraphic section and organic content of sediments sampled from Dalpo wetland was analyzed. Dalpo wetland consists of three wetlands, and the area of Dalpo wetland is about $31,295m^2$. The particle size analyses for sampled sediments of 7 points (3 points in wetland A, 3 points in wetland B and 1 point in wetland C) were tested. As results of the particle size analyses, the sediment particle size becomes larger as to the edge of the wetland. It is revealed in order of wetland A > wetland C > wetland B. Borehole surveys with horizontal distance in the major and minor axes of wetland A, the major and minor axes of wetland B and the major axis of wetland C were accomplished. Clayey peat deposit is distributed at 10~90 cm depth below ground surface in the major axis of wetland A. The clayey peat deposit was the most thick at the center of wetland A that horizontal distance is 100 m. As the depth below ground surface of clayey peat deposit is less than 27 cm in the wetland B, we can infer that the life for the wetland B is being finished. Sediment composition of wetland C is simple because wetland C is small scale, and clayey peat deposit is distributed at 10~34 cm depth below ground surface. Sediment sampled by borehole survey in the Dalpo wetland was cut at interval of 10 cm, then organic content was analyzed. Organic content of wetland A sediment showed more than 40% until 70 cm depth below ground surface, also sediment of wetland B is similar to wetland A until 10 cm depth below ground surface, but is showed within 20 % above 30 cm depth below ground surface. Organic content of wetland B is showed the lowest as organic content near the ground surface is about 40%. All of the three wetlands, organic content is showed higher at clayey peat deposit near to ground surface. This is caused by finer particles of the clayey peat deposit, also organic materials were supplied from dead vegetation. Organic content of the Dalpo wetland showed in order of wetland A > wetland C > wetland B. This result is caused by thickness of clayey peat deposit in sediment. Through this study, it was verified that organic content of the Dalpo wetland sediment was dominated by particle size of sediment and vegetation of the upper part.

• Korean Journal of Environment and Ecology
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• v.25 no.5
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• pp.649-657
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• 2011

This study had targeted the Manjong Junction~Hongchun interchange section of Jungang highway in order to analyze the efficiency and improvement of the highway wild-life fences. Being analyzed wild-life fence as an effective facility for the prevention of road-kill, it had founded that the wild animals did not jump over even the two layer guardrail, concrete barrier and noise barrier, fence for rock fall. For the section with high road-kill decrease effect after installing the wild-life fence, the effect was higher at wild-life fence with the height of 1.0m where the door had not been installed and the well connected points of road facility than the area with fence height of 1.5m. The road-kill decrease effect was also high at the well managed areas even if the door has not been installed. Also, road-kill had occurred by concentrating around the end of wild-life fence after installing the fence, Moreover road-kill had also occurred around the cutting section. The door of wild-life fence had higher amount of road-kill occurrence as the installation interval was closer. it was analyzed that the door management has a lot of effect on road-kill decrease. The fence for rock fall, two layer guardrail and concrete barrier having the effect of wild-life fence installed on the road would have to be installed by connecting with wild-life fences through proper facility improvement. Although the door should not be installed if possible, it should be installed as automatic door or gravity door to prevent the door from leaving the door open. An escape route has to be formed for the prompt escape away from the road for the animals entered through the ending section of the fence. The eco-corridor has to be made by restoring the soil layer of dual purpose eco-corridor forming a planting area. Also, the dead body after the accident has to be disposed to the outer section of the road immediately in order to prevent the secondary road-kill by the predator from the road-kill. The fence has to be installed as 500m or longer in both ways, in other words 1,000m or longer, from the targeted spot of minimum accident prevention while connecting up to the bridge or box culvert, etc that are next road facilities if possible to guide wild animals safely to the eco-corridor.

• Journal of Korea Port Economic Association
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• v.37 no.2
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• pp.73-89
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• 2021

The handysize bulk carriers are capable of transporting a variety of cargo that cannot be transported by mid-large size ship, and the spot chartering market is active, and it is a market that is independent of mid-large size market, and is more risky due to market conditions and charterage variability. In this study, Granger causality test, the Impulse Response Function(IRF) and Forecast Error Variance Decomposition(FEVD) were performed using monthly time series data. As a result of Granger causality test, coal price for coke making, Japan steel plate commodity price, hot rolled steel sheet price, fleet volume and bunker price have causality to Baltic Handysize Index(BHSI) and charterage. After confirming the appropriate lag and stability of the Vector Autoregressive model(VAR), IRF and FEVD were analyzed. As a result of IRF, the three variables of coal price for coke making, hot rolled steel sheet price and bunker price were found to have significant at both upper and lower limit of the confidence interval. Among them, the impulse of hot rolled steel sheet price was found to have the most significant effect. As a result of FEVD, the explanatory power that affects BHSI and charterage is the same in the order of hot rolled steel sheet price, coal price for coke making, bunker price, Japan steel plate price, and fleet volume. It was found that it gradually increased, affecting BHSI by 30% and charterage by 26%. In order to differentiate from previous studies and to find out the effect of short term lag, analysis was performed using monthly price data of major cargoes for Handysize bulk carriers, and meaningful results were derived that can predict monthly market conditions. This study can be helpful in predicting the short term market conditions for shipping companies that operate Handysize bulk carriers and concerned parties in the handysize chartering market.