• KOREAN JOURNAL OF CROP SCIENCE
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• v.4 no.1
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• pp.93-95
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• 1968

The importance of leaf area as related to transpiration and photosynthesis is generally recognized. In general, a compound leaf of soybean consist of one main leaflet and two side leaflets from each node of the stem. Takahashi and Fukuyama (1919) classified soybeans into three types, namely the long leaf type, round leaf type, and intermediate type, in which the last one had round leaves at the base and long leaves in the upper part of the stem. Nagai (1925) and Takahashi (1935). dealt with the genetics of the leaf form and association with other characters. The closely relationships, the correlation coefficients from 0.64 to 0.73, were shown between the leaf area and the soybean yield in the experiments by Nagai (1942). Nagata (1950) also tested the varietal differences of the variation of leaf length and its ratio to the leaf width on the nodes of stem, and finally divided varieties into five types. Three methods of measuring area of strawberry leaves were used by Darrow (1932). The first involved determining a factor to be used with length or length ${\times}$width measurements. The second method involved placing leaves on pieces of cardboard of known area cut to the shape of the leaves. Direct use of the planimeter on intact leaves was Darrow's third method. Miller (1938) enumerated several methods to determine the leaf surface area in plants, some of which were extremely laborious and required removing leaves from plants. They included tracing outlines of leaves on paper and measuring the enclosed area with a planimeter or cutting out the traced areas and comparing the weights obtained with the weight of a known paper. Another method involved placing the form of the leaf on sensitized paper with the area being determined by measuring or weighing as above. Miller further stated that the photoelectric cell can also be utilized to estitmate leaf area. Working with field beans, Davis (1940) found that 0.004517 (length ${\times}$ width) of the center leaflet was the most nearly accurate of four methods attempted. A simple procedure to measure leaf area in corn was devised 1 y Montgomery (1911) and used by Kiesselbach (1950). The formula was length ${\times}$ width ${\times}$ 0.75. Stickler et al. (1961) have successfully used length times width ${\times}$ 0.747 to estimate area of grain sorghum leaves. Bhan and Pande(1966) has also used length ${\times}$ width ${\times}$ 0.802 to determine leaf area of rice varieties. The main objectives of the present investigation were to develop an accurate, rapid method to determine leaf area in soybean varieties and to examine certain data associated with leaf area determinations.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.4 no.3
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• pp.215-225
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• 1999

To study the vertical variations of major elements, trace elements and rare earth elements(REEs) contents in deep-sea sediments, six cores from Korea Deep-sea Environmental Study area(KODES) were analyzed. Topmost sediment layers of KODES area are divided into two Units; brown-colored and peneliquid Unit I and pale brown-colored and relatively solidified Unit II. Contents of major elements, REEs, Cu, Sr and Rb in each Unit are almost same, while contents of Mn, Ni and Co in Unit I are two or three times higher than those in Unit II. R-mode factor analysis represents that surface sediments are composed of alumino-silicate phase (AI-Ti-K-Mg-Fe-Rb-Ce), apatite phase (Ca-P-Cu-Sr-Trivalent Rare Earth Elements) and Mn-oxide phase(Mn-Ni-Co). Factor scores in silicate and apatite phases in each Unit are nearly same, whereas those in Mn-oxide phase in Unit I is higher than those in Unit II. While NilCu ratio in Unit I is two times higher than that in Unit II. We interprete the geochemical fractionation of Ni and Cu as a result that Ni can be remobilized in oxygen-depleted micro-environment in Units I and II and then easily reprecipitated in Unit I, while most of Cu supplied together with organic material is decomposed mostly in Unit I and sorbed into apatite.

• The Journal of Korean Academy of Prosthodontics
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• v.46 no.1
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• pp.53-64
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• 2008

Statement of problem: Peri-implant marginal bone loss is an important factor that affects the success of implants in esthetics and function. Various efforts have been made to reduce this bone loss by improving implant design and surface texture. Previous studies have shown that early marginal bone loss is affected by implant neck designs. Purpose: The purpose of this study was to examine the influence of laser microtexturing of implant collar on peri-implant marginal bone loss. Materials and methods: Radiographical marginal bone loss was examined in patients treated with implant-supported fixed partial dentures. Marginal bone level was examined with 101 implant fixtures installed in 53 patients at three periods(at the time of implantation, prosthetic treatment and 6-month after loading). Four types of implants were examined. The differences of bone loss between implants(ITI standard) with enough biologic width and implants(ITI esthetic plus, Silhouette IC, Silhouette IC Laser-$Lok^{TM}$) with insufficient biologic width have been compared. Resorption angles were examined at the time of prosthetic delivery and 6-month after loading. Results and Conclusion: Within the limitation of this study, the following results were drawn. 1. The marginal bone loss of ITI standard and Silhouette IC Laser-$Lok^{TM}$ was less than that of ITI esthetic plus and Silhouette IC(P<0.05). The marginal bone loss between ITI standard and Silhouette IC Laser-$Lok^{TM}$ had no significant statistical difference(P>0.05). There was no significant statistical difference between marginal bone loss of ITI esthetic plus and Silhouette IC(P>0.05). 2. There was no significant difference in marginal bone loss between maxilla and mandible(P>0.05). 3. There was no significant difference in resorption angle among four types of implants(P>0.05). The marginal bone of implants with supracrestal collar design of less than that of biologic width had resorbed more than those with sufficient collar length. The roughness and laser microtexturing of implant neck seem to affect these results. If an implant with collar length of biologic width, exposure of fixture is a possible complication especially in the anterior regions of dentition that demand high esthetics. Short smooth neck implant are often recommended in these areas which may lack the distance between microgap and the marginal bone level. In these cases, the preservation of marginal bone must be put into consideration. From the result of this study, it may be concluded that laser microtexturing of implant neck is helpful in the preservation of marginal bone.

• Atmosphere
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• v.23 no.3
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• pp.283-291
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• 2013

This study investigates the changes in the atmosphere-ocean interactions over the South China Sea (SCS) by analyzing their variables in the period of 1979~2011 during the boreal summer (June-July-August). It is found that a simultaneous correlation coefficient between sea surface temperature (SST) and precipitation over SCS during summer is significantly changed before and after the late-1990s. That is, the variation of precipitation over SCS is negatively (positively) correlated with the SST variations before (after) the late-1990s. Our further correlation analysis indicates that the atmospheric forcing of the SST is dominant before the late-1990s accompanying with wind-evaporation feedback and cloud-radiation feedback. After the late-1990s, in contrast, the SST forcing of the atmosphere through the latent heat flux from the ocean to the atmosphere is dominant. It is found that the change in the relationship of atmosphere-ocean interactions over SCS are associated with the changes in the relationship with Northeast Asian summer precipitation. In particular, a simultaneous correlation coefficient between the precipitation over SCS and Northeast Asia becomes stronger during after the late-1990s than before the late-1990s. We argue that the increase of the SST forcing of the atmosphere over SCS may lead a direct relationship of precipitation variations between SCS and Northeast Asia after the late-1990s.

• Journal of the Mineralogical Society of Korea
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• v.19 no.4 s.50
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• pp.277-289
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• 2006

This study was carried out to find a new material having high removal efficiency for the harmful red tide. C. polykrikoides grow very fast and accumulate into dense and visible patches near the surface of the seawater ('Water bloom'). Some mineral medicines and Hwangto (reddish soil consist of clay minerals and Fe-oxides) were used in this study to remove C. polykrikoides. The pre-determined sprinkling ratio of mineral vs. seawater which contains approximately 5,000 cells/mL of C. polykrikoides was 10 g/L. In order to quantify the removal efficiency, the density of living cells was measured by counting with the Intervals of 0, 10, 30, and 60 minutes after sprinkling. Five Hwangtos feom different localities were examined in this study. It is found that a material with a high concentration of Fe and Al was the most effective to remove C. polykrikoides. After the sprinkling of the Hwangto showing the best removal efficiency in the test, 99% of total algaes were found to be eliminated within 60 minutes. Jeokeokji showed the highest removal efficiency among clay mineral medicines(92% removal efficiency after 60 minutes), and the rests in decreasing order are as follows: Gamto (91%) > Baekseokji (89%) > Hydromica (81%). In addition, Fe-oxide mineral medicine similarly looking as fine-grained earthy Daejaseok showed 100% removal efficiencyafter 30 minutes, and Wooyoeryang, 95% after 60 minutes. It is noted that even little addition (1 g/L) of Daejaseok, 10% of Hwangto concentration into seawater showed the removal efficiency of 100% after 60 minutes. From the results, it could be concluded that the fine-grained earthy Daejaseok was the most effective natural mineral medicine to remove the C. polykrikoides from seawater. Under the microscope the removal mechanism was found to be activated in the following order: adsorption, swelling of chain colony, chain colony crisis and algaecide.

• Korean Journal of Materials Research
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• v.6 no.7
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• pp.700-708
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• 1996

Electroless plating technique was utilized to flip chip bonding to improve surface mount characteristics. Each step of plating procedure was studied in terms pf pH, plating temperature and plating time. Al patterned 4 inch Si wafers were used as substrstes and zincate was used as an activation solution. Heat treatment was carried out for all the specimens in the temperature range from room temperature to $400^{\circ}C$ for $30^{\circ}C$ minutes in a vacuum furnace. Homogeneous distribution of Zn particles of size was obtained by the zincate treatment with pH 13 ~ 13.5, solution concentration of 15 ~ 25% at room temperature. The plating rates for both Ni-P and Au electroless plating steps increased with increasing the plating temperature and pH. The main crystallization planes of the plated Au were found to be (111) a pH 7 and (200) and (111) at pH 9 independent of the annealing temperature.

• Applied Microscopy
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• v.33 no.2
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• pp.145-154
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• 2003

The present study was designed to demonstrate ionic zinc in the rat nasal mucosa by means of zinc selenium autometallography ($ZnSe^{AMG}$). Rats were given sodium selenide either intraperitoneally (i.p) or intranasally (i.n). Prior to the i.n. administration the rats were anesthetized with pentobarbital sodium (30 mg/kg, i.p.). A thin plastic tube coupled to a Hamilton syringe was then inserted into the right nostril and $10{\mu}l$ of the solution was instilled. For the i.p. administration non-anesthetized rats were given $100{\mu}l$ of the sodium selenide solution (10 mg/kg). Control rats were instilled with saline. After 2 hrs survival, the rats were anaesthetized and transcardially perfused with 3% glutaraldehyde. The olfactory area was removed and put into same fixative. The nose was then sectioned ($30{\mu}m$) horizontally, autometallography (AMG) was performed according to Danscher et al. (1997). After silver enhancement, fine AMG grains were scattered in the whole length of the olfactory epithelium containing olfactory receptor neurons, sustentacular and basal cells. However, much higher concentration of the AMG grains occupied near the surface and in the basal region of the olfactory epithelium. Both groups of i.p. and i.n. administration showed almost same level in the concentration of the AMG grains. In i.n. group, few AMG grains were also found in olfactory nerves of the lamina propria, suggesting zinc transport into the olfactory bulb via olfactory axons. At the electron microscopic level, the AMG grains were most entirely found in the supporting cells of the olfactory epithelium, and they were mostly localized in lysosome-like organelles. The i.n. group showed various signs of tissue damage of the olfactory mucosa, where dense concentration of AMG grains were localized at crystalloid structures. The present study demonstrated dense population of ionic zinc in the rat olfactory epithelium. zinc may play a role in the olfactory functioin and in the pathogenesis of the neurodegerative disorders affecting nose.

• Economic and Environmental Geology
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• v.25 no.3
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• pp.259-273
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• 1992

The Seongsan mine is one of the largest dickite deposits in the southwestern part of the Korean Peninsula. The main constithent minerals of the ore are dickite and quartz with accessory alunite, kaolinite and sericite. The geology around the Seongsan mine consists mainly of the late Cretaceous felsic volcanic rocks. In the studied area, these rocks make a synclinal structure with an axis of E-W direction plunging to the east. Most of the felsic volcanic rocks have undergone extensive hydrothermal alteration. The hydrothermally altered rocks can be classified into the following zones: Dickite, Dickite-Quartz, Quartz, Sericite, Albite and Chlorite zones, from the center to the margin of the alteration mass. Such zonal arrangement of altered rocks suggests that the country rocks, most of which are upper part of the rhyolite and welded tuff, were altered by strongly acid hydrothermal solutions. It is reasonable to consider that initial gas and solution containing $H_2S$ and other compounds were oxidized near the surface, and formed hydrothermal sulfuric acid solutions. The mineralogical and chemical changes of the altered rocks were investigated using various methods, and chemical composition of fifty-six samples of the altered rocks were obtained by wet chemical analysis and X.R.F. methods. On the basis of these analyses, it was found that some components such as $SiO_2$, $Al_2O_3$, $Fe_2O_3$, CaO, MgO, $K_2O$, $Na_2O$ and $TiO_2$ were mobilized considerably from the original rocks. The formation temperature of the deposits was estimated as higher than $200^{\circ}C$ from fluid inclusion study of samples taken from the Quartz zone. On the basis of the chemical composition data on rocks and minerals and estimated temperatures, the hydrothermal solutions responsible for the formation of the Seongsan dickite deposits were estimated to have the composition: $m_{K^+}=0.003$, $m_{Na^+}=0.097$, $m_{SiO_2(aq.)}=0.008$ and pH=5.0, here "m" represents the molality (mole/kg $H_2O$).

• Korean Journal of Agricultural and Forest Meteorology
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• v.2 no.2
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• pp.47-61
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• 2000

Agroclimatic zoning was done for paddy rice culture in North Korea based on a simulation experiment. Daily weather data for the experiment were generated by 3 steps consisting of spatial interpolation based on topoclimatological relationships, zonal summarization of grid cell values, and conversion of monthly climate data to daily weather data. Regression models for monthly climatological temperature estimation were derived from a statistical procedure using monthly averages of 51 standard weather stations in South and North Korea (1981-1994) and their spatial variables such as latitude, altitude, distance from the coast, sloping angle, and aspect-dependent field of view (openness). Selected models (0.4 to 1.6$^{\circ}C$ RMSE) were applied to the generation of monthly temperature surface over the entire North Korean territory on 1 km$\times$l km grid spacing. Monthly precipitation data were prepared by a procedure described in Yun (2000). Solar radiation data for 27 North Korean stations were reproduced by applying a relationship found in South Korea ([Solar Radiation, MJ m$^{-2}$ day$^{-1}$ ] =0.344 + 0.4756 [Extraterrestrial Solar Irradiance) + 0.0299 [Openness toward south, 0 - 255) - 1.307 [Cloud amount, 0 - 10) - 0.01 [Relative humidity, %), $r^2$=0.92, RMSE = 0.95 ). Monthly solar irradiance data of 27 points calculated from the reproduced data set were converted to 1 km$\times$1 km grid data by inverse distance weighted interpolation. The grid cell values of monthly temperature, solar radiation, and precipitation were summed up to represent corresponding county, which will serve as a land unit for the growth simulation. Finally, we randomly generated daily maximum and minimum temperature, solar irradiance and precipitation data for 30 years from the monthly climatic data for each county based on a statistical method suggested by Pickering et a1. (1994). CERES-rice, a rice growth simulation model, was tuned to accommodate agronomic characteristics of major North Korean cultivars based on observed phenological and yield data at two sites in South Korea during 1995~1998. Daily weather data were fed into the model to simulate the crop status at 183 counties in North Korea for 30 years. Results were analyzed with respect to spatial and temporal variation in yield and maturity, and used to score the suitability of the county for paddy rice culture.

• Journal of Chest Surgery
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• v.29 no.12
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• pp.1306-1315
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• 1996

This study reviewed the changes of hemodynamlcs and centrAl pulmonary artery dimension in 54 patients who underwent bidirectional cavopulmonary shunt(BCPS) between February 1992 and December 1995 at Seoul National University Childrell's Hospital. Ag and body weight of patients averaged 36.8 $\pm$ 37.7 months and 8.0$\pm$3.0 kg, respectively Eightynine percent of patients had more than 2 violations of the risk factors for Fontan operation, resulting overall hospital mortality of 16.6%(9154). Serial hemodynamic and anglographic examinations before and mean 16.3 $\pm$ 14.3 months iirter BCPS were compared. The arterial oxygen saturation improved from a preoperative value of 71 9: 10.1 % to 79.H $\pm$ 8. 5% (n:4), p<0.05). The values of arterial oxygen saturation were lower as the age of the patients with BCPS in place was older(n=22, R'=0.341, p=0.004). A mean pulmonary artery pressure and pulmonary vascular resistance reduced from 31 $\pm$17 to 1).5$\pm$3.SmmHg(n=22, p<0.05) and from ).2$\pm$2.1 to 2.3$\pm$2.7 unit (n=7. p>0.05), respectively. Follow-up study showed a significant Increase of absolute values of ipsilateral pulmoanry artery (n: 14, p<0.05), but no change of contralateral pulmonary artreries (n: 14. p=not significant(HSI). However, there w re significant decreases in diameters of both ipsilateral and contralateral pulmonary arteries standardized by patients' body surface areas(16.8% decrease, n: 14, p< 0. 05 for ipsilatreal, 25.1%, n=14, p<0.05 for contralateral). Pulmonary artery indices for cross sectional areas of both pulmonary arterises decreased 9.3 $\pm$ 13.8% with showing a trend of more decrease as the follow-up duration was longer, We conclude that the bidirectional cavopulmonary shunt provide an excellent.