• Journal of Korean Society of Forest Science
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• v.94 no.6
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• pp.446-452
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• 2005

In order to examine the natural distribution variations between groups of the Stewartia koreana, the leaf form characteristics of the investigation sites were analyzed by each group. As a result, the Mt. Kumsan group showed a smaller value in leaf length, width, area, and the number of veins, but not in the petiole length and serration number. Among each character, the coefficient of variation(CV) of the characters excluding petiole length and leaf area was in a comparatively narrow range, from 11.6~17.4%. On the other hand, the CV of petiole length and leaf area between the groups was 34.9% and 28.4% respectively. The CV of these characters within the group was also extraordinary- petiole length showed 29.5~42% and leaf area showed 27.7~40.7%. Also, the simple correlation analysis between 12 leaf characteristics showed that the correlation between leaf width and leaf area was high (r=0.975). The correlations between leaf length and leaf area, between leaf length and leaf width were 0.971 and 0.969, respectively. A negative correlation between angle of leaf base and ratio of leaf length to leaf width was discovered (r= -0.843), meaning that the ratio of leaf length to leaf width decreases as angle of leaf base increases. A cluster analysis was enforced among leaf characteristics of the selected group as a standard on the similarity of quantitative, qualitative measurements. The results showed that at a 0.4 distance level, the subjects could be classified into 4 groups. Group 1 was the Mt. Jogyesan and Mt. Kayasan group, group 2 was Mt. Paegunsan, group 3 was Mt. Unmunsan and Mt. Mudungsan, and group 4 was Mt. Kumsan. At a distance level of 0.6, the subjects were classified into two groups. Group 1 was the Mt. Ktimsan group and group 2 was Mt. Mudungsan, Unmunsan, Paegunsan, Kayasan, and Cogyesan. Especially the Mt. Kumsan group had the smallest value in the leaf characteristics of leaf length, width, area, and the number of veins, showing an obvious difference from the other five groups. There were five principal components that had a meaningful eigenvalue over 1.0 among the 12 extracted components. The explanatory power of the top two main components (leaf length and width) on the total variation was 52.7%. The explanatory power was 91.3% when all 5 main components were included.

• Journal of Korean Society of Forest Science
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• v.89 no.3
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• pp.310-322
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• 2000

The objectives of this study were to classify the types of vegetation in Pinus densiflora for. erecta stands. The study sites were located at Sokwang-Ri, Mt. Chungok(1,276m), Uljin, Mt. Kumma(1,017m) and Mt. Eungbong(1,267m). Two hundred thirty releves were classified and explained by phytosociological analysis(the method of ZM schools), and the results were summarized as follows. Pinus densiflora for. erecta stands were classified into Vaccinium koreanum community, Rhododendron micranthum community, Quercus dentata community, Acer pseudosieboldianum community, and Typical community. Quercus dentata community was divided into Festuca ovina group, Robinia pseudoacacia group, and Typical group, and Acer pseudosieboldianum community was divided into Hydrangea serrata for. acuminata group, Disporum smilacinum group, Magnolia sieboldii group, Carpinus laxiflora group, and Typical group, and Typical community was divided into Melampyrum roseum group and Typical group. And some groups were divided into 7 subgroups. Therefore, Pinus densiflora for. erecta stands had total of 16 vegetation units, out of those units, Vaccinium koreanum community distributed all over the studied areas. While Rhododendron micranthum community distributed mainly at Sokwang-Ri and Mt. Chungok. Therefore it was considered to be useful indicator in determining the range of afforestation and natural distribution of Pius densiflora for. erecta stands. The classified vegetation units were investigated by using of coincidence method. The results indicated that Quercus dentata community distributed mainly below 100 meters at the sea level, while other communities distributed above 350 meters at the sea level. According to the correlations between vegetation units and topography, Vaccinium koreanum and Rhododendron micranthum communities distributed mainly above middle slope areas, Quercus dentata community distributed mainly from lower slope to upper slope areas, Acer pseudosieboldianum community distributed mainly between valley and lower slope areas, and Typical community distributed mainly above upper slope areas. According to the correlations between vegetation units and 5 study areas, Quercus dentata community was distributed in the region of Uljin, and other communities were evenly distributed over other studied areas. According to the correlations between the units and aspects, all communities occurred all aspects, but most of the communities tended to be more distributed at south slopes than at north slopes, which meant that the relic stands of Pinus densiflora for. erecta were remained largely as patch phase status at south slopes.

• Resources Recycling
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• v.2 no.2
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• pp.27-38
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• 1993

In this study, we investigated the grinding and sedimentation(elutriation) process of the dusts for the effective separation of high purity iron and iron oxides. For characterization of the dust, particle size distribution and chemical composition, were examined. The results obtained in this study may be summarized as follows : 1. The converter CF(clarifier) dust of the Pohang 1st, 2nd steel making factory and EC(Evaporation Cooler), EP(Eltrostatic precititator) dust of the Kwangyang 2nd steel making factory are composed $\alpha$-Fe(21~50%), FeO(wustite)$Fe_3$$O_4$(magnetite), $Fe_2$$O_3$, CaO, $Al_2$$O_3$, $SiO_2$, and etc. 2. Pure iron has ductile characteristic in nature, particle size of the pure iron increase by increasing the grinding time. On the other hand, it is conformed that bo고 particles of hematite and magnetite become less than 325 mesh after 10 minutes grinding. 3. By applying the elutriation technique for the EC dust of the Kwangyang 2nd steel making factory, the iron powder of high content more than 99.17% of pure Fe was recovered with 37.8% yield at grinding time for 40 minutes. 4. By applying the elutriation technique for the CF dust of the Pohang 2nd steel making factory, the iron powder of high content more than 98.38% of pure Fe was recovered with 44.42% yield at grinding time for 40 minutes. 5. When magnetic separation was performed using plastic bonding magnet of 70 gauss, more than 98% Fe grade of iron powder was recovered in the size range +65 -200 mesh but the recovery of it was low.

• Journal of Haehwa Medicine
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• v.7 no.2
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• pp.609-620
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• 1999

Over the period between January 1997 and December 1998, herbal medicine was more than three times administered to the patients coming to Na dong gyu's Oriental Medical Clinic on account of the symptom of growth deficiency. According to radiological opinions about the patients providing cooperation for measuring their height and weight as well as their bone age every three months, it was found that the growth plates were not closed. A research was conducted for 200 children randomly selected of patients in prepuberty (they grew by less than 5cm a year before treatment at a age of 12years for female children and 14years for male children). As a result, the following conclusion was drawn: 1. The randomly selected subjects were made up of 116 male and 84 female children in terms of gender. The age direstribution was most 10 to 12 years in 86 children(34.00%), followed by 8-10 years(27.50%) and 12 to 14 years(19.50%). 2. Considering the distribution of sick children's parental height, the fathers of 141 children(70.50%) measured less than 170cm high, the subaverage height, while the mothers of 172 children(86%) measured less than 160cm high, the subaverage height. It was shown that sick childen's height was genetically influenced by their parents. 3. Children patients's weight at a time of birth was most 3.1-3.5kg for 85 children(44%) and less than 2.5kg which came under the range of growth dificiency for 19 children(9.5%). 4. The highest proportian of the children patients with growth dificiency(56.33%) had the symptom of digestive disorders, of which 77 children patients(18.78%) had anorexia, 16.59% of children patients had the high level of respiratory disorders. Both the digestive disorder and the respiratory disorder put together, they had the high rate of 72.92%. Therefore, this indicates that both the digestive disorder and the respiratory disorder have a great effect on children's growth dificiency. 10.74% of chilren patients were shown to have allergic disorders, which indicates that they also exert an effect on growth deficiency. Specifically, 7.07% of the children patients had the high level of obesity, which shows that an excessive uptake of nutrition may rather induce children to have growth dificiency though an appropriate amount of nutritional uptake is necessary. 5. Comparing their bone age and their chronological age, 58 children patients(29.00%) showed that they were the same at the highest percent. 79 children patients(39.50%) showed that thier bone age was lower than their chronological age. And 63 children patients(31.50%) showed that their bone age was higher than their chronological age. 6. As regards the prescription administered to children patients for treating their growth dificiency, Growth tang A related to the kidney, the congenital factor, of the causes for growth dificiency in traditional Oriental Medicine was administered to 108 children patients(54%), whereas the Growth tang B related to the spleen, the acquired factor, was administered to 92 children patients(46%). 7. 116 male children patients with growth dificiency had the average value of growth for one year before treatment, 4.39cm, while 84 female children patients had the average value of growth for one year before treatment, 4.24cm. A total of 200 children had the average value of growth for one year before treatment, 4.33cm. The annual average value of growth in growth curve surveyed by the Korea Pediatrics Society was 5.79cm. Compared to this value, the one year average value of growth for 108 male and female children patients taking Growth tang A was shown be 8.44cm, which indicates a greater growth by 4.12cm(95.37%) in comparison with the average value of growth before treatment, 4.32cm, and a greater growth by 2.65cm(45.77%) compared to 5.79cm, the average value of growth in growth curve surveyed by the Korea Pediatrics Society. Also, the average value of growth before treatment for 92 male and female children patients taking Growth tang B was shown to be 8.47cm, which indicates a greater increase by 4.15cm(96.06%) compared to 4.32cm, the average value of growth before treatment and a greater increase by 2.67cm(46.29%) in comparison with 5.79cm, the average value of growth in growth curve surveyed by the Korea Pediatrics Society. Considering the average value of growth for male and female children patients taking Growth tang A and B, it was shown to be 8.46cm, which indicates a greater increase by 4.14cm(95.81%) compared to 4.32cm, the average value of growth before treatment, and a greater increase by 2.67cm(46.11%) compared to 5.79cm, the average value of growth in growth curve surveyed by the Korea Pediatrics Society.

• Journal of the Society of Naval Architects of Korea
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• v.28 no.2
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• pp.52-68
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• 1991

A new propeller series is developed using the newly developed blade section(KH18 section) which behaves better cavitation characteristics and higher lift-drag ratio at wide range of angle-of-attack. The pitch and camber distributions are disigned in order to have the same radial and chordwise loading distribution with the selected circumferentially averaged wake input. Since the geometries of the series propeller, such as chord length, thickness, skew and rate distribations, are selected by regression of the recent full scale propeller geometric data, the performance prediction of a propeller at preliminary design stage can be mure realistic. Number of blades of the series propellers is 4 and the expanded blade area ratios are 0.3, 0.45, 0.6 and 0.75. Mean pitch ratios are selected as 0.5, 0.65, 0.8, 0.75 and 1.1 for each expanded area ratio. The new propeller series is composed of 20 propellers and is named as KD(KRISO-DAEWOO) propeller series. Propeller open water tests are performed at the experimental towing tank, and the cavitation observation tests and fluctuating pressure measurements are carried out at the cavitation tunnel of KRISO. $B_{P}-\delta$ curves, which can be used to select the optimum propeller diameter at the preliminary design stage, are derived from a regression analysis of the propeller often water test results. The KD-cavitation chart is derived from the cavitation observation test results by choosing the local maximum lift coefficient and the local cavitation number as parameters. The caviy extent of a propeller can be predicted more accurately by using the KD-cavitation chart at a preliminary design stage, since it is derived from the results of the cavitation observation tests in the selected ship's wake, whereas the existing cavitation charts, such as the Burrill's cavitation chart, are derived from the test results in uniform flow.

• Tuberculosis and Respiratory Diseases
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• v.48 no.1
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• pp.45-53
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• 2000

Background: The literature on variations of rib is limited. Very little has been written in the radiological journal of this country on the subject. It seemed of interest to investigate the nature and incidence of congenital variations in a series of routine chest roentgenograms. The topic of rib variations has not been covered extensively in the radiological journals in Korea. This has presented an opportunity to investigate the nature, type, shape and incidences of congenital rib variations in normal Korean adults from a series of routine roentgenograms. Methods: Chest radiographs of 5,000 adults, who visited our hospital for a routine check-up or for employment physical examinations from January 1996 to September 1998, were consecutively reviewed. The sex distribution consisted of 2,827 male males and 2,173 female females(ratio of 1.3:1) with the age range aged between 19 and 65 years(mean age: 34.6 years) were included. The chest PAs were analyzed for the presence, type, location, and shape of the rib variations. From this data the incidence of each type of variations was calculated. Results: Seventy-six of the 5,000 adults(1.52%), 63 male(2.23%) and 13 female(0.6%), showed 88 cases of rib variation(Table 1). The most common variation was the bifid rib(n=35), followed by hypoplasia of the rib(n=22), flaring of the rib(n=18), bridging of the ribs(n=7), cervical ribs(n=3), and fusion of between ribs(n=3)(Table 2). The bifid rib(Table 1) was found most frequent in the right fourth rib(12/35, 34.3%), followed by the left fifth rib(6/35, 17.1%) and right third rib(6/35, 17.1%). Hypoplasia of the rib was common in first rib(20/22, 90.9%). Flaring of the rib was common at fourth rib(8/18, 44.4%, right and left combined), and bridging between ribs was common between first and second rib(3/7, 42.9%). Conclusion : The percentage of incidence of rib variations in adults was 1.52%. Bifid rib was the most common variation, followed by hypoplasia, flaring, bridging, cervical rib, and fusion of ribs, in decreasing order.

• KDI Journal of Economic Policy
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• v.12 no.2
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• pp.95-120
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• 1990

The underpricing of new shares of a firm that are offered to the public for the first time (initial offerings) is well known and has puzzled financial economists for a long time since it seems at odds with the optimal behavior of the owners of issuing firms. Past attempts by financial economists to explain this phenomenon have not been successful in the sense that the explanations given by them are either inconsistent with the equilibrium theory or implausible. Approaches by such authors as Welch or Allen and Faulhaber are no exceptions. In this paper, we develop a signalling model of capital investment to explain the underpricing phenomenon and also analyze the efficiency of investment. The model focuses on the information asymmetry between the owners of issuing firms and general investors. We consider a firm that has been owned and operated by a single owner and that has a profitable project but has no capital to develop it. The profit from the project depends on the capital invested in the project as well as a profitability parameter. The model also assumes that the financial market is represented by a single investor who maximizes the expected wealth. The owner has superior information as to the value of the firm to investors in the sense that it knows the true value of the parameter while investors have only a probability distribution about the parameter. The owner offers the representative investor a fraction of the ownership of the firm in return for a certain amount of investment in the firm. This offer condition is equivalent to the usual offer condition consisting of the number of issues to sell and the unit price of a share. Thus, the model is a signalling game. Using Kreps' criterion as the solution concept, we obtained an essentially unique separating equilibrium offer condition. Analysis of this separating equilibrium shows that the owner of the firm with high profitability chooses an offer condition that raises an amount of capital that is short of the amount that maximizes the potential profit from the project. It also reveals that the fraction of the ownership of the firm that the representative investor receives from the owner of the highly profitable firm in return for its investment has a value that exceeds the investment. In other words, the initial offering in the model is underpriced when the profitability of the firm is high. The source of underpricing and underinvestment is the signalling activity by the owner of the highly profitable firm who attempts to convince investors that his firm has a highly profitable project by choosing an offer condition that cannot be imitated by the owner of a firm with low profitability. Thus, we obtained two main results. First, underpricing is a result of a signalling activity by the owner of a firm with high profitability when there exists information asymmetry between the owner of the issuing firm and investors. Second, such information asymmetry also leads to underinvestment in a highly profitable project. Those results clearly show the underpricing entails underinvestment and that information asymmetry leads to a social cost as well as a private cost. The above results are quite general in the sense that they are based upon a neoclassical profit function and full rationality of economic agents. We believe that the results of this paper can be used as a basis for further research on the capital investment process. For instance, one can view the results of this paper as a subgame equilibrium in a larger game in which a firm chooses among diverse ways to raise capital. In addition, the method used in this paper can be used in analyzing a wide range of problems arising from information asymmetry that the Korean financial market faces.

• The Journal of Engineering Geology
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• v.14 no.1
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• pp.29-46
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• 2004

It is important to identify geometries of fracture that act as a conduit of fluid flow for characterization of ground water flow in fractured rock. Fracture geometries control hydraulic conductivity and stream lines in a rock mass. However, we have difficulties to acquire whole geometric data of fractures in a field scale because of discontinuous distribution of outcrops and impossibility of continuous collecting of subsurface data. Therefore, it is needed to develop a method to describe whole feature of a target fracture geometry. This study suggests a new approach to develop a method to characterize on the whole feature of a target fracture geometry based on the Fourier transform. After sampling of specimens along a target fracture from borehole cores, effective frequencies among roughness components were selected by the Fourier transform on each specimen. Then, the selected effective frequencies were averaged on each frequency. Because the averaged spectrum includes all the frequency profiles of each specimen, it shows the representative components of the fracture roughness of the target fracture. The inverse Fourier transform is conducted to reconstruct an averaged whole roughness feature after low pass filtering. The reconstructed roughness feature also shows the representative roughness of the target subsurface fracture including the geometrical characteristics of each specimen. It also means that overall roughness feature by scaling up of a fracture. In order to identify the characteristics of permeability coefficients along the target fracture, fracture models were constructed based on the reconstructed roughness feature. The computation of permeability coefficient was performed by the homogenization analysis that can calculate accurate permeability coefficients with full consideration of fracture geometry. The results show a range between $10^{-4}{\;}and{\;}10^{-3}{\;}cm/sec$, indicating reasonable values of permeability coefficient along a large fracture. This approach will be effectively applied to the analysis of permeability characteristics along a large fracture as well as identification of the whole feature of a fracture in a field scale.

• Cartoon and Animation Studies
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• s.39
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• pp.413-450
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• 2015

Although cartoons have been recognized for their great potential and value, they have failed to bloom in Korea. This is because wrong perception and irregular distribution of cartoons have been repeated for the last several years. Presently, however, cartoons are escaping from chronic problems they have had for long and welcoming splendid chances now. From the mid- and late-1990's, there have been large-scale events having cartoons as their theme, and social recognition on cartoons is becoming more and more positive. Their contents are diversified, readers are increased, and they are escaping from stereotypes through harmony with other media. Lately, either large or small exhibitions for cartoons are being planned, and Korean cartoons are going overseas and producing exhibitions there. Particularly, visitors' appreciative eye is getting keener, and they begin to see them not as a genre underestimated as low culture like in the past but as a kind of art on which independent research is being actively conducted. One of the biggest factors that have allowed cartoons to be positioned as visual art is the form of exhibitions that combine them with other genres artistically. Especially the cartoon exhibitions being held these days are aggressively introducing various elements of the cartoon genre through the medium of exhibitions not just as a mere tool of seeing to help understand cartoon writers or works. The genre of cartoons is now regarded as an active subject that can reflect its own unique essence in this rapidly changing cultural environment and extend the range of it itself. The latest cartoon exhibitions are characterized by trans-genre and complex aspects in terms of their direction or organization according to the contents, space, or theme. This trend of cartoon exhibitions implies that they are subdividing, analyzing, and planning various factors not in a horizontal way that was centered around image as in the past. It means that cartoon exhibitions are evolving as a form of mobilizing, combining, and reproducing various methods. Although a number of cartoon exhibitions are being held with a variety of themes, there is still lack of research on cartoon exhibitions concerning their forms and contents. Therefore, this researcher sees cartoon exhibitions as a factor that allows cartoons to escape from negative recognition and examines various cartoon exhibitions, from Seoul International Cartoon Animation Festival to the ones that are recently held, to figure out the meaning of Korean cartoon exhibitions. Furthermore, this researcher will find out the factors of planning and popularity in international exhibitions or personal cartoon exhibitions being presently held and figure out new directions and potentials for Korean cartoon exhibitions based on that. To meet the needs of visitors whose expectations have become even higher, it is needed to try not just previous methods but experimental and original planning as well constantly. To realize that, it is necessary to keep providing a field of opportunity where cartoon works, cartoon writers, and visitors can communicate as in an exhibition. It is expected that this study will trigger research on cartoon exhibitions to be performed multilaterally and produce new discourse on cartoon exhibitions afterwards.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.1
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• pp.47-58
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• 2002

Much of the plastic film house soils in the southern part of the Korean peninsula are managed using a upland-paddy rotation culture system (hereafter, RS) to prevent salt accumulation in soil. However, information on the effects of RS on soil properties and environmental conservation is limited. In order to determine the effects of RS on soil properties, 22 fields under RS and 20 fields under a non-rotation system (hereafter, NRS) in plastic film houses were selected in Chinju, in southern Korea, and the P distribution characteristics were investigated, including the chemical properties. The RS contributed to the removal of water-soluble salts in the surface layer and to the redistribution of organic matter evenly in the soil profile. In the AP horizon, available phosphorus levels were $1,611mg\;kg^{-1}$ in RS and $1,789mg\;kg^{-1}$ in NRS, which markedly exceeds the optimum range for plant cultivation. Total P was lower in RS (average $4,593mg\;kg^{-1}$) than in NRS (average $5,440mg\;kg^{-1}$) and this decrease was taken to be an effect of RS. Inorganic P was the predominant form of P in both systems, followed by organic P and residual P. A soil profile showed that total and inorganic P concentrations decreased with depth in both systems. However, organic P increased withdepth in RS, which was in contrast to that noted in NRS. The increase in organic P with depth in RS implied that organically rather than inorganically derived phosphate moved through the soil. The concentrations of water-soluble P, Ca-P and Al-P were higher in NRS than in RS soil profiles, but the Fe-P concentration was higher in RS than in NRS, which might be affected by the anaerobic conditions found in paddy soils. In both systems, the Al-P form of extractable P predominated in the surface layer, followed by Ca-P, Fe-P and water-soluble P. With increasing depth, the composition rate of Ca-P to extractable P decreased to less than 10% in the 60-70cm depth, as Fe-P dominated at this level. The content of water-soluble P, potentially the main source of eutrophication, was higher in NRS than in RS. These results indicated that the RS used in plastic film houses contributed to the removal of water-soluble salts but only slightly decreased the phosphate concentration.