• Economic and Environmental Geology
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• v.36 no.4
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• pp.305-312
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• 2003

This study was performed to delineate the subsurface geology, geologic structure, and distribution pattern of the Palgongsan granitic body, and to reveal the relationship between the Kyeongsang basin and Yongnam massif by gravity survey. The study area is located between the latitude of 35$^{\circ}$45'-36$^{\circ}$21'N and longitude of 128$^{\circ}$15'-129$^{\circ}$00'E. Total of 966 gravity data measured by Seoul National University, KlGAM(Korea Institute of Geology, Mining ＆ Materials), Pusan National University and Yonsei University were used. The Bouguer gravity anomaly in the study area ranges from -12.88 to 26.01 mgal with a mean value of 11.27 mgal. A very low anomaly zone is located in the Yongnam massif in west of the study area. The anomaly value increases going from west to east. A low anomaly distribution in Palgongsan granite and Yongnam massif is interpreted as the effect of their lower density than that of Kyeongsang Super Group. Power spectrum analysis is applied to evaluate the average depth of basement the Kyeongsang Basin and Conrad discontinuity from gravity anomaly. The average depths of density discontinuities are calculated 10.45 km and 4.9 km, and these are interpreted as Conrad discontinuity and depth of basement of the Kyeongsang Basin, respectively. The depth of Palgongsan granite is derived by means of 2-dimensional modeling and it decreases gradually toward the east. The gravity anomaly east of the study area decreases abruptly due to Shingryeong fault and Nogosan ring fault. Two deepest and sharp roots of Palgongsan granite are recognized by 2-dimensional modeling of each profiles. The depths of those roots are 5.3 km on a profile AA' and 7 km on a profile BB' which is the maximum depth of Palgongsan granite. Small granitic bodies are also seen to be intruded around the Palgongsan granite. The root of Palgongsan granite is shown by 3-dimensional analysis based on the interpolation of 2-dimensional modeling along each profiles to exist in the southwest vicinity of Palgongsan granite. The total volume of Palgongsan granite is approximately 31.211 $Km^3$.

• Korean Journal of Environment and Ecology
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• v.27 no.5
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• pp.561-570
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• 2013

Organic carbon distribution and carbon budget of a Pinus densiflora forest in the Songgye valley of Mt. Worak National Park were investigated. Carbon in above and below ground standing biomass, litter layer, and soil organic carbon were measured from May 2011 through April 2012. For the estimation of carbon budget, soil respiration was measured. The amount of carbon allocated to above and below ground biomass was 52.25 and 14.52 ton C $ha^{-1}$. Amount of organic carbon in annual litterfall was 4.71 ton C $ha^{-1}$. Amount of organic carbon within 50cm soil depth was 58.56 ton C $ha^{-1}$ 50cm-$depth^{-1}$. Total amount of organic carbon in this Pinus densiflora forest was estimated to 130.04 ton C $ha^{-1}$. Amount of organic carbon in tree layer, shrub and herb layer was 4.12, 0.10 and 0.04 ton C $ha^{-1}yr^{-1}$ and total amount of organic carbon was 4.26 ton C $ha^{-1}yr^{-1}$. Amount of organic carbon returned to the forest via litterfall was 1.62 ton C $ha^{-1}yr^{-1}$. The amount of carbon evolved through soil respiration was 6.25 ton C $ha^{-1}yr^{-1}$. The amount of carbon evolved through microbial respiration and root respiration was 3.19 and 3.06 ton C $ha^{-1}yr^{-1}$. The amount of organic carbon absorbed from the atmosphere of this Pinus densiflora forest was 1.07 ton C $ha^{-1}yr^{-1}$ when it was estimated from the difference between Net Primary Production and microbial respiration.

• Proceedings of the Ginseng society Conference
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• 1978.09a
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• pp.149-157
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• 1978

Ginseng is the English common name for the species in the genus Panax. This article gives a broad botanical review including the morphological characteristics, ecological amplitude, and the ethnobotanical aspect of the genus Panax. The species of Panax are adapted for life in rich loose soil of partially shaded forest floor with the deciduous trees such as linden, oak, maple, ash, alder, birch, beech, hickory, etc. forming the canopy. Like their associated trees, all ginsengs are deciduous. They require annual climatic changes, plenty of water in summer, and a period of dormancy in winter. The plant body of ginseng consists of an underground rhizome and an aerial shoot. The rhizome has a terminal bud, prominent leafscars and a fleshy root in some species. It is perennial. The aerial shoot is herbaceous and annual. It consists of a single slender stem with a whorl of digitately compound leaves and a terminal umbel bearing fleshy red fruits after flowering. The yearly cycle of death and renascence of the aerial shoot is a natural phenomenon in ginseng. The species of Panax occur in eastern North America and eastern Asia, including the eastern portion of the Himalayan region. Such a bicentric generic distributional pattern indicates a close floristic relationship of the eastern sides of two great continental masses in the northern hemisphere. It is well documented that genera with this type of disjunct distribution are of great antiquity. Many of them have fossil remains in Tertiary deposits. In this respect, the species of Panax may be regarded as living fossils. The distribution of the species, and the center of morphological diversification are explained with maps and other illustrations. Chemical constituents confirm the conclusion derived from morphological characters that eastern Asia is the center of species concentration of Panax. In eastern North America two species occur between longitude $70^{\circ}-97^{\circ}$ Wand latitude $34^{\circ}-47^{\circ}$ N. In eastern Asia the range of the genus extends from longitude $85^{\circ}$ E in Nepal to $140^{\circ}$ E in Japan, and from latitude $22^{\circ}$ N in the hills of Tonkin of North Vietnam to $48^{\circ}$ N in eastern Siberia. The species in eastern North America all have fleshy roots, and many of the species in eastern Asia have creeping stolons with enlarged nodes or stout horizontal rhizomes as storage organs in place of fleshy roots. People living in close harmony with nature in the homeland of various species of Panax have used the stout rhizomes or the fleshy roots of different wild forms of ginseng for medicine since time immemorial. Those who live in the center morphological diversity are specific both in the application of names for the identification of species in their communication and in the use of different roots as remedies to relieve pain, to cure diseases, or to correct physiological disorders. Now, natural resources of wild plants with medicinal virtue are extremely limited. In order to meet the market demand, three species have been intensively cultivated in limited areas. These species are American ginseng (P. quinquefolius) in northeastern United States, ginseng (P. ginseng) in northeastern Asia, particularly in Korea, and Sanchi (P. wangianus) in southwestern China, especially in Yunnan. At present hybridization and selection for better quality, higher yield, and more effective chemical contents have not received due attention in ginseng culture. Proper steps in this direction should be taken immediately, so that our generation may create a richer legacy to hand down to the future. Meanwhile, all wild plants of all species in all lands should be declared as endangered taxa, and they should be protected from further uprooting so that a. fuller gene pool may be conserved for the. genus Panax.

• Korean Journal of Soil Science and Fertilizer
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• v.3 no.1
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• pp.49-54
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• 1970

In an effort of determine the metabolism and bio-synthesis of nitrogen, was studied at variance of souble nitrogens, free amino acids and total alcohol soluble amino acids during the growth of younger soybean plants, and saybean divides into cotyledon and embryonic organ (shoot and root system) in this experiment. 1. In the soluble nitrogen of soybean, ratio of increase and decrease in the amino acids of them was displayed the near phenomena both cotyledon and embryonic organ of soybean. But, in the 17th days after seed germination, that is the developmeatal stage of adult leaf of soybeans, was appear the maximum value. It has been suggested that the stage of first half period of growth as boundary the stage of adult leaf development which indicated clear morphologically, at the younger soybean plants, is the step that nitrogen assimilation. 2. It was investigated the amino acids of seventeen kinds in the seed state, but at the third days after seed germination, was investigated the amino acids of nineteen kinds. Ultimately, it appears the translocation from cotyledon to embryonic organ in the distribution of amino acid, the nineth day which differentiation begining day of embryonic organ, then after, it happen the variation of number of inspected amino acid in the cotyledon and embryonic organ but only the variance changes in the distribution and quantitative aspects. Especially, the most conspicuous fact was indicated the accumulation of Asparagine, that is the phenomena of Asparagine-accumulation was constitute, not with standing no fertilization from outside. It may be concluded from the results of this investigation that the difference of special phenomena of soybean from the embryo of other plans. 3. In the initial stage of differentiation at embryonic organ number of inspected amino acid was very few, and then, it was slightly appeared the increase-phenomena in the number of them. It was that the amino acid inspecting the initial stage was translocated from the cotyledon. It is suggested that the intermediate-metabolism of amino acid was constituted on the basis of above the result. 4. The phenomena of increase and decrease of total alcohol soluble amino acid were essentially identical to the water soluble amino acid of soybean, but it was appeared the severe difference of amounts in both of them.

• Korean Journal of Remote Sensing
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• v.14 no.1
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• pp.53-68
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• 1998

Observation of hydrometeors' behavior in the atmosphere is important to understand weather and climate. By conventional observations, we can get the distribution of water vapor at limited number of points on the earth. In this study, the precipitable water has been estimated from the split window channel data on GMS-5 based upon the technique developed by Chesters et al.(1983). To retrieve the precipitable water, water vapor absorption parameter depending on filter function of sensor has been derived using the regression analysis between the split window channel data and the radiosonde data observed at Osan, Pohang, Kwangiu and Cheju staions for 4 months. The air temperature of 700 hPa from the Global Spectral Model of Korea Meteorological Administration (GSM/KMA) has been used as mean air temperature for single layer radiation model. The retrieved precipitable water for the period from August 1996 through December 1996 are compared to radiosonde data. It is shown that the root mean square differences between radiosonde observations and the GMS-5 retrievals range from 0.65 g/$cm^2$ to 1.09 g/$cm^2$ with correlation coefficient of 0.46 on hourly basis. The monthly distribution of precipitable water from GMS-5 shows almost good representation in large scale. Precipitable water is produced 4 times a day at Korea Meteorological Administration in the form of grid point data with 0.5 degree lat./lon. resolution. The data can be used in the objective analysis for numerical weather prediction and to increase the accuracy of humidity analysis especially under clear sky condition. And also, the data is a useful complement to existing data set for climatological research. But it is necessary to get higher correlation between radiosonde observations and the GMS-5 retrievals for operational applications.

• Journal of the Korean Association of Geographic Information Studies
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• v.22 no.3
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• pp.21-36
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• 2019

Dead fuel moisture content is a key variable in fire danger rating as it affects fire ignition and behavior. This study evaluates simple regression models estimating the moisture content of standardized 10-h fuel stick (10-h FMC) at three sites with different characteristics(urban and outside/inside the forest). Equilibrium moisture content (EMC) was used as an independent variable, and in-situ measured 10-h FMC was used as a dependent variable and validation data. 10-h FMC spatial distribution maps were created for dates with the most frequent fire occurrence during 2013-2018. Also, 10-h FMC values of the dates were analyzed to investigate under which 10-h FMC condition forest fire is likely to occur. As the results, fitted equations could explain considerable part of the variance in 10-h FMC (62~78%). Compared to the validation data, the models performed well with R2 ranged from 0.53 to 0.68, root mean squared error (RMSE) ranged from 2.52% to 3.43%, and bias ranged from -0.41% to 1.10%. When the 10-h FMC model fitted for one site was applied to the other sites, $R^2$ was maintained as the same while RMSE and bias increased up to 5.13% and 3.68%, respectively. The major deficiency of the 10-h FMC model was that it poorly caught the difference in the drying process after rainfall between 10-h FMC and EMC. From the analysis of 10-h FMC during the dates fire occurred, more than 70% of the fires occurred under a 10-h FMC condition of less than 10.5%. Overall, the present study suggested a simple model estimating 10-h FMC with acceptable performance. Applying the 10-h FMC model to the automatic mountain weather observation system was successfully tested to produce a national-scale 10-h FMC spatial distribution map. This data will be fundamental information for forest fire research, and will support the policy maker.

• The korean journal of orthodontics
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• v.36 no.5
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• pp.339-348
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• 2006

Objective: With development of the skeletal anchorage system, orthodontic mini-implant (OMI) assisted on masse sliding retraction has become part of general orthodontic treatment. But compared to the emphasis on successful anchorage preparation, the control of anterior teeth axis has not been emphasized enough. Methods: A 3-D finite element Base model of maxillary dental arch and a Lingual tipping model with lingually inclined anterior teeth were constructed. To evaluate factors influencing the axis of anterior teeth when OMI was used as anchorage, models were simulated with 2 mm or 5 mm retraction hooks and/or by the addition of 4 mm of compensating curve (CC) on the main archwire. The stress distribution on the roots and a 25000 times enlarged axis graph were evaluated. Results: Intrusive component of retraction force directed postero-superiorly from the 2 mm height hook did not reduce the lingual tipping of anterior teeth. When hook height was increased to 5 mm, lateral incisor showed crown-labial and root-lingual torque and uncontrolled tipping of the canine was increased.4 mm of CC added to the main archwire also induced crown-labial and root-lingual torque of the lateral incisor but uncontrolled tipping of the canine was decreased. Lingual tipping model showed very similar results compared with the Base model. Conclusion: The results of this study showed that height of the hook and compensating curve on the main archwire can influence the axis of anterior teeth. These data can be used as guidelines for clinical application.

• KDI Journal of Economic Policy
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• v.12 no.1
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• pp.31-68
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• 1990

The concentration of economic power takes the form of one or a few firms controlling a substantial portion of the economic resources and means in a certain economic area. At the same time, to the extent that these firms are owned by a few individuals, resource allocation can be manipulated by them rather than by the impersonal market mechanism. This will impair allocative efficiency, run counter to a decentralized market system and hamper the equitable distribution of wealth. Viewed from the historical evolution of Western capitalism in general, the concentration of economic power is a paradox in that it is a product of the free market system itself. The economic principle of natural discrimination works so that a few big firms preempt scarce resources and market opportunities. Prominent historical examples include trusts in America, Konzern in Germany and Zaibatsu in Japan in the early twentieth century. In other words, the concentration of economic power is the outcome as well as the antithesis of free competition. As long as judgment of the economic system at large depends upon the value systems of individuals, therefore, the issue of how to evaluate the concentration of economic power will inevitably be tinged with ideology. We have witnessed several different approaches to this problem such as communism, fascism and revised capitalism, and the last one seems to be the only surviving alternative. The concentration of economic power in Korea can be summarily represented by the "jaebol," namely, the conglomerate business group, the majority of whose member firms are monopolistic or oligopolistic in their respective markets and are owned by particular individuals. The jaebol has many dimensions in its size, but to sketch its magnitude, the share of the jaebol in the manufacturing sector reached 37.3% in shipment and 17.6% in employment as of 1989. The concentration of economic power can be ascribed to a number of causes. In the early stages of economic development, when the market system is immature, entrepreneurship must fill the gap inherent in the market in addition to performing its customary managerial function. Entrepreneurship of this sort is a scarce resource and becomes even more valuable as the target rate of economic growth gets higher. Entrepreneurship can neither be readily obtained in the market nor exhausted despite repeated use. Because of these peculiarities, economic power is bound to be concentrated in the hands of a few entrepreneurs and their business groups. It goes without saying, however, that the issue of whether the full exercise of money-making entrepreneurship is compatible with social mores is a different matter entirely. The rapidity of the concentration of economic power can also be traced to the diversification of business groups. The transplantation of advanced technology oriented toward mass production tends to saturate the small domestic market quite early and allows a firm to expand into new markets by making use of excess capacity and of monopoly profits. One of the reasons why the jaebol issue has become so acute in Korea lies in the nature of the government-business relationship. The Korean government has set economic development as its foremost national goal and, since then, has intervened profoundly in the private sector. Since most strategic industries promoted by the government required a huge capacity in technology, capital and manpower, big firms were favored over smaller firms, and the benefits of industrial policy naturally accrued to large business groups. The concentration of economic power which occured along the way was, therefore, not necessarily a product of the market system. At the same time, the concentration of ownership in business groups has been left largely intact as they have customarily met capital requirements by means of debt. The real advantage enjoyed by large business groups lies in synergy due to multiplant and multiproduct production. Even these effects, however, cannot always be considered socially optimal, as they offer disadvantages to other independent firms-for example, by foreclosing their markets. Moreover their fictitious or artificial advantages only aggravate the popular perception that most business groups have accumulated their wealth at the expense of the general public and under the behest of the government. Since Korea stands now at the threshold of establishing a full-fledged market economy along with political democracy, the phenomenon called the concentration of economic power must be correctly understood and the roles of business groups must be accordingly redefined. In doing so, we would do better to take a closer look at Japan which has experienced a demise of family-controlled Zaibatsu and a success with business groups(Kigyoshudan) whose ownership is dispersed among many firms and ultimately among the general public. The Japanese case cannot be an ideal model, but at least it gives us a good point of departure in that the issue of ownership is at the heart of the matter. In setting the basic direction of public policy aimed at controlling the concentration of economic power, one must harmonize efficiency and equity. Firm size in itself is not a problem, if it is dictated by efficiency considerations and if the firm behaves competitively in the market. As long as entrepreneurship is required for continuous economic growth and there is a discrepancy in entrepreneurial capacity among individuals, a concentration of economic power is bound to take place to some degree. Hence, the most effective way of reducing the inefficiency of business groups may be to impose competitive pressure on their activities. Concurrently, unless the concentration of ownership in business groups is scaled down, the seed of social discontent will still remain. Nevertheless, the dispersion of ownership requires a number of preconditions and, consequently, we must make consistent, long-term efforts on many fronts. We can suggest a long list of policy measures specifically designed to control the concentration of economic power. Whatever the policy may be, however, its intended effects will not be fully realized unless business groups abide by the moral code expected of socially responsible entrepreneurs. This is especially true, since the root of the problem of the excessive concentration of economic power lies outside the issue of efficiency, in problems concerning distribution, equity, and social justice.

• Progress in Medical Physics
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• v.22 no.4
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• pp.190-197
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• 2011

Currently, the dose distribution calculation used by commercial treatment planning systems (TPSs) for high-dose rate (HDR) brachytherapy is derived from point and line source approximation method recommended by AAPM Task Group 43 (TG-43). However, the study of Monte Carlo (MC) simulation is required in order to assess the accuracy of dose calculation around three-dimensional Ir-192 source. In this study, geometry factor was calculated using segmented sources integration method by dividing microSelectron HDR Ir-192 source into smaller parts. The Monte Carlo code (MCNPX 2.5.0) was used to calculate the dose rate $\dot{D}(r,\theta)$ at a point ($r,\theta$) away from a HDR Ir-192 source in spherical water phantom with 30 cm diameter. Finally, anisotropy function and radial dose function were calculated from obtained results. The obtained geometry factor was compared with that calculated from line source approximation. Similarly, obtained anisotropy function and radial dose function were compared with those derived from MCPT results by Williamson. The geometry factor calculated from segmented sources integration method and line source approximation was within 0.2% for $r{\geq}0.5$ cm and 1.33% for r=0.1 cm, respectively. The relative-root mean square error (R-RMSE) of anisotropy function obtained by this study and Williamson was 2.33% for r=0.25 cm and within 1% for r>0.5 cm, respectively. The R-RMSE of radial dose function was 0.46% at radial distance from 0.1 to 14.0 cm. The geometry factor acquired from segmented sources integration method and line source approximation was in good agreement for $r{\geq}0.1$ cm. However, application of segmented sources integration method seems to be valid, since this method using three-dimensional Ir-192 source provides more realistic geometry factor. The anisotropy function and radial dose function estimated from MCNPX in this study and MCPT by Williamson are in good agreement within uncertainty of Monte Carlo codes except at radial distance of r=0.25 cm. It is expected that Monte Carlo code used in this study could be applied to other sources utilized for brachytherapy.

• Korean Journal of Environment and Ecology
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• v.34 no.3
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• pp.249-258
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• 2020

This study aims to provide reference material for effective forest management techniques at the catchment scale, based on the field investigation of large woody debris (LWD) in 11 streams within a third-order forest catchment in Gangwon Province, Korea. To achieve this aim, we analyzed the morphological features of LWD pieces, and the storage and distribution status of LWD by stream order throughout the entire investigation. As a result, a total of 1,207 individual pieces of LWD were categorized into three types as follows: (ⅰ) 1,142 pieces (95%) as only trunk and 65 pieces (5%) as a trunk with root wad, (ⅱ) 1,015 pieces (84%) as non-thinned and 192 pieces (16%) as the thinned, and (ⅲ) 1,050 pieces (87%) as conifer and 157 pieces (13%) as broadleaf. Additionally, in-stream LWD loads (㎥/ha) decreased with increasing stream order, yielding 105.4, 71.3, and 35.6 for first-, second-, and third-order streams, respectively. On the other hand, the ratio of LWD jams to the total LWD volume increased with increasing stream order, yielding 11%, 43%, and 49% for first-, second-, and third-order streams, respectively. Finally, a comparison of the in-stream LWD load with previous studies in several countries around the world indicated that in-stream LWD load was positively correlated with forest stand age even though the climate, topography, forest soil type, forest composition, stand growth rate, disturbance regime, and forest management practices were different. These results could contribute to understanding the significance of LWD as a by-product of forest ecosystems and an indicator of riparian forest disturbance. Based on this, we conclude that advanced forest management techniques, including treatment of thinning slash and stand density control of riparian forest by site location (hillslope and riparian zone, or stream order), should be established in the future, taking the forest ecosystem and the aquatic environment from headwater streams to low land rivers into consideration.