• Journal of the Korean Geographical Society
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• 제28권3호
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• pp.247-267
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• 1993

According to developing international economy since the World War II, the increase and competition of the national business is so empha-sized tht both the interest and the necessity about marine transportation playing the impor-thant role of international transportation are increased. Today, the container transportation, as called the innovation of marine transport has been prevailed since the 1970's. The purpose of this paper is to grasp the spatial structure of the hinterlands and forelands, its object is export container cargo at Pusan Export Port, as known for the transportation node of modern containerlization. In this study, for the purpose of grasping the relation between hinterlands and forelands of Korean export container cargo, first, I researched the transition of carloading about container cargo, the bistribution channel of cargo, the change of the items of container and the carlo-adings about transport route, secondly, I used the cluster analysis so as to group hinterlands according to the items of goods and forelands. The object of the analysis is container cargo of Choyang Line, Hanjin Shipping and Hyundai Merchant Marine of National Frag Carriers. The source materials used in this study are Trucking Data of Hanjin Co., Container Ren-tal Data of Samik Transport Co. and Transpor-ting Present Condition Tables of Hyundai Mer-chant Marine. 1. There are two kinds of the transport classi-fied by its form: FCL and LCL. In Pusan Con-tainer Export, a lot of textile goods, clothings and furniture, compound, electric goods, and so on are dealed with but the rate of occupation of the transport is getting lower while that of occupation of equipment, papers and agricultu-ral, mineral and livestock industry higher. 2. In 1990, the transports of container cargo in Korea consist of 7 services and round-the world lines. We can list North America lines, East-South Asian lines, Japan lines and Inter European lines, in order of the quantity of tran-sport form the largest to the smaller. We can have another list that Japan lines, North Ame-rica lines and East-South lines in order of the rate participation of national flag carriers, be-cacuse Korean foreign trade lay disproportionate emphasis on East-South Asian lines. Japan lines among them is the biggest import-export market. Since the rationlization policy of marine tran-sport in 1984, each of national flag carriers have its own lines. Hanjin Shipping predominates over North America lines, Choyang Line over New Zealand, Inter European and Austria lines and Hyundai Merchant Marine over Center-South America lines, in terms of the volume of transport. And small-to-medium sized shippers are prevailing in lines which are adjacent to Korea, Such as Japan lines and East-South Asian lines. 3. In relation to hinterlands and forelands of Choyang Line, the light industry goods, electric goods and machinary produced in Seoul and Pusan are exported to the major ports in Europe and Japan, the same produces in Suwon, Ulsan, Kumi are exported to European Ports, and those in Incheon and Kwangju Austrian and Japanese ports, and those in the rest regions to the major port in Japan. 4. In relation to hinterlands and forelands of Hanjin Shipping, the light industry goods pro-ducing in Seoul and Pusan, the electric goods and machinary in Incheon and Pyeongteck, are exported to New York and Los Angeles. Electric goods and machinary Masan, Anyang, Cheona, Cheongju and Incheon, Electric goods machinary and light industry goods in Kwangju and non mental goods in Pohang, are exported New York, Los Angeles and Oakland. 5. In relation to hinterlands and forelands of Hyundai Merchant Marine, the region of Seoul, Pusan and Incheon closely related with the main ports in U.S.A. The rest regions with Montreal. The hinterlands of export container cargo can be classified by its export items into three kinds: the large city, industrial city and the rest city. Choyang Line's forelands are European lines, Japan lines and Austria lines, and Hanjin Shipping's forelands are North America lines, and Hyundai Merchant Marine's forelands are North America lines and Japan line. 3 National flag carriers' major forelands are determined by the size of port and the shipper's convenient use of the port terminal.

• Journal of Agricultural Extension & Community Development
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• 제21권4호
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• pp.1125-1147
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• 2014

This study was conducted to develop the health evaluation indicator of pond wetland in order to enhance the quality of eco-experience in rural area. The methods for development of evaluation indicator were consisted of 3 stages; 1st, the precedent assessment protocol was applied to 10 pond wetlands in farm villages, and eco-experience expert survey was conducted to selection the evaluation item and criteria at 2nd and 3rd stages. In the results of applying the precedent assessment protocol, we found out two problems; 1) the evaluation result of value determination and conservation value were too simple, and 2) the score by evaluation items were nearly the same, because evaluation criteria in not precisely for application in rural area. These results were reflected to expert survey. According to the 1st survey results, they suggested that 4 items should be maintained, and 3 items should be deleted, and 2 items should be modified among a total of 9 times. Therefore, it was modified into the evaluation protocol having a total of 8 items. According to the 2nd survey results, the selected evaluation items were generally proper. With regard to items for assessing the health condition of pond wetland, we selected a total of 8 items; (1) Connectivity to forest, (2) Connectivity between water body and wetland connection, (3) Number of Vegetation, (4) Surround land use, (5) Interspersion of Vegetation, (6) Crossing Structure, (7) Wetland size, and (8) Outlet structure. In addition, it was suggested that accessibility, visibility, and trash were need for utilization of pond wetland as a place for eco-experience. It is expected that the selected evaluation indicator can help to utilize the pond wetland as an eco-experience space in rural area, and maintain the pond wetland as a space for conservation of biodiversity.

• Korean Journal of Environment and Ecology
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• 제29권5호
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• pp.764-776
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• 2015

This study aims to identify the structure of the plant community, and the ecological succession sere and the change in the forest ecosystem in Jungdaesa-Birobong area, Odaesan National Park_(i._e., located at high altitudes(over 1,000m)). It seeks to offer the basic data for the planning of vegetation management. In order to verify the status of the forest vegetation between Jungdaesa-Birobong, seventeen plots(size is $20m{\times}20m$) were set up as research sites at high altitudes. Importance value, distribution by diameter at breast height(DBH), the growth volume and age of the sample trees, similarity index and species diversity index of each survey plot were analysed. According to the results of DCA(Detrended Correspondence Analysis), one of the multivariate statistical techniques. It was found that the plant communities were classified into five groups: community I_(Quercus mongolica-Tilia amurensis community), community II_(Q. mongolica-Deciduous broad-leaved community), community III_(Q. mongolica-Pinus koraiensis community), community IV_(Abies holophylla-Q. mongolica community) and community V_(A. holophylla-Deciduous broad-leaved community). Community I which is dominated by Quercus mongolica and Deciduous broad-leaved communities is located at an altitude of over 1,300 meters(ranging from 1,335m to 1,495m), the community IV and V which are dominated by Abies holophylla are located at an altitude of under 1,200 meters(ranging from 1,115m to 1,175m) and the community II and III which include the main species of Quercus mongolica, Pinus koraiensis and Abies holophylla are located at an altitude of between 1,160 meters and 1,300 meters. The results showed that Quercus mongolica tends to have a higher importance value of woody species at a higher altitude while Abies holophylla tends to have higher importance value at a lower altitude. For the importance value woody species and -DBH class distribution, the communites I, II and III are expected to continuously maintain the present status. Whereas, for the influence of communities IV and V, Q. mongolica is predicted to be weakened. The age of sample trees was between 85 and 161; the average age was 123. The index of Shannon's Species diversity (H') showed heterogeneity was found among community I_(i._e., located at high altitude) and communities IV and V_(i._e., located at low altitude). As a results of analysing the index of Shannon's Species diversity (H': unit: $400m^2$), community III showed the highest diversity intex with 1.1109 followed by community II with 1.0475, community I with 1.0125, community IV with 0.9918 and community V with 0.8686. This study verified that the index of Shannon's species was significantly different by plant communities. For instance, when comparing the index of Shannon's species diversity in Quercus mongolica communities of this study and that of past relevant research, the value of index is very similar. However, the diversity index for the community which is dominated by Abies holophylla showed lower value when compared to the results from past relevant research.

• Korea journal of population studies
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• 제9권1호
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• pp.41-53
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• 1986

The purpose of this paper is two-fold. One is to investigate the determinants of the demand supply of labor, and another is to project long-term demand and supply of labor. The paper consists of three parts. In the first part, theoretical models and important hypotheses are discussed: for the case of a labor supply model, issues regarding discouraged worker model, permanent wage hypothesis, and relative wage hypothesis are examined and for the case of a demand model, issues regarding estimating an employment demand equation within the framework of an inverted short-run produc- tion function are inspected. Particularly, a theoretical justification for introducing a demographic cohort variable in a labor supply equation is also investigated. In the second part, empirical results of the estimated supply and demand equations are analyzed. Supply equations are specified differently between primary and secondary labor force. That is, for the case of primary labor force groups including males aged 25 and over, attempts are made to explain the variations in participation behavior within the framework of a neo-classical economics oriented permanent wage hypothesis. On the other hand, for the case of females and young male labor force, variations in participation rates are explained in terms of a relative wage hypothesis. In other words, the participation behavior of primary labor force is related to short-rum business fluctuations, while that of secondary labor force is associated with intermediate swings of business cycles and demographic changes in the age structure of population. Some major findings arc summarized as follows. (1) For the case of males aged 14~19 and 2O~24 groups and females aged 14∼19, the effect of schhool enrollment rate is dominant and thus it plays a key role in explaining the recent declining trend of participation rates of these groups. (2) Except for females aged 20∼24, a demographic cohort variable, which captures the impact of changes in the age structure on participation behavior, turns out to show positive and significant coefficients for secondary labor force groups. (3) A cyclical variable produce significant coefficients for prime-age males and females reflecting that as compared to other groups the labor supply behavior of these groups is more closely related to short-run cyclical variations (4) The wage variable, which represents a labor-leisure trade-off turns out to yield significant coefficients only for older age groups (6O and over) for both males and females. This result reveals that unlike the experiences of other higer-income nations, the participation decision of the labor force of our nation is not highly sensitive with respect to wage changes. (5)The estimated result of the employment demand equation displays that given that the level of GNP remains constant the ability of the economy to absord labor force has been declining;that is, the elasticity of GNP with respect to labor absorption decreasre over time. In the third part, the results of long-term projections (for the period of 1986 and 1995) for age-sex specific participation rates are discussed. The participation rate of total males is anticipated to increase slightly, which is contrary to the recent trend of declining participation rates of this group. For the groups aged 25 and below, the participation rates are forecast to decline although the magnitude of decrease is likely to shrink. On the other hand, the participation rate of prime- age males (25 to 59 years old) is predicted to increase slightly during 1985 and 1990. For the case of females, except for 20∼24 and 25∼34 age groups, the participation rates are projected to decrease: the participation rates of 25∼34 age group is likely to remain at its current level, while the participation rate of 20∼24 age group is expected to increase considerably in the future (specifi- cally, from 55% in 1985 to 61% in 1990 and to 69% in 1995). In conclusion, while the number of an excess supply of labor will increase in absolute magnitude, its size as a ratio of total labor force is not likely to increase. However, the age composition of labor force is predicted to change; that is, the proportion of prime-age male and female labor force is projected to increase.

• Economic and Environmental Geology
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• 제53권1호
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• pp.33-43
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• 2020

CO₂ geological storage is currently considered as the most stable and effective technology for greenhouse gas reduction. The saline formations for CO₂ geological storage are generally located at a depth of more than 800 m where CO₂ can be stored in a supercritical state, and an extensive impermeable cap rock that prevents CO₂ leakage to the surface should be distributed above the saline formations. Trough analysis of seismic and well data, we identified the basalt flow structure for potential CO₂ storage where saline formation is overlain by basalt cap rock around PZ-1 exploration well in the Southern Continental Shelf of Korea. To evaluate CO₂ storage capacity of the saline formation, total porosity and CO₂ density are calculated based on well logging data of PZ-1 well. We constructed a 3D geological grid model with a certain size in the x, y and z axis directions for volume estimates of the saline formation, and performed a property modeling to assign total porosity to the geological grid. The estimated average CO₂ geological storage capacity evaluated by the U.S. DOE method for the saline formation covered by the basalt cap rock is 84.17 Mt of CO₂(ranges from 42.07 to 143.79 Mt of CO₂).

• Tunnel and Underground Space
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• 제30권4호
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• pp.320-334
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• 2020

This study presents an application of hydro-mechanical coupled Particle Flow Code 3D (PFC3D) to simulation of fluid injection induced fault slip experiment conducted in Mont Terri Switzerland as a part of a task in an international research project DECOVALEX-2019. We also aimed as identifying the current limitations of the modelling method and issues for further development. A fluid flow algorithm was developed and implemented in a 3D pore-pipe network model in a 3D bonded particle assembly using PFC3D v5, and was applied to Mont Terri Step 2 minor fault activation experiment. The simulated results showed that the injected fluid migrates through the permeable fault zone and induces fault deformation, demonstrating a full hydro-mechanical coupled behavior. The simulated results were, however, partially matching with the field measurement. The simulated pressure build-up at the monitoring location showed linear and progressive increase, whereas the field measurement showed an abrupt increase associated with the fault slip We conclude that such difference between the modelling and the field test is due to the structure of the fault in the model which was represented as a combination of damage zone and core fractures. The modelled fault is likely larger in size than the real fault in Mont Terri site. Therefore, the modelled fault allows several path ways of fluid flow from the injection location to the pressure monitoring location, leading to smooth pressure build-up at the monitoring location while the injection pressure increases, and an early start of pressure decay even before the injection pressure reaches the maximum. We also conclude that the clay filling in the real fault could have acted as a fluid barrier which may have resulted in formation of fluid over-pressurization locally in the fault. Unlike the pressure result, the simulated fault deformations were matching with the field measurements. A better way of modelling a heterogeneous clay-filled fault structure with a narrow zone should be studied further to improve the applicability of the modelling method to fluid injection induced fault activation.

• Korean Journal of Materials Research
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• 제5권8호
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• pp.988-996
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• 1995

CuInSe$_2$this films as a light absorber layer were fabricated by vacuum evaporation using In$_2$Se$_3$and Cu$_2$Se precursors and their properties were analyzed. Indium selenide films of 0.5${\mu}{\textrm}{m}$ thickness were first deposited by vacuum evaporation of In$_2$Se$_3$ on a Corning 7059 glass substrate. The films deposited at suscepor temperature of 40$0^{\circ}C$ showed a flat surface morphology with densely Packed grain structure. CuInSe$_2$films directly formed by evaporating Cu$_2$Se on the predeposited In$_2$Se$_2$films also showed a very flat surface when the susceptor temperature was $700^{\circ}C$. Cu$_2$Se, a second phase in the CuInSe$_2$film, was removed by evaporating additional In$_2$Se$_3$on the CuInSe$_2$film at $700^{\circ}C$. The grain size of 1.2${\mu}{\textrm}{m}$ thick CuInSe$_2$, film was about 2${\mu}{\textrm}{m}$ and the film had a (112) preferred orientation. As the amount of deposited In$_2$Se$_3$increased, the electrical resistivity of CuInSe$_2$films increased because of the decrease of hole concentration. But the optical band gap was almost constant at the value of 1.04eV, The CuInSe$_2$film grown on a Mo/glass substrate had a similar smooth microstructure compared to that on a glass substrate. A solar cell with ZnO/CdS/CuInSe$_2$/Mo structure may be realized based on the above CuInSe$_2$films.

• Journal of the Korean Society of Marine Environment & Safety
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• 제16권2호
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• pp.175-183
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• 2010

To understand the variation of macro benthos community according to the installation of structure and topographic placement in the shellfish farm on tidal flat, the practical example of the tidal shellfish growing area at Namsung-ri Goheung was observed. The results of the research for the field observation were summarized as follows. (1) The ground gradient of the shellfish farm was very flat below about $1^{\circ}$. The shellfish farm ground took the shape of $\sqcup$ from the shoreline to the place of 150 m seawards, and the shape of $\sqcap$ from there to the low tide line. During ebb tide, the $\sqcup$ shape ground stored the sea water, and the $\sqcap$ shape ground was supposed to act as the effect factor to leak slowly or to prevent the outflow. (2) The oyster shell bag or the type of riprap wall as the boundary in the shellfish farm was classified into five types. The air exposure time and flooding time were 181 and 434 minutes, respectively. (3) In the numerical experiment, the deep-sea water wave coming in the study area had 0.5 m of maximum wave height to show the very stable conditions and the wave direction pattern of S-direction was dominant at Naro great ridge, and SE, SSW and S-direction were distributed strongly around the shellfish farm. (4) By the grain size analysis, the sediment around tidal flat consisted of gravel 0.00~5.81(average 1.70)%, sand 14.15~18.39(average 13.23)%, silt 27.59~47.15(average 30.84)% and clay 35.79~55.73(average 36.19)%, and the sediment type was divided into (g)M(lightly gravelly mud), sM(sandy mud) and gM(gravelly mud) by Folk's diagram. (5) The macro benthos community survey conducted in this site in January, 2010 showed that 1 species of Mollusca, 8 species of Polychaeta and 2 species of Crustacea appeared, and 11 species occupying over 1% of total abundance were dominant.

• Korean Journal of Fisheries and Aquatic Sciences
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• 제33권4호
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• pp.307-319
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• 2000

Community structure (seasonal fluctuation), taxon diversity, nematodes/benthic harpacticoids and nematodes/kinorhynchs ratios of meiobenthos were studied in the Gamak Bay, Korea. A series of samplings were carried out from April 1997 to May 1999. Meiobenthic organisms was collected by van Veen grab and three subcores of 34 mm in internal diameter were taken from each sediment sample. The total density of meiobenthos in each seasons was found to be the highest in May 1999, and the lowest in December 1998. Total density of meiobenthos at each station was the highest at Station 9 in May 1999 ($2,218 inds./10 cm^2$) and the lowest at Station 3 in December 1998 ($2 inds./10 cm^2$). The Gamak Bay seemed to have an individual number increased from the inner toward the outer stations. The highest number of meiobenthos was observed on 0.125 and 0.063 mm mesh size. In every season, over $80{\%}$ of the meiobenthos was composed of only four groups: nematodes, benthic harpacticoids, sarcomastigophorans and nauplius larvae of crustaceans. Seasonal fluctuation of meiobenthos was also studied. The nematodes/benthic harpacticoids(nematodes/kinorhynchs) ratios were studied as an index of pollution monitoring for benthic ecosystem at each station in each season. The value of nematodes/benthic harpacticoids ratio was the highest at the inner stations and the lowest at the outer stations in the Gamak Bay. Taxon diversity (H') was the highest at the outer stations and the lowest at the inner stations in the Gamak Bay. The value of nematodes/benthic harpacticoids ratio significantly increased from the outer toward the inner stations, whereas the taxon diversity (H') significantly increased from the inner toward the outer stations in Gamak Bay.

• Journal of Plant Biology
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• 제3권1호
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• pp.16-25
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• 1960

HARN, Chang Yawl (Chonnam U. Kwangju, Korea): Siudies on the dimorpism of the Perisicaria senticosa Nakai-Kor. jour. Bot. 3(1) 16-25 During his researches regarding the morphological and physiological properties of Polygonecenae, the author has found that the species, Persicaria senticosa, aiso, besides the heterostylous plants of Polygonum family, Fagopyrum esculentum, and Persicaria japonica which was recently verified by the author as dimorphic, shows the typical floral structure of heterostylism, the description of which is not found in taxonomical works. Further research on this species have revealed that this plant, despite pressessing characteristic structural dimorphism, does not exhibit even the slight signs of heterostlylous properties physiologically. This is a deviation from the usual behavior of normal heterostylous plants. What is interesting is the fact that the physiological behavior of this species is quite contrary to that of P. japonica which is considered to be the most highly specialized dimorphic plant. Thus it is assurred that if some species of this family had taken a heterostylic form in its course of development from autogamy to allogamy, P. seoticosa would be the least differentiated type of dimorphic forms among the three heterostylous plants, including buckwheat, of this family. The results obtained in this experiment are summarized as follows: 1) P. senticosa has two forms of flower, one, long style-short stamened; the other, short style-long stamened. Not only conspicuous is this primary difference, but the secondary difference, such as pollen grain size, is noticeable between long and short styled individuals, thus expressing structurally the definite trait of a dimorphic plant. 2) Structural alteration of floral parts towards dimorphism has preceeded far less in comparison with those of the P. japonica and F. esculentum. 3) Elaborate studies on fertility reveal that this species does not show the slightest sign of the physiological characteristics of dimorphic plants. In other words, regardless of the modes of combinations, legitimate and illegitimate, fertilization and fruit setting flourish unimpaired. 4) Growth of pollen tubes apparently parallels the results in the fertility, tubes reaching ovary approximately 30 minutes after pollination both in legitimate and illegitimate combinations. Pollen tube penetration appears to be comparatively rapid. 5) A slight difference in the growth of pollen tube seems to exist between legitimate and illegitimate combinations, legitimate union giving slightly faster tube penetration. 6) In the present experiment it was clarified that P. senticosa, known to possess one form of flower in taxonomy, is in reality dimorphic plant having two of flowers. Although this species is definitely heterostylous in floral structure, physiological evidence and pollen tube behavior show that the differentiation of this plant toward the dimorphism has apparently proceeded slightly except for some parts of floral organ. In ordinary heterostylous plants it is a matter of common occurrence that when illegitimately cmbined, there is poor or no fertility, Contrary to the universal property of heterostylous plants, no difference is observed in the fertility and pollen tube growth between the legitimate and illegitimate combinations in the case of P. senticosa. Compared to the P. japonica and F. esculentum, which are supposed to have undergone high degree of dimorphic differentiation, it is an unavoidable conclusion that P. senticosa has not yet developed as a heterostyle plant except for some of its floral parts. If P. japonica is assumed to be the most differentiated type of hetenostylous plant, thenthe P. senticosa would be regarded as the primitive, retaining still the self-fertile nature so common to the Polygonum genus. In nature, however, this plant has a better chance to be pollinated legitimately owing to the two forms of flowers than to be pollinated illegitimately. The author is indebted to Dong Chul, Kim as well as other members of the Department of Plant Breeding and Genetics of Chonnam National University for their efforts out the laborious experiments during the course of the present studies.