• The Journal of the Petrological Society of Korea
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• v.28 no.4
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• pp.251-277
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• 2019

The Gogunsan Archipelago is composed of two island groups; the first group includes Mal-do, Myeong-do, Gwangdae-do, and Bangchuk-do islands consisting of Neoproterozoic rocks, and the second group includes Yami-do, Sinsi-do, Muneo-do, Jangja-do, and Seonyu-do islands consisting of Cretaceous rocks. The first group mainly consists of the Bangchuk formation which can be divided into two layers; the lower layer was more deformed than the upper layer. The former was intruded by mafic and felsic volcanic rocks formed in the volcanic arc tectonic setting 930-890 Ma and the latter was deposited ca. 825-800 Ma. In these islands, large scale folds with east-west fold axes were beautifully formed; the Maldo island fold was designated as natural monument and large scale beautiful chevron fold was developed on the Gwangdae-do island. In addition, there are unique zebra-shaped outcrop formed by a mixing of basic and acidic magma and Independent Gate shaped outcrop formed by coastal erosion. On the other hand, the Yami-do, Sinsi-do, Muneo-do, Jangja-do and Seonyu-do islands consist of 92-91Ma Cretaceous volcanic rocks and, in Sinsi-do island, the Nanshan formation deposited ca. 92 Ma. These Cretaceous volcanic rocks formed by melting of the continental crust by the heat supplied from the uplifting mantle due to the extension caused by a retreat of subducting ocean slab. Yami-do and Sinsi-do islands are composed of rhyolite. In Yami-do island, bands with vertical joint formed by cooling of the bottom part of the lava, are shown. In Sinsi-do island, large-scale vertical joints formed by cooling of lava flow, were developed. The Jangja-bong of Jangja-do island and Mangju-bong of Seonyu-do island are composed of brecciated rhyolite and formed a ring shaped archipelago contributing to the development of marine culture by providing natural harbor condition. They also provide beautiful views including 'Seonyu 8 views' along with other islands. As mentioned above, the Gogunsan archipelago is rich in geoheritages and associated cultural and historical resources, making it worth as a National Geopark.

• Korean Journal of Ecology and Environment
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• v.47 no.1
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• pp.13-23
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• 2014

To obtain optimum filter media, configuration method and greenhouse wastewater loading in small-scale constructed wetlands (CWs) for treating greenhouse wastewater, the apparatuses were constructed with 4 kinds of combined systems such as vertical flow (VH)-Horizontal flow (HF), HF-VH, HF-VF-HF, VF-HF-HF CWs. The efficiencies of pollutants in greenhouse wastewater were investigated in various CWs under different filter media, configuration methods and agricultural water loading. Removal rates of pollutants under different filter media were in the other of coarse sand>broken stone${\fallingdotseq}$calcite${\fallingdotseq}$mixed filter media for COD, broken stone>mixed filter media>coarse sand>calcite for T-N, and calcite>mixed filter media>broken stone>coarse sand for T-P. The removal rates of pollutants in HF-VH-HF CWs at different configuration methods were higher than those in other configuration methods. The removal rates of pollutants were higher in the order of $150L\;m^{-2}day^{-1}{\fallingdotseq}300L\;m^{-2}day^{-1}$ > $600L\;m^{-2}day^{-1}$ under different greenhouse wastewater loading. Therefore, optimum configuration method was HF-VH-HF CWs, the optimum filter media was mixed filter media (coarse sand : broken stone : calcite=1 : 1 : 1), and the optimum greenhouse wastewater loading was $300L\;m^{-2}day^{-1}$ in HF-VH-HF CWs.

• Journal of Distribution Science
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• v.10 no.2
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• pp.29-41
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• 2012

This paper undertakes a conceptual review of transaction cost to broaden the understanding of the transaction cost analysis (TCA) approach. More than 40 years have passed since Coase's fundamental insight that transaction, coordination, and contracting costs must be considered explicitly in explaining the extent of vertical integration. Coase (1937) forced economists to identify previously neglected constraints on the trading process to foster efficient intrafirm, rather than interfirm, transactions. The transaction cost approach to economic organization study regards transactions as the basic units of analysis and holds that understanding transaction cost economy is central to organizational study. The approach applies to determining efficient boundaries, as between firms and markets, and to internal transaction organization, including employment relations design. TCA, developed principally by Oliver Williamson (1975,1979,1981a) blends institutional economics, organizational theory, and contract law. Further progress in transaction costs research awaits the identification of critical dimensions in which transaction costs differ and an examination of the economizing properties of alternative institutional modes for organizing transactions. The crucial investment distinction is: To what degree are transaction-specific (non-marketable) expenses incurred? Unspecialized items pose few hazards, since buyers can turn toalternative sources, and suppliers can sell output intended for one order to other buyers. Non-marketability problems arise when specific parties' identities have important cost-bearing consequences. Transactions of this kind are labeled idiosyncratic. The summarized results of the review are as follows. First, firms' distribution decisions often prompt examination of the make-or-buy question: Should a marketing activity be performed within the organization by company employees or contracted to an external agent? Second, manufacturers introducing an industrial product to a foreign market face a difficult decision. Should the product be marketed primarily by captive agents (the company sales force and distribution division) or independent intermediaries (outside sales agents and distribution)? Third, the authors develop a theoretical extension to the basic transaction cost model by combining insights from various theories with the TCA approach. Fourth, other such extensions are likely required for the general model to be applied to different channel situations. It is naive to assume the basic model appliesacross markedly different channel contexts without modifications and extensions. Although this study contributes to scholastic research, it is limited by several factors. First, the theoretical perspective of TCA has attracted considerable recent interest in the area of marketing channels. The analysis aims to match the properties of efficient governance structures with the attributes of the transaction. Second, empirical evidence about TCA's basic propositions is sketchy. Apart from Anderson's (1985) study of the vertical integration of the selling function and John's (1984) study of opportunism by franchised dealers, virtually no marketing studies involving the constructs implicated in the analysis have been reported. We hope, therefore, that further research will clarify distinctions between the different aspects of specific assets. Another important line of future research is the integration of efficiency-oriented TCA with organizational approaches that emphasize specific assets' conceptual definition and industry structure. Finally, research of transaction costs, uncertainty, opportunism, and switching costs is critical to future study.

• Korean Journal of Environmental Agriculture
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• v.27 no.3
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• pp.217-224
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• 2008

To obtain optimum configuration, depth and load of constructed wetlands(CWs) for treating of hydroponic waste solution(HWS) which was produced in greenhouses, the study was conducted with 4 kinds of combined systems such as Vertical flow(VF)-Horizontal flow(HF), VF-VF, HF-VF and HF-HF CWs. In four configurations of CWs, the treatment efficiency of pollutants from HWS under depth of HF and VF beds, HWS loading and HWSs were investigated. Removal rate of pollutants under different depth of VF and HF in 2-stage hybrid CWs was in the order of 50 cm < 70 cm regardless of CWs configuration. Removal rate of pollutants under HWS loading in 2-stage hybrid CWs was in the order of $150L\;m^{-2}\;day^{-1}{\fallingdotseq}300L\;m^{-2}\;day^{-1}\;>\;450L\;m^{-2}\;day^{-1}$. The optimum depth and HWS loading were 70 cm and $300L\;m^{-2}\;day^{-1}$ in four configurations of CWs, respectively. Using this optimum condition, for various HWSs (cucumber, paprika and strawberry HWS), removal rate of pollutants in HF-HF CWs was higher than that in HF-VF CWs. Optimum configuration of 2-stage hybrid CWs for treating hydroponic waste solution in greenhouses was found out to be HF-HF CWs. Therefore, under the optimum conditions, removal rate of BOD, COD, SS, T-N and T-P in HF-HF CWs were 84, 81, 84, 51 and 93%, respectively.

• The korean journal of orthodontics
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• v.31 no.4 s.87
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• pp.425-438
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• 2001

The delivery of optimal orthodontic treatment is greatly influenced by clinician's ability to predict and control tooth movement by applying well-known force system to dentition. It is very important to determine the location of the centers of resistance of a tooth or teeth in order to have better understanding the nature of displacement characteristics under various force levels. In this study, three dimensional finite element analysis was used to measure the initial displacement of the consolidated teeth under loading. The purpose of this study was to define the location of the centers of resistance at the upper six anterior segment. To observe the changes of six anterior segment, 200gm, 250gm, 300gm, and 350gm forces at right and left hand side each were imposed toward lingual direction. For this study, two cases, six anterior teeth and six anterior teeth after corticotomy, were reviewed. In addition, it was reviewed the effects of changes on the location of the center of resistance in both cases based on different degree of forces aforementioned. The results were that : 1. The instantaneous center of resistance for the six anterior teeth was vertically located between level 4 and level 5, which is, at 6.76mm, $44.32\%$ apical to the cementoenamel junction level. 2. The instantaneous center of resistance for the six anterior teeth after corticotomy was located vertically between level 4 and level 5, that is, at 7.09mm $46.38\%$ apical to the cementoenamel junction level. 3. Changes of force showed little effect on the location of the center of resistance in each case. 4. It was observed that the location of the instantaneous center of resistance for the six anterior teeth after corticotomy was changed more than the six anterior teeth without corticotomy to the apical part, and the displacement of the consolidated anterior teeth moved further in case of the consolidated teeth after corticotomy.

• Journal of Gastric Cancer
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• v.5 no.4 s.20
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• pp.288-294
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• 2005

Purpose: Superficially spreading (SS) early gastric cancer (EGC) is characterized by wide horizontal extension without deep vertical invasion. It is a relatively rare form of EGC, and it's clinicopathological (C-P) characteristics are not evident. This study aimed to clarify their C-P characteristics. Materials and Methods: We defined SS EGC as invading less than the submucosal layer that measured more than 60 mm in diameter or wider than $5{\times}5cm \;(25cm^2)$ in width. The C-P characteristics and prognosis were compared between 69 patients with SS EGC and 319 patients with the common type EGC (EGC except SS type). Results: For SS EGC lymph node metastases, Lauren's diffuse type, lymphatic invasion were significantly higher than in common type EGC. In patients with SS EGC, all of the metastatic lymph nodes were anatomically distributed within the paragastric region, with fewer along the left gastric artery and common hepatic artery. In 6 cases of SS EGC with resection marqins less than 10 mm, there was no death during the follow-up period (4 to 13 years after operation) if margins were not involved. Age (>58 yrs), tumor site (upper 1/3), lymph node metastasis, submucosal invasion were statistically significant poor prognostic factor in univariate survival analysis. In multivariate survival analysis, age and lymph node metastasis were independent prognostic factors. However, tumor diameter or width was not a significant prognostic factor. Conclusion: Although SS EGC has histologically distinct properties, gastrectomy with free surgical margins and appropriate lymph node dissection $(D1+{\beta})$ could be a suitable treatment.

• Korean Journal of Environmental Biology
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• v.37 no.1
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• pp.93-108
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• 2019

To investigate the temporal-spatial distribution of picophytoplankton in relation to different water masses in the northern East China Sea (ECS), picophytoplankton abundance were investigated using flow cytometry with environmental factors in 2016-2017. The results from the analysis of flow cytometer data showed that Synechococcus appeared across all seasons, exhibiting its minimum abundance in winter and maximum abundance in summer. Furthermore, high abundance was detected in the surface mixed layer during spring and summer when vertical stratification occurs; in particular, Synechococcus exhibited maximum abundance in thermocline layer, indicating a close correlation to water temperature and thermocline formation. In addition, the abundance of Synechococcus indicated a decrease in the western seas in 2017 compared to 2016 under the strong influence of the Changjiang Diluted Water (CDW). This was determined by the significant influence of the CDW on the abundance of Synechococcus during summer in the northern waters of the ECS. In contrast, Prochlorococcus did not appear during winter and spring, and its distribution was limited during summer and autumn in the eastern seas under the influence of the Kuroshio current. The largest range of Prochlorococcus distribution was confirmed during autumn without the influence of the CDW. Thus, the distribution pattern of each picophytoplankton genus was found to be changing in accordance to the extension and reduction of sea current in different seasons and periods of time. This is anticipated to be a useful biological marker in understanding the distribution of sea currents and their influence in the northern waters of the ECS.

• Korean Journal of Heritage: History & Science
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• v.54 no.2
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• pp.38-55
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• 2021

Cherwon Castle is located in Pungcheonwon, Cherwon, in the center of the Korean Peninsula. Currently, it is split across the Demilitarized Zone (DMZ) between the two Koreas. It attracts attention as a symbol of inter-Korean reconciliation and as cultural heritage that serves as data in making important policy decisions on the DMZ. Despite its importance, however, there has not been sufficient investigation and research done on Cherwon Castle. This is due to the difficulty involved in investigation and research and is caused by the site's inaccessibility. As a solution, the current investigative methods in satellite and aerial archeology can be applied to interpret and analyze the structure of Cherwon Castle and the features of its inner space zoning. Cherwon Castle was built on the five flat hills that begin in the northern mountainous hills and stretch to the southwest. The inner and outer walls were built mainly on the hilly ridges, and the palace wall was built surrounding a flat site that was created on the middle hill. For each wall, the sites of the old gates, which were erected in various directions , have been identified. They seem to have been built to fit the direction of buildings in the castle and the features of the terrain. The castle was built in a diamond shape. The old sites of the palace and related buildings and landforms related to water drainage were identified. It was verified that the roads and the gates were built to run from east to west in the palace. In the spaces of the palace and the inner castle, flat sites were created to fit different landforms, and building sites were arranged there. Moreover, the contour of a reservoir that is believed to be the old site of a pond has been found; it lies on the vertical extension of the center line that connects the palace and the inner castle. Between the inner castle and the outer castle, few vestiges of old buildings were found, although many flat sites were discovered. Structurally, Cherwon Castle is rotated about nine degrees to the northeast, forming a planar rectangle. The planar structure derives from the castle design that mimics the hilly landform, and the bending of the southwestern wall also attests to the intention of the architects to avoid the wetland. For now, it is impossible to clearly describe the functions and characters of the building sites inside the castle. However, it is believed that the inner castle was marked out for space for the palace and government offices, while the space between the outer and inner castle was reserved as the living space for ordinary people. The presence of the hilly landform diminishes the possibility that a bangri (grid) zoning system existed. For some of the landforms, orderly zoning cannot be ruled out, as flat areas are commonly seen. As surveys have yet to be conducted on the different castles, the time when the walls were built and how they were constructed cannot be known. Still, the claim to that the castle construction and the structuring of inner spaces were inspired by the surrounding landforms is quite compelling.