• Computational Structural Engineering
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• v.10 no.1
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• pp.135-148
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• 1997

The main objective of this paper is to analyze the rectangular stiffened plates with two opposite ends elastically restrained and the others simply supported subjected to in-plane bending by Finite Element Method. Another objective is to develope Classical Method analyzing the unstiffened rectangular plates with the above boundary conditions. In order to validate finite element and classical methods, the buckling strengths of the rectangular plates with four simply supported ends, and with two simply supported and the others fixed ends by finite element method and classical method are compared with those of references. In finite element method, elastically restrained ends can be obtained as considering torsional and warping rigidities of end stiffeners. The buckling strengths of the rectangular plates with elastically restrained ends by finite element and classical methods are calculated and compared with each other. In case of stiffened plates, to validate finite element method, the buckling strengths of the rectangular stiffened plates with four simply supported ends, and with two simply supported and the others fixed ends are also compared with those of references. The buckling strengths of the rectangular stiffened plates with elastically restrained ends by finite element method are calculated as solving eigenvalue problems which are obtained as assembling rectangular plate elements and beam elements considered torsional and warping rigidities. The buckling strengths of rectangular stiffened plates according to various positions of rectangular intermediate stiffener, J and I/sub w/ of end stiffeners are also obtained, which are compared to determine the efficient position of intermediate stiffener.

• Journal of Environmental Science International
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• v.19 no.5
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• pp.591-605
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• 2010

This study were to simulate major criteria air pollutants and estimate regional source-receptor relationship using air quality prediction model (TAPM ; The Air Pollution Model) in the Seoul Metropolitan area. Source-receptor relationship was estimated by contribution of each region to other regions and region itself through dividing the Seoul metropolitan area into five regions. According to administrative boundary, region I and region II were Seoul and Incheon in order. Gyeonggi was divided into three regions by directions like southern(region III), northern(IV) and eastern(V) area. Gridded emissions ($1km{\times}1km$) by Clean Air Pollicy Support System (CAPSS) of National Institute of Environmental Research (NIER) was prepared for TAPM simulation. The operational weather prediction system, Regional Data Assimilation and Prediction System (RDAPS) operated by the Korean Meteorology Administration (KMA) was used for the regional weather forecasting with 30km grid resolution. Modeling period was 5 continuous days for each season with non-precipitation. The results showed that region I was the most air-polluted area and it was 3~4 times more polluted region than other regions for $NO_2$, $SO_2$ and PM10. Contributions of $SO_2$ $NO_2$ and PM10 to region I, II and III were more than 50 percent for their own sources. However region IV and V were mostly affected by sources of region I, II and III. When emissions of all regions were assumed to reduce 10 and 20 percent separately, air pollution of each region was reduced linearly and the contributions of reduction scenario were similar to those of base case. As input emissions were reduced according to different ratio - region I 40 percent, region II and III 20 percent, region IV and V 10 percent, air pollutions of region I and III were decreased remarkably. The contributions to region I, II, III were also reduced for their own sources. However, region I, II and III affected more regions IV and V. Shortly, graded reduction of emission could be more effective to control air pollution in emission imbalanced area.

• Journal of Korean Society of Forest Science
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• v.106 no.1
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• pp.100-109
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• 2017

This study was conducted for preliminary survey and management support for Pine Wood Nematode (PWN) suppression. We took areal photographs of 6 areas for a total of 2,284 ha during 2 weeks period from 15/02/2016, and produced 6 ortho-images with a high resolution of 12 cm GSD (Ground Sample Distance). Initially we classified 423 trees suspected for PWN infection based on the ortho-images. However, low accuracy was observed due to the problems of seasonal characteristics of aerial photographing and variation of forest stands. Therefore, we narrowed down 231 trees out of the 423 trees based on the initial classification, snap photos, and flight information; produced thematic maps; conducted field survey using GNSS; and detected 23 trees for PWN infection that was confirmed by ground sampling and laboratory analysis. The infected trees consisted of 14 broad-leaf trees, 5 pine trees (2 Pinus rigida), and 4 other conifers, showing PWN infection occurred regardless of tree species. It took 6 days for 2.3 men from to start taking areal photos using UAV (Unmanned Aerial Vehicle) to finish detecting PNW (Pine Wood Nematode) infected tress for over 2,200 ha, indicating relatively high efficacy.

• Analytical Science and Technology
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• v.10 no.1
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• pp.66-74
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• 1997

Influence of the axial dispersion on immobilized enzyme catalytic bed was investigated in order to examine the kinetic behavior of the biocatalysis. The enzyme employed in this study was the tyrosinase(EC 1.14.18.1) immobilized on carbon support : this system requires two substrates of phenol and oxygen. This enzyme has potential application for phenol degradation in waste water. A simulated reactor was a packed-bed reactor of 2.54cm in diameter and 10cm long, loaded with the immobilized carbon particle with an average diameter of $550{\mu}m$. A phenol feed in the strength of 55.5mM(5220ppm) was used to observe the behavior of the immobilized enzyme column at three different dissolved oxygen levels of 0.08445mM(2.7ppm), 0.1689mM(5.4ppm) and 0.3378mM(9.5ppm) with the flow rates in the range of 60(1mL/s) to 180mL/min(3mL/s). Examination of the Biot number and Damkolher numbers of the immobilized system enables us to eliminate the contribution of external mass transfer to set of differential equations derived from the dispersion model. Solution of the equation was finally obtained numerically with the application of the Danckwert boundary conditions and the assumed zero-and first order rates on the non-linear two substrate enzyme kinetics. Higher conversion of phenol was observed at the low flow rates and at the higher oxygen concentration. Comparison of axial dispersion and plug flow model showed that no detectable difference was observed in the column outlet conversion between the axial and the plug flow models which was in complete agreement with the previous studies.

• The Journal of the Korea Contents Association
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• v.21 no.1
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• pp.173-184
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• 2021

This paper aims to examine the effects of perceived social fairness and upward social mobility on the individual emotional depression. Specifically, this study investigates the conditions under which the effects are more or less pronounced for the sake of shedding more light on the relationship between social-cognitive and psychological factors. The key proposition of this study is that as one holds more favorable beliefs about the fairness of the society to which (s)he belong, (s)he would have more optimistic expectations for the possibility of his or her own upward social mobility. Moreover, the decrease of this expectation could exacerbate his or her emotional depression with the expectation that (s)he might not get what (s)he deserves despite his or her time and effort put into achieving such goals. This study also adds further boundary conditions to these effects, such that the decrease of emotional depression is more pronounced when (1)social capital and (2)economic resources are scarce (versus abundant). To test these predictions, this study used the survey data on a total of 8000 people collected by Gallup Korea at the request of the Korea Institute of Public Administration. The analyses provided support for the proposed model of the present study. These results should contribute to laying the theoretical foundation for the establishment of policies and research models on the enhancement of fairness and prevention of depression in the future.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.25 no.1
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• pp.11-23
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• 2022

This study aims to systematically review the candidate types for OECMs suitable for domestic conditions in areas related to the Korea Forest Service in order to achieve the goal of establishing the protected areas and OECMs system required by Post-2020 GBF, and to provide basic data for the establishment of the national protected areas system. As a result of the study, the selection criteria for OECMs were presented, and it was found that arboretums·botanical gardens, Natural Recreation Forests, and air holes may correspond to the Candidate Types for OECMs. As a result of evaluating the possible areas for OECMs based on the OECMs selection criteria, in the case of arboretums·botanical gardens, it is judged that only conservation areas can be designated as OECMs, except for areas mainly used by visitors of arboretums·botanical gardens that fall under the BGCI conservation type among national and public arboretums·botanical gardens. However, private and school arboretums·botanical gardens have personal property ownership, so it was judged to have no effective measures to control activities that may adversely affect biodiversity, which showed limitations in designation of OECMs. Natural Recreation Forests was found to meet the OECMs selection criteria. However, private forests have personal property ownership, which limits the designation of OECMs. Therefore, it is necessary to strengthen the function of in-situ conservation in order to meet the OECMs for private and school arboretums·botanical gardens, and private forests that have personal property ownership. To this end, effective measures are needed to achieve biodiversity conservation outcomes, and it is judged that legal control and corresponding support policies (incentives) are needed. In the case of air holes, for sustainable conservation, the management boundary of air holes should be clearly defined based on the preparation of laws and guidelines related to air holes. In addition, it is judged that it is desirable to designate the competent local forest office as the management authority and conduct periodic detailed surveys of air holes, establish and implement the conservation plans based on those.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.27 no.1
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• pp.33-47
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• 2022

In this study, distribution of submarine sand ridges in the coastal waters of Korea was surveyed using multibeam echo sounder data, and the topographic characteristics of each region were identified. For this purpose, the DEM (Digital Elevation Model) data was generated using depth data obtained from the Yellow Sea and the South Sea by Korea Hydrographic and Oceanographic Agency, and then applied the TPI (Topographic Position Index) technique to precisely extract the boundary of the sand ridges. As a result, a total of 200 sand ridges distributed in the coastal waters were identified, and the characteristics of each region of the sedimentary sediments were analyzed by performing statistical analysis on the scale (width, length, perimeter, area, height) and shape (width/length ratio, height/width ratio, linear·branch type, exposure·non-exposure type). The results of this study are expected to be used not only for coastal navigational safety, but also for marine naming support, marine aggregate resource identification, and fisheries resource management.

• Trans-
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• v.15
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• pp.81-104
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• 2023

This paper analyzes the danmu phenomenon with the concept of participatory culture proposed by Henry Jenkins. Unlike other comments, Danmu is a function that allows users to post anonymously while watching a video, and comments posted at that time are immediately displayed on the screen and can be viewed by other viewers. The service was first launched by Niconico. In this paper, the danmu phenomenon in the Chinese video platform Bilibili is analyzed by focusing on three aspects. First, in terms of creative sharing under collective intelligence, we explore how users create their own creations and share them with other users through danmu. Second, in the collaboration model under public participation, the method and meaning of collective cooperation through users' interaction is dealt with. Third, in terms of financial support of commercial capital, the influence of danmu videos to create commercial profits is analyzed as a case. In addition, the negative aspects and challenges of participatory culture in Bilibili are analyzed. Negative aspects such as participation gap, copyright infringement, excessive use of danmu and problems of anonymity were reviewed, and major challenges to realize the potential of danmu as a participatory culture were suggested. This paper comprehensively analyzes danmu using research methods such as literature review and case studies, and through this, tries to derive insights on how participatory culture and danmu interact and evolve in modern society. Danmu, as a participatory medium, is an important tool that promotes individual and collective creation and interaction, and is pioneering a new boundary between the media industry and its users.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.6A
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• pp.525-534
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• 2010

A road curbstone is a structure installed at the boundary of the sidewalk and the street with the objectives of road drainage, drawing attention and such. The current general construction method of curbstones places foundation concrete for the curbstones first, waits until the concrete reaches the strength to support the curbstones, places the curbstones on top, and then places the gutter and rear filling concrete. Such method has the issues of poor compaction and weakened bond strength of concrete due to split placing of concrete, and causes the curbstones to easily separate due to vehicle impact or earth pressure, in turn creating maintenance costs and spoiling the aesthetics. To improve such conventional construction methods, an all-in-one method was developed using formwork rail and jig where both the curbstones and gutter can be worked at the same time, and to evaluate the structural performance, static tests of lateral loading test, pullout test, and bending test were executed, and dynamic tests such as pendulum test and actual vehicle impact test were executed. In all tests, the all-in-one construction method using formwork rail and jig was shown to be superior to the conventional construction method by the increase of construction quality and bond strength of concrete.

• The Journal of Korean Philosophical History
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• no.29
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• pp.179-202
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• 2010

In addition to the emphasis on filial piety ethics in everyday life, filial piety obtained a further significance in Confucianism which had the strong sense of ancestor worship. This paper focuses on filial piety as a mechanism of continuity within Confucianism and points out that it owed its development to its connection to agricultural culture. The sedentary life with less mobility forged a relative intimacy among people and filial piety was the actual expression of that kind of intimate affection. Yet, filial piety in Confucianism created a unique culture in terms that it not only stipulated material and emotional support for parents but also expected one's piety to the further ancestors through a memorial service and made its connection to the infinite posterity through sons. From the perspective of Confucianism that established filial piety at the turning point from life to death, the self existing in present was not an isolated self anymore. Yet, one can see another characteristic of Confucianism from that filial piety, based on blood bonds, could move beyond paternalism to broaden itself. It could be expanded to the care for strangers. The aged experience and wisdom through agricultural life begot the insight that the nature made its infinite connections with everything through circulation. As a stone thrown in a pond would enlarge its boundary by drawing larger and larger concentric circles, this thought enabled people to enlarge their affection to their parents to universal humanity. In this enlarged network, though it was natural to make distinctions between the closer and the farther, Confucianism sought to overcome it by establishing oneself upright. Confucianism emphasized the moral cultivation with its filial piety concept that contained the diachronic thought penetrating life and death and the broadened perspective relating everything around. In Confucianism, filial piety provided an important medium in forming a moral subject that penetrated life and death and related self and others. Inherent in it is the Confucius thought of continuity that searched for a paragon of a moral human being regardless of time and space.