• Title/Summary/Keyword: phase space

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A Study on the Development Method of e-Learning Contents by the Level of Demand for Landscaping Practical Education - Development and Reuse of Modular Learning Objects - (조경실무 교육수요 수준별 이러닝 콘텐츠 개발 방법론 - 모듈형 학습객체 개발과 재사용을 중심으로 -)

  • Choi, Ja-Ho
    • Journal of the Korean Institute of Landscape Architecture
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    • v.46 no.3
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    • pp.1-13
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    • 2018
  • Landscape Architecture is a minority manpower field that requires wide knowledge and experience. Therefore, the service market is narrower than other fields, and education service for practitioners is lacking. The purpose of this study is to propose e-learning content development methodology that can provide customized landscaping practical education according to the level of education and increase the economic efficiency of the development process. First, in theoretical review, the ADDIE model was modified to select the curriculum development model that pursues efficiency and introduced the concept of reusing learning objects in the SCORM-based model. In particular, to overcome the problems presented in the precious studies, the analysis and design stages have been strengthened and faculty designers with integrated knowledge of Landscape Architecture and ICT have led the overall phase. The actual development process is based on a step by step procedure--analysis of landscaping practitioners needs and environments, etc., teaching and learning procedures and the design of activities considering contents reuse, the first development such as actual shooting and editing, and the second development reusing the first development content--and was done in the order of evaluation and revision of professionalism and satisfaction. As a result of the study, the space-based courses composed of modular learning objects were first developed as 216 courses in 8 subjects, as 208 courses in 3 subjects in total, in which the modularized learning object are crossed and combined in units and difficulty-based courses were second developed in 216 courses with 3 subjects in total. As a result of the evaluation the satisfaction assessment of the overall satisfaction was 4.20 and the average value of the eight measures was 3.97, both being close to 4.0. For the professional assessment, the scores of 8 subjects were very high at 84.8 to 96.4 points. in context, the scores of 5 subjects were equal to from 89.9 to 96.4 points. In conclusion, as the study was conducted based on a clear understanding of the digital characteristics of e-learning contents and general characteristic of the landscaping industry, it was possible to develop a curriculum by developing a course composed of modular learning objects and reusing learning objects by unit. In particular, it has been proven to be effective in conveying professional knowledge and experiences via general procedures and provided an opportunity to overcome some analog problems that may occur in offline education. In the future, further studies need to be done by expanding the content and by focusing on segmented subjects.

Design Strategies and Processes through the Concept of Resilience (리질리언스 개념을 통해서 본 설계 전략과 과정)

  • Choi, Hyeyoung;Seo, Young-Ai
    • Journal of the Korean Institute of Landscape Architecture
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    • v.46 no.5
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    • pp.44-58
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    • 2018
  • Cities face new challenges not only in natural disasters by climate change but also in social and economic fluctuations. With the existing simple reconstruction method, it is difficult to solve the overall problems that a city or region may face. As a new approach to cope with various changes, the concept of resilience is emerging. Resilience is also one of the themes of recent major urban design projects. Design with the concept of resilience is a new strategy that can deal with various changes of urban space, rather than a temporary trend. The purpose of this paper is to explore the design method by analyzing cases where the concept of resilience is employed. We aim to examine what kind of design strategies are needed for the resilience design and how this design process differ in character, as compared to general design projects. Cases for this study include the "Rebuild by Design" competition held in 2013 and the "Resilient by Design/Bay Area Challenge" competition held in 2017. This paper consists of literature reviews and case studies. The latter is divided into two aspects: content analysis based on the theory of resilience and characteristics of the design process. Cases are analyzed through literature reviews and process characteristics of resilience design in response to the general design process. The main categories for urban resilience used as the framework for analysis include: Urban Infrastructure, Social Dynamics, Economic Dynamics, Health and Wellbeing, Governance Networks, and Planning and Institutions. As a result, the aspects of resilience concepts considered and design strategies undertaken by each team were identified. Each team tried to connect all 6 categories to their design strategies, placing special value on the role of governance, a system that enables collaborative design and project persistency. In terms of the design process, the following characteristics were found: planning the whole project process in the pre-project phase, analyzing predictable socioeconomic risk factors in addition to physical vulnerabilities, aiming for landscape-oriented integrated design, and sustainable implementation strategies with specific operations and budget plans. This paper is meaningful to connect the concept of resilience, which has been discussed in various articles, to design strategy, and to explore the possibility of constructing a practical methodology by deriving the characteristics of the resilience design process. It remains a future task to research design strategies that apply the concept of resilience to various types of urban spaces, in addition to areas that are vulnerable to disasters.

Application of Earthworm Casting-derived Biofilter Media for Hydrogen Sulfide Removal (지렁이 분변토를 이용한 생물담체가 충전된 바이오필터에 의한 황화수소 제거)

  • Yoo, Sun-Kyoung;Lee, Eun-Young
    • Journal of Korean Society of Environmental Engineers
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    • v.29 no.7
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    • pp.820-825
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    • 2007
  • Earthworm casting was the natural fertilizer that contained high concentrations of nutrients such as nitrogen, phosphate and potassium and of over $10^8$ CFU/ml of microorganisms. Greater than 80% of feed was excreted through the fermentation by the intestinal enzyme, after worm had eaten feeds such as fallen leaves and rotten roots under the ground. Also, the soil structure of casting was known to be very efficient in the aspects of the porosity, the water permeability, and deodorizing activities. In this research, the biofilter packed with a biomedia made of casting and waste polyurethane foam, a binder, which helped to improve the durability and perpetuity of casting, was investigated to degrade malodorous hydrogen sulfide gas. The biomedia had no need of extra supply of nutrients and of microbial inoculations. On the beginning of the operations, it showed 100% removal of hydrogen sulfide gas without lag phase. At SV of 50 $h^{-1}$, hydrogen sulfide gas from the outlet of the biofilter was not detected, when inlet concentration increased to 450 ppmv. After that, removal efficiency decreased as increasing inlet hydrogen sulfide concentration. Hydrogen sulfide removal was maintained at almost 93% until inlet concentration was increased up to 950 ppmv, at which the elimination capacity of $H_2S$ was 61.2 g $S{\cdot}m^{-3}{\cdot}h^{-1}$. Maximum elimination capacity guaranteing 90% removal was 61.2, 65.9, 84.7, 89.4 g $S{\cdot}m^{-3}{\cdot}h^{-1}$ at SV ranging from 50 $h^{-1}$ to 300 $h^{-1}$, but was 59.3 g $S{\cdot}m^{-3}{\cdot}h^{-1}$ at SV of 400 $h^{-1}$. The results calculated from Michaelis-Menten equation revealed that $V_m$ increased from 66.04, 88.96, 117.35, 224.15, to 227.54 g $S{\cdot}m^{-3}{\cdot}h^{-1}$ with increasing space velocity in the range of 50 $h^{-1}$ to 400 $h^{-1}$. However, saturation constant$(K_s)$ decreased from 79.97 ppmv to 64.95 and 65.37 ppmv, and then increased to 127.72 and 157.43 ppmv.

Studies on the Construction Characteristics of Rear Garden Farmland at Joseon Palace (조선시대 궁궐 후원 농경지(農耕地) 조영의 특성)

  • Jung, Woo-Jin;Sim, Woo-Kyung
    • Journal of the Korean Institute of Landscape Architecture
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    • v.40 no.4
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    • pp.62-77
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    • 2012
  • This study aimed to investigate the Confucian-oriented agriculture phase of the Joseon Dynasty, which was reflected at the palaces, by analyzing constructional aspects and spatial characteristics of farmlands at the palace rear gardens. The objective sites were the rear gardens of Gyeongbok Palace, Changkyung Palace, and the outside of Sinmoomoon(神武門) This study was based on literature reviews. The farmlands at the palace rear garden were constructed to self-estimate the year's harvest condition within the palaces. It was a part of the agriculture encouragement policy on governing the group of Joseon like publishing the Nongsajiksul(農事直說) and establishing the Chingyeongnye(親耕禮: king's own cultivation ceremony) and Kikokje(祈穀祭: the rite of praying for grain). In addition, farmlands of the rear garden were operated from the beginning of the state almost until the Japanese colonial era. The results were summarized as follows: First, Gyeongbok Palace rear garden's farmland which begin at the reign of Sejong(世宗) existed at the present Hyangwonji(香遠池) area. It was constructed in order to check the advanced agricultural technologies. The rear garden's farmland in Changkyung Palace, which was executed during the reign of Seongjong(成宗), was constructed right after the initial Chingyeongnye of the Joseon Dynasty. Therefore, it might be understood as the context of the king's own cultivation of the Jeokjeonchinkyung(籍田親耕). Injo(仁祖) dug for farmland in the ground of the Gyemgdeok Palace(慶德宮) though there was some stay palace, when his stay dragged out for too long. This bespeaks that those farmlands at the palace rear gardens were of great importance in the Joseon political history. The farmland near Gyeongnongjae(耕農齋), which was made during the reign of Gojong(高宗), inherited predecessor's walks of the promoting agriculture and exhibited spatial compositions such as the rear garden's farmland at Changkyung Palace. Secondly, irrigation, its water systems, the name of observatory to study farming[觀耕臺] and location requirements for farmland had something in common. It was assumed as universal forms of physiocracy-space in the Joseon Dynasty. In this study, by considering aspects of operating about vegetable garden managed by eunuchs and of the orchard in palace to cultivate fruits for national ceremonies, it could be assumed that landscape architecture of royal palace in the Joseon Dynasty did not only focus on solemnity, orderliness and fanciness but also on the practical and productive which was helpful in life. In addition, the diverse activities of productive landscape architecture led by the royal family in palaces, and the initiatively tested advanced agricultural technologies by the king were considered as an aspect of the Korean traditional specific royal palace landscape architecture. That is considered sole landscape not only to love of the people but also the 'agriculture-first' principle which were absent from other nations.

Geochemistry and Genesis of Hydrothermal Cu Deposits in the Gyeongsang Basin, Korea : Hwacheon-ri Mineralized Area (경상분지내 열수동광상의 지화학 및 성인연구 : 화천리지역 광화대)

  • So, Chil-Sup;Choi, Sang-Hoon;Yun, Seong-Taek
    • Economic and Environmental Geology
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    • v.28 no.4
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    • pp.337-350
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    • 1995
  • The Hwacheon-ri mineralized area is located within the Cretaceous Gyeongsang Basin of the Korean peninsula. The mineralized area includes the Hwacheon, Daeweon, Kuryong and Cheongryong mines. Each of these mines occurs along copper-bearing hydrothermal quartz veins that crosscut late Cretaceous volcanic rocks, although some disseminated ores in host rocks also exist locally. Mineralization can be separated into three distinct stages (I, II, and III) which developed along preexisting fracture zones. Stage I is ore-bearing, whereas stages II and III are barren. The main phase of ore mineralization, stage I, can be classified into three substages (Ia, Ib and Ic) based on ore mineral assemblages and textures. Substage Ia is characterized by pyrite-arsenopyrite-molybdenite-pyrrhotite assemblage and is most common at the Hwacheon deposit. Substage Ib is represented by main precipitation of Cu, Zn, and Pb minerals. Substage Ic is characteristic of hematite occurrence and is shown only at the Kuryong and Cheongryong deposits. Some differences in the ore mineralization at each mine in the area suggest that the evolution of hydrothermal fluids in the area varied in space (both vertically and horizontally) with respect to igneous rocks relating the ore mineralization. Fluid inclusion data show that stage I ore mineralization mainly occurred at temperatures between ${\approx}350^{\circ}$ and ${\approx}200^{\circ}C$ from fluids with salinities between 9.2 and 0.5 wt.% eq. NaCl. In the waning period of substage Ia, the high temperature and salinity fluid gave way to progressively cooler, more dilute fluids of later substage Ib and Ic (down to $200^{\circ}C$, 0 wt.% NaCl). There is a systematic decrease in the calculated ${\delta}^{18}O_{H2O}$ values with paragenetic time in the Hwacheon-ri hydrothermal system from values of ${\approx}2.7$‰ for substage Ia, through ${\approx}-2.8$‰ for substage Ib, to ${\approx}-9.9$‰ for substage Ic. The ${\delta}D$ values of fluid inclusion water also decrease with decreasing temperature (except for the Daeweon deposit) from -62‰ (substage Ia) to -80‰ (substage Ic and stage III). These trends are interpreted to indicate the progressive cooler, more oxidizing unexchanged meteoric water inundation of an initial hydrothermal system which is composed of highly exchanged meteoric water. Equilibrium thermodynamic interpretation of the mineral assemblages with the variation in amounts of chalcopyrite through the paragenetic time, and the evolution of the Hwacheon-ri hydrothermal fluids indicate that the solubility of copper chloride complexes in the hydrothermal system was mainly controlled by the variation of temperature and $fo_2$ conditions.

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A Study of Deconstruction in Clothing -Comparison of Clothing with Architecture- (복식에 나타난 해체주의 양식연구 -건축과 복식의 비교-)

  • 전혜정
    • Journal of the Korean Society of Costume
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    • v.32
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    • pp.293-312
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    • 1997
  • Deconstructionism is a philosophical stream in the latter half of 20'th century which goes against western metaphysics and tries to deconstruct the dualism e.g. eastern/west-ern man/woman. Its main concepts are 'indi-vidual' 'other' 'difference' 'restoration of the repressed' 'decentralization' 'Today it shows strong influences in literature art, and other social fields. This study investigated inner meanings and exterior forms represented in clothing on the base of Jacques Derrida's theory in order to re-search modes of deconstruction in is. And it compared clothing with architecture among other genres of art in order to discover similarities between through and modes of art in a certain period. For illuminating concept of deconstruction I referred to the literatures of preceding studies and for deconstruction's characteristics in both clothing and architec-ture I referred work's collection book $\ulcorner$collec-tions$\lrcorner$ and other related books dealing from 1960's to this point. As a rsult there are four modes of decons-truction in both clothing and architecture as follows; 1) Differenance which is a concept of the dif-ference in time and space as being trace. 2) In termeaning of meanings which is not present in reality but re-interpreted a new in the future. 3) Interxtuality in which a texte is not alone but with others 4) Dis.De phenomenon in which distortion and fragmentation forms occur as the result of the denial of perfection and reson. There are characteristics of modes of de-construction in clothing as follows; 1) Differance; R.Gigli, P. Rabanne. G.Bersace, V.Westwood are representatives of the cloth-ing which is combined with the past the pres-ent and the future or is re-viewed as the clothing of the past in the present point of view. J. Watanabe R. Dawakubo I miyake are representatives of the clothing which is out-date but re-viewed in the sense of recollec-tion and re-usage. 2) Intermeaning of meanings: R. kawakubo I, Miyake Y,Yamamoto are representatives of the clothing which is incomplete but re-interpreted in the future and appears to be new-fashioned according to ways of bnding wearing throwing on and tying J.C. Castel-bajac K.Hamnett S.Sprouse are representa-tives of the clothing which is made up of ab -stract forms scribbling or symbolic letters which appears to be different according to view-point of observers. 3) Intertextuality ;J.P.Gaultier K.Hamnett, Comme des Gar ons are representatives of intertextuality of gender which avoids the 여-ality of man/woman J.P Gaultier G,Versace J. galliano are representatives of the intertex-tuality of time place and occasion which mixes temporality extensity and purposiveness. J.P Gaultier G,Versace are representatives of the intertextuality of coordination which combines items different in image purpose and use. P.Rabanne A,Courr ges R,Gernreic I,Miyake are representatives of the intertextuality of mat-ter which uses heterogeneous matter different from cloth. 4) Dis.De-phenomenon: R, Kawakubo I.Mi-yake J.P.Gaultier are representatives of the de-composition which discloses distortion and exag-geration of form through destructing the estab-lished way of construction J.Galliano R.Kawa-kubo Devota Y Lomba arte representatives of the decentring which restores the repressed and the alienated on the one hane and shows front-centrality on the other. Comme des Gar ones is representative of the discontinuity because of which right and left up and down are not in har-mony with one another. J,Galliano J.P,Gaultier T,Mugler are representatives of the disruption by way of which one makes one's body exposed through intentional slashes or holes. As a consequence deconstructionism enabled us to investigate similarities between through of deconstruction and modes of art interms of diffrance Intermeaning of meanings intertextuality and Dis De-phenomenon. And we found that deconstruction was a phase of development in that it as a all-comprising and multiple concept tries to pursue the new through deconstruction.

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A Study on the Visual Characteristics and The Principal of Formation of ChangSayng-Do in the Late Chosun Dynasty (조선 후기 장생도(長生圖)의 구성원리와 조형적 특성)

  • Kim Jun-Keun
    • Journal of Science of Art and Design
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    • v.8
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    • pp.63-94
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    • 2005
  • ChangSayng-Do in the late Chosun dynasty was a kind of traditional painting which sublimated the philosophy and emotion of everyday life into an aesthetic consciousness through a long history of Korean people . It would represent a human wish and desire to live a long and healthy life, which was implicated by way of Taoism. The major themes of ChangSayng-Do - mountains, the sun, cloud, water, rock, deer, tortoises, cranes, pine trees, bamboos, peaches, and herbs of eternal youth - were all symbols used. to wish for a long-life and immortality in real world. All or some of these items were represented in paintings, which resulted in the various kinds of ChangSayng-Do. The main concern of this thesis will be centered around the naturalistic subjects shown in ChangSayng-Do. This thesis consists of four chapters. The first chapter describes the purpose of and need for the research, and its method and scope. The second chapter deals with the origin and style of ChangSayng-Do, and the background of its formation. It is found out that the formative characteristic of ChangSayng-Do lies in the archetype, the unity of man and nature following the traditional view of nature. It is also found out that ChangSayng-Do implied the notions of Supernatural Being, Yin-Yang and Five Elements, Taoism, and Confucianism as well as Korean shamanism. Third chapter is largely about an analytic investigation into symbolic visualization of ChangSayng-Do. Firstly, the subject matters shown in ChangSayng-Do consist of items of wishful omen for long-life and good luck, and any motif in a picture implies a symbolism of eternal youth and long-life. Secondly, the view of colors shown in ChangSayng-Do is closely connected to Five Elements and Five Direction, a traditional oriental philosophy of universe, and these symbolic colors are based on shamanism and Yin/Yang-Five Elements. According to an iconological analysis, it is confirmed that these viewpoints are consistent with formative principles and expressive methods of ChangSayng-Do to some extent. The fourth chapter is one of the most important elements for visualization of ChangSayng-Do. The symbolic meaning of long life and good luck is the major source of its popularity inside the palace as well as among the people in general. The fact that ChangSayng-Do was used to ornament the palace was documented in $\lceil$UiGuey(documents about Chosun dynasty$\rfloor$. Also during the late period of Chosun dynasty, the appreciators of arts had begun to spread from high level class to lower level class, and many pictures represented in $\lceil$Hanyang-Ga$\rfloor$ were the ones produced and circulated for those increased consumers. As for the folk-artistic characteristics, the anonymity and arbitrary naturalness of ChangSayng-Do demonstrates that the folk-artistic elements were fully soaked into the life styles of people in general. ChangSayng-Do further shows that a human being is located in the center of the universe, and that all the natural phenomena and ecology are observed to happen around human beings, and that the results of those happenings are connected to man's course of life. It is discovered that the subject matters of ChangSayng-Do in the late Chosun dynasty imply another idea inside metaphors and symbols. With regard to the arrangement of time and space, the unity or oneness of oneself with the world is more highly regarded than one's individual subjectivity: there exist multiple times and spaces in a single picture This reveals a wholistic view of oneness which does not permit the division between phenomenon and substance. To conclude, this thesis inquired into ChangSayng-Do in the late Chosun dynasty focusing on the expression of archetype-symbols. And through the analysis and demonstration, this thesis re-established constructional principles and formative characteristics of ChangSayng-Do and then settled a new phase of ChangSayng-Do, with a deep under-standing of fundamental thoughts of Korean people underlying ChangSayng-Do.

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The Microalgal Attachment and its Growth on the Artificial Surfaces Immersed in Seawater: I. Attachment and Micro-succession (해수에 잠긴 인공기질 표면에서 미세조류의 부착과 성장: I. 부착 및 천이)

  • Shim, Jae-Hyung;Kang, Jung-Hoon;Cho, Byung-Cheol;Kim, Woong-Seo
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.3 no.4
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    • pp.249-260
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    • 1998
  • To understand the attachment of micro algae and their subsequent growths on artificial surfaces immersed in seawater, the relationship between attachment of diatoms on the immersed artificial substrates and species pool in the surrounding water was investigated. We used acryl slides for the study of diatom attachment and examined the surrounding water samples collected in Incheon Harbour from July 1995 to February 1997. Variations of species composition and abundances by exposure time in seawater were investigated during the early phase of biofilm formation on various substrates, e.g. glass, acryl, titanium, copper and antifouling paint-treated slides. Immigration rates of diatoms to acryl slides during spring and winter were significantly correlated with the abundance of benthic diatoms in surrounding water ($r^2$=0.78, p<0.01, n=42), suggesting that immigration rates were affected by variations of benthic diatom abundances in surrounding water. Immigration coefficient of monoraphid diatoms was 5 times higher than that of biraphid diatoms, but relative abundance of monoraphid diatoms was 3 times lower than that of biraphid diatoms on acryl slides in spring. In winter, immigration coefficient and relative abundance of centric diatoms were higher compared to other raphe forms. These results suggest that the attachment of diatoms seems to be caused by the abundance and immigration coefficients of benthic diatoms in surrounding water. Pennate diatoms predominantly attached to all artificial surfaces throughout all experimental periods. Interestingly, centric diatoms predominantly attached to all artificial surfaces in winter. Hantzschia virgata, Licmophora abbreviata and Melosira nummuloides appeared dominantly on antifouling paint-treated slides, probably being tolerant of the antifouling paint. During incubations, the abundance of attached diatoms increased exponentially on glass, titanium and acryl slides with exposure time. The maximum abundance was highest on glass slide, followed by acryl, titanium, copper and antifouling paint-treated slides. The growth rates of attached diatom community on all artificial surfaces were higher at temperature of $24-25^{\circ}C$ than that of $2-3^{\circ}C$. The growth rate of attached diatoms on glass slide was generally higher compared to other slides during the study period. Dominant morphotypes of observed species with exposure time in seawater were prostrate form Amphora coffeaeformis, fan shape Synedra tabulata, stalk type Licmophora paradoxa and chain type M. nummuloides. A micro-succession in the attached microalgal community was observed. The composition of dominant species seems to be the result of species-specific response to gradually limited space with development of microalgal film.

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Numerical Modelling for the Dilation Flow of Gas in a Bentonite Buffer Material: DECOVALEX-2019 Task A (벤토나이트 완충재에서의 기체 팽창 흐름 수치 모델링: DECOVALEX-2019 Task A)

  • Lee, Jaewon;Lee, Changsoo;Kim, Geon Young
    • Tunnel and Underground Space
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    • v.30 no.4
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    • pp.382-393
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    • 2020
  • The engineered barrier system of high-level radioactive waste disposal must maintain its performance in the long term, because it must play a role in slowing the rate of leakage to the surrounding rock mass even if a radionuclide leak occurs from the canister. In particular, it is very important to clarify gas dilation flow phenomenon clearly, that occurs only in a medium containing a large amount of clay material such as a bentonite buffer, which can affect the long-term performance of the bentonite buffer. Accordingly, DECOVALEX-2019 Task A was conducted to identify the hydraulic-mechanical mechanism for the dilation flow, and to develop and verify a new numerical analysis technique for quantitative evaluation of gas migration phenomena. In this study, based on the conventional two-phase flow and mechanical behavior with effective stresses in the porous medium, the hydraulic-mechanical model was developed considering the concept of damage to simulate the formation of micro-cracks and expansion of the medium and the corresponding change in the hydraulic properties. Model verification and validation were conducted through comparison with the results of 1D and 3D gas injection tests. As a result of the numerical analysis, it was possible to model the sudden increase in pore water pressure, stress, gas inflow and outflow rate due to the dilation flow induced by gas pressure, however, the influence of the hydraulic-mechanical interaction was underestimated. Nevertheless, this study can provide a preliminary model for the dilation flow and a basis for developing an advanced model. It is believed that it can be used not only for analyzing data from laboratory and field tests, but also for long-term performance evaluation of the high-level radioactive waste disposal system.

Characteristics of NO Oxidation Using NaClO2 (NaClO2를 이용한 NO 산화 특성)

  • Lee, Kiman;Byun, Youngchul;Koh, Dong Jun;Shin, Dong Nam;Kim, Kyoung Tae;Ko, Kyoung Bo;Cho, Moohyun;Namkung, Won;Mok, Young Sun
    • Korean Chemical Engineering Research
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    • v.46 no.5
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    • pp.988-993
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    • 2008
  • The characteristics of NO oxidation using sodium chlorite ($NaClO_2$) powder have been investigated by a flow type packed-bed reactor, where the reaction temperature and the space velocity are varied in the range of $20{\sim}230^{\circ}C$ and $0.4-2.2{\times}10^5hr^{-1}$, respectively, and the simulation gas mixtures are composed of NO (0~200 ppm), $NO_2$ (0-200 ppm), $O_2$ (0~15%) and $H_2O$ (0~15%) within $N_2$ balance. It has been found that the oxidation efficiency of NO depends greatly on the reaction temperature, exhibiting the existence of critical reaction temperature at about $170^{\circ}C$ where the oxidation efficiency of NO is maximized and then abruptly decreased with further increase of reaction temperature, resulting in being negligible over $190^{\circ}C$. Such a behavior in the oxidation efficiency has been originated from the phase transition of $NaClO_2$ at about $170^{\circ}C$ to form $NaClO_3$, and NaCl which are chemically inactive toward the oxidation of NO. The chemical reaction of NO with $NaClO_2$ has been observed to produce $NO_2$, ClNO and $ClNO_2$, whereas that of $NO_2$ only OClO species. Additionally, we have also observed that the introduction of $O_2$ and $H_2O$ has little influence on the oxidation of NO.