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Analysis of Fish Ecology and Water Quality for Health Assessments of Geum - River Watershed (금강본류의 건강성 평가를 위한 어류생태 및 수질 특성분석)

  • Park, Yun-Jeong;Lee, Sang-Jae;An, Kwang Guk
    • Korean Journal of Environment and Ecology
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    • v.33 no.2
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    • pp.187-201
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    • 2019
  • This study examined the physicochemical water quality and evaluated the ecological health in 14 sites of Geum River (upstream, mid-stream, and downstream) using the fish community distribution and guilds and eight multi-variable matrices of FAI (Fish Assessment Index) during June 2008-May 2009. The analysis of the water quality variables showed no significant variation in the upstream and mid-stream but a sharp variation due to the accumulation of organic matter from the point where the treated water of Gap and Miho streams flew. The analysis of physicochemical water properties showed that BOD, COD, TN, TP, Cond, and Chl-a tended to increase while DO decreased to cause eutrophication and algae development from the downstream where Miho and Gap stream merged. The analysis of fish community showed that the species richness index and species diversity index increased in the mid-stream area but decreased in the downstream area, indicating the stable ecosystem in the upper stream and the relatively unstable ecosystem in the downstream. The analysis of the species distribution showed that the dominant species were Zacco platypus that accounted for 20.9% of all fish species and Zacco koreanus that accounted for 13.1%. The analysis of the fish tolerance and feeding guild characteristics showed that the sensitive species, the insectivore species, and the aquatic species were dominant in the mid-stream point. On the other hand, contaminants from the sewage water treatment plant of Miho stream had a profound effect in the downstream to show the dominance of tolerant species, omnivorous species, and lentic species. Therefore, it is necessary to improve water quality by reducing the load of urban pollutants and to pay attention to the conservation and restoration of aquatic ecosystems.

Biodiversity and Characteristic Communities Structure of Freshwater Ecosystems in the Western Area of DMZ, Korea (민통선이북지역(DMZ) 서부평야 일대의 수생태계 생물다양성 및 군집 특성)

  • Jung, Sang-Woo;Kim, Yoon-Ho;Kim, Hyun-Mac;Kim, Su-Hwan
    • Korean Journal of Environment and Ecology
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    • v.32 no.6
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    • pp.603-617
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    • 2018
  • This study surveyed the diversity and community characteristics of benthic macroinvertebrates and freshwater fish, which are the main animal classifications in a hydro ecosystem, from May to September 2017 in the western plains of the Demilitarized Zone (DMZ). The results showed a total of 125 species of benthic macroinvertebrates belonging to 66 families, 19 orders, and four phyla in the streams and wetlands. Among benthic macroinvertebrates, Coleoptera (27 spp.: 21.60%) was the largest group in terms of species richness followed by Odonata (26 spp.: 20.80%), non-Insecta (22 spp.: 17.60%), and Hemiptera (11 spp.: 8.80%) occupying in the lentic area. Of the feeding function groups (FFGs), predators (51 spp.: 56.67%) showed a relatively larger presence, indicating the dominance of hygrophilous invertebrates that usually inhabit the freshwater wetlands or ponds. Of the habitat oriented groups (HOGs), climbers (33 spp.: 24.44%) and burrowers (17 spp.: 12.59%) were the dominant groups. This observation is typical in a slow flowing habitat and can lead to the disturbance of the ecosystem due to cannibalism among predators. Cannibalism can be caused by stress induced by various population and environmental factors. For the ecosystem services benchmark (ESB) value, site 13 appeared to be the highest with 82 marks while other sites showed relatively lower rates and indices (III water quality class with ${\alpha}$-mesosaprobic). The analysis result of stability factors showed that almost all sites were evaluated to be the I characteristic group with high resilience and resistance or the III characteristic group that was sensitive to environmental disturbance and formed uneven and unstable communities. Of the freshwater fishes, 46 species (3,405 individuals) belonging to 39 families and 18 orders were identified in all the investigated sites. Among them, Cyprinidae (30 spp.: 65.2%) was the largest group, and Zacco koreanus was identified as the dominant species (728 individuals, 21.4%). The survey of freshwater fish communities found both stable communities (sites 7 and 13) with low dominant index (0.39) and high diversity index (2.29) and unstable communities (sites 2, 3, 8, and 10) in opposite tendency. This survey found five Korean endemic species, 17 species belonging to the export controlled species, two endangered species level II (Lethocerus deyrollei and Cybister chinensis), and rare species (Dytiscus marginalis czerskii) among benthic macroinvertebrates. The survey also found an invasive species, Ampullarius insularus, which was distributed throughout the whole area and thus can continuously disturb the ecosystem in the western plain area in the DMZ. Of freshwater fish, one natural monument (Hemibarbus mylodon) and three endangered species level II (Acheilognathus signifer, Gobiobotia macrocephalus, and G. brevibarba) were observed. The survey also found four introduced species (Pomacea canaliculate, Carassius cuvieri, Lepomis macrochirus, Micropterus salmoides) in the western DMZ area, indicating the need for the protection and conservation measures.

The Formation and Types of Business Archives m Germany (독일 경제아카이브즈의 형성과 유형)

  • Kim, Young-Ae
    • The Korean Journal of Archival Studies
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    • no.8
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    • pp.137-180
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    • 2003
  • The term 'Business Archives' is not familiar with us in our society. Some cases can be found that materials are collected for publishing the history of a firm on commemoration of some decades of its foundation. However, the appropriate management of these collected materials doesn't seem to be followed in most of companies. The Records and archives management is inevitable in order to maximize the utility of Information and knowledge in the business world. The interest in records management has been grown, especially in the fields of business management and information technology. However, the importance of business archives hasn't been conceived yet. And also no attention has been paid to the business archives as social resources and the responsibility of the society as a whole for their preservation. The company archives doesn't have a long history in Germany although the archives of the nation, the aristocracy, communes and churches have a long tradition. However the company archives of Krupps which was established in 1905, is regarded as the first business archives in the world, It means that Germany has taken a key role to lead the culture of business archives. This paper focuses on the process of the establishment of business archives in Germany and its characteristics. The business archives in Germany can be categorized in three types: company archives, regional business archives and branch archives. It must be noted here that each type of these was generated in the context of the accumulation of the social resources and its effective use. A company archives is established by an individual company for the preservation of and use of the archives that originated in the company. The holdings in the company archives can be used as materials for decision making of policies, reporting, advertising, training of employees etc. They function not only as sources inside the company, but also as raw sources for the scholars, contributing to the study of the social-economic history. Some archives of German companies are known as a center of research. A regional business archives manages materials which originated m commerce chambers, associations and companies in a certain region. There are 6 regional business archives in Germany. They collect business archives which aren't kept in a proper way or are under pressure of damage in the region for which they are responsible. They are also open to the public offering the sources for the study of economic history, social history like company archives, so that they also play a central role as a research center. Branch business archives appeared relatively late in Germany. The first one is established in Bochum in 1969. Its general duties and goals are almost similar with ones of other two types of archives. It has differences in two aspects. One is that the responsibility of the branch business archives covers all the country, while regional business archives collects archives in a particular region. The other is that a branch business archives collects materials from a single industry. For example, the holdings of Bochum archives are related with the mining industry. The mining industry-specialized Bochum archives is run as an organization in combination with a museum, which is called as German mine museum, so that it plays a role as a cultural center with the functions of exhibition and research. The three types of German business archives have their own functions but they are also closely related each other under the German Association of Business Archivists. They are sharing aims to preserve primary materials with historical values in the field of economy and also contribute to keeping the archives as a social resources by having feed back with the public, which leads the archives to be a center of information and research. The German case shows that business archives in a society should be preserved not only for the interest of the companies, but also for the utilities of social resources. It also shows us how business archives could be preserved as a social resource. It is expected that some studies which approach more deeply on this topic will be followed based on the considerations from the German case.

Dry reforming of Propane to Syngas over Ni-CeO2/γ-Al2O3 Catalysts in a Packed-bed Plasma Reactor (충전층 플라즈마 반응기에서 Ni-CeO2/γ-Al2O3 촉매를 이용한 프로페인-합성 가스 건식 개질)

  • Sultana, Lamia;Rahman, Md. Shahinur;Sudhakaran, M.S.P.;Hossain, Md. Mokter;Mok, Young Sun
    • Clean Technology
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    • v.25 no.1
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    • pp.81-90
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    • 2019
  • A dielectric barrier discharge (DBD) plasma reactor packed with $Ni-CeO_2/{\gamma}-Al_2O_3$ catalyst was used for the dry ($CO_2$) reforming of propane (DRP) to improve the production of syngas (a mixture of $H_2$ and CO) and the catalyst stability. The plasma-catalytic DRP was carried out with either thermally or plasma-reduced $Ni-CeO_2/{\gamma}-Al_2O_3$ catalyst at a $C_3H_8/CO_2$ ratio of 1/3 and a total feed gas flow rate of $300mL\;min^{-1}$. The catalytic activities associated with the DRP were evaluated in the range of $500{\sim}600^{\circ}C$. Following the calcination in ambient air, the ${\gamma}-Al_2O_3$ impregnated with the precursor solution ($Ni(NO_3)_2$ and $Ce(NO_3)_2$) was subjected to reduction in an $H_2/Ar$ atmosphere to prepare $Ni-CeO_2/{\gamma}-Al_2O_3$ catalyst. The characteristics of the catalysts were examined using X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectrometry (EDS), temperature programmed reduction ($H_2-TPR$), temperature programmed desorption ($H_2-TPD$, $CO_2-TPD$), temperature programmed oxidation (TPO), and Raman spectroscopy. The investigation revealed that the plasma-reduced $Ni-CeO_2/{\gamma}-Al_2O_3$ catalyst exhibited superior catalytic activity for the production of syngas, compared to the thermally reduced catalyst. Besides, the plasma-reduced $Ni-CeO_2/{\gamma}-Al_2O_3$ catalyst was found to show long-term catalytic stability with respect to coke resistance that is main concern regarding the DRP process.

The Tool to Design Sustainable Business Models: A Case Study for the Social Ventures (지속가능한 비즈니스모델 설계 도구: 소셜벤처 사례를 중심으로)

  • Park, JaeWhan;Jeon, Hyejin
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.14 no.1
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    • pp.187-198
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    • 2019
  • The purpose of this study is to seek ways of utilizing TLBMC by understanding business model of social ventures that are accompanied by social and environmental as well as economic missions. In order to achieve this, business models from economic, environmental and social perspectives will be analyzed, and we seek to enhance sustainability of social venture entrepreneurs. As the analysis tool, TLBMC(Triple Layered Business Model Canvas) expands upon the business model canvas that is widely utilized and recognizes economical terms. The TLBMC is proposed by Joyce, A., & Paquin, R. L.(2016) to help achieve a holistic view with horizontal and vertical associations. The study tries to overcome limitations of previous studies and observe a variety of economic, environmental, and social perspectives that social ventures should have with the TLBMC. As a result, it has the following implications; Firstly, creating separate social, environmental and economic business model canvas helps a business to have a holistic approach. Secondly, it was found that social venture characteristics of environmental and social perspectives were applied in practice. Lastly, we have established experience data on social venture business model. This study focuses on the opinions, the meanings and the subjective views of the participants. As a result, conclusions are drawn by the researchers ' assertions and has limitations as a research on case studies. However, this study will help people who are preparing or studying social ventures to have economic, environmental, and social perspectives. Also, redefinition of the direction and value of entrepreneurs operating social ventures, such as vision and mission, will help clarify the roles and responsibility of organizations. As a fundamental step for future empirical studies, this study could be the base for social venture business model studies.

Assessment of an Optimum Biochar Application Rate for Tomato(Solanum lycopersicum L.) Cultivation (토마토 재배를 위한 바이오차 최적시용 비율 평가)

  • Park, Do-Gyun;Hong, Seung-Gil;Jang, Eunsuk;Shin, Joung-Du
    • Journal of the Korea Organic Resources Recycling Association
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    • v.27 no.1
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    • pp.39-48
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    • 2019
  • Objective of this study was to evaluate an optimum biochar application rate and estimate the carbon sequestration based on the soil chemical properties and growth responses for biochar application during tomatoes cultivation. The treatments consisted of control as recommended application rates of fertilizers, 0.01%, 0.03%, 0.05%, and 0.07% of biochar application(w/w, biochar:soil). For effects of soil chemical properties, the $NO_3-N$contents in the soil were peaked at 9 days after transplanting. But there was not significant difference(p>0.05) among the treatments during cultivation periods. However, $NH_4-N$ contents in the biochar treatment were lower than the control until 14 days of transplanting. $P_2O_5$ contents in the biochar treatments were lower than that of the control until 19 days after transplanting except 0.01% of biochar application plot. $K_2O$ contents in soils treated with 0.01% and 0.03% of biochar were higher until 6 days after transplanting than that in the control. For N use efficiency of biochar application, it was observed that the 0.05% biochar application plot was highest among the treatments. The highest carbon sequestration was estimated at $2.83mg\;kg^{-1}$ for 0.03% of biochar application. However, it is considered that the optimum biochar application rate was 0.05% for tomato cultivation, considering the growth characteristics and yield components.

Development and Complementation of Evaluation Area and Content Elements in Electrical, Electronics and Communications Subject (중등교사 임용후보자선정경쟁시험 표시과목인 전기·전자·통신의 평가영역 및 내용요소 개발·보완 연구)

  • Song, Youngjik;Kang, Yoonkook;Cho, Hanwook;Gim, Seongdeuk;Lim, Seunggak;Lee, Hyuksoo
    • 대한공업교육학회지
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    • v.44 no.1
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    • pp.52-71
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    • 2019
  • The quality of school education is a key element for national education development. An important factor that determines the quality of school education is qualities of teachers who are in responsible for school education in the field. Therefore, it is necessary to hire competent teachers in the teacher appointment exam for the secondary school. This necessity is evident especially for vocational high schools and Meister high schools with the introduction of 2015-revised curriculum based on NCS that separates each three subjects, "Electrical, Electronics Communication" resulting in the change of question mechanism, which requires new designing of assessment and content area. So, this study analyzes curriculum in college of education for "Electrical", "Electronics", "Communication", 2015-revised curriculum based on NCS and the development of standards for teacher qualifications and assessment area and evaluation of teaching ability in the subjects of the teacher appointment exam, "Electrical, Electronics Communication" Engineering" in 2009. The assessment area and content elements of "Electrical", "Electronics", "Communication are extracted from the analyzed results and they are verified by experts' consultation and presented as follows; First, the assessment area and content elements of the "Electrical" subject were designed to evaluate the NCS - based 2015 revised curriculum by presenting the NCS learning module to the evaluation area and content element in the basic subject "Electrical and Electronics Practice". Second, the section of "Electronics" presented the assessment area and content elements applying the Electronic Circuit, basic subject of the NCS and it also added "Electromagnetics", which is the basic part of Electronics in the Application of Electromagnetic waves that could be applied to the assessment. Third, the assessment area and content elements of "Communication" consist of the communication-related practice that is based on "Electrical" and "Electronic", considering the characteristics of "Communication Engineering". In particular, "Electrical and Electronics practice" which adds network construction practice and communication-related practice makes it to be able to evaluate the communication-related practical education.

Forest Vegetation Structure in Maruguem(the Ridge Line) Area of Dakmokryeong to Daetjae, the Baekdudaegan (백두대간(닭목령-댓재 구간) 마루금 주변의 산림식생구조)

  • Song, Ju-Hyeon;Kwon, Jino;Yun, Chung-Weon
    • Korean Journal of Environment and Ecology
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    • v.33 no.1
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    • pp.28-51
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    • 2019
  • The purpose of this study was to analyze forest vegetation structure in Marugeum (the ridge line) area between Dakmokryeong and Daetjae in Baekdudaegan through vegetation classification, importance value, species diversity, and CCA using the data that were collected from 245 quadrates through Braun-Blanquet vegetation survey method from May to September in 2017. The results of the forest vegetation classification identified 8 vegetation units with Quercus mongolica community group at the highest level. Q. mongolica community group was classified into the Cornus controversa community, Buxus koreana community, Sasa borealis community, Abies nephrolepis community, and Q. mongolica typical community. C. controversa community was further classified into Quercus dentata group, Filipendula glaberrima group, Larix kaempferi group, and C. controversa typical group. The result of the important value analysis showed that Q. dentata had the highest importance value at 19.1% in vegetation unit 1 while Q. mongolica had the highest importance value at 22.7%, 38.3%, 25.6%, 41.3%, 27.9%, and 41.6% in vegetation unit 2, 4, 5, 6, 7, and 8, respectively, and L. kaempferi had the highest importance value at 27.6% in vegetation unit 3. As such, Q. mongolica species generally represented the communities of Marugeum (the ridge line) area of Dakmokryeong to Daetjae in Baekdudaegan. The results of species diversity showed that vegetation unit 1 and 2 were 3.305 and 3.236, respectively, which were relatively higher than other vegetation units. It was considered that this result was due to the influence of high emergence of present species. The results of the CCA analysis of the correlations between biotic environmental factors and vegetation types showed that vegetation unit 1 was mainly correlated with the megaphanerophyte ratio and vine plant ratio. In the correlations between abiotic environmental factors and vegetation types, vegetation unit 7 was significantly correlated with altitude. From the perspective of ecological management, vegetation unit 5 represented by B. koreana community was inhabited by a variety of plants due to the species composition and location environment due to the geological characteristics that are typical of limestone area. Vegetation unit 7 represented by A. nephrolepis community was typified as subalpine vegetation widely distributed by relict species and endemic species. We concluded that it is necessary to manage these vegetation units with an ecologically differentiated approach.

The Effect of CO2 Fixation for Microalgae based on CO2 Concentration and Flow Rate (이산화탄소 농도 및 유속에 따른 하천 내 미세조류의 이산화탄소 고정 효과)

  • Park, Hyomin;Lee, Sangdon
    • Journal of Wetlands Research
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    • v.20 no.4
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    • pp.363-369
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    • 2018
  • One of the recent environmental problems is climate change due to the increase of atmospheric $CO_2$, which causes ecological changes and various environmental problems. Therefore, various studies are being carried out to reduce $CO_2$ in the world in order to solve various environmental problems caused by increase of $CO_2$. The $CO_2$ reduction using microalgae is an environmentally friendly method by using photosynthesis reaction of microalgae. However, most studies using single species. There is no study on the $CO_2$ fixing efficiency of microalgae in natural rivers. Therefore, this study was to identify the microalgae in the Sum river and to analyze the growth characteristics of microalgae in the river to obtain optimal culture conditions. And the changes of biomass and chlorophyll-a of microalgae were analyzed according to $CO_2$ concentration and injection rate. The purpose of this study was to investigate the fixing efficiency of carbon dioxide in microalgae in natural rivers. Six kinds of dominant species were observed as a result of the identification of microalgae in Sum river(Ankistrodesmus falcatus, Scenedesmus intermedius, Selenodictyum sp., Xanthidium apiculatum var. laeve, Cosmarium pseudoquinarium, Dictyosphaerium pulchellum). All of these species were green algae. Biomass and chlorophyll-a increased with the increase of $CO_2$ concentration and biomass and chlorophyll-a increased faster flow rate at the same $CO_2$ concentration. Also, the quantity of $CO_2$ fixation on the microalgae tended to be higher when the flow rate of injected gas was faster. This study can be referred as being significant in the micro-algae in river. In addition, the optimal conditions for $CO_2$ fixation of microalgae in rivers and the quantification of the quantity of $CO_2$ fixation from microalgae in rivers can be used as basic data for future policy of $CO_2$ reduction.

A Study on the Decline of Provincial Government Office of Jeollabuk-do in Modern Era (근대기 전라북도 지방관아의 쇠퇴에 관한 연구)

  • Oh, Jun-young;Kim, Young-mo
    • Korean Journal of Heritage: History & Science
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    • v.48 no.1
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    • pp.24-43
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    • 2015
  • This study constitutes an inquiry into the decline of Government Office(官衙) facilities carried out intensively during modern era, focusing on provincial government offices of Jeollabuk-do. There have been several studies of changes in provincial government offices till now, but there have been few studies of government offices of the counties and prefectures(郡縣) during the period of the Japanese Resident-General of Korea and after the National Liberation, temporally and there have still been lacking studies on Jeollabuk-do, spatially. Thus, this study attempts to empirically prove the reasons and the time of the decline of provincial government offices in Jeollabuk-do and the characteristics in the process of decline focusing on modern era. As a result of the study, four factors: demolition, abolition, appropriation and disaster had the most decisive impacts on the decline of government office facilities. Demolition refers to the destruction of government office facilities, and abolition, to the decline and the discontinuation of the operation of the facilities. Appropriation refers to conversion to facilities to meet public functions, and disaster, damage from a typhoon or fire. These factors had already been started from the 1900s, and by the 1930s, most of the government office facilities came to lose their original looks and functions. In the meantime, there was an essential purpose in demolition, the most direct factor in the destruction of the government office facilities in terms of function: that is new construction of public facilities necessary for administration and rule. The existing government office facilities were appropriated, sometimes, but behind that, many cases of demolition of the government office facilities for the new construction of public facilities are found. The appropriation of the government office facilities is divided into educational, administrative, financial and security facilities, and generally, Gaeksa(客舍) and Dongheon(東軒) were used respectively as educational and administrative facilities while their attached facilities were used as financial and public order and security facilities in general. Especially, some government office facilities were utilized as distinctive facilities such as housing or hospital. In the process of appropriation, a lot of modification occurred inside and outside the government office facilities, due to which, the government office facilities gradually declined losing their traditional styles.