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Selecting Suitable Riparian Wildlife Passage Locations for Water Deer based on MaxEnt Model and Wildlife Crossing Analysis (MaxEnt 모형과 고라니의 이동행태를 고려한 수변지역 이동통로 적지선정)

  • Jeong, Seung Gyu;Lee, Hwa Su;Park, Jong Hoon;Lee, Dong Kun;Park, Chong Hwa;Seo, Chang Wan
    • Journal of Korean Society for Geospatial Information Science
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    • v.23 no.1
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    • pp.101-111
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    • 2015
  • Stream restoration projects have become threats to riparian ecosystem in Rep. of korea. Riparian wildlife becomes isolated and the animals are often experience difficulties in crossing riparian corridors. The purposes of this study is to select suitable wildlife passages for wild animals crossing riparian corridors. Maximum entropy model and snow tracking data on embankment in winter seasons were used to develop species distribution models to select suitable wildlife passages for water deer. The analysis suggests the following. Firstly, most significant factors for water deer's habitat in area nearby riparian area are shown to distance to water, age-class, land cover, slope, aspect, digital elevation model, tree density, and distance to road. For the riparian area, significant factors are shown to be land cover, size of riparian area, distance to tributary, and distance to built-up. Secondly, the suitable wildlife passages are recommended to reflect areas of high suitability with Maximum Entropy model in riparian areas and the surrounding areas and moving passages. The selected suitable areas are shown to be areas with low connectivity due to roads and vertical levee although typical habitats for water deer are forest, grassland, and farmland. In addition, the analysis of traces on snow suggests that the water deer make a detour around the artificial structures. In addition, the water deer are shown to make a detour around the fences of roads and embankment around farmland. Lastly, the water deer prefer habitats around riparian areas following tributaries. The method used in this study is expected to provide cost-efficient and functional analysis in selecting suitable areas.

Rapid Detection of Radioactive Strontium in Water Samples Using Laser-Induced Breakdown Spectroscopy (LIBS) (Laser-Induced Breakdown Spectroscopy (LIBS)를 이용한 방사성 스트론튬 오염물질에 대한 신속한 모니터링 기술)

  • Park, Jin-young;Kim, Hyun-a;Park, Kihong;Kim, Kyoung-woong
    • Economic and Environmental Geology
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    • v.50 no.5
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    • pp.341-352
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    • 2017
  • Along with Cs-137 (half-life: 30.17 years), Sr-90 (half-life: 28.8 years) is one of the most important environmental monitoring radioactive elements. Rapid and easy monitoring method for Sr-90 using Laser-Induced Breakdown Spectroscopy (LIBS) has been studied. Strontium belongs to a bivalent alkaline earth metal such as calcium and has similar electron arrangement and size. Due to these similar chemical properties, it can easily enter into the human body through the food chain via water, soil, and crops when leaked into the environment. In addition, it is immersed into the bone at the case of human influx and causes the toxicity for a long time (biological half-life: about 50 years). It is a very reductive and related with the specific reaction that makes wet analysis difficult. In particular, radioactive strontium should be monitored by nuclear power plants but it is very difficult to be analysed from high-cost problems as well as low accuracy of analysis due to complicated analysis procedures, expensive analysis equipment, and a pretreatment process of using massive chemicals. Therefore, we introduce the Laser-Induced Breakdown Spectroscopy (LIBS) analysis method that analyzes the elements in the sample using the inherent spectrum by generating plasma on the sample using pulse energy, and it can be analyzed in a few seconds without preprocessing. A variety of analytical plates for samples were developed to improve the analytical sensitivity by optimizing the laser, wavelength, and time resolution. This can be effectively applied to real-time monitoring of radioactive wastewater discharged from a nuclear power plant, and furthermore, it can be applied as an emergency monitoring means such as possible future accidents at a nuclear power plants.

Adsorption Characteristics of Heavy Metal Ions onto Chemically Modified Rice Husk and Sawdust from Aqueous Solutions (화학적으로 개질된 왕겨 및 톱밥(미송, 참나무, 포플러)의 중금속 흡착특성)

  • Lee, Hyeon-Yong;Jeon, Choong;Lim, Kyoung-Jae;Hong, Ki-Chan;Lim, Jung-Eun;Choi, Bong-Su;Kim, Nam-Won;Yang, Jae-E;Ok, Yong-Sik
    • Korean Journal of Environmental Agriculture
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    • v.28 no.2
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    • pp.158-164
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    • 2009
  • Biosorption uses adsorbents derived from non-living biomass and removes toxic metals from industrial wastewater. The objective of this research was to evaluate the potential of low cost biosorbents to remove heavy metal ions (Cd, Cu, Pb and Zn) from aqueous solutions using chemically modified rice husk and saw dust (Pseudotsuga menziesi, Quercus, Populus). Batch-type adsorption experiments were carried out using rice husk and saw dust treated with NaOH and/or tartaric acid in artificial wastewater 100 mg metal/L). The experimental results showed that the adsorption specificity of each biosorbent was Pb > Cu > Cd > Zn irrespective of the types of biosorbents. The adsorption capacity of Pb and Cu onto NaOH-treated sawdust was increased 2${\sim}$3 times compared to the untreated one. In addition, the tartaric acid treatment increased the adsorption capacity of rice husk for Zn and Cd approximately 5${\sim}$10 fold compared to the untreated one. Surface conditions and changes in functional groups by chemical modification of each biosorbent were confirmed by SEM and FT-IR. Overall, the results show that chemical modification increases the metal removal capacity of rice bran and sawdust.

Studies on Utilization Survey and Forage Quality of Phragmites communis and Miscanthus sinensis as Native Grasses in Paju and Ansan District, 2010 (2010 파주, 안산지역 갈대, 억새 등 야초류의 이용실태와 사료가치 평가)

  • Seo, Sung;Kim, Won-Ho;Jung, Min-Woong;Park, Hyung-Soo;Shim, Jae-Jin;Park, Jin-Gil;Sung, Ha-Guyn;Kim, Jong-Duk;Lee, Joung-Kyong
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.31 no.2
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    • pp.151-158
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    • 2011
  • This study was carried out in 2010 to investigate the utilization and nutritive value of native grasses, such as Phragmites communis and Miscanthus sinensis which might reduce the cost of feeding domestic cattle. The regions within the Civilian Control Line in Paju and Sihwa region in Ansan were surveyed. In Paju, the yearly silage production was 900 MT harvested from 90 ha (10 MT/ha). About 30~50% of these were sold out at the marketing price of 52,000~55,000 Won per roll (130~137.5 Won/kg). Regrown Miscanthus sinensis of 70 cm in length contained 9.6% of crude protein (CP), 82.4 of relative feed value (RFV), and 67.7% of in vitro dry matter digestibility (IVDMD). Regrown Phragmites communis of 70 cm in length contained 13.8% of CP, 84.3 of RFV, and 67.9% of IVDMD. As harvesting was delayed, the quality was decreased dramatically. In Ansan region, Phragmites communis plantation covers 100 ha. The silage production was 550 MT from the area of 50 ha (11 MT/ha) in 2009. And the marketing price was 50,000 Won per roll. But in 2010 only a small amount of grasses could have been baled due to frequent and much rainfall from spring to summer season. However, the good forage quality was observed from regrown Phragmites communis of 80 cm in length, 12.9% CP, 99.8 RFV and 66.6% IVDMD, while that of late matured grasses was very low, 2.2% CP, 52.9 RFV and 36.4% IVDMD, greatly lower than forage quality of rice straw. The quality of grasses at bloom stage of 150 cm in length was similar to that of rice straw, showing 4.5% CP, 59.9 RFV and 42.2% IVDMD. In conclusion, the overall quality of most native grasses in this survey were very poor. Therefore, we recommend that Phragmites communis and Miscanthus sinensis should be harvested during June or July to obtain better forage quality which is richer in forage values than rice straw. Production of high quality forage crops was also desirable for self sufficiency of forage.

Current Status and Prospects of Various Methods used for Screening Probiotic Microorganisms (Probiotic 미생물 검사에 사용되는 다양한 방법들에 대한 현황과 향후 전망)

  • Kim, Dong-Hyeon;Kim, Hong-Seok;Jeong, Dana;Chon, Jung-Whan;Kim, Hyunsook;Kim, Young-Ji;Kang, Il-Byung;Lee, Soo-Kyung;Song, Kwang-Young;Park, Jin-Hyeong;Chang, Ho-Seok;Seo, Kun-Ho
    • Journal of Dairy Science and Biotechnology
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    • v.34 no.4
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    • pp.203-216
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    • 2016
  • Probiotic microorganisms are thought to provide health benefits when consumed. In 2001, the World Health Organization defined probiotics as "live microorganisms which confer a health benefit on the host, when administered in adequate amounts." Three methods for screening potential probiotics have currently widely available. (1) In vitro assays of potential probiotics are preferred because of their simplicity and low cost. (2) The use of in vivo approaches for exploring various potential probiotics reflects the enormous diversity in biological models with various complex mechanisms. (3) Potential probiotics have been analyzed using several genetic and omics technologies to identify gene expression or protein production patterns under various conditions. However, there is no ideal procedure for selecting potential probiotics than testing cadidate strains on the target population. Hence, in this review, we provide an overview of the different methodologies used to identify new probiotic strains. Furthermore, we describe futre perspectives for the use of in vitro, in vivo and omics in probiotic research.

Effect of Coolant on PEMFC Performance in Low Humidification Condition (저가습 조건에서 냉각 유체의 고분자전해질 연료전지에 대한 영향)

  • Lee, Hung-Joo;Song, Hyun-Do;Kwon, Jun-Taek;Kim, Jun-Bom
    • Journal of the Korean Electrochemical Society
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    • v.10 no.1
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    • pp.25-30
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    • 2007
  • Proton exchange membrane fuel cell(PEMFC) performance could be affected by various factors such as cell temperature, total pressure, partial pressure of reactants and relative humidity. Hydrogen ion is combined with water to form hydronium ion [$H_3O^+$] and pass through membrane resulting electricity generation. Cooling system is needed to remove heat and other uses on large scale fuel cell. In case that collant conductivity is increased, fuel cell performance could be decreased because produced electricity could be leaked through coolant. In this study, triple distilled water(TDW) and antifreeze solution containing ethylene glycol was used to observe resistance change. Resistance of TDW was taken 28 days to reach preset value, and effect on fuel cell operation was not observed. Resistance of antifreeze solution was not reached to preset value up to 48 days, but performance failure occurred presumably caused by bipolar plate junction resulting stoppage resistance experiment. Generally PEMFC humidification is performed near-saturated operating conditions at various temperatures and pressures, but non-humidifying condition could be applied in small scale fuel cell to improve efficiency and reduce system cost. However, it was difficult to operate large scale fuel cell without humidifying, especially higher than $50{\sim}60^{\circ}C$. In case of small flux such as 0.78 L/min, temperature difference between inlet and outlet was occurred larger than other cases resulting performance decrease. Non-humidifying performance experiments were done at various cell temperature. When both of anode and cathode humidification were removed, cell performance was strongly depended on cell operating temperature.

Trends of mushroom science and mushroom industry (버섯과학과 버섯산업의 동향)

  • Yoo, Young-Bok;Kong, Won-Sik;Oh, Se-Jong;Cheong, Jong-Chun;Jang, Kab-Yeul;Jhune, Chang-Sung
    • Journal of Mushroom
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    • v.3 no.1
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    • pp.1-23
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    • 2005
  • World production of mushrooms has been increasing 10-20% every year. Recently, Pleurotus eryngii and P. nebrodensis are very popular as new mushroom species for cultivation. Two kinds of mushrooms, Gumji (Ganoderma) and Soji, were described in old book of Samguksagi (History of the three kingdoms; 1145) in Koryo-dynasty. Many kinds of mushrooms were also described in more than 16 kinds of old books during Chosun-dynasty in Korea. One hundred and sixty commercial strains of 25 species in mushrooms were distributed to cultivators. By the way, only 8 varieties of them have registered variety protection. Mushroom industry as important export products developed from 1960 to 1980. Production of mushrooms as food was 181,828 metric tons valued at 800 billion Korean won in 2003. Isolated and identified substances from mushrooms are promising antifungal, antiinflammatory, antitumor, antiviral (anti-HIV), antibacterial & antiparasitic, antidiabetic, immunomodulating, kidney tonic, hepatoprotective, nerve tonic, and sexual potentiator. These substances can also be used for blood pressure regulation and effective against cardiovascular disorders, hypocholesterolemia & hyperlipidemia, and chronicbronchitis. Mushroom products including pharmaceuticals, tonics, healthy beverages, functional biotransformants, and processed foods have also became available on the markets. Compost and feed can likewise be made from mushroom substrates after harvest. The mushroom industry is already one of the fastest growing investment sectors in Korea. By the way, there is a need to strain improvement for variety protection, advanced cultivation technology at low cost for growers, and control of demand and supply for marketing in order to more upgrade development of mushroom industry in the future.

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A Study on the Field Data Applicability of Seismic Data Processing using Open-source Software (Madagascar) (오픈-소스 자료처리 기술개발 소프트웨어(Madagascar)를 이용한 탄성파 현장자료 전산처리 적용성 연구)

  • Son, Woohyun;Kim, Byoung-yeop
    • Geophysics and Geophysical Exploration
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    • v.21 no.3
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    • pp.171-182
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    • 2018
  • We performed the seismic field data processing using an open-source software (Madagascar) to verify if it is applicable to processing of field data, which has low signal-to-noise ratio and high uncertainties in velocities. The Madagascar, based on Python, is usually supposed to be better in the development of processing technologies due to its capabilities of multidimensional data analysis and reproducibility. However, this open-source software has not been widely used so far for field data processing because of complicated interfaces and data structure system. To verify the effectiveness of the Madagascar software on field data, we applied it to a typical seismic data processing flow including data loading, geometry build-up, F-K filter, predictive deconvolution, velocity analysis, normal moveout correction, stack, and migration. The field data for the test were acquired in Gunsan Basin, Yellow Sea using a streamer consisting of 480 channels and 4 arrays of air-guns. The results at all processing step are compared with those processed with Landmark's ProMAX (SeisSpace R5000) which is a commercial processing software. Madagascar shows relatively high efficiencies in data IO and management as well as reproducibility. Additionally, it shows quick and exact calculations in some automated procedures such as stacking velocity analysis. There were no remarkable differences in the results after applying the signal enhancement flows of both software. For the deeper part of the substructure image, however, the commercial software shows better results than the open-source software. This is simply because the commercial software has various flows for de-multiple and provides interactive processing environments for delicate processing works compared to Madagascar. Considering that many researchers around the world are developing various data processing algorithms for Madagascar, we can expect that the open-source software such as Madagascar can be widely used for commercial-level processing with the strength of expandability, cost effectiveness and reproducibility.

Myanmar's Macroeconomic changes and its Implications for the Invest of Korean Enterprises (미얀마 통상환경의 변화와 한국기업의 투자 및 진출에 관한 시사점)

  • Jung, Sung-Hoon;Kwon, O-Yoon
    • International Commerce and Information Review
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    • v.13 no.4
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    • pp.177-201
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    • 2011
  • Myanmar had fallen behind other southeast asian nations since Burmese way to Socialism settled down. However, historically second election in Myanmar hold in 2011 and dramatic changes in areas such as Special Economic Zone announcement, the very huge inflows of foreign direct investment in a year of 2009, the infrastructure building projects, a permit of the right to strike for Labour Organization in Myanmar etc. Particularly, Foreign investments and trade with neighbouring countries are actively growing and also with Korea. But investments of Korea in Myanmar relatively are not diversity, with limited sectors such as mining and sewing manufacturing. In this point of view, this paper is trying to make implications for strategies of entry and investments of Korea in Myanmar by using previous papers related to Myanmar economies, trade and foreign investments with updated statistical data. The implications for Korea is that recently Myanmar economy is in its early stages of development. Although it can occur huge demand of railway, road, communications and constructions related to social infrastructures essentially needed for development of a country, these sectors relatively need huge investments. On the other hands, textile and sewing industry relatively need smaller investments in which investors can utilize low labour cost and a position for export to third countries. But those firms which set up for those purpose in Myanmar might have trouble creating domestic markets in future. Moreover, due to demand which occur in the early stage of growth in Myanmar, trade volume tend to increase and trading is also possible to invest but Myanmar still have lots of problems with infrastructure such as road and logistics and we need to make pre-survey for the costs and benefits of our products Finally, Myanmar government is trying to promote and encourage some of industries such as export-oriented industry, import substitution industry and labour-intensive industry. It can also means they will accumulate capital which can be sources for Myanmar economic growth.

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Analysis of Industrial Linkage Effects for Farm Land Base Development Project -With respect to the Hwangrak Benefited Area with Reservoir - (농업생산기반 정비사업의 산업연관효과분석 -황락 저수지지구를 중심으로-)

  • Lim, Jae Hwan;Han, Seok Ho
    • Korean Journal of Agricultural Science
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    • v.26 no.2
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    • pp.77-93
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    • 1999
  • This study is aiming at identifying the foreward and backward lingkage effects of the farm land base development project. Korean Government has continuously carried out farmland base development projets including the integrated agricultural development projects. large and medium scale irrigation projects and the comprehensive development of the four big river basin including tidal land reclamation and estuary dam construction for the all weather farming since 1962. the starting year of the five year economic development plans. Consequently the irrigation rate of paddy fields in Korea reached to 75% in 1998 and to escalate the irrigation rate, the Government had procured heavy investment fund from IBRD. IMF and OECF etc. To cope with the agricultural problems like trade liberalization in accordance with WTO policy, the government has tried to solve such problems as new farmland base development policy, preservation of the farmland and expansion of farmland to meet self-sufficiency of foods in the future. Especially, farmland base development projects have been challanged to environmental and ecological problems in evaluating economic benefits and costs where the value of non-market goods have not been included in those. Up to data, in evaluating benefits and costs of the projects, farmland base development projects have been confined to direct incremental value of farm products and it's related costs. Therefore the projects'efficiency as a decision making criteria has shown the low level of economic efficiencies. In estimating economic efficiencies including Leontiefs input-output analysis of the projects could not be founded in Korea at present. Accordingly this study is aimed at achieving and identifying the following objectives. (1) To identify the problems related to the financial supports of the Government in implementing the proposed projects. (2) To estimated backward and foreward linkage effects of the proposed project from the view point of national economy as a whole. To achieve the objectives, Hwangrak benefited area with reservoir which is located in Seosan-haemi Disticts, Chungnam Province were selected as a case study. The main results of the study are summarized as follows : a. The present value of investment and O & M cost were amounted to 3,510million won and the present value of the value added in related industries was estimated at 5.913million won for the period of economic life of 70 years. b. The total discounted value of farm products in the concerned industries derived by the project was estimated at 10,495million won and the foreward and backward linkage effects of the project were amounted to 6,760 and 5,126million won respectively. c. The total number of employment opportunities derived from the related industries for the period of project life were 3,136 man/year. d. Farmland base development projects were showed that the backward linkage effects estimated by index of the sensitivity dispersion were larger than the forward linkage effect estimated by index of the power of dispersion. On the other hand, the forward linkage effect of rice production value during project life was larger than the backward linkage effect e. The rate of creation of new job opportunity by means of implementing civil engineering works were shown high in itself rather than any other fields. and the linkage effects of production of the project investment were mainly derived from the metal and non-metal fields. f. According to the industrial linkage effect analysis, farmland base development projects were identified economically feasible from the view point of national economy as a whole even though the economic efficiencies of the project was outstandingly decreased owing to delaying construction period and increasing project costs.

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