• Title/Summary/Keyword: 추정법

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Analysis of Hydraulic Gradient at Coastal Aquifers in Eastern Part of Jeju Island (제주도 동부지역 해안대수층의 조석에 의한 수리경사 변화 연구)

  • Kim, Kue-Young;Shim, Byoung-Ohan;Park, Ki-Hwa;Kim, Tae-Hee;Seong, Hyeon-Jeong;Park, Yun-Seok;Koh, Gi-Won;Woo, Nam-Chil
    • Economic and Environmental Geology
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    • v.38 no.1
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    • pp.79-89
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    • 2005
  • Groundwater level changes in coastal aquifers occur due to oceanic tides, where the properties of oceanic tides can be applied to estimate hyadraulic parameters. Hydraulic parameters of coastal aquifers located in eastern part of Jeju island were estimated using the tidal response technique. Groundwater level data from a saltwater intrusion monitoring well system was used which showed tidal effects from 3 to 5 km. The hydraulic gradient was assessed by utilizing the filtering method from 71 consecutive hourly water-level observations. Calculated hydraulic diffusivity ranged from 2.94${\times}10^7m^2d^{-1}$ to 4.36${\times}10^7m^2d^{-1}$ . The hydraulic gradient of the coastal aquifer area was found to be ~$10^{-4}$, whereas the gradient of the area between wells Handong-1 and 2 was found to be ~$10^{-6}$, which is very low comparatively. Analysis of groundwater monitoring data showed that groundwater levels are periodically higher near coastal areas compared to that of inner land areas due to oceanic tide influences. When assessing groundwater flow direction in coastal aquifers it is important to consider tidal fluctuation.

A Value Evaluation Research of the Old-growth and Giant Tree - Focus on Gyeongju Gyerim's Zelkova Serrata - (노거수의 가치 평가 연구 - 경주 계림숲 느티나무를 대상으로 -)

  • Son, Hee-Jun;Xia, Tian-Tian;Kim, Young-Hun;Kang, Tai-Ho
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.34 no.4
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    • pp.51-56
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    • 2016
  • Old-growth and giant tree is a nonrenewable resource with great value. The purpose of this study is to provide scientific and reasonable evaluations for the preservation and management of the old-growth and giant tree. Until now the research of old-growth and giant tree's value evaluation and authoritative index is so insufficient and imperfection. Combining with the particularity of the old-growth and giant tree, this study analyzed the main value factors of the old-growth and giant tree and objectively selected the evaluation indicators. According to the actual situation value appraisal model of the old-growth and giant tree was builded. The main value factors can be divided into economic value, cultural history, growing place, tree state, tree form, tree vigor, protection level, growth environment, tree species, tree canopy, and so on. The evaluate indicators can be selected and the indicators' weight can be calculate using analytic hierarchy process methods(AHP). Based on economic value and indicators' weight, tree's total value can be revealed. After calculation and analysis, Gyeongju Gyerim Zelkova serrata's value evaluation results is 491,503,300 won. The research results of this study can provide scientific basis and reference to the old-growth and giant trees' value appraisal and loss compensation, and arouse people's environmental awareness.

Study on Inhibition of Platelet Aggregation of Bioactive constituents from Paeonia lactiflora (작약의 혈소판 응집억제작용에 관한 연구)

  • 서범석;박관혁;손동주;박영현;장성근
    • Proceedings of the KAIS Fall Conference
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    • 2003.06a
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    • pp.320-321
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    • 2003
  • 최근 천연물을 중심으로 한 학문이 발전하면서 천연물이 가지는 생리활성 물질에 대한 관심이 중대되고 있다. 또한 인공합성품의 일부가 안정성의 문제가 제기되면서 천연물의 이용분야는 더욱 확대되고 있다. 급속한 경제발전과 생활수준의 향상으로 식생활을 포함한 생활방식의 다양화로 인하여 과거 감염 위주의 질병이 감소하고 선진국형의 만성퇴행성 질환이 증가하는 추세이다. 혈소판은 혈전증(thrombosis)과 지혈증(haemstasis)에서 중요한 역할을 담당하고 있는 인자로서 현관 내 병적 이상으로 인한 과도한 혈전의 생성은 뇌 -심혈관계 질환의 중요한 유발인자로 작용하므로 뇌ㆍ심혈관계 질환이나 항고지혈증을 연구하는데 유용하게 이용되고 있다. 본 연구에서는 토끼 혈액에서 분리한 세정 혈소판 부유액을 이용하여 작약 MeOH 추출물에서 분리한 천연생리활성물질들을 대상으로 혈소판 응집억제활성에 대하여 연구하였다. 작약 MeOH 추출물의 혈소판 응집억제활성 측정에서 강한 혈소판 응집억제활성 작용을 보였다. 따라서 작약 MeOH 추출물을 크로마토그라피법을 이용하여 분리하였고, NMR을 이용한 분광학적 방법으로 지금까지의 분리한 자료와 비교ㆍ분석하였다. Monoterpene glycoside 계열의 성분들인 15개의 compound와 다수의 fraction들을 HPLC를 이용하여 분리하였으며, collagen으로 유도된 혈소판 응집억제활성측정 방법에서 뛰어난 응집억제활성을 보였다. 표준물질을 이용한 HPLC 분석과 ¹H-NMR 관련 자료의 검색을 통하여 최종적으로 compound 1b가 benzoyloxy-paeoniflorin(2.6%). compound 1d가 paeond(1.3%), compound 2c가 albiflorin(3.2%), compound 2e가 paeoniflorin(33.6%)임을 확인할 수 있었다. Compound 3a의 분석결과 benzoyloxypaeoniflorin과 구조적 유사성은 있으나 동일한 구조식으로 확인할 수 없었다. 그러나 collagen에서 응집억제활성이 90% 이상으로 뛰어난 활성을 나타내므로 benzoyloxypaeoniflorin과 유사한 구조에서 benzoyl group이 다른 작용기로 치환되었거나 R₁ group이 다른 작용기로 치환된 형태로 추측하였다. Benzoyloxypaeoniflorin은 collagen>thrombin>U46616>A.A(arachidonic acid)>PAF의 순으로 활성을 보였다. 이는 paeoniflorin의 glycoside 5-carbon위치에 위치한 OH기 대신에 benzoyl기로 치환된 benzoyl 기가 혈소판 억제 산물로 작용한 것으로 추측했다. Paeoniflorin.은 U46619>thrombin>collagen>A.A>PAF순으로 억제를 보였다. Paeoniflorin이 collagen보다 thrombin에서 강한 억제를 보이는 것으로 Ca/sup 2+/ chelate를 형성함으로 인해 calciu 대사를 저해하는 것으로 추축했다. Compound 3a는 U46619>collagen>A.A>thrombin>PAF순으로 억제율을 보이므로 이 화합물은 paeoniflorin의 benzoyl기에 OH기가 다른 치환기로 바뀌거나 paeoniflorin의 glycoside 5-carbon 위치의 OH기 대신에 다른 작용기로 치환된 것으로 추정하였다. 이러한 결과로 작약의 주성분인 paeoniflorin과 유사한 구조를 가진 다른 monoterpene glycoside 계열의 화합물들과 비교 분석하고 구조를 화인하고 이들 성분이 어떻게 혈소판 응집억제활성에 작용하는지를 연구하였다.

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A Basic Study on Non-aqueous Electrolysis of Neodymium for Room-temperature Metallurgy (상온제련을 위한 네오디뮴의 비수계 전해 기초연구)

  • Park, Jesik;Lee, Churl Kyoung
    • Resources Recycling
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    • v.27 no.4
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    • pp.29-35
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    • 2018
  • In this study, the electrochemical redox behavior of neodymium in non-aqueous electrolytes was investigated to confirm the possibility of neodymium metallurgy at room temperature. The non-aqueous electrolytes include ionic liquids such as $[C_4mim]PF_6$, $[C_4mim]Cl$, and $[P_{66614}]PF_6$, ethanol which are highly soluble in neodymium salts, and mixed electrolytes based on carbonate with highly electrochemical stability. The electrochemical redox properties of neodymium were better than those of other electrolytes in the case of the mixed electrolyte based on ethylene carbonate (EC)/di-ethylene carbonate (DEC). Ethanol was added to improve the physical properties of the mixed electrolyte. Thorough the analysis about ionic conductivity of EC/DEC ratio, ethanol content and $NdCl_3$ concentration, the best electrolyte composition was 50 vol% content of ethanol and 0.5 M of $NdCl_3$. Using cyclic voltametry and linear sweep voltametry, a current peak estimated at -3.8 V (vs. Pt-QRE) was observed as a limiting current of neodymium reduction. Potentiostatic electrolysis for 18 hours at room temperature at -6 V (vs. Pt-QRE) confirmed that metallic neodymium was electrodeposited.

Investigating the Impact of Corporate Social Responsibility on Firm's Short- and Long-Term Performance with Online Text Analytics (온라인 텍스트 분석을 통해 추정한 기업의 사회적책임 성과가 기업의 단기적 장기적 성과에 미치는 영향 분석)

  • Lee, Heesung;Jin, Yunseon;Kwon, Ohbyung
    • Journal of Intelligence and Information Systems
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    • v.22 no.2
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    • pp.13-31
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    • 2016
  • Despite expectations of short- or long-term positive effects of corporate social responsibility (CSR) on firm performance, the results of existing research into this relationship are inconsistent partly due to lack of clarity about subordinate CSR concepts. In this study, keywords related to CSR concepts are extracted from atypical sources, such as newspapers, using text mining techniques to examine the relationship between CSR and firm performance. The analysis is based on data from the New York Times, a major news publication, and Google Scholar. We used text analytics to process unstructured data collected from open online documents to explore the effects of CSR on short- and long-term firm performance. The results suggest that the CSR index computed using the proposed text - online media - analytics predicts long-term performance very well compared to short-term performance in the absence of any internal firm reports or CSR institute reports. Our study demonstrates the text analytics are useful for evaluating CSR performance with respect to convenience and cost effectiveness.

A Calculation of Compression Index of the South Coast Soft Clay Utilizing Field Measurement (계측자료를 활용한 남해안 연약 점성토의 압축지수 산정)

  • Lee, Changouk;Park, Choonsik;Kwon, Hyeonjin;Kim, Jonghwan
    • Journal of the Korean GEO-environmental Society
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    • v.16 no.6
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    • pp.23-30
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    • 2015
  • This study analyzed degree of disturbance, using specimens by laboratory test with large block specimens and piston samplers collected from the Korea's two typical soft ground districts: South coast Gwangyang and Yangsan. To assess the characteristics of compression index of laboratory test incurred by disturbance, the compression index of laboratory test was compared with the back analysis compression index resulting from the analysis of the measured settlement. The analysis of specimen disturbance of the laboratory test results with the piston specimens of the two districts found that the qualities of most specimens were poor and the settlement predicted by the laboratory test compression index was underestimated. The analysis of test material taken from nearby areas proved that the disturbance degrees of large block specimens were lower than that of the piston specimens. The hyperbolic method, Hoshino method, Asaoka method, and ${\sqrt{S}}$ method, all of which are predictive methods using measured settlement, were employed to reach a conclusion that reliabilities of each predictive method except predictive material of a few points were the same. To compensate the disturbance effects on compression index of the piston specimens, we suggested a new modification formula that estimates compression index of piston specimens, using Schmertmann's corrected compression index, and back analysis compression index from the analysis of predictive settlement.

An Uncertainty Analysis of Calculating Life Cycle Maintenance and Energy Costs for Technical Proposals (기술제안입찰을 위한 유지관리 및 에너지 비용 산출방식의 불확실성 분석)

  • Chung, Sung Young;Kim, Sean Hay
    • Korean Journal of Construction Engineering and Management
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    • v.19 no.5
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    • pp.3-9
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    • 2018
  • Although Life Cycle Cost (LCC) must be evaluated by experts, sometimes it may not allow a sufficient time for even the experienced LCC expert to make rational decisions. Therefore, it often ends with relatively comparing the final numbers. We have broken down 110 technical proposals that are actually bade and accepted for large construction projects, and then have analyzed the uncertainty of Maintenance and Energy (M&E) cost during building life cycle, which turns out be the most volatile factor in uncertainty of LCC. Also we suggest "Value Engineering Index (VEI)" - the reduced M&E cost that is normalized by the reduced first cost. It is analyzed that the most uncertain factors of the M&E cost include repair and replacement term differing from each project, duplicated repair and replacement, non-standard repair items, and site-specific energy cost. Eventually we propose a VEI population with a mean of 1.38 and a standard deviation of 1.19, which is obtained by individually and exclusively applying the uncertain factors of the M&E cost to the 35 standard sample of technical proposals. The LCC evaluators may be able to use the VEI population as the benchmark to select the technical proposal with the most reasonable LCC among many others in two suggested manners; the one is to deterministically calculate the probability of single VEIs, and the other is to stochastically calculate the probability of the VEIs where uncertainty is quantified.

Community Classification and Successional Trends in the Natural Forest of Baekdudaegan in Gangwon Province -Focused on Hyangrobong, Odaesan, Seokbyeongsan, Dutasan, Deokhangsan and Hambaeksan- (강원지역 백두대간 천연림의 군집분류 및 천이경향 -향로봉, 오대산, 석병산, 두타산, 덕항산, 함백산 등을 중심으로-)

  • Hwang, Kwang-Mo;Lee, Jeong-Min;Kim, Ji-Hong
    • Journal of agriculture & life science
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    • v.46 no.4
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    • pp.41-55
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    • 2012
  • On the basis of vegetation data collected by point-centered quarter method in analysis in Baekdudaegan of Gangwon province in the area of Hyangrobong, Odaesan, Seokbyeongsan, Dutasan, Deokhangsan and Hambaeksan, the study was carried out to classify forest communities and to evaluate the successional trends. The classification method of cluster analysis was used to make various disordered forests into several common groups for 1,004 sample points all together. By clustering the forests in the six study areas were classified into 28 forest communities, which were subjected to aggregate 8 representative forest communities on the count of species composition and species diversity. They were Mesophytic mixed forest community, others deciduous forest community, Quercus mongolica (dominant) community, Q. mongolica (pure) community, Pinus densiflora - Q. mongolica community, P. densiflora community, Betula ermanii community and Q. mongolica - Pinus koraiensis community. The ecological outlook from the result indicated that P. densiflora community and P. densiflora - Q. mongolica community, which were located in Seokbyeongsan, Dutasan and Deokhangsan around 1,000m above the sea level showed lower species diversity index. On the contrary Mesophytic mixed forest community, others deciduous forest community which was located in Hyangrobong, Odaesan and Hambaeksan mostly in protected area and national park around 1,500m above the sea level displayed higher species diversity index. As the composition ratio of Q. mongolica within a certain community was decreased, the species diversity was generally increased, assumed that abundance of Q. mongolica might be negatively associated with species diversity in the national deciduous forest.

SAR Image Impulse Response Analysis in Real Clutter Background (실제 클러터 배경에서 SAR 영상 임펄스 응답 특성 분석)

  • Jung, Chul-Ho;Jung, Jae-Hoon;Oh, Tae-Bong;Kwang, Young-Kil
    • Korean Journal of Remote Sensing
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    • v.24 no.2
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    • pp.99-106
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    • 2008
  • A synthetic aperture radar (SAR) system is of great interest in many fields of civil and military applications because of all-weather and luminance free imaging capability. SAR image quality parameters such as spatial resolution, peak to sidelobe ratio (PSLR), and integrated sidelobe ratio (ISLR) can be normally estimated by modeling of impulse response function (IRF) which is obtained from various system design parameters such as altitude, operational frequency, PRF, etc. In modeling of IRF, however, background clutter environment surrounding the IRF is generally neglected. In this paper, analysis method for SAR mage quality is proposed in the real background clutter environment. First of all, SAR raw data of a point scatterer is generated based on various system parameters. Secondly, the generated raw data can be focused to ideal IRF by range Doppler algorithm (RDA). Finally, background clutter obtained from image of currently operating SAR system is applied to IRF. In addition, image quality is precisely analyzed by zooming and interpolation method for effective extraction of IRF, and then the effect of proposed methodology is presented with several simulation results under the assumption of estimation error of Doppler rate.

Business Performance Indicators and Determinants Analysis of Small and Medium Sized Shipping Logistics Companies in Korea - Using 2015 Economic Census Data (국내 중소 해운물류기업의 경영성과지표 산정 및 결정요인 분석 - 2015년 경제총조사 자료를 이용하여)

  • Han, Sang-Yong;Lee, Joo-Suk
    • Journal of Korea Port Economic Association
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    • v.34 no.4
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    • pp.53-68
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    • 2018
  • This paper analyzes comparatively business performance indicators and determinants of small and medium sized shipping logistics companies in Korea, using 2015 economic census data. For this purpose, this study estimates various business performance indicators according to 2015 small and medium sized companies classification standards, including operating income to sales and gross value-added to sales. In addition, this study analyzes determinants of business performance using generalized least squares models. The results indicate that average sales, operating income and value-added, sales and operating income per worker, operating income to sales, and material cost to sales of large sized companies are higher than those of small and medium sized companies. The business performance indicators differ by industry and size. Moreover, the determinants of business performance are analyzed in terms of the unemployment rate (-), number of employees (-), sales (+), labor cost ratio (+), and labor cost per employee (-) and the impacts of the individual explanatory variables based on elasticity are different. Finally, this quantitative information could be used to improve the business performance of domestic shipping logistics companies.