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Prediction of Soil Erosion from Agricultural Uplands under Precipitation Change Scenarios (우리나라 강우량 변화 시나리오에 따른 밭토양의 토양 유실량 변화 예측)

  • Kim, Min-Kyeong;Hur, Seong-Oh;Kwon, Soon-Ik;Jung, Goo-Bok;Sonn, Yeon-Kyu;Ha, Sang-Keun;Lee, Deog-Bae
    • Korean Journal of Soil Science and Fertilizer
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    • v.43 no.6
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    • pp.789-792
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    • 2010
  • Major impacts of climate change expert that soil erosion rate may increase during the $21^{st}$ century. This study was conducted to assess the potential impacts of climate change on soil erosion by water in Korea. The soil loss was estimated for regions with the potential risk of soil erosion on a national scale. For computation, Universal Soil Loss Equation (USLE) with rainfall and runoff erosivity factors (R), cover management factors (C), support practice factors (P) and revised USLE with soil erodibility factors (K) and topographic factors (LS) were used. RUSLE, the revised version of USLE, was modified for Korean conditions and re-evaluate to estimate the national-scale of soil loss based on the digital soil maps for Korea. The change of precipitation for 2010 to 2090s were predicted under A1B scenarios made by National Institute of Meteorological Research in Korea. Future soil loss was predicted based on a change of R factor. As results, the predicted precipitations were increased by 6.7% for 2010 to 2030s, 9.5% for 2040 to 2060s and 190% for 2070 to 2090s, respectively. The total soil loss from uplands in 2005 was estimated approximately $28{\times}10^6$ ton. Total soil losses were estimated as $31{\times}10^6$ ton in 2010 to 2030s, $31{\times}10^6$ ton in 2040 to 2060s and $33{\times}10^6$ ton in 2070 to 2090s, respectively. As precipitation increased by 17% in the end of $21^{st}$ century, the total soil loss was increased by 12.9%. Overall, these results emphasize the significance of precipitation. However, it should be noted that when precipitation becomes insignificant, the results may turn out to be complex due to the large interaction among plant biomass, runoff and erosion. This may cause increase or decrease the overall erosion.

MacIntyre's Critique of Modern Moral Pluralism (매킨타이어의 현대 도덕 다원주의 비판)

  • Kim, Young-kee
    • Journal of Korean Philosophical Society
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    • v.137
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    • pp.57-79
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    • 2016
  • The purpose of this paper is to explain MacIntyre's critique of moral pluralism of modern society and reveal the limits of his critique of liberalism. It is a distinctive feature of the social and cultural order that we inhabit that disagreements over central moral issues are peculiarly unsettleable. Debates concerned with the value of human life such as those over abortion and euthanasia, or about distributive justice and property rights, or about war and peace degenerate into confrontations of assertion and counter-assertion because the protagonists of rival positions invoke incommensurable forms of moral assertion against each other. We usually call this situation 'modern moral pluralism' and concede as the natural outcome of the activities of human reason under free institution. But in After Virtue, MacIntyre vigorously criticizes modern moral pluralism. The main cause he took which brought about this state of affairs was the failure of 'the Enlightenment project'. According to MacIntyre, the Enlightenment project which has dominated philosophy for the past three hundred years promised a conception of rationality independent of historical and social context, and independent of any specific understanding of man's nature or purpose. But not only has that promise in fact been unfulfilled, the project is itself fundamentally flawed and the promise could never be fulfilled. In consequence, modern moral and political thought are in a state of disarray from which they can be rescued only if we revert to an Aristotelian paradigm, with its essential commitment, and construct an account of practical reason premised on that commitment. But one of the deepest difficulties with the argument of After Virtue is that the very extent of its critique of the modern world seems to cast doubt on the possibility of any realistic revival under the conditions of modernity of the Aristotelianism which MacIntyre advocates. Especially when we consider we are not only the characters found in our narratives but also we ourselves are the author of our own narratives. Moral pluralism is not seen as disaster but rather as the natural outcome of the activities of human reason under enduring free institutions.

Proanthocyanidins Suppresses Lipopolysaccharide-stimulated Inflammatory Responses via Heme Oxygenase-1 Induction in RAW264.7 Macrophages (프로안토시아니딘의 항염증효과)

  • Cheon, Hye-Jin;Park, Sun Young;Jang, Hee-Ji;Cho, Da-Young;Jung, Jiwon;Park, Gimin;Jeong, Kyeong Mi;Kim, Jin-Kyung
    • Journal of Life Science
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    • v.29 no.4
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    • pp.484-491
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    • 2019
  • Proanthocyanidins are naturally occurring polyphenolic compounds abundant in many vegetables, plant skins (rind/bark), seeds, flowers, fruits, and nuts. Numerous in vitro and in vivo studies have demonstrated myriad effects potentially beneficial to human health, such as antioxidation, immunomodulation, DNA repair, and antitumor activity. Among immune cells, macrophages are crucial players in a variety of inflammatory responses to environmental conditions. However, it has been widely reported that macrophages cause chronic inflammation and are involved in a variety of diseases, such as obesity, diabetes, metabolic syndrome, and cancer. In this study, we report the suppressive effect of proanthocyanidins via the heme oxygenase-1 (HO-1)-related system, on the immune response of the LPS-stimulated mouse macrophage cell line RAW264.7. Increased HO-1 expression at mRNA and protein levels were found in proanthocyanidins-treated RAW264.7 cells. Further, proanthocyanidins enhanced nuclear factor-erythroid 2-related factor 2 translocation into the nucleus. RAW264.7 cells were treated with lipopolysaccharide (LPS) with or without proanthocyanidins, and inflammatory mediator expression levels were assessed. Proanthocyanidins treatment resulted in the attenuation of nitric oxide production and inducible nitric oxide synthase expression in LPS-stimulated RAW264.7 cells. In addition, mRNA and protein expression of proinflammatory cytokines, such as tumor necrosis factor-${\alpha}$ and interleukin-6, was inhibited by proanthocyanidins treatment in LPS-stimulated RAW264.7 cells. These findings support proanthocyanidins as a promising anti-inflammatory agent.

The Historical Origin of the Conflict of the Aymara of Peru and Bolivia, Centered on Puno (페루 - 볼리비아 접경 푸노(Puno) 지역 아이마라(Aymara)원주민 종족갈등의 원인)

  • Cha, Kyung-Mi
    • Cross-Cultural Studies
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    • v.41
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    • pp.351-379
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    • 2015
  • In the Andes regions of Latin America continents, groups of diverse native tribes are intensively distributed.Among these tribes, the Aymara compose the most representative group of natives along with the Quechua. Especially, the Aymara who are concentrated on the border areas of Peru and Bolivia centered on Lake Titicaca have pursued common identity forming the same cultural area although they belong to different nations. In the meantime, the Aymara have maintained a sense of fellowship while emphasizing historicity and specialty, which are differentiated with groups of other natives based on a language constituting identity of the tribe. However, recently, focused on Puno State as the center of the border areas of both countries, the tribe's conflicts come to the surface. After being divided by the artificial boundary line, which was formed in the course of building modern countries after the independence, natives of Latin America started to emphasize differences simultaneously with cultural similarity in the frame of cooperation and competition. Together with the historical contexts, lately, focused on the border areas of Peru and Bolivia, as the same tribe came to be bound by the frameworks of different nations respectively, a new tribal conflict is being developed. Though the Aymara unite emphasizing cultural and historical specialty and recognizing them as one tribe, when they conflict with each other over inner interest, a tendency to form the identity of differentiation and distinction appeared even in the inside of the tribe. Usually, disorder between tribes seems to be originated from intertribal strife, which coexists in one region. In case of the Aymara of Peru and Bolivia, centered on Puno State where both countries maintain the border, an aspect that the fellowship of the tribe, which was established through old history changes into conflict structures by realistic conditions comes out. In understanding this point, this study analyzed the historical origin of the conflict of the Aymara and the deepened cause of the tribal disorder.

Influence of El Niño on the Production of Spring Kimchi Cabbage in South Korea (국내 노지 봄배추 생산량에 대한 엘니뇨 영향)

  • Shim, Kyo-Moon;Kim, Yongseok;Jung, Myung-Pyo;Kim, Ji-Won;Kang, Kee-Kyung
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.20 no.4
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    • pp.330-336
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    • 2018
  • El $Ni{\tilde{n}}o$ would cause extreme weather conditions, which would result in a negative impact on crop production. The objective of this study was to assess the impact of El $Ni{\tilde{n}}o$ on spring kimchi cabbabe production for the period from 1981- 2016 in South Korea. In this study, years with less than 1.0 Oceanic $Ni{\tilde{n}}o$ index were classified into non El $Ni{\tilde{n}}o$ years. The other years were classified as El $Ni{\tilde{n}}o$ years. The national average production of spring kimchi cabbage in El $Ni{\tilde{n}}o$ years ($3,800kg\;10a^{-1}$) tended to be less than that in non El $Ni{\tilde{n}}o$ years ($4,016kg\;10a^{-1}$). However, there was no significant differences (p = 0.078) in the production between these groups of years. The averaged production of spring kimchi cabbage of El $Ni{\tilde{n}}o$ end years ($3,707{\pm}331kg\;10a^{-1}$) was less than those of El $Ni{\tilde{n}}o$ start years and non El $Ni{\tilde{n}}o$ years by 186 and $309kg\;10a^{-1}$, respectively. Still, such difference was not significant statistically (p=0.127), either. In contrast, there were provinces where the production of spring kimchi cabbage had significant differences by El $Ni{\tilde{n}}o$ occurrence. For example, El $Ni{\tilde{n}}o$ end years had significantly less spring kimchi cabbage production than El $Ni{\tilde{n}}o$ start years and non El $Ni{\tilde{n}}o$ years in Gangwon (p=0.038) and Gyeongbuk (p=0.053) provinces. It appeared that differences in cabbage production resulted from short sunshine duration, which merits further analysis on the impact of extreme weather condtions during El $Ni{\tilde{n}}o$ years on crop production.

Optimal Operation of Gas Engine for Biogas Plant in Sewage Treatment Plant (하수처리장 바이오가스 플랜트의 가스엔진 최적 운영 방안)

  • Kim, Gill Jung;Kim, Lae Hyun
    • Journal of Energy Engineering
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    • v.28 no.2
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    • pp.18-35
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    • 2019
  • The Korea District Heating Corporation operates a gas engine generator with a capacity of $4500m^3 /day$ of biogas generated from the sewage treatment plant of the Nanji Water Recycling Center and 1,500 kW. However, the actual operation experience of the biogas power plant is insufficient, and due to lack of accumulated technology and know-how, frequent breakdown and stoppage of the gas engine causes a lot of economic loss. Therefore, it is necessary to prepare technical fundamental measures for stable operation of the power plant In this study, a series of process problems of the gas engine plant using the biogas generated in the sewage treatment plant of the Nanji Water Recovery Center were identified and the optimization of the actual operation was made by minimizing the problems in each step. In order to purify the gas, which is the main cause of the failure stop, the conditions for establishing the quality standard of the adsorption capacity of the activated carbon were established through the analysis of the components and the adsorption test for the active carbon being used at present. In addition, the system was applied to actual operation by applying standards for replacement cycle of activated carbon to minimize impurities, strengthening measurement period of hydrogen sulfide, localization of activated carbon, and strengthening and improving the operation standards of the plant. As a result, the operating performance of gas engine # 1 was increased by 530% and the operation of the second engine was increased by 250%. In addition, improvement of vent line equipment has reduced work process and increased normal operation time and operation rate. In terms of economic efficiency, it also showed a sales increase of KRW 77,000 / year. By applying the strengthening and improvement measures of operating standards, it is possible to reduce the stoppage of the biogas plant, increase the utilization rate, It is judged to be an operational plan.

Evaluation of the usefulness of prone position for reducing the image distortion due to respiration in PET/CT (PET/CT 검사 시 호흡에 따른 영상 왜곡 감소를 위한 엎드린 자세의 유용성 평가)

  • Lee, Han Wool;Kim, Jung Yul;Choi, Yong Hoon;Lim, Han Sang;Kim, Jae Sam
    • The Korean Journal of Nuclear Medicine Technology
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    • v.23 no.1
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    • pp.59-63
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    • 2019
  • Purpose The motion due to respiration of patients undergoing PET/CT is a cause of artifacts in image and registration error between PET and CT images. The degree of displacement and distortion for tumor, which affects the measurement of Standard Uptake Value (SUV) and lesion volume, is especially higher for tumors that is small or located at the base of lungs. The purpose of this study was to evaluate the usefulness of prone position in the correction of image distortion due to respiration of patients in PET/CT. Materials and Methods The imaging equipment used in this study was PET/CT Discovery 600 (GE Healthcare, MI, USA). 20 patients whose lesions were identified in the middle and lower lungs from May to August 2018 were enrolled in this study. After acquiring whole body image in the supine position, additional images of the lesion area were obtained in the prone position with the same conditions. SUVmax, SUVmean, and volume of the lesion were measured for each image, and the displacement of the lesion on PET and CT images were measured, compared, and analyzed. Results The SUVmax, SUVmean, and volume, and displacement of the lesion were $4.72{\pm}2.04$, $3.10{\pm}1.38$, $4.68{\pm}3.20$, and $4.64{\pm}1.88$, respectively for image acquired in the supine position and $5.89{\pm}2.42$, $3.97{\pm}1.65$, $2.13{\pm}1.09$, and $2.24{\pm}0.84$, respectively for image acquired in the prone position, indicating that, for all the lesions imaged, SUVmax and SUVmean were higher and volume and displacement were smaller in the images acquired in prone position compared to those acquired in supine one(p<0.05). Conclusion These results showed that the prone position PET/CT imaging improves the quality of the image by increasing the SUV of the lesion and reducing the respiratory artifacts caused by registration error between PET and CT images. It is considered that the PET/CT imaging in the prone position is helpful in the diagnosis of the disease as an economical and efficient methods that correct registration error for the lesions in basal lung and reduce artifacts.

Scale-up Study of Heterogeneous Catalysts for Biodiesel Production from Nepalese Jatropha Oil (네팔산 자트로파 오일로부터 바이오디젤 제조를 위한 불균일계 촉매 Scale-up 연구)

  • Sim, Minseok;Lee, Seunghee;Kim, Youngbin;Ku, Huiji;Woo, Jaegyu;Joshi, Rajendra;Jeon, Jong-Ki
    • Clean Technology
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    • v.27 no.2
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    • pp.198-204
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    • 2021
  • This study focused on a two-step process using heterogeneous catalysts to produce biodiesel using Nepalese jatropha oil as a raw material. As a first step, the effect of the repetitive regeneration number of Amberlyst-15 on the esterification reaction of FFA in jatropha oil was investigated. Second, the possibility of a transesterification reaction scale-up using a dolomite bead catalyst was tested. Using 120 kg of jatropha seeds from Nepal, 30 L (27 kg) of jatropha oil was obtained, and the jatropha oil yield from the seeds was about 25.0 wt%. The acid value and FFA content of jatropha oil were measured to be 11.3 mgKOH g-1 and 5.65%, respectively. As a result of the esterification reaction of jatropha oil using the Amberlyst-15 catalyst in the form of beads, the acid value of the reaction product could be lowered to 0.26 mgKOH g-1 when the fresh Amberlyst-15 catalyst was used. As the regeneration of the Amberlyst-15 catalyst is repeated, the catalyst has been deactivated, and the esterification reaction performance has deteriorated. The cause of the deactivation seems to be due to the catalyst being broken and impurities being deposited. It was confirmed that the Amberlyst-15 catalyst could be reused up to 5 times for the esterification reaction of jatropha oil. In the second step, the transesterification reaction, a dolomite catalyst, was mass-produced and used in the form of beads. By transesterifying the pretreated jatropha oil in a spinning catalyst basket reactor equipped with 90 g of dolomite bead catalyst, 89.1 wt% of biodiesel yield was obtained in 2 hours after the start of the reaction, which was similar to the transesterification of soybean oil under the same conditions.

Analysis of Behavior of Seoullo 7017 Visitors - With a Focus on Text Mining and Social Network Analysis - (서울로 7017 방문자들의 이용행태 분석 -텍스트 마이닝과 소셜 네트워크 분석을 중심으로-)

  • Woo, Kyung-Sook;Suh, Joo-Hwan
    • Journal of the Korean Institute of Landscape Architecture
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    • v.48 no.6
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    • pp.16-24
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    • 2020
  • The purpose of this study is to analyze the usage behavior of Seoullo 7017, the first public garden in Korea, to understand the usage status by analyzing blogs, and to present usage behavior and improvement plans for Seoullo 7017. From June 2017 to May 2020, after Seoullo 7017 was open to citizens, character data containing 'Seoullo 7017' in the title and contents of NAVER and·DAUM blogs were converted to text mining and socialization, a Big Data technique. The analysis was conducted using social network analysis. The summary of the research results is as follows. First of all, the ratio of men and women searching for Seoullo 7017 online is similar, and the regions that searched most are in the order of Seoul and Gyeonggi, and those in their 40s and 50s were the most interested. In other words, it can be seen that there is a lack of interest in regions other than Seoul and Gyeonggi and among those in their 10s, 20s, and 30s. The main behaviors of Seoullo 7017 are' night view' and 'walking', and the factors that affect culture and art are elements related to culture and art. If various programs and festivals are opened and actively promoted, the main behavior will be more varied. On the other hand, the main behavior that the users of Seoullo 7017 want is 'sit', which is a static behavior, but the physical conditions are not sufficient for the behavior to occur. Therefore, facilities that can cause sitting behavior, such as shades and benches must be improved to meet the needs of visitors. The peculiarity of the change in the behavior of Seoullo 7017 is that it is recognized as a good place to travel alone and a good place to walk alone as a public multi-use facility and group activities are restricted due to COVID-19. Accordingly, in a situation like the COVD-19 pandemic, more diverse behaviors can be derived in facilities where people can take a walk, etc., and the increase of various attractions and the satisfaction of users can be increased. Seoullo 7017, as Korea's first public pedestrian area, was created for urban regeneration and the efficient use of urban resources in areas beyond the meaning of public spaces and is a place with various values such as history, nature, welfare, culture, and tourism. However, as a result of the use behavior analysis, various behaviors did not occur in Seoullo 7017 as expected, and elements that hinder those major behaviors were derived. Based on these research results, it is necessary to understand the usage behavior of Seoullo 7017 and to establish a plan for spatial system and facility improvement, so that Seoullo 7017 can be an important place for urban residents and a driving force to revitalize the city.

A Study on the Development of High Sensitivity Collision Simulation with Digital Twin (디지털 트윈을 적용한 고감도 충돌 시뮬레이션 개발을 위한 연구)

  • Ki, Jae-Sug;Hwang, Kyo-Chan;Choi, Ju-Ho
    • Journal of the Society of Disaster Information
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    • v.16 no.4
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    • pp.813-823
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    • 2020
  • Purpose: In order to maximize the stability and productivity of the work through simulation prior to high-risk facilities and high-cost work such as dismantling the facilities inside the reactor, we intend to use digital twin technology that can be closely controlled by simulating the specifications of the actual control equipment. Motion control errors, which can be caused by the time gap between precision control equipment and simulation in applying digital twin technology, can cause hazards such as collisions between hazardous facilities and control equipment. In order to eliminate and control these situations, prior research is needed. Method: Unity 3D is currently the most popular engine used to develop simulations. However, there are control errors that can be caused by time correction within Unity 3D engines. The error is expected in many environments and may vary depending on the development environment, such as system specifications. To demonstrate this, we develop crash simulations using Unity 3D engines, which conduct collision experiments under various conditions, organize and analyze the resulting results, and derive tolerances for precision control equipment based on them. Result: In experiments with collision experiment simulation, the time correction in 1/1000 seconds of an engine internal function call results in a unit-hour distance error in the movement control of the collision objects and the distance error is proportional to the velocity of the collision. Conclusion: Remote decomposition simulators using digital twin technology are considered to require limitations of the speed of movement according to the required precision of the precision control devices in the hardware and software environment and manual control. In addition, the size of modeling data such as system development environment, hardware specifications and simulations imitated control equipment and facilities must also be taken into account, available and acceptable errors of operational control equipment and the speed required of work.