• Title/Summary/Keyword: 증감제

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Behavior of Fill Dam Subjected to Continuous Water Level Change and Overflow (지속적 수위변동 및 월류에 따른 저수지 제체의 거동 연구)

  • Lee, Chungwon;Maeng, Youngsu;Kim, Yongseong
    • Journal of the Korean GEO-environmental Society
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    • v.15 no.6
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    • pp.41-48
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    • 2014
  • In this study, the behavior of fill dam with continuous water level change considering velocity changes via centrifugal model test was investigated. In addition, the collapse of fill dam due to the overflow was also experimentally simulated. The experimental results demonstrate that the pore water pressures and displacements vary in proportion to the water-level-change velocity, and the displacement increment is independent to the water-level-change velocity. Also, it is confirmed that the continuous water level change induces to the progress of fill-dam deformation due to displacement accumulation and the fill-dam stability dramatically degrades owing to the overflow. Hence, the real-time monitoring of pore water pressures and displacements of fill dam, and the control of water level in heavy rain through the countermeasure such as opening sluice gates are needed to ensure the stability of fill dam.

Spatial Optimization Approaches to Redistricting for National Assembly Election: A Case Study on Yongin City (공간 최적화 기법을 이용한 국회의원 선거구 획정 -용인시를 사례로-)

  • Kim, Myung Jin;Kim, Kamyoung
    • Journal of the Korean Geographical Society
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    • v.48 no.3
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    • pp.387-401
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    • 2013
  • Redistricting of National Assembly Election has a significant effect on the results of election because it has a strong tendency to be performed with political intentions rather than the equivalent representativeness of population and region. This paper focuses on proposing an alternative for restricting of National Assembly Election in terms of implementation, that is, an procedural and systematic approach, not allowing for political or arbitrary intervention. A spatial optimization model conforming with criteria for political redistricting such as population equality, contiguity, and spatial compactness is developed and applied to Yongin City where are some controversy over the redistricting of the 19th National Assembly. Modeling results show that it is possible to derive National Assembly Election districts based on the information of basic spatial units without political consideration or arbitrary intervention. In addition, The districts derived from the model improved population equality compared with the existing districts.

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Alteration in the Transferrin Receptor during the Chick Myoblast Fusion in Culture (계배 근원세포의 융합에 따른 Transferrin 수용체의 변화)

  • 이창호;유병제;전영주;정진하;하두봉
    • The Korean Journal of Zoology
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    • v.32 no.2
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    • pp.163-175
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    • 1989
  • Transferrin (Tf) has been known to exert profound effect on the myoblast differentiation in uirto. Therefore, the changes in the amount and affinity of the Tf receptor would accompany the myoblast differentiation. To investigate this possibility, we exarnined the afteration pattern in the level of the Tf receptor during the myoblast fusion. The level of Tf receptor was assayed by measuring the bound 125 I-Tf onto the surface of cultured myoblasts, and it was known that the level of Tf receptor reached the maximum at about 12 hr before the initi ation of the myoblast fusion and decreased as the differentiation proceeded, and that the affinity of Tf receptor to Tf was also decreased. In addition, various inhibitiors of the myoblast fusion also influenced the level of the Tf receptor. Accroding to these results, it is postulated that the level of Tf receptor is highly regulated during the myoblast differentiation.

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A Study on the Material Properties of Admixed Liners for Waste Fill (폐기물 매립장을 위한 혼합 차수재의 물성에 관한 연구)

  • Son, Jun-Ik;Jeong, Ha-Ik;Jang, Yeon-Su
    • Geotechnical Engineering
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    • v.8 no.3
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    • pp.51-60
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    • 1992
  • This paper represents the physical and engineering characteristics of admixed liners obtained from several laboratory tests. Fly ash and weathered granitic soil are selected as primary materials, and bentonite and cement are used as additives. The results show that the maximum dry density reaches peak values at 5% and 25% of bentonite for Seochon and Samchonpo fly ash respectively, and for the weathered granitic soil, the maximum dry density increases continuously as the amount of bentonite increases. The strength of the admixed materials is not sensitive to the bentonite content, although it increases when the additives is cement. The required amount of bentonite to reach the hydraulic conductivity less than 10-7cm/sec are 18, 30, 10% of the sample weights for Seochon and Samchonpo fly ashes and the weathered granitic soil. The amount of additives show significant differences and depend on the grain size and their distributions and the amount of fine content in the primary materials

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A Study on the Fluidity Retention of Cement Paste Added by Naphthalene Sulfonated Condensate and Polycarboxylic Acid Admixture (나프탈렌술폰산축합물과 폴리카르본산계 혼화제가 첨가된 시멘트 페이스트의 유동성 유지에 관한 연구)

  • 노재성;홍성수;김도수
    • Magazine of the Korea Concrete Institute
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    • v.7 no.5
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    • pp.189-199
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    • 1995
  • Naphthalene sulfonated condensate has been widely used as a superplasticizer for cement and concrete, but the application was limited due to its large slump loss with elapsed time. To complement this demerit of NSF, polycarboxylic acid copolymer from nlaleic anhydride and acryl~c acid(MA) was synthesized to retain the mobility of cement and concrete, and then mixed with NSF. The physical properties, such as fluidity, fluidityretention and rheology, were measured by applying these admixtures to cement paste as a function of elapsed time. And also compressive strength of mortar was measured with curing time. NIv-l and NM-2 containing 10, 20 wt% of MA respectively had a excellent fluidity and a fluidity- retention. In rheological property, the increases of shear stress and viscosity with elapsed time were delayed with the increasing of shear rate in cornparision with NSF only. The marked slump loss of cement paste could be controlled by these admixture. Also the added ainount of admixture and the ratio of water to cement affected these properties.

Trends Analysis on Research Articles in the Journal of Korean Society for Information Management (『정보관리학회지』 연구의 동향분석)

  • Seo, Eun-Gyoung
    • Journal of the Korean Society for information Management
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    • v.27 no.4
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    • pp.7-32
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    • 2010
  • The aims of this study were to provide a global overview of research trends in information science and to trace its changes in the main research topics over time using trends analysis. The study examined the topics of research articles published in Journal of Korean Society for Information Management between 1984 and 2009. Rather than taking a single snapshot of a given point in time, this study attempted to present a series of such pictures in order to identify trends over time. The fairly arbitrary decision was taken to divide the period under consideration into three 'publication windows': 1984-1994, 1995-2002, 2003-2009. The study revealed that the most productive areas were 'Information Service', followed by 'Information Organization', and 'Information System'. The most productive sub-areas were 'Library Service', 'User Study', 'Automatic Document Analysis', 'ILS', 'Thesaurus/Ontology', and 'Digital Library'. From the comparisons of intellectual structures of title keywords, the key research area in the field of Information Science was 'Information Retrieval'. The studies of IT applications and service system evaluation have been expanded.

A Study on the TV Audition Show's Distortion of Reality with Sartre's Existentialism which shows Media Subjectivity and Ethicality (오디션 프로그램의 리얼리티 왜곡이 보여주는 미디어의 주관성과 윤리성)

  • Tu, Lingyao
    • Trans-
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    • v.11
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    • pp.1-35
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    • 2021
  • This study looks to explore situations in which the authenticity of reality audition programs is inherently distorted by subjective intervention through a theoretical model of existentialism and case study of how it was practiced in an actual program. In detail, we examine the impact on the essence of human subjective intervention and the behavior by free will and use Sartre's existentialism a theoretical model and a Korean audition program series as the case for the study. We believe that the producers intended to narrow the audiences choices by creating a favorable environments for certain participants (trainees as they were called) to be recognized and liked by the voting audiences. We look to "subjectivity," the first principle of existentialism, people determine their essence through free will, and all actions in the production process are aimed at achieving that goal, which keeps the position balance of final debut group by creating the character image and personality through character making, storytelling and increasing or decrease the assigned air-time of each individuals.

Groundwater management strategies for sustainability of field farming water supply (밭용수 공급의 지속가능성 확보를 위한 지하수 관리 전략)

  • Cha, Eunji;Hyun, Yunjung;Lee, Gu-Sang;Jeong, Ayoung
    • Proceedings of the Korea Water Resources Association Conference
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    • 2022.05a
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    • pp.78-78
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    • 2022
  • 농가인구의 감소 및 고령화, 고소득 작물 재배, 기후변화 등으로 인해 영농형태가 논농사에서 밭농사로 전환되고 지역별 증감의 차이가 있기는 하나 밭 면적이 증가하는 추세를 보인다. 한편, 밭작물은 논에 비해 기반시설이 부족하고 고소득의 밭작물을 생산하기 위한 시설재배가 늘어나면서 대부분 사계절 확보가 용이하고 수질이 양호한 지하수를 사용하고 있다. 지하수 수요 증가는 지하수위 저하와 지하수 고갈의 우려를 초래하고 있다. 본 연구에서는 농업용 지하수 이용 실태를 분석하고 지하수이용 및 관리 제도 현황을 검토하여 지속가능한 밭용수 공급을 위한 지하수 관리전략을 제안하였다. 진주시를 대상으로 경지유형에 따른 지하수 이용 특성 분석하여 지하수의 수요 특성을 살펴보았는데, 하천 주변 저지대에 큰규모의 밭이나 집단화된 시설재배 지역이 분포하고 있고 지하수 관정도 밀집하고 있었다. 하천에서 떨어진 산간지역에는 지하수 관정이 산발적으로 분포하고 있었다. 지하수 수요는 공간적 위치 외에도 고품질 농업용수에 대한 요구도 원인인 것으로 조사되었다. 밭기반 용수공급 관련 사업과 지하수 자원확보 관련 법제도 등을 고찰하여 밭의 위치, 규모, 용수공급의 수요 특성 등을 고려하여 밭용수 공급을 위한 세 가지 지하수 관리전략을 제안하였다. 우선, 농업용 지하수 이용량 실측 및 정보의 다각화를 통한 정보의 고도화가 필요하다. 둘째, 지하수 이용의 공간적 특성을 고려하여 지표수와 연계한 지하수 이용기반이 구축되어야 한다. 지표수 공급이 가능한 지역은 지표수를 우선 공급하거나 지하수와 혼합 또는 교차하여 공급하고 물공급 취약지역에서는 지하수 공급 기반시설을 구축하는 것이다. 세 번째 전략은 농업용 지하수 시설의 공공관리 강화 및 관리 효율화이다. 특히 지하수이용이 밀집한 지역에서는 지하수 인허가 기준을 강화하고 용도별 관리체계 구축이 필요하다. 밭용수 공급은 농가 소득과 밀접한 연관이 있기 때문에 물이용의 지속가능성과 함께 농가 소득증대를 고려하는 공편인적 관점에서의 관리가 필요할 것으로 생각된다.

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Effect of Micro Bubble on Growth of Ginseng in the shaded plastic houses and Possibility of High Quality Ginseng processing (하우스 종묘삼 재배에서 마이크로 버블(Micro bubble) 사용이 생육에 미치는 영향과 고품질 인삼 가공의 가능성)

  • Ahn, C.H.
    • Journal of Practical Agriculture & Fisheries Research
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    • v.19 no.1
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    • pp.109-117
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    • 2017
  • In the production of organic Panax ginseng, the morphological changes were confirmed by providing general water and microbubble water, respectively. Analysis of seedling ginseng treated with general water and bubbles water revealed that many seedlings were formed in the seedling treated with bubble water, and about 15% weight increase occurred in the growing period. The growth rate of stem, leaf, and root was about 15% higher than that of all. Taken together, the growth of seedling cultivation using bubble water was about 15% overall. In order to process ginseng, the dried ginseng was higher in dry weight than the general water seedling seedlings grown in bubble water. This suggests that more processed products will be produced per unit weight at the time of producing the processed products at the farm, which can directly increase the farm income.

Evaluation of Agro-Climatic Index Using Multi-Model Ensemble Downscaled Climate Prediction of CMIP5 (상세화된 CMIP5 기후변화전망의 다중모델앙상블 접근에 의한 농업기후지수 평가)

  • Chung, Uran;Cho, Jaepil;Lee, Eun-Jeong
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.17 no.2
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    • pp.108-125
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    • 2015
  • The agro-climatic index is one of the ways to assess the climate resources of particular agricultural areas on the prospect of agricultural production; it can be a key indicator of agricultural productivity by providing the basic information required for the implementation of different and various farming techniques and practicalities to estimate the growth and yield of crops from the climate resources such as air temperature, solar radiation, and precipitation. However, the agro-climate index can always be changed since the index is not the absolute. Recently, many studies which consider uncertainty of future climate change have been actively conducted using multi-model ensemble (MME) approach by developing and improving dynamic and statistical downscaling of Global Climate Model (GCM) output. In this study, the agro-climatic index of Korean Peninsula, such as growing degree day based on $5^{\circ}C$, plant period based on $5^{\circ}C$, crop period based on $10^{\circ}C$, and frost free day were calculated for assessment of the spatio-temporal variations and uncertainties of the indices according to climate change; the downscaled historical (1976-2005) and near future (2011-2040) RCP climate sceneries of AR5 were applied to the calculation of the index. The result showed four agro-climatic indices calculated by nine individual GCMs as well as MME agreed with agro-climatic indices which were calculated by the observed data. It was confirmed that MME, as well as each individual GCM emulated well on past climate in the four major Rivers of South Korea (Han, Nakdong, Geum, and Seumjin and Yeoungsan). However, spatial downscaling still needs further improvement since the agro-climatic indices of some individual GCMs showed different variations with the observed indices at the change of spatial distribution of the four Rivers. The four agro-climatic indices of the Korean Peninsula were expected to increase in nine individual GCMs and MME in future climate scenarios. The differences and uncertainties of the agro-climatic indices have not been reduced on the unlimited coupling of multi-model ensembles. Further research is still required although the differences started to improve when combining of three or four individual GCMs in the study. The agro-climatic indices which were derived and evaluated in the study will be the baseline for the assessment of agro-climatic abnormal indices and agro-productivity indices of the next research work.