• 제목/요약/키워드: Value Improvement

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해안간척지 토양의 생물학적 토성개량에 관한 연구 (제1보) 수종 염생식물에 의한 간 탁지토양의 제염효과에 대하여 (Biological Improvement of Reclaimed Tidal Land (I) Desalination Effects of Saline Soil by the Growth of certain Halophytes)

  • 홍순우
    • Journal of Plant Biology
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    • 제12권1호
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    • pp.7-14
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    • 1969
  • Korea has a lots of margin for security of farm land from her coastal region. The area of saline soil may be reached about 10% of present farm land if the reclamation works are finished. This paper was conducted as a part of studying the possibilities of desalination of saline soil through the experiment of some halophytes. The halophytes in this works were Salicornia herbacea L., Suaeda glauca Bunge, chenopodium acuminatum Willd, and Scirpus triquerter L. Of the above halophytes, Salicornia was proved the most effective plant for desalination of saline soil referring to the following results; 1) The seasonal uptake of chloride by Salicornia was the highest of all. However, the general tendencies of all plants showed a decrease on August. 2) Salinity of soil showed the lowest value on the site where Salicornia was grwon densely. Comparing the other sites grouped by age of saline soil with the above site, the salinity of rice-paddy (10 years after reclamation) is similar to those of the site wehre Salicornia were as well as the 50 cm below the surface soil. 3) The maximum water holding capacity of surface soil appeared in the site of Salicornia, but in 50 cm below the surface, the maximum water holding capacity are almost on equat terms having no connection with the age of saline soil. Soil pH, other chemical compositions such as organic matter, magnesium, potassium, phosphorous, and nitrate were determined to elucidate the relationship between the changes of soil properties and chemical uptakes by certain halophytes. It is assumed that the above chemical compositions are frequently affected by the factors such as coastal circulation of salts, exchangeable base, microbial growth, climatic conditions, and irrigation of water.

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Threshold Subsoil Bulk Density for Optimal Soil Physical Quality in Upland: Inferred Through Parameter Interactions and Crop Growth Inhibition

  • Cho, Hee-Rae;Han, Kyung-Hwa;Zhang, Yong-Seon;Jung, Kang-Ho;Sonn, Yeon-Kyu;Kim, Myeong-Sook;Choi, Seyeong
    • 한국토양비료학회지
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    • 제49권5호
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    • pp.548-554
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    • 2016
  • Optimal range of soil physical quality to enhance crop productivity or to improve environmental health is still in dispute for the upland soil. We hypothesized that the optimal range might be established by comparing soil physical parameters and their interactions inhibiting crop growth. The parameter identifying optimal range covered favorable conditions of aeration, permeability and root extension. To establish soil physical standard two experiments were conducted as follows; 1) investigating interactions of bulk density and aeration porosity in the laboratory test and 2) determining effects of soil compaction and deep & conventional tillage on physical properties and crop growth in the field test. The crops were Perilla frutescens, Zea mays L., Solanum tuberosum L. and Secale cereael. The saturated hydraulic conductivity, bulk density from the root depth, root growth and stem length were obtained. Higher bulk density showed lower aeration porosity and hydraulic conductivity, and finer texture had lower threshold bulk density at 10% aeration bulk density. Reduced crop growth by subsoil compaction was higher in silt clay loam compared to other textures. Loam soil had better physical improvement in deep rotary tillage plot. Combined with results of the present studies, the soil physical quality was possibly assessed by bulk density index. Threshold subsoil bulk density as the upper value were $1.55Mg\;m^{-3}$ in sandy loam, $1.50Mg\;m^{-3}$ in loam and $1.45Mg\;m^{-3}$ in silty clay loam for optimal soil physical quality in upland.

협업 필터링 추천 시스템을 위한 데이터 신뢰도 기반 가중치를 이용한 하이브리드 선호도 예측 기법 (Hybrid Preference Prediction Technique Using Weighting based Data Reliability for Collaborative Filtering Recommendation System)

  • 이오준;백영태
    • 한국컴퓨터정보학회논문지
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    • 제19권5호
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    • pp.61-69
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    • 2014
  • 협업 필터링 추천은 사용자의 아이템에 대한 선호도를 기반으로 유사 아이템 집합 또는 유사 사용자 집합을 생성하고 이를 이용해 사용자의 특정 아이템에 대한 선호도를 예측한다. 따라서 선호도 행렬이 희박할 경우, 추천의 신뢰도는 급격히 낮아진다. 본 논문에서는 위 문제를 해결하기 위해 데이터 신뢰도 기반 가중치를 이용한 하이브리드 선호도 예측 기법을 제안한다. 선호도 예측은 유사 아이템 집합과 유사 사용자 집합을 모두 생성하고 각 집합을 통해 사용자의 선호도를 예측하며, 모델의 상황을 반영한 가중치를 이용해 각 예측치를 병합하여 수행된다. 이 기법은 사용자 선호도 예측 정확도를 높이며 선호도 행렬 희박도가 높은 상황에도 추천 서비스의 신뢰도를 유지할 수 있도록 한다. 이 기법을 바탕으로 추천 시스템을 구현하고 절대평균오차를 기준으로 서비스 신뢰도 향상을 측정하였다. 실험에서 본 기법은 Hao Ji가 제안한 기존의 기법에 비해 선호도 행렬 희박도가 84% 이상인 상황에서 평균 21.7%의 성능 향상을 보여 효과적으로 행렬 희박도 문제를 해소할 수 있음을 검증하였다.

물분해용 Fe2O3/Na2Ti6O13/FTO 박막 제조 및 특성평가 (Fabrication and (Photo)Electrochemical Properties of Fe2O3/Na2Ti6O13/FTO Films for Water Splitting Process)

  • 윤강섭;구혜경;강우승;김선재
    • Corrosion Science and Technology
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    • 제11권2호
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    • pp.65-69
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    • 2012
  • One dimensional(1D) $Na_2Ti_6O_{13}$ nanorods with 70 nm in diameter was synthesized by a molten salt method. Using the synthesized nanorods, about 750 nm thick $Na_2Ti_6O_{13}$ film was coated on Fluorine-doped tin oxide(FTO) glasss substrate by the Layer-by-layer self-assembly(LBL-SA) method in which a repetitive self-assembling of ions containing an opposite electric charge in an aqueous solution was utilized. Using the Kubelka-Munk function, the band gap energy of the 1D-$Na_2Ti_6O_{13}$ nanorods was nalyzed to be 3.5 eV. On the other hand, the band gap energy of the $Na_2Ti_6O_{13}$ film coated on FTO was found to be a reduced value of 2.9 eV, resulting from the nano-scale and high porosity of the film processed by LBL-SA method, which was favorable for the photo absorption capability. A significant improvement of photocurrent and onset voltage was observed with the $Na_2Ti_6O_{13}$ film incorporated into the conventional $Fe_2O_3$ photoelectrode: the photocurrent increased from 0.25 to 0.82 mA/$cm^2$, the onset voltage decreased from 0.95 to 0.78 V.

산사추출액 첨가 양갱의 품질특성 (Quality Characteristics of the Yanggeng made by Crataegi fructus Extracts)

  • 김성수
    • 한국조리학회지
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    • 제21권1호
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    • pp.225-234
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    • 2015
  • 본 연구에서는 산사추출액을 첨가한 양갱을 제조하여 이화학적 제품특성을 분석하였다. 산사추출액 첨가 양갱의 수분함량은 32.0~32.7%로 대조군과 차이를 나타내지 않았다. 산사추출액 첨가량이 증가할수록 양갱의 pH는 6.8~5.1로 낮아지는 경향을 보이고, 산도는 0.1~0.7%로 증가하였다. 양갱의 색도 측정에서 명도(L)와 황색도(b)는 산사추출액 첨가량이 증가함에 따라 감소한 반면에 적색도(a)는 증가하였다. 조직감 측정에서는 산사추출액 함량이 증가함에 따라 대조군에 비해 경도가 최대 14%까지 증가한다. 관능검사에서 맛, 색, 향, 질감 및 전반적인 기호도 평가에서 산사추출액 15%를 첨가한 양갱이 가장 높은 평가결과를 받았다. 이상의 결과를 통하여 우수한 기능성 소재로 각광을 받고 있는 산사추출액을 기능성 양갱 제조 시 첨가량은 앙금 대비 15%가 가장 적당할 것으로 사료되며, 기능성 가공 식품의 제품개발 및 연구에 산사추출액의 활용도를 높여 가공식품 시장에 도입하였으면 한다.

환경쟁점분석 수업이 중학생의 의사 결정력에 미치는 효과 (The Effect of the Environmental Issue Analysis Instruction on the Decision Making Ability of Middle School Students)

  • 송선경;최돈형;백성혜;손연아
    • 한국환경교육학회지:환경교육
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    • 제20권1호
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    • pp.42-61
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    • 2007
  • This study investigated the effect of the environmental issue analysis instruction on the decision making ability of middle school students. A pretest-posttest control group design was employed. The participants for the research were 288 1st grade male students in middle school in Seoul, the environmental issue analysis lesson group consisted of 142 members and the non-environmental education group consisted of 146 members. The cognitive level of the students were divided into three groups-concrete, transition, formal-as the result of GALT test. Students take issue analysis lessons during 6 weeks, one lesson per a week. Students had studied through worksheets reconstructed and developed by researcher on basis of issue analysis suggested by Ramsey et al. (1997). The results of the research were followings: After lesson for environmental issue analysis, all of the students were improved in decision-making ability regardless of cognitive level (p<.05). Especially, decision-making ability of the transition group students was improved to a high degree. Scores of searching relevant information, generation of alternatives, identification of values for selection criteria, the evaluation of alternatives' merits and demerits, prediction of consequence were increased in experimental group (p<.05). But the ability of selection of alternatives according to value was not reached statistically meaningful improvement. The decision-making ability of the control group students was not improved but ability of selection of alternatives, the evaluation of consequence were increased (p<.05).

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법적 증거로서 기록의 활용을 위한 공기업 기록관리 현황분석 및 개선방안 (A Study on the Analysis and Improvement of Public Enterprises' Record Management for the Utilization of Record as Legal Evidence)

  • 박서인;김지현
    • 한국기록관리학회지
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    • 제20권2호
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    • pp.41-65
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    • 2020
  • 모든 조직에서 법적 분쟁은 심각한 위험요인으로 간주되며 업무수행 과정에서 언제든 발생할 수 있어 소송에 적극적으로 대비할 필요가 있다. 특히 기업인 동시에 공공기관인 공기업은 소송의 결과가 경영상 위험을 초래하지 않으면서 공공성을 저해하지 않도록 소송대응에 더욱 특별한 주의를 기울여야 한다. 따라서 본 연구는 효율적 소송대응과 체계적인 기록관리의 관계에 주목하여 공기업 기록관리 현황과 소송에서의 기록 활용 현황 파악과 법적 증거로서 기록 활용을 뒷받침하는 기록관리 개선방안 제안을 목적으로 하였다. 이를 위해 문헌연구와 공기업 기록연구사 6명과 법무업무담당자 5명을 대상으로 심층면담을 수행하였다. 기록이 법적 증거로 활용되기 위해서는 기록의 진본성을 보장하고 잠재적 증거확보를 지원하는 체계적인 기록관리가 필수적이며 기록관리의 중요성에 대한 인식이 강화될 필요가 있다. 더불어 기록의 증거능력을 기반으로 하는 효율적인 소송대응을 위해 기록관리 부서와 법무팀 간 협력의 중요성을 제안하였다.

부산시민을 대상으로 한 생선회 선호도 실태 및 소비촉진 방안 (A Study on Preference and Promoting' Consumption of Slice Raw Fish to Conduct a Questionnaire Survey of Citizens of Busan)

  • 김배의;조영제;심길보
    • 수산해양교육연구
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    • 제17권3호
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    • pp.413-426
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    • 2005
  • The objective of this study consists of facilitating seafood consumption by increasing its intake opportunities for consumer through analysis of sliced raw fish. A study on sliced raw fish consumption was conducted on 630 citizens of Busan(252 men and 378 women), attending high school and university, and employedas housekeepers and salaried employees. The goal of the study was to assess the attitude and degree of satisfaction obtained from eating sliced raw fish and ultimately to promote greater seafood consumption. A self-administered questionnaire was used to record the results. The results were as follows : About sixty percent of the respondents appeared to like or not to be reluctant to eating sliced raw fish. The main reasons for favoring sliced raw fish were its taste and nutritious effects. All ages liked sliced raw fish, but teenaged women, on average, tend to dislike sliced raw fish. The most preferred sliced raw fish was flounder. Most of the panelists preferred korean rock fish, and red sea bream due to their ordinary muscle. Sliced raw fish of the 2nd and 3rd variety were the most popular. For most of the sliced raw fish, the own-price elasticity came out to be relatively low. This can be explained by the fact that sliced raw fish is characteristically purchased based more on quality and freshness, than on price. SINGSINGWHE(SSW)-fresh sliced raw fish should be stored at 0$^{\circ}C$ for no longer than 10hrs. Taste, nutritional value and low price have the potential to promote the consumption of seafood. Factors which can reduce the consumption of sliced raw fish were safety due to Vibrio septicemia, rainy day, indistinct origin, and high rices. To promote sliced raw fish consumption, the subjects recommended the quality improvement and low price.

An E-score Development Methodology for Life Cycle Impact Assessment

  • Young-Min Park;Jai-Rip Cho
    • 산업경영시스템학회지
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    • 제24권68호
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    • pp.51-65
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    • 2001
  • This study is to make LCIA(Life Cycle Impact Assessment) easier as a methodology of environmental scores(called E-score) that integrated environmental load of each emission substance based on environmental damage such as in human health, ecosystem and resources category. The concept is to analyzes the LCI(Life Cycle Inventory) and defines the level of environment damages for human health, ecosystem and resources to objective impact assessment standard, and makes the base of marginal damage to calculate the damage factor, which can present the indication that can establish the standard value of environmental impact. First, damages to human health are calculated by fate analysis, effect analysis and damage analysis to get the damage factor of health effect as a DALY(Disability Adjusted Life Years) unit. Second, damages to ecosystem are calculated by fate analysis, effect analysis and damage analysis to get the damage factor of the effect as a PDF(Potentially Disappeared Fraction) unit through linking potentially increased disappeared fraction. Third, damages to resources are carried out by resource analysis and damage analysis for linking the lower fate to surplus energy conception to get damage factor as a MJ(Mega Joule) unit. For the ranking of relative environment load level each other, LCIA can be carried out effectively by applying this E-score methodology to the particular emission substances. A case study has been introduced for the emission substances coming out of a tire manufacturer in Korea. It is to show how to work the methodology. Based on such study result, product-designers or producers now can apply the E-scores presented in this study to the substances of emission list, and then calculate the environment load of the product or process in advance at any time and can see the environment performance comparatively and expected to contribute to the environmental improvement in view of environmental pollution prevention.

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도시 유역에 위치한 하구를 구성하는 하천의 저영향 개발 기간 산정 (Estimation of low impact development duration of estuaries at urban area)

  • 정안철;임정철;김송현;백충열
    • 한국습지학회지
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    • 제21권4호
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    • pp.290-297
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    • 2019
  • 하구는 하천이 개방해역과 연결되어 있어 담수와 염수가 만나는 전이지대로 생물다양성이 매우 높고 독특한 생태계를 구성하고 있다. 그러나 하구의 생태적 가치를 인식하기 전부터 다양한 훼손 및 교란이 이루어져 왔으며, 이를 위한 대책이 필요한 실정이다. 하구를 구성하는 하천의 하천기본계획은 지속적인 교란요소로 작용하고 있으나, 수재해로부터 인명피해를 최소화하고 하천의 기능을 강화시켜 국가 수자원을 관리하기 위한 공익적 목적이 있다. 따라서 개발과 생태계 보호라는 대립적 관계가 공존할 수 있는 방안에 대한 연구가 필요하다. 본 연구에서는 이를 위해서 환경창이라는 개념을 이용해 하구 생태계가 개발의 부정적인 영향으로부터 교란이 최소화되는 기간인 저영향 개발 기간을 산정하였다. 본 연구에서 제시한 저영향 개발 기간 산정방법은 향후 이루어질 개발사업이나 교란·훼손 행위 등으로부터 생태계를 보호하기 위한 근거 및 기초자료로 활용될 수 있을 것으로 판단된다.