• 제목/요약/키워드: FA test

검색결과 250건 처리시간 0.027초

플라이애시를 대량 사용한 콘크리트의 특성에 관한 실험적 연구 (An Experimental Study on the Properties of High Volume Fly Ash Concrete)

  • 최세진;장종호;최성우;최희용;박선규;김무한
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2000년도 가을 학술발표회논문집(I)
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    • pp.549-554
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    • 2000
  • Generally, it is indicated that concrete using fly ash as a part of cement content has lower early strength, and faster carbonation velocity. To improve these problems and provide useful information for high volume fly ash concrete, the properties of concrete - those include slump, bleeding, setting time, compressive strength and carbonation depth etc. - which contained large amount of fly ash as a part of fine aggregate were investigated experimentally. According to test results, it was found that the compressive strength of the concrete increased in early age as well as in long term age with the increase of the fly ash content. And the carbonation depth of concrete using fly ash as a part of fine aggregate was lower than that of plain concrete(FA 0kg/ $\textrm{m}^3$).

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신 배전자동화 시스템의 하드웨어 및 소프트웨어 설계 (The hardware and software design of new distribution automation system)

  • 하복남;한용희;이중호;조남훈;임성일
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 C
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    • pp.1428-1430
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    • 1999
  • The New Distribution Automation System(NDAS) was composed of several equipments, computer system, communication system, feeder remote unit, switches and so on. In this paper, we introduce the conception of hardware and software design about Central Control System, the communication method and protocol in Feeder Remote Unit, the Automatic Switch, the operating software, consideration factors in the feeder automation(FA) and the system configuration of NDAS in power distribution test center.

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담비의 개디스템퍼 바이러스 자연 감염례 (Canine distemper virus infection in a marten)

  • 우계형;김재훈;진영화;이남일;황선욱;서일복;안동준
    • 한국수의병리학회지
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    • 제3권1호
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    • pp.61-64
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    • 1999
  • A dead marten(Martes melampus) showing cough, ataxia and convulsion of hind limb followed by seizures, was submitted for diagnosis to the Pathology Division of the National Veterinary Research and Quarantine Service. In the gross lesions, lung was congested and consolidated and meningeal blood vessels were mildly congested. Histopathologic findings were diffuse interstitial pneumonia and nonsuppurative meningoencephalitis with malacia of cerebral and cerebellar white matter. Eosinophilic inclusion bodies were observed in neurons and astrocytes and oligodendroglial cells of brain and transitional epithelium of kidney. Using FA test and PCR method, specific antigens of canine distemper virus were demonstrated in the brain.

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서비스 부문의 기술혁신목적별 정부 지원제도의 활용도 분석 연구 (Data Mining for the Effectiveness of Government Support Strategies for Technology Innovation in Service Sectors)

  • 황두현;김우진;손소영
    • 산업공학
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    • 제21권2호
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    • pp.237-246
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    • 2008
  • In today's competitive global environment, technological innovation is an important issue. Many countries are devising national level strategies to further strengthen industrial capacity in support of innovative companies. South Korea is no exception, and multiple strategies are in place to aid innovative development in the private sector. This study postulates that such national level strategies are applied differently depending on the innovation goal pursued by the service sector in Korea. We use data mining methods to test such research hypothesis. Factor analysis is used for clustering of various service companies, while association rule is used in finding the relationship per each cluster. The results show that national level strategies are underutilized and unequally distributed. This may be attributed to the disparity between the demand and needs of the private sector and the opinion of the government, which lead to underutilized and indistinguishable strategies.

한우송아지의 BVD바이러스 감염과 Aspergillus fumigatus의 복합감염 (Systemic Aspergillosis associated with bovine viral diarrhea virus infection in Korean native calves)

  • 진영화;김재훈;김대용;정순욱;문운경;조두연
    • 대한수의학회지
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    • 제45권1호
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    • pp.93-97
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    • 2005
  • Systemic aspergillosis were outbroken of 17 Korean native calves at livestock farm in Kyunggi province. Two 3 months old calves were died after having diarrhea, coughing, dyspnea, nasal discharge, and abdominal breathing. These calves were diagnosed of aspergillosis as multifocal to coalescing pyogranulomatous inflammation with intralesional aspergillus infiltration at liver, kidney, spleen, heart, lymph nodes, lungs, intestine and cerebrum. Aspergillus fumigatus was cultured from the affected tissues. And the small intestine was positive against bovine viral diarrhea (BVD) virus on FA test. We considered that the secondary fungal infections killed the calves after BVD virus infection primarily.

동결방지제에 의한 콘크리트의 스케일링 열화 (Scaling Deterioration of Concrete due to Deicing Salt)

  • 김규용;박찬규;김한준;손유신;이승훈
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2005년도 봄학술 발표회 논문집(II)
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    • pp.177-180
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    • 2005
  • Decing agent with chloride promote frost damage of concrete structure in winter period. From the safetyside, however, it is difficult to stop using chloride. Therefore, the durable concrete is required from now on. In this paper, long-term freezing and thawing test was carried out using the freezing water containing $CaCl_{2}$ to consider the concrete scaling according to the kind of binders, such as OPC, Flyash, Slag+Fa. and Slag As a result, it was found that the degree of scaling is different with containing slag being considered to prevent the penetration chloride ion and according to each binders.

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광물질 혼화재를 혼합한 초속경시멘트의 성능개선에 관한 실험적 연구 (An Experimental Study on the Enhanced Performance of Regulated Set Cement Using Mineral Admixtures)

  • 원종필;공태웅;박찬기;서정민;조용진;성상경
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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    • pp.325-328
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    • 2004
  • According to demand the increase of the rate of strength development for rapid constructions and repairs, many efforts have progressed to improve on performance of concrete. The use of regulated set cement helps make it possible to increase the rate of strength development. However it has some problems as like increasing its permeability and accelerate its long-term deterioration caused by internal and external factors. The purpose of this study is to improve the performance of regulated set cement, which mixed with the mineral admixtures. In this paper, setting time, compressive/flexural strength and chloride permeability of mortar according to the substitute ratio of SF, FA and BS in the range of $5\~20\%$ were conducted. Based on the test results, 5% substitute of silica fume for binder was showed good performance.

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석탄회 종류에 따른 석탄회를 대량 사용한 콘크리트의 내구특성에 관한 연구 (A Study on the Durabilities of High Volume Coal Ash Concrete by the Kinds of Coal Ash)

  • 최세진;김무한
    • 한국건축시공학회지
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    • 제9권3호
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    • pp.73-78
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    • 2009
  • Coal ash is a by-product of the combustion of pulverized coal, and much of this is dumped in landfills. The disposal of coal ash is one of the major issues for environmental problems. In this paper, the effects of the kinds and replacement ratio of coal ash on the durabilities of concrete mixtures are investigated. Fine aggregate was replaced with coal ash(fly ash and bottom ash) in five different ratios, of 0%, 10%, 20%, 35%, and 50% by volume. Test results indicated that the compressive strength increased with the increase in fly ash percentage. The loss of compressive strength of bottom ash concrete mixes after immersion in sulphuric acid solution was less than in the control mix(BA0). In addition, the carbonation depth of fly ash concrete mixes was lower than the control mix(FA0).

한국 남성의 고혈압에 대한 특징 선택 기반 위험 예측 (Feature selection-based Risk Prediction for Hypertension in Korean men)

  • 홍고르출;김미혜
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2021년도 춘계학술발표대회
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    • pp.323-325
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    • 2021
  • In this article, we have improved the prediction of hypertension detection using the feature selection method for the Korean national health data named by the KNHANES database. The study identified a variety of risk factors associated with chronic hypertension. The paper is divided into two modules. The first of these is a data pre-processing step that uses a factor analysis (FA) based feature selection method from the dataset. The next module applies a predictive analysis step to detect and predict hypertension risk prediction. In this study, we compare the mean standard error (MSE), F1-score, and area under the ROC curve (AUC) for each classification model. The test results show that the proposed FIFA-OE-NB algorithm has an MSE, F1-score, and AUC outcomes 0.259, 0.460, and 64.70%, respectively. These results demonstrate that the proposed FIFA-OE method outperforms other models for hypertension risk predictions.

저발열 결합재 및 CGS를 잔골재로 치환한 매스콘크리트의 수화열 해석 (Hydration Heat Analysis of Mass Concrete Replacement of Low Heat Binder and CGS with Fine Aggregate)

  • 한준희;임군수;최일경;윤치환;한민철;한천구
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2021년도 봄 학술논문 발표대회
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    • pp.235-236
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    • 2021
  • This study evaluated temperature distribution through adiabatic temperature rising test and hydration heat Analysis as a performance verification to utilize CGS as a hydration heat reduction material for mass concrete when replacing it with fine aggregate. According to the analysis, the temperature difference between the center and the surface was the highest at about 30℃, followed by the CGS 50% at 26℃ and the low heat combiner FA 30% at 23℃.

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