• Title/Summary/Keyword: AEA

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A Study on Discharge Statistics Quantities for Deterioration Diagnosis of Branch-type Tree (가지형 트리의 열화진단을 위한 방전통계량에 관한 연구)

  • Shin, S.K.;Kim, K.M.;Kim, T.Y.;Lee, D.J.;Park, C.O.;Kim, J.H.
    • Proceedings of the KIEE Conference
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    • 1999.07e
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    • pp.2345-2348
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    • 1999
  • Existing $\psi$-AEA-t (phase-AEA-time) characteristic in polymer materials for power cable is good in general deterioration characteristic according to time variation, but it is difficult to clearly distinguish from deterioration state and diagnosis of deterioration is not enough to some extent. This paper is interpreted AE discharge statistics quantities measuring phase-amplitude variation of acoustic emission characteristic obtained from treeing breakdown experiment. Besides it can know useful discharge statistics quantities (AE average inception phase/amplitude, AE average maximum phase/amplitude) about so many for diagnosis of treeing deterioration.

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Studies on the Preparation of Digestive Enzyme Tablest (IV) (소화효소제(消化酵素劑)의 제조(製造)에 관(關)한 연구(硏究) 제4보(第4報))

  • Kim, Yong-Bae;Kim, Whan-Hoe;Yi, Pyong-Kuk;Shin, Hyun-Jong
    • Journal of Pharmaceutical Investigation
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    • v.8 no.4
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    • pp.23-36
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    • 1978
  • Since the active center of digestive enzymetic preparations, while under storage, lose their activity and potency by the exposure to moisture, colorization, solidifying and other physical changes. It is more important than beautiful package form that protected packaging form from moisture to get a pharmaceutical safety preparations and to maintain a definite potency. Then, in order to get a desirable conditions of storage and packaging, we used shellac and $AEA^{\circledR}$ as a coating base, and blister package, foil and bottle container as a packaging material. Temperature were set on room temperature and $37^{\circ}C$, moisture was adjusted to 40% RH and 80 % RH as a accelerated conditions. Accelerated test was carried out 6 times. The results are as follows: 1) The effect of packaging conditions give great influence on the maintenace of the stable potency. 2) Best result was produced with bottle container package. 3) $AEA^{\circledR}$ is more useful than shellac as a coating base of prevention from moisture. 4) Absorption of moisture gave considerable effects on potency and it has a limited point. 5) Difference in potency between optimal and worst condition is 472 u/2T, and difference in effective period is about 44 months.

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A Parallel Adaptive Evolutionary Algorithm for Thermal Unit Commitment (병렬 적응 진화알고리즘을 이용한 발전기 기동정지계획에 관한 연구)

  • Kim, Hyung-Su;Cho, Duck-Hwan;Mun, Kyeong-Jun;Lee, Hwa-Seok;Park, June-Ho;Hwang, Gi-Hyun
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.55 no.9
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    • pp.365-375
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    • 2006
  • This paper is presented by the application of parallel adaptive evolutionary algorithm(PAEA) to search an optimal solution of a thermal unit commitment problem. The adaptive evolutionary algorithm(AEA) takes the merits of both a genetic algorithm(GA) and an evolution strategy(ES) in an adaptive manner to use the global search capability of GA and the local search capability of ES. To reduce the execution time of AEA, the developed algorithm is implemented on an parallel computer which is composed of 16 processors. To handle the constraints efficiently and to apply to Parallel adaptive evolutionary algorithm(PAEA), the states of thermal unit are represented by means of real-valued strings that display continuous terms of on/off state of generating units and are involved in their minimum up and down time constraints. And the violation of other constraints are handled by repairing operator. The procedure is applied to the $10{\sim}100$ thermal unit systems, and the results show capabilities of the PAEA.

A Study On the Diagnosis Breakdown Using Fractal Characteristics and the Method of Acoustic Emission in Low Density Polyethylene (프랙탈 특성과 음향방출 계측법을 이용한 LDPE 시료에서의 트리잉 파괴진단에 관한 연구)

  • Yoon, H.J.;Park, J.J.;Shin, S.J.;Choi, J.K.;Kim, S.H.;Kim, J.H.
    • Proceedings of the KIEE Conference
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    • 1997.07e
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    • pp.1758-1760
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    • 1997
  • Automatic detection system to detect acoustic emission pulse and fractal dimension were developed, to observe tree deterioration phenomena in LDPE. The purpose of our work are to use acoustic emission system and fractal dimension and to investigate the treeing phenomena in polymeric insulation under applied AC voltage 11[kV] with an artificial needle-shaped void(1.5[mm]) using the above system. We analyzed and phase angle-acoustic emission pulse amplitude-deterioration time ($\Phi$-AEA-t) pattern and phase angle-acoustic emission pulse number-deterioration time($\Phi$-AEN-t) pattern using statistical operators such as skewness, fractal dimension. In this paper show that the correlation of $\Phi$-AEA-t, $\Phi$-AEN-t, fractal dimension using regression analysis by the method of least squares can be used to predict the breakdown just before the breakdown occurs.

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A Study on Optimized Disaster Broadcasting Service for Vulnerable Populations based on ATSC 3.0 Standards (ATSC 3.0 기반 재난약자 맞춤형 재난방송서비스에 대한 연구)

  • Kim, Nayeon;Hyun, Eunhee;Bae, Byungjun
    • Journal of Broadcast Engineering
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    • v.24 no.6
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    • pp.928-938
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    • 2019
  • Republic of Korea has established 'Transmission and Reception for Terrestrial UHDTV Broadcasting Service' standard based on ATSC 3.0, the next-generation broadcasting standard in North America and is now providing commercial services. Republic of Korea has been studying terrestrial UHDTV based disaster broadcasting service using the ATSC 3.0 AEA system's technology since 2018. ATSC 3.0 has established a standard for expanding disaster broadcasting services, which were used to be simple push-type text message broadcasting, by introducing bidirectional and rich-media transporting mechanisms. However, the disaster information is still focused on the general public, and disaster broadcasting service including detailed information for the vulnerable are still insufficient. In this paper, we proposed the optimized disaster broadcasting service for vulnerable populations based on ATSC 3.0 after defined the disaster vulnerable populations as the target of the service. And we defined the extension element of disaster broadcasting message for service provision. The proposed service can be an effective means to increase the possibility of disaster information reception and evacuation to vulnerable populations. In addition, it is expected to be used as a basic research for development of diverse and effective advanced services for vulnerable populations through linkage with existing disaster alerting and countermeasures studies.

Studies on Water Vapor Absorption through Hard Gelatin Capsules (경(硬)갚셀제(劑)의 흡습(吸濕)에 관(關)한 연구(硏究))

  • Park, Joung-Hoon
    • Journal of Pharmaceutical Investigation
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    • v.3 no.3
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    • pp.16-19
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    • 1973
  • Stability is impaired in capsules in which there is a transfer of water vapor from capsule to the contents of the capsules. The water vapor transfer between AEA-coated capsules and corn starch, magnesium trisilicate in the closed container was examined. Experimental eguilibrium relative humidity after water vapor transfer and estimated values calculated from a formula of these substances were in close agreement with each other.

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제12회 한국원산/원자력학회 연차대회

  • Korea Radioisotope Association
    • 동위원소뉴스
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    • no.4 s.4
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    • pp.7-8
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    • 1997
  • 제12회 한국원산/원자력학회 연차대회가 4월 3일(목)부터 2일간 서울 르네상스 호텔에서 열렸다. 이번 대회에는 미국, 영국, 일본, 캐나다 등 세계 13개국 및 IAEA에서 총 6백여명의 원자력 전문가가 참가했다. 이번 회의의 주제는 "원자력의 지속적인 성장과 환경보전의 길"로서 56명의 전문가들이 원전 연료의 개발, 원전의 운전성능과 안전성향상, 신형로의 개발, 방사성폐기물의 관리 등 업계의 현안에 대해 진지한 토론을 벌였다. 첫날 회의에서는 정수교 대한핵의학회 이사장, 빅토르 미하일로비치 모로코프 국제원자력기구(IAEA)사무차장, 브라이언 에어 영국 AEA테크놀로지 부회장, 버트란드 바레 프랑스원자력학회 회장 등의 특강의 내용을 요약한다.

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Groundwater Flow Characterization in the Vicinity of the Underground Caverns by Groundwater Level Changes (지하수위 변화에 따른 지하공동 주변의 지하수 유동특성 해석)

  • 강재기;양형식;김경수;김천수
    • Tunnel and Underground Space
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    • v.13 no.6
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    • pp.465-475
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    • 2003
  • Groundwater inflow into the caverns constructed in fractured rock mass was simulated by numerical modeling, NAPSAC (DFN, discrete fracture network model) and NAMMU (CPM, continuous porous media model), a finite-element software package for groundwater flow in 3D fractured media developed by AEA Technology, UK. The input parameters for modeling were determined on surface fracture survey, core logging and single hole hydraulic test data. In order to predict the groundwater inflow more accurately, the anisotropic hydraulic conductivity was considered. The anisotropic hydraulic conductivities were calculated from the fracture network properties. With a minor adjustment during model calibration, the numerical modeling is able to reproduce reasonably groundwater inflows into cavern and the travel length and times to the ground surface along the flow paths in the normal, dry and rainy seasons.

Effect of Steel Fiber Addition on the Mechanical Properties and Durability of High-Flowable Retaining Wall Material (고유동 흙막이 벽체 재료의 역학적 성능 및 내구성에 대한 강섬유 혼입률의 영향)

  • Donggyu Kim;Seungtae Lee
    • Journal of the Korean GEO-environmental Society
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    • v.24 no.6
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    • pp.13-20
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    • 2023
  • This paper is aimed to evaluate the mechanical properties and durability of high-flowable retaining wall material (RWM) with different levels of steel fiber (SF) content. To produce the specimens of RWM, some chemical agents such as superplasticizer (SP), air-entrained agent (AEA) and viscosity modifying agent (VMA) were added in the fresh RWM. The compressive and split tensile strength measurements were performed on the hardened RWM specimens at the predetermined periods. Additionally, surface electric resistivity and absorption tests according to ASTM standards were carried out to examine mechanical properties of RWM mixes. The durable performances such as chloride ions penetrability and freezing-thawing resistance of RWM mixes were experimentally investigated. As resutls, it was found that the performance of RWM mix with SF were much better than that without SF, especially at the 2% addition of SF. Thus, it is noted that the proper addition of SF in the RWM mix may have a beneficial effect to improve mechanical properties and durability of RWM mixes.