• 제목/요약/키워드: Utilization history

검색결과 279건 처리시간 0.021초

DESIGN OF LSDS FOR ISOTOPIC FISSILE ASSAY IN SPENT FUEL

  • Lee, Yongdeok;Park, Chang Je;Kim, Ho-Dong;Song, Kee Chan
    • Nuclear Engineering and Technology
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    • 제45권7호
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    • pp.921-928
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    • 2013
  • A future nuclear energy system is being developed at Korea Atomic Energy Research Institute (KAERI), the system involves a Sodium Fast Reactor (SFR) linked with the pyro-process. The pyro-process produces a source material to fabricate a SFR fuel rod. Therefore, an isotopic fissile content assay is very important for fuel rod safety and SFR economics. A new technology for an analysis of isotopic fissile content has been proposed using a lead slowing down spectrometer (LSDS). The new technology has several features for a fissile analysis from spent fuel: direct isotopic fissile assay, no background interference, and no requirement from burnup history information. Several calculations were done on the designed spectrometer geometry: detection sensitivity, neutron energy spectrum analysis, neutron fission characteristics, self shielding analysis, and neutron production mechanism. The spectrum was well organized even at low neutron energy and the threshold fission chamber was a proper choice to get prompt fast fission neutrons. The characteristic fission signature was obtained in slowing down neutron energy from each fissile isotope. Another application of LSDS is for an optimum design of the spent fuel storage, maximization of the burnup credit and provision of the burnup code correction factor. Additionally, an isotopic fissile content assay will contribute to an increase in transparency and credibility for the utilization of spent fuel nuclear material, as internationally demanded.

조선후기 사의당의 위치와 건축적 특징에 대한 추론 (A Study on the Location and Architectural Features of Sauidang in the Late Joseon Period)

  • 박혜정;조재모
    • 건축역사연구
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    • 제26권2호
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    • pp.53-66
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    • 2017
  • The purpose of this study is to estimate the location and space configuration of Sauidang(四宜堂), which is a house in the late Joseon period. Sauidang was built by Hong Man-hoe(洪萬恢), the last son of Princess Jeongmyeong(貞明公主), was used as a house for Pungsan Hong clan(豊山 洪氏) for approximately 150 years, and is now defunct. However, the existence was estimated through Sauidang-ji("四宜堂志") compiled by Gwan-am Hong Gyeong-mo(冠巖 洪敬謨) in 1824. Based on the mention that "Sauidang was located in Hundo-bang(薰陶坊) of Ihyeon-dong(梨峴洞)" and the literature referring to "the site of Myeongryegung Palace(明禮宮)", this study estimated the location of Sauidang. Maps and photographic data in the modern age enabled us to examine the utilization cases of medium- and large-sized lots by examining the correlation with the current Embassy of the People's Republic of China in the Republic of Korea. In addition, it was possible to estimate the spatial configuration of Sauidang with a focus on words to clarify the detailed explanation of Sauidang mentioned in the literature and spatial relationship.

구 동양척식주식회사 부산지점(부산근대역사관)의 복합구조 특성 (The Composite Structure Characteristics of the Formerly the Busan Branch of Toyo Takushoku Co.(Busan Modern History Museum))

  • 안재철
    • 대한건축학회논문집:계획계
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    • 제35권10호
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    • pp.63-70
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    • 2019
  • The Busan branch of the former Toyo Takushoku Co. carried out the same business as a bank at the time of construction. This required an open space of long-span, which had no pillars, on the first floor where many customers frequently visited. In addition, an office space is required in the upper part, and a column is arranged so as to place a corridor in the center. It was designed with modern complex structures for space utilization and structural adaptation. As a result, scientific structural calculations of the modern era began and various structural technologies were introduced, the rationalization and value of various spatial characteristics and their structural design were analyzed from a technical historical perspective in the structure requiring long-span space. The Busan branch of the former Toyo Takushoku Co. is a complex structure with three structures. It is highly valuable as a building that tried to design its structure in a variety of spaces through calculation and introduction of new technology based on the principle of force in modern times.

이미지 생성 및 지도학습을 통한 전통 건축 도면 노이즈 제거 (Denoising Traditional Architectural Drawings with Image Generation and Supervised Learning)

  • 최낙관;이용식;이승재;양승준
    • 건축역사연구
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    • 제31권1호
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    • pp.41-50
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    • 2022
  • Traditional wooden buildings deform over time and are vulnerable to fire or earthquakes. Therefore, traditional wooden buildings require continuous management and repair, and securing architectural drawings is essential for repair and restoration. Unlike modernized CAD drawings, traditional wooden building drawings scan and store hand-drawn drawings, and in this process, many noise is included due to damage to the drawing itself. These drawings are digitized, but their utilization is poor due to noise. Difficulties in systematic management of traditional wooden buildings are increasing. Noise removal by existing algorithms has limited drawings that can be applied according to noise characteristics and the performance is not uniform. This study presents deep artificial neural network based noised reduction for architectural drawings. Front/side elevation drawings, floor plans, detail drawings of Korean wooden treasure buildings were considered. First, the noise properties of the architectural drawings were learned with both a cycle generative model and heuristic image fusion methods. Consequently, a noise reduction network was trained through supervised learning using training sets prepared using the noise models. The proposed method provided effective removal of noise without deteriorating fine lines in the architectural drawings and it showed good performance for various noise types.

건축유산의 디지털 기술 활용에 관한 국제 연구동향 분석: CIPA2023 국제심포지엄 사례를 중심으로 (Analysis of International Research Trends in the Utilization of Digital Technologies for Architectural Heritage: A Case Study of the CIPA2023 International Symposium)

  • 강혜리;이종욱
    • 건축역사연구
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    • 제32권6호
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    • pp.63-75
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    • 2023
  • Based on my attendance at the CIPA International Symposium(CIPA2023) organized by the International Scientific Committee on Heritage Documentation(ICOMOS), this paper explored research cases applying digital technologies, including BIM, to architectural heritage. The researches presented at this symposium were categorized into specific areas: data acquisition, data management, data sharing&experience. Through this classification, an analysis of research cases in architectural heritage utilizing digital technology was conducted. By categorizing the 43 academic papers from the CIPA2023 based on research themes, trends in the digital architecture field were analyzed, providing insights into future research directions for the digital acquisition, management, sharing, and experiential aspects of Korean architectural heritage. In conclusion, it is deemed necessary to reference and supplement the methodologies, including algorithms, workflows, and approaches developed in each study, to effectively apply methodologies suitable for the characteristics of Korean architectural heritage and its data.

Utilization of deep learning-based metamodel for probabilistic seismic damage analysis of railway bridges considering the geometric variation

  • Xi Song;Chunhee Cho;Joonam Park
    • Earthquakes and Structures
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    • 제25권6호
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    • pp.469-479
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    • 2023
  • A probabilistic seismic damage analysis is an essential procedure to identify seismically vulnerable structures, prioritize the seismic retrofit, and ultimately minimize the overall seismic risk. To assess the seismic risk of multiple structures within a region, a large number of nonlinear time-history structural analyses must be conducted and studied. As a result, each assessment requires high computing resources. To overcome this limitation, we explore a deep learning-based metamodel to enable the prediction of the mean and the standard deviation of the seismic damage distribution of track-on steel-plate girder railway bridges in Korea considering the geometric variation. For machine learning training, nonlinear dynamic time-history analyses are performed to generate 800 high-fidelity datasets on the seismic response. Through intensive trial and error, the study is concentrated on developing an optimal machine learning architecture with the pre-identified variables of the physical configuration of the bridge. Additionally, the prediction performance of the proposed method is compared with a previous, well-defined, response surface model. Finally, the statistical testing results indicate that the overall performance of the deep-learning model is improved compared to the response surface model, as its errors are reduced by as much as 61%. In conclusion, the model proposed in this study can be effectively deployed for the seismic fragility and risk assessment of a region with a large number of structures.

학성이씨 파종가 울산 근재공고택의 건축적 특징에 관한 연구 -상부가구의 유형 분석과 처마 공간 구성을 중심으로- (A Study on the Architectural Characteristics of Ul-san Geun-jae-gong Historic House of Hak-seong Lee Family -Focused on the Typological Analysis of the Upper Structure and the Composition of the Eaves space)

  • 배창현
    • 건축역사연구
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    • 제32권5호
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    • pp.51-58
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    • 2023
  • This study was conducted to examine the architectural characteristics of Hak-seong Lee Family's Geun-jae-gong Historic House located in Seok-cheon-ri, Ung-chon-myeon, Ulju-gun, Ulsan. The house is said to have been rebuilt in the early 20th century after it was built in the 18th century, and now there are nine buildings left, including the An-chae, Sa-rang-chae, Sa-dang, storehouses and etc. This house is a large-scale house that is difficult to find similar cases in near region. The division of areas on each building is clear, and it is evaluated that it retains the typical characteristics of the head family in the late Joseon Dynasty in terms of its overall size and layout. In addition, the current wooden structure, which is said to have been rebuilt in the early 20th century, shows the composition method and space utilization method of the 3-Dori type upper structure, which have become more diverse since the late Joseon Dynasty. This has not been dealt with in the previous survey, and should be considered in detail through this paper.

A Resource Reduction Scheme with Low Migration Frequency for Virtual Machines on a Cloud Cluster

  • Kim, Changhyeon;Lee, Wonjoo;Jeon, Changho
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제7권6호
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    • pp.1398-1417
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    • 2013
  • A method is proposed to reduce excess resources from a virtual machine(VM) while avoiding subsequent migrations for a computer cluster that provides cloud service. The proposed scheme cuts down on the resources of a VM based on the probability that migration may occur after a reduction. First, it finds a VM that can be scaled down by analyzing the history of the resource usage. Then, the migration probability is calculated as a function of the VM resource usage trend and the trend error. Finally, the amount of resources needed to eliminate from an underutilized VM is determined such that the migration probability after the resource reduction is less than or equal to an acceptable migration probability. The acceptable migration probability, to be set by the cloud service provider, is a criterion to assign a weight to the resource reduction either to prevent VM migrations or to enhance VM utilization. The results of simulation show that the proposed scheme lowers migration frequency by 31.6~60.8% depending on the consistency of resource demand while losing VM utilization by 9.1~21.5% compared to other known approaches, such as the static and the prediction-based methods. It is also verified that the proposed scheme extends the elapsed time before the first occurrence of migration after resource reduction 1.1~2.3-fold. In addition, changes in migration frequency and VM utilization are analyzed with varying acceptable migration probabilities and the consistency of resource demand patterns. It is expected that the analysis results can help service providers choose a right value of the acceptable migration probability under various environments having different migration costs and operational costs.

싱가포르 지하공간 개발의 현황 및 이슈 (Status and Issues for Underground Space Development in Singapore)

  • 이희석
    • 터널과지하공간
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    • 제28권4호
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    • pp.304-324
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    • 2018
  • 싱가포르는 국토가 부족한 도시 국가의 특성으로 인해 지하 공간의 개발 및 활용을 정부차원에서 전 국가적으로 강력하게 추진하고 있다. 특히 지하철과 지하 도로와 같은 일반 얕은 심도의 지하공간의 활용뿐 아니라 대규모 지하공간 사업으로서 암반 내 지하 탄약 저장고 프로젝트를 성공적으로 마친 이후, 두번째 대규모 암반 지하공간 프로젝트인 Jurong Rock Cavern을 얼마전 준공한 바 있다. 본 논문에서는 싱가포르의 지질 분석을 통해 암반 지하공간 개발의 조건에 대해 평가한 후, 싱가포르의 다양한 지하공간 개발의 역사와 현황을 살펴본다. 지하 저수지, 지하 자동화 물류 시스템 및 물류 저장 창고 등 정부 차원에서 향후 추진이 예상되는 창의적인 암반내 주요 지하공간 관련 계획 및 기술적인 이슈들에 대해서 소개한다. 또한 이러한 대규모 암반 지하공간 개발에 관련된 향후 문제와 이슈들에 대해서 논의한다. 싱가포르의 이러한 적극적인 지하공간 개발 움직임은 또한 암반공학 및 업계에 향후 많은 기회와 과제를 줄 것으로 기대된다.

Interactions Between MTHFR C677T - A1298C Variants and Folic Acid Deficiency Affect Breast Cancer Risk in a Chinese Population

  • Wu, Xia-Yu;Ni, Juan;Xu, Wei-Jiang;Zhou, Tao;Wang, Xu
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권5호
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    • pp.2199-2206
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    • 2012
  • Background: Our objective was to evaluate the MTHFR C677T-A1298C polymorphisms in patients with breast cancer and in individuals with no history of cancer, to compare the levels of genetic damage and apoptosis under folic acid (FA) deficiency between patients and controls, and to assess associations with breast cancer. Methods: Genetic damage was marked by micronucleated binucleated cells (MNBN) and apoptosis was estimated by cytokinesis-block micronucleus assay (CBMN). PCR-RFLP molecular analysis was carried out. Results: The results showed significant associations between the MTHFR 677TT or the combined MTHFR C677T-A1298C and breast cancer risk (OR = 2.51, CI = 0.85 to 7.37, p = 0.08; OR = 4.11, CI = 0.78 to 21.8, p < 0.001). The MNBN from the combined MTHFR C677T-A1298C was higher and the apoptosis was lower than that of the single variants (p < 0.05). At 15 to 60 nmol/L FA, the MNBN in cases with the TTAC genotype was higher than controls (p < 0.05), whereas no significant difference in apoptosis was found between the cases and controls after excluding the genetic background. Conclusions: Associations between the combined MTHFR C677T-A1298C polymorphism and breast cancer are possible from this study. A dose of 120 nmol/L FA could enhance apoptosis in cases with MTHFR C677T-A1298C. Breast cancer individuals with the TTAC genotype may be more sensitive to the genotoxic effects of FA deficiency than controls.