• 제목/요약/키워드: term functions

검색결과 796건 처리시간 0.032초

고준위폐기물처분장 완충재물질로서 팽윤성 점토의 장기건전성과 주요 고려사항 (Longevity Issues in Swelling Clay as a Buffer Material for a HLW Repository)

  • 이재완;조원진
    • 방사성폐기물학회지
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    • 제6권1호
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    • pp.55-63
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    • 2008
  • 고준위폐기물처분장의 완충재 물질로 사용되는 팽윤성 점토는 방벽재로서 그 기능을 제대로 발휘하기 위해 오랫동안 물리 화학적으로 안정해야 한다. 팽윤성 점토의 장기건전성 관련인 자들을 검토하고, 처분장 성능에 대한 각 인자의 중요성을 평가하였다. 검토결과, 붕괴 열에 의한 온도상승, 지하수 화학, 콘크리트에 의한 pH 증가, 유기물과 미생물, 방사선 조사 및 기계적 교란은 완충재물질로서 팽윤성 점토의 장기건전성에 중요한 인자임을 확인하였다. 본 연구는 고준위폐기물 처분장에서 팽윤성 점토의 완충재 설계를 위한 기초자료로 유용하게 활용될 것이다.

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부산항부두관리공사의 개편방안에 대한 연구 (A Study on Reorganization Plan of Busanport Pier Management Corporation)

  • 김상구;강윤호
    • 해양환경안전학회:학술대회논문집
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    • 해양환경안전학회 2009년도 춘계학술발표회
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    • pp.95-103
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    • 2009
  • 본 연구는 현재 통폐합 위기에 처한 부산항부두관리공시(이하 부공이라 함)의 담당업무인 축제여객터미널, 크루즈터미널, 연안여객터미널 등 항만시설 관리기능의 합리적 민간위탁 방안을 모색하고자 하였다. 이러한 연구목적을 달성하기 위하여 이들 항만시설물의 위탁기간, 위탁의 당위성(장점), 위탁범위와 위탁비용 등을 탐색하였다. 연구의 결과, 부공 자체를 주식회사화 하여 민간화시키는 방안이 최선의 대안으로 도출되었다.

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SaaS(Software as a Service) 기반 지방유적도시 구조물 유지관리계측 통합모니터링시스템 구현 (Implementation of an Integrated Monitoring System for Constructional Structures Based on SaaS in Traditional Towns with Local Heritage)

  • 민병원;오용선
    • 한국콘텐츠학회:학술대회논문집
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    • 한국콘텐츠학회 2015년도 춘계 종합학술대회 논문집
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    • pp.15-16
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    • 2015
  • Measuring sensor, equipment, ICT facilities and their software have relatively short life time comparing to constructional structure so that we should exchange or fix them continuously in the process of maintenance and management. In this paper, we propose a novel design of integrated maintenance, management, and measuring monitoring system applying the concept of mobile cloud. For the sake of disaster prevention for constructional structures such as bridge, tunnel, and other traditional buildings in the village of local heritage, we analyze status of these structures in the long term or short term period as well as disaster situations. Collecting data based on mobile cloud and analyzing future expectations based on probabilistic and statistical techniques, we implement our integrated monitoring system for constructional structures to solve these existing problems. Final results of this design and implementation are basically applied to the monitoring system for more than 10,000 structures spread over national land in Korea. In addition, we can specifically apply the monitoring system presented here to a bridge of timber structure in Asan Oeam Village and a traditional house in Andong Hahoe Village to watch them from possible disasters. Total procedure of system design and implementation as well as development of the platform LinkSaaS and application services of monitoring functions implemented on the platform. We prove a good performance of our system by fulfilling TTA authentication test, web accommodation test, and operation test using real measuring data.

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영상 복원을 위한 자기 정규화 방법 (Self-Regularization Method for Image Restoration)

  • 류재흥
    • 한국전자통신학회논문지
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    • 제11권1호
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    • pp.45-52
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    • 2016
  • 본 논문은 영상 복원 문제에 대한 정규화 모수를 찾는 새로운 방법을 제시한다. 위너 필터(Wiener filter)는 원본 영상과 잡음의 파워 스펙트럼 등의 사전 정보를 요구한다. 제약된 최소자승 복원 역시 노이즈 수준에 대한 지식을 요구한다. 사전 정보가 없으면 티코노프(Tikhonov) 정규화 모수를 선택하기 위한 일반화된 교차 검증법이나 L자형 곡선 검정 등의 별도의 최적화 함수가 필요하다. 본 논문에서는 주파수 영역에서 선형 시스템의 바이어스 항목과 티코노프 정규화 시스템의 평활화 항목을 연결하는 자기 정규화 방법을 제안하고 영상 복원 문제에 적용한다. 실험결과는 제안하는 방법의 효능을 보여준다.

도로자산관리를 위한 포장종합평가지수의 속성과 변화과정의 모델링 (Internal Property and Stochastic Deterioration Modeling of Total Pavement Condition Index for Transportation Asset Management)

  • 한대석;도명식;김부일
    • 한국도로학회논문집
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    • 제19권5호
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    • pp.1-11
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    • 2017
  • PURPOSES : This study is aimed at development of a stochastic pavement deterioration forecasting model using National Highway Pavement Condition Index (NHPCI) to support infrastructure asset management. Using this model, the deterioration process regarding life expectancy, deterioration speed change, and reliability were estimated. METHODS : Eight years of Long-Term Pavement Performance (LTPP) data fused with traffic loads (Equivalent Single Axle Loads; ESAL) and structural capacity (Structural Number of Pavement; SNP) were used for the deterioration modeling. As an ideal stochastic model for asset management, Bayesian Markov multi-state exponential hazard model was introduced. RESULTS:The interval of NHPCI was empirically distributed from 8 to 2, and the estimation functions of individual condition indices (crack, rutting, and IRI) in conjunction with the NHPCI index were suggested. The derived deterioration curve shows that life expectancies for the preventive maintenance level was 8.34 years. The general life expectancy was 12.77 years and located in the statistical interval of 11.10-15.58 years at a 95.5% reliability level. CONCLUSIONS : This study originates and contributes to suggesting a simple way to develop a pavement deterioration model using the total condition index that considers road user satisfaction. A definition for level of service system and the corresponding life expectancies are useful for building long-term maintenance plan, especially in Life Cycle Cost Analysis (LCCA) work.

Developmental Role of Chamber of Commerce and Industries in Bangladesh: A Case Study of Sylhet Chamber of Commerce and Industries

  • Bhuiyan, Bashir Ahmed;Latif, Abdul
    • 아태비즈니스연구
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    • 제2권1호
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    • pp.1-22
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    • 2011
  • Chamber of commerce and industry plays important role for development of business community and creating vibrant competition. Present paper compares chambers operations in Bangladesh, especially, Sylhet Chamber of Commerce and Industry(SCCI) by reviewing global models of chambers practices. The study identifies important gaps between international standards and Bangladesh practices. Mostly practiced chambers model in the world are: Continental Model, Anglo-Saxon Model and Mixed model or Asian model. Like other Asian countries, chambers in Bangladesh including SCCI, have been following Mixed Model. The empirical study found that SCCI is performing different developmental functions like accumulating members, collecting revenue, fulfilling corporate social responsibility and providing business development services to its members and business community. The notable constraining factors of SCCI operations are: short term orientation in assembling members, limited functional activities, lack of creative endeavors in diversifying services, linkage between SCCI and academic institutions, poor research involvement etc. The necessary suggestions for improvement of chambers performance include adoption of creative measures in various operations, providing training to the members, assisting entrepreneurs in obtaining industrial finance and extending support in the establishment of specialized industrial zone for attaining long term developmental objectives.

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노년층의 말소리 지각 능력 및 관련 인지적 변인 (Speech perception difficulties and their associated cognitive functions in older adults)

  • 이수정;김향희
    • 말소리와 음성과학
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    • 제8권1호
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    • pp.63-69
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    • 2016
  • The aims of the present study are two-fold: 1) to explore differences on speech perception between younger and older adults according to noise conditions; and 2) to investigate which cognitive domains are correlated with speech perception. Data were acquired from 15 younger adults and 15 older adults. Sentence recognition test was conducted in four noise conditions(i.e., in-quiet, +5 dB SNR, 0 dB SNR, -5 dB SNR). All participants completed auditory and cognitive assessment. Upon controlling for hearing thresholds, the older group revealed significantly poorer performance compared to the younger adults only under the high noise condition at -5 dB SNR. For older group, performance on Seoul Verbal Learning Test(immediate recall) was significantly correlated with speech perception performance, upon controlling for hearing thresholds. In older adults, working memory and verbal short-term memory are the best predictors of speech-in-noise perception. The current study suggests that consideration of cognitive function for older adults in speech perception assessment is necessary due to its adverse effect on speech perception under background noise.

세포내인자로서의 정교한 기능을 하는 molecular chaperone (Molecular chaperone as a sophisticated intracellular membership)

  • 권오유;송민호
    • 생명과학회지
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    • 제8권2호
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    • pp.223-233
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    • 1998
  • Molecular chaperone의 발견은 생명과학자들에게 살아있는 세포 내에서 어떻게 생체활성단백질이 만들어지고 유지되는지에 대한 자극과 함께 그것을 증명하기 위한 실험동기를 부여하였다. 초기에는 Molecular chaperone이 nucleosomes의 assembly에 관여하는 단백질을 설명하기 위하여 사용되었으나, 지금은 기본적인 세포생리기능의 하나인 단백질의 folding과 assembly를 돕는 assistant protein으로 주로 사용된다. 단백질합성 뿐만 아니라 단백질수송, oligomeric structure의 assembly와 disassembly, heat shock을 포함한 각종 내, 외부스트래스에 의해서 변성된 단백질의 세로내분화와 회복에도 Molecular chaperone이 관여하고 있다. 그러나 아직까지는 Molecular chaperone들의 3차구조와 그들간의 상호작용에 관한 정보가 부족하여 크게 진전되지 못하고 있지만, 많은 연구자에 의한 정보축적으로 인하여 빠른 시일 내에 Molecular chaperone에 세포내역할이 분명하게밝혀질 것이다.

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A Combined Procedure of RSM and LHS for Uncertainty Analyses of CsI Release Fraction Under a Hypothetical Severe Accident Sequence of Station Blackout at Younggwang Nuclear Power Plant Using MAAP3.0B Code

  • Han, Seok-Jung;Tak, Nam-Il;Chun, Moon-Hyun
    • Nuclear Engineering and Technology
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    • 제28권6호
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    • pp.507-521
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    • 1996
  • Quantification of uncertainties in the source term estimations by a large computer code, such as MELCOR and MAAP, is an essential process of the current Probabilistic safety assessment. The main objective of the present study is to investigate the applicability of a combined procedure of the response surface method (RSM) based on input determined from a statistical design and the Latin hypercube sampling (LHS) technique for the uncertainty analysis of CsI release fractions under a Hypothetical severe accident sequence of a station blackout at Younggwang nuclear power plant using MAAP3. OB code as a benchmark problem. On the basis of the results obtained in the present work, the RSM is recommended to be used as a principal tool for an overall uncertainty analysis in source term quantifications, while using the LHS in the calculations of standardized regression coefficients (SRC) and standardized rank regression coefficient (SRRC) to determine the subset of the most important input parameters in the final screening step and to check the cumulative distribution functions obtained by RSM. Verification of the response surface model for its sufficient accuracy is a prerequisite for the reliability of the final results that can be obtained by the combined procedure proposed in the present work.

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The Impact of Contingency Factors on Management Accounting Practices in Vietnam

  • PHAM, Duc Hieu;DAO, Thi Huong;BUI, Tien Dung
    • The Journal of Asian Finance, Economics and Business
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    • 제7권8호
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    • pp.77-85
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    • 2020
  • The aim of this study is two-fold. Firstly, it attempts to assess the level of management accounting practices (MAPs) in manufacturing companies in Vietnam. Secondly, it purports to explore the impact of potential contingency factors on the current level of MAPs in the sample of studied companies from the industrial sector in Vietnam. The study examines the hypotheses that MAPs in Vietnamese manufacturing firms are affected by a range of contingent variables. A quantitative research was conducted by sending questionnaires to the target respondents that comprise both accountants and managers in 160 manufacturing enterprises in the north of Vietnam. The first main findings from the study reveal that MAPs in Vietnam are mainly traditional rather than contemporary ones, and oriented toward the short-term rather than the long-term. The second main research findings resulted from multiple regression model show that MAPs in Vietnam are significantly affected by company size, commitment of directors, advanced manufacturing technology, and distinct number of products. However, no significant associations are found between MAPs and intensity of competition from the emerging market as hypothesized in this study. Research findings are bases for recommendations to promote the application of contemporary practices and enhance management accounting functions in manufacturing companies in Vietnam.