• 제목/요약/키워드: Demand Variable

검색결과 572건 처리시간 0.031초

Probabilistic analysis of spectral displacement by NSA and NDA

  • Devandiran, P.;Kamatchi, P.;Rao, K. Balaji;Ravisankar, K.;Iyer, Nagesh R.
    • Earthquakes and Structures
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    • 제5권4호
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    • pp.439-459
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    • 2013
  • Main objective of the present study is to determine the statistical properties and suitable probability distribution functions of spectral displacements from nonlinear static and nonlinear dynamic analysis within the frame work of Monte Carlo simulation for typical low rise and high rise RC framed buildings located in zone III and zone V and designed as per Indian seismic codes. Probabilistic analysis of spectral displacement is useful for strength assessment and loss estimation. To the author's knowledge, no study is reported in literature on comparison of spectral displacement including the uncertainties in capacity and demand in Indian context. In the present study, uncertainties in capacity of the building is modeled by choosing cross sectional dimensions of beams and columns, density and compressive strength of concrete, yield strength and elastic modulus of steel and, live load as random variables. Uncertainty in demand is modeled by choosing peak ground acceleration (PGA) as a random variable. Nonlinear static analysis (NSA) and nonlinear dynamic analysis (NDA) are carried out for typical low rise and high rise reinforced concrete framed buildings using IDARC 2D computer program with the random sample input parameters. Statistical properties are obtained for spectral displacements corresponding to performance point from NSA and maximum absolute roof displacement from NDA and suitable probability distribution functions viz., normal, Weibull, lognormal are examined for goodness-of-fit. From the hypothesis test for goodness-of-fit, lognormal function is found to be suitable to represent the statistical variation of spectral displacement obtained from NSA and NDA.

직업적 특성, 사회심리적 스트레스 및 호모시스테인의 관련성 (The Association between Job Characteristics, Psychosocial Distress and Homocysteine)

  • 차봉석;고상백;장세진
    • Journal of Preventive Medicine and Public Health
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    • 제31권4호
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    • pp.719-727
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    • 1998
  • This study was carried out to assess the relationship between jobstrain, psychosocial distress and homocysteine. The study design was cross-sectional, and included 152 industrial workers in middle sized city. A self-adminstered questionnaire measured general characteristic, job strain and psychosocial distress. Blood was drawn into EDTA tube, and total plasma homocysteine was measured by HPLC. Homocysteine in the high job demand group was sagnificantly higher than that in the low job demand. Cholesterol in the high job control group was significantly higher than that in the low job control. Homocysteine was significantly higher in the high job strain group than that in the other group. Folate and vitamin B12 showed a significantly negative correlation with homocysteine. Multiple regression analysis was used to determine whether the psychosocial distress and other variable contributed to explaining the homocysteine. Stress correlates with the homocysteine.

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물류계획을 위한 지역유형 추정 (Estimation of Area Type for Logistics Planning)

  • 윤성순
    • 대한교통학회지
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    • 제23권5호
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    • pp.65-71
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    • 2005
  • 지역유형(area type)은 물류수요의 잠재력(potential)과 밀접한 관련이 있다. 물류계획분야에서 지역유형 변수는 특히 발생모형(generation model)에서 물류유입(freight attraction)을 설명하는 모형변수로, 또한 수송수단선택모형(mode choice model)의 모형변수로 포함되는 것이 최근 선진국의 물류계획 실무분야에서 일반적인 추세이다. 하지만 지역유형은 그 동안 개념적으로 명확히 정의되지 못하였으며, 분석모형의 맥락에서 지역유형의 계량적 추정을 다룬 선행연구는 거의 없었다고 할 수 있다. 이런 이유 때문에 중/장기 물류수요예측 및 물류계획에 있어서 인구와 고용의 변화가 지역유형을 어떻게 변화시킬지에 관한 장기적인 예측을 하는 것이 어려웠다. 따라서 본 연구는 물류시설 SOC사업의 성공적 추진을 위하여 물류수요예측의 신뢰수준을 제고하는 데 있어 꼭 필요하고 시급한 연구로서 지역유형(area type)을 고려한 물류수요의 잠재력(potential)분석 방법을 제시하였다.

Steel-Plate 매입형 합성 연결보의 접합부 상세에 따른 내진거동 (Seismic Behavior by Beams-Wall Connections depending upon Joint Details of Embedded Steel-Plate Composite Coupling Beams)

  • 주재형;채승윤;김선규;김우재;전호민;박효선
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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    • pp.130-133
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    • 2006
  • Owing to Higher story tendency and ceiling hight restriction of recent times, even though the depth of Coupling Beam decreases the demand efficiency is coming to be high rather so it is the difficult to satisfy a demand efficiency with the actual existing RC/Steel condition. It has been researched a lot of methods as an alternative plan about these but designer cannot apply them for the reason ; the structure standard and theory background are not taking a triangular position. As accomplishing the test research about the beams-wall connections department of steel-plate composite coupling beams from the research in the study it examines closely the beams-wall connections conduct quality and tries to provide the fundamental data for reasonable and optimum connection department designs. It knows that connection fixation degree and composite conduct degree of member part together become the important variable showing an energy dissipation ability in Test result.

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A Variability Analysis on the Flatfish Production and Revenue using Expectation Hypotheses and GARCH Model

  • Yoon, Hyung-Mo;Yoon, Ji-Young
    • 수산경영론집
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    • 제48권2호
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    • pp.1-17
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    • 2017
  • This work studies the variability of flatfish sales revenue. The theoretical analysis draws functions for equilibrium price and quantity using expectation hypotheses. The functions include unpredictable phenomenon with dummy variable and GARCH. The equilibrium function, using adaptive expectation hypothesis, contains the independent variables of supply and demand, while the equilibrium function, embodying rational expectation hypothesis, includes only the independent variables of supply side, because the demand side disappears by the information extraction process theoretically, if economic subjects build the expectation rational. The empirical analysis shows: the variability of flatfish production has a spillover effect on the variability of revenue with the adaptive expectation hypothesis. In the case when the model has a rational expectation hypothesis, the variability of flatfish production has a spillover effect on the revenue (the mean equation of GARCH model). This study indicates that there is the variability in flatfish production and sales revenue, and the spillover effect between them. The result can help to build of the rational system for the fishery income stability.

공학 융합역량에 대한 산업체와 대학생의 인식 비교분석 (A Study on the Perception about Engineering Convergence Competency between Industry and Engineering Students)

  • 허지숙;황윤자
    • 공학교육연구
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    • 제23권4호
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    • pp.3-13
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    • 2020
  • The purpose of this study is to analyze the differences in the perception and education requirements between industry and engineering students on engineering convergence competency, and to suggest implications for fostering engineers suitable to industry demand and direction of focus improvement in the current engineering education field. To this end, 73 industrial representatives and 104 engineering students are surveyed the engineering convergence competency and educational needs. The results of this analysis are as follows: first, the difference in engineering convergence competency by background variable was significantly different in gender of engineering students. Second, it is found that there is a significant difference between the current level and the required level of engineering convergence competency from an industry perspective. In the IPA results, it shows that new knowledge generation and future-oriented vision skills are urgently needed to be improved. And it is showed that the creative thinking, knowledge utilization, communication, and cooperation capabilities skills need to be maintained continuously. Third, as a result of the analysis of the differences in recognition of the current competency levels between industry and engineering students, there is statistically significant differences in systemic thinking, communication and cooperation, understanding of other academic fields, humanities, and future-oriented perspectives. Therefore, it is necessary to specific plans and efforts to reduce this perception gap should be prepared at the university.

Capital Structure and Financial Performance: A Case of Saudi Petrochemical Industry

  • ALI, Anis;FAISAL, Shaha
    • The Journal of Asian Finance, Economics and Business
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    • 제7권7호
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    • pp.105-112
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    • 2020
  • The study investigates and measures the impact of capital structure, profitability and financial performance on the success of the business organization. Capital structure of the business organization refers to the proportion of external funds and internal funds, i.e., debt and equity. In Saudi Arabia, petrochemicals companies are working on equity, but financial performance reflects negative trend for the period 2004 to 2016. The research is based upon secondary data available on the websites of petrochemicals companies of Saudi Arabia. Financial Ratio variability analysis and Trend Indices of financial ratios (TICBI) measure and compare the financial variability and sensitivity of financial ratios of the business organization. Correlation between Trend Indices (TICBI) of independent variable and dependent variables are to be calculated to know the impact of changes in debt equity on other dependent variables. The results reveal the unexpected performance of petrochemicals companies due to under-utilization of the resources caused by low demand and lower prices of the products governed by some internal and external factors. The study finds that size, demand, cost of production, profitable streams of products, and low cost capital in external funds are the factors responsible for overall growth development of the petrochemicals industry of Saudi Arabia.

한국 최대 전력량 예측을 위한 통계모형 (Statistical Modeling for Forecasting Maximum Electricity Demand in Korea)

  • 윤상후;이영생;박정수
    • Communications for Statistical Applications and Methods
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    • 제16권1호
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    • pp.127-135
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    • 2009
  • 한국의 경제규모가 꾸준히 커감에 따라 가정, 건물, 공장 등에서 필요로 하는 전력량이 지속적으로 증가하고 있다. 전력공급의 안정화를 위해서는 최대전력량보다 전력공급능력이 높아야 한다. 월별 최대전력량을 잘 설명할 수 있는 통계모형을 찾기 위해 Winters 모형, 분해 시계열모형, ARMA 모형, 설명 변수를 통해 추세성분과 계절성분을 교정한 모형을 살펴보았다. 모형의 예측력 비교 기준으로 모형적합으로부터 구한 RMSE와 MAPE가 사용되었다. 여름철 최대전력량을 예측하기 위해 평균기온과 열대야 일수를 설명 변수로 갖는 시계열 모형이 가장 우수하였다. 아울러 외부요인을 갖는 극단분포 모형을 이용한 분석을 시도하였다.

대학생의 생활매너 수행과 교육요구 및 관련변인 분석 (University Students' Everyday Manners and Demands for Manners Education and the Influence Variables)

  • 엄문자;류미현
    • 가정과삶의질연구
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    • 제22권6호
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    • pp.233-242
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    • 2004
  • The main objective of this study is to provide baseline data and materials to be used for developing an manners education program. Such an educational program will help enhance the manners of university students. A stratified random sampling method was applied to collect data. Originally, 800 questionnaires were distributed to university students during the period between May 10 and May 31, 2m, and of the completed questionnaires, 7n3 were used for data analysis. 'The following findings were obtained:1. University students 'level of everyday manners was shown to be moderate, and the mean score was 6.76 (67.61/100 Points). 2. The level of demands for everyday manners education was shown to be high and the mean score was 8.05 (67.61/100 Points). 3. The variable that had the greatest impact on the level of everyday manners was the subjective knowledge about everyday manners, whereas gender affected the demand for education the most strongly.

FOSM 방법을 이용한 내진성능 중요부재 판별법 (Identifying Significant Components of Structures for Seismic Performance Using FOSM Method)

  • 이태형;칼리드 모살람
    • 한국지진공학회논문집
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    • 제13권4호
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    • pp.37-45
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    • 2009
  • 구조 시스템을 구성하는 구조부재들의 상대적인 중요도를 판별하는 것은 성능기반 지진공학에서 매우 중요한 과정이다. 확률기법의 하나인 First-Order Second Moment 방법을 이용하여, 각 구조부재들의 불확실한 성능 때문에 발생하는 구조 시스템의 요구 성능의 불확실성을 예측할 수 있고, 이런 과정을 통해서 구조부재의 중요도를 판별할 수 있다. 특정한 구조부재의 불확실한 성능에 대한 구조 시스템의 요구성능이 민감할수록 그 구조부재의 중요도는 높아진다는 점을 이용하여 중요부재를 판별한다. 따라서 요구성능의 민감도가 상대적으로 큰 구조부재는 그렇지 않은 부재보다 더 중요하다고 할 수 있다. 개발된 중요부재 판별법은 연성 철근콘크리트 프레임의 중요부재를 판별하는 과정에 적용함으로써 방법을 검증하였고, 적용 가능성을 보여주었다.