• Title/Summary/Keyword: Demand estimation

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Railroad Travel Demand Estimation System Suggestion (철도수송수요 예측시스템 제안)

  • Min, Jae-Hong
    • Proceedings of the KSR Conference
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    • 2003.10b
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    • pp.3-7
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    • 2003
  • It is very difficult to find optimal train operation plan when analyzing the economic investment using traditional railroad travel demand estimation method. Train operation plan depends on travel demand and vice versa. To solve this problem, this study suggests a demand estimation method to address an optimal train operation scheme with the modal spilt using initial train operation plan and trip assignment.

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Development of the Estimation System for Agricultural Water Demand (농업용수 수요량 산정 시스템 개발(관개배수 \circled1))

  • 이광야;김선주;김현영;서영제
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 2000.10a
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    • pp.114-119
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    • 2000
  • To estimate Agricultural water demand, many factors such as weather, type of crop, soil, cultivation method, crop coefficient and cultivation area, etc. must be considered. But it is not easy to estimate water demand in consideration of these many factors, which are variable according to a period and regional environment. So, this study provides estimation system for agricultural water demand(ESAD) in order to estimate water demand easily and accurately, calculates the present and future agricultural water demand and arranges all factors needed for water demand estimation. This study calibrates the application of estimation system for agricultural water demand with the data observed in the other Studies and analyzes agricultural water demand nationwide.

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Development of the Estimation System for Agricultural Water Demand (농업용수 수요량 산정 시스템 개발)

  • 이광야;김선주
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.43 no.1
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    • pp.53-65
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    • 2001
  • To estimate agricultural water demand, many factors such as weather, crops, soil, cultivation method, crop coefficient and cultivation area, etc. must be considered. But it is not easy to estimate water demand in consideration of these factors, which are variable according to growth stage and regional environment. This study provides estimation system for agricultural water demand(ESAD) in order to estimate water demand easily and accurately, and arranges all factors needed for water demand estimation. This study identifies the application of estimation system for agricultural water demand with the data observed in the other studies, and analyzes nationwide agricultural water demand. The results are as follows. 1) The practice of different rice cultivation in the paddy field resulted in different water demands. Water depth and infiltration ratio in paddy are the most important factors to estimate water demand. The water depths in paddy simulated by ESAD is very similar to the observed ones. 2) Water demand of upland crops varies with the crops, soil, etc.. Effective rainfall estimated by daily routing of soil moisture varies according to the crops, soil, and effective soil zone(root depth). As crop root become grown, effective rainfall and an amount of irrigation water has been increased. 3) The current unit water demand of upland crops applied as 500mm or 550mm to estimate water demand does not reflect the differences caused by the crops, regional surrounding, weather condition, etc. Results from ESAD for the estimation of water demand of upland crops show that ESAD can simulate the actual field conditions reasonably because it simulates the actual irrigation practices with the daily routing of soil moisture.

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Criterion Thesis for Estimation of Power Demand in New Housing Development (신규 주택단지 전력수요 산정 기준 정립)

  • Choi, Sang-Bong;Nam, Ki-Young;Kim, Dae-Kyeong;Jeong, Seong-Hwan;Ryoo, Hee-Seok
    • Proceedings of the KIEE Conference
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    • 2002.11b
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    • pp.145-147
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    • 2002
  • Recently, according to business conditions ;in domestic are beginning to liven up, there is a lively discussion about new housing construction around the center of the Metropolitan area. It is considerable difficult for estimation of power demand exactly to expand power facilities in these area. However. criterion thesis for estimation of power demand which has been applied in present condition is already passed through the 10 years, the reliability to calculate power demand in these area go down far away. Accordingly, it is raised for methodology to evaluate new type of power demand in new housing development in domestic. This paper presents new criterion thesis for estimation of power demand in new housing development through survey and analysis in example area.

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An Study on Basis for Demand Estimation of Lifetime Sports Facilities (생활체육시설의 수요예측을 위한 기초적 연구)

  • Min, Young-Gi
    • Journal of The Korean Digital Architecture Interior Association
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    • v.3 no.1
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    • pp.15-22
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    • 2003
  • The purpose of this study was to analyze basic conditions for the demand estimation erection of lifetime sports facilities. This is described the whole concept of lifetime sports(sport for all) for helping the understanding of its concept correctly. Firstly, second chapter was examined the significance, function and role of lifetime sports in modern society. Secondly, third and forth chapter was examined demand and participation of lifetime sports activities for demand estimation of lifetime sports facilities. Participation rate is on the rise by the increase in income and leisure time to some extent, but after that it stops rising. In other words, the same participation rate persists without additional increase in participation by the changes in time deepening and in the patterns of demand for lifetime sports activities.

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Investigation of shear effects on the capacity and demand estimation of RC buildings

  • Palanci, Mehmet;Kalkan, Ali;Sene, Sevket Murat
    • Structural Engineering and Mechanics
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    • v.60 no.6
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    • pp.1021-1038
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    • 2016
  • Considerable part of reinforced concrete building has suffered from destructive earthquakes in Turkey. This situation makes necessary to determine nonlinear behavior and seismic performance of existing RC buildings. Inelastic response of buildings to static and dynamic actions should be determined by considering both flexural plastic hinges and brittle shear hinges. However, shear capacities of members are generally neglected due to time saving issues and convergence problems and only flexural response of buildings are considered in performance assessment studies. On the other hand, recent earthquakes showed that the performance of older buildings is mostly controlled by shear capacities of members rather than flexure. Demand estimation is as important as capacity estimation for the reliable performance prediction in existing RC buildings. Demand estimation methods based on strength reduction factor (R), ductility (${\mu}$), and period (T) parameters ($R-{\mu}-T$) and damping dependent demand formulations are widely discussed and studied by various researchers. Adopted form of $R-{\mu}-T$ based demand estimation method presented in Eurocode 8 and Turkish Earthquake Code-2007 and damping based Capacity Spectrum Method presented in ATC-40 document are the typical examples of these two different approaches. In this study, eight different existing RC buildings, constructed before and after Turkish Earthquake Code-1998, are selected. Capacity curves of selected buildings are obtained with and without considering the brittle shear capacities of members. Seismic drift demands occurred in buildings are determined by using both $R-{\mu}-T$ and damping based estimation methods. Results have shown that not only capacity estimation methods but also demand estimation approaches affect the performance of buildings notably. It is concluded that including or excluding the shear capacity of members in nonlinear modeling of existing buildings significantly affects the strength and deformation capacities and hence the performance of buildings.

Modeling Procedure to Adapt to Change of Trend of Water Demand: Application of Bayesian Parameter Estimation (물수요의 추세 변화의 적응을 위한 모델링 절차 제시:베이지안 매개변수 산정법 적용)

  • Lee, Sangeun;Park, Heekyung
    • Journal of Korean Society of Water and Wastewater
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    • v.23 no.2
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    • pp.241-249
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    • 2009
  • It is well known that the trend of water demand in large-size water supply systems has been suddenly changed, and many expansions of water supply facilities become unnecessary. To be cost-effective, thus, politicians as well as many professionals lay stress on the adaptive management of water supply facilities. Failure in adapting to the new trend of demand is sure to be the most critical reason of unnecessary expansions. Hence, we try to develop the model and modeling procedure that do not depend on the old data of demand, and provide engineers with the fast learning process. To forecast water demand of Seoul, the Bayesian parameter estimation was applied, which is a representative method for statistical pattern recognition. It results that we can get a useful time-series model after observing water demand during 6 years, although trend of water demand were suddenly changed.

A study on the prediction of the generation of domestic sewage by improvement of water demand estimation (생활용수 수요추정방법 개선에 의한 하수발생량 예측에 관한 연구)

  • 김재윤
    • Journal of Environmental Science International
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    • v.11 no.12
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    • pp.1275-1279
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    • 2002
  • This study was performed to improve water demand estimation and analize correlation between generation of domestic sewage and domestic water use. To improve the prediction of water demand estimation, new water demand equation was developed. The results is as follows. $InQ_t = {\beta}_0+{\beta}_1InP_t+{\beta}_2InY_t+{\beta}_3InH_t+{varepsilon}_t$By using the statistical analysis of the "generation of domestic sewage" and "domestic water use", the regression equation between them is formed. The result is as follows. Generation of domestic sewage : 0.8487 $\times$ Domestic water use + 684.57 ($R^2$= 0.972)>$R^2$= 0.972)

Bayesian approach for the accuracy evaluating of the seismic demand estimation of SMRF

  • Ayoub Mehri Dehno;Hasan Aghabarati;Mehdi Mahdavi Adeli
    • Earthquakes and Structures
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    • v.26 no.2
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    • pp.117-130
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    • 2024
  • Probabilistic model of seismic demand is the main tool used for seismic demand estimation, which is a fundamental component of the new performance-based design method. This model seeks to mathematically relate the seismic demand parameter and the ground motion intensity measure. This study is intended to use Bayesian analysis to evaluate the accuracy of the seismic demand estimation of Steel moment resisting frames (SMRFs) through a completely Bayesian method in statistical calculations. In this study, two types of intensity measures (earthquake intensity-related indices such as magnitude and distance and intensity indices related to ground motion and spectral response including peak ground acceleration (PGA) and spectral acceleration (SA)) have been used to form the models. In addition, an extensive database consisting of sixty accelerograms was used for time-series analysis, and the target structures included five SMRFs of three, six, nine, twelve and fifteen stories. The results of this study showed that for low-rise frames, first mode spectral acceleration index is sufficient to accurately estimate demand. However, for high-rise frames, two parameters should be used to increase the accuracy. In addition, adding the product of the square of earthquake magnitude multiplied by distance to the model can significantly increase the accuracy of seismic demand estimation.

An Exploratory Study on the New Product Demand Curve Estimation Using Online Auction Data

  • Shim Seon-Young;Lee Byung-Tae
    • Management Science and Financial Engineering
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    • v.11 no.3
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    • pp.125-136
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    • 2005
  • As the importance of time-based competition is increasing, information systems for supporting the immediate decision making is strongly required. Especially high -tech product firms are under extreme pressure of rapid response to the demand side due to relatively short life cycle of the product. Therefore, the objective of our research is proposing a framework of estimating demand curve based on e-auction data, which is extremely easy to access and well reflect the limited demand curve in that channel. Firstly, we identify the advantages of using e-auction data for full demand curve estimation and then verify it using Agent-Eased-Modeling and Tobin's censored regression model.