• 제목/요약/키워드: Data Model Evaluation

검색결과 4,034건 처리시간 0.033초

A semiparametric method to measure predictive accuracy of covariates for doubly censored survival outcomes

  • Han, Seungbong;Lee, JungBok
    • Communications for Statistical Applications and Methods
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    • 제23권4호
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    • pp.343-353
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    • 2016
  • In doubly-censored data, an originating event time and a terminating event time are interval-censored. In certain analyses of such data, a researcher might be interested in the elapsed time between the originating and terminating events as well as regression modeling with risk factors. Therefore, in this study, we introduce a model evaluation method to measure the predictive ability of a model based on negative predictive values. We use a semiparametric estimate of the predictive accuracy to provide a simple and flexible method for model evaluation of doubly-censored survival outcomes. Additionally, we used simulation studies and tested data from a prostate cancer trial to illustrate the practical advantages of our approach. We believe that this method could be widely used to build prediction models or nomograms.

An Application of a Sunshine Duration Model Based on GIS Data to Suitability of Measurement Site around the Seonleung Park

  • Kim, Eun-Ryoung;Kim, Jae-Jin
    • 대한원격탐사학회지
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    • 제31권4호
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    • pp.331-336
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    • 2015
  • In this study, a numerical model developed for sunshine duration based on GIS data was used. This model considers blocking caused by topography and buildings and it is properly applicable to evaluation of sunshine duration environment in urban areas. The model reasonably well predicted the solar altitude and azimuth angels, compared to those provided by Korea Astronomy and Space Science Institute (KASI). The developed model was applied to evaluation of sunshine duration environment around the Seonleung Park located near a building-congested area in Seoul. The model well reproduced shadow caused by buildings and/or topography in the numerical domain at 09:00 on August 1, 2015. In addition, the model was applied to finding a suitable measurement sites for pyrheliometer around the Seonleung Park. The model was also usefully applied to finding a suitable site for pyrheliometer in an urban area.

Neutron Cross Section Evaluation on Mo-95, Tc-99, Ru-101 and Rh-1()3 in the Fast Energy Region

  • Lee, Y. D.;J. H. Chang
    • Nuclear Engineering and Technology
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    • 제34권6호
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    • pp.533-544
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    • 2002
  • The neutron induced nuclear data for Mo-95, Tc-99, Ru-101 and Rh-103 was calculated and evaluated in the fast energy region. The energy dependent optical model potential parameters were extracted based on the recent experimental data and applied up to 20 MeV. The s-wave strength function was calculated from the parameters. Spherical optical model, statistical model in equilibrium energy, multistep direct and multistep compound model in pre-equilibrium energy and direct capture model were used in the calculation. The theoretically calculated cross sections were compared with the experimental data and the evaluated files The model- calculated total and capture cross sections were in good agreement with the reference experimental data. The direct capture contribution improved the capture cross sections in pre- equilibrium region. The evaluated cross section results were compiled to ENDF-6 format and will improve the ENDF/B-Vl.

Neutron Cross Section Evaluation on Dy Isotopes

  • Lee, Y. D.;J. H. Chang
    • Nuclear Engineering and Technology
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    • 제34권2호
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    • pp.154-164
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    • 2002
  • Neutron cross section data on Dy-160, Dy-161, Dy-162, Dy-163 and Dy-164 were calculated and evaluated in the energy range of 1 keV to 20 MeV using a spherical optical model, statistical model and pre-equilibrium model. The energy dependent optical model potential parameters were obtained based on the recent experimental data. The width fluctuation correction in Hauser-Feshbach particle decay and the quantum mechanical approach in pre-equilibrium analysis were introduced and gave a better cross section calculation in EMPIRE-II. The total, elastic scattering and threshold reaction cross sections were evaluated and compared with the evaluated files. The model calculated (n, tot), (n, ${\gamma}$) and (n, p) cross sections were in good agreement with the experimental data in the measured energy range. The results will be applied to ENDF/B-VI for data improvement.

Neutron Cross Section Evaluation on Pr-141, Nd-143, Nd-145, Sm-147 and Sm-149

  • Lee, Y. D.;J. H. Chang
    • Nuclear Engineering and Technology
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    • 제34권4호
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    • pp.370-381
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    • 2002
  • The neutron induced nuclear data for Pr-141, Nd-143, Nd-145, Sm-147 and Sm-149 were calculated and evaluated from 10 keV to 20 MeV. The energy dependent optical model potential parameters were extracted based on the recent experimental data and applied up to 20 MeV. The s-wave strength function was calculated. Spherical optical model , statistical model in equilibrium energy, multistep direct and multistep compound model in pre-equilibrium energy and direct capture model were introduced in Empire calculation. The theoretically calculated cross sections were compared with the experimental data and the evaluated files. The model calculated total and capture cross sections were in good agreement with the reference experimental data. The capture cross sections in pre-equilibrium were enhanced in recent released Empire version. The evaluated cross section results were compiled to ENDF-6 format and will improve the ENDF/B-Vl.

헤도닉 모델을 활용한 공동주택 리모델링 사업성 평가방법 (A Feasibility Study Method for Apartment Remodeling by Hedonic Model)

  • 유인근;김천학;윤여완;양극영
    • 한국건축시공학회지
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    • 제4권3호
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    • pp.117-124
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    • 2004
  • This study aims to evaluate the feasibility of remodeling business by predicting the future price of apartment house after remodeling using Hedonic Price Model. The data concerning such 8 independent variables as location, unit size, unit plan, landscape, parking, the number of elapsed years after completion, number of units, brand per apartment unit from 25 regions in Seoul metropolitan city were collected and evaluated by established evaluation criteria. The coefficients affecting the price of apartment unit were made by way of linear multi-regression and put into Hedonic Price Model. The feasibility evaluation model for apartment was made and verified by data of remodelled apartment. The predicted results using suggested evaluation model coincide with actual apartment market situations.

IT 사업의 경제성 평가 모형 설계 (Economics Evaluation Model for Information Systems Project)

  • 이상원;김성현;박승범;안현섭
    • 한국컴퓨터정보학회:학술대회논문집
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    • 한국컴퓨터정보학회 2014년도 제50차 하계학술대회논문집 22권2호
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    • pp.97-98
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    • 2014
  • Lots of investment projects of new development and redevelopment for information systems have been not taken care of in the field of administration and evaluation, for these information systems projects have unique characteristics such as technology sensitiveness, network effectiveness, embeddedness, and externality. In fact, quantitative and qualitative evaluation of investments in information systems projects are not sufficient. It is critically important to generally evaluate benefits of development or operation cost, urgency, external effects, and so on. In addition, the efficient monitoring and effective analysis of information systems are surely needed for beneficient results of investment in information systems. We propose an economics evaluation model for information systems projects.

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웹 2.0을 고려한 유저 참여 관점에서의 인터넷 GIS 사이트 평가기준 설정을 위한 연구 (Investigation for Evaluation factor of Internet GIS Sites in the Context of User considering Web 2.0)

  • 이호진;박희준
    • 한국데이타베이스학회:학술대회논문집
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    • 한국데이타베이스학회 2008년도 연합학회학술대회
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    • pp.379-388
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    • 2008
  • 초기 사업자들에 의해 일방적으로 정보가 제공되던 인터넷 GIS 사이트는 Web 2.0의 패러다임과 함께 사용자들에 의해서 정보가 생산되고, 평가되는 형태로 변화하였다. 기존의 일반적인 웹사이트의 평가모델과 GIS 사이트 평가 모델에 대해서 살펴보고, Web 2.0을 고려하여 보완된 GIS 사이트 평가모델의 기준점을 을 제시하고자 한다. 본 연구를 통해 제안된 평가 모델의 기준점은 사용자 참여 정도를 고려한 평가 기준점으로써 이를 발전시켜 GIS 2.0 에 대한 평가모델을 제안할 수 있을 것이다.

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모델의 타당성 평가에 기초한 로바스트 동정에 관한 연구 (A Study on Robust Identification Based on the Validation Evaluation of Model)

  • 이동철
    • 동력기계공학회지
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    • 제4권3호
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    • pp.72-80
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    • 2000
  • In order to design a stable robust controller, nominal model, and the upper bound about the uncertainty which is the error of the model are needed. The problem to estimate the nominal model of controlled system and the upper bound of uncertainty at the same time is called robust identification. When the nominal model of controlled system and the upper bound of uncertainty in relation to robust identification are given, the evaluation of the validity of the model and the upper bound makes it possible to distinguish whether there is a model which explains observation data including disturbance among the model set. This paper suggests a method to identity the uncertainty which removes disturbance and expounds observation data by giving a probable postulation and plural data set to disturbance. It also examines the suggested method through a numerical computation simulation and validates its effectiveness.

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모델의 타당성 평가에 기초한 로바스트 동정에 관한 연구 (A Study on Robust Identification Based on the Validation Evaluation of Model)

  • 이동철;정형환;배종일
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 하계학술대회 논문집 D
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    • pp.2690-2692
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    • 2000
  • In order to design a stable robust controller, nominal model, and the upper bound about the uncertainty which is the error of the model are needed. The problem to estimate the nominal model of controlled system and the upper bound of uncertainty at the same time is called robust identifcation. When the nominal model of controlled system and the upper bound of uncertainty in relation to robust identifcation are given, the evaluation of the validity of the model and the upper bound makes it possible to distinguish whether there is a model which explains observation data including disturbance among the model set. This paper suggests a method to identify the uncertainty which removes disturbance and expounds observation data by giving a probable postulation and plural data set to disturbance. It also examines the suggested method through a numerical computation simulation and validates its effectiveness.

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