• Title/Summary/Keyword: Performance criterion

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Using the corrected Akaike's information criterion for model selection (모형 선택에서의 수정된 AIC 사용에 대하여)

  • Song, Eunjung;Won, Sungho;Lee, Woojoo
    • The Korean Journal of Applied Statistics
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    • v.30 no.1
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    • pp.119-133
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    • 2017
  • Corrected Akaike's information criterion (AICc) is known to have better finite sample properties. However, Akaike's information criterion (AIC) is still widely used to select an optimal prediction model among several candidate models due to of a lack of research on benefits obtained using AICc. In this paper, we compare the performance of AIC and AICc through numerical simulations and confirm the advantage of using AICc. In addition, we also consider the performance of quasi Akaike's information criterion (QAIC) and the corrected quasi Akaike's information criterion (QAICc) for binomial and Poisson data under overdispersion phenomenon.

Developing of a Criterion for Selecting and Producing of Performance (과학 수행 평가 문항의 선정 및 제작을 위한 평가 준거의 개발)

  • Kim, Eun-Jin;Park, Hyun-Ju;Kang, Ho-Kam;Noh, Suk-Gu
    • Journal of The Korean Association For Science Education
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    • v.23 no.1
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    • pp.75-85
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    • 2003
  • We have developed of a criterion that would help to select and develop performance assessments in science education. There are six categories of a criterion: Fidelity, satisfaction, content validity, fairness & suitability, reliability & objectivity, and usability. There are the total of 25 sub-categories under the six categories. Five science educators evaluated the validity of the criterion. For reliability of the criterion, Kendall's tau-b was used. Eight science educators and elementary teachers evaluated three performance assessment tasks for the correspondence of the criterion. This study also discuss the implications of this criterion as well.

Evaluation of Vibration Reduction Performance of Operator Seat for Agricultural Tractors (트랙터 운전석의 진동 감쇠 성능 평가)

  • Shin, Chang-Seop;Kim, Kyeong-Uk
    • Journal of Biosystems Engineering
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    • v.36 no.1
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    • pp.1-8
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    • 2011
  • Six models of operator seat supplied to local tractor manufacturers were tested in the laboratory in accordance with ISO 5007 and 78/764/EEC. No models out of the six met the allowable damping and transmissibility performance criteria of both ISO 5007 and 78/764/EEC. From the ISO criterion standpoint, one model failed in damping performance and 4 models in isolation performance. From the 78/764/EEC criterion standpoint, 4 models failed in damping performance and 4 models in isolation performance. However none of them failed in all of the criteria, either. Each model met the one acceptance criterion but failed in another. This indicated that operator seat must be improved to meet the current ISO 5007 or 78/764/EEC and the exposure limit value that will be enforced in EU tractor market from 2014 by EU Directive 2002/44 EC.

The effect of the new stopping criterion on the genetic algorithm performance

  • Kaya, Mustafa;Genc, Asim
    • Computers and Concrete
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    • v.27 no.1
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    • pp.63-71
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    • 2021
  • In this study, a new stopping criterion, called "backward controlled stopping criterion" (BCSC), was proposed to be used in Genetic Algorithms. In the study, the available stopping citeria; adaptive stopping citerion, evolution time, fitness threshold, fitness convergence, population convergence, gene convergence, and developed stopping criterion were applied to the following four comparison problems; high strength concrete mix design, pre-stressed precast concrete beam, travelling salesman and reinforced concrete deep beam problems. When completed the analysis, the developed stopping criterion was found to be more accomplished than available criteria, and was able to research a much larger area in the space design supplying higher fitness values.

A Simple Efficient Stopping Criterion for Turbo Decoder

  • Kim, Young-Sup;Ra, Sung-Woong
    • ETRI Journal
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    • v.28 no.6
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    • pp.790-792
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    • 2006
  • The performance of a turbo decoder depends strongly on the number of iterations in its decoding process. It is necessary to stop the decoding process at an appropriate moment to alleviate the serious burden, in terms of both the computational speed and latency, part of which is associated with too many iterations. In this letter, we introduce a criterion for finding the opportune moment to stop the decoding process, called a hard decision aided criterion based on bit interleaved parity, which is known to have much simpler hardware logic, compared with other schemes, and does not lead to any significant performance degradation.

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Performance testing of a FastScan whole body counter using an artificial neural network

  • Cho, Moonhyung;Weon, Yuho;Jung, Taekmin
    • Nuclear Engineering and Technology
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    • v.54 no.8
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    • pp.3043-3050
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    • 2022
  • In Korea, all nuclear power plants (NPPs) participate in annual performance tests including in vivo measurements using the FastScan, a stand type whole body counter (WBC), manufactured by Canberra. In 2018, all Korean NPPs satisfied the testing criterion, the root mean square error (RMSE) ≤ 0.25, for the whole body configuration, but three NPPs which participated in an additional lung configuration test in the fission and activation product category did not meet the criterion. Due to the low resolution of the FastScan NaI(Tl) detectors, the conventional peak analysis (PA) method of the FastScan did not show sufficient performance to meet the criterion in the presence of interfering radioisotopes (RIs), 134Cs and 137Cs. In this study, we developed an artificial neural network (ANN) to improve the performance of the FastScan in the lung configuration. All of the RMSE values derived by the ANN satisfied the criterion, even though the photopeaks of 134Cs and 137Cs interfered with those of the analytes or the analyte photopeaks were located in a low-energy region below 300 keV. Since the ANN performed better than the PA method, it would be expected to be a promising approach to improve the accuracy and precision of in vivo FastScan measurement for the lung configuration.

Development of an Algorithm for Searching Optimal Temperature Setpoint for Lettuce in Greenhouse Using Crop Growth Model (작물생장모델을 이용한 상추의 온실 최적설정온도 탐색 알고리즘의 개발)

  • 류관희;김기영;김희구;채희연
    • Journal of Biosystems Engineering
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    • v.24 no.5
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    • pp.445-452
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    • 1999
  • This study was conducted to develop a searching algorithm for optimal daily temperature setpoint greenhouse. An algorithm using crop growth and energy models was developed to determine optimum crop growth environment. The results of this study were as follows: 1. Mathematical models for crop growth and energy consumption were derived to define optimal daily temperature setpoint. 2. Optimum temperature setpoint, which could maximize performance criterion, was determined by using Pontryagin maximum principle. 3. Dynamic control of daily temperature using the developed algorithm showed higher performance criterion than static control with fixed temperature setpoint. Performance criteria for dynamic control models were with simulated periodic weather data and with real weather data, increased by 48% and 60%, respectively.

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Performance Criterion-based Polynomial Calibration Model for Laser Scan Camera (레이저 스캔 카메라 보정을 위한 성능지수기반 다항식 모델)

  • Baek, Gyeong-Dong;Cheon, Seong-Pyo;Kim, Su-Dae;Kim, Sung-Shin
    • Journal of the Korean Institute of Intelligent Systems
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    • v.21 no.5
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    • pp.555-563
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    • 2011
  • The goal of image calibration is to find a relation between image and world coordinates. Conventional image calibration uses physical camera model that is able to reflect camera's optical properties between image and world coordinates. In this paper, we try to calibrate images distortion using performance criterion-based polynomial model which assumes that the relation between image and world coordinates can be identified by polynomial equation and its order and parameters are able to be estimated with image and object coordinate values and performance criterion. In order to overcome existing limitations of the conventional image calibration model, namely, over-fitting feature, the performance criterion-based polynomial model is proposed. The efficiency of proposed method can be verified with 2D images that were taken by laser scan camera.

A Study on Hardened Properties and Durability of Concrete according to Unit-Water Content (배합수량 변동에 따른 콘크리트의 경화성상 및 내구성에 관한 연구)

  • Koo, Kyung-Mo;Lim, Chang-Hyuck;Lee, Eui-Bae;Kim, Young-Sun;Kim, Young-Duck;Kim, Gyu-Yong
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2009.05b
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    • pp.45-48
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    • 2009
  • The performance of concrete mainly depend upon its water-cement ratio. If water percentage is excess in concrete, it may cause the degradation of performance. Because of these reasons, the change of water content is managed by using various evaluation method of unit water content. And criterion for the change of water content is regulated and used. However the criterion is set only considering production error and measurement error but criterion does not consider performance degradation of concrete. Therefore this study tries to investigate degradation of performance while adding extra water by artificial manipulation or management error in concrete, The contents of extra water for tests are set as 0, 20, 40, 60kg/m3, to examine the performance degradation of concrete, strength, shrinkage, cracks, carbonation are tested This study conclude that, when extra water content is excess than 20kg/m3 in concrete, then performance level of concrete declined rapidly. 80 it is very important to maintain quality of concrete for its better performance.

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Reliability Assessment Criteria of Sensor Module for Lighting Fixtures (조명용센서모듈의 신뢰성평가기준)

  • Jeong, Hee-Suk;Park, Chang-Kyu;Jeong, Hai-Sung;Baik, Jai-Wook
    • Journal of Applied Reliability
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    • v.10 no.1
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    • pp.11-24
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    • 2010
  • Lighting industry is rapidly being developed as the ubiquitous society based on sensor network emerges. This kind of paradigm shift brings the society convergence of technologies which leads to smart lighting system as well as the integration of interior and sensibility control. However, standards for sensors have not been firmly established, and problems related to quality and malfunction have been brought up, thereby calling for careful approach to the enhancement and assessment of reliability of the item. In this article reliability assessment criteria for sensor module for lighting fixtures is established in terms of performance assessment criterion and reliability assessment criterion.