• 제목/요약/키워드: Estimating the validity

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A Note on Bootstrapping M-estimators in TAR Models

  • Kim, Sahmyeong
    • Communications for Statistical Applications and Methods
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    • 제7권3호
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    • pp.837-843
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    • 2000
  • Kreiss and Franke(192) and Allen and Datta(1999) proposed bootstrapping the M-estimators in ARMA models. In this paper, we introduce the robust estimating function and investigate the bootstrap approximations of the M-estimators which are solutions of the estimating equations in TAR models. A number of simulation results are presented to estimate the sampling distribution of the M-estimators, and asymptotic validity of the bootstrap for the M-estimators is established.

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VALIDITY REGIONS OF THEORETICAL MODELS FOR ESTIMATING THE RCS OF LOSSY DIELECTRIC CYLINDERS

  • Hong, Jin-Young;Kwon, Soon-Gu;Oh, Yi-Sok
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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    • pp.369-373
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    • 2007
  • This paper presents an examination of theoretical scattering models for radar cross sections (RCS) of lossy dielectric cylinders, such as exact analytical solution, low frequency approximation (Rayleigh) and high frequency approximation (Physical Optics). The validity regions of the PO and Rayleigh models are closely examined with exact solution in terms of various wavelengths and dielectric constants of a circular cylinder. And also this paper examines the PO and Rayleigh models for back and forward scatter RCS of a cylinder at various incidence angles and polarizations. It was found that the PO and Rayleigh model have their validity regions for estimating the RCS of a circular cylinder.

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투자타당성검토와 예비견적 (Research for Investment Validity and Preliminary Estimating)

  • 이근희;박상민
    • 산업경영시스템학회지
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    • 제11권18호
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    • pp.1-5
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    • 1988
  • In this study we have provided one solution to overcome mistakes with limited technical staffs, capitals and times may be the computer for cost estimating. In view of the speed and the ability to draw on funds of information, we shall see that computer estimating models will become the exhibited and the accepted norm of operation by continuous research. Therefore, the computer is broadly serving the needs of many engineering disciplines and in the area of engineering design and industrial application, inexhaustible developed softwares are presented more easy speed and various application for Cost Engineering.

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An Estimation of Nonlinear Time Series with ARCH errors using ECtBnS algorithm

  • Asato, Hajime;Miyagi, Hauao;Yamashita, Katsumi
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 ITC-CSCC -2
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    • pp.1111-1114
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    • 2000
  • In this paper, a method of estimating second-order Volterra model with ARCH errors is presented. Then we use an ECLMS algorithm for noise canceling of nonlinear time series. The validity of the proposed method is demonstrated for estimating second-order Volterra model with ARCH errors, using computer simulations.

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통계기법 점검표 작성시 타당성 평가방법 (The method of evaluating the validity in making the checklist of statistical method)

  • 이상복;김말숙
    • Journal of the Korean Data and Information Science Society
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    • 제9권2호
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    • pp.323-336
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    • 1998
  • 점검표 설계상의 타당성 평가이론에 근거한 점검표 설계 단계별 타당성 평가와 점검표 사용목적에 따른 타당성 평가방법을 제안하여 한국의류학회지를 대상으로 평가이론에 입각하여 점검표의 각 단계별 타당성 평가기준을 설정하였다.

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Influence of an Observation on the t-statistic

  • Kim, Hong-Gie;Kim, Kyung-Hee
    • Communications for Statistical Applications and Methods
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    • 제12권2호
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    • pp.453-462
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    • 2005
  • We derive the influence function on t statistic and find its feature; the influence function on t statistic has two forms depending on the value of ${\mu}_0$. Sample influence functions are used to verify the validity of the derived influence function. We use random samples from normal distribution to show the validity of the function. The simulation study proves that the obtained influence function is very accurate to in estimating changes in t statistic when an observation is added or deleted.

경관영향평가 항목선정을 위한 타당성 평가 (Estimation of Validity for Item Selecting of Landscape Impact Assessment)

  • 오명성;조현주;이현택;나정화
    • Current Research on Agriculture and Life Sciences
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    • 제26권
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    • pp.7-15
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    • 2008
  • This research is significant in terms of estimating the validity by setting evaluation items in view of integrating not only original beauty and visual areas but also natural ecological areas based on questionnaire. The results are as follows. 1) According to literature study, 17 items such as variety, the character of sites in terms of landscape, the beauty of landscape, visibility, and ratio of green visibility are selected. Also, 21 items such as variety of animals and plants species, size of green area, and ecological naturalness are selected in the area of landscape ecological resources. 2) As a result of questionnaire of the group of landscape experts, animals and plants ecological areas show 5.6341, the highest in importance analysis according to assessment areas. Also, as a result of importance analysis on items in each area, for example, in the area of visual resources, the item of skyline analysis is 6.0488, the highest. 3) As a result of corelation of item meaning on landscape effect assesment, for example, meaningness of psychological assessment item and landscape site item indicate 0.710, the highest coefficient correlation. 4) As critical assessment items per unit project, items such as damage minimization of original land features for project in terms of point, ratio of green visibility, variety of animals and plants species marked above 8.0 as high important medium. The project in terms of line, minimization of original land features, preservation of worthy biotope showed high point and the character of sites in terms of landscape, minimization of original land features, the size of green area, and analysis of skyline marked above 8.5 as high importance points. On the contrary, items for climate and soil showed relatively low points.

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Estimating the Validity of CPTED Guidelines on Residence Hall in University: Through the Comparison between CPTED Checklists and Space Syntax Analysis

  • Han, Dongho;Park, Changbae
    • Architectural research
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    • 제17권4호
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    • pp.117-126
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    • 2015
  • University residence halls have become one of the most important issues for students when selecting their academic institutions. However, in South Korea, while universities maintain technologically up-to-date facilities, when it comes to safety or security, the management is unsatisfactory. As a result, the number of violent crime has been increasing. However, there are few researches in terms of practical validity of CPTED Guidelines even though a myriad of researchers study about CPTED Guidelines. Therefore, this study endeavours to investigate the validity of theoretical CPTED Guidelines that to what extent it might be adopted for design process. As a methodology, Space Syntax Convex map and Visibility Graph Analysis (VGA) are chosen. As a result, since the types of space which have a high level of Space Syntax Index are analogous with space treated on CPTED Guidelines, it roughly shows that the theoretical CPTED Guidelines could be adopted in practical architectural design process. Furthermore, it reveals that there is a close relationship between detail design guide stated in CPTED Guidelines and the result of VGA. That is, through the analysis, it is proved that the validity of CPTED Guidelines is quite enough to be adopted in practical design process.

수치 시뮬레이션 방법을 이용한 어업실습선 백경호의 조종성 추정 (Estimation of maneuverability of fisheries training vessel BAEK-KYUNG using numerical simulation method)

  • 김수형;이춘기;이유원
    • 수산해양기술연구
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    • 제57권3호
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    • pp.246-255
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    • 2021
  • Most fishing vessels are less than 100 m in length (LBP), which is not mandatory for the IMO standards for ship maneuverability. Therefore, research on estimating the maneuverability of fishing vessel hull shapes are somewhat lacking compared to that of merchant ship hull shapes, and at the design stage, the numerical simulation method developed for merchant ships are applied without modification to estimate the maneuverability. Since this can cause estimation errors, the authors have derived a modified empirical formula that can improve the accuracy of estimating the maneuverability of fishing vessels in a previous study. In this study, using the modified empirical formula, the IMO maneuverability evaluation items, the turning motion test and Z-test simulations were performed on the fisheries training vessel BAEK-KYUNG and compared with the sea trial test result to verify the validity of the modified empirical formula. In conclusion, the modified empirical formula was able to estimate quantitatively and qualitatively similar to the result of the sea trial test. Such a study on estimating the maneuverability of fishing vessels will be a good indicator for fishing vessel operators and will help them analyze marine accidents.

A Practical Approach to Mass Estimation of Loose Parts

  • Kim, Jung-Soo;Joon Lyou
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1999년도 제14차 학술회의논문집
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    • pp.274-277
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    • 1999
  • This paper is concerned with estimating the mass of a loose part in the steam generator of a nuclear power plant. Although there is the basic principle known as “Hertz Theory”for estimating mass and energy of a spherical part impacted on an infinite flat plate, the theory is not directly applicable because real plants do not comply with the underlying ideal assumptions. (Say, the steam generator is of a cylindrical and hemisphere shape.) In this work, a practical method is developed based on the basic theory and considering amplitude and energy attenuation effects. Actually, the impact waves propagating along the plate to the sensor locations become significantly different in shape and frequency spectrum from the original waveform due to the plate and surrounding conditions, distance attenuation and damping loss. To show the validity of the present mass estimation algorithm, it has been applied to the mock-up impact test data and also to real plant data. The results show better performance comparing to the conventional Hertz schemes.

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