• 제목/요약/키워드: intuitive estimation

검색결과 50건 처리시간 0.026초

기본물리량 어림의 정확성 및 방법에 대한 탐색 (Exploring the Accuracy and Methods of Estimation on Base Physical Quantities)

  • 송진웅;김혜선
    • 한국과학교육학회지
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    • 제21권1호
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    • pp.76-88
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    • 2001
  • 본 연구는 길이, 질량, 시간, 온도와 같은 일부 기본 물리량에 대한 사람들의 어림의 정확성과 방법에 대해 탐색하였다. 대학 물리교육과의 구성원(학부 1학년부터 교수까지) 중 임의로 선정된 총 40명이 2종류의 대상물 세트에 대해 직관적 어림과 조작적 어림 활동을 수행하였다. 직관적 어림에서는 참여자들이 각 대상물을 직면하자마자 해당 물리량의 값을 어림하였으며, 조작적 어림에서는 별도의 대상물에 대해서 충분한 시간을 두고 다양한 가용한 방법들을 (예컨대, 길이를 어림하기 위해 연필을 활용하거나 시간을 어림하기 위해 맥박을 세거나) 동원하여 어림하였다. 연구의 결과는 다음과 같이 요약될 수 있겠다: (1) 길이, 질량, 온도에 대해서는 직관적 어림이 더 정확하였으나 시간에 대해서는 조작적 어림이 더 정확하였다. (2) 물리학에 대한 경험의 정도와 어림의 정확성 사이에는 정적인 상관관계가 존재하지 않았다. (3)일반적으로 길이에 대한 어림이 가장 정확하였으며 질량에 대한 어림은 가장 부정확하였다. (4) 사람들은 조작적 어림을 위해서 스스로의 다양한 방법을 사용하였는데, 예컨대 대상물 주변의 각종 사물들을 활용하거나 특정한 값을 갖는 마음 속의 측정 단위(즉, 30cm, 50cm, 1kg, 1근, 1초 등)들을 적용하였다.

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Estimation of Treatment Effect for Bivariate Censored Survival Data

  • Ahn, Choon-Mo;Park, Sang-Gue
    • Communications for Statistical Applications and Methods
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    • 제10권3호
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    • pp.1017-1024
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    • 2003
  • An estimation problem of treatment effect for bivariate censored survival data is considered under location shift model between two sample. The proposed estimator is very intuitive and can be obtained in a closed form. Asymptotic results of the proposed estimator are discussed and simulation studies are performed to show the strength of the proposed estimator.

A study on robust regression estimators in heteroscedastic error models

  • Son, Nayeong;Kim, Mijeong
    • Journal of the Korean Data and Information Science Society
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    • 제28권5호
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    • pp.1191-1204
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    • 2017
  • Weighted least squares (WLS) estimation is often easily used for the data with heteroscedastic errors because it is intuitive and computationally inexpensive. However, WLS estimator is less robust to a few outliers and sometimes it may be inefficient. In order to overcome robustness problems, Box-Cox transformation, Huber's M estimation, bisquare estimation, and Yohai's MM estimation have been proposed. Also, more efficient estimations than WLS have been suggested such as Bayesian methods (Cepeda and Achcar, 2009) and semiparametric methods (Kim and Ma, 2012) in heteroscedastic error models. Recently, Çelik (2015) proposed the weight methods applicable to the heteroscedasticity patterns including butterfly-distributed residuals and megaphone-shaped residuals. In this paper, we review heteroscedastic regression estimators related to robust or efficient estimation and describe their properties. Also, we analyze cost data of U.S. Electricity Producers in 1955 using the methods discussed in the paper.

FUZZY ESTIMATION OF VEHICLE SPEED USING AN ACCELEROMETER AND WHEEL SENSORS

  • HWANG J. K.;SONG C. K.
    • International Journal of Automotive Technology
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    • 제6권4호
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    • pp.359-365
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    • 2005
  • The absolute longitudinal speed of a vehicle is estimated by using data from an accelerometer of the vehicle and wheel speed sensors of a standard 50-tooth antilock braking system. An intuitive solution to this problem is, 'When wheel slip is low, calculate the vehicle velocity from the wheel speeds; when wheel slip is high, calculate the vehicle speed by integrating signal of the accelerometer.' The speed estimator weighted with fuzzy logic is introduced to implement the above concept, which is formulated as an estimation method. And the method is improved through experiments by how to calculate speed from acceleration signal and slip ratios. It is verified experimentally to usefulness of estimation speed of a vehicle. And the experimental result shows that the estimated vehicle longitudinal speed has only a $6\%$ worst-case error during a hard braking maneuver lasting a few seconds.

물리적 인간-기계 상호작용을 위한 표면 근전도 신호 기반의 어깨 굴곡 토크 및 각도 추정 (Estimation of Shoulder Flexion Torque and Angle from Surface Electromyography for Physical Human-Machine Interaction)

  • 박기한;이동주;김정
    • 한국정밀공학회지
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    • 제28권6호
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    • pp.663-669
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    • 2011
  • This paper examines methods to estimate torque and angle in shoulder flexion from surface electromyography(sEMG) signals for intuitive and delicate control of robotic assistance device. Five muscles on the upper arm, three for shoulder flexion and two for shoulder extension, were used to offer favorable sEMG recording conditions in the estimation. The methods tested were the mean absolute value (MAV) with linear regression and the artificial neural network (ANN) method. An optimal condition was sought by varying combination of muscles used and the parameters in each method. The estimation performance was evaluated using the correlation values and normalized root mean square error values. In addition, we discussed their possible use as an estimation of motion intent of a user or as a command input in a physical human-machine interaction system.

철도사업에의 직관적 타당성 평가모형 적용 (The application of the Intuitive Method to Evaluate Feasibilities of Railway Project)

  • 김현웅;현재명
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2010년도 춘계학술대회 논문집
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    • pp.437-441
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    • 2010
  • The SOC project such as road and railway performs a preliminary feasibility study according to the priority of the individual projects after establishing the master plans. For a preliminary feasibility study, feasibility evaluation should be performed according to the transport demand estimation and economic analysis. The feasibility of individual project will be performed by focussing on the results of analyzing economic feasibility. In case that analysis of the traffic demand and the economic feasibility every phase is performed, a lot of time and expense will be required in the course of promoting projects. So this study could give help to determine the priority of the project by intuitive method only in the phase to establish the master plan and a preliminary feasibility study.

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복합용도 개발 도시재생 사업에서의 단위 공간 기반 개산견적 모델링 가이드 제안 - ○○시 ○○역 복합환승센터 사례를 중심으로 - (A Proposal of Modeling Guide of the Unit Space-based Preliminary Cost Estimation in Urban Renewal Mix-Used Development - Case Study on ○○ Transfer Station Complex -)

  • 강신엽;안재홍;김주형
    • 한국BIM학회 논문집
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    • 제3권1호
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    • pp.11-20
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    • 2013
  • Mix-used development in urban renewal project is done to effectively utilize the limited downtown. Generally unlike a single project, It features placing a large number of different facilities(residential, commercial, business, cultural, etc.) which is each other organically linked. The purpose of this study is to suggest the method of modeling guide for 3D preliminary cost estimation considering visual and intuitive judgement of space in mix-used development Urban Renewal project. In this research, introducing SME(Standard Module and Element) breakdown structure, FID(Finish Identity) for estimating building space unit-based quantity take off was implemented. It could narrow the discrepancy of opinion between the stakeholders with more accurate cost-estimates, comparing to the traditional methods.

Control of Humanoid Robots Using Time-Delay-Estimation and Fuzzy Logic Systems

  • Ahn, Doo Sung
    • 드라이브 ㆍ 컨트롤
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    • 제17권1호
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    • pp.44-50
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    • 2020
  • For the requirement of accurate tracking control and the safety of physical human-robot interaction, torque control is basically desirable for humanoid robots. Because of the complexity of humanoid robot dynamics, the TDC (time-delay control) is practical because it does not require a dynamic model. However, there occurs a considerable error due to discontinuous non-linearities. To solve this problem, the TDC-FLC (fuzzy logic compensator) is applied to humanoid robots. The applied controller contains three factors: a TDE (time-delay estimation) factor, a desired error dynamic factor, and FLC to suppress the TDE error. The TDC-FLC is easy to execute because it does not require complicated humanoid dynamic calculations and the heuristic fuzzy control rules are intuitive. TDC-FLC is implemented on the whole body of a humanoid, not on biped legs even though it is performed by a virtual humanoid robot. The simulation results show the validity of the TDC-FLC for humanoid robots.

Line of Sight Vector Estimation using UWB for Augmented Reality Based Indoor Location Monitoring System

  • Chun, Sebum;Seo, Jae-Hee;Lee, Sangwoo;Heo, Moon-Beom
    • Journal of Positioning, Navigation, and Timing
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    • 제5권3호
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    • pp.145-156
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    • 2016
  • A variety of methods for indoor positioning systems have been underway to ensure the safety of emergency rescuers who are working in dangerous situations such as fire fighters. However, since most systems display locations of rescue workers in two-dimension (2D)-based maps, it is difficult for a commander located in the outside to recognize locations of rescuers inside the building intuitively. An augmented reality (AR)-based indoor positioning monitoring system can display locations of rescuer inside the building that can be seen by commanders to help intuitive recognition of positioning. To monitor AR-based indoor positioning, it is necessary to have an estimation technique of line of sight vector of observers. In the present study, an estimation technique of a line of sight vector using ultra-wide band tranceiver installed inside the indoor to trace locations is presented.

Modeling and parameter estimation of a fish-drying control system

  • Sakai, Y.;Wada, K.;Nakamura, H.
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 19-21 Oct. 1992
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    • pp.440-445
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    • 1992
  • The major purpose here is to estimate the drying time required in the fish-drying process employed. The basic element of the prediction of the drying time is the model or the equation, which governs the change in weight. By an intuitive consideration on the mechanism of dehydration, a mathematical model of the fish-drying process is built, which is described by a system of linear differential equations. Further, a modified system of linear differential equations for a model of drying is also proposed for more accurate estimation. The parameter estimation of this system of equations provides the prediction of necessary drying time.

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