• Title/Summary/Keyword: Accuracy Measure

검색결과 2,008건 처리시간 0.031초

Alternative accuracy for multiple ROC analysis

  • Hong, Chong Sun;Wu, Zhi Qiang
    • Journal of the Korean Data and Information Science Society
    • /
    • 제25권6호
    • /
    • pp.1521-1530
    • /
    • 2014
  • The ROC analysis is considered for multiple class diagnosis. There exist many criteria to find optimal thresholds and measure the accuracy of diagnostic tests for k dimensional ROC analysis. In this paper, we proposed a diagnostic accuracy measure called the correct classification simple rate, which is defined as the summation of true rates for each classification distribution and expressed as a function of summation of sequential true rates for two consecutive distributions. This measure does not weight accuracy across categories by the category prevalence and is comparable across populations for multiple class diagnosis. It is found that this accuracy measure does not only have a relationship with Kolmogorov - Smirnov statistics, but also can be represented as a linear function of some optimal threshold criteria. With these facts, the suggested measure could be applied to test for comparing multiple distributions.

리니어스케일을 이용한 NC 선반의 원 운동정도 측정 (Measuring of Circular Motion Accuracy of NC Lathe using Linear Scales)

  • 김영석;김재열;한지희;정정표;윤원주;송인석
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 2003년도 춘계학술대회 논문집
    • /
    • pp.1144-1149
    • /
    • 2003
  • It is very important to measure circular motion accuracy of NC lathes it affects accuracy, performance, interchange ability and quality of machine parts machined by the NC lathes in industries. So, in this study, measuring units system to measure circular motion accuracy two axes circular motion accuracy of NC lathes was composed of two optical linear scales installed on the z and x-axes of work coordinate system on NC lathe and a computer inserted with PC counter card enables to obtain measuring data. Here, ATC(Automatic Tool Changer) and moving part of linear scales are fixed with magnet bases in order to measure circular motion accuracy of the ATC of NC lathe. And next, computer software was developed in order to measure the circular motion accuracy of NC lathe under resolution of 0.1 $\mu\textrm{m}$ using two linear scales, and also computer softwares were developed so that measuring data could be modeled on plots and be analyzed numerically,

  • PDF

2차원 프로브에 의한 NC공작기계의 운동 정밀도 측정 -제2보 직선운동 정밀도 측정- (Measurement of Motion Accuracy by Two-dimensional Probe on NC Machine Tools -2nd Report, Measurement of the Linear Motion Accuracy-)

  • 전언찬;소산전중덕;제정신;각전윤일랑
    • 한국정밀공학회지
    • /
    • 제14권7호
    • /
    • pp.15-21
    • /
    • 1997
  • This paper presented a linear motion accuracy by using two-dimensional probe with the master block and the square for NC machine tools. This measuring system could be measured motion error due to numerical control system. The results of measurement and simulation for motion error were similar, and so, this system had enough accuracy to measure a linear motion accuracy for NC machine tools. The experimental results are as follows. 1. This measuring system could be measured motion error due to mumerical control system. 2. The results of measurement and simulation for motion error were similar. 3. This measuring system had enough accuracy to measure a linear motion accuracy for NC machine tools.

  • PDF

선반 주축의 회전운동 정도 측정 (Measuring of Rotational Accuracy of Lathe Spindle)

  • 김영석
    • 한국공작기계학회논문집
    • /
    • 제16권6호
    • /
    • pp.43-48
    • /
    • 2007
  • It is important to measure the rotational accuracy of lathe spindle as it affects to the qualities of all machines machined by the lathe using in industries. The bad rotational accuracy of lathe spindle are caused mainly by wearness of the spindle in using and quality of spindle when machining and using low level bearings. It occurs especially in case of lathes because the cutting force acting to work-piece act on one side to the spindle not to both sides symmetrically. Therefore in this study, constructing experimental apparatus for measuring of rotational accuracy by using eddy current type gap sensors AEC5706PS and sensors, s-06LN, data acquisition board DT9834(USB type) and software for data acquisition, DT Measure Foundry ver. 4.0.7 etc., error data acquired in the rotational accuracy test of lathe spindle are analysed in plots and statistical treatments.

오즈 곡선과 최적분류점 (Odds curve and optimal threshold)

  • 홍종선;오태규;오세현
    • 응용통계연구
    • /
    • 제34권5호
    • /
    • pp.807-822
    • /
    • 2021
  • 오즈 곡선으로 설명이 가능한 정확도 측도들을 살펴보고, 오즈 곡선의 성질을 바탕으로 대안적인 최대 사각형 정확도 측도를 제안한다. 다양한 확률분포함수와 실증예제를 고려하여 정확도 측도들에 대응하는 분류점을 구하고, 분류점을 측정하는 통계량들을 비교하면서 특징을 토론한다. 그러므로 ROC 곡선 등과 유사하게 오즈 곡선으로부터도 최적분류점들을 발견하고 설명할 수 있으며, 최대사각형 측도는 이진 분류모형의 성능을 향상시킬 수 있는 정확도 측도로 활용할 수 있다.

원자간력 현미경을 이용한 대면적 표면 형상 측정 방법 (A large surface-shape measurement method by using Atomic Force Microscope)

  • 신영현;고명준;홍성욱;권현규
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 2005년도 춘계학술대회 논문집
    • /
    • pp.1543-1546
    • /
    • 2005
  • This paper presents a method to measure a large surface shape using atomic force microscopy, which has been used mostly for measuring over very tiny surfaces. Experiments are performed to measure a step height and a slope of a test sample. The proposed method is rigorously compared with the coordinate measuring machine. The repetition accuracy and the effects of the set point are also studied. The experimental results show that the proposed method is reliable and should be effective to measure both the nano-accuracy surface profile as well as the micro-accuracy global shape of a macro/micro parts using atomic force microscope.

  • PDF

The Effects of Core Strengthening Training on Baseball Throwing

  • Lee, Han Ki;Jung, Da Eun;Lee, Jun Cheol
    • 국제물리치료학회지
    • /
    • 제7권1호
    • /
    • pp.965-971
    • /
    • 2016
  • The purpose of this study was to investigate the effects of core strengthening training on baseball throwing. A total of 14 subjects were recruited from among middle school baseball players. The main outcome measures were as follows: speed guns were used to measure the velocity of baseballs thrown; scored targets were used to measure throwing accuracy; and 50m measuring tapes were used to measure throwing distances. It was found that core strengthening training improved the velocity of baseballs thrown and throwing accuracy and distance. Thus, core strengthening training is effective for improving the throwing ability of baseball players.

NC선반의 직선 사이클 평면 위치결정 정도 측정에 관한 연구 (A Study on Measurement of Linear Cycle Plane Positioning Accuracy of NC Lathe)

  • 김영석;송인석;정정표;한지희;윤원주
    • 한국공작기계학회논문집
    • /
    • 제12권2호
    • /
    • pp.53-58
    • /
    • 2003
  • It is very important to measure linear cycle plane positioning accuracy of NC lathe as it effects all other parts of machines machined by them in industries. If the plane positioning accuracy of NC lathe is bad, the dimension accuracy and the change-ability of works will be bad in the assembly of machine parts. In this paper, computer software systems are organized to measure linear cycle plane positioning displacement of ATC(Automatic tool changer) on zx plane of NC lathe using two linear scales. And each sets of error data obtained from the test is descriptions to plots and the results of linear cycle plane positioning errors are expressed as nutriments by computer treatment.

리니어 스케일을 이용한 NC 선반의 직선 운동정도 측정 (Measuring of Linear Motion Accuracy of NC Lathe using Linear Scales)

  • 김영석;김재열;한지희;정정표;윤원주;송인석
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 2003년도 춘계학술대회 논문집
    • /
    • pp.1243-1248
    • /
    • 2003
  • It is very important to measure linear motion accuracy of NC lathe as it affects all other parts of machines machined by them in industries. If the motion accuracy of NC lathe is bad, the dimension accuracy and the change-ability of works will be bad in the assembly of machine parts. In this paper, computer software systems are organized to measure linear motion of ATC(Automatic tool changer) on zx plane of NC lathe using two linear scales and the time pulses coming out from computer in order to get data at constant time intervals from the linear scales. And each sets of error data obtained from the test is discripted to plots and the results of linear motion errors are expressed as numerics by computer treatment.

  • PDF

위상시간법에 의한 초음파전파시간의 결정에 관한 연구 (A study on the determination of Ultrasonic Travel Time by Norm Phase-Time Method)

  • 이은방
    • 한국항해학회지
    • /
    • 제18권4호
    • /
    • pp.137-146
    • /
    • 1994
  • In this paper, a new algorithm to measure the ultrasonic travel time is proposed, which is fundamental to estimate distance depth and volume in several media. Pulse wave has been used to measure travel time of transmitted signal. However, due to the characteristic of transducer and propagation, the received signal is so distorted that it is difficult to measure travel time, which is propagation, the received signal is so distorted that it is difficult to measure travel time, which is to be time difference between transmitted and received signals. In this proposed method, transmitted and received signal are transformed respectively into norm phase newly designed by this paper and displayed on phase-time curve. And travel time is simply determined by the arithmetic numerical mean of time difference at the identical norm phase on the phase-time curves of transmitted and received signals. This method has several features; firstly, travel time is calculated analytically with high accuracy by least square error method, secondly, it is useful to compare the difference of signal magnitude for time information, thirdly, noise and discrete errors are relatively small, finally, the measurement accuracy is not influenced by D.C. bias. In particular, this method is useful and applicable to measuring very short distance and sound speed with high accuracy.

  • PDF