• 제목/요약/키워드: Statistical comparisons

검색결과 394건 처리시간 0.027초

다중비교를 이용한 선삭가공시 절삭유량에 따른 온도변화분석 (Temperature analysis of each coolant level in turning by a multiple comparison)

  • 박태준;양승한;이영문;김희술
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2001년도 춘계학술대회 논문집
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    • pp.1033-1036
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    • 2001
  • The object of this paper is to find out a coolant level, which is economic and similar to the conventional level, high level, in cutting temperature. For this, new coolant level, called a low level, was proposed, which is about 1/4 of conventional level. And the cutting temperature of each coolant level in turning was analyzed using statistical method. Firstly, it was analyzed that the temperature mean of each coolant level is not equal by ANOVA-test. Secondly by Tukey's HSD, one of multiple comparisons, it was analyzed that the temperature mean of low level is similar to that of high level and different from that of none level.

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POLARIZATION OBSERVATIONS OF BACKGROUND RADIO SOURCES SEEN THROUGH THE SUPERNOVA REMNANT S 147

  • Kim, Kwang-Tae
    • 천문학회지
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    • 제21권2호
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    • pp.133-153
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    • 1988
  • Linear polarization has been measured for fifteen extragalactic radio sources in the field of supernova remnant S 147. These observations were made at 4885, 4835, 1665, 1515, 1465, and 1385 MHz using the Very Large Array, primarily to determine unambiguous Rotation Measures (RM) of the sources. This yields a total of 11 new RM sources. Comparisons of a sample of sources which are seen through S 147 were made with sources located farther away. The result tentatively indicates that the distribution of the rotation measure of the former population is broadened, with more than a 85% level of confidence. This constitutes evidence that there is a SNR contribution to rotation measure in sources seen through the SNR. Limits on this RM contribution are statistically at 30 < | RM | < 70 rad $m^{-2}$ with a 85% statistical level of confidence. These result imply the magnetic field in the rim of S 147 has strength 10 microguass if the electron density is $1\;cm^{-3}$.

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32채널 뇌파 및 뇌유전발전위 Mapping 시스템 (32-Channel EEG and Evoked Potential Mapping System)

  • 안창범;박대준
    • 대한의용생체공학회:의공학회지
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    • 제17권2호
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    • pp.179-188
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    • 1996
  • A clinically oriented 32-channel electroencephalogram (EEG) and evoked potential (EP) mapping system has been developed EEG and EP signals acquired from 32-channel electrodes attached on the heroid surface are amplified by a pre-amplifier which is separated from main amplifier and is located near the patient to reduce signal attenuation and noise contamination between electrodes and the amplifier. The amplified signals are further amplified by a main amplifier where various filtering and gain contr61 are achieved An automatic artifact rejection scheme is employed using neural network-based EEG and artifact classifier, by which examination time is substantially reduce4 The continuously measured EEG sigrlals are used for spectral mapping, and auditory and visual evoked potentials measured in synchronous to the auditory and visual stimuli are used for temporal evoked potential mapping. A user-friendly graphical interface based on the Microsoft Window 3.1 is developed for the operation of the system. Statistical databases for comparisons of group and individual are included to support a statistically-based diagnosis.

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표본크기가 다른 정규모집단의 평균에 대한 부분집합선택절차론의 성질과 비교연구 (Comparisons of some subset selection procedures for K normal populations with unequal sample size)

  • 손중권;김소연;김영훈
    • 응용통계연구
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    • 제3권1호
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    • pp.79-87
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    • 1990
  • 표본의 크기가 동일하지 않으면서 등분산이 기지 또는 미지인 경우 k개의 정규모집단의 평균에 대한 부분집합선택절차론은 여러 사람들에 연구되었으나 제안된 부분집합선택절차들의 성질과 효율성을 비교한 결과가 미흡하다. 본 고에서는 제안된 특성을 조사하고 여러 가지 형태에서 효율성을 비교하였다.

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Investigation of Crustal Deformation due to the Kyungju Earthquake in 2016

  • Hong, Chang-Ki
    • 한국측량학회지
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    • 제34권6호
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    • pp.591-596
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    • 2016
  • The $M_w=5.8$ Kyungju (South Korea) earthquake took place on 12 September 2016. This event may cause deformation around Kyungju city, located in the southeastern part of the Korean peninsula. In this study, GPS data was collected from the 17 Korean CORS and processed to determine the deformation. Minimum constraint solutions, to avoid the network distortion, are obtained and an S-transformation is applied to the coordinate difference vector and its covariance matrix for comparisons. In the final step, a statistical test is performed to determine the deformation due to the Kyungju earthquake. Based on the results, it was found that there is no significant deformation around Kyungju city. Hence, it can be said that the re-measurement or re-establishment of the geodetic control points in South Korea is not required.

가정학 연구에서 활용되는 관능검사에 대한 신뢰도 평가방법에 관한 연구 (Improvement of Reliability in the Sensory Evaluation for Home Economics Research)

  • 위은하;박정수
    • 한국가정과학회지
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    • 제3권2호
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    • pp.90-100
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    • 2000
  • Statistical reliability in the sensory evaluation measures the agreement of judgements for several observers. Kendall's coefficient of concordance for multiple rankings. and coefficient of consistence and coefficient of agreement for paired comparisons are frequently used as the standard reliability measures. The main idea and the computational formula of these coefficients in various situations are explained in detail with some real (cloth designing) examples. Moreover a user-friendly computer program called as MultPair is introduced. We expect that this expository paper and the computer program give a practical help to the researchers who use the sensory evaluation techniques.

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R의 분류방법을 이용한 신용카드 승인 분석 비교 (A Comparison of Classification Methods for Credit Card Approval Using R)

  • 송종우
    • 품질경영학회지
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    • 제36권1호
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    • pp.72-79
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    • 2008
  • The policy for credit card approval/disapproval is based on the applier's personal and financial information. In this paper, we will analyze 2 credit card approval data with several classification methods. We identify which variables are important factors to decide the approval of credit card. Our main tool is an open-source statistical programming environment R which is freely available from http://www.r-project.org. It is getting popular recently because of its flexibility and a lot of packages (libraries) made by R-users in the world. We will use most widely used methods, LDNQDA, Logistic Regression, CART (Classification and Regression Trees), neural network, and SVM (Support Vector Machines) for comparisons.

분산분석 (The Application of Analysis of Variance (ANOVA))

  • 박선일;오태호
    • 한국임상수의학회지
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    • 제27권1호
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    • pp.71-78
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    • 2010
  • Analysis of variance (ANOVA) is a method to analyze the data from the experimental designs comparing two or more groups or treatments at the same time, and is the most effective tool of analyzing more complex data sets with different source of variations. This article describes the logic of ANOVA, the application of the method to the analysis of a simple data set, and the methods available for performing planned or post hoc multiple comparisons between the treatments means. In addition, the common misuse of the techniques is also discussed to emphasize that an inappropriate statistical analysis is potentially far more harmful than poorly conducted research. Lastly, an example is given for illustration purposes.

기상수치모의와 원격탐사 해상풍 축출결과 비교 (Comparison between Numerical Weather Prediction and Offshore Remote-Sensing Wind Extraction)

  • 황효정;김현구;경남호;이화운;김동혁
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2008년도 추계학술대회 논문집
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    • pp.318-320
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    • 2008
  • Offshore remote-sensing wind extraction using SAR satellite image is an emerging and promising technology for offshore wind resource assessment. We compared our numerical weather prediction and offshore wind extraction from ENVISAT images around Korea offshore areas. A few comparison sets showed good agreement but more comparisons are required to draw application guideline on a statistical basis.

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후두질환에 대한 술전 술후 음성의 음향적 특성비교 분석 (Analysis and Comparisons of Acoustical Characteristics of Pathologic Voice before and after Surgery)

  • 김대현;조철우;백무진;왕수건
    • 음성과학
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    • 제7권3호
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    • pp.285-294
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    • 2000
  • In this paper the acoustic characteristics of pathological voice, which are measured before and after surgical operation, are compared. This experiment is conducted for the purpose of predicting patients' speech after operation. The voices are recorded from the same patients. Jitter, shimmer and other parameters are. computed and their statistical characteristics are compared. Also spectral changes, such as formant frequency shift and spectral slope change, are compared. From the experimental results, it is verified that not only source characteristics but also vocal tract components vary. And this indicates that the modification of source parameters are not enough for the prediction. Also the result indicates that the operation causes change to both the physical shape of vocal folds and the manner of articulation.

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