• 제목/요약/키워드: statistical correction

검색결과 304건 처리시간 0.024초

다 축면 하지 보조기가 외반슬 교정에 미주는 효과 (A Correction Effect of Multiaxial Lower Extremity Orthosis in Patients with Genu Valgum)

  • 장인수;배성수
    • The Journal of Korean Physical Therapy
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    • 제14권3호
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    • pp.355-372
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    • 2002
  • The purpose of this study was to evaluate the effect of multiaxial lower extremity orthosis on correction of genu valgum. 20 volunteers among people visited department of Rehabilitation Medicine, chungnam national university hospital, who had been diagnosed as genu valgum without other musculoskeletal problems were included. 10 individuals(mean age: 9.gyrs) who had been taken multiaxial lower extremity orthosis at least 12month were included in experimental group and the other 10 individuals(mean age: 11.7yrs) refused taking this orthosis in the control group. We measured the Q-angle & femorotibial angle using plain roentgenogram images at visiting day and repeat same test after 1year follow up. Multiaxial lower extremity orthosis consist of proximal horizontal bar with both thigh cuff, central vertical bar and distal horizontal bar with both shoes. we narrowed inter-shoes distance from start to 6th month and inter-thigh cuff distance together with above correction for next 6month in the frontal plane and from 10th month, dorsiflexed both shoes in sagittal plane. Also, we rotate the both shoes externally and retract the proximal vertical bar every month. This orthosis have to be taken at least 4 hours during sleep. The result were as follows 1. There were no statistical significant difference in each parameter between the right and left Q-angle before multiaxial lower extremity orthosis. 2. The left Q angle reduced $-11^{\circ}$ between 1st day and after 1year follow up showed statistical significant difference between multiaxial lower extremity orthosis taking group and non-taking(p<0.001). 3. The right Q angle reduced $-13^{\circ}$ between 1st day and after 1year follow up showed statistical significant difference between multiaxial lower extremity orthosis taking group and non-taking(p<0.001). 4. There were no statistical significant difference in each parameter between the right and left femorotibial angle before multiaxial lower extremity orthosis. 5. The left femorotibial angle reduced $-10.1^{\circ}$ between 1st day and after lyear follow up showed statistical significant difference between multiaxial lower extremity orthosis taking group and non-taking(p<0.001). 6. The right femorotibial angle reduced $-11.2^{\circ}$ between 1st day and after 1year follow up showed statistical significant difference between multiaxial lower extremity orthosis taking group and non-taking(p<0.001).

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Bandwidth Efficient Adaptive Forward Error Correction Mechanism with Feedback Channel

  • Ali, Farhan Azmat;Simoens, Pieter;de Meerssche, Wim Van;Dhoedt, Bart
    • Journal of Communications and Networks
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    • 제16권3호
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    • pp.322-334
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    • 2014
  • Multimedia content is very sensitive to packet loss and therefore multimedia streams are typically protected against packet loss, either by supporting retransmission requests or by adding redundant forward error correction (FEC) data. However, the redundant FEC information introduces significant additional bandwidth requirements, as compared to the bitrate of the original video stream. Especially on wireless and mobile networks, bandwidth availability is limited and variable. In this article, an adaptive FEC (A-FEC) system is presented whereby the redundancy rate is dynamically adjusted to the packet loss, based on feedback messages from the client. We present a statistical model of our A-FEC system and validate the proposed system under different packet loss conditions and loss probabilities. The experimental results show that 57-95%bandwidth gain can be achieved compared with a static FEC approach.

Digital Holographic Microscopy with extended field of view using tool for generic image stitching

  • Stepien, Piotr;Korbuszewski, Damian;Kujawinska, Malgorzata
    • ETRI Journal
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    • 제41권1호
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    • pp.73-83
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    • 2019
  • This paper describes in detail the processing path leading to successful phase images stitching in digital holographic microscope for the extension of the field of view. It applies FIJI Grid/Collection Stitching Plugin, which is a general tool for images stitching, non-specific for phase images. The FIJI plugin is extensively supported by aberration and phase offset correction. Comparative analysis of different aberration correction methods and data processing strategies is presented, together with the critical analysis of their applicability. The proposed processing path provides good background for statistical phase analysis of cell cultures and digital phase pathology.

A Note on Parametric Bootstrap Model Selection

  • Lee, Kee-Won;Songyong Sim
    • Journal of the Korean Statistical Society
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    • 제27권4호
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    • pp.397-405
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    • 1998
  • We develop parametric bootstrap model selection criteria in an example to fit a random sample to either a general normal distribution or a normal distribution with prespecified mean. We apply the bootstrap methods in two ways; one considers the direct substitution of estimated parameter for the unknown parameter, and the other focuses on the bias correction. These bootstrap model selection criteria are compared with AIC. We illustrate that all the selection rules reduce to the one sample t-test, where the cutoff points converge to some certain points as the sample size increases.

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Seasonal cointegration for daily data

  • Song, Dae-Gun;Cho, Sin-Sup;Park, Suk-Kyung
    • 한국통계학회:학술대회논문집
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    • 한국통계학회 2005년도 춘계 학술발표회 논문집
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    • pp.13-15
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    • 2005
  • In this paper, we propose an extension of the maximum likelihood seasonal cointegration procedure developed by Johansen and Schaumburg (1999) for daily time series. We presented the finite sample distribution of the associated rank test statistics for daily data.

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INFERENCE ON THE SEASONALLY COINTEGRATED MODEL WITH STRUCTURAL CHANGES

  • Song, Dae-Gun;Cho, Sin-Sup
    • Journal of the Korean Statistical Society
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    • 제36권4호
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    • pp.501-522
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    • 2007
  • We propose an estimation procedure that can be used for detecting structural changes in the seasonal cointegrated vector autoregressive model. The asymptotic properties of the estimates and the test statistics for the parameter change are provided. A simulation example is presented to illustrate this method and its concept.

ON THE LIMITING DISTRIBUTION FOR ESTIMATE OF PROCESS CAPABILITY INDEX

  • Park, Hyo-Il;Cho, Joong-Jae
    • Journal of the Korean Statistical Society
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    • 제36권4호
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    • pp.471-477
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    • 2007
  • In this paper, we provide a new proof to correct the asymptotic normality for the estimate $\hat{C}_{pmk}\;of\;C_{pmk}$, which is one of the well-known definitions of the process capability index. Also we comment briefly on the correction of the limiting distribution for $\hat{C}_{pmk}$ and on the use of re-sampling methods for the inference of $C_{pmk}$. Finally we discuss the concept of asymptotic unbiasedness.

KOMPSAT-3 영상을 활용한 도심지 그림자 영역의 탐지 및 보정 방법 (Shadow Detection and Correction Method for Urban Area using KOMPSAT-3 Image)

  • 박숭환;이규석;정형섭
    • 대한원격탐사학회지
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    • 제33권6_3호
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    • pp.1197-1213
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    • 2017
  • 본 연구는 KOMPSAT-3 위성영상의 도심지역에 나타나는 그림자 영역을 보정하기 위하여 실시되었다. 이를 위하여, 인공구조물에 의해 나타나는 그림자 영역에 대한 특성을 분석하여 그림자 영역을 본그림자와 반그림자로 구분하였으며, 각각의 영역을 정확하게 탐지하여 오분류의 가능성을 줄이기 위한 방법을 제시하였다. 또한 본그림자 영역으로부터 반그림자 영역과 비그림자 영역을 각각 탐지하였으며, 선형상관보정방법과 과보정 저감계수를 적용하여 탐지된 그림자 영역에 대한 보정을 수행하였다. 그 결과 시각적으로 자연스러운 보정된 영상을 획득할 수 있었으며, 프로파일 분석을 통하여 정량적으로도 그림자 영역이 효과적으로 보정됨을 확인하였다.

지역 위성항법시스템 항법메시지 및 광역 보정정보 성능 분석을 위한 MATLAB GUI 기반 소프트웨어 개발 (Development of MATLAB GUI-based Software for Performance Analysis of RNSS Navigation Message and WAD-RNSS Correction)

  • 박재욱;김부겸;기창돈;김동욱
    • 한국항행학회논문지
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    • 제27권5호
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    • pp.510-518
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    • 2023
  • 본 논문에서는 지역 위성항법시스템의 항법메시지와 광역 보정정보 성능 분석을 위해 MATLAB GUI (graphic user interface) 기반으로 개발된 소프트웨어에 대해 소개한다. 본 소프트웨어는 한반도 및 주변 지역에 서비스를 제공하는 가상의 지역 위성항법시스템의 감시국 및 기준국 배치에 따른 항법메시지와 광역 보정정보의 위성 궤도/시각 관련 성능을 분석하기 위해 개발되었다. 본 소프트웨어 구동 시 항법메시지 및 광역 보정정보가 MATLAB 파일 형식으로 출력된다. 개발된 소프트웨어의 출력을 검증한 결과, 궤도 및 시계 예측 오차가 통계적 예측에 부합하며, 파라미터 피팅 오차가 cm 수준임을 확인하였다. 또한, 광역 보정정보가 측정치 차원의 오차를 81.9% 개선함을 확인하여 유효한 항법메시지 및 광역 보정정보 성능 분석이 가능함을 확인하였다.

금융시장 전염 동적 검정 (Dynamic analysis of financial market contagion)

  • 이희수;김태윤
    • 응용통계연구
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    • 제29권1호
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    • pp.75-83
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    • 2016
  • 본 연구에서는 금융시장 통합화에 따른 금융 시장 전염을 생물학적 전염개념에 기초하여 분석하는 검정 방법론을 제시하였다. 금융 시장 통합화를 측정하기 위하여 U-통계량을 사용하였고, 금융 시장 전염 검정을 위하여 단일방정식 오차수정 모형을 중심으로 잠재 요인모형, 분위수 회귀모형과 런검정을 사용하였다. 시뮬레이션결과 단일방정식 오차수정 모형이 자기상관을 갖는 오차항을 포함한 선형 회귀모형에서 비교적 높은 수준의 적합도를 일관성 있게 보여 주고 있다.