• 제목/요약/키워드: threshold methods

검색결과 1,483건 처리시간 0.033초

Immediate Effects of Myofascial Release Using Vibration Foam Rolling Methods on Hamstrings Range of Motion, Flexibility, Pressure Pain Thresholds and Dynamic Balance

  • Kim, Ho;Shin, Wonseob
    • 국제물리치료학회지
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    • 제11권2호
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    • pp.2042-2051
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    • 2020
  • Background: Many trials have been conducted the methods and types of intervention of form rollers, but no research has been done yet that mixes the methods and types of intervention. Objectives: To analyze the effects of myofascial release on the improvement of range of motion (ROM), flexibility, pain pressure threshold, and balance. Design: Randomized controlled trial. Methods: All subjects measured ROM, flexibility, pressure pain threshold, and dynamic balance by pre-test. After pre-test, subjects were randomized that static-vibration foam rolling group (n=12), dynamic-vibration foam rolling group (n=12), general foam rolling group (n=12). For the intervention, 3 sets of 90 seconds were applied to each group, and rest time was set to 60 seconds between sets. In the post-test and follow-up test after 10 minutes, all three groups were measured the ROM, flexibility, pressure pain threshold, and dynamic balance. Results: The results of comparing ROM, flexibility, pressure pain thresholds, dynamic balance ability appeared higher significant difference in the pre-post-10 minutes follow up test in comparison between time in the intragroup (P<.001). As a result of comparing the change of pre-post-10 minutes follow up, static vibration foam rolling showed higher significant difference compared to control groups (P<.001). Conclusion: Through this study, when foam rolling is applied within the same intervention time, static foam rolling can be expected to have a better effect than the existing dynamic foam rolling as well as vibration foam roller can expect better effect than general foam rolling.

잡음 제거를 위한 웨이브렛기반 알고리즘에 관한 연구 (A Study on the Wavelet-based Algorithm for Noise Cancellation)

  • 배상범;김남호
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2005년도 춘계종합학술대회
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    • pp.524-527
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    • 2005
  • 최근, 사회는 고도의 디지털 정보화 시대로 급속히 발전하고 있다. 그러나 여전히 신호를 처리하는 과정에서 여러 가지 원인에 의해 잡음이 발생하고 있으며, 이러한 잡음들을 제거하기 위한 다양한 방법들이 연구되고 있다. 잡음을 제거하기 위해 기존에 FFT와 STFT 등이 있었으나, 신호에 대한 시간정보를 알 수 없고 시간-주파수 국부성이 상충관계를 갖는다. 따라서 이러한 한계를 극복하기 위해, 다중해상도 해석이 가능한 웨이브렛기반의 잡음 제거 기법들이 신호처리 분야에서 응용되고 있다. 그러나 threshold와 상관관계를 이용한 잡음 제거 방법은 잡음의 통계적 특징만을 반영함에 따라, 많은 잡음들이 edge로써 판단될 수 있으며, AWGN과 임펄스 잡음을 동시에 제거하기 위한 방법을 제공하지 않는다. 따라서 본 논문에서는 웨이브렛기반의 새로운 잡음 제거 방법을 제시하여, 기존의 방법들과 비교하였다.

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An Effective Denoising Method for Images Contaminated with Mixed Noise Based on Adaptive Median Filtering and Wavelet Threshold Denoising

  • Lin, Lin
    • Journal of Information Processing Systems
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    • 제14권2호
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    • pp.539-551
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    • 2018
  • Images are unavoidably contaminated with different types of noise during the processes of image acquisition and transmission. The main forms of noise are impulse noise (is also called salt and pepper noise) and Gaussian noise. In this paper, an effective method of removing mixed noise from images is proposed. In general, different types of denoising methods are designed for different types of noise; for example, the median filter displays good performance in removing impulse noise, and the wavelet denoising algorithm displays good performance in removing Gaussian noise. However, images are affected by more than one type of noise in many cases. To reduce both impulse noise and Gaussian noise, this paper proposes a denoising method that combines adaptive median filtering (AMF) based on impulse noise detection with the wavelet threshold denoising method based on a Gaussian mixture model (GMM). The simulation results show that the proposed method achieves much better denoising performance than the median filter or the wavelet denoising method for images contaminated with mixed noise.

An Optimal Thresholding Method for the Voxel Coloring in the 3D Shape Reconstruction

  • Ye, Soo-Young;Kim, Hyo-Sung;Yi, Young-Youl;Nam, Ki-Gon
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2005년도 ICCAS
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    • pp.1695-1700
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    • 2005
  • In this paper, we propose an optimal thresholding method for the voxel coloring in the reconstruction of a 3D shape. Our purposed method is a new approach to resolve the trade-off error of the threshold value on determining the photo-consistency in the conventional method. Optimal thresholding value is decided to compare the surface voxel of photo-consistency with inside voxel on the optic ray of the center camera. As iterating the process of the voxels, the threshold value is approached to the optimal value for the individual surface voxel. And also, graph cut method is reduced to the surface noise on eliminating neighboring voxel. To verify the proposed algorithm, we simulated in the virtual and real environment. It is advantaged to speed up and accuracy of a 3D face reconstruction by applying the methods of optimal threshold and graph cut as compare with conventional algorithms.

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염화물 혼입 콘크리트 중의 철근부식 임계 염화물량 (Threshold Chloride Contents of Steel Corrosion in Concrete Containing Chloride)

  • 문한영;김성수;김홍삼;이승태;김은호
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2000년도 가을 학술발표회논문집(I)
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    • pp.395-398
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    • 2000
  • Recently, increasement of usage contents of sea sand in constructing concrete structures due to insufficiency of high quality river sand, led to many studies for steel corrosion and control methods on it in concrete. But, domestic studies for threshold chloride contents of steel corrosion are not so many as those of foreign states. In this study, the electrochemical test as half cell potential measurement and linear polarization method to estimate the corrosion of steel in contents mixed with several levels chloride contents was performed, thereby, pre-mixed chloride were compared with results measured quantitatively for steel corrosion. And, based on these data, a trial to determine threshold chloride contents of steel corrosion was made.

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새로운 회로기술을 이용한 고정밀 Matching-Free MOSFET 문턱전압 추출 (An Accurate and Matching-Free MOSFET's Threshold Voltage Extraction Using New Novel Circuit Thencique)

  • 유종근;신남승;박종태
    • 전자공학회논문지A
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    • 제32A권1호
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    • pp.166-178
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    • 1995
  • An accurate threshold voltage extraction scheme for MOS transistors is presented. In contrast to alternative methods recently reported in the literature, this scheme does not need matched replica of the transistor under test, and thus can be applied more effectively and accurately to raal-time on-chip applications where threshold voltage measurements are required for many transistors with various geometries and bias conditions. The proposed scheme is accurately implemented in a matching-free way using a ratio-indepentent switched-capacitor subtracting amplifier and a dynamic current mirror. Nonideal effects associated with these circuits have been investiggated and compensated.

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Segmentation and Recognition of Korean Vehicle License Plate Characters Based on the Global Threshold Method and the Cross-Correlation Matching Algorithm

  • Sarker, Md. Mostafa Kamal;Song, Moon Kyou
    • Journal of Information Processing Systems
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    • 제12권4호
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    • pp.661-680
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    • 2016
  • The vehicle license plate recognition (VLPR) system analyzes and monitors the speed of vehicles, theft of vehicles, the violation of traffic rules, illegal parking, etc., on the motorway. The VLPR consists of three major parts: license plate detection (LPD), license plate character segmentation (LPCS), and license plate character recognition (LPCR). This paper presents an efficient method for the LPCS and LPCR of Korean vehicle license plates (LPs). LP tilt adjustment is a very important process in LPCS. Radon transformation is used to correct the tilt adjustment of LP. The global threshold segmentation method is used for segmented LP characters from two different types of Korean LPs, which are a single row LP (SRLP) and double row LP (DRLP). The cross-correlation matching method is used for LPCR. Our experimental results show that the proposed methods for LPCS and LPCR can be easily implemented, and they achieved 99.35% and 99.85% segmentation and recognition accuracy rates, respectively for Korean LPs.

A Mask-based Gaussian Noise Removal Algorithm in Spatial Space

  • Seo, Hyun-Soo;Kim, Nam-Ho
    • Journal of information and communication convergence engineering
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    • 제5권3호
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    • pp.259-264
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    • 2007
  • According to the development and wide use of broad band internet etc., diverse application technologies using large capacity data such as images have been progressed and in these systems, for accurate acquisition and precise applications of an original signal, the degradation phenomenon generated in the transmission process etc. should be removed. Noises have become known as the main cause of the degradation phenomenon and especially Gaussian noise represents characteristics occurring dependently in image signals and degrades detail information such as edge. In this paper, we removed Gaussian noise using a subdivided nonlinear function according to a threshold value and analyzed the histogram acquired from an edge image to establish a threshold value adaptively, and strengthened detail information of image by using the postprocessing. In simulation results, the proposed method represented excellent performance from comparison of MSE with existing methods.

미각 이상 환자의 미각 역치 검사에 관한 증례 보고 (A Case Report on the Taste Threshold Tests in Two Patients with Taste Disorder)

  • 홍주희;오정규;고홍섭
    • Journal of Oral Medicine and Pain
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    • 제26권2호
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    • pp.127-131
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    • 2001
  • The authors performed the taste threshold tests in two patients complaining taste problem who visited the Department of Oral Diagnosis, Seoul National University Dental Hospital. The taste thresholds were determined using a concentration series of five tastants, sucrose ( sweet ), NaCl ( salty ), citric acid ( sour ), quinine hydrochloride ( bitter ) and monosodium glutamate ( umami ). The taste solutions were diluted by half quarter logarithmic steps. The two patients showed higher taste thresholds level than normal but the taste threshold results did not coincide with the patients appeal. Further researches are needed for developing simple and precise diagnostic methods which can be applied to the patients with taste disorder.

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컷 검출을 위한 동적 임계값 기법 (Dynamic Threshold Method For Cut Detection)

  • 윤인구;김우생
    • 한국정보처리학회논문지
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    • 제6권7호
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    • pp.1955-1961
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    • 1999
  • 비디오 데이터는 비정형 데이터이고 정보의 양이 방대하기 때문에 내용기반 검색 방법이 필요하다. 비디오 데이터의 내용기반 검색을 위해서는 동영상 데이터의 색인이 필요한데, 일반적으로 비디오 색인을 하기 위한 시작점은 컷 검출이다. 본 논문에서는 컷 검출의 효율성을 향상시키기 위해서 컷 검출 과정 중 임계값이 동적으로 변화하는 동적 임계값 기법을 제안한다. 구현과 실험을 통하여 제안하는 방법이 기존의 방법보다 효율적임을 보였다. 6a A content-based search method is required for video which has an unformatted and huge size of data. The index technique is necessary for the content-based search of the video data. The first step of the video indexing is a cut detection. We propose a dynamic threshold method which changes a threshold value during the cut detection process. We demonstrate that the proposed method is more efficient than the existing methods.

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