• Title/Summary/Keyword: mean-shift algorithm

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Blood Pressure Simulation using an Arterial Pressure-volume Model

  • Yoon, Sang-Hwa;Kim, Jae-Hyung;Ye, Soo-Young;Kim, Cheol-Han;Jeon, Gye-Rok
    • Transactions on Electrical and Electronic Materials
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    • v.9 no.1
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    • pp.38-43
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    • 2008
  • Using an arterial pressure-volume (APV) model, we performed an analysis of the conventional blood pressure estimation method using an oscillometric sphygmomanometer with computer simulation. Traditionally, the maximum amplitude algorithm (MAA) has been applied to the oscillation waveforms of the APV model to obtain the mean arterial pressure and the characteristic ratio. The estimation of mean arterial pressure and characteristic ratio was significantly affected by the shape of the blood pressure waveforms and the cutoff frequency of high-pass filter (HPF) circuitry. Experimental errors result from these effects when estimating blood pressure. To determine an algorithm independent of the influence of waveform shapes and parameters of HPF, the volume oscillation of the APV model and the phase shift of the oscillation with fast Fourier transform (FFT) were tested while increasing the cuff pressure from 1 mmHg to 200 mmHg (1 mmHg/s). The phase shift between ranges of volume oscillation was then only observed between the systolic and the diastolic blood pressures. The same results were obtained from simulations performed on two different arterial blood pressure waveforms and one hyperthermia waveform.

Economic Design of Three-Stage $\bar{X}$ Control Chart Based on both Performance and Surrogate Variables (성능변수와 대용변수를 이용한 3단계 $\bar{X}$ 관리도의 경제적 설계)

  • Kwak, Shin-Seok;Lee, Jooho
    • Journal of Korean Society for Quality Management
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    • v.44 no.4
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    • pp.751-770
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    • 2016
  • Purpose: Two-stage ${\bar{X}}$ chart is a useful tool for process control when a surrogate variable may be used together with a performance variable. This paper extends the two-stage ${\bar{X}}$ chart to a three stage version by decomposing the first stage into the preliminary stage and the main stage. Methods: The expected cost function is derived using Markov-chain approach. The optimal designs are found for numerical examples using a genetic algorithm combined with a pattern search algorithm and compared to those of the two-stage ${\bar{X}}$ chart. Sensitivity analysis is performed to see the parameter effects. Results: The proposed design outperforms the optimal design of the two-stage ${\bar{X}}$ chart in terms of the expected cost per unit time unless the correlation between the performance and surrogate variables is modest and the shift in process mean is smallish. Conclusion: Three-stage ${\bar{X}}$ chart may be a useful alternative to the two-stage ${\bar{X}}$ chart especially when the correlation between the performance and surrogate variables is relatively high and the shift in process mean is on the small side.

An Automatic Urban Function District Division Method Based on Big Data Analysis of POI

  • Guo, Hao;Liu, Haiqing;Wang, Shengli;Zhang, Yu
    • Journal of Information Processing Systems
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    • v.17 no.3
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    • pp.645-657
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    • 2021
  • Along with the rapid development of the economy, the urban scale has extended rapidly, leading to the formation of different types of urban function districts (UFDs), such as central business, residential and industrial districts. Recognizing the spatial distributions of these districts is of great significance to manage the evolving role of urban planning and further help in developing reliable urban planning programs. In this paper, we propose an automatic UFD division method based on big data analysis of point of interest (POI) data. Considering that the distribution of POI data is unbalanced in a geographic space, a dichotomy-based data retrieval method was used to improve the efficiency of the data crawling process. Further, a POI spatial feature analysis method based on the mean shift algorithm is proposed, where data points with similar attributive characteristics are clustered to form the function districts. The proposed method was thoroughly tested in an actual urban case scenario and the results show its superior performance. Further, the suitability of fit to practical situations reaches 88.4%, demonstrating a reasonable UFD division result.

Two Phase Heuristic Algorithm for Mean Delay constrained Capacitated Minimum Spanning Tree Problem (평균 지연 시간과 트래픽 용량이 제한되는 스패닝 트리 문제의 2단계 휴리스틱 알고리즘)

  • Lee, Yong-Jin
    • The KIPS Transactions:PartC
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    • v.10C no.3
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    • pp.367-376
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    • 2003
  • This study deals with the DCMST (Delay constrained Capacitated Minimum Spanning Tree) problem applied in the topological design of local networks or finding several communication paths from root node. While the traditional CMST problem has only the traffic capacity constraint served by a port of root node, the DCMST problem has the additional mean delay constraint of network. The DCMST problem consists of finding a set of spanning trees to link end-nodes to the root node satisfying the traffic requirements at end-nodes and the required mean delay of network. The objective function of problem is to minimize the total link cost. This paper presents two-phased heuristic algorithm, which consists of node exchange, and node shift algorithm based on the trade-off criterions, and mean delay algorithm. Actual computational experience and performance analysis show that the proposed algorithm can produce better solution than the existing algorithm for the CMST problem to consider the mean delay constraint in terms of cost.

Equalizationof nonlinear digital satellite communicatio channels using a complex radial basis function network (Complex radial basis function network을 이용한 비선형 디지털 위성 통신 채널의 등화)

  • 신요안;윤병문;임영선
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.9
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    • pp.2456-2469
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    • 1996
  • A digital satellite communication channel has a nonlinearity with memory due to saturation characeristis of the high poer amplifier in the satellite and transmitter/receiver linear filter used in the overall system. In this paper, we propose a complex radial basis function network(CRBFN) based adaptive equalizer for compensation of nonlinearities in digital satellite communication channels. The proposed CRBFN untilizes a complex-valued hybrid learning algorithm of k-means clustering and LMS(least mean sequare) algorithm that is an extension of Moody Darken's algorithm for real-valued data. We evaluate performance of CRBFN in terms of symbol error rates and mean squared errors nder various noise conditions for 4-PSK(phase shift keying) digital modulation schemes and compare with those of comples pth order inverse adaptive Volterra filter. The computer simulation results show that the proposed CRBFN ehibits good equalization, low computational complexity and fast learning capabilities.

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Construction Site Scene Understanding: A 2D Image Segmentation and Classification

  • Kim, Hongjo;Park, Sungjae;Ha, Sooji;Kim, Hyoungkwan
    • International conference on construction engineering and project management
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    • 2015.10a
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    • pp.333-335
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    • 2015
  • A computer vision-based scene recognition algorithm is proposed for monitoring construction sites. The system analyzes images acquired from a surveillance camera to separate regions and classify them as building, ground, and hole. Mean shift image segmentation algorithm is tested for separating meaningful regions of construction site images. The system would benefit current monitoring practices in that information extracted from images could embrace an environmental context.

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Real-Time Human Tracking Using Skin Area and Modified Multi-CAMShift Algorithm (피부색과 변형된 다중 CAMShift 알고리즘을 이용한 실시간 휴먼 트래킹)

  • Min, Jae-Hong;Kim, In-Gyu;Baek, Joong-Hwan
    • Journal of Advanced Navigation Technology
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    • v.15 no.6
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    • pp.1132-1137
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    • 2011
  • In this paper, we propose Modified Multi CAMShift Algorithm(Modified Multi Continuously Adaptive Mean Shift Algorithm) that extracts skin color area and tracks several human body parts for real-time human tracking system. Skin color area is extracted by filtering input image in predefined RGB value range. These areas are initial search windows of hands and face for tracking. Gaussian background model prevents search window expending because it restricts skin color area. Also when occluding between these areas, we give more weights in occlusion area and move mass center of target area in color probability distribution image. As result, the proposed algorithm performs better than the original CAMShift approach in multiple object tracking and even when occluding of objects with similar colors.

Measurement Based Visualization Method of Radio Wave Environment Using a Mode Seeking Algorithm (모드 탐색 알고리즘을 이용한 측정치 기반의 전파 환경 시각화 기법)

  • Na, Dong Yeop;Koo, Hyung Il;Park, Yong Bae;Lee, Kyoung Hoon;Lee, Jae Ki;Hwang, In Ho
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.25 no.3
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    • pp.296-303
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    • 2014
  • In this paper, we propose an algorithm to visualize radio wave environment based on the measured Received Signal Strength Indication( RSSI) and 3D geographic information. We estimate the source position using the circumcenter of the triangle and visualize the radio wave environment using the empirical propagation models. A mode seeking algorithm(mean-shift clustering) is used to seek the peak points and the center of gravity is utilized to reduce the estimation errors. Our approach finds its applications in the radio wave monitoring systems for the efficient utilization of radio resources.

Target-Tracking System for Mobile Surveillance Robot Using CAMShift Image Processing Technique (CAMShift 영상 처리 기법을 이용한 기동형 경계 로봇의 목표추적 시스템)

  • Seo, Bong-Cheol;Kim, Sung-Soo;Lee, Dong-Youm
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.38 no.2
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    • pp.129-136
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    • 2014
  • Target-tracking systems are important for carrying out effective surveillance missions using mobile surveillance robots. In this paper, we propose a target-tracking algorithm using camera image data for a three-axis mobile surveillance robot and carry out an actual hardware test for verifying the proposed algorithm. The heading direction vector of a camera system is deduced from the position error between the viewfinder center and the object center in a camera image. The position error is obtained using the CAMShift(Continuously Adaptive Mean Shift) algorithm, an image processing technique. The performance test of an actual three-axis mobile surveillance robot was carried out for verifying the proposed target-tracking algorithm in a real environment.

Design of Pedestrian Detection and Tracking System Using HOG-PCA and Object Tracking Algorithm (HOG-PCA와 객체 추적 알고리즘을 이용한 보행자 검출 및 추적 시스템 설계)

  • Jeon, Pil-Han;Park, Chan-Jun;Kim, Jin-Yul;Oh, Sung-Kwun
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.66 no.4
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    • pp.682-691
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    • 2017
  • In this paper, we propose the fusion design methodology of both pedestrian detection and object tracking system realized with the aid of HOG-PCA based RBFNN pattern classifier. The proposed system includes detection and tracking parts. In the detection part, HOG features are extracted from input images for pedestrian detection. Dimension reduction is also dealt with in order to improve detection performance as well as processing speed by using PCA which is known as a typical dimension reduction method. The reduced features can be used as the input of the FCM-based RBFNNs pattern classifier to carry out the pedestrian detection. FCM-based RBFNNs pattern classifier consists of condition, conclusion, and inference parts. FCM clustering algorithm is used as the activation function of hidden layer. In the conclusion part of network, polynomial functions such as constant, linear, quadratic and modified quadratic are regarded as connection weights and their coefficients of polynomial function are estimated by LSE-based learning. In the tracking part, object tracking algorithms such as mean shift(MS) and cam shift(CS) leads to trace one of the pedestrian candidates nominated in the detection part. Finally, INRIA person database is used in order to evaluate the performance of the pedestrian detection of the proposed system while MIT pedestrian video as well as indoor and outdoor videos obtained from IC&CI laboratory in Suwon University are exploited to evaluate the performance of tracking.