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Improving Video Watermarking through Galois Field GF(2^(4)) Multiplication Tables with Diverse Irreducible Polynomials and Adaptive Techniques
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作者 Yasmin Alaa Hassan Abdul Monem S.Rahma 《Computers, Materials & Continua》 SCIE EI 2024年第1期1423-1442,共20页
Video watermarking plays a crucial role in protecting intellectual property rights and ensuring content authenticity.This study delves into the integration of Galois Field(GF)multiplication tables,especially GF(2^(4))... Video watermarking plays a crucial role in protecting intellectual property rights and ensuring content authenticity.This study delves into the integration of Galois Field(GF)multiplication tables,especially GF(2^(4)),and their interaction with distinct irreducible polynomials.The primary aim is to enhance watermarking techniques for achieving imperceptibility,robustness,and efficient execution time.The research employs scene selection and adaptive thresholding techniques to streamline the watermarking process.Scene selection is used strategically to embed watermarks in the most vital frames of the video,while adaptive thresholding methods ensure that the watermarking process adheres to imperceptibility criteria,maintaining the video's visual quality.Concurrently,careful consideration is given to execution time,crucial in real-world scenarios,to balance efficiency and efficacy.The Peak Signal-to-Noise Ratio(PSNR)serves as a pivotal metric to gauge the watermark's imperceptibility and video quality.The study explores various irreducible polynomials,navigating the trade-offs between computational efficiency and watermark imperceptibility.In parallel,the study pays careful attention to the execution time,a paramount consideration in real-world scenarios,to strike a balance between efficiency and efficacy.This comprehensive analysis provides valuable insights into the interplay of GF multiplication tables,diverse irreducible polynomials,scene selection,adaptive thresholding,imperceptibility,and execution time.The evaluation of the proposed algorithm's robustness was conducted using PSNR and NC metrics,and it was subjected to assessment under the impact of five distinct attack scenarios.These findings contribute to the development of watermarking strategies that balance imperceptibility,robustness,and processing efficiency,enhancing the field's practicality and effectiveness. 展开更多
关键词 Video watermarking galois field irreducible polynomial multiplication table scene selection adaptive thresholding
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TRANSLATION-INVARIANT BASED ADAPTIVE THRESHOLD DENOISING FOR IMPACT SIGNAL 被引量:4
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作者 GaiGuanghong QuLiangsheng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2004年第4期552-555,共4页
A translation-invariant based adaptive threshold denoising method formechanical impact signal is proposed. Compared with traditional wavelet denoising methods, itsuppresses pseudo-Gibbs phenomena in the neighborhood o... A translation-invariant based adaptive threshold denoising method formechanical impact signal is proposed. Compared with traditional wavelet denoising methods, itsuppresses pseudo-Gibbs phenomena in the neighborhood of signal discontinuities. To remedy thedrawbacks of conventional threshold functions, a new improved threshold function is introduced. Itpossesses more advantages than others. Moreover, based on utilizing characteristics of signal, aadaptive threshold selection procedure for impact signal is proposed. It is data-driven andlevel-dependent, therefore, it is more rational than other threshold estimation methods. Theproposed method is compared to alternative existing methods, and its superiority is revealed bysimulation and real data examples. 展开更多
关键词 Translation-invariant adaptive threshold Impact signal DENOISING Wavelettransform
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An automatic detection of green tide using multi-windows with their adaptive threshold from Landsat TM/ETM plus image 被引量:4
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作者 WANG Changying CHU Jialan +3 位作者 TAN Meng SHAO Fengjing SUI Yi LI Shujing 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第11期106-114,共9页
Since the atmospheric correction is a necessary preprocessing step of remote sensing image before detecting green tide, the introduced error directly affects the detection precision. Therefore, the detection method of... Since the atmospheric correction is a necessary preprocessing step of remote sensing image before detecting green tide, the introduced error directly affects the detection precision. Therefore, the detection method of green tide is presented from Landsat TM/ETM plus image which needs not the atmospheric correction. In order to achieve an automatic detection of green tide, a linear relationship(y =0.723 x+0.504) between detection threshold y and subtraction x(x=λnir–λred) is found from the comparing Landsat TM/ETM plus image with the field surveys.Using this relationship, green tide patches can be detected automatically from Landsat TM/ETM plus image.Considering there is brightness difference between different regions in an image, the image will be divided into a plurality of windows(sub-images) with a same size firstly, and then each window will be detected using an adaptive detection threshold determined according to the discovered linear relationship. It is found that big errors will appear in some windows, such as those covered by clouds seriously. To solve this problem, the moving step k of windows is proposed to be less than the window width n. Using this mechanism, most pixels will be detected[n/k]×[n/k] times except the boundary pixels, then every pixel will be assigned the final class(green tide or sea water) according to majority rule voting strategy. It can be seen from the experiments, the proposed detection method using multi-windows and their adaptive thresholds can detect green tide from Landsat TM/ETM plus image automatically. Meanwhile, it avoids the reliance on the accurate atmospheric correction. 展开更多
关键词 automatic detection green tide adaptive threshold Landsat TM/ETM plus image
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Self-adaptive large neighborhood search algorithm for parallel machine scheduling problems 被引量:7
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作者 Pei Wang Gerhard Reinelt Yuejin Tan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第2期208-215,共8页
A self-adaptive large neighborhood search method for scheduling n jobs on m non-identical parallel machines with mul- tiple time windows is presented. The problems' another feature lies in oversubscription, namely no... A self-adaptive large neighborhood search method for scheduling n jobs on m non-identical parallel machines with mul- tiple time windows is presented. The problems' another feature lies in oversubscription, namely not all jobs can be scheduled within specified scheduling horizons due to the limited machine capacity. The objective is thus to maximize the overall profits of processed jobs while respecting machine constraints. A first-in- first-out heuristic is applied to find an initial solution, and then a large neighborhood search procedure is employed to relax and re- optimize cumbersome solutions. A machine learning mechanism is also introduced to converge on the most efficient neighborhoods for the problem. Extensive computational results are presented based on data from an application involving the daily observation scheduling of a fleet of earth observing satellites. The method rapidly solves most problem instances to optimal or near optimal and shows a robust performance in sensitive analysis. 展开更多
关键词 non-identical parallel machine scheduling problem with multiple time windows (NPMSPMTW) oversubscribed self- adaptive large neighborhood search (SALNS) machine learning.
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Reconstruction method of irregular seismic data with adaptive thresholds based on different sparse transform bases 被引量:2
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作者 Zhao Hu Yang Tun +4 位作者 Ni Yu-Dong Liu Xing-Gang Xu Yin-Po Zhang Yi-Lei Zhang Guang-Rong 《Applied Geophysics》 SCIE CSCD 2021年第3期345-360,432,共17页
Oil and gas seismic exploration have to adopt irregular seismic acquisition due to the increasingly complex exploration conditions to adapt to complex geological conditions and environments.However,the irregular seism... Oil and gas seismic exploration have to adopt irregular seismic acquisition due to the increasingly complex exploration conditions to adapt to complex geological conditions and environments.However,the irregular seismic acquisition is accompanied by the lack of acquisition data,which requires high-precision regularization.The sparse signal feature in the transform domain in compressed sensing theory is used in this paper to recover the missing signal,involving sparse transform base optimization and threshold modeling.First,this paper analyzes and compares the effects of six sparse transformation bases on the reconstruction accuracy and efficiency of irregular seismic data and establishes the quantitative relationship between sparse transformation and reconstruction accuracy and efficiency.Second,an adaptive threshold modeling method based on sparse coefficient is provided to improve the reconstruction accuracy.Test results show that the method has good adaptability to different seismic data and sparse transform bases.The f-x domain reconstruction method of effective frequency samples is studied to address the problem of low computational efficiency.The parallel computing strategy of curvelet transform combined with OpenMP is further proposed,which substantially improves the computational efficiency under the premise of ensuring the reconstruction accuracy.Finally,the actual acquisition data are used to verify the proposed method.The results indicate that the proposed method strategy can solve the regularization problem of irregular seismic data in production and improve the imaging quality of the target layer economically and efficiently. 展开更多
关键词 irregular acquisition seismic data reconstruction adaptive threshold f-x domain OpenMP parallel optimization sparse transformation
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Adaptive median threshold algorithm used in FDIS of DSSS receivers 被引量:1
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作者 Weijun Yang Chaojie Zhang +2 位作者 Xiaojun Jin Zhonghe Jin Tieshan Yuan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第1期11-18,共8页
For direct sequence spread spectrum (DSSS) receivers, the capability of rejecting narrow-band interference can be significantly improved by a process of frequency-domain interference suppression (FDIS). The key is... For direct sequence spread spectrum (DSSS) receivers, the capability of rejecting narrow-band interference can be significantly improved by a process of frequency-domain interference suppression (FDIS). The key issue of this process is how to determine a threshold to eliminate interference in the frequency domain, which has been extensively studied. However, these previous methods are tedious or very complex. A simple and ef- ficient algorithm based on medians is proposed. The elimination threshold is only related to the median by a scale factor, which can be obtained by the numerical analysis. Simulation results show that the algorithm provides excellent narrow-band interfer- ence suppression while only slightly degrading the signal-to-noise ratio (SNR). A one-pass algorithm using logarithmic segmentation is further derived to estimate medians with low computational complexity. Finally, the FDIS is implemented in a field programmable gate array (FPGA) of Xilinx. Experiments are carried out by connecting the FDIS FPGA to a DSSS receiver, and the results show that the receiver has an effective countermeasure for a 60 dB interference-to-signal ratio (ISR). 展开更多
关键词 direct sequence spread spectrum (DSSS) discreteFourier transform (DFT) frequency-domain interference suppres-sion (FDIS) adaptive median threshold one-pass approximatemedians.
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Edge Detection of COVID-19 CT Image Based on GF_SSR, Improved Multiscale Morphology, and Adaptive Threshold 被引量:1
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作者 Shouming Hou Chaolan Jia +3 位作者 Kai Li Liya Fan Jincheng Guo Mackenzie Brown 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第7期81-94,共14页
Edge detection is an effective method for image segmentation and feature extraction.Therefore,extracting weak edges with the inhomogeneous gray of Corona Virus Disease 2019(COVID-19)CT images is extremely important.Mu... Edge detection is an effective method for image segmentation and feature extraction.Therefore,extracting weak edges with the inhomogeneous gray of Corona Virus Disease 2019(COVID-19)CT images is extremely important.Multiscale morphology has been widely used in the edge detection of medical images due to its excellent boundary detection accuracy.In this paper,we propose a weak edge detection method based on Gaussian filtering and singlescale Retinex(GF_SSR),and improved multiscale morphology and adaptive threshold binarization(IMSM_ATB).As all the CT images have noise,we propose to remove image noise by Gaussian filtering.The edge of CT images is enhanced using the SSR algorithm.In addition,based on the extracted edge of CT images using improved Multiscale morphology,a particle swarm optimization(PSO)algorithm is introduced to binarize the image by automatically getting the optimal threshold.To evaluate our method,we use images from three datasets,namely COVID-19,Kaggle-COVID-19,and COVID-Chestxray,respectively.The average values of results are worthy of reference,with the Shannon information entropy of 1.8539,the Precision of 0.9992,the Recall of 0.8224,the F-Score of 1.9158,running time of 11.3000.Finally,three types of lesion images in the COVID-19 dataset are selected to evaluate the visual effects of the proposed algorithm.Compared with the other four algorithms,the proposed algorithm effectively detects the weak edge of the lesion and provides help for image segmentation and feature extraction. 展开更多
关键词 COVID-19 SSR multiscale morphology PSO adaptive threshold edge detection
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Research on Adaptive Threshold of Received Signal in Communication System 被引量:3
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作者 Xizheng Ke Xukuan Ji 《Optics and Photonics Journal》 2021年第1期1-11,共11页
When the light beam propagates in the atmosphere, the signal will be absorbed and scattered by the gas molecules and water mist in the atmosphere, which will cause the loss of power rate. The complex atmospheric envir... When the light beam propagates in the atmosphere, the signal will be absorbed and scattered by the gas molecules and water mist in the atmosphere, which will cause the loss of power rate. The complex atmospheric environment will produce a variety of adverse effects on the signal. The interference produced by these effects overlaps with each other, which will seriously affect the strength of the received signal. Therefore, how to effectively suppress the atmospheric turbulence effect in the random atmospheric turbulence channel, ensure the normal transmission of the signal in the atmospheric channel, and reduce the bit error rate of the communication system, is very necessary to improve the communication system. When processing the received signal, it is an important step to detect the transmitted signal by comparing the received signal with the threshold. In this paper, based on the atmospheric turbulence distribution model, the adaptive signal decision threshold is obtained through the estimation of high-order cumulant. Monte Carlo method is used to verify the performance of adaptive threshold detection. The simulation results show that the high-order cumulant estimation of atmospheric turbulence parameters can realize the adaptive change of the decision threshold with the channel condition. It is shown that the adaptive threshold detection can effectively restrain atmospheric turbulence, improve the performance of free space optical and improve the communication quality. 展开更多
关键词 Free Space Optical adaptive threshold Detection Higller-Order Cumulants
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Defocus Blur Segmentation Using Local Binary Patterns with Adaptive Threshold 被引量:1
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作者 Usman Ali Muhammad Tariq Mahmood 《Computers, Materials & Continua》 SCIE EI 2022年第4期1597-1611,共15页
Enormousmethods have been proposed for the detection and segmentation of blur and non-blur regions of the images.Due to the limited available information about blur type,scenario and the level of blurriness,detection ... Enormousmethods have been proposed for the detection and segmentation of blur and non-blur regions of the images.Due to the limited available information about blur type,scenario and the level of blurriness,detection and segmentation is a challenging task.Hence,the performance of the blur measure operator is an essential factor and needs improvement to attain perfection.In this paper,we propose an effective blur measure based on local binary pattern(LBP)with adaptive threshold for blur detection.The sharpness metric developed based on LBP used a fixed threshold irrespective of the type and level of blur,that may not be suitable for images with variations in imaging conditions,blur amount and type.Contrarily,the proposed measure uses an adaptive threshold for each input image based on the image and blur properties to generate improved sharpness metric.The adaptive threshold is computed based on the model learned through support vector machine(SVM).The performance of the proposed method is evaluated using two different datasets and is compared with five state-of-the-art methods.Comparative analysis reveals that the proposed method performs significantly better qualitatively and quantitatively against all of the compared methods. 展开更多
关键词 adaptive threshold blur measure defocus blur segmentation local binary pattern support vector machine
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Adaptive Threshold Estimation of Open Set Voiceprint Recognition Based on OTSU and Deep Learning 被引量:1
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作者 Xudong Li Xinjia Yang Linhua Zhou 《Journal of Applied Mathematics and Physics》 2020年第11期2671-2682,共12页
Aiming at the problem of open set voiceprint recognition, this paper proposes an adaptive threshold algorithm based on OTSU and deep learning. The bottleneck technology of open set voiceprint recognition lies in the c... Aiming at the problem of open set voiceprint recognition, this paper proposes an adaptive threshold algorithm based on OTSU and deep learning. The bottleneck technology of open set voiceprint recognition lies in the calculation of similarity values and thresholds of speakers inside and outside the set. This paper combines deep learning and machine learning methods, and uses a Deep Belief Network stacked with three layers of Restricted Boltzmann Machines to extract deep voice features from basic acoustic features. And by training the Gaussian Mixture Model, this paper calculates the similarity value of the feature, and further determines the threshold of the similarity value of the feature through OTSU. After experimental testing, the algorithm in this paper has a false rejection rate of 3.00% for specific speakers, a false acceptance rate of 0.35% for internal speakers, and a false acceptance rate of 0 for external speakers. This improves the accuracy of traditional methods in open set voiceprint recognition. This proves that the method is feasible and good recognition effect. 展开更多
关键词 Voiceprint Recognition Deep Neural Network (DNN) OTSU adaptive threshold
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Discrete-Rate Adaptive Modulation with Variable Threshold for Distributed Antenna System in the Presence of Imperfect CSI 被引量:3
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作者 YU Xiangbin TAN Wenting +1 位作者 WU Binbin LI Yang 《China Communications》 SCIE CSCD 2014年第A01期31-39,共9页
关键词 分布式天线系统 自适应调制 CSI 不完全 可变 速率 离散 平均误码率
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Adaptive Threshold Median Filter for Multiple-Impulse Noise 被引量:4
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作者 姜波 黄炜 《Journal of Electronic Science and Technology of China》 2007年第1期70-74,共5页
Attenuating the noises plays an essential role in the image processing. Almost all the traditional median filters concern the removal of impulse noise having a single layer, whose noise gray level value is constant. I... Attenuating the noises plays an essential role in the image processing. Almost all the traditional median filters concern the removal of impulse noise having a single layer, whose noise gray level value is constant. In this paper, a new adaptive median filter is proposed to handle those images corrupted not only by single layer noise. The adaptive threshold median filter (ATMF) has been developed by combining the adaptive median filter (AMF) and two dynamic thresholds. Because of the dynamic threshold being used, the ATMF is able to balance the removal of the multiple-impulse noise and the quality of image. Comparison of the proposed method with traditional median filters is provided. Some visual examples are given to demonstrate the performance of the proposed filter. 展开更多
关键词 median filter adaptive median filter (AMF) adaptive threshold median filter(ATMF) multiple-impulse noise image processing
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Super-resolution reconstruction of synthetic-aperture radar image using adaptive-threshold singular value decomposition technique 被引量:2
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作者 朱正为 周建江 《Journal of Central South University》 SCIE EI CAS 2011年第3期809-815,共7页
A super-resolution reconstruction approach of radar image using an adaptive-threshold singular value decomposition (SVD) technique was presented,and its performance was analyzed,compared and assessed detailedly.First,... A super-resolution reconstruction approach of radar image using an adaptive-threshold singular value decomposition (SVD) technique was presented,and its performance was analyzed,compared and assessed detailedly.First,radar imaging model and super-resolution reconstruction mechanism were outlined.Then,the adaptive-threshold SVD super-resolution algorithm,and its two key aspects,namely the determination method of point spread function (PSF) matrix T and the selection scheme of singular value threshold,were presented.Finally,the super-resolution algorithm was demonstrated successfully using the measured synthetic-aperture radar (SAR) images,and a Monte Carlo assessment was carried out to evaluate the performance of the algorithm by using the input/output signal-to-noise ratio (SNR).Five versions of SVD algorithms,namely 1) using all singular values,2) using the top 80% singular values,3) using the top 50% singular values,4) using the top 20% singular values and 5) using singular values s such that s2≥max(s2)/rinSNR were tested.The experimental results indicate that when the singular value threshold is set as smax/(rinSNR)1/2,the super-resolution algorithm provides a good compromise between too much noise and too much bias and has good reconstruction results. 展开更多
关键词 合成孔径雷达图像 奇异值分解分析 超分辨率算法 自适应阈值 分解技术 SVD算法 评估算法 点扩散函数
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Autonomous Lane Keeping Solution Based on Adaptive Gray Threshold and Region of Interest
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作者 陈泽友 李文生 《自动化博览》 2011年第S2期127-131,共5页
Autonomous lane keeping is an important technology in intelligent transportation,which is used to avoid unnecessary traffic accidents caused by lane departure.To adapt different lighting environment,and make up ordina... Autonomous lane keeping is an important technology in intelligent transportation,which is used to avoid unnecessary traffic accidents caused by lane departure.To adapt different lighting environment,and make up ordinary Hough transform’s shortcomings of tardiness and poor immunity,we propose an improved algorithm by using adaptive gray threshold and setting Region of interest(ROI),to do the quick Hough transform for tracking lane line,implementing autonomous lane keeping. The dynamic adaptive threshold method can be suitable with different lighting conditions and quickly,accurately remove most of the information not relative to lane line.Meanwhile setting ROI can let the program only care about the specific region which can provide useful information and further reduce the processing data.And then on the basic of identification,we put forward some efficient innovation strategy about the control logic of straight state,curve state and the transition state.The experiment proves that this solution greatly raises efficiency. 展开更多
关键词 adaptIVE GRAY threshold Region of Interest(ROI) control logic MONOCULAR vision
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AN IMPLEMENTATION METHOD OF ADAPTIVE THRESHOLD TO DETECT MOVING TARGETS BASED ON ATI TECHNOLOGY 被引量:1
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作者 Zeng Bin Zhang Xiaoling Huang Shunji 《Journal of Electronics(China)》 2007年第6期787-791,共5页
AT-InSAR(Along Track Interferometric SAR) is a technique to detect slow-moving targets. However, the detection performance is greatly influenced by noise and clutter. In this paper, the influence of noise and clutter ... AT-InSAR(Along Track Interferometric SAR) is a technique to detect slow-moving targets. However, the detection performance is greatly influenced by noise and clutter. In this paper, the influence of noise and clutter on the detecting performance is analyzed. By simulating different background clutter and noise, the performances of the phase threshold and dual-threshold methods are discussed in detail, and then the adaptive-threshold method is proposed which can greatly improve the detection performance. 展开更多
关键词 雷达技术 通信技术 设计方案 侦测雷达
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AN IMPROVED ADAPTIVE THRESHOLD MODULATION METHOD FOR JITTER REDUCTION IN SDH/SONET
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作者 Shi Fuqiang Lin Xiaokang Feng Chongxi (Communication Div., Electron. Eng. Dept., Tsinghua University, Beijing 100084) 《Journal of Electronics(China)》 1999年第3期251-256,共6页
Adaptive threshold modulation is widely adopted in SDH/SONET network for pointer processing and mapping. When the processing rate is very high, the performance of an all digital implementation is limited by the phase ... Adaptive threshold modulation is widely adopted in SDH/SONET network for pointer processing and mapping. When the processing rate is very high, the performance of an all digital implementation is limited by the phase error resolution. Phase error re-sampling technique is adopted here for the all digital implementation of an improved adaptive threshold modulation, which can work in greatly reduced operating speed with high jitter and wander performance. The improved method is adopted in AU-4 and TU-12 pointer processors and the simulated performance is given. 展开更多
关键词 POINTER adjustment adaptive threshold MODULATION JITTER WANDER
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QRS waves detection algorithm based on positive-negative adaptive threshold method
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作者 尚宇 雷莎莎 《Journal of Beijing Institute of Technology》 EI CAS 2014年第1期63-66,共4页
In order to accurately detect the occasional negative R waves in electrocardiography (ECG) signals, the positive-negative adaptive threshold method is adopted to determine the positive R waves and the negative R wav... In order to accurately detect the occasional negative R waves in electrocardiography (ECG) signals, the positive-negative adaptive threshold method is adopted to determine the positive R waves and the negative R waves, according to difference characteristics of ECG signals. The Q and S waves can then be accurately positioned based on the basic characteristics of QRS waves. Finally, the algorithm simulation is made based on the signals from MIT-BIH database with MATLAB. The ex- perimental results show that the algorithm can improve the detection accuracy rate to 99. 91% and o- vercome the problem of larger computation load for wavelet transform and other methods, so the al- gorithm is suitable for real-time detection. 展开更多
关键词 QRS wave detection adaptive threshold diference electrocardiography(ECG) signals
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A Secure-Efficient Data Collection Algorithm Based on Self-Adaptive Sensing Model in Mobile Internet of Vehicles 被引量:1
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作者 LIANG Wei RUAN Zhiqiang +1 位作者 TANG Mingdong LI Peng 《China Communications》 SCIE CSCD 2016年第2期121-129,共9页
Existing research on data collection using wireless mobile vehicle network emphasizes the reliable delivery of information.However,other performance requirements such as life cycle of nodes,stability and security are ... Existing research on data collection using wireless mobile vehicle network emphasizes the reliable delivery of information.However,other performance requirements such as life cycle of nodes,stability and security are not set as primary design objectives.This makes data collection ability of vehicular nodes in real application environment inferior.By considering the features of nodes in wireless IoV,such as large scales of deployment,volatility and low time delay,an efficient data collection algorithm is proposed for mobile vehicle network environment.An adaptive sensing model is designed to establish vehicular data collection protocol.The protocol adopts group management in model communication.The vehicular sensing node in group can adjust network sensing chain according to sensing distance threshold with surrounding nodes.It will dynamically choose a combination of network sensing chains on basis of remaining energy and location characteristics of surrounding nodes.In addition,secure data collection between sensing nodes is undertaken as well.The simulation and experiments show that the vehicular node can realize secure and real-time data collection.Moreover,the proposed algorithm is superior in vehicular network life cycle,power consumption and reliability of data collection by comparing to other algorithms. 展开更多
关键词 数据采集算法 感知模型 移动车辆 安全性 自适应 传感器节点 网络环境 数据采集能力
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A Restricted, Adaptive Threshold Segmentation Approach for Processing High-Speed Image Sequences of the Glottis
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作者 Mathew Blanco Xin Chen Yuling Yan 《Engineering(科研)》 2013年第10期357-362,共6页
In this paper, we propose a restricted, adaptive threshold approach for the segmentation of images of the glottis acquired from high speed video-endoscopy (HSV). The approach involves first, identifying a region of in... In this paper, we propose a restricted, adaptive threshold approach for the segmentation of images of the glottis acquired from high speed video-endoscopy (HSV). The approach involves first, identifying a region of interest (ROI) that encloses the vocal-fold motion extent for each image frame as estimated by the different image sequences. This procedure is then followed by threshold segmentation restricted within the identified ROI for each image frame of the original image sequences, or referred to as sub-image sequences. The threshold value is adapted for each sub-image frame and determined by respective minimum gray-scale value that typically corresponds to a spatial location within the glottis. The proposed approach is practical and highly efficient for segmenting a vast amount of image frames since simple threshold method is adapted. Results obtained from the segmentation of representative clinical image sequences are presented to verify the proposed method. 展开更多
关键词 Segmentation GLOTTIS VOCAL FOLD Motion DIFFERENCE Image adaptive threshold
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Implementation of Adaptive Wavelet Thresholding Denoising Algorithm Based on DSP
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作者 张雪峰 康春霞 +1 位作者 裴峰 张志杰 《Journal of Measurement Science and Instrumentation》 CAS 2011年第3期272-275,共4页
By utilizing the capability of high-speed computing,powerful real-time processing of TMS320F2812 DSP,wavelet thresholding denoising algorithm is realized based on Digital Signal Processors.Based on the multi-resolutio... By utilizing the capability of high-speed computing,powerful real-time processing of TMS320F2812 DSP,wavelet thresholding denoising algorithm is realized based on Digital Signal Processors.Based on the multi-resolution analysis of wavelet transformation,this paper proposes a new thresholding function,to some extent,to overcome the shortcomings of discontinuity in hard-thresholding function and bias in soft-thresholding function.The threshold value can be abtained adaptively according to the characteristics of wavelet coefficients of each layer by adopting adaptive threshold algorithm and then the noise is removed.The simulation results show that the improved thresholding function and the adaptive threshold algorithm have a good effect on denoising and meet the criteria of smoothness and similarity between the original signal and denoising signal. 展开更多
关键词 自适应阈值 去噪算法 小波阈值 DSP TMS320F2812 数字信号处理器 阈值函数 多分辨率分析
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