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MINIMUM SPANNING-TREES FOR TREE METRICS - ABRIDGMENTS AND ADJUSTMENTS

JOURNAL OF CLASSIFICATION 1995年第2期12卷 207-241页

作者： LECLERC, B ECOLE HAUTES ETUD SCI SOCIALES CTR ANAL & MATH SOCIALES54 BD RASPAILF-75270 PARIS 06FRANCE

Two properties of tree metrics are already known in the literature: tree metrics on a set X with n elements have 2n - 3 degrees of freedom;a tree metric has Robinson form with regard to its minimum spanning tree (MST), or to any such MST if several of them exist. Starting from these results, we prove that a tree metric t is entirely defined by its restriction to some set B of 2n - 3 entries. This set is easily determined from the table of t and includes the n - 1 entries of an MST A fast method for the adjustment of a tree metric to any given metric d is then obtained. This method extends to dissimilarities.

关键词： TREE METRIC ULTRAMETRIC ROBINSON DISSIMILARITY DISSIMILARITY GRAPH TREE MINIMUM SPANNING TREE fitting algorithm COMBINATORIAL DATA ANALYSIS

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IVIM MRI - Evolution from DWI, Observations, Challenges and Relevance of pre and post processing phases 5

IVIM MRI - Evolution from DWI, Observations, Challenges and ...

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5th International Conference on Electrical, Electronics, Communication, Computer Technologies and Optimization Techniques (ICEECCOT)

作者： Raju, Jini Amma, Ushadevi C. John, Ansamma APJ Abdul Kalam Technol Univ Thangal Kunju Musaliar Coll Engn Dept Comp Sci & Engn Kollam Kerala India Amrita Vishwa Vidhyapeetham Dept Elect & Commun Engn Amritapuri Campus Kollam Kerala India

ISBN: (纸本)9781665432726

Intravoxel Incoherent Motion Magnetic Resonance Imaging(IVIM MRI) is a quantitative, non invasive imaging technique that exploits perfusion and diffusion properties of tissues. Even though IVIM has grown in popularity in recent years, there is still a lot of research being done in the field, from image acquisition to disease diagnosis. This paper explores various challenges faced by researchers as well as clinicians during the IVIM image acquisition and postprocessing phases, through experimental analysis. The numerous issues associated with image acquisition phase are the properly fixing up of b value count, absolute b values, threshold b value and the highest achievable b value. The selection of image formats and correlation between slices in IVIM MRI images are other significant challenges during the image acquisition phase. The selection of appropriate fitting algorithm, for the estimation of IVIM parameters, is the major challenge in the post processing phase which is addressed by selecting an algorithm based on the quality off, D and D* maps generated. Since IVIM is in its infancy stage, the lack of real IVIM images is one of the major hurdles in IVIM research and hence simulated data is also used in addition to the available real dataset.

关键词： Diffusion Weighted Imaging Intravoxel Incoherent Motion Imaging fitting algorithm Image Postprocessing

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Line Measurement of Multi-Beam Sounding System Based on Annealing algorithm

Line Measurement of Multi-Beam Sounding System Based on Anne...

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2023 IEEE International Conference on Electrical, Automation and Computer Engineering, ICEACE 2023

作者： Yan, Xiaochen Lv, Lingfeng Xi, Rui Nanjing University of Aeronautics and Astronautics Nanjing China

ISBN: (纸本)9798350309614

For a group of parallel survey lines with sloping sea floor at a certain Angle to the horizontal plane, the total path of the route is different when the Angle projected by the normal direction of the slope changes. This paper studies the shortest path when the value of the Angle is taken. The possible interval of the shortest path is calculated by the set of all possible obtained Angle values through certain traversal calculation method, and then the trend of path change is analyzed by fitting calculation method, and the Angle value of the shortest path is analyzed by annealing algorithm. After several studies to eliminate errors, it is found that the path is shortest when the direction of the measured line is perpendicular to the normal projection. © 2023 IEEE.

关键词： angle set annealing algorithm fitting algorithm shortest path traversal algorithm

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Axial peak extraction in the measurement of subsurface structures with annular illumination confocal microscopy

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SURFACE TOPOGRAPHY-METROLOGY AND PROPERTIES 2024年第3期12卷 035030-035030页

作者： Jiang, Yong Liu, Chenguang Zou, Chongliang Liu, Jian Harbin Inst ofTechnol Adv Microscopy & Instrumentat Res Ctr Sch Instrumentat Sci & Engn Harbin 150001 Peoples R China

Three-dimensional dark-field confocal microscopy (DFCM) using annular illumination and complementary detection apertures is capable of detecting subsurface defects in ultra-precision optical components. In this study, a DFCM tuning algorithm for large apertures is proposed based on the sinc2 tuning model. This algorithm provides a reliable and theoretically accurate method for extracting the axial position during the measurement of subsurface defects. The rationality and accuracy of this method are verified through simulations and experimental results.

关键词： dark-field confocal microscopy axial peak extraction fitting algorithm

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Improvement and Performance Evaluation of a Dual-Probe Heat Pulse Distributed Temperature Sensing Method Used for Soil Moisture Estimation

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SENSORS 2022年第19期22卷 7592页

作者： Yao, Jun-Cheng Shi, Bin Liu, Jie Sun, Meng-Ya Fang, Ke Yao, Jian Gu, Kai Zhang, Wei Zhang, Ji-Wen Nanjing Univ Sch Earth Sci & Engn Nanjing 210023 Peoples R China Hohai Univ Sch Earth Sci & Engn Nanjing 210098 Peoples R China Jiangsu Prov Engn Invest & Res Inst Co Ltd Yangzhou 225002 Jiangsu Peoples R China China JK Inst Engn Invest & Design Co Ltd Xian 710043 Peoples R China

Large-scale measurements of soil moisture play a critical role in many fields, such as agriculture, hydrology, and engineering. The distributed temperature sensing (DTS) technology, based on a dual-probe heat pulse (DPHP), is a novel approach to realizing large-scale soil moisture estimation. However, the application of the method is limited by the complex optical cable layout, calculation algorithm, and lack of standardized heating strategy. In this paper, an improved DPHP-DTS method considering the soil bulk density was proposed. The measurement accuracy of the DPHP-DTS method under different heating strategies was studied in laboratory experiments, and its long-term stability in regard to the monitoring of soil moisture during natural evaporation in different soils was tested. The results show that the improved DPHP-DTS method can accurately measure the soil moisture, and the fitting algorithm can reduce the error caused by the accuracy of the DTS temperature measurement under the low-power heating strategy. Its measurement accuracy increases with the increase in the heating strength and duration. In addition, the improved DPHP-DTS method can describe soil evaporation in both sand and loess with good reliability and stability.

关键词： soil moisture estimation dual-probe heat pulse (DPHP) distributed temperature sensing (DTS) heating strategy fitting algorithm

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A Modular Control Scheme for Hyper-redundant Robots

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INTERNATIONAL JOURNAL OF ADVANCED ROBOTIC SYSTEMS 2015年第7期12卷 91-91页

作者： Cho, Chang Nho Jung, Hyunchul Son, Jaebum Kim, Kwang Gi Natl Canc Ctr Goyang Gyeonggi Do South Korea

Hyper-redundant robots, robots with many degrees of freedom, are considered to be advantageous in many tasks, such as minimally invasive surgery, surveillance and inspection. However, due to their hyper degrees of freedom, the control of hyper-redundant robots is always challenging. Several fitting algorithms, which iteratively fit a hyper-redundant robot into a continuous curve, have been proposed to control the configuration of hyper-redundant robots. However, these algorithms require heavy computation, preventing them from being used in practice. In this study, we propose a novel modular control scheme for a hyper-redundant robot to reduce the computational load by dividing the robot into smaller modules and fitting each module separately. A Jacobian-based position control algorithm is also used to utilize the redundancy of each module to ensure that the overall configuration of the robot resembles the given desired curve. Simulation results show that the proposed scheme can be used to control hyper-redundant robots effectively.

关键词： fitting algorithm Hyper-Redundant Robot Redundancy Resolution Weight Least Norm

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Development of a hybrid system for automatic identification of brushed direct current motors

Development of a hybrid system for automatic identification ...

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IEEE International Congress on Electronics, Electrical Engineering and Computing (INTERCON)

作者： Franz Hamann Gustavo Mesones Electronics engineering faculty Universidad Peruana de Ciencias Aplicadas Lima Perú

ISBN: (数字)9781728193779

ISBN: (纸本)9781728193786

This work proposes a low-cost hybrid hardware and software system that, through a set of methods and nested while loop fitting algorithms, allows to automatically identify the electrical and mechanical parameters of a brushed direct current motor. The aim is to facilitate a tool that contributes to the development of motion control projects in which this type of actuator is used, automating and speeding up the identification process of the motor system aiming to reach 98% accuracy, in order to guarantee a good electrical and mechanical parameter estimates for the brushed direct current motor. To achieve the objective, a platform was developed consisting of a main interface programmed in Matlab and a data acquisition hardware based on a single-phase incremental optical encoder, an H-bridge, an optocoupler circuit, and a C language-programmed DSPIC30F2010. Both parts of the platform are interconnected through the authors' own serial communication protocol.

关键词： Hybrid system fitting algorithm motion control brushed direct current motor identification automatic DC motor parameters DC motors hybrid systems Motor Control AUTOMATIC Automatic identification Brushed main interface Data Collection Methods mechanical parameter

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Shape Model fitting using Non-Isotropic GMM

Shape Model fitting using Non-Isotropic GMM

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IET Irish Signals and Systems Conference

作者： Claudia Arellano Rozenn Dahyot School of Computer Science and Statistics Trinity College Dublin

ISBN: (纸本)9781629935867

We present a Mean Shift algorithm for fitting shape models. This algorithm maximises a posterior density function where the likelihood is defined as the Euclidean distance between two Gaussian mixture density functions, one modelling the observations while the other corresponds to the shape model. We explore the role of the covariance matrix in the Gaussian kernel for encoding the shape of the model in the density function. Results show that using non-isotropic covariance matrices improve the efficiency of the algorithm and allow to reduce the number of kernels to use in the mixture without compromising the robustness of the algorithm.

关键词： Morphable Models fitting algorithm Gaussian Mixture Models Mean Shift

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Automated Macro Approach to Remove Vitelline Membrane Autofluorescence in

Automated Macro Approach to Remove Vitelline Membrane Autofl...

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作者： Jaume Boix-Fabrés Katerina Karkali Enrique Martín-Blanco Elena Rebollo

This chapter provides an ImageJ/Fiji automated macro approach to remove the vitelline membrane autofluorescence in live Drosophila embryo movies acquired in a 4D (3D plus time) fashion. The procedure consists in a segmentation pipeline that can cope with different relative intensities of the vitelline membrane autofluorescence, followed by a developed algorithm that adjusts the extracted outline selection to the shape deformations that naturally occur during Drosophila embryo development. Finally, the fitted selection is used to clear the external glowing halo that, otherwise, would obscure the visualization of the internal embryo labeling upon projection or 3D rendering. less

关键词： Live Cell Imaging ImageJ Fiji Drosophila Autofluorescence Vitelline membrane Membrane segmentation 3D projection fitting algorithm

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Ocean Wind Speed Retrieved from X-Band Radar Image

Ocean Wind Speed Retrieved from X-Band Radar Image

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2015 International Conference on Automation,Mechanical Control and Computational Engineering(AMCCE 2015)

作者： Meng Xu Xiao-liang Chu Jian Wang Ye-hui Wang Kai-jin Wei Tao Zhou College of Information and Engineering Ocean University of China First Institute of Oceanography State Oceanic Administration

ISBN: (纸本)9781510803084

A method for wind speed retrieval is developed by applying fitting techniques with the ratio of signal to noise. The method is applied to the wind speed retrieval from the nautical radar images. And we get a correlation coefficient of 0.88 and RMS error of 1.34m/s by comparing the data from the radar and in-situ data. The results show that this method can be used to estimate the wind speed.

关键词： X-band radar wind speed fitting algorithm

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