Effective Passive Multitarget Localization Using Maximum Likelihood

Localization of multiple targets is a challenging task due to immense complexity regarding data fusion received at the sensors. In this context, we propose an algorithm to solve the problem for an unknown number of emitters without prior knowledge to address the data fusion problem. The proposed technique combines the time difference of arrival (TDOA) and frequency difference of arrival (FDOA) measurement data fusion which further uses the maximum likelihood of the measurements received at each sensor of the surveillance region. The measurement grids of the sensors are used to perform data association. The simulation results show that the proposed algorithm outperforms the multipass grid search and further effectively eliminated the ghost targets created due to the fusion of measurements received at each sensor. Moreover, the proposed algorithm reduces the computational complexity compared to other existing algorithms as it does not use repeated steps for convergence or any biological evolutions. Furthermore, the experimental testing of the proposed technique was executed successfully for tracking multiple targets in different scenarios passively.

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Application of Multi-Source Data Fusion Method in Updating Topography and Estimating Sedimentation of the Reservoir

Water ◽

10.3390/w12113057 ◽

2020 ◽

Vol 12 (11) ◽

pp. 3057

Author(s):

Yu Liu ◽

Shiguo Xu ◽

Tongxin Zhu ◽

Tianxiang Wang

Keyword(s):

Data Fusion ◽

Northeast China ◽

Bottom Topography ◽

Measurement Data ◽

Average Error ◽

Source Data ◽

Sedimentation Volume ◽

Simulation Results ◽

The Difference ◽

Total Sedimentation

The underwater terrain of a reservoir can experience significant changes due to the effects of erosion and siltation during decades of operation. Therefore, existing topographic data no longer reflect current reservoir terrains and need to be updated. In this paper, we propose a fast and economical method for updating the topography of a reservoir. According to multi-source data fusion, we effectively integrated sonar sounding data, cartographic data, and manual measurement data to update and reconstruct the bottom topography of a reservoir in Northeast China. By comparing the updated topography with the measured elevation, the average error of the simulation results is only 0.56%, which shows that the updated topography can accurately reflect the actual topography of the reservoir. Furthermore, by using the surface volume tool in ArcGIS, we developed the original and updated the elevation and volume curves of the reservoir. Finally, the amount of silting and its distribution in the reservoir were obtained by calculating the difference between the original and updated elevation and volume curves. The results show that the total sedimentation volume in the researching reservoir is about 4.3 million m3, which is mainly concentrated in the areas with an elevation below 50 m and above 60 m.

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Filtering Performance of Digital Alternate Array on Target Tracking

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.644-650.4269 ◽

2014 ◽

Vol 644-650 ◽

pp. 4269-4272

Author(s):

Dong Kai Cao ◽

Jun Li ◽

Hong Ming Liu

Keyword(s):

Kalman Filter ◽

Measurement Error ◽

Data Fusion ◽

Target Tracking ◽

Measurement Data ◽

New Method ◽

Present Moment ◽

Simulation Results ◽

Novel Model ◽

Error Filtering

For target tracking of agile digital array, we propose a novel model called alternate array. The model means that total array is divided into vertical subarray at the present moment, and vertical subarray is transformed into horizontal subarray at the next moment, then the subarray comes to the first subarray divisions, and so on. Alternate array gives rise to differences of statistical characters of measurement error. Filtering performance is influenced by the feature of measurement data. In the paper, we come up with a new method based on Kalman filter (KF) to solve the difficulty. The new method merges pre-processing and data fusion thought together. Simulation results demonstrate the validity of the proposed algorithm.

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A Least Square Solution for Energy-Based Source Localization in Sensor Networks

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.605-607.1094 ◽

2012 ◽

Vol 605-607 ◽

pp. 1094-1098

Author(s):

Na Jiang ◽

Wen Bao Ai

Keyword(s):

Sensor Networks ◽

Computational Complexity ◽

Maximum Likelihood ◽

Source Localization ◽

Relaxation Method ◽

Least Square ◽

Initial Estimate ◽

Least Square Problem ◽

Simulation Results ◽

High Degree

In this paper, we consider the energy-based source localization in sensor networks. A least square solution to the maximum likelihood (ML) formulation of energy-based source localization is proposed. Since the ML-formulation is nonlinear and non-convex, we approximate it to a convex least square problem which can be solved directly. Simulation results show that with a rough initial estimate range of the acoustic source’s location, the proposed method can achieve a high degree of accuracy. Moreover, with thousands of times lower computational complexity than the semi-definite relaxation method, the proposed method can be effectively used in real time location systems (RTLS).

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Data Fusion for Electromagnetic and Electrical Resistive Tomography Based on Maximum Likelihood

International Journal of Geophysics ◽

10.1155/2011/617089 ◽

2011 ◽

Vol 2011 ◽

pp. 1-11 ◽

Cited By ~ 2

Author(s):

Sven Nordebo ◽

Mats Gustafsson ◽

Therese Sjöden ◽

Francesco Soldovieri

Keyword(s):

Maximum Likelihood ◽

Inverse Problems ◽

Data Fusion ◽

Fisher Information ◽

Measurement Data ◽

Problem Formulation ◽

Truncated Singular Value Decomposition ◽

Tunnel Detection ◽

Maximum Likelihood Criterion ◽

Value Decomposition

This paper presents a maximum likelihood based approach to data fusion for electromagnetic (EM) and electrical resistive (ER) tomography. The statistical maximum likelihood criterion is closely linked to the additive Fisher information measure, and it facilitates an appropriate weighting of the measurement data which can be useful with multiphysics inverse problems. The Fisher information is particularly useful for inverse problems which can be linearized similar to the Born approximation. In this paper, a proper scalar product is defined for the measurements and a truncated Singular Value Decomposition (SVD) based algorithm is devised which combines the measurement data of the two imaging modalities in a way that is optimal in the sense of maximum likelihood. As a multiphysics problem formulation with applications in geophysics, the problem of tunnel detection based on EM and ER tomography is studied in this paper. To illustrate the connection between the Green's functions, the gradients and the Fisher information, two simple and generic forward models are described in detail regarding two-dimensional EM and ER tomography, respectively.

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A DOA Estimation Algorithm in OFDM Radar-Communication System for Vehicular Application

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.926-930.1853 ◽

2014 ◽

Vol 926-930 ◽

pp. 1853-1856 ◽

Cited By ~ 1

Author(s):

Xiao You Yu ◽

Ming Qian Zhou

Keyword(s):

Computational Complexity ◽

Covariance Matrix ◽

Communication System ◽

Estimation Algorithm ◽

Doa Estimation ◽

Beam Forming ◽

Spatial Covariance ◽

Multiple Targets ◽

Simulation Results ◽

Eigen Decomposition

According to IEEE Std 802.11p, a fast DOA estimation algorithm of multiple targets based on beam-forming techniques in OFDM radar-communication system for vehicular applications is discussed in this paper. The proposed algorithm has reduced computational complexity utilizing high order power of the inverse spatial covariance matrix without eigen-decomposition. Simulation results demonstrate it is suitable for vehicular application.

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An Intelligent Evaluation Method to Analyze the Competitiveness of Airlines

Mathematical Problems in Engineering ◽

10.1155/2020/8589346 ◽

2020 ◽

Vol 2020 ◽

pp. 1-9

Author(s):

Jun Zhao ◽

Xumei Chen

Keyword(s):

Neural Network ◽

Prior Knowledge ◽

Evaluation Method ◽

Standard Sample ◽

Reference Value ◽

The Self ◽

Index Data ◽

Som Neural Network ◽

Simulation Results ◽

Self Organizing

An intelligent evaluation method is presented to analyze the competitiveness of airlines. From the perspective of safety, service, and normality, we establish the competitiveness indexes of traffic rights and the standard sample base. The self-organizing mapping (SOM) neural network is utilized to self-organize and self-learn the samples in the state of no supervision and prior knowledge. The training steps of high convergence speed and high clustering accuracy are determined based on the multistep setting. The typical airlines index data are utilized to verify the effect of the self-organizing mapping neural network on the airline competitiveness analysis. The simulation results show that the self-organizing mapping neural network can accurately and effectively classify and evaluate the competitiveness of airlines, and the results have important reference value for the allocation of traffic rights resources.

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Study on Optimization of the Number of DF Stations

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.709.485 ◽

2014 ◽

Vol 709 ◽

pp. 485-490

Author(s):

Xiang Wu ◽

Jun Jun Zong ◽

Xun Xue Cui ◽

Chuan Xu Liu

Keyword(s):

Maximum Likelihood ◽

Maximum Likelihood Estimation ◽

Likelihood Estimation ◽

Direction Finding ◽

Location Error ◽

Location Accuracy ◽

Error Models ◽

Reasonable Number ◽

Simulation Results

Reasonable number of direction finding station is examined in multi-station bearing-crossing location. Though it is believed that increasing the number of station is helpful to improve the location accuracy, In the paper, the maximum likelihood estimation (MLE) as an example. The algorithms and the location error models are given. The simulation results show that the location accuracy will be improved quickly with the increase of the number of the measuring participants, but the improvement will be sharply slowed down if too many station involved, which also boost the complexity of location.

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Modeling of German Low Voltage Cables with Ground Return Path

Energies ◽

10.3390/en14051265 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1265 ◽

Cited By ~ 1

Author(s):

Johanna Geis-Schroer ◽

Sebastian Hubschneider ◽

Lukas Held ◽

Frederik Gielnik ◽

Michael Armbruster ◽

...

Keyword(s):

Low Voltage ◽

Measurement Data ◽

Analytical Calculation ◽

Laboratory Measurement ◽

Model Parameters ◽

Calculation Methods ◽

Modeling Approach ◽

Measurement Results ◽

Simulation Results ◽

Return Path

In this contribution, measurement data of phase, neutral, and ground currents from real low voltage (LV) feeders in Germany is presented and analyzed. The data obtained is used to review and evaluate common modeling approaches for LV systems. An alternative modeling approach for detailed cable and ground modeling, which allows for the consideration of typical German LV earthing conditions and asymmetrical cable design, is proposed. Further, analytical calculation methods for model parameters are described and compared to laboratory measurement results of real LV cables. The models are then evaluated in terms of parameter sensitivity and parameter relevance, focusing on the influence of conventionally performed simplifications, such as neglecting house junction cables, shunt admittances, or temperature dependencies. By comparing measurement data from a real LV feeder to simulation results, the proposed modeling approach is validated.

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Analytical Investigation of Tension Loaded Deformed Rebar Anchors in Concrete

CivilEng ◽

10.3390/civileng2020025 ◽

2021 ◽

Vol 2 (2) ◽

pp. 442-458

Author(s):

Sandip Chhetri ◽

Rachel A. Chicchi

Keyword(s):

Test Data ◽

Parametric Study ◽

Failure Modes ◽

Experimental Testing ◽

Analytical Investigation ◽

Failure Behavior ◽

Capacity Design ◽

Simulation Results

Experimental testing of deformed rebar anchors (DRAs) has not been performed extensively, so there is limited test data to understand their failure behavior. This study aims to expand upon these limited tests and understand the behavior of these anchors, when loaded in tension. Analytical benchmark models were created using available test data and a parametric study of deformed rebar anchors was performed. Anchor diameter, spacing, embedment, and number of anchors were varied for a total of 49 concrete breakout simulations. The different failure modes of anchors were predicted analytically, which showed that concrete breakout failure is prominent in the DRA groups. The predicted concrete breakout values were consistent with mean and 5% fractile concrete capacities determined from the ACI concrete capacity design (CCD) method. The 5% fractile factor determined empirically from the simulation results was kc = 26. This value corresponds closely with kc = 24 specified in ACI 318-19 and ACI 349-13 for cast-in place anchors. The analysis results show that the ACI CCD formula can be conservatively used to design DRAs loaded in tension by applying a kc factor no greater than 26.

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