Recent bcoe_research items

bonjourl

Thu, 27 Jun 2024 00:00:00 +0000

bonjourl

Spark Plasma Sintering of Non-Thermal Plasma Synthesized Silicon Carbonitride Nanoparticles

Tue, 28 May 2024 00:00:00 +0000

Spark Plasma Sintering of Non-Thermal Plasma Synthesized Silicon Carbonitride Nanoparticles

Supplementary Materials: RAIM and Failure Mode Slope: Effects of Increased Number of Measurements and Number of Faults.

Fri, 19 May 2023 00:00:00 +0000

Supplementary Materials: RAIM and Failure Mode Slope: Effects of Increased Number of Measurements and Number of Faults.

Using PPP Information to Implement a Global Real-Time Virtual Network DGNSS Approach

Tue, 28 Jun 2022 00:00:00 +0000

Differential Global Navigation Systems (DGNSS) has been demonstrated to provide reliable, high-quality range correction information enabling real-time navigation with centimeter to sub-meter accuracy, which is required for applications such as connected and autonomous vehicles. However, DGNSS requires a local reference station near each user. For a continental or global scale implementation, this information dissemination approach would require a dense network of reference stations whose construction and maintenance would be prohibitively expensive. Precise Point Positioning (PPP) affords more flexibility as a public service for GNSS receivers, but its State Space Representation (SSR) format is not supported by most receivers in the field or on the market.

This article proposes a novel Virtual Network (VN)DGNSS approach and an optimization algorithm that is key to its implementation. The approach capitalizes on the existing PPP infrastructure without the need for new...

Sparse Tracking State Estimation for Low-Observable Power Distribution Systems Using D-PMUs

Wed, 1 Jun 2022 00:00:00 +0000

Sparse Tracking State Estimation for Low-Observable Power Distribution Systems Using D-PMUs

A Synchronized Lissajous-based Method to Detect and Classify Events in Synchro-waveform Measurements in Power Distribution Networks

Wed, 1 Jun 2022 00:00:00 +0000

A Synchronized Lissajous-based Method to Detect and Classify Events in Synchro-waveform Measurements in Power Distribution Networks

Synchronous Waveform Measurements to Locate Transient Events and Incipient Faults in Power Distribution Networks

Wed, 1 Jun 2022 00:00:00 +0000

Synchronous Waveform Measurements to Locate Transient Events and Incipient Faults in Power Distribution Networks

Earth Centered Earth Fixed INS Equations

Thu, 12 May 2022 00:00:00 +0000

Earth Centered Earth Fixed INS Equations

Quaternion-based Trajectory Tracking Control of VTOL-UAVs using Command Filtered Backstepping

Wed, 14 Jul 2021 00:00:00 +0000

This document is reference [14] cited in the paper:

S. Zhao, W. Dong, and J. A. Farrell, "Quaternion-based Trajectory Tracking Control of VTOL-UAVs using Command Filtered Backstepping," American Control Conference, pp. 1018-1023, June 2013. DOI: 10.1109/ACC.2013.6579970.

This technical report contains more details than the conference paper. Please cite the ACC paper rather than this technical report.

IMU Error Modeling Tutorial: INS state estimation with real-time sensor calibration

Thu, 20 May 2021 00:00:00 +0000

This article is a tutorial describing the process and issues related to developing a state-space model for the stochastic errors affecting an Inertial Measurement Unit (IMU). The starting point is the instrument error characterization data sheet provided by the manufacturer, which is typically either an Allan Variance graph or the parameters extracted from that graph. Along with this tutorial, supplementary software is available for open source distribution that calculates and plots the Allan Variance for a given set of data; extracts optimal parameters (e.g., $Q_N$, $Q_B$, $Q_K$, and $T_B$) from Allan Variance data for a given model structure; and, computes and simulates of the discrete-time equivalent model.

On a Security vs Privacy Trade-off in Interconnected Dynamical Systems

Sat, 12 Dec 2020 00:00:00 +0000

On a Security vs Privacy Trade-off in Interconnected Dynamical Systems

Technical Note: Derivation of Earth-Rotation Correction (Sagnac)and Analysis of the Effect of Receiver Clock Bias

Tue, 28 Jan 2020 00:00:00 +0000

Technical Note: Derivation of Earth-Rotation Correction (Sagnac)and Analysis of the Effect of Receiver Clock Bias

Technical Note: CRT with Least Soft-thresholded Squares

Tue, 17 Sep 2019 00:00:00 +0000

Technical Note: CRT with Least Soft-thresholded Squares

ECEF Position Accuracy and Reliability:Continent Scale Differential GNSS Approaches (Phase C Report)

Tue, 17 Sep 2019 00:00:00 +0000

ECEF Position Accuracy and Reliability:Continent Scale Differential GNSS Approaches (Phase C Report)

Technical note with Supporting Results forOutlier Accommodation Nonlinear State Estimation:A Risk-Averse Performance-Specified Approach

Tue, 25 Jun 2019 00:00:00 +0000

This tech note extends the discussion of the numericalresults in [1]. The main article should be read first. Thatarticle presents RAPS for nonlinear applications; therefore,linear systems are a special case. This technical note includesnumerical results specific to linear systems that did not fitwithin the journal page constraints. Section I briefly introduceslinear system mode model. Section III studies the performanceof the binary RAPS approach for vehicle state estimation. Thelinear application is referred to in the GNSS literature as a PVAmodel wherein the GNSS measurements are used to estimatethe position, velocity, and acceleration of the GNSS antenna.Such estimators are included in almost all GNSS receivers.

ECEF Position Accuracy and Reliabilityin the Presence of Differential Correction LatencyPhase B Technical Reportfor Sirius XM

Wed, 19 Jun 2019 00:00:00 +0000

Many applications, including connected and autonomous vehicles, would benefit from navigation technologies reliablyachieving sub-meter position accuracy with high reliability on moving platforms. Commercial on-vehicle implementation ofEarth-referenced positioning at submeter accuracy with 99% probability would require widely and reliably available differentialcorrections; however, such corrections delivered on a nationwide or global scale via satellite systems will incur latency betweentheir time-of-applicability and their time-of-reception at the vehicle.Phase 1 of this project presented a differential correction computation methodology designed to be robust to latency andstudied position accuracy as a function of differential correction latency for stationary receivers [1]–[3]. The study showed thatsubmeter accuracy at 95% probability was achievable when a sufficient number and diversity of satellites were available.This report summarizes the conclusions of the Phase 2 of the...

Technical note with Supporting Results for Outlier Accommodation State Estimation:A Risk-Averse Performance-Specified Approach

Wed, 31 Oct 2018 00:00:00 +0000

This tech note extends the discussion of the numerical results in [1]. The main article should be read first. This technical note includes numerical results that could not fitwithin the journal page constraints. It presents the statistics of the vertical error for the nonlinear (INS) model and discussesthe interplay between the error, risk, and GDOP metrics for portions of an experiment using the linear (PVA) model. The error, risk and PVA metrics are defined in Sections VIII-C and VIII-E of [1].Each table and figure herein considers five algorithms, as summarized in Section VIII-B of [1]. Four of the algorithms are the NP-(E)KF with four different values of the decision parameter g. The final algorithm is the RAPS approach.

ECEF Position Accuracy and Reliabilityin the Presence of Differential Correction Latency Year 1 Technical Report for Sirius XM

Mon, 29 Oct 2018 00:00:00 +0000

Commercial on-vehicle implementation of Earth-referenced positioning at submeter accuracy with 99% probability wouldrequire widely and reliably available differential corrections; however, such corrections delivered on a nationwide or global scale via satellite systems will incur latency between their time-of-applicability and their time-of-reception at the vehicle.This report summarizes the conclusions of the first phase of work performed by University of California, Riverside (UCR).There were two main goals for this one-year effort.1) To investigate the sensitivity of differential Global Navigation Satellite System (DGNSS) corrections and positionestimation accuracy to communication latency.2) To investigate the feasibility of achieving meter-level positioning accuracy at least 95% of epochs.The first phase of this project was designed to study stationary receivers, to clearly define, demonstrate, and address thechallenging issues. In this study, all algorithms use identical...

Technical Note: INS Noise Propagation

Mon, 29 Oct 2018 00:00:00 +0000

This Technical Note is supplied to explain the state and noise propagation for an inertial navigation system (INS), betweentwo aiding measurement times. The temporal propagation of the state error and noise is required for optimal state estimation.

Technical Note: CRT with Hypothesis Testing

Tue, 28 Feb 2017 00:00:00 +0000

Technical Note: CRT with Hypothesis Testing

Best Practices for Surveying and Mapping Roadways and Intersections for Connected Vehicle Applications

Mon, 6 Jun 2016 00:00:00 +0000

Best Practices for Surveying and Mapping Roadways and Intersections for Connected Vehicle Applications

Network Consistent Data Association

Fri, 1 Aug 2014 00:00:00 +0000

Existing data association techniques mostly focus on sequentially matching pairs of data-point sets and then repeating this process along space-time to achieve long term correspondences. However, in many problems such as person re-identification, a set of data-points may be observed at multiple spatio-temporal locations and/or by multiple agents in a network and simply combining the local pairwise association results between sets of data-points often lead to inconsistencies over the global space-time horizons. In this paper, we propose a novel Network Consistent Data Association (NCDA) framework formulated as an optimization problem that not only maintains consistency in association results across the network, but also improves the pairwise data association accuracies. The proposed NCDA can be solved as a binary integer program leading to a globally optimal solution and is capable of handling the challenging data-association scenario where the number of data-points varies across...

A Conditional Random Field Model For Tracking In Densely Packed Cell Structures - A Technical Report

Fri, 14 Feb 2014 00:00:00 +0000

A Conditional Random Field Model For Tracking In Densely Packed Cell Structures - A Technical Report

Real Time Detection and Recognition of License Plate in Bengali

Mon, 25 Nov 2013 00:00:00 +0000

Real Time Detection and Recognition of License Plate in Bengali

Integrating Geometric, Motion and Appearance Constraints for Robust Tracking in Aerial Videos

Wed, 4 Sep 2013 00:00:00 +0000

The analysis of videos from aerial platforms remains a challenging and important problem. The most fundamental task in this regard is to be able to detect and track objects reliably from a moving platform. In this paper, we address the problem of multi-target detection and tracking in unconstrained aerial videos. Generally, aerial videos are very unstable due to air turbulence and targets of interest have few discriminating features, which impose strong challenges in tracking objects such as humans and vehicles. In our proposed approach, we stabilize an unstable aerial video using homography transformation. We estimate the homography between two frames of an unstable video by utilizing the geometric constraint of the ground plane. In order to detect targets in a stabilized video frame, we detect motion regions and then identify targets of interest around the motion regions using appearance based pre-trained classifiers. We devise a finite state machine (FSM) that incorporates...

2D LIDAR Aided INS for Vehicle Positioning in Urban Environments

Mon, 1 Jul 2013 00:00:00 +0000

This paper presents a novel method to utilize\textit{2D} LIDAR for INS (Inertial Navigation System) aiding to improve\textit{3D} vehicle position estimation accuracy, especially when GNSS signals are shadowed.In the proposed framework, 2D LIDAR aiding is carried out without imposing any assumptions on the vehicle motion (e.g. we allow full six degree-of freedom motion).To achieve this, a closed-form formula is derived to predict the line measurement in the LIDAR's frame.This makes the feature association, residual formation and GUI display possible.With this formula, the Extended Kalman Filter (EKF) can be employed in a straightforward manner to fuse the LIDAR and IMU data to estimate the full state of the vehicle.

Preliminary experimental results show the effectiveness of the LIDAR aiding in reducing the state estimation uncertainty along certain directions, when GNSS signals are shadowed.

Adaptive Geometric Tessellation For 3D Reconstruction of Anisotropically Developing Cells In Multilayer Tissues From Sparse Volumetric Microscopy Images

Wed, 8 May 2013 00:00:00 +0000

The need for quantification of cell growth patterns in a multilayer, multi-cellular tissue necessitates the development of a 3D reconstruction technique that can estimate 3D shapes and sizes of individual cells from Confocal Microscopy (CLSM) image slices. However, the current methods of 3D reconstruction using CLSM imaging require large number of image slices per cell. But, in case of Live Cell Imaging of an actively developing tissue, large depth resolution is not feasible in order to avoid damage to cells from prolonged exposure to laser radiation. In the present work, we have proposed an anisotropic Voronoi tessellation based 3D reconstruction framework for a tightly packed multilayer tissue with extreme z-sparsity (2-4 slices/cell) and wide range of cell shapes and sizes. The proposed method, named as the `Adaptive Quadratic Voronoi Tessellation' (AQVT), is capable of handling both the sparsity problem and the non-uniformity in cell shapes by estimating the tessellation parameters...

Reliability-constrained area optimization of VLSI power/ground networks via sequence of linear programmings

Wed, 17 Apr 2013 00:00:00 +0000

Reliability-constrained area optimization of VLSI power/ground networks via sequence of linear programmings

Cooperative, Opportunistic Imaging within a Bayesian Distributed Constrained Optimization Framework

Fri, 14 Sep 2012 00:00:00 +0000

Cooperative, Opportunistic Imaging within a Bayesian Distributed Constrained Optimization Framework