An Advanced Sensor for Particles in Gases Using Dynamic Light Scattering in Air as Solvent

Dynamic Light Scattering is a technique currently used to assess the particle size and size distribution by processing the scattered light intensity. Typically, the particles to be investigated are suspended in a liquid solvent. An analysis of the particular conditions required to perform a light scattering experiment on particles in air is presented in detail, together with a simple experimental setup and the data processing procedure. The results reveal that such an experiment is possible and using the setup and the procedure, both simplified to extreme, enables the design of an advanced sensor for particles and fumes that can output the average size of the particles in air.

3-D Data Processing to Extract Vehicle Trajectories from Roadside LiDAR Data

High-resolution vehicle data including location, speed, and direction is significant for new transportation systems, such as connected-vehicle applications, micro-level traffic performance evaluation, and adaptive traffic control. This research developed a data processing procedure for detection and tracking of multi-lane multi-vehicle trajectories with a roadside light detection and ranging (LiDAR) sensor. Different from existing methods for vehicle onboard sensing systems, this procedure was developed specifically to extract high-resolution vehicle trajectories from roadside LiDAR sensors. This procedure includes preprocessing of the raw data, statistical outlier removal, a Least Median of Squares based ground estimation method to accurately remove the ground points, vehicle data clouds clustering, a principle component-based oriented bounding box method to estimate the location of the vehicle, and a geometrically-based tracking algorithm. The developed procedure has been applied to a two-way-stop-sign intersection and an arterial road in Reno, Nevada. The data extraction procedure has been validated by comparing tracking results and speeds logged from a testing vehicle through the on-board diagnostics interface. This data processing procedure could be applied to extract high-resolution trajectories of connected and unconnected vehicles for connected-vehicle applications, and the data will be valuable to practices in traffic safety, traffic mobility, and fuel efficiency estimation.

Expanding Plug Wedge Test for Evaluating Hoop Tensile Properties of Fuel Cladding

An expanding plug wedge test method was developed to determine hoop tensile properties of irradiated fuel cladding in a hot cell [1]. Ring specimens with the plug-wedge insert were fabricated based Finite Element Analysis (FEA) design. After several design and modification iterations, the protocol was validated for M5 and Zr-4 cladding. Results show that tested ring specimens have uniform radial expansion deformation in the gage section. The test data processing procedure was developed based on the energy approach to generate hoop stress-strain correlation. α factor estimated from FEA was used to remove dissipated friction energy. With the proposed method, optimized specimen design, and data processing procedure, the protocol validates that the measured piston load, plug extension, and ring radial expansion can be effectively and accurately converted into the hoop stress-strain curve for clad tubing structural material characterization. Validation proved that the expanding plug wedge test method is robust and can be easily performed.

RECONSTRUCTION OF INDOOR MODELS USING POINT CLOUDS GENERATED FROM SINGLE-LENS REFLEX CAMERAS AND DEPTH IMAGES

This paper presents a data acquisition system consisting of multiple RGB-D sensors and digital single-lens reflex (DSLR) cameras. A systematic data processing procedure for integrating these two kinds of devices to generate three-dimensional point clouds of indoor environments is also developed and described. In the developed system, DSLR cameras are used to bridge the Kinects and provide a more accurate ray intersection condition, which takes advantage of the higher resolution and image quality of the DSLR cameras. Structure from Motion (SFM) reconstruction is used to link and merge multiple Kinect point clouds and dense point clouds (from DSLR color images) to generate initial integrated point clouds. Then, bundle adjustment is used to resolve the exterior orientation (EO) of all images. Those exterior orientations are used as the initial values to combine these point clouds at each frame into the same coordinate system using Helmert (seven-parameter) transformation. Experimental results demonstrate that the design of the data acquisition system and the data processing procedure can generate dense and fully colored point clouds of indoor environments successfully even in featureless areas. The accuracy of the generated point clouds were evaluated by comparing the widths and heights of identified objects as well as coordinates of pre-set independent check points against in situ measurements. Based on the generated point clouds, complete and accurate three-dimensional models of indoor environments can be constructed effectively.

Quantitative Method for Assessing the Level of Deterioration of round Wood Guardrail Posts

This paper presents results of a study that developed a procedure for measuring the amount of deterioration damage of round wood guardrail posts. The guardrail posts used in the study were extracted from damaged guardrail installations in Ohio. A resistograph device was used to measure the resistance of a [Formula: see text] in. drilling needle passing through the cross section of the guardrail posts. The deterioration damage levels of the posts ranged from severe to essentially undamaged. A data processing procedure was developed to convert the resistograph data into a quantitative damage score. Physical impact tests were then performed to correlate the damage score to the dynamic strength properties of the posts.