Test Bed Structure Research Articles

Comparative Study of Predictive Analysis Methods to Estimate Bridge Response

Monitoring bridge performance is crucial to ensure safety and allocate resources in a cost-effective manner. This paper aims to reduce the gap between researchers and practitioners by showing how predictive analytics can be employed in the process of distilling operational information out of bridge monitoring data. Furthermore, it has the goal to aid infrastructure owners and managers in evaluating bridge performance over time and making data-driven decisions to prolong the life of the structure. To achieve this goal, the paper presents a comparative study of three predictive analysis models to estimate bridge response to heavy trucks: multilinear regression, artificial neural network, and regression tree. Following this comparison, an alternative strategy, based on the analysis of influential observations, is proposed. This approach brings together predictive power with other important capabilities such as explanatory capabilities and interpretability. The test bed structure is a short-span highway bridge which was monitored for 3 years using weigh-in-motion (traffic data) and structural health monitoring (bridge data) systems.

Inline state of health estimation of lithium-ion batteries using state of charge calculation

The determination of state-of-health (SOH) and state-of-charge (SOC) is challenging and remains as an active research area in academia and industry due to its importance for Li-ion battery applications. The estimation process poses more challenges after substantial battery aging. This paper presents an inline SOH and SOC estimation method for Li-ion battery packs, specifically for those based on LiFePO4 chemistry. This new hybridized SOC and SOH estimator can be used for battery packs. Inline estimated model parameters were used in a compounded SOC + SOH estimator consisting of the SOC calculation based on coulomb counting method as an expedient approach and an SOH observer using an extended Kalman filter (EKF) technique for calibrating the estimates from the coulomb counting method. The algorithm's low SOC and SOH estimation error, fast response time, and less-demanding computational requirement make it practical for on-board estimations. The simulation and experimental results, along with the test bed structure, are presented to validate the proposed methodology on a single cell and a 3S1P LiFePO4 battery pack.

Test and Analysis of Friction Torque for Wind Turbine Pitch Bearing

In this paper, we introduce a new test method for friction performance of wind turbine pitch bearing. Four loading devices are used to put on load on the pitch bearing from different directions through load board. It can accurately simulate the axial force, radial force and overturning moment of wind turbine pitch bearing. The data acquisition device can measure the value of speed, torque and actual output load of loading hydraulic cylinder. After analysis and calculation, the influence of additional friction torque produced by loading device can be obviated, the friction torque of wind turbine pitch bearing under different loads can be test accurately in the laboratory. The research shows that the structure of test bed is compact, mechanical rigidity is good, the replacement of bearing model is expedient. It puts on load easily and can measure the frictional torque of wind turbine pitch bearing under different loads more accurately. It can provide data for performance analysis of wind turbine pitch bearing and ensure the pitch bearing satisfying the application requirements.

New Technologies Proven in Precast Concrete Modular Floating Pier for U.S. Navy

Representing a breakthrough in naval vessel berthing infrastructure, a test bed structure for a large-scale modular hybrid floating pier was designed with state-of-the-art precast/prestressed concrete technology and a number of material and design innovations. In 2004, the $5 million 15.2 x 30.5 x 8.8 m (50 x 100 x 29 ft) test structure was fabricated, erected, and open-ocean towed to its final destination in San Diego, California, as proof of concept for a future $45 million, 400 m (1300 ft) long double-deck floating pier for the U.S. Navy. The Modular Hybrid Pier was conceived as a replacement for obsolete and deteriorating naval berthing facilities. Designed for 100 years of repair-free service, the pier will provide a high level of support services to a variety of vessel classes and facilitate a rapid upgrade of vessel utilities with the advance of fleet support system technologies. More than 25 government, university, and private entities collaborated to develop this groundbreaking concept in precast concrete pier infrastructure.

3D Monte Carlo Analysis of Discrete Dopant Effects on Electron noise in Si Devices

This paper reports for the first time a simulation study of thermal noise in a simple test bed structure (three nanometric Si resistors) using an atomistic model and a continuum one. The 3D Monte Carlo atomistic approach that describes the electron-impurity interaction in the presence of discrete impurities was presented in (Barraud et al., 2002). This model has been successfully used to compute the electron mobility in Si resistors as a function of average doping concentration and to study the effect of impurity position in the channel of 50-nm MOSFET (Dolfus et al., 2004).