State of the art in testing components

The use of components in development of complex software systems can surely have various benefits. Their testing, however, is still one of the open issues in software engineering. Both the developer of a component and the developer of a system using components often face the problem that information vital for certain development tasks is not available. Such a lack of information has various consequences to both. One of the important consequences is that it might not only obligate the developer of a system to test the components used, it might also complicate these tests. This article gives an overview of component testing approaches that explicitly respect a lack of information in development

AVstack: An Open-Source, Reconfigurable Platform for Autonomous Vehicle Development

Pioneers of autonomous vehicles (AVs) promised to revolutionize the driving experience and driving safety. However, milestones in AVs have materialized slower than forecast. Two culprits are (1) the lack of verifiability of proposed state-of-the-art AV components, and (2) stagnation of pursuing next-level evaluations, e.g., vehicle-to-infrastructure (V2I) and multi-agent collaboration. In part, progress has been hampered by: the large volume of software in AVs, the multiple disparate conventions, the difficulty of testing across datasets and simulators, and the inflexibility of state-of-the-art AV components. To address these challenges, we present AVstack, an open-source, reconfigurable software platform for AV design, implementation, test, and analysis. AVstack solves the validation problem by enabling first-of-a-kind trade studies on datasets and physics-based simulators. AVstack solves the stagnation problem as a reconfigurable AV platform built on dozens of open-source AV components in a high-level programming language. We demonstrate the power of AVstack through longitudinal testing across multiple benchmark datasets and V2I-collaboration case studies that explore trade-offs of designing multi-sensor, multi-agent algorithms

Separator development and testing of nickel-hydrogen cells

The components, design, and operating characteristics of Ni-H2 cells batteries were improved. A separator development program was designed to develop a separator that is resistant to penetration by oxygen and loose active material from then nickel electrode, while retraining the required chemical and thermal stability, reservoir capability, and high ionic conductivity. The performance of the separators in terms of cell operating voltage was to at least match that of state-of-the-art separators while eliminating the separator problems. The separators were submitted to initial screening tests and those which successfully completed the tests were built into Ni-H2 cells for short term testing. The separators with the best performance are tested for long term performance and life

NDE of Thick and Highly Reinforced Concrete Structures: State of the Art

AbstractThe objective of the report is to present the state-of-the art of non-destructive testing methods and technologies for the inspection of thick, heavily-reinforced structures, (e.g. found in nuclear power plants). Wall thicknesses can be in excess of one meter and the structures often have increased steel reinforcement density. The accessibility for any testing method may be limited due to the presence of liners and other components such as cast-in-place items. Testing methods have to provide solutions for tasks such as locating failure (inclusions, corrosion, voids, delaminations) in the structures or the assessment of the condition of the structure in general

Rotary telemetry system for temperature measurements in aircraft component testing

Aviation testing is intrinsically connected with rotary telemetry, which enables engineers to measure and verify parameters of high-speed aircraft engines components during laboratory testing. The main purpose of this article is to propose new design concept of smart telemetry module for temperature measurements, which could be easily adapted to various demands of high-speed rotary components tests and is more handful, functional and affordable than other solutions on the market. The result of the work is a telemetry system in form of light weight, PCB-based, wireless powered, smart transducer. Article presents state of art analysis, design and manufacturing steps, test results and conclusions

The Design and Performance of Cyber-Physical Middleware for Real-Time Hybrid Structural Testing

Real-time hybrid testing of civil structures, in which computational models and physical components must be integrated with high fidelity at run-time represents a grand challenge in the emerging area of cyber-physical systems. Actuator dynamics, complex interactions among computers and physical components, and computation and communication delays all must be managed carefully to achieve accurate tests. To address these challenges, we have developed a novel middleware for integrating cyber and physical components flexibly and with suitable timing behavior within a Cyber-physical Instrument for Real-time hybrid Structural Testing (CIRST). This paper makes three main contributions to the state of the art in middleware for cyber-physical systems: (1) a novel middleware architecture within which cyber-physical components can be integrated flexibly through XML-based configuration specifications, (2) an efficient middleware implementation in C++ that can maintain necessary real-time performance, and (3) a case study that evaluates the middleware\u27s performance and demonstrates its suitability for real-time hybrid testing

Compositional optimization of hard-magnetic phases with machine-learning models

Machine Learning (ML) plays an increasingly important role in the discovery and design of new materials. In this paper, we demonstrate the potential of ML for materials research using hard-magnetic phases as an illustrative case. We build kernel-based ML models to predict optimal chemical compositions for new permanent magnets, which are key components in many green-energy technologies. The magnetic-property data used for training and testing the ML models are obtained from a combinatorial high-throughput screening based on density-functional theory calculations. Our straightforward choice of describing the different configurations enables the subsequent use of the ML models for compositional optimization and thereby the prediction of promising substitutes of state-of-the-art magnetic materials like Nd$_2$Fe$_{14}$B with similar intrinsic hard-magnetic properties but a lower amount of critical rare-earth elements.Comment: 12 pages, 6 figure

Thermal-structural test facilities at NASA Dryden

The National Aero-Space Plane (NASP) has renewed interest in hypersonic flight and hot-structures technology development for both the airframe and engine. The NASA Dryden Thermostructures Research Facility is a unique national facility that was designed to conduct thermal-mechanical tests on aircraft and aircraft components by simulating the flight thermal environment in the laboratory. The layout of the facility is presented, which includes descriptions of the high-bay test area, the instrumentation laboratories, the mechanical loading systems, and the state-of-the-art closed-loop thermal control system. The hot-structures test capability of the facility is emphasized by the Mach-3 thermal simulation conducted on the YF-12 airplane. The Liquid-Hydrogen Structural Test Facility, which is presently in the design phase, will provide the capability of thermally testing structures containing hydrogen