Non-Destructive Testing of Structures Using Optical and Other Methods: A Review

Non-destructive testing (NDT) of structures is one of the most important tasks of the proper maintenance and diagnosis of machines and constructions structural condition. NDT methods contribute to the damage tolerance philosophy used in the aircraft design methodology as well as many other operation and maintenance programs of machinery and constructions. The following study is focusing on overviewing an important group of NDT methods: the optical and other ones, which found broad applicability in scientific and industrial studies nowadays. The paper discusses the selected most widely applicable methods, namely, visual testing, ultrasonic testing, radiographic testing, infrared thermography as well as electronic speckle pattern interferometry and shearographic testing. Besides the basic principles of testing using these methods, their potential applications in various industrial and technological branches are broadly discussed. The analysis as categorization of the NDT methods provided in this paper may help in selection of such methods in diagnosis of various types of structures and defects and damage occurring in these structures

A Combine On-Line Acoustic Flowmeter and Fluorocarbon Coolant Mixture Analyzer for The ATLAS Silicon Tracker

An upgrade to the ATLAS silicon tracker cooling control system may require a change from C3F8 (octafluoro-propane) to a blend containing 10-30% of C2F6 (hexafluoro-ethane) to reduce the evaporation temperature and better protect the silicon from cumulative radiation damage with increasing LHC luminosity. Central to this upgrade is a new acoustic instrument for the real-time measurement of the C3F8/C2F6 mixture ratio and flow. The instrument and its Supervisory, Control and Data Acquisition (SCADA) software are described in this paper. The instrument has demonstrated a resolution of 3.10-3 for C3F8/C2F6 mixtures with ~20%C2F6, and flow resolution of 2% of full scale for mass flows up to 30gs-1. In mixtures of widely-differing molecular weight (mw), higher mixture precision is possible: a sensitivity of < 5.10-4 to leaks of C3F8 into the ATLAS pixel detector nitrogen envelope (mw difference 160) has been seen. The instrument has many potential applications, including the analysis of mixtures of hydrocarbons, vapours for semi-conductor manufacture and anaesthesia

Development of a custom on-line ultrasonic vapour analyzer/flowmeter for the ATLAS inner detector, with application to gaseous tracking and Cherenkov detectors

Precision sound velocity measurements can simultaneously determine binary gas composition and flow. We have developed an analyzer with custom electronics, currently in use in the ATLAS inner detector, with numerous potential applications. The instrument has demonstrated ~0.3% mixture precision for C3F8/C2F6 mixtures and < 10-4 resolution for N2/C3F8 mixtures. Moderate and high flow versions of the instrument have demonstrated flow resolutions of +/- 2% F.S. for flows up to 250 l.min-1, and +/- 1.9% F.S. for linear flow velocities up to 15 ms-1; the latter flow approaching that expected in the vapour return of the thermosiphon fluorocarbon coolant recirculator being built for the ATLAS silicon tracker.Comment: Paper submitted to TWEPP2012; Topical Workshop on Electronics for Particle Physics, Oxford, UK, September 17-21, 2012. KEYWORDS: Sonar; Saturated fluorocarbons; Flowmetry; Sound velocity, Gas mixture analysis. 8 pages, 7 figure

Conformational changes of the small ribosomal subunit during elongation factor G-dependent tRNA–mRNA translocation.

Translocation, a coordinated movement of two tRNAs together with mRNA on the ribosome, is catalyzed by elongation factor G (EF-G). The reaction is accompanied by conformational rearrangements of the ribosome that are, as yet, not well characterized. Here, we analyze those rearrangements by restricting the conformational flexibility of the ribosome by antibiotics binding to specific sites of the ribosome. Paromomycin (Par), viomycin (Vio), spectinomycin (Spc), and hygromycin B (HygB) inhibited the tRNA-mRNA movement, while the other partial reactions of translocation, including the unlocking rearrangement of the ribosome that precedes tRNA-mRNA movement, were not affected. The functional cycle of EF-G, i.e. binding of EF-G(.)GTP to the ribosome, GTP hydrolysis, Pi release, and dissociation of EF-G(.)GDP from the ribosome, was not affected either, indicating that EF-G turnover is not coupled directly to tRNA-mRNA movement. The inhibition of translocation. by Par and Vio is attributed to the stabilization of tRNA binding in the A site, whereas Spc and HygB had a direct inhibitory effect on tRNA-mRNA movement. Streptomycin (Str) had essentially no effect on translocation, although it caused a large increase in tRNA affinity to the A site. These results suggest that conformational changes in the vicinity of the decoding region at the binding sites of Spc and HygB are important for tRNA-mRNA movement, whereas Str seems to stabilize a conformation of the ribosome that is prone to rapid translocation, thereby compensating the effect on tRNA affinity. (C) 2004 Elsevier Ltd. All rights reserved

An elongation factor G-induced ribosome rearrangement precedes tRNA-mRNA translocation.

The elongation cycle of protein synthesis is completed by translocation, a rearrangement during which two tRNAs; bound to the mRNA move on the ribosome. The reaction is promoted by elongation factor G (EF-G) and accelerated by GTP hydrolysis. Here we report a pre-steady-state kinetic analysis of translocation. The kinetic model suggests that GTP hydrolysis drives a conformational rearrangement of the ribosome that precedes and limits the rates of tRNA-mRNA translocation and Pi release from EF-G.GDP.Pi. The latter two steps are intrinsically rapid and take place at random. These results indicate that the energy of GTP hydrolysis is utilized to promote the ribosome rearrangement and to bias spontaneous fluctuations within the ribosome-EF-G complex toward unidirectional movement of mRNA and tRNA

An open-source framework for automated high-throughput cell biology experiments

Modern data analysis methods, such as optimization algorithms or deep learning have been successfully applied to a number of biotechnological and medical questions. For these methods to be efficient, a large number of high-quality and reproducible experiments needs to be conducted, requiring a high degree of automation. Here, we present an open-source hardware and low-cost framework that allows for automatic high-throughput generation of large amounts of cell biology data. Our design consists of an epifluorescent microscope with automated XY stage for moving a multiwell plate containing cells and a perfusion manifold allowing programmed application of up to eight different solutions. Our system is very flexible and can be adapted easily for individual experimental needs. To demonstrate the utility of the system, we have used it to perform high-throughput Ca2+ imaging and large-scale fluorescent labeling experiments

Development of sustainable transport in smart cities

© 2017 IEEE. Smart Mobility is one of the main directions of transportation systems development in Smart Cities. In this case along with intellectualization of management the issue of transition to 'green', safe and sustainable modes of transport, such as bicycle, should be solved. Democracy and availability, cheapness and environmental friendliness, promotion of healthy lifestyle are the reasons for the growing popularity of this mode of transport all over the world. This paper proposes one of the possible ways of bicycle transport development in smart city, that allows expanding the number of users by reducing physical requirements for cyclist. The proposed development represents a concept of the Smart Bike that monitors condition of the cyclist and environment and turns on electric motor in critical situations. This reduces physical load of cyclist, as well as the battery consumption, that positively affects the ecology of Smart Cities

Translation Lookaside Buffer on the 65-nm STG DICE Hardened Elements

This paper presents the design of hardened translation lookaside buffer based on Spaced Transistor Groups (STG) DICE cells in 65-nm bulk CMOS technology. The resistance to impacts of single nuclear particles is achieved by spacing transistors in two groups together with transistors of the output combinational logic. The elements contain two spaced identical groups of transistors. Charge collection from particle tracks by only transistors of just one of the two groups doesn’t lead to the cell upset. The proposed logical element of matching based on the STG DICE cell for a content-addressable memory was simulated using TCAD tool. The results show the resistance to impacts of single nuclear particles with linear energy transfer (LET) values up to 70 MeV×cm2/mg. Short-term noise pulses in combinational logic of the element can be observed in the range of LET values from 20 to 70 MeV×cm2/mg