Comprehensive Study of the Performance of Winter Tires on Ice, Snow, and Asphalt Roads: The Influence of Tire Type and Wear

2017 ◽  
Vol 45 (3) ◽  
pp. 175-199 ◽  
Author(s):  
Mattias Hjort ◽  
Olle Eriksson ◽  
Fredrik Bruzelius
Keyword(s):  
Vehicle Performance ◽  
Testing Facility ◽  
Recorded Data ◽  
Winter Road ◽  
Tire Testing ◽  
Tire Forces ◽  
Real Traffic ◽  
Real Vehicle ◽  
Comprehensive Study

ABSTRACT This work presents a comprehensive study of the performance of winter tires on snow, ice, and asphalt. A set of 77 different winter tires were carefully selected for the study. Of these, 27 were new and 50 were worn from real traffic use. All three tire types for winter conditions (Nordic, European, and studded) were represented. All tires have been tested using a mobile tire-testing device for snow and asphalt and using a stationary tire-testing facility for ice. Both devices recorded the tire forces and motions, enabling a close to complete stationary characterization of the tires. In addition, 42 of the tires were tested on a passenger car, where brake performance was evaluated for the three different road conditions. This enables a comparative study of performance between tire types and wear for various winter road conditions. The results suggest that the recorded data represent real vehicle performance. Some conclusions from the measurements are that the effect of wear is consistent between the tire groups and that the performance degradation is most noticeable on studded tires on ice and on European tires on snow.

Comprehensive Study on Thermal Aging and Ball Shear Characterization of SAC-X Solders

2021 ◽  
Author(s):  
Norhanani Binte Jaafar ◽  
Chong Ser Choong ◽  
Sharon Lim Pei Siang ◽  
Chai Tai Chong
Keyword(s):  
Thermal Aging ◽  
Ball Shear ◽  
Comprehensive Study

scholarly journals A comprehensive study on the fabrication and characterization of Ti–48Al–2Cr–2Nb preforms manufactured using electron beam melting

Materialia ◽  
2019 ◽  
Vol 6 ◽  
pp. 100284 ◽  
Author(s):  
Ercan Cakmak ◽  
Peeyush Nandwana ◽  
Dongwon Shin ◽  
Yukinori Yamamoto ◽  
Maxim N. Gussev ◽  
...  
Keyword(s):  
Electron Beam ◽  
Electron Beam Melting ◽  
Fabrication And Characterization ◽  
Comprehensive Study

scholarly journals A Geometrical Study on the Roof Tile-Shaped Modes in AlN-Based Piezoelectric Microcantilevers as Viscosity–Density Sensors

Sensors ◽  
2019 ◽  
Vol 19 (3) ◽  
pp. 658 ◽  
Author(s):  
Víctor Ruiz-Díez ◽  
Javier Toledo ◽  
Jorge Hernando-García ◽  
Abdallah Ababneh ◽  
Helmut Seidel ◽  
...  
Keyword(s):  
Resonant Frequency ◽  
Quality Factor ◽  
Q Factor ◽  
Liquid Media ◽  
Roof Tile ◽  
Aln Film ◽  
Monitoring Applications ◽  
Media Monitoring ◽  
Comprehensive Study

Cantilever resonators based on the roof tile-shaped modes have recently demonstrated their suitability for liquid media monitoring applications. The early studies have shown that certain combinations of dimensions and order of the mode can maximize the Q-factor, what might suggest a competition between two mechanisms of losses with different geometrical dependence. To provide more insight, a comprehensive study of the Q-factor and the resonant frequency of these modes in microcantilever resonators with lengths and widths between 250 and 3000 µm and thicknesses between 10 and 60 µm is presented. These modes can be efficiently excited by a thin piezoelectric AlN film and a properly designed top electrode layout. The electrical and optical characterization of the resonators are performed in liquid media and then their performance is evaluated in terms of quality factor and resonant frequency. A quality factor as high as 140 was measured in isopropanol for a 1000 × 900 × 10 µm3 cantilever oscillating in the 11th order roof tile-shaped mode at 4 MHz; density and viscosity resolutions of 10−6 g/mL and 10−4 mPa·s, respectively are estimated for a geometrically optimized cantilever resonating below 1 MHz.

scholarly journals The allosteric activation mechanism of a phospholipase A2-like toxin from Bothrops jararacussu venom: a dynamic description

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Antoniel A. S. Gomes ◽  
Fabio F. Cardoso ◽  
Maximilia F. Souza ◽  
Cristiano L. P. Oliveira ◽  
David Perahia ◽  
...  
Keyword(s):  
Conformational Changes ◽  
Activation Mechanism ◽  
Activation Process ◽  
Structural Determinants ◽  
Allosteric Activation ◽  
Bothrops Jararacussu ◽  
Inactive State ◽  
Dynamic Description ◽  
Comprehensive Study

Abstract The activation process of phospholipase A2-like (PLA2-like) toxins is a key step in their molecular mechanism, which involves oligomeric changes leading to the exposure of specific sites. Few studies have focused on the characterization of allosteric activators and the features that distinguish them from inhibitors. Herein, a comprehensive study with the BthTX-I toxin from Bothrops jararacussu venom bound or unbound to α-tocopherol (αT) was carried out. The oligomerization state of BthTX-I bound or unbound to αT in solution was studied and indicated that the toxin is predominantly monomeric but tends to oligomerize when complexed with αT. In silico molecular simulations showed the toxin presents higher conformational changes in the absence of αT, which suggests that it is important to stabilize the structure of the toxin. The transition between the two states (active/inactive) was also studied, showing that only the unbound BthTX-I system could migrate to the inactive state. In contrast, the presence of αT induces the toxin to leave the inactive state, guiding it towards the active state, with more regions exposed to the solvent, particularly its active site. Finally, the structural determinants necessary for a molecule to be an inhibitor or activator were analyzed in light of the obtained results.

Development of Hydrogen Loading System and Characterization of Tritiated Metallic Films for Betavoltaic Batteries

2014 ◽  
Author(s):  
Thomas E. Adams ◽  
Shripad T. Revankar
Keyword(s):  
Precise Measurement ◽  
Extreme Temperature ◽  
Hydrogen Gas ◽  
Metallic Films ◽  
Testing Facility ◽  
Beta Source ◽  
Loading System ◽  
Betavoltaic Cell ◽  
Extended Power

Betavoltaic cells can provide extended power up to 10 or more years in extreme temperature environments, −55°C to 150°C. However there is limited study on the loading of tritium which is beta source for these cells. The present study examines the loading of the tritium using surrogate hydrogen gas in various films through experiments and simulations. A detailed review of the betavoltaic cell characteristics is first discussed and key challenges in this technology are identified. For the experimental work, a testing facility is designed for loading hydrogen in metallic films such as titanium, palladium and scandium which are good for storage of hydrogen or tritium. The facility is unique as it enables precise measurement of hydrogen loading in the films using pressure difference. Preliminary tests of loading on scandium films were carried out and some results are presented. In order to optimize the film thickness simulations were carried out using MC-SET code for beta flux emission. The results of the simulations for titanium and palladium film are presented.

Characterization of Coatings by SEM Based Microdiffraction

2011 ◽  
Vol 702-703 ◽  
pp. 570-573
Author(s):  
Ravi C. Gundakaram ◽  
Sai Pramod Pemmasani
Keyword(s):  
Multilayer Coating ◽  
Deposition Process ◽  
Compositional Variation ◽  
Structure Property ◽  
Simple Method ◽  
Combined Use ◽  
Set Up ◽  
Microstructural Studies ◽  
Comprehensive Study

The behaviour of a coating is directly related to its microstructure as well as the crystal structure and composition of different phases that are formed in the deposition process. A comprehensive study of the microstructure and local phase assembly in coatings would help in arriving at structure-property correlations that can help understand the coating behaviour. SEM-based diffraction techniques provide a simple method for obtaining local crystallographic information without the need for complex synchrotron sources. In this study, we present a method for characterization of coatings using SEM-based microdiffraction which involves the combined use of the EDS and EBSD capabilities, citing a Ti-Al-Cr-N multilayer coating as an example. The different layers in the coating were observed and the electron beam focused in each region to first obtain Energy Dispersive Spectra and electron backscatter patterns (EBSPs). The elemental constituents were identified from EDS maps and used to shortlist the possible phases present. The diffraction pattern for each possible phase was then calculated and the EBSPs of the observed and calculated patterns were compared for the closest match. The identified phase was then used as an input to set up EBSD scans across the coating. A qualitative picture of the compositional variation in multilayer coatings was obtained that could help in arriving at the exact stoichiometry of the different layers. Hence, SEM-based microdiffraction allows identification of local crystallographic phases and composition, permitting detailed microstructural studies that would find special application in the study of coatings.

Magnetic interference testing method for an electric fixed-wing unmanned aircraft system (UAS)

2018 ◽  
Vol 6 (3) ◽  
pp. 177-194 ◽  
Author(s):  
L. Tuck ◽  
C. Samson ◽  
J. Laliberté ◽  
M. Wells ◽  
F. Bélanger
Keyword(s):  
Unmanned Aircraft ◽  
Unmanned Aircraft Systems ◽  
Magnetic Intensity ◽  
Testing Method ◽  
Interference Level ◽  
Recorded Data ◽  
Aircraft System ◽  
Control Surfaces

One of the barriers preventing unmanned aircraft systems (UASs) from having a larger presence in the geophysical magnetic surveying industry is the magnetic interference generated by the UAS and its impact on the quality of the recorded data. Detailed characterization of interference effects is therefore needed before remedial solutions can be proposed. A method for characterizing magnetic interference is demonstrated for a 21 kg, 3.7 m wingspan, 6 kW electric fixed-wing UAS purposely built for magnetic surveying. It involves mapping the spatial variations of the total magnetic intensity resulting from the interference sources on the UAS. Dynamic tests showed that the motor should be engaged and the aircraft control surfaces levelled prior to mapping. Experimental results reveal that the two strongest sources of magnetic interference are the cables connecting the motor to the batteries, and the servos. Combining three factors to assess the level of magnetic interference — the total magnetic intensity, 4th difference and vertical magnetic gradient — an index overlay shows that the magnetic sensor(s) should be located at least 50 cm away from the wingtips or tail to ensure an interference level of <2 nT, a 4th difference of <0.05 nT, and a gradient of <10 nT/m.

Inter and Intrablade Row Laser Velocimetry Studies of Gas Turbine Compressor Flows

1988 ◽  
Vol 110 (3) ◽  
pp. 369-376 ◽  
Author(s):  
M. C. Williams
Keyword(s):  
Data Acquisition ◽  
Gas Turbine ◽  
Data Acquisition System ◽  
Acquisition System ◽  
Fan Studies ◽  
Data Rates ◽  
Recorded Data ◽  
Multistage Compressor ◽  
Gas Turbine Compressor

Characterization of the aerodynamics of the flows within gas turbine intrablade passages requires the development of sensitive laser-Doppler velocimeters, a data acquisition system capable of efficiently and accurately handling substantial quantities of data, and appropriate methods of posttest data analysis and display to maximize the value of the recorded data. Pratt & Whitney developed a confocal LDV and data acquisition system that were first employed in the mid-1970s for gas turbine intrablade fan studies. Experience gained through use of the instruments in several aerodynamic studies has provided the basis for the development of a second generation system. The performance of the recently enhanced instrument configured as a single-component LDV has been demonstrated by a NASA-sponsored fan study in which approximately 200 million valid velocity signals were rapidly acquired. The high resolution and data rates achieved permitted detailed mappings of the flow at a variety of conditions and locations. Following this successful study, a second NASA-sponsored program was initiated to assess the feasibility of utilizing this LDV capability to perform detailed stator–rotor interaction studies in a multistage compressor. The equipment employed in these studies will be described and data typical of the findings will be presented.

scholarly journals A comprehensive study on structure, properties, synthesis and characterization of ferrites

2020 ◽  
Vol 7 (6) ◽  
pp. 800-835
Author(s):  
Ajitanshu Vedrtnam ◽  
◽  
Kishor Kalauni ◽  
Sunil Dubey ◽  
Aman Kumar ◽  
...  
Keyword(s):  
Synthesis And Characterization ◽  
Structure Properties ◽  
Comprehensive Study
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