Simulation for Microwave Nondestructive Detection of Thickness and Delamination in Layered-Dielectric in Metallic Substrate

2011 ◽  
Vol 346 ◽  
pp. 764-771 ◽  
Author(s):  
Yu E Yang ◽  
Cun Fu He ◽  
Bin Wu
Keyword(s):  
Experimental Study ◽  
Dielectric Materials ◽  
Nondestructive Inspection ◽  
Metallic Substrate ◽  
Low Loss ◽  
Detection Frequency ◽  
The Media ◽  
Layered Dielectric ◽  
Inspection Techniques ◽  
Effective Reflection Coefficient

Microwaves penetrate inside of low loss dielectric materials and they are sensitive to the presence of internal interfaces and non-uniformities. This allows microwave nondestructive inspection techniques to be utilized for inspecting dielectric in metallic substrate. This article simulated Microwave inspecting thickness and delamination in layered-dielectric in metallic substrate, using open-ended rectangular waveguide probe. Effective reflection coefficient of microwave is used in the detection and evaluation to thickness or delimination in the media. This paper optimized the detection frequency and standoff, which provide a reference for the experimental study.

Low‐loss microwave cavity using layered‐dielectric materials

1994 ◽  
Vol 64 (11) ◽  
pp. 1451-1453 ◽  
Author(s):  
C. J. Maggiore ◽  
A. M. Clogston ◽  
G. Spalek ◽  
W. C. Sailor ◽  
F. M. Mueller
Keyword(s):  
Dielectric Materials ◽  
Microwave Cavity ◽  
Low Loss ◽  
Layered Dielectric

scholarly journals The differential effects of related and unrelated emotions on judgments about media messages

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Rinaldo Kühne ◽  
Claudia Poggiolini ◽  
Werner Wirth
Keyword(s):  
Experimental Study ◽  
Interaction Effect ◽  
News Article ◽  
Differential Effects ◽  
Media Messages ◽  
Processing Depth ◽  
Main Effect ◽  
The Media ◽  
Media Message

AbstractThe present study investigated the influence of related and unrelated emotions on judgments about a news article. An experimental study was designed to manipulate both the relatedness of an elicited emotion (i. e., anger) to the news article and processing depth. Following mood and emotion effects theory, related anger was expected to have a stronger effect on judgments about the media message than unrelated anger. Processing depth was expected to moderate this effect. The results showed a main effect of relatedness and a main effect of processing depth, but the interaction effect was not found. Implications of the findings for understanding how emotions influence the processing of media stimuli are discussed.

Permittivity measurements of low-loss dielectric materials at 60 GHz

1996 ◽  
Author(s):  
Chriss A. Jones ◽  
John H. Grosvenor ◽  
Yehuda Kantor
Keyword(s):  
Dielectric Materials ◽  
60 Ghz ◽  
Low Loss ◽  
Permittivity Measurements

Nondestructive Inspection Methods for Railroad Castings

2010 ◽  
Author(s):  
Daniel Carter ◽  
Kari Gonzales
Keyword(s):  
Magnetic Particle ◽  
Phased Array ◽  
Field Tests ◽  
Ultrasonic Pulse ◽  
Nondestructive Inspection ◽  
Inspection Method ◽  
Technology Center ◽  
Pulse Echo ◽  
Inspection Techniques

Transportation Technology Center, Inc. (TTCI) has investigated various nondestructive inspection (NDI) methods to determine if they are capable of reliably inspecting side frames, bolsters, knuckles, and couplers. The NDI methods used for this investigation include dry and wet (fluorescent) magnetic particle, liquid penetrant, alcohol wipe, visual, ultrasonic (pulse-echo and phased array), and radiography. Inspection results from all methods were used to determine which methods produced repeatable results. From the initial inspection analysis, TTCI engineers determined that the magnetic particle inspection method is the most capable for detecting defects in railroad castings. Further investigation of the magnetic particle technique was completed to develop reliable inspection methods for use on bolsters, side frames, knuckles, and couplers. Each of the inspection techniques have been used for inspections in the field. Using the results of the field tests, procedures were developed by TTCI and submitted to the Association of American Railroads’ (AAR) Coupling Systems and Truck Castings Committee for review and implementation. The inspection procedures can be used by manufacturers, railroads, and car repair shops. Limitations of the inspection procedures include the amount of time necessary to perform the inspection and the reliability of detecting certain types of defects below the surface of the casting. Although these limitations exist, the procedures developed by TTCI are expected to improve the quality of in-service castings and reduce the number of train partings and derailments due to broken or cracked components.

LOW LOSS DIELECTRIC MATERIALS FOR HIGH FREQUENCY APPLICATIONS

2009 ◽  
Vol 23 (17) ◽  
pp. 3649-3654 ◽  
Author(s):  
MOHAN V. JACOB
Keyword(s):  
High Frequency ◽  
Room Temperature ◽  
Low Cost ◽  
Dielectric Materials ◽  
Dielectric Constants ◽  
Transmission Losses ◽  
Low Loss ◽  
Microwave Characterization ◽  
Materials Used ◽  
Low Temperature Electronics

The microwave properties of some of the low cost materials which can be used in high frequency applications with low transmission losses are investigated in this paper. One of the most accurate microwave characterization techniques, Split Post Dielectric Resonator technique (SPDR) is used for the experimental investigation. The dielectric constants of the 3 materials scrutinized at room temperature and at 10K are 3.65, 2.42, 3.61 and 3.58, 2.48, 3.59 respectively. The corresponding loss tangent values are 0.00370, 0.0015, 0.0042 and 0.0025, 0.0009, 0.0025. The high frequency transmission losses are comparable with many of the conventional materials used in low temperature electronics and hence these materials could be implemented in such applications.

scholarly journals Development of Microwave Slow-Wave Comb Applicators for Soil Treatment at Frequencies 2.45 and 0.922 GHz (Theory, Design, and Experimental Study)

Agriculture ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 604
Author(s):  
Graham Brodie ◽  
Yuriy Pchelnikov ◽  
Grigory Torgovnikov
Keyword(s):  
Experimental Study ◽  
Slow Wave ◽  
Dielectric Materials ◽  
Soil Treatment ◽  
Weed Seed ◽  
Surface Layers ◽  
Heat Surface ◽  
Agricultural Applications ◽  
Pathogen Control ◽  
Theoretical Analyses

In agriculture and industry, it is often necessary to heat surface layers of material like soil, timber, concrete, and so on, with microwave (MW) energy. Traditional MW irradiators (antennas) cannot restrain their heating to the surface, with the energy penetrating deeply into the material. Slow-wave comb applicators can provide the required energy distribution in the surface layer. Theoretical analyses of the comb applicators used for heating were carried out and on this basis, three comb applicators were designed and made for soil treatment: two applicators Comb 1 and Comb 2 for frequency 2.45 GHz and Comb 3 for frequency 0.922 GHz. An experimental study of applicators was carried out using two MW plants: 30 kW (2.45 GHz) and 60 kW (0.922 GHz) for heating soil with moisture content in the range from 32% to 173% and density 460 to 1290 kg m−3. The study showed that comb applicators provide the following advantages: reduction in energy dissipation in material depth and release of the significant part of applied MW energy in layers close to the applicator surface. Comb applicators can provide the required soil top layer treatment (sterilization) with reasonable efficiency and can be recommended for practical use in shallow soil treatment for weed seed and pathogen control in agricultural applications. Comb applicators can also be used for effective heating and MW treatment of the surface layers of wood, concrete, bricks, plastics, and other dielectric materials.

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