Improved Quantification Of Defect Cross-Section For Active Microwave Thermography

Active microwave thermography (AMT) is an integrated nondestructive testing and evaluation (NDT&E) technique that features a microwave-based excitation and subsequent thermographic inspection via an infrared camera. AMT has been successfully employed in several industries including aerospace and civil for NDT&E inspections. Since the excitation is microwave-based, an antenna is used to irradiate the sample under test and hence the heating pattern will vary spatially (following the antenna pattern). This nonuniform thermal excitation may limit the ability of AMT to quantify defect cross-sections. Therefore, this work seeks to expand the capabilities of AMT by incorporating a post-processing technique to improve defect cross-section quantification. Specifically, an approach based on the temperature gradient is considered, with results compared to other well-established approaches. The effect of noise is also considered. The results, from both simulation and measurement, indicate that the temperature gradient approach provides the least amount of error in defect cross-section quantification

Thermal Diffusivity Materials Characterization Via Active Microwave Thermography

Active microwave thermography (AMT) is a relatively new nondestructive evaluation method which is proposed in this work for thermal materials characterization. Specifically, AMT is investigated as a single-sided measurement option for out-of-plane thermal diffusivity (a parameter traditionally measured using a two-sided technique). Simulation and measurement results support the use of AMT for such a characterization for materials backed by an electromagnetically absorptive material. Both lossless and lossy materials may be measured, with better accuracy for lossless materials. The effect of heating time was also considered. The results indicate that for the 50 W system used here, 100 seconds of electromagnetic illumination is necessary to achieve less than 10% error in measured out-of-plane thermal diffusivity for lossless and lossy materials

Pulsed-Active Microwave Thermography

Active microwave thermography (AMT) is a thermographic nondestructive testing and evaluation technique that utilizes an electromagnetic-based excitation with a subsequent infrared measurement of the surface thermal profile of the material or structure of interest. AMT has been successfully applied to several aerospace and civil infrastructure applications. This work seeks to expand the performance of AMT by incorporating a signal processing technique common to traditional (flash-lamp) thermography, referred to as pulsed thermography (PT). PT operates on the premise of a pulsed excitation, as opposed to a constant or step excitation (ST) over a given time-period that is typical to traditional active thermography. This work applies the pulsed approach to AMT, herein referred to as P-AMT, and compares the thermal contrast (TC) and signal-to-noise ratio (SNR) of traditional and pulsed AMT inspections as applied to a moisture ingress detection need. The results suggest that the optimal heating time (indicated through SNR) for P-AMT is less than that of traditional AMT with a reduced overall (absolute) temperature. This is important as it relates to any inspection with concerns for thermal damage as well an overall reduction in required inspection time

Modified H-Plane Sectoral Horn for FSS Sensing Applications

The Use of Frequency Selective Surfaces (FSSs) as Sensors Has Found Recent Success in the Structural Health Monitoring Realm. FSS Theory Assumes Infinite FSS Dimensions and Planewave Illumination. However, in Practice, an FSS Sensor is Finite, and the Illuminating Field Varies Across the Plane of the Sensor. as Such, it is of Interest to Reduce the Nonuniformity of the Incident Electromagnetic Energy Incident on the Sensor. to This End, This Work Explores the Modification of a Standard H-Plane Sectoral Horn through the Addition of a Ridge to Generate a Uniform Electric Field over a Specified Region of Interest. in Addition to This Modified Antenna, Standard Gain (Pyramidal) and H-Plane Sectoral Horns Were Also Considered for Comparison. the Results Show that Variation in the Electric Field Pattern is Reduced for the Modified Sectoral Horn but at the Cost of Matching Properties

Assessing Student Empathy for Hemodialysis Patients

Hemodialysis is a treatment process utilized by kidney patients to filter their blood. These patients are required to undergo an intensive regimen including hemodialysis treatments multiple times per week lasting 3-5 hours each. As a result of hemodialysis, patients experience decreased autonomy, freedom, and independence. An estimated 50% of these patients do not adhere to their treatment regimen. Patients on hemodialysis may be more compliant to their treatment if they are satisfied with the level of care and empathy they perceive from their healthcare providers. Currently there is no literature measuring empathy levels of healthcare professionals or students towards patients on hemodialysis. Examining student empathy levels toward this patient population provides a good representation of future healthcare professional empathy levels. Attitudes developed during school impact the future of patient-focused healthcare and ultimately, patient outcomes. The objectives of this study include: to determine the factors influencing medical, nursing, and pharmacy students; to determine empathy levels for medical, nursing, and pharmacy students; and to design and implement an intervention based on determined factors to increase student empathy in pharmacy students. This study will be conducted in two phases. The first phase involves contacting different medical, nursing, and pharmacy schools in Ohio. We will assess medical, nursing, and pharmacy student’s empathy towards patients on hemodialysis. A survey will be created consisting of the Kiersma Chen Empathy Scale (KCES) to assess empathy and questions addressing factors influencing student empathy. An educational intervention will then be developed in the second phase based on phase one results. The intervention will be implemented in Cedarville University’s School of Pharmacy second year professional students. A pre-post test will be administered to these pharmacy students in order to evaluate the effectiveness of intervention in increasing their empathy levels. Data from phase one will be exported from Qualtrics software to IBM SPSS 22® for statistical analysis. Analysis will be performed to determine possible factors influencing student empathy and compare difference between students in medical, nursing, and pharmacy health professions

Embedded Aperture-Based FSS Sensor

Frequency Selective Surfaces (FSSs) Are Two-Dimensional Periodic Arrays of Electrically Conductive Elements or Apertures that Have a Specific Electromagnetic Reflection And/or Transmission Response. in This Work, an Aperture-Based Sensor Design Was Proposed that is Capable of Sensing Strain When Embedded in a Layered Dielectric Structure (I.e., an Embedded Sensor). an Aperture Approach Was Selected Due to the Potential for Operation in Reflection Mode Without a Conductive Backplane. the Sensor Was Designed to Operate within the K-Band to Improve the Potential Strain Measurement Resolution, as the Unit Cell Dimensions Are Inversely Related to the Operating Frequency and Directly Related to Strain Sensitivity. Simulation Results for the Small-Scale Strain Range of 0-0.5% Are Presented, with a Sensitivity of 20.4 MHz/O.1 % Strain

Pulsed-active microwave thermography

Active microwave thermography (AMT) is a thermographic nondestructive testing and evaluation techniquethat utilizes an electromagnetic-based excitation with a subsequent infrared measurement of the surface thermal profile of the material or structure of interest. AMT has been successfully applied to several aerospace and civil infrastructure applications. This work seeks to expand the performance of AMT by incorporating a signal processing technique common to traditional (flash-lamp) thermography, referred to as pulsed thermography (PT). PT operates on the premise of a pulsed excitation, as opposed to a constant or step excitation (ST) over a given time-period that is typical to traditional active thermography. This work applies the pulsed approach to AMT, herein referred to as P-AMT, and compares the thermal contrast (TC) and signal-to-noise ratio (SNR) of traditional and pulsed AMT inspections as applied to a moisture ingress detection need. The results suggest that the optimal heating time (indicated through SNR) for P-AMT is less than that of traditional AMT with a reduced overall (absolute) temperature. This is important as it relates to any inspection with concerns for thermal damage as well an overall reduction in required inspection time

Speaker- versus listener-oriented disfluency: A re-examination of arguments and assumptions from autism spectrum disorder

We re-evaluate conclusions about disfluency production in high-functioning forms of autism spectrum disorder (HFA). Previous studies examined individuals with HFA to address a theoretical question regarding speaker- and listener-oriented disfluencies. Individuals with HFA tend to be self-centric and have poor pragmatic language skills, and should be less likely to produce listener-oriented disfluency. However, previous studies did not account for individual differences variables that affect disfluency. We show that both matched and unmatched controls produce fewer repairs than individuals with HFA. For silent pauses, there was no difference between matched controls and HFA, but both groups produced more than unmatched controls. These results identify limitations in prior research and shed light on the relationship between autism spectrum disorders and disfluent speech

The role of emotions and physiological arousal in modulating impulsive behaviour.

Impulsivity received considerable attention in the context of drug misuse and certain neuropsychiatric conditions. Because of its great health and well-being importance, it is crucial to understand factors which modulate impulsive behaviour. As a growing body of literature indicates the role of emotional and physiological states in guiding our actions and decisions, we argue that current affective state and physiological arousal exert a significant influence on behavioural impulsivity. As 'impulsivity' is a heterogeneous concept, in this paper, we review key theories of the topic and summarise information about distinct impulsivity subtypes and their methods of assessment, pointing out to the differences between the various components of the construct. Moreover, we review existing literature on the relationship between emotional states, arousal and impulsive behaviour and suggest directions for future research