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Full-Text Articles in Engineering
Effect Of Thermal Treatments On Mechanical Properties And Bioactivity Of Third Generation Of Bioactive Glass. A Step For Commercialization Success Of Third Generation Bioactive Glasses, Rajan Pandya
Theses and Dissertations
Unavailability of donors for transplanting bone to help people with orthopedic imparities gave rise to the metal implants that could be made in factories. This seemed like a good solution as it was available to all the people who needed it. It came with limitations such as restricted movement, infection, wear and tear of the surrounding tissue, and rejection. Biologically active implants were introduced by Dr. Larry Hench in 1960s [12]. The field of regenerative medicine has been changing rapidly since then. Biologically active implants facilitate bone regeneration and do not harm the surrounding tissue in any way. The bioactive …
Holographic-Based Leaky Wave Antennas And Phonon-Enhanced Waveguides For Infrared Applications, Franklin Muriuki Manene
Holographic-Based Leaky Wave Antennas And Phonon-Enhanced Waveguides For Infrared Applications, Franklin Muriuki Manene
Theses and Dissertations
This work contributes to critical requirements for antenna-coupled detection applications: 1) large capture cross section with design control of angular response and 2) long propagation lengths of complex signals. Antenna-coupled detectors for infrared applications provide appreciable capture cross sections while delivering signals to sub-wavelength-sized detectors. In this work, leaky-wave antennas are considered for the first time in the infrared spectrum. Design characterization of angular radiation patterns as well as polarization is presented. While leaky-wave antennas hold great promise for enhancing capture cross section, thus narrowing the field of view of the detector, there is a parallel need to preserve coherent …
Measurement Based Statistical Model For Path Loss Prediction For Relaying Systems Operating In 1900 Mhz Band, Masoud Dao Hamid
Measurement Based Statistical Model For Path Loss Prediction For Relaying Systems Operating In 1900 Mhz Band, Masoud Dao Hamid
Theses and Dissertations
Relays play important role in deployment of Long Term Evolution (LTE) and LTE-Advanced systems. They are used to enhance coverage, throughput and system capacity. The impact of the relay deployment on the network planning has to be modeled so that the above mentioned goals can be achieved. For successful modeling one needs to predict the path loss on the link between an eNodeB and a relay station. The review of literature shows that there is a general shortage of measured data to help empirical understanding of the propagation conditions in relay environment. This dissertation aims at developing empirical path loss …
Gammatone And Mfcc Features In Speaker Recognition, Wison Burgos
Gammatone And Mfcc Features In Speaker Recognition, Wison Burgos
Theses and Dissertations
The feature analysis component of an Automated Speaker Recognition (ASR) system plays a crucial role in the overall performance of the system. There are many feature extraction techniques available, but ultimately we want to maximize the performance of these systems. From this point of view, the algorithms developed to compute feature components are analyzed. Current state-of-the-art ASR systems perform quite well in a controlled environment where the speech signal is noise free. The objective of this thesis investigates the results that can be obtained when you combine Mel-Frequency Cepstral Coefficients (MFCC) and Gammatone Frequency Cepstral Coefficients (GFCC) as feature components …
Airline Consumers’ Perception Of Transport Security Administration’S Prohibited Items, Clayton Ernest D'Souza
Airline Consumers’ Perception Of Transport Security Administration’S Prohibited Items, Clayton Ernest D'Souza
Theses and Dissertations
There has been limited research conducted and significantly limited scholarly articles on consumer attitudes towards the current TSA prohibited items list. If the research were to be conducted a year after the September 11, 2001 attacks, the results of the research would be negatively skewed, indicating the majority of passengers would approve of the TSA prohibited list. But after almost thirteen years since the devastating act of terrorism and no major attempt to repeat a similar terrorist activity, would airline consumers continue to fly if the TSA amended the prohibited items list and allowed passengers to bring on liquids and …
Characterization Of Sinusoidal Vibration Induced Fluid Motion In Spherical Elastomeric Diaphragm Tanks, Cody Ambrose Harris
Characterization Of Sinusoidal Vibration Induced Fluid Motion In Spherical Elastomeric Diaphragm Tanks, Cody Ambrose Harris
Theses and Dissertations
Elastomeric diaphragm tanks are commonly used in spacecraft applications to incite positive expulsion of hydrazine monopropellant. The diaphragm exhibits low flexural rigidity, causing it to easily fold under its own weight at low fill levels. If the tank is sinusoidally oscillated under standard gravity, such as during ground transportation or launch pad winding, these folds will result in rubbing, eventually wearing down the thin material to the point of failure. The ability to accurately predict the presence of folds, rubs, and center of gravity shifts for a given tank design and frequency excitation is thus of critical importance to mission …
Validity And Reliability Of A Mini Situational Judgment Test (Sjt) For Pilots, Lu Shi
Validity And Reliability Of A Mini Situational Judgment Test (Sjt) For Pilots, Lu Shi
Theses and Dissertations
The situational judgment test (SJT) was developed by Hunter (2002) to test pilot judgment. SJT is very useful. However, this test takes too long for participants to complete. A mini SJT was developed with shortened questions. The purpose of this research was to determine the reliability and validity of mini SJT comprised of 16 of the original 51 questions. Validity and reliability were the two key elements in psychometrics. Face validity was used as a method to measure validity. Reliability was determined by Cronbach's Alpha, the correlation of split half and even odd, and Pearson s correlation of test retest. …
Overcoming Hard Problems In Software Testing With Testing As A Service, Brianna Floss
Overcoming Hard Problems In Software Testing With Testing As A Service, Brianna Floss
Theses and Dissertations
Software testing is a crucial phase of the software development lifecycle, responsible for assuring that the system under test meets quality standards, requirements, and consumer needs. Unfortunately, software testing is not without flaws. Some problems are timeless while others are brought on by new technologies and methodologies. As software systems grow in size and complexity, quality becomes significantly more difficult to ensure. With recent advancements in cloud computing, the internet’s vast and elastic resources are available for testing. Testing as a Service (TaaS) offers accessible services that handle testing activities to consumers on a pay-as-you-test basis in hopes of providing …
Design Of A Light-Weight Low-Volume High Oxygen Storage Density Material, Nicholas Robert Schwartz
Design Of A Light-Weight Low-Volume High Oxygen Storage Density Material, Nicholas Robert Schwartz
Theses and Dissertations
A compact, lightweight, dense and safe method for storing and supplying oxygen remains a large hurdle for closed-circuit self-contained breathing apparatus (SCBA) and respiratory protective equipment. No filter that can protect against airborne chemical, biological, radiological, and nuclear (CBRN) contaminants exists, which presents the need for an isolated oxygen source. Heavy and high maintenance oxygen cylinders are typically used. The most important criteria for a smart and effective CBRN protection device are safety, weight, size, and cost, level of maintenance, ease-of-use and reliability. This study focused on nanomaterials for high capacity gas storage. Nanocapillary arrays composed of anodic aluminum oxide …
Infrared Leaky Wave Antenna Coupled Bolometer, Navaneeth Premkumar
Infrared Leaky Wave Antenna Coupled Bolometer, Navaneeth Premkumar
Theses and Dissertations
A four-element infrared leaky-wave antenna coupled bolometer was investigated with the goal of characterizing signal extraction as a long wave infrared (LWIR) detector. Simulations were carried out using Ansys HFSS. Various simple loading techniques were seen and their behavior characterized. A transmission line loaded antenna coupled bolometer was investigated using an incident-wave excitation and angle of sensing inaccuracies were observed. A position pertaining to the design criterion of angular scanning in frequency was then parametrically tuned for. The leaky-wave antenna was then simulated in the transmitting scenario. A waveport fed case was explored and far-field pattern generated. Transmission line losses …
Factors Leading To A Satisfying Career In Airport Management: Evidence From Airport Managers In Norway, Eirik Holdø
Factors Leading To A Satisfying Career In Airport Management: Evidence From Airport Managers In Norway, Eirik Holdø
Theses and Dissertations
The purpose of this study was to identify factors that influence a person to choose airport manager as a professional career and how these factors relate to the level of satisfaction the person experiences with this career choice. By using a correlational methodology with an explanatory design, this study examined the influence of early aviation interests, demographics, health factors, formal education, and other aviation experiences on Norwegian airport managers’ career choice and its relationship to their level of career satisfaction. A sample of N = 39 airport managers at Norwegian commercial service airports were surveyed. To assess the relationship, a …
Qualitative And Quantitative Analyses Of Drivers Attitudes Towards General Usability Of Smart Technology Specific To The Secondary Task Of Texting While Operating A Vehicle, Indira Maharaj
Theses and Dissertations
The purpose of this study was to assess the qualitative and quantitative analyses of driver’s attitudes towards general usability of smart technology specific to the secondary task of texting while operating a vehicle for university students, aged 18-35, at the Florida Institute of Technology main campus in Melbourne, Florida. A mixed methods research design was utilized to gather data. The qualitative data were measured using content analysis, and the quantitative data were measured using descriptive and inferential analyses. The general consensus of both the quantitative and qualitative data showed that the majority of participants were satisfied with using smart technology …
Ascent And Scenario-Based Time Of Useful Consciousness (Tuc), Lenka Cipova
Ascent And Scenario-Based Time Of Useful Consciousness (Tuc), Lenka Cipova
Theses and Dissertations
The Time of Useful Consciousness (TUC) is a standardized table that has been used by aviation regulatory, safety, and manufacturing organizations for over 50 years to better understand the potential danger of cabin depressurization. It emphasizes the importance of the immediate donning of oxygen masks at high altitudes in the event of a cabin depressurization which otherwise would result in the loss of consciousness. The current TUC table was developed from research in high-altitude (hypobaric) chambers by taking the pilots to various high altitudes while wearing oxygen masks at which point they removed their masks and engaged in various psychological …
Analyzing Thermal And Mechanical Effects Of Pulsed Laser Irradiation On Tissues, Mohit Ganguly
Analyzing Thermal And Mechanical Effects Of Pulsed Laser Irradiation On Tissues, Mohit Ganguly
Theses and Dissertations
Pulsed lasers are known for their spatial and temporal specificity in delivering heat energy to the tissues. This is useful in laser ablation treatment mechanism where damage to the healthy tissues is highly undesired. However, the efficacy of the process is limited by the damage caused by the pulsed laser. A pulsed laser has both photothermal and photomechanical interaction with tissues. Photothermal interaction is caused by the rise in temperature due to the laser irradiation. This includes the denaturation of proteins, increased mitochondrial membrane permeability and ultimately vaporization. Photomechanical interaction causes the generation of pressure waves produced as a result …
Resonant Coupling Of An Infrared Metasurface With Pmma, Michael Francis Finch
Resonant Coupling Of An Infrared Metasurface With Pmma, Michael Francis Finch
Theses and Dissertations
Resonance coupling between a metasurface or planar metamaterial and PMMA’s, polymethyl methacrylate, phonon resonance corresponding to the C=O molecular bond at 1733 cm-1 (52 THz) is investigated. Two metasurfaces, nano rod and nano slot, are modeled using ANSYS HFSS and measured material optical properties for gold and PMMA in inferred spectrum. Both metasurfaces exhibited normal mode splitting also known as avoidance crossing, quantum level repulsion, or vacuum Rabi splitting. Normal mode splitting is shown to be a result of coupling between the PMMA phonon resonance and the resonance of the metasurface. Analytical models, which are tied to physical descriptions, are …
Flexible Slosh Diaphragm Modeling And Simulation In Propellant Tanks, Darren Vaughn Levine
Flexible Slosh Diaphragm Modeling And Simulation In Propellant Tanks, Darren Vaughn Levine
Theses and Dissertations
iquid sloshing and propellant distribution is an important field of research for aerospace applications such as launch vehicles and spacecraft. The propellant mass behavior can greatly influence vehicle dynamics, altering trajectories and structural loading distributions. In order to combat these concerns some propellant tanks employ thin elastomeric diaphragms to separate the fuel from the gas volumes and restrict the fluid's motion. The diaphragm’s flexible behavior is generally highly nonlinear, and various propellant fill levels and acceleration conditions can cause large deflections resulting in complex buckling and folding patterns. When complex and non-uniform deformations occur, there is potential for diaphragm wear …