Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Engineering (3206)
- Physical Sciences and Mathematics (3078)
- Computer Sciences (1283)
- Physics (961)
- Electrical and Computer Engineering (887)
-
- Aerospace Engineering (787)
- Operations Research, Systems Engineering and Industrial Engineering (741)
- Operational Research (422)
- Business (409)
- Optics (349)
- Signal Processing (343)
- Oceanography and Atmospheric Sciences and Meteorology (284)
- Computer Engineering (243)
- Atomic, Molecular and Optical Physics (211)
- Electrical and Electronics (209)
- Environmental Sciences (194)
- Applied Mathematics (189)
- Civil and Environmental Engineering (188)
- Aviation (187)
- Statistics and Probability (185)
- Information Security (181)
- Social and Behavioral Sciences (170)
- Atmospheric Sciences (167)
- Materials Science and Engineering (167)
- Navigation, Guidance, Control and Dynamics (167)
- Plasma and Beam Physics (156)
- Operations and Supply Chain Management (149)
- Electromagnetics and Photonics (142)
- Artificial Intelligence and Robotics (138)
- Other Operations Research, Systems Engineering and Industrial Engineering (126)
- Keyword
-
- #antcenter (259)
- Machine learning (95)
- #csra (73)
- Algorithms (60)
- Kalman filtering (52)
-
- Computer networks--Security measures (51)
- Image processing (50)
- Neural networks (Computer science) (50)
- Computer security (47)
- Software engineering (47)
- Decision making (45)
- Target acquisition (45)
- Global Positioning System (44)
- Optimization (41)
- Adaptive optics (40)
- Neural networks (40)
- #ctisr (38)
- Remote sensing (36)
- Computer vision (35)
- Drone aircraft (35)
- Synthetic aperture radar (34)
- #afcec (33)
- Artificial intelligence (31)
- Atmospheric turbulence (30)
- Genetic algorithms (29)
- Mathematical optimization (29)
- Flight control (28)
- Object-oriented programming (Computer science) (28)
- Wireless communication systems (28)
- Deep learning (27)
- Publication Year
- Publication
- Publication Type
- File Type
Articles 2311 - 2340 of 5606
Full-Text Articles in Entire DC Network
Characterization And Measurements From The Infrared Grazing Angle Reflectometer, Michael R. Benson
Characterization And Measurements From The Infrared Grazing Angle Reflectometer, Michael R. Benson
Theses and Dissertations
A commonly used metric for measuring the reflective properties of a sample is Directional Hemispherical Reflectance (DHR). The Infrared Grazing Angle Reflectometer measures DHR at high angles of incidence. To facilitate this measurement, a novel three dimensional multi-face pyroelectric detector is used. This detector can theoretically measure better than 98% of the light reflected by the sample, regardless of the diffusivity of the sample measured. The setup of this equipment is discussed, and the procedure for calibration is derived. Several of the difficulties in performing measurements are described, and several sample measurements are discussed.
Calibration Of A Silver Detector Using A Pube Source, Melanie E. Mace
Calibration Of A Silver Detector Using A Pube Source, Melanie E. Mace
Theses and Dissertations
During the initial design of the Field Reversed Compression and Heating Experiment (FRCHX), magnetohydrodynamic simulations performed by Los Alamos National Laboratory using MACH2 predicted a neutron yield on the order of 1012 neutrons. However, Air Force Research Laboratory (AFRL) measurements indicate a total of 107-108 neutrons are generated from the FRCHX. A PuBe source was used to create a burst of neutrons to calibrate an AFRL silver detector based on distance to determine if the four order of magnitude discrepancy was cause by an improperly calibrated detector. It was determined that the calibration equation in use …
Application Of An Imaging Fourier-Transform Spectrometer For The Means Of Combustion Diagnostics, Michael R. Rhoby
Application Of An Imaging Fourier-Transform Spectrometer For The Means Of Combustion Diagnostics, Michael R. Rhoby
Theses and Dissertations
A passive remote sensing technique for accurately monitoring the combustion efficiency of petrochemical flares is greatly desired. A Phase II DOE-funded SBIR lead by Spectral Sciences, Inc. is underway to develop such a method. This paper presents an overview of the progress of AFIT's contribution. A Telops Hyper-Cam Mid-wave infrared imaging Fourier-transform spectrometer is used to examine a flame produced by a Hencken burner. Ethylene fuel was burned at four different equivalency ratios φ = 0:80; 0:91; 1:0 and 1:25. Presented is qualitative spectrally-resolved visualization of a Hencken burner flame and the spatial distribution of combustion by-products. The flame spectra …
Adaptive Routing Algorithm For Priority Flows In A Network, Timothy J. Carbino
Adaptive Routing Algorithm For Priority Flows In A Network, Timothy J. Carbino
Theses and Dissertations
This research presents the development of an Adaptive Routing Algorithm for Priority (ARAP) flows in a Network. Devices in today's battle space require information to function. Additional bandwidth requirements for such devices place an increased burden on the already congested networks in the battle space. Some devices require real time information (high priority) and other devices will not require real time information (low priority). Existing protocols treat the network like an opaque entity and have little knowledge of user requirements. User requirement information is available in tactical networks and we can take advantage of the known requirements to better optimize …
A Quantitative Methodology For Vetting "Dark Network" Intelligence Sources For Social Network Analysis, James F. Morris
A Quantitative Methodology For Vetting "Dark Network" Intelligence Sources For Social Network Analysis, James F. Morris
Theses and Dissertations
Social network analysis (SNA) is used by the DoD to describe and analyze social networks, leading to recommendations for operational decisions. However, social network models are constructed from various information sources of indeterminate reliability. Inclusion of unreliable information can lead to incorrect models resulting in flawed analysis and decisions. This research develops a methodology to assist the analyst by quantitatively identifying and categorizing information sources so that determinations on including or excluding provided data can be made. This research pursued three main thrusts. It consolidated binary similarity measures to determine social network information sources' concordance and developed a methodology to …
Short Message Service (Sms) Command And Control (C2) Awareness In Android-Based Smartphones Using Kernel-Level Auditing, Robert J. Olipane
Short Message Service (Sms) Command And Control (C2) Awareness In Android-Based Smartphones Using Kernel-Level Auditing, Robert J. Olipane
Theses and Dissertations
This thesis addresses the emerging threat of botnets in the smartphone domain and focuses on the Android platform and botnets using short message service (SMS) as the command and control (C2) channel. With any botnet, C2 is the most important component contributing to its overall resilience, stealthiness, and effectiveness. This thesis develops a passive host-based approach for identifying covert SMS traffic and providing awareness to the user. Modifying the kernel and implementing this awareness mechanism is achieved by developing and inserting a loadable kernel module that logs all inbound SMS messages as they are sent from the baseband radio to …
Quest Hierarchy For Hyperspectral Face Recognition, David M. Ryer, Trevor J. Bihl, Kenneth W. Bauer Jr., Steven K. Rogers
Quest Hierarchy For Hyperspectral Face Recognition, David M. Ryer, Trevor J. Bihl, Kenneth W. Bauer Jr., Steven K. Rogers
Faculty Publications
A qualia exploitation of sensor technology (QUEST) motivated architecture using algorithm fusion and adaptive feedback loops for face recognition for hyperspectral imagery (HSI) is presented. QUEST seeks to develop a general purpose computational intelligence system that captures the beneficial engineering aspects of qualia-based solutions. Qualia-based approaches are constructed from subjective representations and have the ability to detect, distinguish, and characterize entities in the environment Adaptive feedback loops are implemented that enhance performance by reducing candidate subjects in the gallery and by injecting additional probe images during the matching process. The architecture presented provides a framework for exploring more advanced integration …
Converting Three-Component To Four-Component Image (2012), Ronald S. Cok, Michael E. Miller
Converting Three-Component To Four-Component Image (2012), Ronald S. Cok, Michael E. Miller
AFIT Patents
A method of converting a three-or-more-color-component image input signal to an image output signal includes acquiring an input signal having a plurality of pixel signals, each pixel signal having three, or more, color components; determining a residual difference for each color component of each pixel signal; determining a limit value of the residual differences; calculating a common scale factor for each of the color components based upon the limit value; and applying the common scale factor to the image input signal to produce the image output signal.
Electronic Device, Display And Touch-Sensitive User Interface, Michael E. Miller, Jerald J. Muszak, Michael J. Telek
Electronic Device, Display And Touch-Sensitive User Interface, Michael E. Miller, Jerald J. Muszak, Michael J. Telek
AFIT Patents
Display devices and methods for operating the same are provided. In one embodiment, the display device has an electronic display having an active area for presenting visual content; a housing holding the electronic display and having an opening allowing a person to view a first portion of the active area; and a bezel about the opening, the bezel covering a second portion of the active area and providing a window through which at least a part of the second portion can be viewed. A sensor system senses when a person is close to touching the bezel or when a person …
Low-Loss Meta-Atom For Improved Resonance Response, Derrick Langley, Ronald Coutu Jr., Peter J. Collins
Low-Loss Meta-Atom For Improved Resonance Response, Derrick Langley, Ronald Coutu Jr., Peter J. Collins
Faculty Publications
Measurements of a meta-atom integrated with a low noise amplifier into the split-ring resonator are presented. A comparison is made between baseline meta-atoms and one integrated with a GaAs low noise amplifier. S-parameter measurements in a RF strip-line show the resonant frequency location. The resonance null is more prominent for the integrated meta-atom. Biasing the low noise amplifier from 0 to 7 VDC showed that the resonant null improved with biasing voltage. As the biasing voltage increases, the transmission null reduced from -11.82 to -23.21 dB for biases from 0 to 7 VDC at resonant frequency.
Using Predictive Analytics To Detect Major Problems In Department Of Defense Acquisition Programs, Austin W. Dowling
Using Predictive Analytics To Detect Major Problems In Department Of Defense Acquisition Programs, Austin W. Dowling
Theses and Dissertations
This research provides program analysts and Department of Defense (DoD) leadership with an approach to identify problems in real-time for acquisition contracts. Specifically, we develop optimization algorithms to detect unusual changes in acquisition programs’ Earned Value data streams. The research is focused on three questions. First, can we predict the contractor provided estimate at complete (EAC)? Second, can we use those predictions to develop an algorithm to determine if a problem will occur in an acquisition program or subprogram? Lastly, can we provide the probability of a problem occurring within a given timeframe? We find three of our models establish …
M + Ng Potential Energy Curves Including Spin-Orbit Coupling For M = K, Rb, Cs And Ng = He, Ne, Ar, Larry Aaron Blank, David E. Weeks, Gary S. Kedziora
M + Ng Potential Energy Curves Including Spin-Orbit Coupling For M = K, Rb, Cs And Ng = He, Ne, Ar, Larry Aaron Blank, David E. Weeks, Gary S. Kedziora
Faculty Publications
X2Σ+1/2 , A2Π1/2, A2Π3/2, and B2Σ+1/2 potential energy curves and associated dipole matrix elements are computed for M + Ng at the spin-orbit multi-reference configuration interaction level, where M = K, Rb, Cs and Ng = He, Ne, Ar. Dissociation energies and equilibrium positions for all minima are identified and corresponding vibrational energy levels are computed. Difference potentials are used together with the quasistatic approximation to estimate the position of satellite peaks of collisionally broadened D2 lines. The comparison of potential energy curves for …
Remote Sensing Phase Fluorimetry Using Mercury Vapor Lamp, Matthew J. Bohn, Michael A. Lundin
Remote Sensing Phase Fluorimetry Using Mercury Vapor Lamp, Matthew J. Bohn, Michael A. Lundin
AFIT Patents
An efficient and portable method for remote detection of a target mineral material through frequency domain fluorimetry, a detection technique that measures the time lag between absorption and emission of photons, thereby determining the lifetime of said target mineral material. As claimed and disclosed in the present invention, mercury vapor lamps, a common source of industrial facility lighting, emit radiation that overlaps the UV/blue absorption spectrum of many fluorophores and may be used as an efficient and portable excitation source for remote frequency domain fluorimetry.
Electro-Luminescent Display Device, Michael E. Miller, Joseph R. Bietry, Ronald S. Cok
Electro-Luminescent Display Device, Michael E. Miller, Joseph R. Bietry, Ronald S. Cok
AFIT Patents
An electro-luminescent display includes a first array of light-emitting elements. Each of these light-emitting elements has an optical element. A second array of light-emitting elements also includes a second optical element different from the first. One or more row lines are electrically connected to either light-emitting elements in the first array of light-emitting elements or light-emitting elements in the second array of light-emitting elements. One or more column lines provide a data signal to the first and second array of light-emitting elements. A driver circuit delivers common information to the light-emitting elements in both the first and second arrays in …
Spatial And Spectral Performance Of A Chromotomosynthetic Hyperspectral Imaging System, Randall L. Bostick, Glen P. Perram
Spatial And Spectral Performance Of A Chromotomosynthetic Hyperspectral Imaging System, Randall L. Bostick, Glen P. Perram
Faculty Publications
The spatial and spectral resolutions achievable by a prototype rotating prism chromotomosynthetic imaging (CTI) system operating in the visible spectrum are described. The instrument creates hyperspectral imagery by collecting a set of 2D images with each spectrally projected at a different rotation angle of the prism. Mathematical reconstruction techniques that have been well tested in the field of medical physics are used to reconstruct the data to produce the 3D hyperspectral image. The instrument operates with a 100 mm focusing lens in the spectral range of 400–900 nm with a field of view of 71.6 mrad and angular resolution of …
Evaluation Of The Thorax Of Manduca Sexta For Flapping-Wing Micro Air Vehicle Applications, Alex C. Hollenbeck
Evaluation Of The Thorax Of Manduca Sexta For Flapping-Wing Micro Air Vehicle Applications, Alex C. Hollenbeck
Theses and Dissertations
The tobacco hornworm hawkmoth (Manduca sexta) provides an excellent model from which to garner knowledge pertaining to the development of a Flapping Wing Micro Air Vehicle (FWMAV). Insect-sized FWMAVs will be used by the future warfighter for reconnaissance, nuclear/chemical/biological hazard sensing, and targeting. One of the major challenges facing FWMAV developers is the energetically demanding nature of low Reynolds flapping flight. Investigating the Manduca sexta thorax/wing flapping mechanism as a mechanical system will provide insight into its inherent efficiency. This thesis examined the energetics of the thorax under static loading and dynamic loading using an innovative load-application technique. It was …
Positron Lifetime Modulation By Electric Field Induced Positronium Formation On A Gold Surface, Daniel J. Higgins
Positron Lifetime Modulation By Electric Field Induced Positronium Formation On A Gold Surface, Daniel J. Higgins
Theses and Dissertations
The purpose of this project is to study the lifetime and annihilation mode of positrons, the antimatter counterpart to electrons, and the formation rate of positronium on a gold surface modified by gold nanoparticles under the influence of radial electric fields measured using two independent systems. The positron annihilation photon pair/triplet spectroscopy system uses a sodium iodide ring detector segmented into six detection regions providing rough position sensitivity to measure the ratio of two to three photon positron annihilation events. An increased rate of three photon annihilation events and a decreased rate of two photon annihilation events are observed when …
The Focusing Of Light Scattered From Diffuse Reflectors Using Phase Modulation, Jessica M. Schafer
The Focusing Of Light Scattered From Diffuse Reflectors Using Phase Modulation, Jessica M. Schafer
Theses and Dissertations
“Indirect photography" was recently demonstrated for imaging hidden scene information through the collection and radiometric modeling of light reflecting off of visible reflecting surfaces. The ability to focus the beam that reflects off the visible surface to a tight spot on the hidden object is theorized to simulate a direct line of sight from the light source to the object, reducing the radiometric model to that of the previously demonstrated dual photography. Experiments involving the focusing of light transmitted through highly scattering media have been adapted to the case of reflection. The focusing of a HeNe laser reflected off diffusely …
Passive Multistatic Radar Imaging Using An Ofdm Based Signal Of Opportunity, Matthew B. P. Rapson
Passive Multistatic Radar Imaging Using An Ofdm Based Signal Of Opportunity, Matthew B. P. Rapson
Theses and Dissertations
This paper demonstrates a proof of concept in using an OFDM-based signal of opportunity for SAR imaging purposes within a passive, multistatic radar construct. Two signal processing methods have been proposed to create phase history data. The same methods are applied in both a simulated software model and an experimental data collection environment to produce simulated SAR images using the CBP imaging algorithm. The images generated from both the experimental and simulated data were observed to be consistent with each other and with expectations in terms of resolution. Coherent addition of the images results in improved image resolution due to …
A Dempster-Shafer Method For Multi-Sensor Fusion, Bethany G. Foley
A Dempster-Shafer Method For Multi-Sensor Fusion, Bethany G. Foley
Theses and Dissertations
The Dempster-Shafer Theory, a generalization of the Bayesian theory, is based on the idea of belief and as such can handle ignorance. When all of the required information is available, many data fusion methods provide a solid approach. Yet, most do not have a good way of dealing with ignorance. In the absence of information, these methods must then make assumptions about the sensor data. However, the real data may not fit well within the assumed model. Consequently, the results are often unsatisfactory and inconsistent. The Dempster-Shafer Theory is not hindered by incomplete models or by the lack of prior …
Decision Analysis Using Value-Focused Thinking For Retention Of Long-Term Officers In The Korean Army, Jaebum Kim
Decision Analysis Using Value-Focused Thinking For Retention Of Long-Term Officers In The Korean Army, Jaebum Kim
Theses and Dissertations
The North Korean attacks on the South Korean naval vessel, the Cheonan, and on the South Korean island of Yeonpyeong in 2010 have resulted in the deterioration of the relationship between North and South Korea. The death of Kim Jong Il in December 2011 has raised serious concerns over the future of North Korea and political stability on the Korean Peninsula. Against this background, South Korea has continued its agenda of military reform to improve the retention and management of its military personnel. However, South Korea needs better methods and measures for evaluating its personnel to distinguish highly qualified officers …
Aircraft Course Optimization Tool Using Gpops Matlab Code, Ryan D. Gauntt
Aircraft Course Optimization Tool Using Gpops Matlab Code, Ryan D. Gauntt
Theses and Dissertations
Aircraft course planning between two points in a clear, no threat environment is easy and straightforward. However, the addition of various threats can greatly increase the difficulty and complexity of course planning. Placing new waypoints along the edge of each threat, mostly skirting the dangerous environment, may not prove too difficult, but such courses are far from optimal. Given aircraft, environment, and time constraints it is likely a much more optimal path exists between any given start and end points. This research focuses on determining the feasibility of using the General Pseudospectral Optimization Software program files written for the MATLAB …
Acquisition Program Problem Detection Using Text Mining Methods, Trevor P. Miller
Acquisition Program Problem Detection Using Text Mining Methods, Trevor P. Miller
Theses and Dissertations
This research provides program analysts and Department of Defense leadership with an approach to identify problems in real-time for acquisition contracts. Specifically, we test the abilities of statistical algorithms using text mining techniques to detect unusual changes in acquisition programs’ cost estimates at the completion of the programs. Currently, the government purchases monthly written reports, an informational tool on status of an acquisition program, but has not been integrated into problem prediction analysis. We center our research on the following two questions: First, can we quantify the qualitative written reports? Second, can we use these quantifications of the texts to …
A Women-Only Comparision Of The U.S. Air Force Fitness Test And The Marine Combat Fitness Test, Tarah D. Mitchell
A Women-Only Comparision Of The U.S. Air Force Fitness Test And The Marine Combat Fitness Test, Tarah D. Mitchell
Theses and Dissertations
In 2009, Captain Thomas Worden determined the Air Force Physical Fitness Test (AFPFT) poorly predicted combat capability for his 86 study participants. With only 5 of these 86 volunteers being women, this limited Worden's findings to primarily men. This follow-on research investigated whether these results carried over to women. We recruited 61 female volunteers and compared their performance on the AFPFT to the Marine Combat Fitness Test, the proxy for combat capability. Like Worden's research, we discovered little association between the two (R2 of 0.161). However, this association significantly increased (adj R2 of 0.572) when utilizing the raw …
Determining Angular Frequency From A Video With A Generalized Fast Fourier Transform, Lindsay N. Smith
Determining Angular Frequency From A Video With A Generalized Fast Fourier Transform, Lindsay N. Smith
Theses and Dissertations
Suppose we are given a video of a rotating object and suppose we want to determine the rate of rotation solely from the video itself and its known frame rate. In this thesis, we present a new mathematical operator called the Geometric Sum Transform (GST) that can help one determine the angular frequency of the object in question. The GST is a generalization of the discrete Fourier transform (DFT) and as such, the two transforms have much in common. However, whereas the DFT is applied to a sequence of scalars, the GST can be applied to a sequence of vectors. …
Satellite Relative Motion Control For Mit's Spheres Program, Samuel P. Barbaro
Satellite Relative Motion Control For Mit's Spheres Program, Samuel P. Barbaro
Theses and Dissertations
Autonomous formation flight concepts and algorithms have great potential to revolutionize spacecraft operations enabling missions to perform autonomous docking, in-space refueling, in-space robotic assembly, and space debris removal. Such tasks require the implementation of speed and path control algorithms to maneuver satellites along relative paths with specified rates along those paths. This thesis uses MATLAB® and SIMULINK® to design and simulate a control algorithm capable of providing relative speed and path control between satellites with a pointing error of less than two degrees, a position error of less than two millimeters, and a millimeter per second of velocity error. The …
Universal Plug-N-Play Sensor Integration For Advanced Navigation, Daniel L. Elsner
Universal Plug-N-Play Sensor Integration For Advanced Navigation, Daniel L. Elsner
Theses and Dissertations
This research investigates the potential for Plug-n-Play sensor integration for navigation and other applications. Specifically, the requirements of such a system are outlined and attempts are made to achieve them using two separate systems: one using Robot Operating System (ROS) as middleware and the other using more traditional software design patterns. The end result is not so much a deliverable in terms of software, but more of a feasibility analysis comparing the two approaches.
Obfuscating Against Side-Channel Power Analysis Using Hiding Techniques For Aes, Austin W. Fritzke
Obfuscating Against Side-Channel Power Analysis Using Hiding Techniques For Aes, Austin W. Fritzke
Theses and Dissertations
The transfer of information has always been an integral part of military and civilian operations, and remains so today. Because not all information we share is public, it is important to secure our data from unwanted parties. Message encryption serves to prevent all but the sender and recipient from viewing any encrypted information as long as the key stays hidden. The Advanced Encryption Standard (AES) is the current industry and military standard for symmetric-key encryption. While AES remains computationally infeasible to break the encrypted message stream, it is susceptible to side-channel attacks if an adversary has access to the appropriate …
Magnesium Object Manager Sandbox, A More Effective Sandbox Method For Windows 7, Martin A. Gilligan
Magnesium Object Manager Sandbox, A More Effective Sandbox Method For Windows 7, Martin A. Gilligan
Theses and Dissertations
A major issue in computer security is limiting the affects a program can have on a computer. One way is to place the program into a sandbox, a limited environment. Many attempts have been made to create a sandbox that maintains the usability of a program and effectively limits the effects of the program. Sandboxes that limit the resources programs can access, have succeeded. To test the effectiveness of a sandbox that limits the resources a program can access on Windows 7, the Magnesium Object Manager Sandbox (MOMS) is created. MOMS uses a kernel mode Windows component to monitor and …
Scalable Wavelet-Based Active Network Stepping Stone Detection, Joseph I. Gilbert
Scalable Wavelet-Based Active Network Stepping Stone Detection, Joseph I. Gilbert
Theses and Dissertations
Network intrusions leverage vulnerable hosts as stepping stones to penetrate deeper into a network and mask malicious actions from detection. This research focuses on a novel active watermark technique using Discrete Wavelet Transformations to mark and detect interactive network sessions. This technique is scalable, nearly invisible and resilient to multi-flow attacks. The watermark is simulated using extracted timestamps from the CAIDA 2009 dataset and replicated in a live environment. The simulation results demonstrate that the technique accurately detects the presence of a watermark at a 5% False Positive and False Negative rate for both the extracted timestamps as well as …