Engineering Commons^™

Planning Freeform Extrusion Fabrication Processes With Consideration Of Horizontal Staircase Effect, Amir Ghazanfari, Wenbin Li, Ming Leu, Robert Landers

Faculty Publications, Mechanical Engineering

An algorithm has been developed to estimate the “horizontal” staircase effect and a technique is proposed to reduce this type of geometrical error for freeform extrusion fabrication processes of 3D “solid” parts. The adaptive rastering technique, proposed in this paper, analyzes the geometry of each layer and changes the width of each line of the raster adaptively in order to reduce the staircase error and increase the productivity simultaneously. For each line, the maximum width that results in a staircase error smaller than a predefined threshold is determined for decreasing the fabrication time or increasing the dimensional accuracy, or both. …

The Contribution Of Non-Thermal And Advanced Oxidation Technologies Towards Dissipation Of Pesticide Residues, N. Misra

Articles

Background

The use of pesticides has stabilised the food production to a great extent and their usage cannot be avoided anymore. Nevertheless, common food processing operations always allowed dissipating pesticide residues in foods to some extent. Within the food science community and the food processing sector, non-thermal food technologies are being researched and commercialised at a great pace over the past three decades.

Scope and Approach

In this review we provide a critical analysis of the literature pertinent to the fate of pesticide residues during non-thermal processing of solid and liquid foods. We also identify the opportunities for further development …

Comparison Of Cost Function Against Positional Analysis For Automated Tracking Of Three-Cell Interactions, Ye He

Dissertations - ALL

Localization and tracking of cells generates raw digital information from microscopy images, including images of stained nuclei and highly precise determination of central positions of cells, which can be analyzed for investigation of cell motility. In a previous study by this group, an algorithm termed automated contour-based tracking for in vitro environments (ACTIVE) was established for tracking large cell populations for long periods of time. For the two-cell interaction events on which ACTIVE was initially focused, error rate was reduced as much as 43% compared to a traditional positional analysis algorithm by Kilfoil and colleagues. In the present thesis, we …

Indium Telluride (In2te3) Semiconductor Cylinder Fiber Sensor, Xun Huang

Dissertations - ALL

Sensors play a very important role in control, monitor and security system. More and more novel technology has been used on a variety of sensors. This thesis investigates using semiconductor cylinder fiber as a new kind of fiber sensor.

Our main motive to do this research is based on my interest in optical fiber. After I did some experiments on the semiconductor cylinder fiber, I found some interesting characteristics. When we changed some environmental conditions around the fiber, the output light from it would change accordingly. So I did a systematic research on it.

This project uses In2Te3 as a …

Mechanically Active Electrospun Materials, Jaimee Marie Robertson

Dissertations - ALL

Electrospinning, a technique used to fabricate small diameter polymer fibers, has been employed to develop unique, active materials falling under two categories: (1) shape memory elastomeric composites (SMECs) and (2) water responsive fiber mats. (1) Previous work has characterized in detail the properties and behavior of traditional SMECs with isotropic fibers embedded in an elastomer matrix. The current work has two goals: (i) characterize laminated anisotropic SMECs and (ii) develop a fabrication process that is scalable for commercial SMEC manufacturing. The former ((i)) requires electrospinning aligned polymer fibers. The aligned fibers are similarly embedded in an elastomer matrix and stacked …

Is “Green Dot” Always The Optimum Engines-Out Glide Speed On The Airbus A320 Aircraft?, Kivanc A. Avrenli, Barry J. Dempsey

Journal of Aviation/Aerospace Education & Research

The dual-engine failure checklist of the Airbus A320 states that the optimum airspeed at which the aircraft can be flown is the “green dot” speed when an engine restart is considered impossible. This is because the “green dot” speed maximizes the power-off glide range in wings-level flight. However, it is not known whether the “green dot” speed would still be the optimum airspeed if the power-off landing maneuver primarily consists of sharp turns. The objective of this study is to find out the optimum power-off glide speed for the A320 if the emergency landing maneuver primarily requires sharp turns rather …

Identification And Exploitation Of Inadvertent Spectral Artifacts In Digital Audio, N. C. Donnangelo, W. S. Kuklinski, R. Szabo, R. A. Coury, G. R. Hamshar

Journal of Digital Forensics, Security and Law

We show that modulation products from local oscillators in a variety of commercial camcorders are coupled into the recorded audio track, creating narrow band time invariant spectral features. These spectral features, left largely intact by transcoding, compression and other forms of audiovisual post processing, can encode characteristics of specific camcorders used to capture the audio files, including the make and model. Using data sets both downloaded from YouTube and collected under controlled laboratory conditions we demonstrate an average probability of detection (Pd) approaching 0.95 for identification of a specific camcorder in a population of thousands of similar recordings, with a …

Computer Forensic Projects For Accountants, Grover S. Kearns

Journal of Digital Forensics, Security and Law

Digital attacks on organizations are becoming more common and more sophisticated. Firms are interested in providing data security and having an effective means to respond to attacks. Accountants possess important investigative and analytical skills that serve to uncover fraud in forensic investigations. Some accounting students take courses in forensic accounting but few colleges offer a course in computer forensics for accountants. Educators wishing to develop such a course may find developing the curriculum daunting. A major element of such a course is the use of forensic software. This paper argues the importance of computer forensics to accounting students and offers …

Data Loss Prevention Management And Control: Inside Activity Incident Monitoring, Identification, And Tracking In Healthcare Enterprise Environments, Manghui Tu, Kimberly Spoa-Harty, Liangliang Xiao

Journal of Digital Forensics, Security and Law

As healthcare data are pushed online, consumers have raised big concerns on the breach of their personal information. Law and regulations have placed businesses and public organizations under obligations to take actions to prevent data breach. Among various threats, insider threats have been identified to be a major threat on data loss. Thus, effective mechanisms to control insider threats on data loss are urgently needed. The objective of this research is to address data loss prevention challenges in healthcare enterprise environment. First, a novel approach is provided to model internal threat, specifically inside activities. With inside activities modeling, data …

Rules Of Professional Responsibility In Digital Forensics: A Comparative Analysis, Filipo Sharevski

Journal of Digital Forensics, Security and Law

The consolidation of the rules of professional responsibility as recommended by the Committee on Identifying the Needs of Forensic Sciences Community (2009) accents the establishment of an uniform code of ethics emphasizing the importance of enforceability in strengthening the role the forensic science plays within the criminal justice system. Equally pertinent for the domain of digital forensics, this imperative entails a research commitment in comparing and contrasting the respective codes of ethics to illustrate their “variety, specificity and enforceability” in order to inform the discussion on the regulative aspects of the digital forensic discipline. Accordingly, this paper reviews the professional …

On The Network Performance Of Digital Evidence Acquisition Of Small Scale Devices Over Public Networks, Irvin Homem, Spyridon Dosis

Journal of Digital Forensics, Security and Law

While cybercrime proliferates – becoming more complex and surreptitious on the Internet – the tools and techniques used in performing digital investigations are still largely lagging behind, effectively slowing down law enforcement agencies at large. Real-time remote acquisition of digital evidence over the Internet is still an elusive ideal in the combat against cybercrime. In this paper we briefly describe the architecture of a comprehensive proactive digital investigation system that is termed as the Live Evidence Information Aggregator (LEIA). This system aims at collecting digital evidence from potentially any device in real time over the Internet. Particular focus is made …

The "Bring Your Own Device" Conundrum For Organizations And Investigators: An Examination Of The Policy And Legal Concerns In Light Of Investigatory Challenges, Carla J. Utter, Alan Rea

Journal of Digital Forensics, Security and Law

In recent years, with the expansion of technology and the desire to downsize costs within the corporate culture, the technology trend has steered towards the integration of personally owned mobile devices (i.e. smartphones) within the corporate and enterprise environment. The movement, known as “Bring Your Own Device” (hereinafter referred to as “BYOD”), seeks to minimize or eliminate the need for two separate and distinct mobile devices for one employee. While taken at face value this trend seems favorable, the corporate policy and legal implications of the implementation of BYOD are further complicated by significant investigatory issues that far outweigh the …

Plc Forensics Based On Control Program Logic Change Detection, Ken Yau, Kam-Pui Chow

Journal of Digital Forensics, Security and Law

Supervisory Control and Data Acquisition (SCADA) system is an industrial control automated system. It is built with multiple Programmable Logic Controllers (PLCs). PLC is a special form of microprocessor-based controller with proprietary operating system. Due to the unique architecture of PLC, traditional digital forensic tools are difficult to be applied. In this paper, we propose a program called Control Program Logic Change Detector (CPLCD), it works with a set of Detection Rules (DRs) to detect and record undesired incidents on interfering normal operations of PLC. In order to prove the feasibility of our solution, we set up two experiments for …

Factors Influencing Digital Forensic Investigations: Empirical Evaluation Of 12 Years Of Dubai Police Cases, Ibtesam Alawadhi, Janet C. Read, Andrew Marrington, Virginia N. L. Franqueira

Journal of Digital Forensics, Security and Law

In Digital Forensics, the number of person-hours spent on investigation is a key factor which needs to be kept to a minimum whilst also paying close attention to the authenticity of the evidence. The literature describes challenges behind increasing person-hours and identifies several factors which contribute to this phenomenon. This paper reviews these factors and demonstrates that they do not wholly account for increases in investigation time. Using real case records from the Dubai Police, an extensive study explains the contribution of other factors to the increase in person-hours. We conclude this work by emphasizing on several factors affecting the …

Cyber Black Box/Event Data Recorder: Legal And Ethical Perspectives And Challenges With Digital Forensics, Michael Losavio, Pavel Pastukov, Svetlana Polyakova

Journal of Digital Forensics, Security and Law

With ubiquitous computing and the growth of the Internet of Things, there is vast expansion in the deployment and use of event data recording systems in a variety of environments. From the ships’ logs of antiquity through the evolution of personal devices for recording personal and environmental activities, these devices offer rich forensic and evidentiary opportunities that smash against rights of privacy and personality. The technical configurations of these devices provide for greater scope of sensing, interconnection options for local, near, and cloud storage of data, and the possibility of powerful analytics. This creates the unique situation of near-total data …

Two Challenges Of Stealthy Hypervisors Detection: Time Cheating And Data Fluctuations, Igor Korkin

Journal of Digital Forensics, Security and Law

Hardware virtualization technologies play a significant role in cyber security. On the one hand these technologies enhance security levels, by designing a trusted operating system. On the other hand these technologies can be taken up into modern malware which is rather hard to detect. None of the existing methods is able to efficiently detect a hypervisor in the face of countermeasures such as time cheating, temporary self uninstalling, memory hiding etc. New hypervisor detection methods which will be described in this paper can detect a hypervisor under these countermeasures and even count several nested ones. These novel approaches rely on …

Data Extraction On Mtk-Based Android Mobile Phone Forensics, Joe Kong

Journal of Digital Forensics, Security and Law

In conducting criminal investigations it is quite common that forensic examiners need to recover evidentiary data from smartphones used by offenders. However, examiners encountered difficulties in acquiring complete memory dump from MTK Android phones, a popular brand of smartphones, due to a lack of technical knowledge on the phone architecture and that system manuals are not always available. This research will perform tests to capture data from MTK Android phone by applying selected forensic tools and compare their effectiveness by analyzing the extracted results. It is anticipated that a generic extraction tool, once identified, can be used on different brands …

Exploring The Use Of Plc Debugging Tools For Digital Forensic Investigations On Scada Systems, Tina Wu, Jason R.C. Nurse

Journal of Digital Forensics, Security and Law

The Stuxnet malware attack has provided strong evidence for the development of a forensic capability to aid in thorough post-incident investigations. Current live forensic tools are typically used to acquire and examine memory from computers running either Windows or Unix. This makes them incompatible with embedded devices found on SCADA systems that have their own bespoke operating system. Currently, only a limited number of forensics tools have been developed for SCADA systems, with no development of tools to acquire the program code from PLCs. In this paper, we explore this problem with two main hypotheses in mind. Our first hypothesis …

Forensic Acquisition Of Imvu: A Case Study, Robert Van Voorst, M-Tahar Kechadi, Nhien-An Le-Khac

Journal of Digital Forensics, Security and Law

There are many applications available for personal computers and mobile devices that facilitate users in meeting potential partners. There is, however, a risk associated with the level of anonymity on using instant message applications, because there exists the potential for predators to attract and lure vulnerable users. Today Instant Messaging within a Virtual Universe (IMVU) combines custom avatars, chat or instant message (IM), community, content creation, commerce, and anonymity. IMVU is also being exploited by criminals to commit a wide variety of offenses. However, there are very few researches on digital forensic acquisition of IMVU applications. In this paper, we …

Tracking And Taxonomy Of Cyberlocker Link Sharers Based On Behavior Analysis, Xiao-Xi Fan, Kam-Pui Chow

Journal of Digital Forensics, Security and Law

The growing popularity of cyberlocker service has led to significant impact on the Internet that it is considered as one of the biggest contributors to the global Internet traffic estimated to be illegally traded content. Due to the anonymity property of cyberlocker, it is difficult for investigators to track user identity directly on cyberlocker site. In order to find the potential relationships between cyberlocker users, we propose a framework to collect cyberlocker related data from public forums where cyberlocker users usually distribute cyberlocker links for others to download and identity information can be gathered easily. Different kinds of sharing behaviors …

A Survey Of Botnet Detection Techniques By Command And Control Infrastructure, Thomas S. Hyslip, Jason M. Pittman

Journal of Digital Forensics, Security and Law

Botnets have evolved to become one of the most serious threats to the Internet and there is substantial research on both botnets and botnet detection techniques. This survey reviewed the history of botnets and botnet detection techniques. The survey showed traditional botnet detection techniques rely on passive techniques, primarily honeypots, and that honeypots are not effective at detecting peer-to-peer and other decentralized botnets. Furthermore, the detection techniques aimed at decentralized and peer-to-peer botnets focus on detecting communications between the infected bots. Recent research has shown hierarchical clustering of flow data and machine learning are effective techniques for detecting botnet peer-to-peer …

Fabrication And Characterization Of Anode-Supported Micro-Tubular Solide Oxide Fuel Cell By Phase Inversion Method, Cong Ren

Theses and Dissertations

Nowadays, the micro-tubular solid oxide fuel cells (MT-SOFCs), especially the anode supported MT-SOFCs have been extensively developed to be applied for SOFC stacks designation, which can be potentially used for portable power sources and vehicle power supply. To prepare MT-SOFCs with high electrochemical performance, one of the main strategies is to optimize the microstructure of the anode support. Recently, a novel phase inversion method has been applied to prepare the anode support with a unique asymmetrical microstructure, which can improve the electrochemical performance of the MT-SOFCs. Since several process parameters of the phase inversion method can influence the pore formation …

Defect Characterization Of 4h-Sic By Deep Level Transient Spectroscopy (Dlts) And Influence Of Defects On Device Performance, Mohammad Abdul Mannan

Theses and Dissertations

Silicon carbide (SiC) is one of the key materials for high power opto-electronic devices due to its superior material properties over conventional semiconductors (e.g., Si, Ge, GaAs, etc). SiC is also very stable and a highly suitable material for radiation detection at room temperature and above. The availability of detector grade single crystalline bulk SiC is limited by the existing crystal growth techniques which introduce extended and microscopic crystallographic defects during the growth process. Recently, SiC based high-resolution semiconductor detectors for ionizing radiation have attracted world-wide attention due to the availability of high resistive, highly crystalline epitaxial layers with very …

Methods For Determining Grease Service Levels In An Ah-64d Intermediate Gearbox Using On-Board Sensors, Travis Steven Edwards

Theses and Dissertations

The intermediate gearbox (IGB) on the AH-64D was chosen as the subject for this study based on the persistent grease leaks that require grounding aircraft. The aircraft is not currently equipped with a method of detecting grease loss during flight, so techniques for analyzing the usefulness of old metrics and possible new techniques can be tested. The main objective of this study is to use the aircraft’s on-board sensors to develop a method of determining the lubrication level of the IGB. Currently, the most reliable method for detecting a fault on the aircraft is through the use of vibration-based condition …

Development Of Computer Simulation Model For Urban Region Using Xp-Swmm In Savannah, Georgia, Matthew Dale Ricks

Theses and Dissertations

The objective of this thesis was to determine if it is possible to create, calibrate, and validate a computer simulation model given a limited amount of measured data. In June 1999, significant flooding was experienced throughout the Casey Canal North drainage basin in Savannah, Georgia. Time-depth rainfall data from a single gage was recorded for this event, along with peak water surface elevations throughout the basin. The computer model chosen for this application was XP-SWMM, which was approved by the Federal Emergency Management Agency to simulate both one dimensional and two dimensional hydraulic models. XP-SWMM was chosen due to its …

Propagated Image Segmentation Using Edge-Weighted Centroidal Voronoi Tessellation Based Methods, Youjie Zhou

Theses and Dissertations

Propagated image segmentation is the problem of utilizing the existing segmentation of an image for obtaining a new segmentation of, either a neighboring image in a sequence, or the same image but in different scales. We name these two cases as the inter-image propagation and the intra-image propagation respectively. The inter-image propagation is particularly important to material science, where efficient and accurate segmentation of a sequence of 2D serial-sectioned images of 3D material samples is an essential step to understand the underlying micro-structure and related physical properties. For natural images with objects in different scales, the intra-image propagation, where segmentations …

Dual-Band Non-Stationary Channel Modeling For The Air-Ground Channel, Ruoyu Sun

Theses and Dissertations

Multiple air-to-ground (AG) radio propagation channels are experimentally characterized for two frequency bands, C-band and L-band. These characterizations are aimed to support the specification of the control and non-payload communication (CNPC) links being designed for civil unmanned aircraft systems (UAS). The use of UAS is expected to grow dramatically in the coming decades. In the United States, UAS will be monitored and guided in their operation within the national airspace system (NAS) via the CNPC link. The specifications of the CNPC link are being designed by government, industries, academia and standards bodies such as the Radio Technical Commission for Aeronautics …

Achieving Reliable Generation \& Delivery Of Energy Through Robust Optimization, Anna Danandeh

USF Tampa Graduate Theses and Dissertations

In this dissertation, we elaborate on the inherent risks and uncertainties in power systems and associated industries, and develop practical solution methods to eliminate their adverse effects.

our research agenda consists of practice-driven problems in different stages of power generation as follows. (1) Affordable fuel procurement through developing a comprehensive fuel supply chain design and operations planning system for electricity generation companies, (2) reliable electricity generation through incorporating dynamic asset rating concept in the unit commitment problem, and (3) efficient demand management through proposing a job scheduling model for effective local generation consumption.

Since reliability cannot be compromised in energy …

Analysis And Energy Reduction Of Humanoid Robot Motions – Stand Up And Sit Down, Ercan Elibol

USF Tampa Graduate Theses and Dissertations

This research studies the electrical power reduction and control analysis of various motion tasks of a humanoid robot. These motions include standing up and sitting down. Each motion’s tasks have their stable and unstable phases throughout the complete motion cycle. Unstable phases can be caused by gravity forces and improper handling of the upper body of the humanoid robot leaning too forward or backward. Even though most of the dynamic motions seem to be accomplished very simply by humans; standing up and sitting down could create challenges for humanoid robots. Some of the critical challenges researches face are: dynamic nature …

Rf Mems Resonators For Mass Sensing Applications, Ivan Fernando Rivera

USF Tampa Graduate Theses and Dissertations

Sensing devices developed upon resonant microelectromechanical and nanoelectromechanical (M/NEMS) system technology have become one of the most attractive areas of research over the past decade. These devices make exceptional sensing platforms because of their miniscule dimensions and resonant modes of operation, which are found to be extremely sensitive to added mass. Along their unique sensing attributes, they also offer foundry compatible microfabrication processes, low DC power consumption, and CMOS integration compatibility. In this work, electrostatically and piezoelectrically actuated RF MEMS bulk resonators have been investigated for mass sensing applications. The capacitively-transduced resonators employed electrostatic actuation to achieve desired resonance mode …