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2016

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Full-Text Articles in Engineering

A Numerical Investigation Of Wellbore Stability Problems Using An Elastoplastic Model, Chang Huang Jan 2016

A Numerical Investigation Of Wellbore Stability Problems Using An Elastoplastic Model, Chang Huang

LSU Master's Theses

Wellbore stability analysis acts an important role in the drilling design to avoid pipe-stuck, lost circulation and the other instability-induced problems. However, the conventional linear elastic model used by the industry is too conservative in predicting the mud weight window. This project is aimed at improving the accuracy of wellbore stability analysis. An elastoplastic model with Drucker-Prager yield criterion featured by strain hardening is proposed to characterize the rock behavior. Object-oriented finite element analysis simulator, NSMOOM, is programmed in MATLAB. The simulator is verified with the analytical solution in the elastic domain and with the commercial software ABAQUS in the …


Calibration Of Resistance Factors Needed In The Lrfd Design Of Drilled Shafts, Alicia Rae Fortier Jan 2016

Calibration Of Resistance Factors Needed In The Lrfd Design Of Drilled Shafts, Alicia Rae Fortier

LSU Master's Theses

This report presents the reliability-based analysis of the calibration of resistance factors for the Load and Resistance Factor Design (LRFD) of axially loaded drilled shafts. AASHTO’s 2012 LRFD Bridge Design Specifications recommends various resistance factors for the design of deep foundations; however, since these values are not specific to any one region, they are very conservative. For Louisiana or Mississippi, the adoption of such recommended resistance factors could substantially increase foundation sizes. Therefore, it is necessary to develop a database of drilled shaft load tests performed in the regions of Louisiana, Mississippi, and surrounding states with similar soil conditions. Sixty-nine …


Integration Of Naturalistic Driving Characteristics Into Crash Forecasting Models, Nicholas Hart Jan 2016

Integration Of Naturalistic Driving Characteristics Into Crash Forecasting Models, Nicholas Hart

LSU Master's Theses

While highway safety has steadily improved throughout the United States, highway crashes and the resulting losses continue to be a significant concern in Louisiana. Louisiana consistently lags behind the country in many key areas of highway safety. To improve the conditions of roads in Louisiana, the Louisiana Department of Transportation and Development (LADOTD) has begun to implement the Highway Safety Manual (HSM) to evaluate existing and expected safety conditions and how to allocate limited improvement funds. However, as the HSM was developed using aggregated national statistics, it is not always able to reflect the conditions present on specific Louisiana roadways. …


Aerodynamic Mitigation Of Roof Suction Using Solar Panels, Laura M. Iverson Jan 2016

Aerodynamic Mitigation Of Roof Suction Using Solar Panels, Laura M. Iverson

LSU Master's Theses

This thesis aims to evaluate the feasibility of solar panels to be used as aerodynamic mitigation devices to reduce roof suction caused by high-speed winds on flat-roof, low-rise buildings. Roof suction is caused by negative pressures resulting in uplift on the roof, due to the wind passing over the sharp edges of the roof. Suction is a common cause of failure for these types of flat-roof, low-rise buildings during extreme wind events such as hurricanes, as the uplift force can cause the roof to separate from the building. A variety of mitigation devices have been proposed in the literature to …


The Design, Fabrication, And Validation Of A Film Cooled Rotating Turbine Cascade With An Actively Cooled Shroud In A Closed Loop Wind Tunnel, Christopher Michael Drewes Jan 2016

The Design, Fabrication, And Validation Of A Film Cooled Rotating Turbine Cascade With An Actively Cooled Shroud In A Closed Loop Wind Tunnel, Christopher Michael Drewes

LSU Master's Theses

To test shroud and blade cooling effectiveness, a closed loop, heated wind tunnel housing a film cooled rotating turbine cascade with prescribed blade and vane geometry surrounded by a fully cooled shroud with a leading edge gap were designed and assembled on Louisiana State University’s campus. Heat transfer coefficients and film cooling effectiveness results were computed using a 1-D semi-infinite solid conduction analysis of material temperatures obtained with liquid crystal thermography. Proper analysis required a step change in air temperature; so a bypass loop provided mainstream air heating while maintaining the shroud and blades at ambient temperature. Also, analysis required …


Numerical Modeling Of Wetland Hydrodynamics, Agnimitro Chakrabarti Jan 2016

Numerical Modeling Of Wetland Hydrodynamics, Agnimitro Chakrabarti

LSU Doctoral Dissertations

Wave induced erosion accounts for as much as 26% of landloss in coastal Louisiana. This dissertation work, focuses on answering research questions relevant to the design of two shoreline protection methods (a) vegetated wetlands and (b) nearshore breakwaters. Two types of numerical models are used - the three-dimensional (3D) Navier Stokes Equation for small to medium scale experiments and a depth integrated, fully non-linear Boussinesq model for dispersive waves for larger, field scale studies. The former model provides insights into the 3D hydrodynamics of wave interaction with vegetation canopies and breakwaters, while the latter model focuses on the horizontal two …


Automated Image Analysis And Spatial Computational Modeling Of Nf-Kb In Cerebrovascular Endothelial Cells, Kasey Catalfomo Jan 2016

Automated Image Analysis And Spatial Computational Modeling Of Nf-Kb In Cerebrovascular Endothelial Cells, Kasey Catalfomo

Theses and Dissertations

Cerebrovascular endothelial cells play a key part in the inflammatory response of the blood-brain barrier in pathological conditions such as Alzheimer’s disease. Specifically, the NF-κB signaling pathway plays a central role. Better understanding of the factors in inflammatory disease progression can lead to more effective treatments for such devastating illnesses like Alzheimer’s, asthma, arthritis, cancer, diabetes and many more inflammatory diseases. The proposed approach analyzes spatial NF-κB distribution contained in multispectral stacked micrograph images of cerebrovascular endothelial cells indexed based on dose of the activating protein and the length of activation. Image analysis code identifies the location of nuclear boundaries …


Characterization Of Human-Induced Vibrations, Benjamin Thomas Davis Jan 2016

Characterization Of Human-Induced Vibrations, Benjamin Thomas Davis

Theses and Dissertations

In the US alone, 20% of citizens will be over the age of 65 by the year 2030, and the largest challenge facing this growing demographic is not a new disease but a simple motion - the fall. These events are the premier cause of fatal and nonfatal injuries. In fact, a fall is so common that every 17 seconds an older adult is treated for fall-related injuries, and every 30 minutes, an older adult dies from fall complications. Research has shown a positive outcome of a fall event is largely dependent on the immediate response (<30 minutes) and rescue of the person.

This work explores …


Modeling Radionuclide Diffusion Using Moose A Multiscale, Multiphysics Platform, Jonathon Gardner Jan 2016

Modeling Radionuclide Diffusion Using Moose A Multiscale, Multiphysics Platform, Jonathon Gardner

Theses and Dissertations

Very durable ceramic waste forms have been proposed which offer longterm stability by binding certain radionuclides in their specific crystalline network. Moreover, multiple such ceramic phases can be tailored to contain specific radionuclides generated in the fuel cycle. Many such candidate ceramic forms are in the early stages of development with limited data. Modeling and simulation including modeling of diffusion can inform and provide direction to ongoing fabrication and experimental efforts. Material properties important in modeling can be obtained through laboratory measurement where available and atomistic simulation. Since diffusion occurs over multiple scales and follows multiple pathways, multiscale modeling is …


Detection Of Periodic Error And Structure Change Using Wavelet Analysis, Chao Lu Jan 2016

Detection Of Periodic Error And Structure Change Using Wavelet Analysis, Chao Lu

Theses and Dissertations

Heterodyne displacement measuring interferometry provides important metrology for applications requiring high resolution and accuracy. Heterodyne Michelson interferometers use a two-frequency laser source and separate the two optical frequencies into one fixed length and one variable length path via polarization. Ideally these two beams are linearly polarized and orthogonal so that only one frequency is directed toward each path. An interference signal is obtained by recombining the light from the two paths; this results in a measurement signal at the heterodyne (split) frequency of the laser source. This measurement signal is compared to the optical reference signal. Motion in the measurement …


Distributed Optimization And Control Of Islanded Microgrids, Md Rishad Hossain Jan 2016

Distributed Optimization And Control Of Islanded Microgrids, Md Rishad Hossain

Theses and Dissertations

A microgrid may have numerous multi-functional power electronic converters connecting sources, loads, and storage to the system. Systems where converters are the interface between many of the main sources of energy and load centers have the ability to direct the flow of energy if the control of the converters is coordinated. The influence of energy flow in a microgrid by coordinated action of converters is referred to here as ‘energy routing’. Energy routing allows for reduction of systems losses by optimizing source operating points and reducing transmission and distribution path losses. Energy ramp rates at various points in the system …


Development Of Novel High-Throughput Methodologies To Evaluate The Thermal Stability Of High-Temperature Thin-Film Crystals For Energy Applications, Jonathan Kenneth Bunn Jan 2016

Development Of Novel High-Throughput Methodologies To Evaluate The Thermal Stability Of High-Temperature Thin-Film Crystals For Energy Applications, Jonathan Kenneth Bunn

Theses and Dissertations

High temperature materials are used in a variety of energy applications such as jet turbines, high temperature sensors, and solid oxide fuel cells (SOFCs). Discovery of new materials and their optimization represents a difficult engineering challenge, as the materials have to be designed to have a high figure of merit during intense high temperature operations.

The large number of engineering considerations involved in the identification and optimization of such materials makes traditional one-by-one material investigations prohibitively time consuming. The time needed to explore large parameter domains can be significantly decreased through the use of high-throughput experimentation (HTE). HTE is an …


Investigation Of Heterogeneous Chemistry Of Pollutants In Flue Gas For Air And Oxy-Combustion, Benjamin D. Galloway Jan 2016

Investigation Of Heterogeneous Chemistry Of Pollutants In Flue Gas For Air And Oxy-Combustion, Benjamin D. Galloway

Theses and Dissertations

Due to increasing concerns associated with the emissions created from the combustion of coal, technologies are being modified or developed to limit many of these harmful emissions. The content of this thesis will focus on two technologies and the specific pollutants they seek to limit. The first investigated is selective catalytic reduction, which is utilized to decrease NO emissions. Due to the recent promulgation of the MATS regulations, focus has been on reducing the Hg emissions through the optimization of the SCR catalysts, making them bi-functional for NO reduction and Hg oxidation. The work presented here focuses on a novel …


Mechanistic-Empirical Pavement Design Guide (Mepdg) Method Implemented To Estimate Damage In Flexible And Rigid Pavements, Tenzin Gusto Jan 2016

Mechanistic-Empirical Pavement Design Guide (Mepdg) Method Implemented To Estimate Damage In Flexible And Rigid Pavements, Tenzin Gusto

Dissertations and Theses

The implementation of the Empirical-Mechanistic Pavement Design Guide (MEPDG) method for flexible and rigid pavements requires numerous input parameters. Most of these parameters can be easily determined while some require best estimates that are usually extracted from available literature. This thesis identifies the most critical input parameters in terms of their effects on the damage of pavements and their influence on the determination of the number of corrective maintenance cycles to be performed during the design life of pavements. It was found that for flexible pavement, change in the average monthly temperature by as little as results in large differences …


Improving Fairness In Peer-To-Peer Networks By Separating The Role Of Seeders In Network Infrastructures, Alireza Naghizadeh Jan 2016

Improving Fairness In Peer-To-Peer Networks By Separating The Role Of Seeders In Network Infrastructures, Alireza Naghizadeh

Turkish Journal of Electrical Engineering and Computer Sciences

No abstract provided.


Energy-Efficient And Environmentally Friendly Power Dispatch By Trigeneration With Renewable Energy And Energy Storage, Faisal Pazheri, Mohd Fauzi Othman, Nazar H. Malik, Abdulrehman Ali Al-Arainy Jan 2016

Energy-Efficient And Environmentally Friendly Power Dispatch By Trigeneration With Renewable Energy And Energy Storage, Faisal Pazheri, Mohd Fauzi Othman, Nazar H. Malik, Abdulrehman Ali Al-Arainy

Turkish Journal of Electrical Engineering and Computer Sciences

The importance of energy-efficient power generation that effectively utilizes the available fossil fuels is increasing due to the gradual decline in fossil fuel reserves. Furthermore, concern about global warming has led to rapid growth in renewable energy and energy storage technologies. This trend is encouraging power utilities to effectively exploit the use of renewable energy resources (RESs) and energy storage facilities (ESFs) for power supply systems. In this regards, trigeneration in the presence of RESs and ESFs can play an important role for efficient and clean power dispatch. This paper discusses the optimum power dispatch using a hybrid power plant …


Test 2145: John Deere 6135e, Nebraska Tractor Test Lab Jan 2016

Test 2145: John Deere 6135e, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Women In Science 2016, Clark Science Center's Summer Research Fellows Program Jan 2016

Women In Science 2016, Clark Science Center's Summer Research Fellows Program

SURF Abstracts (Women in Science)

Women in Science 2016 summarizes research done by Smith College’s Summer Research Fellowship (SURF) Program participants. Ever since its 1967 start, SURF has been a cornerstone of Smith’s science education. In 2016, 150 students participated in SURF (144 hosted on campus and nearby eld sites), supervised by 56 faculty mentor-advisors drawn from the Clark Science Center and connected to its eighteen science, mathematics, and engineering departments and programs and associated centers and units. At summer’s end, SURF participants were asked to summarize their research experiences for this publication.


Backward Dijkstra Algorithms For Finding The Departure Time Based On The Specified Arrival Time For Real-Life Time-Dependent Networks, Gelareh Bakhtyar, Vi Nguyen, Mecit Cetin, Duc Nguyen Jan 2016

Backward Dijkstra Algorithms For Finding The Departure Time Based On The Specified Arrival Time For Real-Life Time-Dependent Networks, Gelareh Bakhtyar, Vi Nguyen, Mecit Cetin, Duc Nguyen

Civil & Environmental Engineering Faculty Publications

A practical transportation problem for finding the “departure” time at “all source nodes” in order to arrive at “some destination nodes” at specified time for both FIFO (i.e., First In First Out) and Non-FIFO “Dynamic ” Networks is considered in this study. Although shortest path (SP) for dynamic networks have been studied/documented by various researchers, contributions from this present work consists of a sparse matrix storage scheme for efficiently storing large scale sparse network’s connectivity, a concept of Time Delay Factor (TDF) combining with a “general piece- wise linear function” to describe the link cost as a function of time …


Production Of Β-Silicon Carbide Nanofibers Using The Forcespinning® Method, Alfonso Salinas, Aleksey Altecor, Maricela Lizcano, Karen Lozano Jan 2016

Production Of Β-Silicon Carbide Nanofibers Using The Forcespinning® Method, Alfonso Salinas, Aleksey Altecor, Maricela Lizcano, Karen Lozano

Mechanical Engineering Faculty Publications

Silicon carbide (SiC) nanofibers were produced on a large scale using the Forcespinning® method. Non-oxide ceramics such as SiC are known for their low density, oxidation resistance, thermal stability, and wear resistance. The nanofibers were prepared using a solution-based method with polystyrene and polycarbomethylsilane as the precursor materials. Fiber spinning was performed under different parameters to obtain high yield, fiber homogeneity, and small diameters. The fibers were spun under a controlled nitrogen environment to prevent fiber oxidation. The resultant nonwoven nanofiber mats were then subjected to different heat treatments to evaluate the effect of these on the crystalline structure. Characterization …


Low Budget Forensic Drive Imaging Using Arm Based Single Board Computers, Eric Olson, Narasimha Shashidhar Jan 2016

Low Budget Forensic Drive Imaging Using Arm Based Single Board Computers, Eric Olson, Narasimha Shashidhar

Journal of Digital Forensics, Security and Law

Traditional forensic analysis of hard disks and external media typically involves a powered down machine and “dead analysis” of these devices. Forensic acquisition of hard drives and external media has traditionally been by one of several means: standalone forensic duplicator; using a hardware write-blocker or dock attached to a laptop, computer, workstation, etc., forensic operating systems that live boot from a USB, CD/DVD or virtual machines with preinstalled operating systems. Standalone forensics acquisition and imaging devices generally cost thousands of dollars. In this paper, we propose the use of single board computers as forensic imaging devices. Single board computers can …


In-The-Wild Residual Data Research And Privacy, William B. Glisson, Tim Storer, Andrew Blyth, George Grispos, Matt Campbell Jan 2016

In-The-Wild Residual Data Research And Privacy, William B. Glisson, Tim Storer, Andrew Blyth, George Grispos, Matt Campbell

Journal of Digital Forensics, Security and Law

As the world becomes increasingly dependent on technology, researchers in both industry and academia endeavor to understand how technology is used, the impact it has on everyday life, the artifact life-cycle and overall integrations of digital information. In doing so, researchers are increasingly gathering 'real-world' or 'in-the-wild' residual data, obtained from a variety of sources, without the explicit consent of the original owners. This data gathering raises significant concerns regarding privacy, ethics and legislation, as well as practical considerations concerning investigator training, data storage, overall security and data disposal. This research surveys recent studies of residual data gathered in-the-wild and …


Bytewise Approximate Matching: The Good, The Bad, And The Unknown, Vikram S. Harichandran, Frank Breitinger, Ibrahim Baggili Jan 2016

Bytewise Approximate Matching: The Good, The Bad, And The Unknown, Vikram S. Harichandran, Frank Breitinger, Ibrahim Baggili

Journal of Digital Forensics, Security and Law

Hash functions are established and well-known in digital forensics, where they are commonly used for proving integrity and file identification (i.e., hash all files on a seized device and compare the fingerprints against a reference database). However, with respect to the latter operation, an active adversary can easily overcome this approach because traditional hashes are designed to be sensitive to altering an input; output will significantly change if a single bit is flipped. Therefore, researchers developed approximate matching, which is a rather new, less prominent area but was conceived as a more robust counterpart to traditional hashing. Since the conception …


Security Analysis Of Mvhash-B Similarity Hashing, Donghoon Chang, Somitra Sanadhya, Monika Singh Jan 2016

Security Analysis Of Mvhash-B Similarity Hashing, Donghoon Chang, Somitra Sanadhya, Monika Singh

Journal of Digital Forensics, Security and Law

In the era of big data, the volume of digital data is increasing rapidly, causing new challenges for investigators to examine the same in a reasonable amount of time. A major requirement of modern forensic investigation is the ability to perform automatic filtering of correlated data, and thereby reducing and focusing the manual effort of the investigator. Approximate matching is a technique to find “closeness” between two digital artifacts. mvHash-B is a well-known approximate matching scheme used for finding similarity between two digital objects and produces a ‘score of similarity’ on a scale of 0 to 100. However, no security …


An Automated Approach For Digital Forensic Analysis Of Heterogeneous Big Data, Hussam Mohammed, Nathan Clarke, Fudong Li Jan 2016

An Automated Approach For Digital Forensic Analysis Of Heterogeneous Big Data, Hussam Mohammed, Nathan Clarke, Fudong Li

Journal of Digital Forensics, Security and Law

The major challenges with big data examination and analysis are volume, complex interdependence across content, and heterogeneity. The examination and analysis phases are considered essential to a digital forensics process. However, traditional techniques for the forensic investigation use one or more forensic tools to examine and analyse each resource. In addition, when multiple resources are included in one case, there is an inability to cross-correlate findings which often leads to inefficiencies in processing and identifying evidence. Furthermore, most current forensics tools cannot cope with large volumes of data. This paper develops a novel framework for digital forensic analysis of heterogeneous …


On Efficiency Of Distributed Password Recovery, Radek Hranický, Martin Holkovič, Petr Matoušek Jan 2016

On Efficiency Of Distributed Password Recovery, Radek Hranický, Martin Holkovič, Petr Matoušek

Journal of Digital Forensics, Security and Law

One of the major challenges in digital forensics today is data encryption. Due to the leaked information about unlawful sniffing, many users decided to protect their data by encryption. In case of criminal activities, forensic experts are challenged how to decipher suspect's data that are subject to investigation. A common method how to overcome password-based protection is a brute force password recovery using GPU-accelerated hardware. This approach seems to be expensive. This paper presents an alternative approach using task distribution based on BOINC platform. The cost, time and energy efficiency of this approach is discussed and compared to the GPU-based …


Towards Syntactic Approximate Matching - A Pre-Processing Experiment, Doowon Jeong, Frank Breitinger, Hari Kang, Sangjin Lee Jan 2016

Towards Syntactic Approximate Matching - A Pre-Processing Experiment, Doowon Jeong, Frank Breitinger, Hari Kang, Sangjin Lee

Journal of Digital Forensics, Security and Law

Over the past few years the popularity of approximate matching algorithms (a.k.a. fuzzy hashing) has increased. Especially within the area of bytewise approximate matching, several algorithms were published, tested and improved. It has been shown that these algorithms are powerful, however they are sometimes too precise for real world investigations. That is, even very small commonalities (e.g., in the header of a le) can cause a match. While this is a desired property, it may also lead to unwanted results. In this paper we show that by using simple pre-processing, we signicantly can in uence the outcome. Although our test …


An Investigation Of Inital Shock Cell Formation In Turbulent Coanda Wall Jets, Caroline P. Lubert, Christian R. Schwantes, Richard J. Shafer Jan 2016

An Investigation Of Inital Shock Cell Formation In Turbulent Coanda Wall Jets, Caroline P. Lubert, Christian R. Schwantes, Richard J. Shafer

Department of Mathematics and Statistics - Faculty Scholarship

Turbulent Coanda wall jets are present in a multitude of natural and man-made applications. Their obvious advantages in terms of flow deflection are often outweighed by disadvantages related to the increased noise levels associated with these jets. Primary high-frequency noise sources are turbulent mixing noise (TMN) and shock-associated noise (SAN). Clearly, accurate modeling of these noise sources will facilitate better predictions of the behavior of such jet noise with physical characteristics. This paper, which focuses on SAN, shows how the Method of Characteristics can be applied to a steady two-dimensional axisymmetric supersonic flow to rewrite the three governing partial differential …


Knee Internal Forces In Moderate Squat Exercise, Dumitru I. Caruntu, Jose Mario Salinas Jan 2016

Knee Internal Forces In Moderate Squat Exercise, Dumitru I. Caruntu, Jose Mario Salinas

Mechanical Engineering Faculty Publications

This paper deals with internal forces of human knee during moderate squat exercise. The moderate squat exercise consists of a descending phase from standing to the lowest position (largest flexion angle) in which no significant contact between thigh and calf occurs, and an ascending phase back to standing position. This research predicts the internal forces such as muscle forces, contact forces, and ligamentous forces. The ligamentous structures in this research consist of Anterior Cruciate Ligament (ACL), Posterior Cruciate Ligament (PCL), Lateral Collateral Ligament (LCL), and Medial Collateral Ligament (MCL). The ligaments are modeled as nonlinear elastic strips (they do not …


Evolution Of Moiré Profiles From Van Der Waals Superstructures Of Boron Nitride Nanosheets, Yunlong Liao, Wei Cao, John W. Connell, Zhongfang Chen, Yi Lin Jan 2016

Evolution Of Moiré Profiles From Van Der Waals Superstructures Of Boron Nitride Nanosheets, Yunlong Liao, Wei Cao, John W. Connell, Zhongfang Chen, Yi Lin

Applied Research Center Publications

Two-dimensional (2D) van der Waals (vdW) superstructures, or vdW solids, are formed by the precise restacking of 2D nanosheet lattices, which can lead to unique physical and electronic properties that are not available in the parent nanosheets. Moiré patterns formed by the crystalline mismatch between adjacent nanosheets are the most direct features for vdW superstructures under microscopic imaging. In this article, transmission electron microscopy (TEM) observation of hexagonal Moiré patterns with unusually large micrometer-sized lateral areas (up to similar to 1μm2 and periodicities (up to similar to 50 nm) from restacking of liquid exfoliated hexagonal boron nitride nanosheets (BNNSs) …