Open Access. Powered by Scholars. Published by Universities.®
- Keyword
-
- Cellulose (2)
- Finite Element Analysis (2)
- Regression analysis (2)
- Well control (2)
- 2195 (1)
-
- 2219 (1)
- ACT-R (1)
- APAS analysis (1)
- Actuator (1)
- Adiabatic effectiveness (1)
- Aeration (1)
- Aerodynamic loss (1)
- Aerodynamics (1)
- Age and skin (1)
- Air-lift (1)
- Al-2195 (1)
- Al-Li alloys (1)
- Alpha-tocopherol (1)
- Alzheimer's Disease (1)
- Amyloid (1)
- Anisotropy transformation (1)
- Ankle flexibility device (1)
- Ant colony optimization (1)
- ArcGIS (1)
- ArcHydro (1)
- Asynchronous multi-master replication (1)
- Automous healing (1)
- BASIC Stamp (1)
- BASINS (1)
- Bending Test (1)
Articles 1 - 30 of 59
Full-Text Articles in Entire DC Network
Intracellular Ice Formation In Adult Stem Cells In The Presence Of Polyvinyl Pyrrolidone, Avishek Guha
Intracellular Ice Formation In Adult Stem Cells In The Presence Of Polyvinyl Pyrrolidone, Avishek Guha
LSU Master's Theses
The main objective of this work was to assess the effect of 10% (w/v) polyvinylpyrrolidone (PVP) on the pattern of intracellular ice formation (IIF) in human adipose tissue derived adult stem cells (ASCs) in the absence of serum and other cryoprotective agents (CPAs). Passage 1 (P1) ASCs were cultured, washed and suspended in either 1x PBS (Phosphate Buffered Saline) or 10% w/v solution of PVP in 1x PBS. The freezing experiments were carried out using a fluorescence microscope equipped with a Linkam™ cooling stage using two different temperature/time cooling protocols. Both the cooling protocols had a common cooling ramp: cells …
Third Order Cmos Decimator Design For Sigma Delta Modulators, Hemalatha Mekala
Third Order Cmos Decimator Design For Sigma Delta Modulators, Hemalatha Mekala
LSU Master's Theses
A third order Cascaded Integrated Comb (CIC) filter has been designed in 0.5μm n-well CMOS process to interface with a second order oversampling sigma-delta ADC modulator. The modulator was designed earlier in 0.5μm technology. The CIC filter is designed to operate with 0 to 5V supply voltages. The modulator is operated with ±2.5V supply voltage and a fixed oversampling ratio of 64. The CIC filter designed includes integrator, differentiator blocks and a dedicated clock divider circuit, which divides the input clock by 64. The CIC filter is designed to work with an ADC that operates at a maximum oversampling clock …
Prioritization Of Safety Countermeasures For The State Of Louisiana Using Fuzzy Inference Systems, Meisam Akbarzadeh
Prioritization Of Safety Countermeasures For The State Of Louisiana Using Fuzzy Inference Systems, Meisam Akbarzadeh
LSU Master's Theses
In this study a fuzzy inference system is proposed for prioritization of countermeasures aimed at improving safety in the state of Louisiana. Countermeasures are prioritized based on their collective performance on cost, expected crash reduction and the severity of the problem they address. These three decision parameters can have six permutations in terms of their relative importance in decision making. In order to make the prioritization procedure handier for decision makers, the inference system is capable of being run under all six possible cases. Current safety standards influence the importance attached to crash reduction performance and severity of the problem …
Impact Of Watershed Delineation Detail On Hydrologic Process Modeling In Low Slope Areas, Jason Alexander Braud
Impact Of Watershed Delineation Detail On Hydrologic Process Modeling In Low Slope Areas, Jason Alexander Braud
LSU Master's Theses
Ascension Parish, located along the Mississippi River in southern Louisiana, is a low-lying, low slope landscape that primarily drains into the tidally-influenced Lake Maurepas. The predominant method of drainage within the parish is gravity drainage. Ascension Parish is currently one of the fastest growing areas in the United States. New developments have changed the area’s hydrology along with its landscape. Proper watershed delineation within the parish is critical for the management of and future improvements to the parish’s drainage infrastructure. Most of the recent drainage modeling in the parish has been performed using a light detection and ranging (LIDAR) digital …
The Development Of A Pore Pressure And Fracture Gradient Prediction Model For The Ewing Banks 910 Area In The Gulf Of Mexico, Jeffrey Steven Fooshee
The Development Of A Pore Pressure And Fracture Gradient Prediction Model For The Ewing Banks 910 Area In The Gulf Of Mexico, Jeffrey Steven Fooshee
LSU Master's Theses
The purpose of this project is to develop a pore pressure and fracture gradient prediction strategy for the Ewing Banks 910 (EW 910) area. Petrophysical and measured pressure data for eight wells previously drilled in the EW 910 area will be examined and reviewed. This strategy will help design future drilling and completion operations in the aforementioned area. Two pore pressure prediction strategies and one fracture gradient prediction strategy will be reviewed and applied to the available data. The first pore pressure prediction strategy reviewed was developed by W. R. Matthews. This strategy utilizes a geologic age specific overlay which …
A Decision Making Framework For Hurricane Evacuation And Sheltering, Jason Fennell
A Decision Making Framework For Hurricane Evacuation And Sheltering, Jason Fennell
LSU Master's Theses
There are few tools currently available to emergency managers to assist in making decisions about whether to evacuate, shelter locally, or shelter-in-place, and none of these tools explicitly consider risk to life safety. A methodology was developed to provide risk-based guidance for evacuation versus sheltering decision making. The hurricane hazards considered in the developed methodology are high winds, storm surge flooding and waves, and rainfall flooding. Vulnerability of buildings to these hazards and the associated risks to life safety are then determined. These results are compared to the hazards and risks associated with evacuation, particularly for medical special needs populations …
Asynchronous Replication Of Metadata Across Multi-Master Servers In Distributed Data Storage Systems, Ismail Akturk
Asynchronous Replication Of Metadata Across Multi-Master Servers In Distributed Data Storage Systems, Ismail Akturk
LSU Master's Theses
In recent years, scientific applications have become increasingly data intensive. The increase in the size of data generated by scientific applications necessitates collaboration and sharing data among the nation's education and research institutions. To address this, distributed storage systems spanning multiple institutions over wide area networks have been developed. One of the important features of distributed storage systems is providing global unified name space across all participating institutions, which enables easy data sharing without the knowledge of actual physical location of data. This feature depends on the ``location metadata'' of all data sets in the system being available to all …
Secure Distributed Detection In Wireless Sensor Networks Via Encryption Of Sensor Decisions, Venkata Sriram Siddhardh Nadendla
Secure Distributed Detection In Wireless Sensor Networks Via Encryption Of Sensor Decisions, Venkata Sriram Siddhardh Nadendla
LSU Master's Theses
We consider the problem of binary hypothesis testing using a distributed wireless sensor network. Identical binary quantizers are used on the sensor's observations and the outputs are encrypted using a probabilistic cipher. The third party (enemy) fusion centers are unaware of the presence of the probabilistic encipher. We find the optimal (minimum-probability-of-error) fusion rule for the ally (friendly) fusion center subject to a lower bound on the the probability of error for the third-party fusion centers. To obtain the minimum probability of error, we first prove the quasi-convexity of error probability with respect to the sensor's threshold for a given …
Numerical Investigation Of Film Cooling Fluid Flow And Heat Transfer Using Large Eddy Simulations, David Houston Leedom
Numerical Investigation Of Film Cooling Fluid Flow And Heat Transfer Using Large Eddy Simulations, David Houston Leedom
LSU Master's Theses
Large eddy simulations of film cooling from discrete holes inclined at 35° with a feeding plenum chamber are performed at a density ratio of 2 and blowing ratios from 0.5 to 2.0 in order to gauge the suitability and performance of different hole shapes. Cylindrical holes at length to diameter ratios of 1.75 and 3.5 as well as shaped holes (laterally diffused and console holes) at a length to diameter ratio of 3.5 are simulated issuing into a laminar crossflow at a Reynolds number of approximately 16,000 based on freestream velocity and hole diameter. The domain extends 15 hole diameters …
A Simulation-Based Evaluation Of Alternative Initial Responses To Gas Kicks During Managed Pressure Drilling Operations, Majid Davoudi
A Simulation-Based Evaluation Of Alternative Initial Responses To Gas Kicks During Managed Pressure Drilling Operations, Majid Davoudi
LSU Master's Theses
Managed pressure drilling (MPD) is an adaptation of conventional drilling that has been developed to manage and control subsurface pressures in the well in order to minimize specific drilling problems. The constant bottom hole pressure approach (CBHP) is a versatile method of MPD, where a closed annulus allows initial responses to kicks other than simply shutting in the well. The objective of this research was to identify and evaluate the best initial response to gas kicks taken during drilling as a basis for developing reliable well control procedures for CBHP operations. Nine non-circulating and circulating responses (NCRs and CRs) were …
Assessment Of Target Purity Difference For A Louisiana Sugar Mill, Luz Stella Polanco
Assessment Of Target Purity Difference For A Louisiana Sugar Mill, Luz Stella Polanco
LSU Master's Theses
The main goals of a “raw” sugarcane factory are to have an efficient profitable operation with the required sugar quality and maximum sugar recovery. The loss of sugar to final molasses accounts for 45 to 47% of the total sugar losses. An estimation of the average cost of the manufacturing losses for the 2007 harvest season was approximately $9 million – the sugar lost to the final molasses accounts for approximately 50% of this cost (Salassi, 2008). For final molasses, the “Target Purity” (or equilibrium purity) refers to the minimum level of sucrose that theoretically remains in solution for a …
Enhancing Reductive Dechlorination Of Chlorinated Ethenes And Ethanes In A Natural Treatment System, Caroline Burda
Enhancing Reductive Dechlorination Of Chlorinated Ethenes And Ethanes In A Natural Treatment System, Caroline Burda
LSU Master's Theses
Chlorinated solvent contamination continues to plague sites around the world. In many cases, lower chlorinated daughter products build up and remain in ground waters and soils. A Bio-Filter/Phytobed (BFP) system has been developed to replace a traditional pump and treat technology currently operating at the ReSolve Superfund site in North Dartmouth, MA. Pilot scale testing at the facility displayed a significant acclimation period prior to microbial dechlorination, as well as delayed degradation of chlorinated ethanes. Microcosm studies suggest that acidic conditions, possibly created by the peat mixture used to construct the bio-filter, inhibited bacterial growth. The neutralization of trench pH …
Numerical Modeling For Long Term Performance Of Soil-Bentonite Cut-Off Walls In Unsaturated Soil Zone, Sukanta Chakraborty
Numerical Modeling For Long Term Performance Of Soil-Bentonite Cut-Off Walls In Unsaturated Soil Zone, Sukanta Chakraborty
LSU Master's Theses
ABSTRACT The construction practices of containment walls are extremely important in this competitive economic market, but development is limited. Unsaturated zone is an integral part of the geotechnical problems, as it affects on any kind of soils structures. The unsaturated zone plays significant role in many aspects of water flow and contaminant transport, including containment system such as: cut-off walls, infiltration, soil moisture storage, evaporation, plant water uptake, ground water recharge, erosion, and runoff. This research focuses on the hydraulic sustainability and performance of soil-bentonite cutoff walls (Britton et al, 2004) models showing hydraulic behavior of barrier walls. The cutoff …
Dynamic Behavior Of Unsaturated Soils, Prathima Alla
Dynamic Behavior Of Unsaturated Soils, Prathima Alla
LSU Master's Theses
The behavior of unsaturated soils is different from the behavior of saturated soil deposits. Unsaturated soils have more than two phases; the pore water pressure in unsaturated soils is negative. The behavior of unsaturated soil when a dynamic loading such as an earthquake loading is imposed on them, the susceptibility of lab tested soils to liquefaction is investigated in this study. As the phenomenon of liquefaction occurs only in the case of saturated soil deposits, the behavior of unsaturated soil under these conditions is investigated. Sand and silty sand are used in this study, wetting and drying soil water characteristic …
Framework For Operability Assessment Of Production Facilities: An Application To A Primary Unit Of A Crude Oil Refinery, Sampath Yela
Framework For Operability Assessment Of Production Facilities: An Application To A Primary Unit Of A Crude Oil Refinery, Sampath Yela
LSU Master's Theses
This work focuses on the development of a methodology for the optimization, control and operability of both existing and new production facilities through an integrated environment of different technologies like process simulation, optimization and control systems. Such an integrated environment not only creates opportunities for op¬erational decision making but also serves as training tool for the novice engineers. It enables them to apply engineering expertise to solve challenges unique to the process industries in a safe and virtual environment and also assist them to get familiarize with the existing control systems and to understand the fundamentals of the plant operation. …
Two-Dimensional Microscanners With T-Shaped Hinges And Piezoelectric Actuators, Wenyu Song
Two-Dimensional Microscanners With T-Shaped Hinges And Piezoelectric Actuators, Wenyu Song
LSU Master's Theses
For a wide range of application areas such as medical instruments, defense, communication networks, industrial equipment, and consumer electronics, microscanners have been a vibrant research topic. Among various fabrication methodologies, MEMS (microelectromechanical system) stands out for its small size and fast response characteristics. In this thesis, piezoelectric actuation mechanism is selected because of its low voltage and low current properties compared with other mechanisms, which are especially important for the target application of biomedical imaging. Although 1- and 2-dimensional microscanners with piezoelectric actuators have been studied by several other groups, this thesis introduces innovative improvements in design of the piezoelectric …
Effects Of Physical And Mental Tasks On Heart Rate Variability, Satya Anasuya Paritala
Effects Of Physical And Mental Tasks On Heart Rate Variability, Satya Anasuya Paritala
LSU Master's Theses
Demands at work are associated with an increased risk of cardio vascular diseases, but little is known about its underlying connection. The purpose of this study was to evaluate the effects of physical and mental tasks that induced stress, on Heart Rate Variability (HRV). Another aim was to observe the trends in subjective workload ratings in conjunction with the physiological response of the heart and also to assess the comfort level of the participants while wearing the heart rate monitor and performing tasks. Heart rate was recorded while at rest and while performing the tasks. Subjective workload ratings were obtained …
Ternary To Binary Converter Design In Cmos Using Multiple Input Floating Gate Mosfets, Josephine Ratna Sathiaraj
Ternary To Binary Converter Design In Cmos Using Multiple Input Floating Gate Mosfets, Josephine Ratna Sathiaraj
LSU Master's Theses
In this work, a ternary to binary converter circuit is designed in 0.5μm n-well CMOS technology. The circuit takes two inputs corresponding to the ternary bits and gives four outputs, which are the binary equivalent bits of the ternary inputs. The ternary inputs range from (-1,-1)3 to (1,1) 3 which are decimal -4 to 4 and the four binary output bits are the sign bit (SB), most significant bit (MSB), second significant bit (SSB) and the least significant bit (LSB). The ternary inputs (-1, 0 and 1) are represented in terms of voltages of -3V, 0V and 3V. Multiple …
Mechanistic Foam Modeling And Simulations: Gas Injection During Surfactant-Alternating-Gas Processes Using Foam-Catastrophe Theory, Ali Afsharpoor
Mechanistic Foam Modeling And Simulations: Gas Injection During Surfactant-Alternating-Gas Processes Using Foam-Catastrophe Theory, Ali Afsharpoor
LSU Master's Theses
The use of foam for mobility control is a promising means to improve sweep efficiency in subsurface applications such as improved/enhanced oil recovery and aquifer remediation. Foam can be introduced into geological formations by injecting gas and surfactant solutions simultaneously or alternatively. Alternating gas and surfactant solutions, which is often referred to as surfactant-alternating-gas (SAG) process, is known to effectively create fine-textured strong foams due to fluctuation in capillary pressure. Recent studies show that foam rheology in porous media can be characterized by foam-catastrophe theory which exhibits three foam states (weak-foam, strong-foam, and intermediate states) and two strong-foam regimes (high-quality …
Biocompatible/ Bioresorbable Polymer Based Silver Nanaomaterial Coatng For Chronic Indwelling Medical Devices And Bioscaffolds For Tissue Regrowth, Ammar T. Qureshi
Biocompatible/ Bioresorbable Polymer Based Silver Nanaomaterial Coatng For Chronic Indwelling Medical Devices And Bioscaffolds For Tissue Regrowth, Ammar T. Qureshi
LSU Master's Theses
The objective of this study is to synthesize and characterize antimicrobial, bio-polymer based silver nanomaterials composite coatings, for use in chronic indwelling medical devices, and bioscaffolds. The coatings and bioscaffolds are comprised of novel biomass mediated silver nano particles (SNP) that are biocompatible, highly concentrated, highly pure, cost-effective, polydispersed and compatible with a range of polymer systems applicable for use with existing chronic indwelling medical devices. This thesis is divided into three main chapters. In Chapter 1, detailed review on the need for antimicrobial nanocomposite coatings for chronic indwelling medical devices along with different SNP synthesis and characterization methods is …
On The Effects Of Peripheral Sliding Velocity And Operating Differential Pressure In Rotary O-Ring Seals, Karan Lingerkar
On The Effects Of Peripheral Sliding Velocity And Operating Differential Pressure In Rotary O-Ring Seals, Karan Lingerkar
LSU Master's Theses
An O-ring seal is of paramount importance in hydraulic and pneumatic machinery used in oil and gas drilling processes. O-ring seals are generally employed to contain the environments of working fluids existing on either side of the seal from interacting with each other, to maintain a uniform pressure chamber and to eliminate the environmental contaminants that interact at the rubbing interface. Failure of dynamic O-rings in hydraulic and pneumatic machinery often results in considerable productivity loss to the chemical and petrochemical industries. Therefore, it is highly important to determine the life of an O-ring for these applications under various operating …
Neck Muscles Activity And Upper Body Extremity Angles In Dynamic Overhead Lifting, Mohamed Wassim Mokrani
Neck Muscles Activity And Upper Body Extremity Angles In Dynamic Overhead Lifting, Mohamed Wassim Mokrani
LSU Master's Theses
Injuries of the neck and shoulders are common among workers who perform overhead tasks. In order to develop an injury-free working environment with regards to occupational musculoskeletal stress, it is pivotal to understand the pathophysiology of mechanical stress on the musculoskeletal system. The objective of this research was to study the effect of overhead lifting on the sternocleidomastoid and upper Trapezius muscles. Upper body joint angles were also analyzed using APAS during the overhead lifting. This study was conducted using two devices. The set of equipment incorporates an electromyography device, and the APAS. Two electrodes were placed at the muscle …
Downhole Water Loop (Dwl) Well Completion For Water Coning Control --- Theoretical Analysis, Lu Jin
Downhole Water Loop (Dwl) Well Completion For Water Coning Control --- Theoretical Analysis, Lu Jin
LSU Master's Theses
The Thesis is an analytical and numerical analysis of a new method for completing and producing oil wells affected by water coning. The method enables producing oil with no or minimal water cut while keeping the water subsurface with downhole water loop (DWL) installation. Typically, a DWL well is triple-completed in the oil and water zones with the three completions separated by parkers. The top completion produces oil to the surface while the middle and bottom completions drain from and inject into the bottom water zone, respectively. Segregated-inflow operation of DWL well requires keeping the production and drainage-injection rates below …
Thermomechanical Characterization Of A Shape Memory Polymer Based Syntactic Foam, Damon Nettles
Thermomechanical Characterization Of A Shape Memory Polymer Based Syntactic Foam, Damon Nettles
LSU Master's Theses
Shape memory polymers (SMPs) are a type of smart material capable of “remembering” multiple shapes and transitioning between them in response to an external stimulus. They offer the potential to self-seal macro-length scale damage in a nearly autonomous fashion. Syntactic foams are lightweight structural materials currently used in the marine and aerospace industries. This study seeks to bring syntactic foams and SMPs together, retaining characteristics of both components, to create a low-density smart composite. The SMP based syntactic foam is used as the core of a grid stiffened sandwich structure capable of healing impact damage multiple times. In order to …
Fatigue Fracture And Microstructural Analysis Of Friction Stir Welded Butt Joints Of Aerospace Aluminum Alloys, Vinay Raghuram
Fatigue Fracture And Microstructural Analysis Of Friction Stir Welded Butt Joints Of Aerospace Aluminum Alloys, Vinay Raghuram
LSU Master's Theses
Friction-Stir-Welding (FSW) has been adopted as a major process for welding Aluminum aerospace structures. Al-2195, which is one of the new-generation Aluminum alloys that has been used on the external tank of the new super lightweight external tank of the space shuttle. The Lockheed Martin Space Systems (LMSS), Michoud Operations in New Orleans is continuously pursuing Friction-Stir-Welding technologies in its efforts to advance fabrication of the external tanks of the space shuttle. The future launch vehicles which will have to be reusable, m, an dates the structure to have good fatigue properties, which prompts an investigation into the fatigue behavior …
Bilateral Filter In Image Processing, Ming Zhang
Bilateral Filter In Image Processing, Ming Zhang
LSU Master's Theses
The bilateral filter is a nonlinear filter that does spatial averaging without smoothing edges. It has shown to be an effective image denoising technique. It also can be applied to the blocking artifacts reduction. An important issue with the application of the bilateral filter is the selection of the filter parameters, which affect the results significantly. Another research interest of bilateral filter is acceleration of the computation speed. There are three main contributions of this thesis. The first contribution is an empirical study of the optimal bilateral filter parameter selection in image denoising. I propose an extension of the bilateral …
Hearing Assessment Of Forest Loggers, Antonio A. Fonseca
Hearing Assessment Of Forest Loggers, Antonio A. Fonseca
LSU Master's Theses
Forest logging is the process in which trees are cut down for forest management and/or timber harvest. According to OSHA, logging is the most dangerous occupation in the United States. It consistently represents one of the most hazardous industries, with a fatality rate more than 21 times higher than the rate for all workers in the United States. Yet, little research has been performed to determine the long term effect of noise on forest loggers. OSHA regulations state that the maximum permissible hearing in an 8 hour shift should not exceed 90 dB. Occupational noise exposure is recognized as a …
Phosphorus Dynamics In The Marshland Upwelling System, Dhaval Shirish Shah
Phosphorus Dynamics In The Marshland Upwelling System, Dhaval Shirish Shah
LSU Master's Theses
The Marshland Upwelling System (MUS) is an alternative onsite wastewater treatment technology designed to utilize the natural ecology of saltwater marshes to remove human-borne contaminants. Previous research has assessed the ability of MUS to remove both total and orthophosphate. Studies have also indicated a clear zone of phosphorus (P) saturation occurring in MUS soils. Laboratory column study was performed to accomplish the objectives of this study which were to: 1) determine the fate and fractionation of phosphorus in the soil matrix, 2) understand sorption kinetics and determine phosphorus sorption potential of wetland soils in retaining phosphorus in the MUS, 3) …
Aerodynamic And Heat Transfer Studies In A Combustor-Fired, Fixed-Vane Cascade With Film Cooling, James William Post
Aerodynamic And Heat Transfer Studies In A Combustor-Fired, Fixed-Vane Cascade With Film Cooling, James William Post
LSU Master's Theses
Pressure and heat transfer data has been generated in a high-pressure, high-temperature vane cascade. This cascade differs from many others seen in typical low-pressure facilities using room temperature air. Primarily, a natural gas-fired combustor generates realistic turbulence profiles in the high-temperature exhaust gases that pass through the vane cascade. The fixed-vane cascade test sections have film cooling holes machined into the surfaces in arrangements that closely model configurations seen in real-life first-row nozzle guide vanes (NGV). Theoretical coolant jet-to-crossflow blowing ratios (M) range from 0.5 to 3.0. Coolant jet-to-crossflow theoretical density ratios (DR) used for typical tests vary between 1.0 …
Thermomechanical Modeling And Optimization Of Friction Stir Welding, Manthan Malde
Thermomechanical Modeling And Optimization Of Friction Stir Welding, Manthan Malde
LSU Master's Theses
This thesis research implemented an existing thermomechanical model of friction stir welding process, and studied the surrogate model-based optimization approach to obtain optimal process parameters for the modeled friction stir welding process. As an initial step, the thermomechanical model developed by Zhu and Chao for friction stir welding of 304L stainless steel was replicated using ANSYS. The developed model was then used to conduct parametric studies to understand the effect of various input parameters like total rate of heat input, welding speed and clamping location on temperature distribution and residual stress in the workpiece. With the data from the simulated …