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- Commonsense knowledge (2)
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Articles 1 - 11 of 11
Full-Text Articles in Engineering Science and Materials
Optimizing Light Requirements And Dilution Rates For Maximizing Algal Cell Growth And Lipid Content For Biofuel Feedstock Production, Beatrice Gabriela Terigar
Optimizing Light Requirements And Dilution Rates For Maximizing Algal Cell Growth And Lipid Content For Biofuel Feedstock Production, Beatrice Gabriela Terigar
LSU Doctoral Dissertations
There is a rapidly growing interest in the potential of microalgae as feedstock for the next generation of biofuels. The current study was designed to meet the following objectives: (1) Investigate the interdependence among cell density, biomass and lipid productivity to maximize feedstock production from outdoor cultures; (2) Investigate the effect of cycling high-intensity lights to identify optimum Dark:Light (D/L) ratios, which can be effectively used by researchers to maximize aerial biomass productivities; (3) Develop a deterministic model to simulate the biomass productivity in an continuous-flow bioreactor at various hydraulic retention times. Results indicated that variation in HRTs has a …
Resolving Pronominal Anaphora Using Commonsense Knowledge, Seyedeh Leili Javadpour
Resolving Pronominal Anaphora Using Commonsense Knowledge, Seyedeh Leili Javadpour
LSU Doctoral Dissertations
Coreference resolution is the task of resolving all expressions in a text that refer to the same entity. Such expressions are often used in writing and speech as shortcuts to avoid repetition. The most frequent form of coreference is the anaphor. To resolve anaphora not only grammatical and syntactical strategies are required, but also semantic approaches should be taken into consideration. This dissertation presents a framework for automatically resolving pronominal anaphora by integrating recent findings from the field of linguistics with new semantic features. Commonsense knowledge is the routine knowledge people have of the everyday world. Because such knowledge is …
Optimal Consignment Stocking Policies For A Supply Chain Under Different System Constraints, Hui Zhi Yi
Optimal Consignment Stocking Policies For A Supply Chain Under Different System Constraints, Hui Zhi Yi
LSU Doctoral Dissertations
The research aims are to enable the decision maker of an integrated vendor-buyer system under Consignment Stock (CS) policy to make the optimal/sub-optimal production/replenishment decisions when some general and realistic critical factors are considered. In the system, the vendor produces one product at a finite rate and ships the outputs by a number of equal-sized lots within a production cycle. Under a long-term CS agreement, the vendor maintains a certain inventory level at the buyer’s warehouse, and the buyer compensates the vendor only for the consumed products. The holding cost consists of a storage component and a financial component. Moreover, …
Quantification Of The Environmental Impact Of Titanium Dioxide Photocatalytic Pavements For Air Pollution Remediation, Heather Lee Dylla
Quantification Of The Environmental Impact Of Titanium Dioxide Photocatalytic Pavements For Air Pollution Remediation, Heather Lee Dylla
LSU Doctoral Dissertations
Photocatalytic concrete pavements are a promising technology for mobile source air pollution remediation, however before widespread application of this technology is realized many unanswered questions remain regarding its overall environmental impact. In response to these questions, the goal of this study was to increase the understanding of the environmental impact of photocatalytic concrete pavement highways. To achieve this goal, the objectives of this study were to (A) construct a model that evaluates the nitrogen oxides (NOx) reduction from photocatalytic pavements, (B) quantify the nitrates released from the photocatalytic degradation of NOx, and (C) identify and characterize pathways for TiO2 nanoparticle …
Automated Semantic Content Extraction From Images, Mahdi Arab Khazaeli
Automated Semantic Content Extraction From Images, Mahdi Arab Khazaeli
LSU Doctoral Dissertations
In this study, an automatic semantic segmentation and object recognition methodology is implemented which bridges the semantic gap between low level features of image content and high level conceptual meaning. Semantically understanding an image is essential in modeling autonomous robots, targeting customers in marketing or reverse engineering of building information modeling in the construction industry. To achieve an understanding of a room from a single image we proposed a new object recognition framework which has four major components: segmentation, scene detection, conceptual cueing and object recognition. The new segmentation methodology developed in this research extends Felzenswalb's cost function to include …
Geodatabase-Assisted Storm Surge Modeling, Sait Ahmet Binselam
Geodatabase-Assisted Storm Surge Modeling, Sait Ahmet Binselam
LSU Doctoral Dissertations
Tropical cyclone-generated storm surge frequently causes catastrophic damage in communities along the Gulf of Mexico. The prediction of landfalling or hypothetical storm surge magnitudes in U.S. Gulf Coast regions remains problematic, in part, because of the dearth of historic event parameter data, including accurate records of storm surge magnitude (elevation) at locations along the coast from hurricanes. While detailed historical records exist that describe hurricane tracks, these data have rarely been correlated with the resulting storm surge, limiting our ability to make statistical inferences, which are needed to fully understand the vulnerability of the U.S. Gulf Coast to hurricane-induced storm …
A Metaheuristic-Based Simulation Optimization Framework For Supply Chain Inventory Management Under Uncertainty, Qinglin Duan
A Metaheuristic-Based Simulation Optimization Framework For Supply Chain Inventory Management Under Uncertainty, Qinglin Duan
LSU Doctoral Dissertations
The need for inventory control models for practical real-world applications is growing with the global expansion of supply chains. The widely used traditional optimization procedures usually require an explicit mathematical model formulated based on some assumptions. The validity of such models and approaches for real world applications depend greatly upon whether the assumptions made match closely with the reality. The use of meta-heuristics, as opposed to a traditional method, does not require such assumptions and has allowed more realistic modeling of the inventory control system and its solution. In this dissertation, a metaheuristic-based simulation optimization framework is developed for supply …
The Investigation Of Valve Operators' Torque Production Capabilities And Optimal Handwheel Height, Angle, And Opening Technique, Saif K. Al-Qaisi
The Investigation Of Valve Operators' Torque Production Capabilities And Optimal Handwheel Height, Angle, And Opening Technique, Saif K. Al-Qaisi
LSU Doctoral Dissertations
This research consists of two projects concerned with handwheel-valve operations. The objectives of poject-1 were to: (1) introduce an ergonomically-modified valve-wrench and compare it to conventional valve-opening methods, in terms of efficiency (time to open valve), perceived physical exertion (Borg-scale), and muscle loading of shoulder and trunk muscles; and (2) determine whether the torque setting (15 Nm and 30 Nm) of the valve affects the preferred valve-opening method. Four methods were evaluated, including using bare hands (BH), conventional wrench-restricted (CW-R, assumes presence of obstructions), conventional wrench-unrestricted (CW-U, assumes no obstructions), and modified wrench (MW). Electromyography (EMG) activities were measured from …
Microstructure And Physics-Based Structural Models For Suspended Clay-Exopolymer Flocs, Xiaoling Tan
Microstructure And Physics-Based Structural Models For Suspended Clay-Exopolymer Flocs, Xiaoling Tan
LSU Doctoral Dissertations
Costal or shoreline waters are often characterized by high concentrations of suspended cohesive sediments (or clay) affected by varied organic matters (mostly extracellular polymeric substances or exopolymers), salt, and hydrodynamic disturbance. Resulting from the flocculation-disaggregation between the colloidal clay and exopolymer, the size and structure changes of the cohesive sediments are of key importance for understanding sediment transport processes (i.e., settling, breakage, and survivability) and the geotechnical and geophysical properties of the bottom bed. Because the coastal environment is extremely complicated, with many unpredictable and uncontrollable parameters, current knowledge is still insufficient to predict or fully explain the behavior of …
Silver Nanoparticles As Drug Delivery Systems, Ammar Tahseen Qureshi
Silver Nanoparticles As Drug Delivery Systems, Ammar Tahseen Qureshi
LSU Doctoral Dissertations
The goal of this project is to study the potential applications of silver nanoparticles (SNPs) in the medical device and pharmaceutical industries. Bone cements have been used in the orthopedic surgeries for many years to anchor prosthetics while filling up the spaces between the prostheses and bone. Antibiotics are an active component of bone cements but the increasing bacterial resistance to these antibiotics and difficulty of shaping and molding the bone cements increases the need for new antimicrobial biomaterials. Adult stem cell based regenerative therapies have been one of the most widely researched areas of tissue engineering. This is due …
Designing A Cost Effective Microalgae Harvesting Strategy For Biodiesel Production With Electrocoagulation And Dissolved Air Flotation, Adam James Dassey
Designing A Cost Effective Microalgae Harvesting Strategy For Biodiesel Production With Electrocoagulation And Dissolved Air Flotation, Adam James Dassey
LSU Doctoral Dissertations
Microalgal harvesting strategies for biodiesel production have been a major setback in the industry with high energy estimates of $3400/ton biomass by centrifugation. The present study utilized effective mass and energy balances to reduce these large operating costs. The energy for Stage 1 centrifugation was reduced by 82% when harvesting 28.5% of biomass at 18 L/min as opposed to 95% harvesting at 1 L/min. This strategy was further confirmed using electrocoagulation (EC) with Nannochloris and Dunaliella algae with perforated aluminum and iron electrodes at low (< 6 mg/L) metal ion concentrations. Despite 20% lower harvesting efficiencies, the iron electrodes were more energy and cost efficient with operating costs less than $0.03/L oil when flocculating and settling Nannochloris and Dunaliella cultures. Furthermore, a continuous multistage algae harvester using EC and dissolved air flotation (DAF) for Stage 1 harvesting and centrifugation for Stage 2 dewatering was designed. It was determined throughout the testing that greater EC costs for improved harvesting efficiencies were necessary to offset the large energy requirements of the DAF. The multistage system dewatered a low density (100 mg/L) Nannochloris to 20% solids for a final energy requirement of 1.536 kWh/kg algae ($138/ton). Using the data collected from this research and existing literature, a life cycle analysis was assembled to judge the sustainability of microalgal biofuels in Louisiana. High and low energy estimates for culturing (mixing, CO2, nutrients), harvesting, lipid extraction and energy conversion were compared with the current research. Scaling the EC/DAF system for a full size facility was expected to reduce the harvesting costs to 1.133 kWh/kg algae, resulting as $0.44/L oil for a culture with 20% lipids. Despite this improvement in harvesting costs, the production of algal for the sole purpose of biodiesel was not economically viable. Considering a system with a growth rate of 15 g/m2/day and lipid content of 20%, the energy inputs exceeded the outputs from biodiesel production by 36% under the most ideal conditions. However, incorporating additional revenue through wastewater treatment and biogas production from residual biomass could improve sustainability and profitability of algal biodiesel to an 18.5% energy surplus at its current state.