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Full-Text Articles in Architecture
Predictive Relationships For Uptake Of Organic Contaminants By Hybrid Poplar Trees, Joel Gerard Burken, Jerald L. Schnoor
Predictive Relationships For Uptake Of Organic Contaminants By Hybrid Poplar Trees, Joel Gerard Burken, Jerald L. Schnoor
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
Twelve Organic Compounds Commonly Found at Hazardous Waste Sites Were Studied for Uptake by Hybrid Poplar Trees. the Vegetative Uptake of Many of These Compounds Has Not Previously Been Demonstrated for Plant Species Being Utilized for Phytoremediation, Such as Hybrid Poplar Trees. Experiments Were Conducted Hydroponically Utilizing 14C-Labeled Compounds to Ascertain Translocation and Fate. Predictive Relationships for the Translocation and Partitioning to Plant Tissues Were Developed from the Experimental Data. Translocation and Partitioning Relationships based on Compounds' Octanol- Water Partitioning Coefficients (100 K(Ow)) Produced the Best Results, But the Relationships Did Not Allow for Fully Accurate Prediction of Each Contaminant's …
Optimum Control Of A Hybrid System For Seismic Excitations With State Observer Technique, Franklin Y. Cheng, Hongping Jiang
Optimum Control Of A Hybrid System For Seismic Excitations With State Observer Technique, Franklin Y. Cheng, Hongping Jiang
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
This paper presents a theoretical study of a hybrid seismic response control system comprising a passive fluid viscous damper and an active control system with a hydraulic actuator and acceleration sensors. The analytical model of this system is derived in the discrete time domain with actuator and clamper dynamics considered. Based on digital control theory, a state observer is established for optimal control strategies of the hybrid system. This study shows that the hybrid system gains the advantages of both active and passive control techniques currently in vogue; and that, with the state observer technique, a seismic response control system …
Natural Treatment And On-Site Processes, Kevin D. White, Joel Gerard Burken
Natural Treatment And On-Site Processes, Kevin D. White, Joel Gerard Burken
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
No abstract provided.
Biological Fixed-Film Systems, Mark W. Fitch, Natalie Pearson, Gene Richards, Joel Gerard Burken
Biological Fixed-Film Systems, Mark W. Fitch, Natalie Pearson, Gene Richards, Joel Gerard Burken
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
No abstract provided.
Gaseous Cah Removal By Biofiltration In Presence And Absence Of A Nonionic Surfactant, J. O. Kim, Purush K. Terkonda, S. D. Lee
Gaseous Cah Removal By Biofiltration In Presence And Absence Of A Nonionic Surfactant, J. O. Kim, Purush K. Terkonda, S. D. Lee
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
The objectives of this study were to investigate the biodegradation of gaseous trichloroethylene (TCE) and tetrachloroethylene (PCE) in an activated carbon biofilter inoculated with phenol-oxidizing microorganisms and to study the effect of surfactant concentration below its critical micelle concentration (CMC) on the removal efficiency of TCE or PCE. For the enhanced biofiltration, a biodegradable nonionic surfactant was added to biofilters. The investigation was conducted using two specially built stainless steel biofilters, one for TCE and the other for PCE. The removal efficiency of gaseous TCE was 100% at a residence time of 7 min and its average inlet concentration of …
Evaluation Of Toxicity, Bioavailability And Speciation Of Lead, Zinc And Cadmium In Mine/Mill Wastewaters, Mujde Erten-Unal, Bobby G. Wixson, Nord L. Gale, Jerry L. Pitt
Evaluation Of Toxicity, Bioavailability And Speciation Of Lead, Zinc And Cadmium In Mine/Mill Wastewaters, Mujde Erten-Unal, Bobby G. Wixson, Nord L. Gale, Jerry L. Pitt
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
The toxicity of common compounds of lead, cadmium and zinc was evaluated in waters similar to that found in the world's largest lead producing area in Missouri. Static, acute toxicity tests were performed using fathead minnows (Pimephales promelas) and water fleas (Daphnia magna) respectively. Test organisms were subjected to varying amounts of sulfide, carbonate, chloride and sulfate salts of lead, zinc and cadmium mixed in hard, alkaline waters typical to this region. Median lethal concentrations were calculated using nominal versus measured metal concentrations. Measured metal concentrations included four different metal fractionation (extraction/filtration) techniques at different pH levels which included "dissolved", …
Optimizing Multiagent, Multi-Injected Swell Modifier, Marshall B. Addison, Thomas M. Petry
Optimizing Multiagent, Multi-Injected Swell Modifier, Marshall B. Addison, Thomas M. Petry
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
Interactions of expansive clay soils with transportation facilities have caused billions of dollars of damage. In the process of determining agents and methodologies to overcome expansive clay behavior, multiple injections of chemical agents into the subgrade to modify clay behavior are most promising. A study was conducted to optimize a potassium-rich solution of four parts. The modifying solution has been injected into expansive clay subgrades with success since the early 1970s. A laboratory methodology was developed to inject specimens multiple times and to conduct swell tests. Screening tests were conducted to evaluate linear effects that each of the four constituents …
Hybrid Control Of Seismic Structures With Optimal Placement Of Control Devices, Franklin Y. Cheng, Hongping Jiang
Hybrid Control Of Seismic Structures With Optimal Placement Of Control Devices, Franklin Y. Cheng, Hongping Jiang
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
A theoretical study is carried out for optimal controller placement and effectiveness of a hybrid seismic response control system comprising a viscous fluid damper and a servovalve-controlled hydraulic actuator. A stochastic seismic response of controlled structures is first investigated with nonorthogonal damping and stiffness; then a statistical method for optimal placement of control devices on seismic-resistant structures is developed. With such placement, a hybrid system can achieve greater performance in that much less control force is required to reduce structural seismic response to a given level. This study also shows the hybrid system is superior to both active and passive …
Recent Research And Developments In Cold-Formed Steel Framing, Roger A. Laboube, Wei Wen Yu
Recent Research And Developments In Cold-Formed Steel Framing, Roger A. Laboube, Wei Wen Yu
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
Recent research studies at the University of Missouri-Rolla (UMR) have focused on developing a better understanding of the behavior of cold-formed steel members and truss assemblies. This research was initiated by the more widespread use of cold-formed steel in the residential construction market, and the need to provide structurally reliable, as well as highly economical design solutions. Steel trusses are commonly assembled using C-shaped sections and self-drilling screws. Based on UMR findings, appropriate design recommendations have been proposed for the web and chord members of a truss. Also of concern is the introduction of large holes in the webs of …
The Structural Behavior Of Homogeneous And Hybrid Stub Columns Under Dynamic Loading Conditions, Chi Ling Pan, Wei Wen Yu
The Structural Behavior Of Homogeneous And Hybrid Stub Columns Under Dynamic Loading Conditions, Chi Ling Pan, Wei Wen Yu
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
It has been recognized that the mechanical properties of sheet steels and the structural strength of cold-formed steel members can be influenced by strain rate. For studying the local and postbuckling behavior of the stiffened and unstiffened compression elements under dynamic loading condition, 97 stub columns which were assembled from the same material have been tested under different strain rates. In order to study the structural behavior of hybrid cold-formed stub columns, a total of 144 specimens were investigated. In addition, 52 drop silo tests of stub columns were conducted at General Motors Corporation (GM). The results showed that the …
Multiple Objective Structural Optimization With Genetic Algorithm And Fuzzy Logic, Franklin Y. Cheng, Dan Li, Jeffrey J.F. Ger
Multiple Objective Structural Optimization With Genetic Algorithm And Fuzzy Logic, Franklin Y. Cheng, Dan Li, Jeffrey J.F. Ger
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
This paper presents a constrained multiobjecthe optimzation method in the form of a robust, practical, problem-independent algorithm, and investigates the effect of multiobjective optimization on structural design. The study includes properties and characteristics of multiobjective optimization and solutions. Design objectives, constraints, and design variables as well as their effect on structural design and behavior are investigated. Fuzzy set theory is also included to construct a fuzzy constrained environment. Two new genetic algorithm operators — multiobjective fitness function and niche method -- are proposed. A new genetic algorithm process, Pareto set filter, is added to genetic algorithms. A 10-story setback building …
Genetic Algorithm Development For Multiobjective Optimization Of Structures, Franklin Y. Cheng, Dan Li
Genetic Algorithm Development For Multiobjective Optimization Of Structures, Franklin Y. Cheng, Dan Li
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
Genetic algorithms (GAs) have the characteristic of maintaing a population of solutions and can search in a parallel manner for many nondominated solutions. These features coincide with the requirement of seeking a Pareto optimal set in a multiobjective (multicriteria, vector) optimization problem. The retionale for multiobjective optimization via GAs is that at each generation, the fitness of each individual is defined according to its nondominated property. Because nondominated individuals are assigned the highest fitness values, the convergence of a population will go th the nondominated zone: the Pareto optimal set. Based on this concept, a Pareto, GA, whose goal is …
Contribution Of Externally Bonded Frp To Shear Capacity Of Rc Flexural Members, Ahmed Khalifa, William J. Gold, Antonio Nanni, M. I. Abdel Aziz
Contribution Of Externally Bonded Frp To Shear Capacity Of Rc Flexural Members, Ahmed Khalifa, William J. Gold, Antonio Nanni, M. I. Abdel Aziz
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
Fiber reinforced polymer (FRP) materials are continuing to show great promise for use in strengthening reinforced concrete structures. These materials are an excellent option for use as external reinforcing because of their light weight, resistance to corrosion, and high strength. Externally bonded FRP sheets have been used to increase moment capacity of flexural members and to improve confinement in compression members. Investigations into the use of externally bonded FRP sheets for shear strengthening have also been conducted and have been shown to be viable. The objectives of this study were to review the current research on shear strengthening with FRP …