Engineering Commons^™

Interaction Between Millimeter Oscillations And Monocrystal Hexagonal Ferrites With Modulated Resonance Frequency, Alexander A. Kitaytsev, Marina Koledintseva

Electrical and Computer Engineering Faculty Research & Creative Works

Investigation of non-linear stable effects taking place at ferromagnetic resonance (FMR) in monocrystal arbitrarily oriented hexagonal ferrite resonators (HFR) with controlled (modulated) resonance frequency is an urgent problem. The presented analysis is based on two approaches: the “quasistatic” approach using the static tensor of the HFR magnetic susceptibility and the “dynamic” one based on the solution of the magnetization vector motion equation (MVME) with varying time coefficients due to modulated magnetization field or HFR angle of orientation. The first approach is valid at low modulation frequencies (in comparison with the relaxation frequency of the HFR) and the second one can …

Phytoremediation: Plant Uptake Of Atrazine And Role Of Root Exudates, Joel G. (Gerard) Burken, Jerald L. Schnoor

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Phytoremediation is an Emerging Technology for Degradation of Organic Chemicals. the Potential of Phytoremediation in the Cleanup of Contaminated Sites and Prevention of Non-Point-Source Pollution Was Examined with the Pesticide Atrazine in Two Experimental Systems. Uptake Was Determined in Batch Experiments with 14C Ring-Labeled Atrazine and Hybrid Poplar Trees Grown in Two Soil Types. Mineralization Was Studied Utilizing Soil Microcosms with the Addition of Root Exudates. Results Indicate that Poplar Cuttings Were Able to Uptake the Majority of Applied Atrazine that Was Not Tightly Sorbed to the Organic Fraction of the Soil, with No Detectable Adverse Effects to the Trees. …

On Seismic Displacements Of Rigid Retaining Walls, Yingwei Wu, Shamsher Prakash

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Rigid retaining walls experience both sliding and rocking displacement during earthquakes. Richards and Elms' (1979) method incorporates only sliding displacements in design. A realistic method of computing both sliding and rocking displacements of the walls based on nonlinear soil properties both for the base soil and backfill was developed by Rafnsson and Prakash (1994). A design procedure based on this method was then developed by Prakash. et al (1995, b). Comparisons of the displacements of typical walls by both the methods have been made. Also, typical field data from recent earthquakes has been analyzed to compare the observed displacements with …

Behavior Of Low Ductility Steels In Cold-Formed Steel Connections, S. Seleim, Roger A. Laboube

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Accepted design approaches for the strength of a steel connection rely on adequate ductility of the connected parts. In cold-formed steel connection design, adequate ductility is defined by the Specification for the Design of Cold-Formed Steel Members. To assess the influence of low ductility steels, i.e. steels not meeting the specification ductility requirements, single lap bolted connections were studied. The experimental study reflected key connection strength parameters: edge distance, sheet thickness, sheet width, bolt pattern, Fu/Fy, and percentage elongation. Test results indicate that failure modes in low ductility steels are inconsistent with observed failure modes in adequate ductility steels. It …

Performance Of Laminated Glass Units Under Simulated Windborne Debris Impacts, Richard A. Behr, Paul A. Kremer

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Severe windstorm events such as Hurricane Andrew in 1992 have underscored the vulnerability of building envelopes to breaching under the combined effects of windborne debris impacts and wind pressures. Damage to building interiors and disruption of building functions are exacerbated greatly when building envelopes are breached. When the inner glass ply in a laminated glass window unit is unbroken, the integrity of that part of the building envelope is preserved - provided that the inner glass ply has sufficient resistance to subsequent positive and negative wind pressures. In an effort to develop glazing systems that are resistant to breaching due …

Biodegradation Of Nonionic Surfactants And Effects Of Oxidative Pretreatment, Craig D. Adams, S. Spitzer, R. M. Cowan

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The aerobic biodegradability of nonionic, ethoxylated surfactants and model compounds, and the effect of advanced oxidation pretreatment on the biodegradability of the biorefractory surfactants were examined. Bioassays conducted using a mixed microbial seed showed that the linear primary alcohol ethoxylates, the fatty acid ethoxylates, and also polyethylene glycol were all degradable. The biomineralization of the linear secondary alcohol ethoxylate, ethylene oxide/propylene oxide block copolymer, and alkylphenol ethoxylate was observed to be inhibited to varying degrees. Additional bioassays were conducted on model compounds to examine the effect of specific structural components on biodegradability. Advanced oxidation pretreatment using hydrogen peroxide in combination …

Multiobjective Optimization Of Structures With And Without Control, Franklin Y. Cheng, Dan Li

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A multiobjective optimization algorithm is introduced, and the effect of different objective functions on structural design is investigated. The basic idea of this approach is to support the decisionmaker by directly selecting the best compromise solution from the Pareto optimal solutions. A payoff matrix is first constructed by optimizing each objective function subject to the given constraints; a substitute function is then formed. Under the original constraint conditions, maximizing the substitute function gives the best compromise solution. This research shows that multiobjective optimization should be carried out to obtain a rational structural design. Two structural optimal design examples - one …

Comparison Of Linear And Nonlinear Seismic Drift Histories For Midrise Steel Frames, K. Z. Truman, C. Pantelides, Richard A. Behr, Abdeldjelil Belarbi

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The linear and nonlinear seismic responses for two midrise office buildings of five- and 24-storeys were generated by two independent research groups using three commercial analysis packages, ABAQUS, SAP90 and DRAIN-2DX. The results indicate that a variability of up to 25% occurred between the independent research groups' seismic responses. Originally, these models and analyses were generated for the purpose of aiding in the development of load histories for the seismic testing of architectural glass at the University of Missouri-Rolla. The independent researchers were provided with the same structures, accelerograms and basic modelling assumptions and were directed to perform both linear …

Effects Of Accelerated Weathering On Architectural Laminated Glass In A Windstorm Environment, Richard A. Behr, Joseph E. Minor, Paul A. Kremer

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

An experimental study was conducted to assess the serviceability and ultimate limit state behavior of a fully glazed architectural laminated glass system under accelerated weathering conditions. Glazed specimens included heat-strengthened laminated glass with a low-emissivity, metallic solar coating on one glass surface next to the polyvinyl butyral interlayer. The laminated glass units were anchored to the aluminum curtain wall frame with a perimeter anchor bead of medium-modulus structural silicone sealant. Accelerated weathering was performed in a manner similar to the provisions of ASTM E773-88 and E774-92. All specimens (weathered and unweathered) were then subjected to a severe windstorm simulation test, …

Bending And Shear Behavior Of Web Elements With Openings, M. Y. Shan, Roger A. Laboube, Wei-Wen Yu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Cold-formed steel C-sections are frequently used as wall studs and floor joists in both commercial and residential construction. To facilitate installation of ancillary systems such as electrical wiring and plumbing, the C-section is manufactured with a web opening. Although the opening offers construction advantages, it may degrade the structural integrity of the member. To quantify the degrading effect of a web opening, a study has been conducted at the University of Missouri-Rolla (UMR). The UMR study included the loading conditions of bending, shear, web crippling, and the combinations thereof. This paper summarizes the results of an experimental study which addressed …

Seismic Test Methods For Architectural Glazing Systems, Richard A. Behr, Abdeldjelil Belarbi

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

An ongoing effort is being made at the University of Missouri-Rolla to develop standard laboratory test methods and codified design procedures for architectural glass under seismic loadings. Recent laboratory work has yielded some promising results regarding the development of an appropriate seismic test method for architectural glass, as well as identifying ultimate limit states that quantify the seismic performance and damage thresholds of various glass types. Specifically, a straightforward "crescendo-like" in-plane dynamic racking test, performed at a constant frequency, has been employed successfully. Two ultimate limit states for architectural glass have been defined: (1) a lower ultimate limit state corresponding …

A Class Of Modified Hopfield Networks For Aircraft Identification And Control, Jie Shen, S. N. Balakrishnan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This paper presents a class of modified Hopfield neural networks and their use in solving aircraft optimal control and identification problems. This class of networks consists of parallel recurrent networks which have variable dimensions that can be changed to fit the problems under consideration. It has a structure to implement an inverse transformation that is essential for embedding optimal control gain sequences. Equilibrium solutions are discussed. Energy minimization of the networks leads to identification of the system parameters. Numerical results are provided to identify the dynamics of an aircraft, and the corresponding optimal control is calculated online. Comparison of the …

Target Profile Estimation Using Haar Functions, William R. Bockman, S. N. Balakrishnan, Christopher D'Souza, James Cloutier

Mechanical and Aerospace Engineering Faculty Research & Creative Works

An approach to estimating the target acceleration in a maneuvering target model using Haar function partial summations to model the target acceleration is developed. A kinematic constraint is applied to the maneuvering target model and the effects of the use of this constraint are reviewed.

Kentucky Traffic Accident Facts 1996 Report, Kentucky Transportation Center, Kentucky State Police

Kentucky Transportation Center Research Report

KENTUCKY’S TRAFFIC ACCIDENT FACTS report for 1996 is based on accident reports submitted to the Accident Unit housed in the Kentucky State Police Information Services Branch, Records Section. As required by Kentucky Revised statutes 189.635, “every law enforcement agency whose officers investigate a vehicle accident of which a report must be made...shall file a report of the accident...within ten days after investigation of the accident upon forms supplied by the bureau.” The stated purpose of this requirement is to utilize date on traffic accidents” for such purposes as will improve the traffic safety program in the Commonwealth.” Data contained in …

A Hybrid Observer For High Performance Brushless Dc Motor Drives, Keith Corzine, S. D. Sudhoff

Electrical and Computer Engineering Faculty Research & Creative Works

Brushless DC motor drive systems are used in a wide variety of applications. These drives may be classified as being one of two types: sinusoidal drives in which there are no low-frequency harmonics in the current waveforms and no low-frequency torque ripple; and nonsinusoidal drives in which there is considerable low-frequency harmonic content, both in the current and torque waveforms. Although sinusoidal drives feature superior performance, they are generally more expensive since rotor position must be sensed on a continuous basis, thus requiring an optical encoder or a resolver, whereas relatively inexpensive Hall-effect sensors may be used for nonsinusoidal drives. …

Degradation Of Trichloroethylene By Methanol-Grown Cultures Of Methylosinus Trichosporium Ob3b Pp358, Mark W. Fitch, G. E. Speitel, G. Georgiou

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A Soluble Methane Monooxygenase-Constitutive Mutant Strain of Methylosinus Trichosporium OB3b, Strain PP358, Was Grown with Methanol as the Carbon Source, and the Kinetics of Trichloroethylene (TCE) Degradation Were Determined. PP358 Exhibited High TCE Degradation Rates under Both Oxygen- and Carbon-Limiting Conditions. the Optimal Pseudo First-Order Rate Constant for TCE Was Comparable to the Values Measured for Cells Grown with Methane. We Found that Growth under Oxygen-Limiting Conditions Results in Increased Accumulation of Polyhydroxybutyrate, Which in Turn Correlates with Higher Transformation Capacities for TCE. It Was Also Shown that Methanol Inhibits TCE Degradation Only at High Concentrations. Thus, Methanol-Grown Cultures of …

Compliant Pliers, Ashok Midha, S. C. Visser

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The pliers include an endless loop, a top jaw appended to the endless loop, and a bottom jaw appended to the endless loop. The endless loop includes in series a top grip handle, a spring segment, a bottom grip handle and a compliant strip interconnecting the top and bottom grip handles. A rolling surface on the top grip handle rolls on a contact portion of the bottom grip handle. The rolling action causes the compliant strip to flex which causes the top and bottom jaws to move toward one another. The endless loop provides a built-in automatic spring and enhances …

Input Dimension Reduction In Neural Network Training-Case Study In Transient Stability Assessment Of Large Systems, S. Muknahallipatna, Badrul H. Chowdhury

Electrical and Computer Engineering Faculty Research & Creative Works

The problem in modeling large systems by artificial neural networks (ANN) is that the size of the input vector can become excessively large. This condition can potentially increase the likelihood of convergence problems for the training algorithm adopted. Besides, the memory requirement and the processing time also increase. This paper addresses the issue of ANN input dimension reduction. Two different methods are discussed and compared for efficiency and accuracy when applied to transient stability assessment.

1996 Highway Cost Allocation Update: Technical Report, John A. Deacon, Jerry G. Pigman

Kentucky Transportation Center Research Report

This update of the highway cost allocation study is the seventh in a recent series begun in the early 1980's by the Kentucky Transportation Cabinet and the Kentucky Transportation Center. The primary objectives were to determine the level of revenue contribution and cost responsibility for each class of highway user. The base year of the study is FY 1995; the most recent time period for which revenue and cost data were available. Highway use or travel activity data for calendar year 1994 was the most recent available. A basic premise of the study was that only state maintained highways were …

1996 Highway Cost Allocation Update: Overview And Summary, John A. Deacon, Jerry G. Pigman

Kentucky Transportation Center Research Report

No abstract provided.

A Dual Neural Network Architecture For Linear And Nonlinear Control Of Inverted Pendulum On A Cart, S. N. Balakrishnan, Victor Biega

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The use of a self-contained dual neural network architecture for the solution of nonlinear optimal control problems is investigated in this study. The network structure solves the dynamic programming equations in stages and at the convergence, one network provides the optimal control and the second network provides a fault tolerance to the control system. We detail the steps in design and solve a linearized and a nonlinear, unstable, four-dimensional inverted pendulum on a cart problem. Numerical results are presented and compared with linearized optimal control. Unlike the previously published neural network solutions, this methodology does not need any external training, …

Treatability Of S-Triazine Herbicide Metabolites Using Powdered Activated Carbon, Craig D. Adams, Tammy L. Watson

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Widespread use of s-triazine herbicides such as atrazine, simazine, and cyanazine has led to the contamination of many ground-water and surface-water supplies with the parent compounds as well as by primary metabolites (e.g., deethylatrazine, deisopropylatrazine, and deethylcyanazine). Ozonation has been shown to produce many of the same byproducts. Activated carbon adsorption has been designated by the U.S. Environmental Protection Agency as the best available technology (BAT) for the treatment of herbicides in drinking water. Little data is available, however, on the applicability of activated carbon treatment for the control of the primary degradation products of herbicides. In this study, the …

Computer Simulations Versus Real Experiments In A Portable Structural Mechanics Laboratory, Richard A. Behr

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Efforts are being made to develop practical and effective innovations for undergraduate engineering teaching laboratories. The 'ANEX' process, in which computer simulations are compared in nearly real time with physical measurements made on bench-scale model experiments, is now being used successfully in an introductory structural analysis course. ANEX is described, as well as current plans to develop software simulation modules and matched, bench-scale model experiments for new 'MECH-ANEX' laboratory applications in lower-division statics and mechanics of materials courses. The ANEX process could also be adapted to undergraduate laboratory applications in a wider range of engineering and science disciplines.

Bs News

Building Services Engineering

No abstract provided.

Automatic Pcb Inspection Algorithms: A Survey, Madhav Moganti, Fikret Ercal, Cihan H. Dagli, Shou Tsunekawa

Computer Science Faculty Research & Creative Works

The importance of the inspection process has been magnified by the requirements of the modern manufacturing environment. In electronics mass-production manufacturing facilities, an attempt is often made to achieve 100% quality assurance of all parts, subassemblies, and finished goods. A variety of approaches for automated visual inspection of printed circuits have been reported over the past two decades. In this survey, algorithms and techniques for the automated inspection of printed circuit boards are examined. A classification tree for these algorithms is presented and the algorithms are grouped according to this classification. This survey concentrates mainly on image analysis and fault …

Consensus Building Model To Select Casis In Small Communities, Steven W. Mccrary, Colin Othniel Benjamin, Vijay E. Ambavanekar

Engineering Management and Systems Engineering Faculty Research & Creative Works

This paper examines: (1) The automated mapping/facilities management and geographic information system (AM/FM/GIS), which are called computer-assisted spatial information systems (CASIS) in this paper, software selection process; (2) develops a knowledge-based, multiattribute, multiobjective, consensus building model (CBM); and (3) establishes the validity for using the exogenously developed CBM for the selection of CASIS software. Model formulation is based on analyzing how well the attributes of the software meet user requirements in four areas: functionality, technical capability, vendor characteristics, and costs. Expert knowledge was gathered from several domain practitioners regarding the ability of GIS software functions to fulfill a user's needs. …

Stock Market Prediction Using Different Neural Network Classification Architectures, Karsten Schierholt, Cihan H. Dagli

Engineering Management and Systems Engineering Faculty Research & Creative Works

In recent years, many attempts have been made to predict the behavior of bonds, currencies, stocks, or stock markets. The Standard and Poors 500 Index is modeled using different neural network classification architectures. Most previous experiments used multilayer perceptrons for stock market forecasting. A multilayer perceptron architecture and a probabilistic neural network are used to predict the incline, decline, or steadiness of the index. The results of trading with the advice given by the network is then compared with the maximum possible performance and the performance of the index. Results show that both networks can be trained to perform better …

Maintenance Conditions And Occupant Behavior In Government Provided Housing In Lagos, Nigeria, Paul Abayomi Bajere

Dissertations and Theses @ UNI

Maintenance conditions and occupant behavior towards maintenance in government housing in developing countries are universal problems. Perceptions, construction technology, competencies, tenureship, cultural tradition, and demographic factors have been identified as major constraints influencing housing maintenance behavior. There was a need for this study because limited literature exists on maintenance of urban government provided housing in Nigeria. Also, the degree of success of the government's efforts concerning environmental cleaning has not been remarkable.

The primary purpose of this study was to investigate the maintenance of government provided housing, as perceived by the residents and observed by the researcher, to determine the …

Conversion Of Coal Tar To Soot During Coal Pyrolysis In A Post-Flame Environment, Thomas H. Fletcher, Jinliang Ma, Brent W. Webb

Faculty Publications

Coal pyrolysis experiments were performed in the postflame region of a CH4/H2/air flat-flame burner operating under fuel-rich conditions, where the temperature and gas compositions were similar to those in the near-burner region of a large-scale coal-fired furnace. Volatiles released from the coal particles formed a cloud of soot particles at high temperatures in the absence of oxygen. The soot particles in the cloud were collected at different residence times using a water-cooled, nitrogen-quenched suction probe. Test variables included the reaction temperature and coal type. Soot yields in terms of weight percentage of dry ash-free coal were measured based on bulk …

Randomized Approximation Of The Constraint Satisfaction Problem, Hoong Chuin Lau, Osamu Watanabe

Research Collection School Of Computing and Information Systems

We consider the Weighted Constraint Satisfaction Problem (W-CSP) which is a fundamental problem in Artificial Intelligence and a generalization of important combinatorial problems such as MAX CUT and MAX SAT. In this paper, we prove non-approximability properties of W-CSP and give improved approximations of W-CSP via randomized rounding of linear programming and semidefinite programming relaxations. Our algorithms are simple to implement and experiments show that they are run-time efficient.