Digital Commons Network^™

The Missouri Miner, February 07, 1996

The Missouri Miner Newspaper

No abstract provided.

Ccfss Technical Bulletin February 1996, Wei-Wen Yu Center For Cold-Formed Steel Structures

CCFSS Technical Bulletins (1993 - 2020)

No abstract provided.

The Multirate Simulation Of Facts Devices In Power System Dynamics, J. G. Chen, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, the multirate method is applied to the problem of simulating the dynamics of a power system which contains fast components such as induction machine loads and FACTS devices. Results concerning the numerical stability and accuracy of the multirate method are presented. Implementation concerns are also addressed by studying an example power system which contains a wide range of time response behavior

Nonlinear Lateral Pile Deflection Prediction In Sands, Shamsher Prakash, Sanjeev Kumar

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A method has been developed to predict the load-displacement relationship for single piles subjected to lateral load, embedded in sands, considering soil nonlinearity using subgrade reaction. This is the first systematic study to develop lateral load-deflection curves using modulus degradation with strain. Based on the analysis of 14 full-scale lateral pile-load tests, an empirical equation of modulus degradation with strain and a range of k hmax values, i.e., k h at 0.002 strain at 1 m (3.28 ft) depth, has also been proposed. An example problem is included to demonstrate its use. Based on this method, the computed load deflections …

Ccfss News February 1996, Wei-Wen Yu Center For Cold-Formed Steel Structures

CCFSS Newsletters (1999 - 2008)

No abstract provided.

The Missouri Miner, January 31, 1996

The Missouri Miner Newspaper

No abstract provided.

The Missouri Miner, January 24, 1996

The Missouri Miner Newspaper

No abstract provided.

The Missouri Miner, January 18, 1996

The Missouri Miner Newspaper

No abstract provided.

Examination Of The Origin, Variation, And Proper Use Of Expressions For The Estimation Of Association Constants By Capillary Electrophoresis, Kimber L. Rundlett, Daniel W. Armstrong

Chemistry Faculty Research & Creative Works

Over the last several decades a variety of techniques have been developed to determine apparent equilibrium constants for molecular association in solution (e.g., to micelles, proteins, cyclodextrins, antibiotics, etc.). The relationships describing binding isotherms appear in several forms and have been given several different names. It is well known that most of these expressions are closely related and that some may be more advantageous than others for experimental or statistical reasons. In the case of electrophoresis, association constants are calculated from the relationship between ligand concentration and the measured electrophoretic mobility of the solute. This relationship has appeared in many …

Missouri S&T Magazine, Spring 1996, Miner Alumni Association

Missouri S&T Magazine

No abstract provided.

Applications Of The Upside-Down Normal Loss Function, David Drain, A. M. Gough

Mathematics and Statistics Faculty Research & Creative Works

The upside-down normal loss function (UDNLF) is a weighted loss function that has accurately modeled losses in a product engineering context. The function''s scale parameter can be adjusted to account for the actual percentage of material failing to work at specification limits. Use of the function along with process history allows the prediction of expected loss-the average loss one would expect over a long period of stable process operation. Theory has been developed for the multivariate loss function (MUDNLF), which can be applied to optimize a process with many parameters-a situation in which engineering intuition is often ineffective. Computational formulae …

Asymptotic Analysis Of Oseen Equations For Small Viscosity, R. Temam, X. Wang

Mathematics and Statistics Faculty Research & Creative Works

In this article, we derive explicit asymptotic formulas for the solutions of Oseen's equations in space dimension two in a channel at large Reynolds number (small viscosity ε). These formulas exhibit typical boundary layers behaviors. Suitable correctors are defined to resolve the boundary obstacle and obtain convergence results valid up to the boundary. We study also the behavior of the boundary layer when simultaneously time and the Reynolds number tend to infinity in which case the boundary layer tends to pervade the whole domain.

Inverse Limits On [0,1] Using Logistic Bonding Maps, Marcy Barge, William Thomas Ingram

Mathematics and Statistics Faculty Research & Creative Works

In this paper we investigate inverse limits on [0,1] using a single bonding map chosen from the logistic family, fλ (x) = 4λx(1-x) for 0 ≤ λ ≤ 1. Many interesting continua occur as such inverse limits from arcs to indecomposable continua. Among other things we observe that up through the Feigenbaum limit the inverse limit is a point or is hereditarily decomposable and otherwise the inverse limit contains an indecomposable continuum. © 1996 Elsevier Science B.V. All rights reserved.

Effect Of Pt Doping On Nucleation And Crystallization In Li2o · 2sio2 Glass: Experimental Measurements And Computer Modeling, K. Lakshmi Narayan, K. F. Kelton, C. S. Ray

Materials Science and Engineering Faculty Research & Creative Works

Heterogeneous nucleation and its effects on the crystallization of lithium disilicate glass containing small amounts of Pt are investigated. Measurements of the nucleation frequencies and induction times with and without Pt are shown to be consistent with predictions based on the classical nucleation theory. A realistic computer model for the transformation is presented. Computed differential thermal analysis data (such as crystallization rates as a function of time and temperature) are shown to be in good agreement with experimental results. This modeling provides a new, more quantitative method for analyzing calorimetric data.

Plastic Fiber Rolling For Concrete Reinforcement, Jeffery S. Thomas

Masters Theses

"Fiber reinforced concrete is gaining in acceptance and usage as its strength and toughness benefits are realized. Polypropylene fibers are currently the most commonly used fibers. However, the cost of virgin plastics limits the percent content that can be economically added to concrete. One would first believe that recycled plastics could offer a viable alternative to virgin-plastic fibers, but at present time extra selection and cleaning steps required to reprocess the recycled plastic into fibers makes it more expensive than virgin-plastic fibers. A fiber rolling process conceived and developed at the University of Missouri-Rolla has the potential of making recycled …

An Approach To Just-In-Time Implementation In Discrete Parts Manufacturing, Phillip Gregory Shirey

Masters Theses

"Just-In-Time manufacturing is a philosophy that encourages waste reduction and the elimination of non-value-added activities. The processes affected include office and shop personnel. When successfully implemented, JIT accounts for improved production lead time cycles, reduced inventories, improved employee morale, reduced cost of goods, and continuous improvements of the total business process.

This thesis identifies real world problems many medium size U.S. manufacturing companies now face, and an approach to JIT implementation in discrete parts manufacturing. The approach includes developing strategies to motivate the employees and to implement the tools and techniques of JIT, Total Quality Management, ISO 9001, and MRP …

Segmental Motion Of Surface-Bound Swollen Poly(Methyl Acrylate)-D, Minghua Liang

Masters Theses

"Poly (methyl acrylate)-d_a (PMA-d_a) was prepared and adsorbed on silica then swollen with toluene and carbon tetrachloride. Comparisons of deuterium NMR spin-lattice relaxation time, T₁, and spin-spin relaxation time, T₂, for the adsorbed polymer at different temperatures were made to obtain information about the backbone motion of the surface-bound polymer. The results suggest that the local fast motions may be similar to those in the corresponding solution, but the longer-range molecular motions were more restricted than those in solution. The log-normal distribution yielded mean correlation times which were 4-10 times slower for the …

Ultrasonically Initiated Free Radical Catalyzed Emulsion Polymerization Of Methyl Methacrylate, H. C. Joe Chou

Doctoral Dissertations

"The emulsion polymerization of methyl methacrylate initiated by ultrasound has been studied at ambient temperature using sodium lauryl sulfate as the surfactant.

The source of the free radical for the initiation process was found to come from the degradation of the sodium lauryl sulfate presumably in aqueous phase. The weight average molecular weight (Mw) of the poly (methyl methacrylate) obtained varied from 2,500,000 to 3,500,000 g mole^-1 and the conversion for the polymerization was up to 70%.

The polymerization rate, the number of polymer particles generated and the free radical concentration in initiation process were found to increase with …

Method And Apparatus For Applying Herbicides, Marian Mazurkiewicz

Mining Engineering Faculty Research & Creative Works

A method of applying herbicide to plants involves delivering a liquid herbicide solution to the plant foliage in a high pressure jet of sufficient energy to physically disrupt the surface of the foliage. The high pressure jet can be either a coherent jet or it can be a stream of droplets. The coherent stream can have sufficient energy to cut the foliage, creating new surfaces that are more wettable by the herbicide solution, and more susceptible to penetration by the herbicide in the solution. The droplets in the droplet stream can be made to be of sufficient size and energy …

Optimization For Maximum Performance High-Speed Engines, David W. Riggins

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Fuel-air combustion and the generation of irreversibility in high-speed flows are described in terms of the fundamental principles of nonequilibrium, work availability, and entropy increases. Engine thrust is analytically related to the overall engine irreversibility and the degree of combustion: Issues involving mixing enhancement assessment and engine optimization are then formalized and clarified. The concept of thrust-potential, as used in engine design and optimization, is shown to be a consistent application of the principles and findings of this and related investigations. This work was supported through NASA Grant NAG 1-1189. Special thanks are due to Charles McClinton at NASA Langley …

Hamiltonian Based Adaptive Critics For Missile Guidance, S. N. Balakrishnan, Jie Shen

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A Hamiltonian based adaptive critic structure is proposed for solving missile guidance problems. This structure consists of a supervisor neural network called 'critic' and a controller network called 'action'. Together they are used to solve model-based guidance problems. The advantage of this approach is that: i) the training data for each network is created by the other network, ii) the converged solutions yield near optimal guidance over the entire span of the training range, and iii) they can be used as feedback controllers though trained off-line. A main contribution is that we establish a direct link between traditional optimal control …

Heat Transfer In Two-Phase Solid-Rocket Plumes, Harlan F. Nelson, John C. Fields

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Results of a direct simulation Monte Carlo (DSMC) and free molecule (FM) analysis of convective heat transfer to Al2O3 particles in solid-rocket plume environments are presented. The particle diameters are assumed to be 4μm, and the plume gases are CO2, H2O, CO, and N2. The plume gas temperature is 2000 K. Particle temperatures of 1500, 2000, and 2500 K are investigated for Knudsen numbers from 1/2 to 1000 (from slip flow to FM flow). The Nusselt number is presented in terms of Knudsen number and Reynolds number (or relative velocity). Both the Kavanau and the Kashmarov and Svirshevskii correlations generally …

Global Characteristics And Structure Of Hydrogen-Air Counterflow Diffusion Flames, J. Zhao, Kakkattukuzhy M. Isaac, G. L. Pellett

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A model based on similarity transformation, for the nitrogen-diluted, H2-air opposed-jet laminar counterflow diffusion flame (CFDF), was developed independently of earlier models, and numerically solved to study flame location and flame structure and extinction limits. Numerical stiffness is handled by a special treatment of the species production term. Flame location with respect to the stagnation plane is identified as an important parameter that governs H2-air diffusion flames, and physical explanations are given to show how flame location is affected by fuel dilution, strain rate, and Lewis number. Results show very good agreement with experimental extinction conditions. The effect of thermal …

Analysis Of A Single-Phase Induction Machine With A Shifted Auxiliary Winding, T. A. Walls, Scott D. Sudhoff

Electrical and Computer Engineering Faculty Research & Creative Works

This paper extents the method of multiple reference frames to the analysis of asymmetrical induction motors with non-orthogonal stator windings, with particular emphasis on the permanent split capacitor (PSC) machine. The predictions of the method are verified by comparison to both experimental results and to results obtained using a machine variable computer simulation. Once verified, the method is used to derive the transfer function relating rotor speed to load torque disturbance, which is of particular interest when analyzing PSC machines driving compressor loads. It is shown that the transfer function exhibits a distinct resonant point, and that the magnitude of …

An Experimentally Obtainable Heat Source Due To Absorption Of Ultrasound In Biological Media, James L. Drewniak, F. Dunn

Electrical and Computer Engineering Faculty Research & Creative Works

Deposition of heat as a result of loss in an ultrasonic wave may result in damage to biological tissues. The extensive use of ultrasound for diagnostic purposes during pregnancy necessitates the evaluation of thermal risk to a developing fetus during routine clinical exposures. Because of the small ultrasonic absorption coefficient in soft tissues at low megahertz frequencies, temperature elevations exceeding 1 °C are not expected from clinically employed ultrasound systems, and there is no evidence that such small temperature increases can result in deleterious effects. However, when the propagation path includes bone, which is known to be highly lossy, theoretical …

Transient And Dynamic Average-Value Modeling Of Synchronous Machine Fed Load-Commutated Converters, Keith Corzine, S. D. Sudhoff, H. J. Hegner, D. E. Delisle

Electrical and Computer Engineering Faculty Research & Creative Works

A new average-value model of a synchronous machine fed load-commutated converter is set forth in which the stator dynamics are combined with the DC link dynamics. This model is shown to he extremely accurate in predicting system transients and in predicting frequency-domain characteristics such as the impedance looking into the synchronous machine fed load-commutated converter. The model is verified against a detailed computer simulation and against a hardware test system, thus providing a three-way comparison. The proposed model is shown to be much more accurate than models in which the stator dynamics are neglected

Two Methods Of Neural Network Controlled Dynamic Channel Allocation For Mobile Radio Systems, Kelvin T. Erickson, Edward J. Wilmes

Electrical and Computer Engineering Faculty Research & Creative Works

Two methods of dynamic channel allocation using neural networks are investigated. Both methods continuously optimize the mobile network based on changes in calling traffic. The first method uses backpropagation model predictions to aid the channel allocator. Each cell contains a backpropagation model which provides the channel allocator a call traffic prediction allowing the channel allocator to effectively optimize the network. The second method uses the same backpropagation models along with actor-critic models to perform the channel allocation. The actor-critics learn to model traffic activity between adjacent cells in real-time, and thereby learn to allocate channels dynamically between cells. The learning …

Programmable Logic Controllers, Kelvin T. Erickson

Electrical and Computer Engineering Faculty Research & Creative Works

Programmable logic controllers (PLCs) are at the forefront of manufacturing automation. Many factories use programmable logic controllers to cut production costs and/or increase quality. PLCs and their unique language, ladder logic, are the workhorses of factory automation. Higher-level languages, such as sequential function charts and function blocks, ease the programming task for large systems. However, ladder logic remains the dominant language at present

Dynamically Regularized Fast Rls With Application To Echo Cancellation, Steven L. Grant

Electrical and Computer Engineering Faculty Research & Creative Works

This paper introduces a dynamically regularized fast recursive least squares (DR-FRLS) adaptive filtering algorithm. Numerically stabilized FRLS algorithms exhibit reliable and fast convergence with low complexity even when the excitation signal is highly self-correlated. FRLS still suffers from instability, however, when the condition number of the implicit excitation sample covariance matrix is very high. DR-FRLS, overcomes this problem with a regularization process which only increases the computational complexity by 50%. The benefits of regularization include: (1) the ability to use small forgetting factors resulting in improved tracking ability and (2) better convergence over the standard regularization technique of noise injection. …

Fault Classification Using Kohonen Feature Mapping, Badrul H. Chowdhury, Kunyu Wang

Electrical and Computer Engineering Faculty Research & Creative Works

Applications of neural networks to power system fault diagnosis have provided positive results and shown advantages in process speed over conventional approaches. This paper describes the application of a Kohonen neural network to fault detection and classification using the fundamental components of currents and voltages. The Electromagnetic Transients Program is used to obtain fault patterns for the training and testing of neural networks. Accurate classifications are obtained for all types of possible short circuit faults on test systems representing high voltage transmission lines. Short training time makes the Kohonen network suitable for on-line power system fault diagnosis. The method introduced …