Engineering Commons^™

Method And Apparatus For Sensing The Regeneration Of A Diesel Engine Particulate Trap, John H. Johnson, Peter V. Woon

Michigan Tech Patents

A diesel engine exhaust system is provided with a particulate trap for collecting the products of incomplete combustion during the engine power cycle. A sensing mechanism including an electrode downstream of the trap and a signal generating circuit provides a positive indication of occurrence of regeneration of the trap. Charged particles generated during regeneration induce a charge of the electrode, that charge activates the signal generating circuit and it, in turn, produces an indication external of the exhaust system that trap regeneration is occurring. That indication can be in the operator’s compartment.

Control Of Vortical Separation On A Circular Cone, Nikos J. Mourtos

Faculty Publications

For conical bodies, at moderate angles of attack, the flow separates from the lee side, forming two vortices. Although the vortex lift contrihution is highly desirable, as the angle of attack increases, the vortex system becomes asymmetric, and eventually the vortices breakdown. Thus, some control of the separation process is necessary if the vortex lift is to be exploited at higher angles of attack. The theoretical model which is used in this analysis has three parts. First, the 'single line-vortex' model is used within the framework of 'slender-body theory' to compute the outer inviscid field for specified separation lines. Second, …

Santa Clara Magazine, Volume 32 Number 4, Summer 1990, Santa Clara University

Santa Clara Magazine

10 - WHAT'S UP WITH COMIC BOOKS? Comic books aren't what they used to be but they continue to charm our children. By Mitch Finley '73

14 - STRESS, ILLNESS, AND PSYCHOTHERAPY The meaning of a stressful situation determines whether it is perceived as a challenge to be overcome or a demoralization. By Jerome D. Frank

18 - A BEELINE TO THE USA "Killer" bees have been winging their way from Brazil since scores of queens escaped a Sao Paolo lab in 1957. By Paul M. McCarthy '46

21 - PROMISE & OPPORTUNITY An economic forecast for the 1990s by …

Research Project Summaries (July 1989-December 1990), Utah Water Research Laboratory

Reports

From every side we hear of new threats to our water supply. Carcinogens, droughts, dam failures, global warming, hazardous wastes, deforestation, overpopulation, liability, and an aging infrastructure become household fears; this list grows longer and more foreboding to the average citizen. Some of these threats are real, while others are imaginary. Some we know how to overcome and others we can find ways to overcome, yet, for some, we are still helpless. The strength of a university lies in its success in stimulating inquisitive minds in critical examination of the problems of the world. People sense hope as experts find …

Impulse, Kara Donohue

Impulse (Jerome J. Lohr College of Engineering Publication)

Features:
[Page 2] Sander named engineering dean
[Page 3] Students create model of proposed laboratory
[Page 4] Kurtenbach named Distinguished Engineer
[Page 5] Governor creates Buckley award
[Page 5] Merit service award named for Buckley
[Page 5] Structural seminar draws many speakers

Special Section: Entrepreneurship:
[Page 6] Governor's proclamation
[Page 7-9] Entrepreneurs' Workshop offers training for successful business ventures
[Page 9] A letter from President Robert Wagner
[Page 10] Jerry Lohr to share his vision for entrepreneurial achievement
[Page 11] Engineering students excel in journalism
[Page 12] Entrepreneurs' Workshop schedule and registration form

Departments:
Alumni
[Page 13] Alumnus launches hydraulics …

Acuta Enews July 1990, Vol. 19, No. 5

ACUTA Newsletters

In This Issue

Long distance aggregators: A new wrinkle

Telecommunications: one of 'hottest' careers

Message From President

Portland Seminar to give full story on TMS

Do thorough check before joining aggregator

Portland Seminar to give full story on TMIS

Party Line

Touch screens may replace Touch Tone

Workstations pay for themselves in 9 months

Univ. of Chicago fits old halls with new wires

Funding sought for high speed 'data highway'

Automated Harvesting Of Burley Tobacco Ii. Evaluation Of System Performance, Larry G. Wells, George B. Day V, Timothy D. Smith

Biosystems and Agricultural Engineering Faculty Publications

A prototype system for fully automated harvesting of burley tobacco has been developed and tested. Three years of field testing has shown that mechanical losses associated with the system were only slightly higher than via conventional methods. The system performed reliably at a sustained harvesting rate of approximately 1.4 ha/day (3.4 acre/day), while indicating that a rate of 2 ha/day (5 acre/day) should be easily achievable. The system is operated by two workers and reduces conventional labor requirement by approximately 80-85%.

Automated Harvesting Of Burley Tobacco I. System Development, Larry G. Wells, George B. Day V, Timothy D. Smith

Biosystems and Agricultural Engineering Faculty Publications

A fully automated system for harvesting and handling mature buriey tobacco has been developed. This article identifies the operations essential to this harvesting concept and describes the development of the mechanisms by which they were accomplished. The system detaches, inverts and places mature plants into portable holders for air curing under waterproof covering without requiring any manual handling of the crop. Manual labor currently required to harvest buriey tobacco would be reduced by 80-85% and the system would eliminate the drudgery associated with manual handling. The harvesting system has an approximate capacity of 1.4 to 2.0 ha/day (3.5 to 5.0 …

Experimental Apparatus For Production, Cooling, And Storing Multiply Charged Ions For Charge-Transfer Measurements, Victor H. S. Kwong, T. T. Gibbons, Z. Fang, Jinhua Jiang, H. Knocke, Yingtao Jiang, B. Ruger, Su-Ching Huang, E. Braganza, W. Clark, L. D. Gardner

Electrical & Computer Engineering Faculty Research

A novel method is described that combines the production of ions by laser ablation with an ion‐trap technique for the measurement of thermal‐energy charge‐transfer rates of multiply charged ions and neutrals. The charge‐transfer rate is determined by measuring the rate of loss of stored ions from the trap. Verification of the calibration of the apparatus is demonstrated through investigation of charge transfer of N₂ and N²⁺, which has been studied by another group. We also have made the first measurement on the thermal‐energy charge‐transfer coefficient of Ar and W²⁺. The rate coefficient is 0.99(0.22)×10^{−11 …}

Irish Building Services News

Building Services Engineering

No abstract provided.

A Comparative Study Of Spectral Peaks Versus Global Spectral Shape As Invariant Acoustic Cues For Vowels, Amir Jalali Jagharghi

Electrical & Computer Engineering Theses & Dissertations

The primary objective of this study was to compare two sets of vowel spectral features, formants and global spectral shape parameters, as invariant acoustic cues to vowel identity. Both automatic vowel recognition experiments and perceptual experiments were performed to evaluate these two feature sets. First, these features were compared using the static spectrum sampled in the middle of each steady-state vowel versus features based on dynamic spectra. Second, the role of dynamic and contextual information was investigated in terms of improvements in automatic vowel classification rates. Third, several speaker normalizing methods were examined for each of the feature sets. Finally, …

An Artificial Neural Approach To The Decomposition Problem, Chandrashekar L. Masti

Electrical & Computer Engineering Theses & Dissertations

The goal of this thesis is to develop an artificial neural approach toward addressing the intractability involved with the decomposition problem. The search for the lattice of substitution property (s. p.) partitions essential to decompositions is cast into the framework of constraint satisfaction. An artificial neural network is developed to provide solutions by performing optimization of a mathematically derived objective function over the problem space. The issue of transitivity is verified to belong to a class of problems beyond the scope of solvability for conventional quadratic-order constraint satisfaction neural networks. A theorem is stated and proved establishing that third-order correlations …

Investigation Of Mixing Characteristics Of A Lox Injector Operating At Non-Ideal Thermodynamic Conditions, W. Wei

Mechanical & Aerospace Engineering Theses & Dissertations

The mixing characteristic of a liquid oxygen (LOX) injector operating under nonideal thermodynamics conditions are analyzed. Oxygen, in supercritical state, is injected into a high pressure airstream flowing through a narrow annulus region of a hypersonic wind tunnel. The objective of the present study is to investigate conditions that would help produce a uniform profile of oxygen concentration at the end of a diverging mixing channel, located downstream of the injector section. Uniformity of oxygen concentration profile is critical to combustion processes that occur downstream of the LOX injector section.

The coupled velocity, temperature, oxygen concentration and enthalpy fields are …

Grid Generation And Flow Computation About A Martian Entry Vehicle, John Edward Stewart

Mechanical & Aerospace Engineering Theses & Dissertations

A number of vehicles are currently being proposed for a manned mission to Mars. One of these vehicles has a modified blunt-nosed cone configuration. Experimental results have been obtained for this vehicle in 1968. These results show lift-over-drag ratios comparable to those needed for Mars entry. Computations are performed here to verify the earlier results and to further describe the flight characteristics of this vehicle.

An analytical method is used to define the surface of this vehicle. A single-block volume grid is generated around the vehicle using an algebraic Two-Boundary Grid Generation algorithm (TBGG) and transfinite interpolation. Euler solutions are …

Encoding Phonetic Knowledge For Use In Hidden Markov Models Of Speech Recognition, Danming Qian

Electrical & Computer Engineering Theses & Dissertations

Hidden Markov models (HMM's) have achieved considerable success for isolated-word speaker-independent automatic speech recognition. However, the performance of an HMM algorithm is limited by its inability to discriminate between similar sounding words. The problem arises because all differences between speech patterns are treated as equally important. Thus the algorithm is particularly susceptible to confusions caused by phonetically-irrelevant differences. This thesis presents two types of preprocessing schemes as candidates for improving HMM performance. The aim is to maximize the differences between phonologically-distinct speech sounds while minimizing the effect of variations in phonologically-equivalent speech sounds. The preprocessors presented are a discrete cosine …

Finite Element Analysis Of Structures With Constrained Viscoelastic Layer Damping, Yung Chen

Mechanical & Aerospace Engineering Theses & Dissertations

It has been demonstrated that constrained viscoelastic layer damping treatments provide an effective means of passive control for structural vibration. These treatments dissipate vibrational energy by inducing shear strain in a thin layer of viscoelastic material. Our interest is in adding passive damping to a structure as an augmentation to active control. For such applications it is desirable to achieve high damping performance in a given frequency range with a minimum of added weight. Most damping treatments employ spatially continuous constraining layers over the entire viscoelastic layer. Plunkett and Lee have shown that the effectiveness of the damping treatment can …

Use Of A Generalized Set Of Variables In Fluid Flow Calculations, Pawel Chwalowski

Mechanical & Aerospace Engineering Theses & Dissertations

In fluid flow calculations, a set of generalized field variables is used to replace the more conventional choice of either the conserved variables, or the primitive variables. This generalized set of variables represents an infinite number of possible choices for the specific set of field variables. For algorithms of both the implicit and explicit type, the resulting effect of a change in field variables on a steady-state flow solution is in general relatively small. However, for implicit algorithms, a consistent linearization with respect to the new variables results in dramatic changes in the overall matrix conditioning of the linear systems …

Lpsolver: A Linear Program Solving Package For Educational And Instructional Modeling Applications, Paul Savory, Jeffrey Arthur

Department of Industrial and Management Systems Engineering: Faculty Publications

LPSOLVER is a computer program developed to be a learning tool for students studying linear programming. This technical paper contains and overview of what LPSOLVER is and how to use it. The program allows one to enter linear programs in three different formats which are discussed in Section IV. Described in Section VI are the two methods available for solving linear programs. Other features of LPSOLVER are discussed in Section VII. Appendix A describes all the various files that LPSOLVER uses/creates. A listing of error messages is given in Appendix B. Information about how the program was implement is contained …

Pavement Deflection Test Database, Bobby W. Meade, David L. Allen

Kentucky Transportation Center Research Report

Pavement deflection measurements have been collected on various pavement types by both research and the Pavement Management Branch of the Transportation Cabinet for several years. This report outlines the establishment of a data base of deflection measurements which have been collected. A index program has been developed to search the available data base for pavement sections which meet given criteria. This data base will provide up-to-date information which may be used for both research and pavement management activities. The presence of historical data will assist in evaluating the structural performance of various pavement types. It will also provide additional information …

Proposed Revisions To Kentucky Revised Statutes, Theodore Hopwood Ii, Donald G. Hartman

Kentucky Transportation Center Research Report

No abstract provided.

Finite Element Formulation And Numerical Simulation Of The Large Deflection Random Vibration Of Laminated Composite Plates, Jay Howard Robinson

Mechanical & Aerospace Engineering Theses & Dissertations

A theoretical large deflection finite element formulation is developed for the purpose of simulating the random vibration of thin generally laminated composite plates. The random acoustic load is taken to be stationary and Gaussian with zero mean and uniform magnitude and phase over the surface of the plate. In­ plane inertia terms are included in the formulation however rotary inertia terms are assumed negligible.

The integration routine is derived from a set of unified single step algorithms, using a weighted satisfaction of the equilibrium equation. The algorithm is second order accurate and unconditionally stable for particular values of its free …

Navier-Stokes Simulations Of Flows About Complex Configurations Using Domain Decomposition Techniques, Kamran Fouladi-Semnani

Mechanical & Aerospace Engineering Theses & Dissertations

An algorithm is developed to obtain numerical simulations of flows about complex configurations composed of multiple and nonsimilar components with arbitrary geometries. The algorithm uses a hybridization of the domain decomposition techniques for grid generation and to reduce the computer memory requirement. Three dimensional, Reynolds-averaged, unsteady, compressible, and complete Navier-Stokes equations are solved on each of the subdomains by a fully-vectorized, finite-volume, upwind-biased, approximately-factored, and multigrid method. The effect of Reynolds stresses is incorporated through an algebraic turbulence model with several modifications for interference flows. The present algorithm combines the advantages of an efficient, geometrically conservative, minimally and automatically dissipative …

Visual Speech Training Aid For The Deaf, Subhashri Venkat

Electrical & Computer Engineering Theses & Dissertations

A computer-based vowel articulation training aid has been developed. A "continuous" acoustic-phonetic transformation is performed to map speech parameters to a lower dimensionality display space. There are two possible approaches to this transformation problem. The transformation could be either linear or a combination nonlinear/linear. The nonlinear transformation is performed using a multi-layered feedforward neural network with linear output layers. Speech parameters are extracted either from an analog filter bank arrangement (band energies) or by a digital signal processing procedure (Discrete Cosine Transform Coefficients). The speech parameters obtained from both methods correspond to the spectral envelope of the speech signals. The …

Transport Matrices Of Finite Beams Resting On Elastic Foundations, M. W. Giger

Tanzania Journal of Engineering and Technology (TJET)

A method of derivation of the coefficients of the transport matrix for a finite element resting on one and two-parameter elastic foundation soils is outlined. The coefficients are summarized for both the Bernoulli–Euler and the Timoshenko beam model in tabular form, for general reference. In addition, bounds on the parameters describing beam/soil flexure, beam and soil shear, which govern the validity of the two-parameter elastic solutions are provided in graphical form.

Damage Effects To Si-Sio2 Structures Due To Reactive Ion Etching, Moshe D. Bunyan

Theses

This thesis presents the damage effects to the Si ? SiO₂ structures due to Reactive Ion Etching (RIE). The research was carried out on Si ? SiO₂ MOS capacitors which were fabricated using RIE and wet etch (Hydrofluoric acid etch (HFE)) Process. The experiment was carried out using CV technique and Ellipsometry. Various electrical parameters were measured from CV *curves of these MOS capacitors. It was observed that the CV curve obtained for the RIE etched sample showed considerable deviation from that of the control sample. This indicates the presence of excess of interface trap charge density which …

Improving Solids Conveying In Plasticating Extruders : An Investigation Into Manufacturing Processes And Manufacturing Systems For Profiled Thermoplastic Pellets, Oommen Cherian

Theses

The objective of the thesis is the manufacture of thermoplastic bilobal and trilobal profiled pellets for the determination of the interparticulate co-efficient of friction exhibited by solid beds of such pellets. The enhancement of the interparticulate coefficient of friction is expected to lead to ameliorated solids conveying rates in plasticating extruders.

Predicting the product shape from a profile die is very difficult due to the elastic memory of plastics and the complex boundary conditions. Consequently the cost involved in experimenting with different profile dies is high. Therefore a standard die with several die inserts of varying cross-sections were used to …

Small Disturbance Stability As Affected By Excitation Controls, Alfredo Flores

Theses

The effect of excitation control systems on the power system's small disturbance stability limits has been investigated in this thesis. Three excitation control schemes namely the proportional, fast?acting and the modified fast?acting have been studied.

The stability results were predicted directly in terms of the AVR gain controlling parameters following one?dimensional and two?dimensional frequency domain separation technique. The necessary algorithms and computer simulation programs have been developed.

In case of a modified fast?acting excitation control with three unknown variables, a procedure has been proposed to obtain the stability results by extending the two?dimensional frequency domain separation technique.

Effect Of Moisture On Microcircuit Failure, Chandrabala D. Patel

Theses

Stability and reliability of microcircuit is dependent on its design, fabrication, testing, storage and use.

In this thesis emphasis is given on various failure mechanisms of Integrated Circuits in humid environment and techniques of improving reliability. Other factors which affect the failure of integrated circuits are also discussed. Moisture induced failure modes, semi-reversible failures and irreversible failures (surface leakage current and corrosion-causing interruption of interconnection lines) are also reviewed.

Controlling the contaminants and moisture related corrosion are also covered. The quickest way to evaluate the reliability of microcircuit is by accelerated aging test and by selection of meaningful criteria of …

Investigation On The Use Of Ethyl Acetate As Solvent For Seed Oil Extraction, E. L. Rivera Porras

Tanzania Journal of Engineering and Technology (TJET)

An investigation on the use of ethyl acetate as a solvent for the seedoil industry was carried out. As hexane is the most used solvent in extraction of oil from seeds, the study focuses on the comparison of the two solvents. The parameters studied were: contact time between solvent and seed cake, temperature of the solvent, quantity of solvent used for extraction and type of solvent. The results are presented on a relative basis where hexane is given a factor of 100. From the results obtained it can be seen that ethyl acetate is in general a better solvent than …

A Study Of Load Bearing Capacity Of Piles Driven In The Zanzibar Harbour Submarine Soils, A. M. Dubi

Tanzania Journal of Engineering and Technology (TJET)

The rehabilitation of the Zanzibar Port involved, among other things, driving piles into the submarine soils. Pile driving fractures the coral and as a result creates a gap filled with loose fractured coral between the unfractured coral and the pile. Grouting of the external surface of the pile is done to strengthen the fractured coral. In this paper, two grouted working piles (TP6 & TP61), randomly chosen from the pile group, were load tested to twice the design load. The test results indicate adequacy of the bearing capacity of the grouted piles.