Engineering Commons^™

Extension Of Modal Pushover Analysis To Compute Member Forces, Rakesh K. Goel, Anil K. Chopra

Civil and Environmental Engineering

This paper extends the modal pushover analysis (MPA) procedure for estimating seismic deformation demands for buildings to compute member forces. Seismic demands are computed for six buildings, each analyzed for 20 ground motions. A comparison of seismic demands computed by the MPA and nonlinear response history analysis (RHA) demonstrates that the MPA procedure provides good estimates of the member forces. The bias (or error) in forces is generally less than that noted in earlier investigations of story drifts and is comparable to the error in the standard response spectrum analysis (RSA) for elastic buildings. The four FEMA-356 force distributions, on …

Response To B. Maison's Discussion Of "Evaluation Of Modal And Fema Pushover Analyses: Sac Buildings", Rakesh K. Goel, Anil K. Chopra

Civil and Environmental Engineering

No abstract provided.

Cec Agricultural Peak Load Reduction Program - Water Agencies Final Report, Charles M. Burt, Daniel J. Howes

BioResource and Agricultural Engineering

During the winter of 2000-2001, California experienced a severe imbalance in electricity supply and demand that resulted in blackouts and brownouts. The state legislature initiated a number of emergency programs, one of which was Senate Bill 5x. The primary goal of SB 5x is to reduce peak period electric demand throughout California. The California Energy Commission (CEC), acting under authority of Section 5(b) of the legislation, developed the “Agricultural Peak Load Demand Program”. The program was funded in early June 2001, and the Irrigation Training and Research Center (ITRC) of California Polytechnic State University (Cal Poly), San Luis Obispo was …

Uncertainty In Projections Of Streamflow Changes Due To Climate Change In California, Edwin P. Maurer, Philip B. Duffy

Civil, Environmental and Sustainable Engineering

Understanding the uncertainty in the projected impacts of climate change on hydrology will help decision-makers interpret the confidence in different projected future hydrologic impacts. We focus on California, which is vulnerable to hydrologic impacts of climate change. We statistically bias correct and downscale temperature and precipitation projections from 10 GCMs participating in the Coupled Model Intercomparison Project. These GCM simulations include a control period (unchanging CO2 and other forcing) and perturbed period (1%/year CO2 increase). We force a hydrologic model with the downscaled GCM data to generate streamflow at strategic points. While the different GCMs predict significantly different regional climate …

Anti-Icing Coatings And Methods, Russell G. Alger

Michigan Tech Patents

A method of inhibiting or preventing bonding between snow or ice and a substrate is provided. The method includes applying an adhesive to the substrate, broadcasting an aggregate onto the adhesive to form an aggregate-adhesive and applying an anti-icing chemical onto the aggregate- adhesive.

To Properly Reflect Physicists' Reasoning About Randomness, We Also Need A Maxitive (Possibility) Measure, Andrei M. Finkelstein, Olga Kosheleva, Vladik Kreinovich, Scott A. Starks, Hung T. Nguyen

Departmental Technical Reports (CS)

According to the traditional probability theory, events with a positive but very small probability can occur (although very rarely). For example, from the purely mathematical viewpoint, it is possible that the thermal motion of all the molecules in a coffee cup goes in the same direction, so this cup will start lifting up.

In contrast, physicists believe that events with extremely small probability cannot occur. In this paper, we show that to get a consistent formalization of this belief, we need, in addition to the original probability measure, to also consider a maxitive (possibility) measure.

Specification Of A Common Framework For Characterizing Alignment, Paolo Bouquet, Marc Ehrig, Jerome Euzenat, Enrico Franconi, Pascal Hitzler, Markus Krotzsch, Luciano Serafini, Giorgos Stamu, York Sure, Sergio Tessaris

Computer Science and Engineering Faculty Publications

Definition of a common framework for characterizing alignment of heterogeneous information. This report describes various approaches towards this goal and shows the relations between them. It also provides a description of the alignment sructure and process.

Ccfss News Spring 2005, Wei-Wen Yu Center For Cold-Formed Steel Structures

CCFSS Newsletters (1999 - 2008)

No abstract provided.

Measuring Relative Humidity In Agricultural Environments, George A. Duncan, Rich Gates, Michael D. Montross

Agricultural Engineering Extension Publications

Relative humidity is very important for many agricultural environments, such as fruit and vegetable storage facilities, greenhouses, and tobacco curing and handling facilities.

Several scientific instruments measure temperature and relative humidity. The more accurate the instrument, the more it will cost. Devices that are economical for agricultural use in a barn, greenhouse, or a semi-protected environment often do not hold their accuracy over very long periods (six months to a year or longer) if they are used carelessly.

Several instruments that are readily available and affordable for general farm use are described here. Often called hygrometers or hygro-thermometers, some …

The Matrix Pencil For Power System Modal Extraction, A. Singh, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

This work introduces the matrix pencil modal extraction method through the use of several illustrative examples. This method is used to estimate the eigenvalues of reduced-order models of large nonlinear systems based on their dynamic responses.

Teacher In The Spotlight, Beverly Stout

Lake Union Herald

No abstract provided.

High-Anisotropy Nanocluster Films For High-Density Perpendicular Recording, David J. Sellmyer, Minglang Yan, Yinfan Xu, Ralph Skomski

Materials Research Science and Engineering Center: Faculty Publications

This paper reports results on the synthesis and magnetic properties of L1₀:X nanocomposite films, where L1₀ = FePt, CoPt, and X = C, Ag, etc. Two fabrication methods are discussed: nonepitaxial growth of oriented perpendicular media, and monodispersed nanoparticle-assembled films grown with a gas-aggregation source. The magnetic properties are controllable through variations in the nanocluster properties and nanostructure. The films show promise for development as recording media at extremely high areal densities.

Improving Voltage Stability By Reactive Power Reserve Management, Feng Dong, Badrul H. Chowdhury, Mariesa Crow, Levent Acar

Electrical and Computer Engineering Faculty Research & Creative Works

The amount of reactive reserves at generating stations is a measure of the degree of voltage stability. With this perspective, an optimized reactive reserve management scheme based on the optimal power flow is proposed. Detailed models of generator limiters, such as those for armature and field current limiting must be considered in order to utilize the maximum reactive power capability of generators, so as to meet reactive power demands during voltage emergencies. Participation factors for each generator in the management scheme are predetermined based on the voltage-var (V-Q) curve methodology. The Bender's decomposition methodology is applied to the reactive reserve …

Pulse Regulation Control Technique For Integrated High-Quality Rectifier-Regulators, Mehdi Ferdowsi, Ali Emadi

Electrical and Computer Engineering Faculty Research & Creative Works

The pulse regulation control scheme is presented and applied to the boost integrated flyback rectifier/energy storage dc/dc (BIFRED) converter as the most popular member of the integrated high-quality rectifier-regulators (IHQRR). In contrast to the conventional control techniques, the principal idea of pulse regulation is to regulate the output voltage using a series of high- and low-power pulses generated by the current of the input inductor, which is operating in discontinuous conduction mode (DCM). Analysis of the BIFRED converter operating in DCM is presented. Fundamentals of pulse regulation as well as its stability analysis and the estimation of the output voltage …

Reinforcement Learning-Based Output Feedback Control Of Nonlinear Systems With Input Constraints, Pingan He, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

A novel neural network (NN) -based output feedback controller with magnitude constraints is designed to deliver a desired tracking performance for a class of multi-input-multi-output (MIMO) discrete-time strict feedback nonlinear systems. Reinforcement learning in discrete time is proposed for the output feedback controller, which uses three NN: 1) a NN observer to estimate the system states with the input-output data; 2) a critic NN to approximate certain strategic utility function; and 3) an action NN to minimize both the strategic utility function and the unknown dynamics estimation errors. The magnitude constraints are manifested as saturation nonlinearities in the output feedback …

Modelling And Validation Of A Propellant Mixer For Controller Design, Hanz Richter, Enrique Barbieri, Fernando Figueroa Nasa Stennis Space Center

Mechanical Engineering Faculty Publications

A mixing chamber used in rocket engine testing at the NASA Stennis Space Center is modelled by a system of two nonlinear ordinary differential equations. The mixer is used to condition the thermodynamic properties of cryogenic liquid propellant by controlled injection of the same substance in the gaseous phase. The three inputs of the mixer are the positions of the valves regulating the liquid and gas flows at the inlets, and the position of the exit valve regulating the flow of conditioned propellant. Mixer operation during a test requires the regulation of its internal pressure, exit mass flow, and exit …

Evaluation Of Alternate Cable Anchor Designs And Three-Cable Guardrail Adjacent To Steep Slope, Ryan M. Nelson, Dean L. Sicking, Ronald K. Faller, John D. Reid, John R. Rohde, Karla A. Polivka, Jason A. Hascall

Nebraska Department of Transportation: Research Reports

No abstract provided.

Catalytic Wet Air Oxidation Of Phenol In Concurrent Downflow And Upflow Packed-Bed Reactors Over Pillared Clay Catalyst, Jing Guo, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

An Experimental Study is Presented for Comparing the Behavior of a Packed Bed Reactor in the Catalytic Liquid-Phase Oxidation of Aqueous Phenol with Two Modes of Operation, Downflow and Upflow. the Operating Parameters Investigated Included Temperature, Reactor Pressure, Gas Flowrate, Liquid Hourly Space Velocity and Feed Concentration. Because of the Completely Wetted Catalyst, the Upflow Reactor Generally Performs Better for High Pressures and Low Feed Concentrations When the Liquid Reactant Limitation Controls the Rate. the Interaction between the Reactor Hydrodynamics, Mass Transfer, and Reaction Kinetics is Discussed. for Both Operation Modes, Complete Phenol Removal and Significant Total Organic Carbon (TOC) …

Towards A Minimal Metrics Suite For Agent Based Systems, Maha Ahmed Nabil Abdel Kader

Archived Theses and Dissertations

No abstract provided.

Composting For Organic Agriculture, Mona Mohamed Hamdy Mostafa Sayed Ahmed

Archived Theses and Dissertations

No abstract provided.

Environmental Risk Assessment Model, Ahmed Hammam El-Sherbiny

Archived Theses and Dissertations

No abstract provided.

Using Neural Networks To Identify The Effect Of Construction Factors On The Cost Of Reinforced Concrete Elements, Ahmed Aly El-Sotouhy

Archived Theses and Dissertations

No abstract provided.

Ferrocement Sandwich And Hollow Core Panels For Floor And Wall Construction, Hassan Mohammed Gaafar

Archived Theses and Dissertations

No abstract provided.

Dimensionality Reduction Of Feature Space In Pattern Analysis, Basma Fathi Hussain

Archived Theses and Dissertations

An important factor affecting the classifier performance is the feature size. It is desired to minimize the feature size due to its effect on measurement cost and classifier accuracy. Both Principle Component Analysis (PCA) and Linear Discriminant Analysis (LDA) are statistical approaches for "Dimensionality Reduction" that are based on linear transformation, but are unsuitable for applications that are highly nonlinear functions of the original data. In this thesis, the effect of applying approximation methods on dimensionality reduction of feature space in pattern analysis is examined. The approximation methods are applied either in the signal domain or the transform domain. Mathematical …

A Graph-Based Model For Component-Based Software Development, Sahra Sedigh, Arif Ghafoor

Electrical and Computer Engineering Faculty Research & Creative Works

Software metrics can be used to objectively quantify the quality of software components and systems, alleviating quality and risk concerns and raising assurance in component-based systems. In this paper, we present a graph-based model for component-based software development. We assume that a number of components have been characterized in terms of non-functional metrics of importance to the software system being developed, and that the interfaces connecting various components have been similarly characterized. The emphasis of this work is on cost and quality of the system under development, and reaching an acceptable compromise between the two.

Work In Progress - Automated Discourse Interventions And Student Teaming, Ray Luechtefeld, Steve Eugene Watkins, Ralph E. Flori

Engineering Management and Systems Engineering Faculty Research & Creative Works

The ability to successfully work in teams is a crucial part of an engineer's workplace success. Engineering education can be improved through a better understanding of how effective teamwork develops. A (patent pending) software tool that "listens" to team conversations and generates automatic interventions into team discourse can effectively mimic the actions of a skilled facilitator. Automated facilitation tools may help students improve their team skills by providing a simplified model for conversational interventions, which students can readily imitate. This paper describes this tool and presents preliminary findings from student reactions to the tool's use.

Development And Evaluation Of Lime Mortars For Restoration Of Historic Buildings And Monuments, Tarek Said Mahfouz

Archived Theses and Dissertations

Monuments and historic buildings and sites are regarded as a national treasure of any country. This is particularly true for Egypt that possesses a wealth of historic and heritage buildings covering the entire life span of human civilization. It must be preserved and safeguarded not only as historic evidences but also as works of art. Most of these structures used lime based mortars as binding material. These structures are deteriorating at a rate faster than our ability to renovate them. The repair and rehabilitation of old historic walls and mortars involve a complex interaction of existing and new elements. Engineers …

Improved Compressed Earth Blocks, Tarek Mahmoud Ahmed Elgindy

Archived Theses and Dissertations

Bricks and blocks, being two of the most important building materials in our construction field, can be made out of different materials, most popular of which are earthen materials. Ancient civilizations used earthen materials as a cheap and easy way to make bricks from which they built their houses and shelters. Ancient Egyptians used "mud" (which is technically silt and clay) to make bricks which we call now adobe. These days, despite the low cost of adobe it is loosing grounds in the construction of housing because of its very low compressive strength and poor durability against weathering. Accordingly, cement …

Bs News

Building Services Engineering

No abstract provided.

A Virtual Environment For Remote Testing Of Complex Systems, Loredana Cristaldi, Alessandro Ferrero, Antonello Monti, Ferdinanda Ponci, William Mckay, Roger A. Dougal

Faculty Publications

Complex systems, realized by integration of several components or subsystems, pose specific problems to simulation environments. It is, in fact, desirable to simulate the complex system altogether, and not component by component, since the operation of the single part depends on the surrounding system and an early verification can prevent damages and save time for modifications. The availability of detailed and validated models of the single parts is therefore critical. This task may be difficult to achieve. In fact, in industrial applications, where a system can be a mix of different devices produced by different manufacturers, the physical device may …