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Building Services Engineering

No abstract provided.

Supervisory Control And Data Acquisition Experiment Using The Advanced Communications Technology Satellite - Lessons Learned, Florida Solar Energy Center, Carol Emrich

FSEC Energy Research Center®

Satellite Supervisory Control and Data Acquisition (SCADA) of a Photovoltaic (PV)/diesel hybrid system was tested using NASA's Advanced Communication Technology Satellite (ACTS) and Ultra Small Aperture Terminal (USAT) ground stations. The setup consisted of a custom-designed PV/diesel hybrid system, located at the Florida Solar Energy Center (FSEC), which was controlled and monitored at a remote hub via Ka-band satellite link connecting two USATs in a SCADA arrangement. The robustness of the communications link was tested for remote monitoring of the health and performance of a PV/diesel hybrid system, and for investigating load control and battery charging strategies to maximize battery …

Opal Press Release: October 28, 1999, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A press release written by Professor Bob Twiggs titled "Opal Press Release: October 28, 1999."

Gauge Repeatability & Reproducibility Study For A 3-D Solder Paste Inspection System, Jianbiao Pan, Gregory L. Tonkay, Robert H. Storer, Ronald M. Sallade, David J. Leandri

Industrial and Manufacturing Engineering

Due to the increased use of Ball Grid Arrays (BGAs) and fine pitch and ultra fine pitch Quad Flat Packages (QFPs), there is a dramatic increase in demand for solder paste inspection after the stencil printing process. The important response variables of the printing process are deposited solder paste volume, area, height and position. To identify and remove defects at the earliest possible process step, a 3-D solder paste inspection system should be used to monitor solder paste deposited on all pads on every board before component placement. An example is a fully automatic laser-based 3-D triangulation solder paste inspection …

Preparation Of Monolithic Carbon Fiber Composite Material, Geoffrey M. Kimber

Center for Applied Energy Research Faculty Patents

A process for preparing an activated carbon fiber composite material includes the steps of mixing carbon fibers, binder and water to form a slurry, molding the slurry to produce a green monolithic body, curing the monolithic body, carbonizing the cured monolith to produce a carbon fiber composite with an open, permeable structure and activating the composite. If pre-activated carbon fibers are utilized in the mixing step the carbonizing and activating steps are eliminated.

Letters To The Editor: Filtering Property Of A Lightly Damped System, Subjected To Transient Excitation, M. F. Dimentberg, Mohammad N. Noori

Office of the Dean (CENG) Scholarship

No abstract provided.

Methods Of Fabricating Plasticized, Antiplasticized And Crystalline Conducting Polymers And Precursors Thereof, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

Methods of forming materials containing precursors to electrically conductive polymers and electrically conductive polymers are described which have a high degree of crystallinity. The high degree of crystallinity is achieved by preparing the materials under conditions which provide a high degree of mobility to the polymer molecules permitting them to associate with one another to form a crystalline state. High levels of electrical conductivity are achieved in in the electrically conductive materials without stretch orienting the material. The enhanced electrical conductivity is isotropic as compared to a stretch oriented film which has isotropic electrical conductivity. In the preferred embodiment, additives …

Critical Variables Of Solder Paste Stencil Printing For Micro-Bga And Fine Pitch Qfp, Jianbiao Pan, Gregory L. Tonkay, Robert H. Storer, Ronald M. Sallade, David J. Leandri

Industrial and Manufacturing Engineering

Stencil printing continues to be the dominant method of solder deposition in high volume surface mount assembly. Control of the amount of solder paste deposited is critical for fine pitch and ultra-fine pitch SMT assembly. The process is still not well understood as indicated by the fact that industry reports 52-71% of SMT defects are related to the solder paste stencil printing process. The purpose of this paper is to identify the critical variables that influence the deposited solder paste volume, area, and height. An experiment was conducted to investigate the effects of relevant process parameters on the amount of …

Coulomb Crystals And Glasses For Self-Assembly Of Nanoparticles, P. F. Williams, A. Belolipetski, A. Goussev, M. E. Markes

P. F. (Paul Frazer) Williams Publications

Under proper conditions, small particles may be suspended in a regularly-spaced array called a Coulomb crystal. In this paper we discuss the application of this phenomenon to the self-assembly of nanoparticles in a lattice-lie array on a substrate. Issues associated with depositing the particles, and the size and lattice spacing of the particles are discussed.

Case Study: Modernization Of The Government Highline Canal, Stuart W. Styles, Charles M. Burt, Ram Dhan Khalsa, Robert Norman

BioResource and Agricultural Engineering

The Government Highline Canal Modernization Study was completed to evaluate options for reducing the flow rate requirement of the Government Highline Canal during the late Summer and Fall water delivery months. The intent was to develop a design for which Colorado River diversions could be better matched to on-farm demands. The two primary challenges associated with reducing diversions are that (i) at low canal flows many turnouts do not have sufficient pressure, and (ii) it is difficult to schedule diversions to match deliveries. The Government Highline Canal is part of the federal Grand Valley Project in the Colorado River Basin …

Case Study: Modernization Of The Patterson Irrigation District, Stuart W. Styles, Charles M. Burt, Mike Lehmkuhl, John Sweigard

BioResource and Agricultural Engineering

The Irrigation Training and Research Center (ITRC) at Cal Poly in San Luis Obispo, California has been working in conjunction with the Patterson Irrigation District (PID) on modernization of the district facilities. This project is being partially funded by the United States Bureau of Reclamation (USBR) Mid-Pacific Region. The district is located in the San Joaquin Valley of California. Water supply for the district is pumped primarily from the San Joaquin River. The district utilizes a series of pump stations and canal pools to bring water uphill to supply the lateral canals, which are laid out on the contour. Modernization …

Current Canal Modernization From An International Perspective, Charles M. Burt

BioResource and Agricultural Engineering

Modernization differs from rehabilitation, which simply returns a deteriorated project or structures to their original new state. Rehabilitation by itself typically only perpetuates the vicious cycle of rehabilitation, deterioration, rehabilitation, etc. A modern irrigation design is the result of a thought process that selects the configuration and the physical components in light of a well-defined and realistic operation plan that is based on the service concept. A modern irrigation design is not defined by specific hardware components and control logic. Advanced concepts of hydraulic engineering, irrigation engineering, agronomy, and social science should be used to arrive at the most simple …

Modernization Of The Delano-Earlimart Irrigation District, Charles M. Burt, Dale R. Brogan

BioResource and Agricultural Engineering

Delano-Earlimart Irrigation District (DEID) delivers water through closed reinforced concrete pipelines on an arranged schedule. Farmers are not allowed to operate their own turnouts, and individual turnout flow rate changes impact flow rates at all other turnouts on the same pipeline. DEID is in the process of a complete modernization program which will allow the farmers to operate their own turnouts on a very flexible arranged schedule. The modernization includes (i) a new water ordering program, (ii) new turnout designs with pressure regulators and new flow propeller flow meters, (iii) the use of hand held data recorders to document deliveries …

Carrier Concentration And Lattice Absorption In Bulk And Epitaxial Silicon Carbide Determined Using Infrared Ellipsometry, Thomas E. Tiwald, John A. Woollam, Stefan Zollner, Jim Christiansen, R. B. Gregory, T. Wetteroth, S. R. Wilson, Adrian R. Powell

Department of Electrical and Computer Engineering: Faculty Publications

We have measured the dielectric function of bulk nitrogen-doped 4H and 6H SiC substrates from 700 to 4000 cm^-1 using Fourier-transform infrared spectroscopic ellipsometry. Photon absorption by transverse optical phonons produces a strong reststrahlen band between 797 and 1000 cm^-1 with the effects of phonon anisotropy being observed in the region of the longitudinal phonon energy (960 to 100 cm^-1). The shape of this band is influenced by plasma oscillations of free electrons, which we describe with a classical Drude equation. For the 6H-SiC samples, we modify the Drude equation to account for the strong effective …

Opal Microsatellite, Greg Hutchins

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Greg Hutchins on the "OPAL Microsatellite" from October 8, 1999.

A Defect In Interleukin 12-Induced Activation And Interferon Gamma Secretion Of Peripheral Natural Killer T Cells In Nonobese Diabetic Mice Suggests New Pathogenic Mechanisms For Insulin-Dependent Diabetes Mellitus., Marika Falcone, Brian Yeung, Lee Tucker, Enrique Rodriguez, Nora Sarvetnick

Journal Articles: Regenerative Medicine

The function of natural killer T (NKT) cells in the immune system has yet to be determined. There is some evidence that their defect is associated with autoimmunity, but it is still unclear how they play a role in regulating the pathogenesis of T cell-mediated autoimmune diseases. It was originally proposed that NKT cells could control autoimmunity by shifting the cytokine profile of autoimmune T cells toward a protective T helper 2 cell (Th2) type. However, it is now clear that the major function of NKT cells in the immune system is not related to their interleukin (IL)-4 secretion. In …

Student Space Program: Stanford University, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Professor Bob Twiggs titled "Student Space Program: Stanford University" from October 3, 1999.

Acuta Enews October 1999, Vol.28, No. 10

ACUTA Newsletters

In This Issue

ACUTA Strategizes for the Future

ACUTA EVENTS

Three Win Achievements Awards

DC Update

Integrating H.323 Video Conferencing into an Existing H.320 System

Winter Seminars: Surf and Substance!

Welcome New Members

Positions Available

Candidate Sets For Complex Interval Arithmetic, Juergen Wolff Von Gundenberg, Vladik Kreinovich

Departmental Technical Reports (CS)

Uncertainty of measuring complex-valued physical quantities can be described by complex sets. These sets can have complicated shapes, so we would like to find a good approximating family of sets. Which approximating family is the best? We reduce the corresponding optimization problem to a geometric one: namely, we prove that, under some reasonable conditions, an optimal family must be shift-, rotation- and scale-invariant. We then use this geometric reduction to conclude that the best approximating low-dimensional families consist of sets with linear or circular boundaries. This result is consistent with the fact that such sets have indeed been successful in …

A Geometric Approach To Classification Of Trash In Ginned Cotton, Murali Siddaiah, Michael A. Lieberman, Nadipuram R. Prasad, Vladik Kreinovich

Departmental Technical Reports (CS)

This paper discusses the use of geometric approach to classify different types of trash (non-lint, non-fiber material) in ginned cotton. Pieces of trash can have complicated shapes, so we would like to find a good approximating family of sets. Which approximating family is the best? We reduce the corresponding optimization problem to a geometric one: namely, we show that, under some reasonable conditions, an optimal family must be shift-, rotation- and scale-invariant. We then use this geometric reduction to conclude that the best approximating low-dimensional families consist of sets with linear or circular boundaries.

This result is in good agreement …

Interval Methods In Non-Destructive Testing Of Material Structures, Keith Worden, Roberto A. Osegueda, Carlos M. Ferregut, Soheil Nazarian, Debra L. George, Mary J. George, Vladik Kreinovich, Olga Kosheleva, Sergio Cabrera

Departmental Technical Reports (CS)

In many practical situations, e.g., in aerospace applications and in mammography, it is important to test the structural integrity of material structures. We show that interval methods can help.

From Fuzzy Values To Intuitionistic Fuzzy Values To Intuitionistic Fuzzy Intervals Etc.: Can We Get An Arbitrary Ordering?, Vladik Kreinovich, Masao Mukaidono, Krassimir Atanassov

Departmental Technical Reports (CS)

Traditional fuzzy logic uses real numbers as truth values. This description is not always adequate, so in intuitionistic fuzzy logic, we use pairs of real numbers to describe a truth value. Such pairs can be described either as pairs (t,f) for which t+f<=1, or, alternatively, as pairs (t,1-f) for which t<=1-f. To make this description even more adequate, instead of using real numbers to described each value t and f, we can use intervals, and thus get interval-valued intuitionistic fuzzy values which can be described by 4 real numbers each. We can iterate this procedure again and again. The question is: can we get an arbitrary partially ordered set in this manner? An arbitrary lattice? In this paper, we show that although we cannot thus generate arbitrary lattices, we can actually generate an arbitrary partially ordered set in this manner. In this sense, the "intervalization" operation which underlies the notion of an intuitionistic fuzzy set, is indeed universal.

Water Resources Systems Analysis - Course Notes, A Bruce Bishop, Trevor Hughes, Mac Mckee

All ECSTATIC Materials

Water resources systems analysis course notes for CEE 6410 taught at Utah State University. Coverage includes:

Chapter 1 - Concepts and methods

Chapter 2 - Linear programming-introduction and graphical methods

Chapter 3 - Linear programming - simplex method

Chapter 4 - Linear programming - applications to simple water problems

Chapter 5 - Dual LP and post optimality analysis

Chapter 6 - Integer programming

Chapter 7 - More applications of integer programmign

Chapter 8 - Piecewise linearization

Chapter 9 - Other types of LP models

Chapter 10 - Dynamic programming

Chapter 11 - Gradient-based nonlinear optimization methods

Chapter 12 - Genetic …

Parallel Ac-Ac Converters Using Stationary Master Slave Control, Taufik, F. E. Villaseca

Electrical Engineering

This study proposes parallel ac-ac converters using Stationary Master Slave Control with Sinusoidal Pulse Width Modulation to achieve voltage regulation and equal current sharing among parallel generators such that it minimizes the total production cost. Development of Pspice model representing the parallel ac-ac converters is presented and then simulated. In addition, computer simulations are also used to perform robustness study on the parallel converters.

Temperature Dependence Of Electrical And Optical Modulation Responses Of Quantum-Well Lasers, T. Keating, Xiaomin Jin, Shun Lien Chuang, K. Hess

Electrical Engineering

We present theory and experiment for high-speed optical injection in the absorption region of a quantum-well laser and compare the results with those of electrical injection including the carrier transport effect. We show that the main difference between the two responses is the low-frequency roll-off. By using both injection methods, we obtain more accurate and consistent measurements of many important dynamic laser parameters, including the differential gain, carrier lifetime, K factor, and gain compression factor. Temperature-dependent data of the test laser are presented which show that the most dominant effect is the linear degradation of differential gain and injection efficiency …

Ole Miss Engineer 1999

Ole Miss Engineer

No abstract provided.

Introduction To Industrial Engineering: Team Tower, Paul Savory

Department of Industrial and Management Systems Engineering: Instructional Materials

Classroom exercise for IMSE 150 at the University of Nebraska-Lincoln. This goal is to introduce freshman industrial engineering students to various aspects of industrial engineering and being an engineer. One of the key areas of Industrial Engineering is quality control. Quality control is concerned with testing and inspecting a product to confirm that it meets production and customer specifications. To understand some of the basics of quality control, let’s consider the production of M&M candies.

Introduction To Industrial Engineering: Group Resume, Paul Savory

Department of Industrial and Management Systems Engineering: Instructional Materials

Classroom exercise for IMSE 150 at the University of Nebraska-Lincoln. This goal is to introduce freshman industrial engineering students to various aspects of industrial engineering and being an engineer. This ice-breaking exercise has students work in groups to create a group resume to get to know each other better.

Introduction To Industrial Engineering: Bad Human Factor Designs, Paul Savory

Department of Industrial and Management Systems Engineering: Instructional Materials

Classroom exercise for IMSE 150 at the University of Nebraska-Lincoln. This goal is to introduce freshman industrial engineering students to various aspects of industrial engineering and being an engineer. Ergonomics or human factors does not only encompass product design, but safety, and product use. A simple definition is “to make the work place safe and less stressful on the worker.” Human factors or ergonomics impacts all aspects of our lives. Let's consider each of the following examples of bad human factor designs.

Introduction To Industrial Engineering: Theme Park Design And Layout, Paul Savory

Department of Industrial and Management Systems Engineering: Instructional Materials

Classroom exercise for IMSE 150 at the University of Nebraska-Lincoln. This goal is to introduce freshman industrial engineering students to various aspects of industrial engineering and being an engineer. Plant layout and design is one of the key areas of industrial engineering. There are numerous issues that must be accounted for. A subset include: machine utilization, queueing space, and flow of materials. To provide students with an introduction to plant layout and design, let's consider designing a theme park. As we will see, many of the concepts will be the same.