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Level Oriented Formal Model For Asynchronous Circuit Verification And Its Efficient Analysis Method, Eric G. Mercer, Tomoya Kitai, Chris Myers, Yusuke Oguro, Tomohiro Yoneda Dec 2002

Level Oriented Formal Model For Asynchronous Circuit Verification And Its Efficient Analysis Method, Eric G. Mercer, Tomoya Kitai, Chris Myers, Yusuke Oguro, Tomohiro Yoneda

Faculty Publications

Using a level-oriented model for verification of asynchronous circuits helps users to easily construct formal models with high readability or to naturally model datapath circuits. On the other hand, in order to use such a model on large circuits, techniques to avoid the state explosion problem must be developed. This paper first introduces a level-oriented formal model based on time Petri nets, and then proposes its partial order reduction algorithm that prunes unnecessary state generation while guaranteeing the correctness of the verification.


On-Chip Actuation Of An In-Plane Compliant Bistable Micromechanism, Michael S. Baker, Larry L. Howell Dec 2002

On-Chip Actuation Of An In-Plane Compliant Bistable Micromechanism, Michael S. Baker, Larry L. Howell

Faculty Publications

A compliant bistable micromechanism has been developed which can be switched in either direction using on-chip thermal actuation. The energy storage and bistable behavior of the mechanism is achieved through the elastic deflection of compliant segments. The Pseudo-Rigid-Body Model was used for the compliant mechanism design, and for analysis of the large deflection flexible segments. To achieve on-chip actuation, the mechanism design was optimized to allow it to be switched using linear motion thermal actuators. The modeling theory and analysis are presented for three design iterations, with two iterations fabricated in the MUMP's process and the third in the SUMMiT …


An Assessment Of Seawinds On Quikscat Wind Retrieval, David Draper, David G. Long Dec 2002

An Assessment Of Seawinds On Quikscat Wind Retrieval, David Draper, David G. Long

Faculty Publications

The scatterometer ocean wind retrieval process produces several possible solutions or ambiguities at each point, requiring a separate ambiguity selection step to infer a unique wind vector field. An ambiguity selection error occurs when the selected wind vector is not the closest ambiguity to the true wind. The current ambiguity selection routine for SeaWinds is ad hoc, but performs well under most circumstances. Factors such as instrument noise and rain can also cause the estimated wind flow to deviate from the true wind. A quality assurance (QA) analysis is performed to assess the ambiguity selection effectiveness and noise level of …


Coordinated Target Assignment And Intercept For Unmanned Air Vehicles, Erik P. Anderson, Randal W. Beard, Michael A. Goodrich, Timothy W. Mclain Dec 2002

Coordinated Target Assignment And Intercept For Unmanned Air Vehicles, Erik P. Anderson, Randal W. Beard, Michael A. Goodrich, Timothy W. Mclain

Faculty Publications

This paper presents an end-to-end solution to the cooperative control problem represented by the scenario where unmanned air vehicles (UAVs) are assigned to transition through known target locations in the presence of dynamic threats. The problem is decomposed into the subproblems of: 1) cooperative target assignment; 2) coordinated UAV intercept; 3) path planning; 4) feasible trajectory generation; and 5) asymptotic trajectory following. The design technique is based on a hierarchical approach to coordinated control. Simulation results are presented to demonstrate the effectiveness of the approach.


Development And Design Of Constant-Force Mechanisms, Brent Lewis Weight Nov 2002

Development And Design Of Constant-Force Mechanisms, Brent Lewis Weight

Theses and Dissertations

This thesis adds to the knowledge base of constant-force mechanisms (CFMs). It begins by reviewing past work done in the area of CFMs and then develops new nondimensionalized parameters that are used to simplify the calculations required to design a CFM. Comparison techniques are then developed that utilize these non-dimensionalized parameters to compare mechanisms based on stiffnesses, percent constant-force, actual lengths, normal displacements, and feasible design orientations. These comparison techniques are then combined with optimization to define new mechanisms with improved performance and range of capabilities. This thesis also outlines a design process, methods to identify mechanisms that are suitable …


Mapping The Mesoscale Interface Structure In Polycrystalline Materials, Brent L. Adams, C. L. Bauer, D. Casasent, A. Morawiec, S. Ozdemir, A. Talukder, Chialin T. Wu Nov 2002

Mapping The Mesoscale Interface Structure In Polycrystalline Materials, Brent L. Adams, C. L. Bauer, D. Casasent, A. Morawiec, S. Ozdemir, A. Talukder, Chialin T. Wu

Faculty Publications

This work was supported primarily by the MRSEC Program of the National Science Foundation under Award Numbers DMR-9632556 and DMR-0079996. A new experimental approach to the quantitative characterization of polycrystalline microstructure by scanning electron microscopy is described. Combining automated electron backscattering diffraction with conventional scanning contrast imaging and with calibrated serial sectioning, the new method (Mesoscale Interface Mapping System, MIMS) recovers precision estimates of the 3-dimensional idealized aggregate function G(x). This function embodies a description of lattice phase and orientation (limiting resolution ~ 1 degree) at each point x (limiting spatial resolution ~ 100 nanometers), and therefore contains a complete …


Modeling The Multicast Address Allocation Problem, Daniel Zappala, Chris Gauthierdickey, Virginia Lo Nov 2002

Modeling The Multicast Address Allocation Problem, Daniel Zappala, Chris Gauthierdickey, Virginia Lo

Faculty Publications

To support IP multicast, domains must assign a unique multicast address to each application from a limited, globally-shared address space. We examine the performance of several classes of address allocation algorithms withln the context of the MASC architecture. This study is the first of its kind to model the generalized multicast address allocation problem and consider non-contiguous allocation algorithms. We find that prefix-based allocation outperforms our non-contiguous algorithm, despite the apparent advantages of non-contiguous allocation. We also verify the benefits of using worst-fit for new allocations.


A History Of The Latter-Day Saints In The Columbia Basin Of Central Washington 1850-1972, Rick B. Jorgensen Nov 2002

A History Of The Latter-Day Saints In The Columbia Basin Of Central Washington 1850-1972, Rick B. Jorgensen

Theses and Dissertations

The Columbia Basin of Central Washington has a relatively recent Latter-day Saint history among the regions of the western states. Most of the sparsely populated rural areas in the west that have large concentrations of Latter-day Saints were originally established as "Mormon" settlements. The basin referred to lies between the Snake and Columbia Rivers and now has thousands of Latter-day Saints who have chosen to inhabit the historically barren land and call it their home. A brief visit or casual observance of the area leads many to question what were the major factors and characteristics leading to the twentieth century …


A Heterotrophic Desert Stream? The Role Of Sediment Stability, Urs Uehlinger, Markus Naegeli, Stuart G. Fisher Oct 2002

A Heterotrophic Desert Stream? The Role Of Sediment Stability, Urs Uehlinger, Markus Naegeli, Stuart G. Fisher

Western North American Naturalist

In autumn 1998 stream metabolism was measured in the Hassayampa River, Arizona, a Sonoran Desert stream, using single-station diel oxygen curves and an oxygen mass balance model. Oxygen consumption rates of parafluvial and channel sediments were determined with respiration chambers. Bedload of channel sediments (sand) prevented significant primary production by benthic autotrophs, despite favorable nutrient, light, and temperature conditions. Ecosystem respiration was relatively low (1.50 g O2 m−2d−1) and presumably fueled by production in the riparian zone and riverine marshes. Respiration rates in the parafluvial zone and in channel sediments ranged from 0.6 to 1.4 …


Horizon Occlusion Culling For Real-Time Rendering Of Hierarchical Terrains, Parris K. Egbert, Brandon Lloyd Oct 2002

Horizon Occlusion Culling For Real-Time Rendering Of Hierarchical Terrains, Parris K. Egbert, Brandon Lloyd

Faculty Publications

We present a technique to perform occlusion culling for hierarchical terrains at run-time. The algorithm is simple to implement and requires minimal pre-processing and additional storage, yet leads to 2-4 times improvement in framerate for views with high degrees of occlusion. Our method is based on the well-known occlusion horizon algorithm. We show how to adapt the algorithm for use with hierarchical terrains. The occlusion horizon is constructed as the terrain is traversed in an approximate front to back ordering. Regions of the terrain are compared to the horizon to determine when they are completely occluded from the viewpoint. Culling …


Rf Rendez-Blue: Reducing Power And Inquiry Costs In Bluetooth-Enabled Mobile Systems, Eric S. Hall, Charles D. Knutson, David K. Vawdrey Oct 2002

Rf Rendez-Blue: Reducing Power And Inquiry Costs In Bluetooth-Enabled Mobile Systems, Eric S. Hall, Charles D. Knutson, David K. Vawdrey

Faculty Publications

In resource-limited mobile computing devices, Bluetooth wireless technology imposes a weighty burden due to inefficient power utilization and a sluggish device discovery process. Buttressing Bluetooth with Radio Frequency Identification (RFID) technology by performing an operation we call “Rendez-Blue” alleviates these limitations. In the Rendez-Blue process, an RFID signal is used as a cue to “wake-up” a sleeping Bluetooth radio. This ensures that the Bluetooth radio is active only when needed, significantly reducing power consumption. In addition, RFID is used to communicate Bluetooth device information, allowing the user to bypass the traditional 10.24-second discovery process.


Full Issue Oct 2002

Full Issue

Inscape

No abstract provided.


An Assessment Of Innovative Dating In Recent Studies Of Ancient Civilization, Rosco C. Hinkle Oct 2002

An Assessment Of Innovative Dating In Recent Studies Of Ancient Civilization, Rosco C. Hinkle

Comparative Civilizations Review

No abstract provided.


David Keys, Catastrophe: A Quest For The Origins Of The Modern World., Laina Farhat-Holzman Oct 2002

David Keys, Catastrophe: A Quest For The Origins Of The Modern World., Laina Farhat-Holzman

Comparative Civilizations Review

No abstract provided.


Photographs Of Joseph F. Smith And The Laie Plantation, Hawaii, 1899, Brian William Sokolowsky Oct 2002

Photographs Of Joseph F. Smith And The Laie Plantation, Hawaii, 1899, Brian William Sokolowsky

BYU Studies

On January 7, 1899, Joseph F. Smith, then a Counselor to Church President Lorenzo Snow, left Salt Lake City to visit the Church's plantation in Laie, Hawaii. The main purpose for this trip to Hawaii was to benefit the health of President Smith's wife Sarah Ellen Richards Smith, who had just passed through a "very severe illness." They were accompanied by two of his daughters, Minerva and Alice. President Smith's "loyal friend and former missionary companion" Albert W. Davis and Edna Davis, Albert Davis's daughter, were also on the trip. They first went by train to San Francisco and on …


Editor's Note, Joseph Drew Oct 2002

Editor's Note, Joseph Drew

Comparative Civilizations Review

No abstract provided.


The Night That Marvin Gimler Shined, Nathan K. Chai Oct 2002

The Night That Marvin Gimler Shined, Nathan K. Chai

Inscape

No abstract provided.


Bluetooth: An Emerging Technology For Wireless Personal Area Networks, Eric S. Hall, Charles D. Knutson, David K. Vawdrey Oct 2002

Bluetooth: An Emerging Technology For Wireless Personal Area Networks, Eric S. Hall, Charles D. Knutson, David K. Vawdrey

Faculty Publications

Look under your desk or behind your computer. See that rat’s nest of wires and cables? Almost every cable or wire that tethers us to our devices (or our devices to one another) is unnecessary. Bluetooth wireless technology promises to reduce the cabling chaos that afflicts us all. Bluetooth is a recently developed technology that uses radio frequency (RF) transceivers to provide point-to-multipoint wireless connectivity within a personal space. Bluetooth was designed for both voice and data communication at low per-unit costs while consuming little power. To achieve the cost and power goals, Bluetooth limits connectivity to a sphere of …


Vol. 03 No. 3 Religious Educator, Religious Educator Sep 2002

Vol. 03 No. 3 Religious Educator, Religious Educator

Religious Educator: Perspectives on the Restored Gospel

No abstract provided.


The Perpetual Education Fund: A Prophet's Rescuing Hand, John K. Carmack Sep 2002

The Perpetual Education Fund: A Prophet's Rescuing Hand, John K. Carmack

Religious Educator: Perspectives on the Restored Gospel

No abstract provided.


Spanish Censuses Of The Sixteenth Century, George R. Ryskamp Sep 2002

Spanish Censuses Of The Sixteenth Century, George R. Ryskamp

BYU Family Historian

No abstract provided.


Modeling The Thermal Behavior Of A Surface-Micromachined Linear-Displacement Thermomechanical Microactuator, Christian D. Lott, Timothy W. Mclain, John N. Harb, Larry L. Howell Sep 2002

Modeling The Thermal Behavior Of A Surface-Micromachined Linear-Displacement Thermomechanical Microactuator, Christian D. Lott, Timothy W. Mclain, John N. Harb, Larry L. Howell

Faculty Publications

Thermomechanical microactuators possess a number of desirable attributes including ease of fabrication and large force and displacement capabilities relative to other types of microactuators. These advantages provide motivation for improving thermomechanical microactuator designs that are more energy efficient and thus better suited for low-power applications. To this end, this paper describes the development and experimental validation of a finite-difference thermal model of a thermomechanical in-plane microactuator (TIM). Comparisons between the model and experimental results demonstrate the importance of including the temperature dependence of several parameters in the model. Strategies for reducing the power and energy requirements of the TIM were …


Pray Always (D&C 19:38), S. Brent Farley Sep 2002

Pray Always (D&C 19:38), S. Brent Farley

Religious Educator: Perspectives on the Restored Gospel

No abstract provided.


Investigating The Mechanism Of Acoustically Activated Uptake Of Drugs From Pluronic Micelles, Ghaleb A. Husseini, Christopher M. Runyan, William G. Pitt Aug 2002

Investigating The Mechanism Of Acoustically Activated Uptake Of Drugs From Pluronic Micelles, Ghaleb A. Husseini, Christopher M. Runyan, William G. Pitt

Faculty Publications

Background

This paper examines the mechanism of ultrasonic enhanced drug delivery from Pluronic micelles. In previous publications by our group, fluorescently labeled Pluronic was shown to penetrate HL-60 cells with and without the action of ultrasound, while drug uptake was increased with the application of ultrasound.

Methods

In this study, the amount of uptake of two fluorescent probes, Lysosensor Green (a pH-sensitive probe) and Cell Tracker Orange CMTMR (a pH-independent probe), was measured in HL-60 and HeLa cells.

Results

The results of our experiments show that the increase in drug accumulation in the cells as a result of ultrasonication is …


Algebraic Methods For Computer Aided Geometric Design, Thomas W. Sederberg, Jianmin Zheng Aug 2002

Algebraic Methods For Computer Aided Geometric Design, Thomas W. Sederberg, Jianmin Zheng

Faculty Publications

CAGD draws from several branches of mathematics and computer science, such as approximation theory, differential geometry, and numerical analysis. This chapter reviews some of the tools of algebra and algebraic geometry that have been brought to bear on problems in CAGD.


Viewpoint: Experimental Recovery Of Geometrically Necessary Dislocation Density In Polycrystals, Brent L. Adams, Bassem S. El-Dasher, Anthony D. Rollett Aug 2002

Viewpoint: Experimental Recovery Of Geometrically Necessary Dislocation Density In Polycrystals, Brent L. Adams, Bassem S. El-Dasher, Anthony D. Rollett

Faculty Publications

The authors wish to thank The Alcoa Technical Research Center for supplying the specimens and performing the compression tests. This work was supported primarily by the MRSEC program of the National Science Foundation under DMR-0079996. Application of electron backscattering diffraction methods to recover estimates of the geometrically necessary dislocation density is described. The limitations of the method arising from the opacity of crystalline materials and the spatial and angular resolution limits are discussed.


Modification Of All-Hexadedral Finite Element Meshes By Dual Sheet Insertion And Extraction, Michael J. Borden Aug 2002

Modification Of All-Hexadedral Finite Element Meshes By Dual Sheet Insertion And Extraction, Michael J. Borden

Theses and Dissertations

The development of algorithms that effectively modify all-hexahedral finite element mesh is currently an active area of research. Mesh modification can be used to improve mesh quality reduce the time required to mesh a model, and improve the finite element analysis results. However, general modification of all-hexahedral meshes has proven difficult because of the global effects of local modifications. This thesis explains the global constraints on modifying all-hexahedral meshes and then presents three mesh modification techniques that make it possible to do local modifications while accounting for the global effects. These techniques are sheet insertion, sheet extraction, and mesh cutting. …


Experimental Demonstration Of Multiple Robot Cooperative Target Intercept, Timothy W. Mclain, Randal W. Beard, Jed M. Kelsey Aug 2002

Experimental Demonstration Of Multiple Robot Cooperative Target Intercept, Timothy W. Mclain, Randal W. Beard, Jed M. Kelsey

Faculty Publications

This paper presents experimental results for the simultaneous intercept of preassigned targets by a team of mobile robots. The robots are programmed to mimic the dynamic behavior of unmanned air vehicles in constant-altitude flight. In proceeding to their targets, robots must avoid both known static threats and pop-up threats. An overview of the cooperative control strategy followed is given, as well as a description of the robot hardware and software used. Experimental results demonstrating simultaneous intercept of targets by the robot team are presented.


An Interview With John L. Sorenson, Journal Of Book Of Mormon Studies Jul 2002

An Interview With John L. Sorenson, Journal Of Book Of Mormon Studies

Journal of Book of Mormon Studies

Editors of the Journal of Book of Mormon Studies interview renowned Book of Mormon scholar John L. Sorenson to discuss his experience in doing Book of Mormon research for more than fifty years. Sorensen tells of becoming interested in the Book of Mormon and in Mesoamerican anthropology and archaeology. He also articulates how to be a faithful member of the Church of Jesus Christ of Latter-day Saints while conducting objective and scholarly research on the Book of Mormon. Sorenson explains how this approach has helped people throughout the world better understand the Book of Mormon and how it will continue …


A New Approach In Parameterisation Of Momentum Transport Inside And Above Forest Canopy Under Neutral Conditions, B. Lalic, Dragutin T. Mihailović Jul 2002

A New Approach In Parameterisation Of Momentum Transport Inside And Above Forest Canopy Under Neutral Conditions, B. Lalic, Dragutin T. Mihailović

International Congress on Environmental Modelling and Software

The forest as an underlying surface is often met in atmospheric models of different scales. Experimental evidence indicates that there is a significant departure of the wind profile within the forest and in the so-called transition layer above it. In the forest environment, the observed values are rather different than the values of the wind speed profile obtained by: a) the logarithmic relationship in the transition layer and b) K theory within the forest. This situation can seriously disturb the real physical picture concerning the transfer of momentum, heat and water vapour from the surface into the atmosphere. In order …