Digital Commons Network^™

Improved Signal Integrity In Ieee 1149.1 Boundary Scan Designs, Efren De Jesus Rangel Taboada

Theses and Dissertations

This work is an analysis of solutions to problems derived from inherent timing and signal integrity issues in the use and application of the IEEE 1149.1 Standard at the board level in conjunction with its test system. Setup or hold times violations may occur in a boundary scan chain using IEEE 1149.1 compliant devices. A practical study of the TDI-TDO scan data path has been conducted to show where problems may arise in relationship to a particular board topology and test system. This work points to differences between passing and failing scan path tests for problem characterization. Serial data flow …

Thermally Developing Electro-Osmotic Convection In Circular Microchannels, Spencer L. Broderick

Theses and Dissertations

Thermally developing, electro-osmotically generated flow has been analyzed for a circular microtube under imposed constant wall temperature (CWT) and constant wall heat flux (CHF) boundary conditions. Established by a voltage potential gradient along the length of the microtube, the hydrodynamics of such a flow dictate either a slug flow velocity profile (under conditions of large tube radius-to-Debye length ratio, a/lambda_d) or a family of electro-osmotic flow (EOF) velocity profiles that depend on a/lambda_d. The imposed voltage gradient results in Joule heating in the fluid with an associated volumetric source of energy. For this scenario coupled with a slug flow velocity …

How Cellular Movement Determines The Collective Force Generated By The Dictyostelium Discoideum Slug, J. C. Dallon, H. G. Othmer

Faculty Publications

How the collective motion of cells in a biological tissue originates in the behavior of a collection of individuals, each of which responds to the chemical and mechanical signals it receives from neighbors, is still poorly understood. Here we study this question for a particular system, the slug stage of the cellular slime mold Dictyostelium discoideum. We investigate how cells in the interior of a migrating slug can effectively transmit stress to the substrate and thereby contribute to the overall motive force. Theoretical analysis suggests necessary conditions on the behavior of individual cells, and computational results shed light on experimental …

A Review Of Antennas And Propagation For Mimo Wireless Communications, Michael A. Jensen, Jon W. Wallace

Faculty Publications

Multiple-input-multiple-output (MIMO) wireless systems use multiple antenna elements at transmit and receive to offer improved capacity over single antenna topologies in multipath channels. In such systems, the antenna properties as well as the multipath channel characteristics play a key role in determining communication performance. This paper reviews recent research findings concerning antennas and propagation in MIMO systems. Issues considered include channel capacity computation, channel measurement and modeling approaches, and the impact of antenna element properties and array configuration on system performance. Throughout the discussion, outstanding research questions in these areas are highlighted.

Evaluating The Use Of Morphometric Measurements From Museum Specimens For Sex Determination In Mountain Plovers (Charadrius Montanus), William M. Iko, Stephen J. Dinsmore, Fritz L. Knopf

Western North American Naturalist

The Mountain Plover (Charadrius montanus) is a shorebird species endemic to the dry, terrestrial ecosystems of the Great Plains and southwestern United States. Breeding Bird Survey data suggest that Mountain Plover populations have declined by >60% in the last 30 years. A better understanding of the population dynamics of the Mountain Plover is important in determining future management goals for this species. However, this effort is hampered by the inability to determine the sex of Mountain Plovers accurately under field conditions. In an effort to develop a simple method for sexing plovers in the hand, we measured external …

Native Plant Community Composition And Genetic Diversity Associated With Long-Term Weed Invasions, Brian A. Mealor, Ann L. Hild, Nancy L. Shaw

Western North American Naturalist

Many studies have assessed genetic changes in exotic plant species in their native and introduced ranges, but none have focused on genetic variation in native plant species in response to exotic invasion. We examine characteristics of native plant communities within and outside old (>25 year) invasions of Acroptilon repens (Russian knapweed) and Cardaria draba (hoary cress). We also document genetic variability of 4 native grass populations (Hesperostipa comata [needle and thread], Achnatherum hymenoides [Indian ricegrass], Sporobolus airoides [alkali sacaton], and Poa secunda [Sandberg bluegrass]) from 2 areas: adjacent to and within weed invasions. Native plant species richness and …

Quantifying The Effects Of Aging On The Mechanical Properties Of Medical Grade Polycarbonate And Uv Cured Adhesives, Christopher James Lewis

Theses and Dissertations

Advances in engineering polymer technology have created a generation of high strength-to-weight materials for medical applications, with virtually no adverse interactions with body fluids. Polycarbonate is a widely used engineering polymer, and is often used in connection with ultra-violet light (UV) cured adhesives. Because of the chemical complexity of polymers, little is known about their actual aging characteristics. By characterizing the effects of aging, storage environment, and sterilization on medical grade polycarbonate/adhesive system properties, more accurate failure predictions can be made. In this thesis, efforts to better understand the effects of accelerated aging on a medical grade polycarbonate and UV …

Computing The M = 1 Diocotron Frequency Via An Equilibrium Calculation In Non-Neutral Plasmas, Ross L. Spencer

Faculty Publications

The m = 1 diocotron mode in non-neutral plasmas has long been thought of as a shifted equilibrium, and its frequency has been approximately calculated in this way by Fine and Driscoll [Phys. Plasmas 5, 601 (1998)]. This article shows that this idea can be coupled with a standard axisymmetric equilibrium calculation on a grid to calculate the frequency of this mode to very high precision including both finite-length and thermal effects, provided that the Debye length is small enough. As the Debye length begins to approach the plasma size not only does the shifted equilibrium calculation fail to predict …

Disk Based Model Checking, Tonglaga Bao

Theses and Dissertations

Disk based model checking does not receive much attention in the model checking field becasue of its costly time overhead. In this thesis, we present a new disk based algorithm that can get close to or faster verification speed than a RAM based algorithm that has enough memory to complete its verification. This algorithm also outperforms Stern and Dill's original disk based algorithm. The algorithm partitions the state space to several files, and swaps files into and out of memory during verification. Compared with the RAM only algorithm, the new algoritm reduces hash table insertion time by reducing the cost …

Optical Properties And Application Of Uranium-Based Thin Films For The Extreme Ultraviolet And Soft X-Ray Region, Richard L. Sandberg, David D. Allred, Shannon Lunt, Marie K. Urry, R. Steven Turley

Faculty Publications

Uranium oxide and uranium nitride thin films reflect significantly more than all previously known/standard reflectors (e.g., nickel, gold, and iridium) for most of the 4-10 nm range at low angles of incidence. This work includes measurements of the EUV/soft x-ray (2-20 nm) reflectance of uranium-based thin films (~20 nm thick) and extraction of their optical constants (d and ?). We report the reflectances at 5, 10, and 15 degrees grazing incidence of air-oxidized sputtered uranium, reactively sputtered (O2) uranium oxide, and reactively sputtered (N2) uranium nitride thin films measured at Beamline 6.3.2 at the Advanced Light Source (ALS) at Lawrence …

Vision-Based Human Directed Robot Guidance, Richard B. Arthur

Theses and Dissertations

This paper describes methods to track a user-defined point in the vision of a robot as it drives forward. This tracking allows a robot to keep itself directed at that point while driving so that it can get to that user-defined point. I develop and present two new multi-scale algorithms for tracking arbitrary points between two frames of video, as well as through a video sequence. The multi-scale algorithms do not use the traditional pyramid image, but instead use a data structure called an integral image (also known as a summed area table). The first algorithm uses edge-detection to track …

Variation Simulation Of Fixtured Assembly Processes For Compliant Structures Using Piecewise-Linear Analysis, Michael L. Stewart

Theses and Dissertations

While variation analysis methods for compliant assemblies are not new, little has been done to include the effects of multi-step, fixtured assembly processes. This thesis introduces a new method to statistically analyze compliant part assembly processes using fixtures. This method, consistent with the FASTA method developed at BYU, yields both a mean and a variant solution. The method, called Piecewise-Linear Elastic Analysis, or PLEA, is developed for predicting the residual stress, deformation and springback variation in compliant assemblies. A comprehensive, step-by-step analysis map is provided. PLEA is validated on a simple, laboratory assembly and a more complex, production assembly. Significant …

Analysis And Comparison Of Three Acoustic Energy Density Probes, Lance Lester Locey

Theses and Dissertations

Traditional methods for the investigation of sound fields generally rely on a microphone to convert sound pressure into an electrical signal which can be recorded, displayed, and so forth. The squared sound pressure is directly related to potential energy density. Consequently, the measurement of sound pressure alone does not inherently provide insight into the total energy density of the sound field. Specifically, no information about the kinetic energy density of the sound field is available from this measurement alone. However, it is possible to use two microphones to estimate particle velocity. The squared particle velocity magnitude is directly related to …

Information Literacy Instruction At Zhejiang University: A Case Study, Regina P. Entorf, Fred Y. Ye

Journal of East Asian Libraries

No abstract provided.

The Middle Eastern World Picture, David Richardson

Comparative Civilizations Review

No abstract provided.

Introductory Pages, Byu Studies

BYU Studies

No abstract provided.

To Journey Beyond Infinity, Kent A. Bessey

BYU Studies

The notion of infinity has fascinated philosophers, scientists, and mathematicians for millennia. Its enigmatic nature seemed to thwart all attempts to unlock its secrets. Scriptural allusions to the infinite evoke a similar sense of mystery. Few have been as intrigued by the concept of infinity—or as tenacious in trying to understand it—as the German mathematician Georg Cantor. Between 1874 and 1884, Cantor published numerous papers that illuminated some of the shadowy regions of the infinite. He discovered a remarkable realm where half of a pie is as large as the whole, infinity comes in different sizes, and miracles are mathematically …

To Depict Infinity: The Artwork Of Wulf Barsch, Wulf Barsch

BYU Studies

No abstract provided.

Index, Byu Studies, Byu Studies

BYU Studies

No abstract provided.

Lee Daniel Snyder. Macro History: A Theoretical Approach To Comparative World History, Laurence Grambow Wolf

Comparative Civilizations Review

No abstract provided.

Network-Layer Selective Security, Casey T. Deccio

Theses and Dissertations

The Internet and other large computer networks have become an integral part of numerous daily processes. Security at the network layer is necessary to maintain infrastructure survivability in the case of cyber attacks aimed at routing protocols. In order to minimize undesired overhead associated with added security at this level, the notion of selective security is proposed. This thesis identifies elements in network topologies that are most important to the survivability of the network. The results show that the strategic placement of network security at critical elements will improve overall network survivability without the necessity of universal deployment.

The Benefit Of Using Simulation To Improve The Implementation Of Lean Manufacturing Case Study: Quick Changeovers To Allow Level Loading Of The Assembly Line, Jack J. Mcclellan

Theses and Dissertations

In today's competitive manufacturing environment, companies are constantly looking for ways to improve. Because of this, many companies are striving to become "lean" by implementing lean manufacturing, which is a difficult process. To aid in the implementation of lean manufacturing, simulation was used to reduce the trial-and-error period of lean manufacturing and find to optimum approach to implement the lean manufacturing principle. In this research, a case study of implementing level loading of the production schedule for BullFrog International, L.C. will be examined. To make it possible to implement level loading, the thermo-former machine at the beginning of the operations …

A Review Of Setup Practices And Procedures For Creating Ieee 802.11 Wireless Community Networks, Jae M. Theobald

Theses and Dissertations

IEEE 802.11 wireless networking equipment has made it possible to bridge the last mile for new broadband internet service providers. Inexpensive wireless networking equipment and high gain antennas enable high speed internet delivery at a fraction of the cost of installing or upgrading land lines for cable or DSL services. Based on this research, a guide of general practices and procedures is proposed for designing, installing, and maintaining a reliable wireless community area network. Included tests have provided performance results for several types of wireless antennas (including wire grid parabolic dishes, Yagi and Vagi styles, and echo backfire), wireless bridges, …

Numerical Simulations In Electro-Osmotic Flow, Joseph S. Tenny

Theses and Dissertations

The developing flow field in a parallel plate microchannel, induced by wall motion, has been modeled numerically. This type of flow simulates the physical driving mechanism that exists in electro-osmotically generated flow with large channel diameter-to-Debye length ratios (Z). The physics of the flow field were compared between the moving wall model (MWM) and electro-osmotic flow (EOF) at Reynolds numbers of 1 and 1800, and Z > 2500. Also, Z-values between 50 and 500 were studied to investigate the accuracy of the MWM. Results show that for Z-values greater than 100 the MWM shows good agreement with EOF.

The dynamics of …

Rapid And Convenient Method For Preparing Masters For Microcontact Printing With 1–12 Μm Features, Lloyd W. Zilch, Ghaleb A. Husseini, Yit-Yian Lua, Michael V. Lee, Kevin R. Gertsch, Bennion R. Cannon, Robert M. Perry, Eric T. Sevy, Matthew C. Asplund, Adam T. Woolley, Matthew R. Linford

Faculty Publications

Mechanical scribing can be employed to create surfaces with recessed features. Through replica molding elastomeric copies of these scribed surfaces are created that function as stamps for microcontact printing. It is shown that this new method for creating masters for microcontact printing can be performed with a computer-controlled milling machine (CNC), making this method particularly straightforward and accessible to a large technical community that does not need to work in a particle free environment. Thus, no clean room, or other specialized equipment is required, as is commonly needed to prepare masters. Time-of-flight secondary ion mass spectrometry confirms surface pattering by …

Evidence Of Linear Lattice Expansion And Covalency Enhancement In Rutile Tio2 Nanocrystals, Guangshe Li, Juliana Boerio-Goates, Brian F. Woodfield, Liping Li

Faculty Publications

Lattice variations and bonding characteristics in rutile TiO2 nanocrystals were examined by x-ray diffraction and x-ray photoelectron spectroscopy. With a reduction in the physical dimensions, rutile TiO2 nanocrystals show a linear lattice expansion and an anomalous covalency enhancement in apparent contradiction to the ionicity increase in BaTiO3 and CuO nanocrystals as reported recently by S. Tsunekawa et al. [Phys. Rev. Lett. 2000, 85, 3440] and V. R. Palkar et al. [Phys. Rev. B 1996, 53, 2167]. A surface defect dipole model is proposed to explain these physical phenomena in terms of the strong interactions among the surface dipoles that produce …

Our Legacy Of Religious Education, Stephen K. Iba

Religious Educator: Perspectives on the Restored Gospel

From a talk given at the CES Area Directors Convention, September 27, 1997.

When And How Trustworthiness Matters: Knowledge Transfer And The Moderating Effect Of Causal Ambiguity, Robert J. Jensen, Gabriel Szulanski, Rossella Cappetta

Faculty Publications

The recognition that better use of existing internal knowledge could enhance survival chances or organizations has spawned substantial interest in the transferability of routinized, experiential learning to additional settings within the organization Previous research has established that trustworthiness of the source enhances such knowledge transfer. More recent work, however, suggests that this may not always be the case. Yet, little systematic attention has been paid to moderating conditions. The major purpose of this paper is to identify a moderator, causal ambiguity, which delineates the conditions as to when and how a recipient's perception of the trustworthiness of a source affects …

Jumpstarting Phylogenetic Analysis, Mark J. Clement, Keith A. Crandall, Kevin Seppi, Quinn O. Snell

Faculty Publications

When a new epidemic strikes, it is often important to determine the relationship between the current organism and others that have been successfully treated previously. The phylogenetic analysis problem generates the most likely family tree for a group of organisms based on DNA sequence data. This process can take a prohibitively long period of time with current algorithms. If trees resulting from prior searches are used to seed the search, correct trees can be found much more quickly. This jumpstarting algorithm can generate superior phylogenetic solutions much more quickly than existing algorithms.

An Ecological Display For Robot Teleoperation, Robert W. Ricks

Theses and Dissertations

This thesis presents an interface for effectively teleoperating robots that combines an ecological display of range and video information with quickening based on dead-reckoning prediction. This display is built by viewing range and video information from a virtual camera trailing the robot. This is rendered in 3-D by using standard hardware acceleration and 3-D graphics software. Our studies demonstrate that this interface improves performance for most people, including those that do not have much previous experience with robotics. These studies involved 32 test subjects in a simulated environment and 8 in the real world. Subjects were required to drive the …