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Vegetation Response To Prescribed Fire In Dinosaur National Monument, Barry L. Perryman, Richard A. Olson, Stephen Petersburg, Tamara Naumann Oct 2002

Vegetation Response To Prescribed Fire In Dinosaur National Monument, Barry L. Perryman, Richard A. Olson, Stephen Petersburg, Tamara Naumann

Western North American Naturalist

Much of western North America is dominated by dense, monotypic, late seral stands of big sagebrush (Artemisia tridentata Nutt.). These stands often have depauperate understories with limited species richness, diversity, and herbaceous cover. The National Park Service at Dinosaur National Monument, Colorado, is using both strategic and natural prescribed fire in Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis Beetle and Young) communities to foster intra-community (α-scale) and landscape diversity. This study analyzed an accumulated foliar cover data set between paired burn and control areas on 6 different sites during the last 20 years. Across the monitoring period, mean …

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Geographic Variation In Pelage Color Of Piñon Mice (Peromyscus Truei) In The Northern Great Basin And Environs, Leslie N. Carraway, B. J. Verts Oct 2002

Geographic Variation In Pelage Color Of Piñon Mice (Peromyscus Truei) In The Northern Great Basin And Environs, Leslie N. Carraway, B. J. Verts

Western North American Naturalist

Cluster analyses of values for hue, value, and chroma (based on Munsell soil-color charts) obtained at 6 points on pelages of 202 adult piñon mice (Peromyscus truei) from the northern Great Basin and environs produced dendrograms with specimens grouped into 5 clusters. In most instances distribution of specimens forming clusters reflected those published for nominal races. In instances in which previous distributions of nominal races were not supported and for specimens previously unclassified, geographic distribution of groups of color morphs was logical and suggested avenues for additional research on geographic variation in the species.

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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 …

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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.

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What Is Living And What Is Dead In Eurocentrism?, Ricardo Duchesne Oct 2002

What Is Living And What Is Dead In Eurocentrism?, Ricardo Duchesne

Comparative Civilizations Review

No abstract provided.

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Performance Evaluation Of Path Searching Heuristics For Multicast Qos Routing, Daniel Zappala, Dayi Zhou Oct 2002

Performance Evaluation Of Path Searching Heuristics For Multicast Qos Routing, Daniel Zappala, Dayi Zhou

Faculty Publications

Quality of Service routing for multicast enables a group member to find and install a branch of the multicast tree that can meet its QoS constraints. The most promising protocols in this area use receiver-oriented path searching heuristics to find feasible routes. In this paper, we examine the performance of the path searching heuristics used by these protocols, to determine which techniques are the most effective. We find that several low-overhead path searching heuristics are effective, and that generic path searching can work as well as targeted, QoS-specific searching.

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Globalization As A Signal Of The Next Stage In Cultural Evolution, Lee Stauffer Oct 2002

Globalization As A Signal Of The Next Stage In Cultural Evolution, Lee Stauffer

Comparative Civilizations Review

No abstract provided.

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Compact Focusing Von Hamos Spectrometer For Quantitative X-Ray Spectroscopy, Larry V. Knight, A. P. Shevelko, Yu S. Kasyanov, O. F. Yakushev Oct 2002

Compact Focusing Von Hamos Spectrometer For Quantitative X-Ray Spectroscopy, Larry V. Knight, A. P. Shevelko, Yu S. Kasyanov, O. F. Yakushev

Faculty Publications

A compact focusing crystal spectrometer based on the von Hamos scheme is described. Cylindrically curved mica and graphite crystals with a radius of curvature of R = 20 mm are used in the spectrometer. A front illuminated charge-coupled device (CCD) linear array detector makes this spectrometer useful for real-time spectroscopy of laser-produced plasma x-ray sources within the wavelength range of lambda= 1.8-10 Angstroms. Calibration of crystals and the CCD linear array makes it possible to measure absolute photon fluxes. X-ray spectra in an absolute intensity scale were obtained from Mg, Ti, and Fe laser-produced plasmas, with a spectral resolution lambda/delta …

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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 …

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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.

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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.

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“Those Who See”: A Century's Charge To Religious Educators, Scott C. Esplin, Brent R. Esplin Sep 2002

“Those Who See”: A Century's Charge To Religious Educators, Scott C. Esplin, Brent R. Esplin

Religious Educator: Perspectives on the Restored Gospel

No abstract provided.

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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 …

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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.

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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.

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Construction And Testing Of A Low-Finesse Fabry-Perot Interferometer For Use In Atomic Spectroscopy, Nathan C. Moody Aug 2002

Construction And Testing Of A Low-Finesse Fabry-Perot Interferometer For Use In Atomic Spectroscopy, Nathan C. Moody

Student Works

I built a low-finesse confocal cavity with aluminum mirrors for use in the imaging of ultra-cold calcium ion plasmas. The confocal cavity provides stability at large mirror separations, a condition necessary for achieving both low finesse and narrow peak widths. Additionally, the finesse in the case of coherent input is effectively doubled compared to multi-mode resonance. The cavity was tested using a GaN diode laser input at 397nm. The transmission obtained indicated that the finesse of the cavity was slightly lower than the prediction based on measurements of the mirror reflectivities and the assumption of incoherent input.

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A Formal Method To Analyze Framework-Based Software, Trent N. Larson Aug 2002

A Formal Method To Analyze Framework-Based Software, Trent N. Larson

Theses and Dissertations

Software systems are frequently designed using abstractions that make software verification tractable. Specifically, by choosing meaningful, formal abstractions for interfaces and then designing according to those interfaces, one can verify entire systems according to behavioral predicates. While impractical for systems in general, framework-based software architectures are a type of system for which formal analysis can be beneficial and practical over the life of the system. We present a method to formally analyze behavioral properties of framework-based software with higher-order logic and then demonstrate its utility for a significant, modern system.

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Simulations Of The Instability Of The M = 1 Self-Shielding Diocotron Mode In Finite-Length Non-Neutral Plasmas, Grant W. Mason, Ross L. Spencer Aug 2002

Simulations Of The Instability Of The M = 1 Self-Shielding Diocotron Mode In Finite-Length Non-Neutral Plasmas, Grant W. Mason, Ross L. Spencer

Faculty Publications

The "self-shielding" m = 1 diocotron mode in Malmberg-Penning traps has been known for over a decade to be unstable for finite length non-neutral plasmas with hollow density profiles. Early theoretical efforts were unsuccessful in accounting for the exponential growth and/or the magnitude of the growth rate. Recent theoretical work has sought to resolve the discrepancy either as a consequence of the shape of the plasma ends or as a kinetic effect resulting from a modified distribution function as a consequence of the protocol used to form the hollow profiles in experiments. Both of these finite length mechanisms have been …

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Diet And Food-Niche Breadth Of Burrowing Owls (Athene Cunicularia) In The Imperial Valley, California, Melissa M. York, Daniel K. Rosenberg, Ken K. Sturm Jul 2002

Diet And Food-Niche Breadth Of Burrowing Owls (Athene Cunicularia) In The Imperial Valley, California, Melissa M. York, Daniel K. Rosenberg, Ken K. Sturm

Western North American Naturalist

Burrowing Owls (Athene cunicularia) occupy intensively managed agricultural areas within the Imperial Valley of California, where they occur at high densities relative to other areas in the state, and yet reproductive rates are often low. Understanding diet and food-niche breadth may lead to insights into factors contributing to their poor reproductive performance. We tested the relative contribution of sex, year, and season on diet composition and food-niche breadth from analyses of stomach contents of adult Burrowing Owls (n = 53). Orthoptera dominated the diet; it accounted for 58.9% of the total number of prey items in all …

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Modeling The Effects Of Greenbelts At The Urban-Rural Fringe, Daniel G. Brown, S. E. Page, Rick L. Riolo, William Rand Jul 2002

Modeling The Effects Of Greenbelts At The Urban-Rural Fringe, Daniel G. Brown, S. E. Page, Rick L. Riolo, William Rand

International Congress on Environmental Modelling and Software

We present and evaluate an agent based model (ABM) of land use change at the rural-urban fringe, comparing its performance to a mathematical model of the same process. Our simplified model was developed in Swarm using agents with heterogeneous preferences and a landscape with heterogeneous properties. The context of this work is a larger project that includes surveys of the preferences of residents and data on historical patterns of development. Our broader goal is to use the model to evaluate the ecological effects of alternative policies and designs. We begin by evaluating the influence of a greenbelt, which is located …

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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 …

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Indirect Effects In Ecosystems: A Review Of Recent Modelling Studies And A Methodological Framework For Comparative Theoretical Analysis, V. Krivtsov Jul 2002

Indirect Effects In Ecosystems: A Review Of Recent Modelling Studies And A Methodological Framework For Comparative Theoretical Analysis, V. Krivtsov

International Congress on Environmental Modelling and Software

Indirect interrelations between ecosystem processes are often realised after a considerable time lag,and, therefore, are easily overlooked. The understanding of these relationships, however, is indispensable forsustainable development and ecomanagement. Investigation of mechanisms underpinning complex indirectdelayed relationships is greatly aided by advanced mathematical techniques, including correlation, multipleregression and factor analysis, simulation modelling, etc. This paper provides a brief review of the recentrelevant studies. These techniques may be especially useful if used in concert on a range of ecosystems, thusintegrating the information obtained in a comparative theoretical ecosystem analysis (CTEA). Amethodological framework for CTEA is given and possible implications discussed.

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Georef: A Software For Improving The Use Of Remote Sensing Images In Environmental Applications, D. Carrion, M. Gianinetto, M. Scaioni Jul 2002

Georef: A Software For Improving The Use Of Remote Sensing Images In Environmental Applications, D. Carrion, M. Gianinetto, M. Scaioni

International Congress on Environmental Modelling and Software

Analysis of temporal sequences of satellite images is of great importance in the monitoring ofenvironmental phenomena, where both multi-temporal and multi-spectral images are widely used. The firstproblem to deal with such a kind of imagery is their geo-referencing, i.e. computing a transformation to ageodetic or cartographic datum. This task is usually performed by manually measuring control points, whoseground coordinates are read on existing maps or measured by GPS. In this paper we propose a software(GEOREF) to increase the automation of this procedure, which is very heavy for the operators in the RemoteSensing field. Considering a multi-temporal sequence of satellite images, …

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Spasim: A Software To Simulate Cellular Automata Models, Niandry Moreno, Magdiel Ablan, Giorgio Tonella Jul 2002

Spasim: A Software To Simulate Cellular Automata Models, Niandry Moreno, Magdiel Ablan, Giorgio Tonella

International Congress on Environmental Modelling and Software

Simulation models are a key tool to study the dynamics of ecological systems where space plays a fundamental role. These kinds of models in which the dynamic of the system is space-dependent are called spatial simulation models. The most frequently used approach to simulate spatial models consists of a simulation program (typically developed in a general purposed language) that periodically exports results to a Geographic Information System (GIS) to visualize or analyze the spatial component. This type of approach requires of a user programming skills and to be knowledgeable about GIS, limiting the use of the model and increasing the …

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Renewable Energy: A Decision Support System For Forest Biomass Exploitation, D. Freppaz, R. Minciardi, M. Robba, Roberto Sacile, A. Taramasso Jul 2002

Renewable Energy: A Decision Support System For Forest Biomass Exploitation, D. Freppaz, R. Minciardi, M. Robba, Roberto Sacile, A. Taramasso

International Congress on Environmental Modelling and Software

A decision support system for forest biomass exploitation for energy supply is presented. In the proposed approach, geographic information system based techniques are integrated with mathematical programming methods yielding a comprehensive system, which allows formalizing the problem, taking decisions, and evaluating their effects. The aim of this work is to evaluate the possibility of biomass exploitation for both thermal and electric energy production in a provincial area. The decision support system is able to locate and size different kinds of plants on the territory (defining which kind of energy is convenient to produce for the specific area), take into account …

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Exergy And Information Indices: A Comparison For Use In Structurally Dynamic Models, Brian D. Fath Jul 2002

Exergy And Information Indices: A Comparison For Use In Structurally Dynamic Models, Brian D. Fath

International Congress on Environmental Modelling and Software

Ecosystems are open, dynamic systems changing both their structure and their function over time. A model, which is an abstraction of the system manifest at the time of its construction, can project future dynamics so long as the fundamental structure of the system does not change. A primary modelling challenge arises when the system structure changes, i.e., internal reorganization, as a result of external perturbation. Ideally, one could include algorithms in the model to anticipate such changes, but that would entail knowing a great deal more about the system and disturbances to it than is possible. Other methods to anticipate, …

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Evaluating Agricultural Systems For Environmental Sustainability Using An Impact Matrix Approach, James C. Ascough Ii, D.L. Hoag, Alejandra Engler-Palma Jul 2002

Evaluating Agricultural Systems For Environmental Sustainability Using An Impact Matrix Approach, James C. Ascough Ii, D.L. Hoag, Alejandra Engler-Palma

International Congress on Environmental Modelling and Software

Sustainable agriculture is a complex problem that demands consideration of many interrelated factors, processes, and institutions. Unfortunately, current definitions of sustainability are expansive, and use as a guide for strategic planning or decision making is clouded by ambiguity and a plethora of definitions. Regardless of how sustainability is defined, agricultural producers are interested in developing and evaluating agricultural management systems that are both environmentally sound and economically profitable. There has been a proliferation of decision analysis and economic indicator tools developed to aid producers; however, the tools rarely are used due to excessive complexity or a failure to capture important …

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Lpv Approximation Of Distributed Parameter Systems In Environmental Modeling, G. Belforte, F. Dabbene, P. Gay Jul 2002

Lpv Approximation Of Distributed Parameter Systems In Environmental Modeling, G. Belforte, F. Dabbene, P. Gay

International Congress on Environmental Modelling and Software

Environmental systems often involve phenomena that are continuous functions not only of time, but also of other independent variables, such as space coordinates. Typical examples are transportation phenomena of mass or energy, such as heat transmission and/or exchange, humidity diffusion or concentration distributions. These systems are intrinsically distributed parameter systems whose description usually requires the introduction of partial differential equations (PDE). Therefore, their modeling can be quite complex, both for what concerns the model construction and its identification. Indeed, a typical approach for the simulation of such systems is the use of finite element techniques. However, this kind of description …

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A Dss For Water Resources Management Under Uncertainty, Stefano Pallottino, Giovanni M. Sechi, Paola Zuddas Jul 2002

A Dss For Water Resources Management Under Uncertainty, Stefano Pallottino, Giovanni M. Sechi, Paola Zuddas

International Congress on Environmental Modelling and Software

In this paper we present a scenario analysis approach to perform water system planning andmanagement under climatic and hydrological uncertainty. A DSS with a a graphical interface allows the user afriendly data-input phase and results analysis.Different generation techniques can be used to set up and analyze a number of scenarios. Uncertainty ismodeled by a scenario-tree in a multistage environment, which includes different possible configurations ofinflows in a wide time-horizon. The aim is to identify trends and essential features on which to base a robustdecision policy.The DSS prevent obsolescence of optimizer codes exploiting the standard input format MPS. Obtained resultsshow that …

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Population Dynamics And Treatment Strategies Of Phytophthora Infestans (Late Blight) In The Mid-Hills Of Nepal, Heico Apel, M. S. Paudyal, O. Richter Jul 2002

Population Dynamics And Treatment Strategies Of Phytophthora Infestans (Late Blight) In The Mid-Hills Of Nepal, Heico Apel, M. S. Paudyal, O. Richter

International Congress on Environmental Modelling and Software

The fungus Phytophthora infestans is a major ubiquitous pest in solanaceous crops and causes great damages in the agricultural systems in Nepal. This is especially true in the cash crop orientated areas of the Mid-Hills and the Terai region, where potato and tomato cropping is a prominent income source of the rural population. This fact in combination with cheap and readily available pesticides is responsible for the frequent and perceived over-use of chemical plant protection agents. Based on this background a series of agronomic field trials in the Jhikhu-Khola watershed aiming at the optimisation of P. infestans treatment strategy was …

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