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2008

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Variation Of The Martian Ionospheric Electron Density From Mars Express Radar Soundings, D. D. Morgan, D. A. Gurnett, D. L. Kirchner, Jane L. Fox, E. Nielsen, J. J. Plaut Sep 2008

Variation Of The Martian Ionospheric Electron Density From Mars Express Radar Soundings, D. D. Morgan, D. A. Gurnett, D. L. Kirchner, Jane L. Fox, E. Nielsen, J. J. Plaut

Physics Faculty Publications

The Mars Advanced Radar for Subsurface and Ionospheric Sounding aboard Mars Express has been in operation for over 2 years. Between 14 August 2005 and 31 July 2007, we obtain 34,492 ionospheric traces, of which 14,060 yield electron density profiles and 12,291 yield acceptable fits to the Chapman ionospheric model. These results are used to study the Martian ionosphere under changing conditions: the presence or absence of solar energetic particles, solar EUV flux, season, solar zenith angle, and latitude. The 2-year average subsolar maximum electron density n 0 is 1.62 × 105 cm−3, the average subsolar electron …


Surface Traps In Vapor-Phase-Grown Bulk Zno Studied By Deep Level Transient Spectroscopy, Z-Q. Fang, B. Claflin, David C. Look, Y. F. Dong, H. L. Mosbacker, L. J. Brillson Sep 2008

Surface Traps In Vapor-Phase-Grown Bulk Zno Studied By Deep Level Transient Spectroscopy, Z-Q. Fang, B. Claflin, David C. Look, Y. F. Dong, H. L. Mosbacker, L. J. Brillson

Physics Faculty Publications

Deep level transient spectroscopy, current-voltage, and capacitance-voltage measurements are used to study interface traps in metal-on-bulk-ZnO Schottky barrier diodes (SBDs). c-axis-oriented ZnO samples were cut from two different vapor-phase-grown crystals, and Au- and Pd-SBDs were formed on their (0001) surfaces after remote oxygen-plasma treatment. As compared to Au-SBDs, the Pd-SBDs demonstrated higher reverse-bias leakage current and forward-bias current evidently due to higher carrier concentrations, which might have been caused by hydrogen in-diffusion through the thin Pd metal. The dominant traps included the well-known bulk traps E3 (0.27 eV) and E4 (0.49 eV). In addition, a surface-related trap, …


Active And Passive Imaging In The Thz Spectral Region: Phenomenology, Dynamic Range, Modes, And Illumination, Douglas T. Petkie, Corey Casto, Frank C. De Lucia, Steven R. Murrill, Brian Redman, Richard L. Espinola, Charmaine C. Franck, Eddie L. Jacobs, Steven T. Griffin, Carl E. Halford, Joe Reynolds, Sean O'Brien, David Tofsted Sep 2008

Active And Passive Imaging In The Thz Spectral Region: Phenomenology, Dynamic Range, Modes, And Illumination, Douglas T. Petkie, Corey Casto, Frank C. De Lucia, Steven R. Murrill, Brian Redman, Richard L. Espinola, Charmaine C. Franck, Eddie L. Jacobs, Steven T. Griffin, Carl E. Halford, Joe Reynolds, Sean O'Brien, David Tofsted

Physics Faculty Publications

The useful compromise between resolution and penetration power of the submillimeter or terahertz (THz) spectral region has long made it attractive for a variety of imaging applications. However, many of the demonstrations of imaging in this spectral region have used strategically oriented targets, especially favorable concealment materials, proximate imaging geometries, etc. This paper reports the results of studies aimed at better understanding the phenomenology of targets, the impact of this phenomenology on various active and passive imaging strategies, and most importantly, the development of imaging strategies that do not require the aforementioned special circumstances. Particular attention is paid to the …


The Science Education Of American Girls: A Historical Perspective, By Kim Tolley, William Watson Sep 2008

The Science Education Of American Girls: A Historical Perspective, By Kim Tolley, William Watson

Journal of Catholic Education

No abstract provided.


2008 Grizzly Football Yearbook, University Of Montana--Missoula. Athletics Department Sep 2008

2008 Grizzly Football Yearbook, University Of Montana--Missoula. Athletics Department

Grizzly Football Yearbook, 1939-2018

Annual yearbook of the University of Montana’s Athletics Department. This volume covers the period from fall 2008 through spring 2009.


Two-Layer Hall-Effect Model With Arbitrary Surface-Donor Profiles: Application To Zno, David C. Look Sep 2008

Two-Layer Hall-Effect Model With Arbitrary Surface-Donor Profiles: Application To Zno, David C. Look

Physics Faculty Publications

A complete two-layer Hall-effect model, allowing arbitrary donor and acceptor profiles, is presented and applied to the problem of conductive surface layers in ZnO. Temperature-dependent mobility and carrier concentration data in the temperature range of 20–320 K are fitted with an efficient algorithm easily implemented in commercial mathematics programs such as MATHCAD. The model is applied to two ZnO samples, grown by the melt (MLT) and hydrothermal (HYD) processes, respectively. Under the assumption of a “square” surface-donor profile, the fitted surface-layer thicknesses are 48 and 2.5 nm, respectively, for the MLT and HYD samples. The surface-donor concentrations are 7.6×1017 …


Inhibition Of Linear Absorption In Opaque Materials Using Phase-Locked Harmonic Generation, Marco Centini, Vito Roppo, Eugenio Fazio, Federico Pettazzi, Concita Sibilia, Joseph W. Haus, John V. Foreman, Neset Akozbek, Mark J. Bloemer, Michael Scalora Sep 2008

Inhibition Of Linear Absorption In Opaque Materials Using Phase-Locked Harmonic Generation, Marco Centini, Vito Roppo, Eugenio Fazio, Federico Pettazzi, Concita Sibilia, Joseph W. Haus, John V. Foreman, Neset Akozbek, Mark J. Bloemer, Michael Scalora

Electrical and Computer Engineering Faculty Publications

We theoretically predict and experimentally demonstrate inhibition of linear absorption for phase and group velocity mismatched second- and third-harmonic generation in strongly absorbing materials, GaAs, in particular, at frequencies above the absorption edge.

A 100-fs pump pulse tuned to 1300 nm generates 650 and 435 nm second- and third-harmonic pulses that propagate across a 450−μm-thick GaAs substrate without being absorbed.

We attribute this to a phase-locking mechanism that causes the pump to trap the harmonics and to impress on them its dispersive properties.


Evidence Of Ancient Writing On Metal: An Interview With H. Curtis Wright, H. Curits Wright, Elisabeth R. Sutton Sep 2008

Evidence Of Ancient Writing On Metal: An Interview With H. Curtis Wright, H. Curits Wright, Elisabeth R. Sutton

Religious Educator: Perspectives on the Restored Gospel

No abstract provided.


Orthodontic Mini-Implant Failure: Assessing The Relationship To Bone Quality Using Qcbct, Joshua Schneider Sep 2008

Orthodontic Mini-Implant Failure: Assessing The Relationship To Bone Quality Using Qcbct, Joshua Schneider

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to evaluate the cortical bone thickness (mm), cortical bone density (HU), and trabecular bone density (HU) of mini-implants sites in both the maxilla and mandible using QCBCT to determine if they had any effect on mini-implant failure rate. Patient characteristics (age, gender, facial type), mini-implant characteristics (date of placement, manufacturer, length, and diameter), and the mini-implant site (region) were also evaluated. One hundred and six mini-implants in 50 consecutive patients with complete patient records, CBCT information, and T1 radiographs were included in the study. Thirty-four of the 106 mini-implants were considered "failures" resulting in …


Uah Student Handbook 2008-2010, University Of Alabama In Huntsville Sep 2008

Uah Student Handbook 2008-2010, University Of Alabama In Huntsville

Student Handbooks

No abstract provided.


Rejuvenate Pointcut: A Tool For Pointcut Expression Recovery In Evolving Aspect-Oriented Software, Raffi Khatchadourian, Awais Rashid Sep 2008

Rejuvenate Pointcut: A Tool For Pointcut Expression Recovery In Evolving Aspect-Oriented Software, Raffi Khatchadourian, Awais Rashid

Publications and Research

Aspect-oriented programming (AOP) strives to localize the scattered and tangled implementations of crosscutting concerns (CCCs) by allowing developers to declare that certain actions (advice) should be taken at specific points (join points) during the execution of software where a CCC (an aspect) is applicable. However, it is non-trivial to construct optimal pointcut expressions (a collection of join points) that capture the true intentions of the programmer and, upon evolution, maintain these intentions. We demonstrate an AspectJ source-level inferencing tool called rejuvenate pointcut which helps developers maintain pointcut expressions over the lifetime of a software product. A key insight into the …


Diffusion Models For Animals In Complex Landscapes: Incorporating Heterogeneity Among Substrates, Individuals And Edge Behaviours, John D. Reeve, James T. Cronin, Kyle J. Haynes Sep 2008

Diffusion Models For Animals In Complex Landscapes: Incorporating Heterogeneity Among Substrates, Individuals And Edge Behaviours, John D. Reeve, James T. Cronin, Kyle J. Haynes

Faculty Publications

1. Animals move commonly through a variety of landscape elements and edges in search of food, mates and other resources. We developed a diffusion model for the movement of an insect herbivore, the planthopper Prokelisia crocea, that inhabits a landscape composed of patches of its host plant, prairie cordgrass Spartina pectinata, embedded in a matrix of mudflat or smooth brome Bromus inermis. 2. We used mark-release-resight experiments to quantify planthopper movements within cordgrass-brome and cordgrass-mudflat arenas. A diffusion model was then fitted that included varying diffusion rates for cordgrass and matrix, edge behaviour in the form of a biased random …


Financial Control Of A Competitive Economy Without Randomness, Ioannis Karatzas, Martin Shubik, William D. Sudderth Sep 2008

Financial Control Of A Competitive Economy Without Randomness, Ioannis Karatzas, Martin Shubik, William D. Sudderth

Cowles Foundation Discussion Papers

The monetary and fiscal control of a simple economy without outside randomness is studied here from the micro-economic basis of a strategic market game. The government’s bureaucracy is treated as a public good that provides services at a cost. A conventional public good is also considered.


The Value Of Fiat Money With An Outside Bank: An Experimental Game, Juergen Huber, Martin Shubik, Shyam Sunder Sep 2008

The Value Of Fiat Money With An Outside Bank: An Experimental Game, Juergen Huber, Martin Shubik, Shyam Sunder

Cowles Foundation Discussion Papers

Why people accept intrinsically worthless fiat money in exchange for real goods and services has been a longstanding question. There are many competing sufficient explanations that may confound each other in practice but can be individually tested in isolation experimentally. In this paper we examine a sufficient explanation of the value of fiat money through the existence of a debt instrument which allows consumption to be moved earlier in time. We present experimental evidence that the theoretical predictions about the behavior of such economies work reasonably well in a laboratory setting. The import of this finding for the theory of …


Sufficiency Of An Outside Bank And A Default Penalty To Support The Value Of Fiat Money: Experimental Evidence, Juergen Huber, Martin Shubik, Shyam Sunder Sep 2008

Sufficiency Of An Outside Bank And A Default Penalty To Support The Value Of Fiat Money: Experimental Evidence, Juergen Huber, Martin Shubik, Shyam Sunder

Cowles Foundation Discussion Papers

We present a model in which an outside bank and a default penalty support the value of fiat money, and experimental evidence that the theoretical predictions about the behavior of such economies, based on the Fisher-condition, work reasonably well in a laboratory setting. The import of this finding for the theory of money is to show that the presence of a societal bank and default laws provide sufficient structure to support the use of fiat money and use of the bank rate to influence inflation or deflation, although other institutions could provide alternatives.


Innovation And Equilibrium?, Martin Shubik Sep 2008

Innovation And Equilibrium?, Martin Shubik

Cowles Foundation Discussion Papers

A discussion is given of the problems involved in the formal modeling of the innovation process. The link between innovation and finance is stressed. The nature of how the circular flow of funds is broken and the role of finance in evaluation and control is discussed.


Gsi: Geo Scene Investigation! On-Site Programming (Grade 7), Discover Mojave: Forever Earth Sep 2008

Gsi: Geo Scene Investigation! On-Site Programming (Grade 7), Discover Mojave: Forever Earth

Curriculum materials (FE)

GSI: Geo Scene Investigation! introduces students to the differences between observations and interpretations and to some of the fundamental principles of geology. Students identify specific geologic processes and landforms in the landscape surrounding them at Lake Mead National Recreation Area (NRA) by solving mysteries with a set of geology-related clues.


Gambel Oak Growth Forms: Management Opportunities For Increasing Ecosystem Diversity, Scott R. Abella Sep 2008

Gambel Oak Growth Forms: Management Opportunities For Increasing Ecosystem Diversity, Scott R. Abella

Public Policy and Leadership Faculty Research

Gambel oak (Quercus gambelii) clones have several different growth forms in southwestern ponderosa pine (Pinus ponderosa) forests, and these growth forms each provide unique wildlife habitat and resource values. The purposes of this note are to review published growth-form classifications for Gambel oak, provide examples of ecological effects of different growth forms, and summarize management strategies for promoting desired growth forms. Four different growth-form classifications have been published, which generally recognize variants of three basic forms: shrubby thickets of small-diameter stems, pole-sized clumps, and large trees. These growth forms exemplify ecological and management tradeoffs. For example, shrubby forms provide browse …


Changes In Gambel Oak Densities In Southwestern Ponderosa Pine Forests Since Euro-American Settlement, Scott R. Abella, Peter Z. Fule Sep 2008

Changes In Gambel Oak Densities In Southwestern Ponderosa Pine Forests Since Euro-American Settlement, Scott R. Abella, Peter Z. Fule

Public Policy and Leadership Faculty Research

Densities of small-diameter ponderosa pine (Pinus ponderosa) trees have increased in southwestern ponderosa pine forests during a period of fire exclusion since Euro-American settlement in the late 1800s. However, less well known are potential changes in Gambel oak (Quercus gambelii) densities during this period in these forests. We reviewed published literature to summarize changes in oak density in ponderosa pine forests over the past 140 years and evaluated the possibility that large-diameter oaks have decreased in density. All nine studies examining oak density changes found that densities of small-diameter oaks have escalated. Increases ranged from 4- to more than 63-fold. …


Estimating Soil Seed Bank Characteristics In Ponderosa Pine Forests Using Vegetation And Forest-Floor Data, Scott R. Abella, Judith D. Springer Sep 2008

Estimating Soil Seed Bank Characteristics In Ponderosa Pine Forests Using Vegetation And Forest-Floor Data, Scott R. Abella, Judith D. Springer

Public Policy and Leadership Faculty Research

Soil seed banks are important for vegetation management because they contain propagules of species that may be considered desirable or undesirable for site colonization after management and disturbance events. Knowledge of seed bank size and composition before planning management activities facilitates proactive management by providing early alerts of exotic species presence and of abilities of seed banks to promote colonization by desirable species. We developed models in ponderosa pine (Pinus ponderosa) forests in northern Arizona to estimate the size and richness of mineral soil seed banks using readily observable vegetation and forestfloor characteristics. Regression models using three or fewer predictors …


Tetrahymena Thermophila And Candida Albicans Group I Intron-Derived Ribozymes Can Catalyze The Trans-Excision-Splicing Reaction, P. Patrick Dotson Ii, Ashley K. Johnson, Stephen M. Testa Sep 2008

Tetrahymena Thermophila And Candida Albicans Group I Intron-Derived Ribozymes Can Catalyze The Trans-Excision-Splicing Reaction, P. Patrick Dotson Ii, Ashley K. Johnson, Stephen M. Testa

Chemistry Faculty Publications

Group I intron-derived ribozymes can catalyze a variety of non-native reactions. For the trans-excision-splicing (TES) reaction, an intron-derived ribozyme from the opportunistic pathogen Pneumocystis carinii catalyzes the excision of a predefined region from within an RNA substrate with subsequent ligation of the flanking regions. To establish TES as a general ribozyme-mediated reaction, intron-derived ribozymes from Tetrahymena thermophila and Candida albicans, which are similar to but not the same as that from Pneumocystis, were investigated for their propensity to catalyze the TES reaction. We now report that the Tetrahymena and Candida ribozymes can catalyze the excision of a …


Inside Unlv, Diane Russell, Shane Bevell, Michelle Mouton, Erin O'Donnell, Mamie Peers, Grace Russell, Deana Waddell Sep 2008

Inside Unlv, Diane Russell, Shane Bevell, Michelle Mouton, Erin O'Donnell, Mamie Peers, Grace Russell, Deana Waddell

Inside UNLV

No abstract provided.


Associated Varieties And Howe's N-Spectrum, Hongyu He Sep 2008

Associated Varieties And Howe's N-Spectrum, Hongyu He

Faculty Publications

Let G be a real semisimple group. Two important invariants are associated with the equivalence class of an irreducible unitary representation of G, namely, the associated variety of the annihilator in the universal enveloping algebra and Howe's N-spectrum, where N is a nilpotent subgroup of G. The associated variety is defined in a purely algebraic way. The N-spectrum is defined analytically. In this paper, we prove some results about the relation between associated variety and N-associated variety, where N is a subgroup of G. We then relate N-associated variety with Howe's N-spectrum when N is abelian. This enables us to …


Further Results On Input-To-State Stability For Nonlinear Systems With Delayed Feedbacks, Frédéric Mazenc, Michael Malisoff, Zongli Lin Sep 2008

Further Results On Input-To-State Stability For Nonlinear Systems With Delayed Feedbacks, Frédéric Mazenc, Michael Malisoff, Zongli Lin

Faculty Publications

We consider a class of nonlinear control systems for which stabilizing feedbacks and corresponding Lyapunov functions for the closed-loop systems are available. In the presence of feedback delays and actuator errors, we explicitly construct input-to-state stability (ISS) Lyapunov-Krasovskii functionals for the resulting feedback delayed dynamics, in terms of the available Lyapunov functions for the original undelayed dynamics, which establishes that the closed-loop systems are input-to-state stable (ISS) with respect to actuator errors. We illustrate our results using a generalized system from identification theory and other examples. © 2008 Elsevier Ltd. All rights reserved.


Measuring The Deposited Energy By The Scintillation Calorimeter In The Atic Experiment, A. D. Panov, V. I. Zatsepin, N. V. Sokolskaya, J. H. Adams, H. S. Ahn, G. L. Bashindzhagyan, J. W. Watts, J. P. Wefel, J. Wu, O. Ganel, T. G. Guzik, R. M. Gunashingha, J. Isbert, K. C. Kim, M. Christl, E. N. Kouznetsov, M. I. Panasyuk, E. S. Seo, J. Chang, W. K.H. Schmidt, A. R. Fazely Sep 2008

Measuring The Deposited Energy By The Scintillation Calorimeter In The Atic Experiment, A. D. Panov, V. I. Zatsepin, N. V. Sokolskaya, J. H. Adams, H. S. Ahn, G. L. Bashindzhagyan, J. W. Watts, J. P. Wefel, J. Wu, O. Ganel, T. G. Guzik, R. M. Gunashingha, J. Isbert, K. C. Kim, M. Christl, E. N. Kouznetsov, M. I. Panasyuk, E. S. Seo, J. Chang, W. K.H. Schmidt, A. R. Fazely

Faculty Publications

The purpose of the ATIC balloon experiment is to measure the energy spectra of primary cosmic rays with individual charge resolution from protons to iron over the energy range from ∼ 50 GeV to 200 TeV. The particle energy is measured by a bismuth germanate (BGO) scintillation calorimeter. The procedure of calorimeter calibration is described, in particular, calibration of the temperature dependence of the calorimeter sensitivity using the data of in-flight measurements. A technique for determining the energy deposited in the calorimeter in view of the temperature dependence of its sensitivity is presented. The maximum systematic error in determining the …


Furman Magazine. Volume 51, Issue 2 - Full Issue, Furman University Sep 2008

Furman Magazine. Volume 51, Issue 2 - Full Issue, Furman University

Furman Magazine

No abstract provided.


Scientific Evolution, Jim Stewart, Brian Goess, David Moffett, Weston Dripps, Victoria Turgeon Sep 2008

Scientific Evolution, Jim Stewart, Brian Goess, David Moffett, Weston Dripps, Victoria Turgeon

Furman Magazine

Designed to foster interdisciplinary research and collaboration, the Townes Center is set to transform the teaching of science at Furman.


Change In Course, Jim Stewart Sep 2008

Change In Course, Jim Stewart

Furman Magazine

Furman introduces a revamped academic calendar and curriculum designed to invigorate intellectual activity on campus.


Furman Alumni News, Furman University Sep 2008

Furman Alumni News, Furman University

Furman Magazine

No abstract provided.


Take A Trip To Beaufort, Furman University Sep 2008

Take A Trip To Beaufort, Furman University

Furman Magazine

No abstract provided.