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2006

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Articles 3451 - 3480 of 5872

Full-Text Articles in Physical Sciences and Mathematics

The Pseudosquares Prime Sieve, Jonathan P. Sorenson Jan 2006

The Pseudosquares Prime Sieve, Jonathan P. Sorenson

Scholarship and Professional Work - LAS

We present the pseudosquares prime sieve, which finds all primes up to n.

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Pumping-Induced Drawdown And Stream Depletion In A Leaky Aquifer System, James J. Butler Jr., Xiaoyong Zhan, Vitaly A. Zlotnik Jan 2006

Pumping-Induced Drawdown And Stream Depletion In A Leaky Aquifer System, James J. Butler Jr., Xiaoyong Zhan, Vitaly A. Zlotnik

Department of Earth and Atmospheric Sciences: Faculty Publications

The impact of ground water pumping on nearby streams is often estimated using analytic models of the interconnected stream-aquifer system. A common assumption of these models is that the pumped aquifer is underlain by an impermeable formation. A new semianalytic solution for drawdown and stream depletion has been developed that does not require this assumption. This solution shows that pumping-induced flow (leakage) through an underlying aquitard can be an important recharge mechanism in many stream-aquifer systems. The relative importance of this source of recharge increases with the distance between the pumping well and the stream. The distance at which leakage …

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Understanding Farmers’ Forecast Use From Their Beliefs, Values, Social Norms, And Perceived Obstacles*, Q. Steven Hu, Lisa M. Pytlikzillig, Gary D. Lynne, Alan Tomkins, William J. Waltman, Michael J. Hayes, Kenneth Hubbard, Ikrom Artikov, Stacey Hoffman, Donald A. Wilhite Jan 2006

Understanding Farmers’ Forecast Use From Their Beliefs, Values, Social Norms, And Perceived Obstacles*, Q. Steven Hu, Lisa M. Pytlikzillig, Gary D. Lynne, Alan Tomkins, William J. Waltman, Michael J. Hayes, Kenneth Hubbard, Ikrom Artikov, Stacey Hoffman, Donald A. Wilhite

Department of Earth and Atmospheric Sciences: Faculty Publications

Although the accuracy of weather and climate forecasts is continuously improving and new information retrieved from climate data is adding to the understanding of climate variation, use of the forecasts and climate information by farmers in farming decisions has changed little. This lack of change may result from knowledge barriers and psychological, social, and economic factors that undermine farmer motivation to use forecasts and climate information. According to the theory of planned behavior (TPB), the motivation to use forecasts may arise from personal attitudes, social norms, and perceived control or ability to use forecasts in specific decisions. These attributes are …

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Coupling Between Primary Terrestrial Succession And The Trophic Development Of Lakes At Glacier Bay, Alaska, D. R. Engstrom, Sherilyn C. Fritz Jan 2006

Coupling Between Primary Terrestrial Succession And The Trophic Development Of Lakes At Glacier Bay, Alaska, D. R. Engstrom, Sherilyn C. Fritz

Department of Earth and Atmospheric Sciences: Faculty Publications

The natural eutrophication of lakes is still an accepted concept in limnology, arising as it does from the earliest efforts to classify lakes and place them in an evolutionary sequence. Recent studies of newly formed lakes at Glacier Bay, Alaska, only partially support this idea, and suggest more variable trends in lake trophic development which are under local (catchment-level) control. Here we use sediment cores from several lakes in Glacier Bay National Park to examine the relationship between successional changes in catchment vegetation and trends in water-column nitrogen (a limiting nutrient) and lake primary production. Terrestrial succession at Glacier Bay …

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Diatom Paleolimnological Record Of Holocene Climatic And Environmental Change In The Altai Mountains, Siberia, Karlyn S. Westover, Sherilyn C. Fritz, Tatyana A. Blyakharchuk, Herbert E. Wright Jan 2006

Diatom Paleolimnological Record Of Holocene Climatic And Environmental Change In The Altai Mountains, Siberia, Karlyn S. Westover, Sherilyn C. Fritz, Tatyana A. Blyakharchuk, Herbert E. Wright

Department of Earth and Atmospheric Sciences: Faculty Publications

The sedimentary diatom records of three shallow lakes in the Altai Mountains, southern Siberia, were examined to assess the nature and timing of Holocene environmental changes. Few paleoenvironmental records, especially reconstructions not based on pollen, have been reported from this region. The lakes differ in elevation, annual precipitation, and catchment vegetation. Diatom assemblages in all lakes were dominated for the entire period of record by small benthic species of Pseudostaurosira Williams & Round, Staurosira Ehrenberg, and Staurosirella Williams & Round. Planktonic taxa only occur in very low abundances (<5%). The most diverse diatom flora was found in Dzhangyskol, which is situated at the lowest elevation within a forested catchment. A lack of detailed information on the ecological preferences of the dominant taxa and the complexity of environmental drivers make direct interpretation of the diatom record difficult. However, other proxies suggest that dramatic shifts in dominance between Staurosira elliptica and Staurosirella pinnata in Grusha Ozero reflect millennial-scale variability …

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Information Hiding And Retrieval In Rydberg Wave Packets Using Half-Cycle Pulses, J.M. Murray, S.N. Pisharody, H. Wen, Chitra Rangan Jan 2006

Information Hiding And Retrieval In Rydberg Wave Packets Using Half-Cycle Pulses, J.M. Murray, S.N. Pisharody, H. Wen, Chitra Rangan

Physics Publications

We demonstrate an information hiding and retrieval scheme with the relative phases between states in a Rydberg wave packet acting as the bits of a data register. We use a terahertz half-cycle pulse (HCP) to transfer phase-encoded information from an optically accessible angular momentum manifold to another manifold which is not directly accessed by our laser pulses, effectively hiding the information from our optical interferometric measurement techniques. A subsequent HCP acting on these wave packets reintroduces the information back into the optically accessible data register manifold which can then be read out.

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Nuclear Charge Radius For He3, D. C. Morton, Q. Wu, Gordon W. F. Drake Jan 2006

Nuclear Charge Radius For He3, D. C. Morton, Q. Wu, Gordon W. F. Drake

Physics Publications

An rms nuclear charge radius rc =1.9642 (11) fm for He3 is derived from measurements of the 2 S13 -2 P03 isotope shift combined with the best available data on the fine structure of He4, the hyperfine structure of He3, and an assumed rc =1.673 (1) fm for He4. The result removes a small discrepancy between some older spectroscopic determinations of rc for He3 from this transition and a more recent measurement. © 2006 The American Physical Society.

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Emergence And Migration Of A Nearshore Bar: Sediment Flux And Morphological Change On A Multi-Barred Beach In The Great Lakes, B. Greenwood, A. Permanand-Schwartz, Chris Houser Jan 2006

Emergence And Migration Of A Nearshore Bar: Sediment Flux And Morphological Change On A Multi-Barred Beach In The Great Lakes, B. Greenwood, A. Permanand-Schwartz, Chris Houser

Earth & Environmental Sciences Publications

Burley Beach (southeastern Lake Huron) exhibits a multi-barred shoreface, the long-term equilibrium morphology characteristic of many low angle, sandy beaches in the Canadian Great Lakes. During a single major storm, a new bar emerged 50-60 m offshore as an irregular trough-crest form, through differential erosion of an existing shore terrace. Emergence, bar growth and offshore migration were associated with. (a) an overall negative sediment balance in the inner surf zone initially (-2.30 m3/m beach width), but with a large positive sediment balance (+5.10 m3/m) subsequent to the storm peak and during the storm decay; (b) progradation of the beach step …

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Service-Learning In Watershed-Based Initiatives: Keys To Education For Sustainability In Geography?, James Eflin, Amy L. Sheaffer Jan 2006

Service-Learning In Watershed-Based Initiatives: Keys To Education For Sustainability In Geography?, James Eflin, Amy L. Sheaffer

Service Learning, General

A call for combining the strengths of geographic education with environmental education to produce an 'education for sustainability' addresses local problems for sustainable development. A place-based approach encourages civic responsibility among students. Using service-learning to extend education beyond the classroom in this case study connected students with local clients in a watershed-based initiative. Theoretical underpinnings of service-learning for geographic education are discussed, and the case study is viewed from instructor, student, and client perspectives to identify successful outcomes and provide suggestions for those who might adopt service-learning for the first time.

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Lewis And Protic Acid Mediated Nicholas Reactions Of 3-Acetoxycyclohept-1-En-4-Ynedicobalt Hexacarbonyl: Site Selectivity Of Nucleophile Incorporation, Joseph Dimartino, James R. Green Jan 2006

Lewis And Protic Acid Mediated Nicholas Reactions Of 3-Acetoxycyclohept-1-En-4-Ynedicobalt Hexacarbonyl: Site Selectivity Of Nucleophile Incorporation, Joseph Dimartino, James R. Green

Chemistry and Biochemistry Publications

Nicholas reactions on the cation derived from the cyclic allylic acetate alkynedicobalt complex 1 favour the gamma-site kinetically for most nucleophiles, with increasing amounts of of-products in cases with greater nucleophilicity. Some regiocontrol in introduction of a specific nucleophilic fragment is possible by using different nucleophiles. Under conditions where reversibility is possible, the thermodynamically favoured site is exclusively gamma-. (c) 2005 Elsevier Ltd. All rights reserved.

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Organizational Transformation Through Business Models: A Framework For Business Model Design, Peter Keen, Sajda Qureshi Jan 2006

Organizational Transformation Through Business Models: A Framework For Business Model Design, Peter Keen, Sajda Qureshi

Information Systems and Quantitative Analysis Faculty Proceedings & Presentations

Organizations are increasingly inter-connected as they source talent, goods and services from other organizations located in disparate parts of the world. They seek new ways of creating value for themselves, customers and partners. They operate outside and across traditional industry boundaries and definitions. These innovations have lead to a focus on business models as a fundamental statement of direction and identity. This paper highlights what is known about the business model concept and where and why it differs from more established concepts of business strategy. It illustrates how the application of business models has transformed organizations. The contribution of this …

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Lithofacies, Architecture And Sequence Stratigraphic Interpretation Of The Upper Pennsylvanian Indian Cave Sandstone, Northern Midcontinent Shelf, U.S.A. (Southeastern Nebraska)., Steven A. Fischbein Ph.D. Jan 2006

Lithofacies, Architecture And Sequence Stratigraphic Interpretation Of The Upper Pennsylvanian Indian Cave Sandstone, Northern Midcontinent Shelf, U.S.A. (Southeastern Nebraska)., Steven A. Fischbein Ph.D.

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

The Virgilian “Indian Cave Sandstone” (ICS) is herein redefined as at least four incised valley fills (IVFs) of at least two different ages. These IVFs are composed of irregularly bounded, tabular-lenticular units of trough cross-bedded sandstone, grading vertically into tabular-lenticular units of mudstone-and-sandstone-dominated heterolith. Three IVFs, wider (< 2 km) than they are deep (> 30 m), are composed of multiple storeys grading upward from fluvial-to-estuarine facies to upper-estuarine facies. Storey boundaries are delineated by bounding surfaces underlying conglomerates with heterolithic clasts. One IVF (Honey Creek, NE) is smaller than the others, (> 0.5 km wide and > 25 m deep) and appears to be composed of a …

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Temperature Dependence Of The Electron Diffusion Coefficient In Electrolyte-Filled Tio2 Nanoparticle Films: Evidence Against Multiple Trapping In Exponential Conduction-Band Tails, Nikos Kopidakis, Kurt D. Benkstein, Jao Van De Lagemaat, Quan Yuan, Eric A. Schiff Jan 2006

Temperature Dependence Of The Electron Diffusion Coefficient In Electrolyte-Filled Tio2 Nanoparticle Films: Evidence Against Multiple Trapping In Exponential Conduction-Band Tails, Nikos Kopidakis, Kurt D. Benkstein, Jao Van De Lagemaat, Quan Yuan, Eric A. Schiff

Physics - All Scholarship

The temperature and photoexcitation density dependences of the electron transport dynamics in electrolytefilled mesoporous TiO2 nanoparticle films were investigated by transient photocurrent measurements. The thermal activation energy of the diffusion coefficient of photogenerated electrons ranged from 0.19–0.27 eV, depending on the specific sample studied. The diffusion coefficient also depends strongly on the photoexcitation density; however, the activation energy has little, if any, dependence on the photoexcitation density. The light intensity dependence can be used to infer temperature-independent dispersion parameters in the range 0.3–0.5. These results are inconsistent with the widely used transport model that assumes multiple trapping of electrons in …

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Hole Mobilities And The Physics Of Amorphous Silicon Solar Cells, Eric A. Schiff Jan 2006

Hole Mobilities And The Physics Of Amorphous Silicon Solar Cells, Eric A. Schiff

Physics - All Scholarship

The effects of low hole mobilities in the intrinsic layer of pin solar cells are illustrated using general computer modeling; in these models electron mobilities are assumed to be much larger than hole values. The models reveal that a low hole mobility can be the most important photocarrier transport parameter in determining the output power of the cell, and that the effects of recombination parameters are much weaker. Recent hole drift-mobility measurements in a-Si:H are compared. While hole drift mobilities in intrinsic a-Si:H are now up to tenfold larger than two decades ago, even with recent materials a-Si:H cells are …

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Temperature Dependence Of The Electron Diffusion Coefficient In Electrolyte-Filled Tio2, Nikos Kopidakis, Kurt D. Benkstein, Arthur J. Frank, Quan Yuan, Eric A. Schiff Jan 2006

Temperature Dependence Of The Electron Diffusion Coefficient In Electrolyte-Filled Tio2, Nikos Kopidakis, Kurt D. Benkstein, Arthur J. Frank, Quan Yuan, Eric A. Schiff

Physics - All Scholarship

The temperature and photoexcitation density dependences of the electron transport dynamics in electrolytefilled mesoporous TiO2 nanoparticle films were investigated by transient photocurrent measurements. The thermal activation energy of the diffusion coefficient of photogenerated electrons ranged from 0.19–0.27 eV, depending on the specific sample studied. The diffusion coefficient also depends strongly on the photoexcitation density; however, the activation energy has little, if any, dependence on the photoexcitation density. The light intensity dependence can be used to infer temperature-independent dispersion parameters in the range 0.3–0.5. These results are inconsistent with the widely used transport model that assumes multiple trapping of electrons in …

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Hole Mobility Limit Of Amorphous Silicon Solar Cells, Jiang Liang, Eric A. Schiff, S. Guha, Baojie Yan, Jeff Yang Jan 2006

Hole Mobility Limit Of Amorphous Silicon Solar Cells, Jiang Liang, Eric A. Schiff, S. Guha, Baojie Yan, Jeff Yang

Physics - All Scholarship

We present temperature-dependent measurements and modeling for a thickness series of hydrogenated amorphous silicon nip solar cells. The comparison indicates that the maximum power density (PMAX) from the as-deposited cells has achieved the hole-mobility limit established by valence bandtail trapping, and PMAX is thus not significantly limited by intrinsic-layer dangling bonds or by the doped layers and interfaces. Measurements of the temperature-dependent properties of light-soaked cells show that the properties of as-deposited and light-soaked cells converge below 250 K; a model perturbing the valence band tail traps with a density of dangling bonds accounts adequately for the convergence effect.

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Effect Of Electric Field Doping On The Anisotropic Magnetoresistance In Doped Manganites, X. Hong, J. -B. Yau, J. D. Hoffman, C. H. Ahn Jan 2006

Effect Of Electric Field Doping On The Anisotropic Magnetoresistance In Doped Manganites, X. Hong, J. -B. Yau, J. D. Hoffman, C. H. Ahn

Xia Hong Publications

We have modulated the anisotropic magnetoresistance (AMR) in 3–4 nm manganite films using the ferroelectric field effect—a method that electrostatically varies the carrier density without affecting the lattice distortion. While significant changes have been induced in TC and p, the AMR ratio remains the same when the magnetic state is not changed. This scaling behavior is in striking contrast to chemical doping results, where similar modulation of the carrier concentration (~0.1/Mn) changes the AMR ratio by ≥30%. The results reveal unambiguously the dominant role of chemical distortion in determining the AMR in manganites.

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Existence Of Optimal Controls For Singular Control Problems With State Constraints, Amarjit Budhiraja, Kevin Ross Jan 2006

Existence Of Optimal Controls For Singular Control Problems With State Constraints, Amarjit Budhiraja, Kevin Ross

Statistics

We establish the existence of an optimal control for a general class of singular control problems with state constraints. The proof uses weak convergence arguments and a time rescaling technique. The existence of optimal controls for Brownian control problems, associated with a broad family of stochastic networks, follows as a consequence.

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Management Strategies In The Wildland-Urban Interface Of Southern California And Their Effect On Fire Behavior And Environmental Impacts, Christopher Dicus Jan 2006

Management Strategies In The Wildland-Urban Interface Of Southern California And Their Effect On Fire Behavior And Environmental Impacts, Christopher Dicus

Natural Resources Management and Environmental Sciences

This paper discusses varying management strategies in wildland-urban interface communities of southern California in terms of their effects on potential fire behavior and residual environmental impacts. A century of fire exclusion policies there and throughout the United States has led to immense fuel loading and declining ecosystem health, which coupled with a burgeoning population relocating to wildland areas, has annually heightened the threat of devastating wildfires. Successful management strategies must consider elements of suppression needs, community education, construction and development standards, and vegetation manipulation, each of which will vary dependant on the ecosystem and socioeconomic conditions of the area considered. …

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Effects Of Lop And Scatter Slash Treatment On Potential Fire Behavior And Soil Erosion Following A Selection Harvest In A Coast Redwood Forest, Kyle W. Jacobson, Christopher Dicus Jan 2006

Effects Of Lop And Scatter Slash Treatment On Potential Fire Behavior And Soil Erosion Following A Selection Harvest In A Coast Redwood Forest, Kyle W. Jacobson, Christopher Dicus

Natural Resources Management and Environmental Sciences

Even though harvesting timber is one method of reducing fuel continuity and subsequent potential fire behavior, the residual slash can greatly increase the surface fuel loading and subsequent risk of wildfire on harvested sites. Fire behavior following silvicultural treatments to a stand can vary greatly, with both depth and loading playing a significant role (Nives 1989). Surface fuels and subsequent potential fire behavior has been shown to increase in the first year after harvest in coast redwood forests (Sequoia sempervirens (D. Don) Endl.) (Dicus 2003), which threatens not only natural resources but also structures in an ever-increasing wildland-urban interface. Alternatively, …

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Effects Of Fuel Loading On Potential Fire Behavior And Soil Erosion In Coast Redwood Stands, Eric Just, Christopher Dicus Jan 2006

Effects Of Fuel Loading On Potential Fire Behavior And Soil Erosion In Coast Redwood Stands, Eric Just, Christopher Dicus

Natural Resources Management and Environmental Sciences

Commercial timber harvesting typically reduces aerial fuel loading and continuity, but can actually heighten fire activity through increased surface fuel loading (Agee 1997). Fuel depth and loading, which typically increase after harvest, play a significant role in fire intensity and rate of spread in redwood forests (Sequoia sempervirens) (D. Don.) Endl.) (Nives 1989), which are significant predictors of redwood mortality (Finney and Martin 1993). However, residual slash fuels may simultaneously reduce erosion, which may be of greater importance in some areas because they intercept rainfall and soil particles dispersed by overland flow (Fernandez et al. 2004). The relationship of surface …

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Solute Transport In A Medium With Spatially Variable Porosity, B Malama, W Barrash, D W Hyndman, G Nelson Jan 2006

Solute Transport In A Medium With Spatially Variable Porosity, B Malama, W Barrash, D W Hyndman, G Nelson

Natural Resources Management and Environmental Sciences

No abstract provided.

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On The Reliability Of An N-Component System, Don Rawlings, Lawrence Sze Jan 2006

On The Reliability Of An N-Component System, Don Rawlings, Lawrence Sze

Mathematics

Under assumptions compatible with the theory of Markov chains, we use a property of Vandermonde matrices to examine the reliability of an n-component system of production or service.

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On The Existence Of Infinitely Many Closed Geodesics On Orbifolds Of Revolution, Joseph Borzellino, Christopher R. Jordan-Squire, Gregory C. Petrics, D. Mark Sullivan Jan 2006

On The Existence Of Infinitely Many Closed Geodesics On Orbifolds Of Revolution, Joseph Borzellino, Christopher R. Jordan-Squire, Gregory C. Petrics, D. Mark Sullivan

Mathematics

Using the theory of geodesics on surfaces of revolution, we introduce the period function. We use this as our main tool in showing that any two-dimensional orbifold of revolution homeomorphic to S2 must contain an infinite number of geometrically distinct closed geodesics. Since any such orbifold of revolution can be regarded as a topological two-sphere with metric singularities, we will have extended Bangert’s theorem on the existence of infinitely many closed geodesics on any smooth Riemannian two-sphere. In addition, we give an example of a two-sphere cone-manifold of revolution which possesses a single closed geodesic, thus showing that Bangert’s result …

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An Empirical Evaluation Of The Impact Of Test-Driven Development On Software Quality, David S. Janzen Jan 2006

An Empirical Evaluation Of The Impact Of Test-Driven Development On Software Quality, David S. Janzen

Computer Science and Software Engineering

Test-driven development (TDD) has gained recent attention with the popularity of the Extreme Programming agile software development methodology. Advocates of TDD rely primarily on anecdotal evidence with relatively little empirical evidence of the benefits of the practice. This research is the first comprehensive evaluation of how TDD affects software architecture and internal design quality. Formal controlled experiments were conducted in undergraduate and graduate academic courses, in a professional training course, and with in-house professional development projects in a Fortune 500 company. The experiments involved over 230 student and professional programmers working on almost five hundred software projects ranging in size …

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Advancing Candidate Link Generation For Requirements Tracing: The Study Of Methods, Jane Huffman Hayes, Alex Dekhtyar, Senthil Karthikeyan Sundaram Jan 2006

Advancing Candidate Link Generation For Requirements Tracing: The Study Of Methods, Jane Huffman Hayes, Alex Dekhtyar, Senthil Karthikeyan Sundaram

Computer Science and Software Engineering

This paper addresses the issues related to improving the overall quality of the dynamic candidate link generation for the requirements tracing process for verification and validation and independent verification and validation analysts. The contribution of the paper is four-fold: we define goals for a tracing tool based on analyst responsibilities in the tracing process, we introduce several new measures for validating that the goals have been satisfied, we implement analyst feedback in the tracing process, and we present a prototype tool that we built, RETRO (REquirements TRacing On-target), to address these goals. We also present the results of a study …

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The Caster Black Hole Finder Probe, Mark L. Mcconnell, Peter F. Bloser, G L. Case, M L. Cherry, J Cravens, T G. Guzik, K Hurley, R M. Kippen, John R. Macri, R S. Miller, W Paciesas, James M. Ryan, B Schaefer, J G. Stacy, W T. Vestrand, J P. Wefel Jan 2006

The Caster Black Hole Finder Probe, Mark L. Mcconnell, Peter F. Bloser, G L. Case, M L. Cherry, J Cravens, T G. Guzik, K Hurley, R M. Kippen, John R. Macri, R S. Miller, W Paciesas, James M. Ryan, B Schaefer, J G. Stacy, W T. Vestrand, J P. Wefel

Space Science Center

The primary scientific mission of the Black Hole Finder Probe (BHFP), part of the NASA Beyond Einstein program, is to survey the local Universe for black holes over a wide range of mass and accretion rate. One approach to such a survey is a hard X‐ray coded‐aperture imaging mission operating in the 10–600 keV energy band. The development of new inorganic scintillator materials provides improved performance that is well suited to the BHFP science requirements. Detection planes formed with these materials coupled with a new generation of readout devices represent a major advancement in the performance capabilities of scintillator‐based gamma …

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Simulated Performance Of 3-Dti Gamma-Ray Telescope Concepts, Peter F. Bloser, Mark L. Mcconnell, James M. Ryan, Louis M. Barbier, Alan Centa, Stanley D. Hunter, John F. Krizmanic, Jason T. Link, Geoergia A. De Nolfo, Seunghee Son Jan 2006

Simulated Performance Of 3-Dti Gamma-Ray Telescope Concepts, Peter F. Bloser, Mark L. Mcconnell, James M. Ryan, Louis M. Barbier, Alan Centa, Stanley D. Hunter, John F. Krizmanic, Jason T. Link, Geoergia A. De Nolfo, Seunghee Son

Space Science Center

We present Monte Carlo simulations of two astronomical gamma-ray telescope concepts based on the ThreeDimensional Track Imager (3- DTI) detector. The 3-DTI consists of a time projection chamber with two-dimensional, crossedstrip micro-well detector readout. The full three- dimensional reconstruction of charged-particle tracks in the gas volume is obtained from transient digitizers, which record the time signature of the charge collected in the wells of each strip. Such detectors hold great promise for advanced Compton telescope (ACT) and advanced pair telescope (APT) concepts due to the very precise measurement of charged particle momenta that is possible (Compton recoil electrons and electron-positron …

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Two Way Diffusion Model For The Recording Mechanism In A Self-Developing Dry Acrylamide Photopolymer, Suzanne Martin, Izabela Naydenova, Raghavendra Jallapuram, Robert Howard, Vincent Toal Jan 2006

Two Way Diffusion Model For The Recording Mechanism In A Self-Developing Dry Acrylamide Photopolymer, Suzanne Martin, Izabela Naydenova, Raghavendra Jallapuram, Robert Howard, Vincent Toal

Conference Papers

In our most recent study [1] diffusion constants were measured in the simplified monoacrylamide version of a dry acrylamide based photopolymer holographic recording material developed in the Centre for Industrial and Engineering Optics. In this paper we report diffusion constants for the commonly used photopolymer formulation, which also contains the crosslinker bisacrylamide. A physical model for the recording mechanism is proposed which explains the two way diffusion observed in both systems, and is in agreement with much of the previously observed behaviour of the material, particularly in regard to dependence of diffraction efficiency growth on spatial frequency and persistence of …

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Optimal Image Blending For Underwater Mosaics, Fan Gu, Yuri Rzhanov Jan 2006

Optimal Image Blending For Underwater Mosaics, Fan Gu, Yuri Rzhanov

Center for Coastal and Ocean Mapping

No abstract provided.

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