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2007

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Full-Text Articles in Physical Sciences and Mathematics

Afci Quarterly Input – Unlv April 1 Through June 30, 2007, Harry Reid Center For Environmental Studies. Nuclear Science And Technology Division Jun 2007

Afci Quarterly Input – Unlv April 1 Through June 30, 2007, Harry Reid Center For Environmental Studies. Nuclear Science And Technology Division

Transmutation Research Program Reports (TRP)

Quarterly report highlighting research projects, activities and objectives of the Transmutation Research Program at the Nuclear Science & Technology Division, Harry Reid Research Center.

The University of Nevada, Las Vegas supports the AFCI through research and development of technologies for economic and environmentally sound refinement of spent nuclear fuel. The UNLV program has four components: infrastructure, international collaboration, student-based research, and management and program support.


Front Matter Jun 2007

Front Matter

Journal of Digital Forensics, Security and Law

No abstract provided.


Back Matter Jun 2007

Back Matter

Journal of Digital Forensics, Security and Law

No abstract provided.


The Introduction And Emergence Of Wildlife Diseases In North America, Robert G. Mclean Jun 2007

The Introduction And Emergence Of Wildlife Diseases In North America, Robert G. Mclean

United States Department of Agriculture Wildlife Services: Staff Publications

Contents:

Specific Invasive and Emerging Wildlife Diseases: West Nile Virus, Hantavirus, Lyme Disease, Monkeypox, Raccoon Rabies
Foreign Wildlife Diseases That Could Invade the United States: Highly Pathogenic Avian Influenza, Rift Valley Fever, Nipah Virus, Japanese Encephalitis
Prevention, Detection, and Control of Invading and Emerging Diseases
References


Masthead Jun 2007

Masthead

Journal of Digital Forensics, Security and Law

No abstract provided.


Two Modes Of Accelerated Glacier Sliding Related To Water, Joel T. Harper, Neil Humphrey, W. T. Pfeffer, Brian Lazar Jun 2007

Two Modes Of Accelerated Glacier Sliding Related To Water, Joel T. Harper, Neil Humphrey, W. T. Pfeffer, Brian Lazar

Geosciences Faculty Publications

We present the first glacier-wide detailed measurement of basal effective pressure and related observations including bed separation to elucidate the role of water in sliding. The hard bedded glacier instrumented in our study exhibited two phases of accelerated sliding motion apparently driven by separate mechanisms. The first acceleration phase (up to 5 fold increase in speed) was closely tied to an increase in bed separation. The faster second phase (up to 9 fold increase in speed) was related to an unusually high level of connectivity of subglacial waters. We infer the first mode was related to cavity opening and the …


Discrete Algorithms For Analysis Of Genotype Data, Dumitru Brinza Jun 2007

Discrete Algorithms For Analysis Of Genotype Data, Dumitru Brinza

Computer Science Dissertations

Accessibility of high-throughput genotyping technology makes possible genome-wide association studies for common complex diseases. When dealing with common diseases, it is necessary to search and analyze multiple independent causes resulted from interactions of multiple genes scattered over the entire genome. The optimization formulations for searching disease-associated risk/resistant factors and predicting disease susceptibility for given case-control study have been introduced. Several discrete methods for disease association search exploiting greedy strategy and topological properties of case-control studies have been developed. New disease susceptibility prediction methods based on the developed search methods have been validated on datasets from case-control studies for several common …


A Global Mhd Simulation Of An Event With A Quasi-Steady Northward Imf Component, V G. Merkin, J G. Lyon, B J. Anderson, H Korth, C C. Goodrich, K Papadopoulos Jun 2007

A Global Mhd Simulation Of An Event With A Quasi-Steady Northward Imf Component, V G. Merkin, J G. Lyon, B J. Anderson, H Korth, C C. Goodrich, K Papadopoulos

Dartmouth Scholarship

We show results of the Lyon-Fedder-Mobarry (LFM) global MHD simulations of an event previously ex- amined using Iridium spacecraft observations as well as DMSP and IMAGE FUV data. The event is chosen for the steady northward IMF sustained over a three-hour pe- riod during 16 July 2000. The Iridium observations showed very weak or absent Region 2 currents in the ionosphere, which makes the event favorable for global MHD model- ing. Here we are interested in examining the model’s per- formace during weak magnetospheric forcing, in particular, its ability to reproduce gross signatures of the ionospheric currents and convection pattern …


Estimating Time-To-Event From Longitudinal Categorical Data Using Random Effects Markov Models: Application To Multiple Sclerosis Progression, Micha Mandel, Rebecca A. Betensky Jun 2007

Estimating Time-To-Event From Longitudinal Categorical Data Using Random Effects Markov Models: Application To Multiple Sclerosis Progression, Micha Mandel, Rebecca A. Betensky

Harvard University Biostatistics Working Paper Series

No abstract provided.


Simultaneous Confidence Intervals Based On The Percentile Bootstrap Approach, Micha Mandel, Rebecca A. Betensky Jun 2007

Simultaneous Confidence Intervals Based On The Percentile Bootstrap Approach, Micha Mandel, Rebecca A. Betensky

Harvard University Biostatistics Working Paper Series

No abstract provided.


Calculations On The End-Group Conformational Barrier In Carotenoids And A Study Of The Bioavailability Of Xanthophyll Esters In Humans, Francesca Alvarez-Calderon Jun 2007

Calculations On The End-Group Conformational Barrier In Carotenoids And A Study Of The Bioavailability Of Xanthophyll Esters In Humans, Francesca Alvarez-Calderon

FIU Electronic Theses and Dissertations

The present study measures the increase in serum carotenoid concentration in 30 healthy individuals after supplementation with a low dose xanthophyll ester (3 and 6 mg of lutein equivalent/per day) when compared to a placebo. Serum levels of carotenoids were measured using HPLC and showed an increase in the concentration of lutein, zeaxanthin and four lutein metabolites proportional to dose.

In order to further assess the importance of the end-group structure in carotenoids we have investigated the influence of the end-group type and functionality on the conformational energy barrier. We used the density functional method implemented on GAUSSIAN 98 to …


A Security Assessment Of Trusted Platform Modules, Evan R. Sparks Jun 2007

A Security Assessment Of Trusted Platform Modules, Evan R. Sparks

Dartmouth College Undergraduate Theses

Trusted Platform Modules (TPMs) are becoming ubiquitous devices included in newly released personal computers. Broadly speaking, the aim of this technology is to provide a facility for authenticating the platform on which they are running: they are able to measure attest to the authenticity of a hardware and software configuration. Designed to be cheap, commodity devices which motherboard and processor vendors can include in their products with minimal marginal cost, these devices have a good theoretical design. Unfortunately, there exist several practical constraints on the effectiveness of TPMs and the architectures which employ them which leave them open to attack. …


Rethinking Consistency Management In Real-Time Collaborative Editing Systems, Jon Anderson Preston Jun 2007

Rethinking Consistency Management In Real-Time Collaborative Editing Systems, Jon Anderson Preston

Computer Science Dissertations

Networked computer systems offer much to support collaborative editing of shared documents among users. Increasing concurrent access to shared documents by allowing multiple users to contribute to and/or track changes to these shared documents is the goal of real-time collaborative editing systems (RTCES); yet concurrent access is either limited in existing systems that employ exclusive locking or concurrency control algorithms such as operational transformation (OT) may be employed to enable concurrent access. Unfortunately, such OT based schemes are costly with respect to communication and computation. Further, existing systems are often specialized in their functionality and require users to adopt new, …


Summertime Influence Of Asian Pollution In The Free Troposphere Over North America, Q Liang, L Jaegle, R C. Hudman, S Turquety, D J. Jacob, Melody A. Avery, E V. Browell, G W. Sachse, D R. Blake, William H. Brune, Xinrong Ren, Ronald C. Cohen, Jack E. Dibb, A Fried, H Fuelberg, M Porter, B J. Heikes, Greg Huey, H B. Singh, Paul Wennberg Jun 2007

Summertime Influence Of Asian Pollution In The Free Troposphere Over North America, Q Liang, L Jaegle, R C. Hudman, S Turquety, D J. Jacob, Melody A. Avery, E V. Browell, G W. Sachse, D R. Blake, William H. Brune, Xinrong Ren, Ronald C. Cohen, Jack E. Dibb, A Fried, H Fuelberg, M Porter, B J. Heikes, Greg Huey, H B. Singh, Paul Wennberg

Earth Sciences

We analyze aircraft observations obtained during INTEX-A (1 July to 14 August 2004) to examine the summertime influence of Asian pollution in the free troposphere over North America. By applying correlation analysis and principal component analysis (PCA) to the observations between 6 and 12 km, we find dominant influences from recent convection and lightning (13% of observations), Asia (7%), the lower stratosphere (7%), and boreal forest fires (2%), with the remaining 71% assigned to background. Asian air masses are marked by high levels of CO, O3, HCN, PAN, C2H2, C6H6, methanol, and SO4 2 –. The partitioning of NOy species …


Collaborative Proposal: Form And Function Of Phytoplankton In Unsteady, Low Reynolds-Number Flows, Peter Jumars, Lee Karp-Boss Jun 2007

Collaborative Proposal: Form And Function Of Phytoplankton In Unsteady, Low Reynolds-Number Flows, Peter Jumars, Lee Karp-Boss

University of Maine Office of Research Administration: Grant Reports

Small-scale flow dynamics at low Reynolds numbers (Re) are important to phytoplankton cells in delivery of nutrients, sensory detection by and physical encounter with herbivores, accumulation of bacterial populations in the "phycosphere" or region immediately surrounding phytoplankton cells and coagulation of cells themselves as a mechanism terminating blooms. In nature most phytoplankton experience unsteady flows, i.e., velocities near the cells that vary with time due to the intermittency of turbulence and to discontinuous, spatially distributed pumping by herbivores. This unsteadiness has not previously been taken into account in models or measurements with plankton. Moreover, there have been decade- and century- …


A 2650-Year-Long Record Of Environmental Change From Northern Yellowstone National Park Based On A Comparison Of Multiple Proxy Data, Cathy Whitlock, Walter Dean, Joseph Rosenbaum, Lora Stevens, Sherilyn C. Fritz, Brandi Bracht, Mitchell Power Jun 2007

A 2650-Year-Long Record Of Environmental Change From Northern Yellowstone National Park Based On A Comparison Of Multiple Proxy Data, Cathy Whitlock, Walter Dean, Joseph Rosenbaum, Lora Stevens, Sherilyn C. Fritz, Brandi Bracht, Mitchell Power

Department of Earth and Atmospheric Sciences: Faculty Publications

Geochemical, stable-isotope, pollen, charcoal, and diatom records were analyzed at high-resolution in cores obtained from Crevice Lake, a varved-sediment lake in northern Yellowstone National Park. The objective was to reconstruct the ecohydrologic, vegetation, and fire history of the watershed for the last 2650 years to better understand past climate variations at the forest-steppe transition. The data suggest a period of limited bottom-water anoxia, relatively wet winters, and cool springs and summers from 2650 to 2100 cal yrBP (700–150 BC). Dry warm conditions occurred between 2100 and 850–800 cal yrBP (150 BC and AD 1100–1150), when the lake was anoxic, winter …


Chemical Data Assimilation Estimates Of Continental U.S. Ozone And Nitrogen Budgets During The Intercontinental Chemical Transport Experiment-North America, R B. Pierce, T Schaack, J Al-Saadi, T D. Fairlie, Chieko Kittaka, Gretchen Lingenfelser, M Natarajan, J R. Olson, Amber Soja, Tom Zapotocny, A Lenzen, M A. Avery, James Stobie, Donald Johnson, Melody A. Avery, G W. Sachse, A M. Thompson, Ronald C. Cohen, Jack E. Dibb, J Crawford, Didier Rault, Randall Martin, Jim Szykman, Jack Fishman Jun 2007

Chemical Data Assimilation Estimates Of Continental U.S. Ozone And Nitrogen Budgets During The Intercontinental Chemical Transport Experiment-North America, R B. Pierce, T Schaack, J Al-Saadi, T D. Fairlie, Chieko Kittaka, Gretchen Lingenfelser, M Natarajan, J R. Olson, Amber Soja, Tom Zapotocny, A Lenzen, M A. Avery, James Stobie, Donald Johnson, Melody A. Avery, G W. Sachse, A M. Thompson, Ronald C. Cohen, Jack E. Dibb, J Crawford, Didier Rault, Randall Martin, Jim Szykman, Jack Fishman

Earth Sciences

Global ozone analyses, based on assimilation of stratospheric profile and ozone column measurements, and NOy predictions from the Real-time Air Quality Modeling System (RAQMS) are used to estimate the ozone and NOy budget over the continental United States during the July-August 2004 Intercontinental Chemical Transport Experiment-North America (INTEX-A). Comparison with aircraft, satellite, surface, and ozonesonde measurements collected during INTEX-A show that RAQMS captures the main features of the global and continental U.S. distribution of tropospheric ozone, carbon monoxide, and NOy with reasonable fidelity. Assimilation of stratospheric profile and column ozone measurements is shown to have a positive impact on the …


Improving Regional Ozone Modeling Through Systematic Evaluation Of Errors Using The Aircraft Observations During The International Consortium For Atmospheric Research On Transport And Transformation, M Mena-Carrasco, Youhua Tang, Gregory R. Carmichael, Tianfeng Chai, Narisara Thongbongchoo, J Elliott Campbell, S Kulkarni, Larry Horowitz, Jeffrey Vukovich, Melody A. Avery, William H. Brune, Jack E. Dibb, L K. Emmons, F Flocke, Glen Sachse, David Tan, R E. Shetter, R. Talbot, David G. Streets, D R. Blake Jun 2007

Improving Regional Ozone Modeling Through Systematic Evaluation Of Errors Using The Aircraft Observations During The International Consortium For Atmospheric Research On Transport And Transformation, M Mena-Carrasco, Youhua Tang, Gregory R. Carmichael, Tianfeng Chai, Narisara Thongbongchoo, J Elliott Campbell, S Kulkarni, Larry Horowitz, Jeffrey Vukovich, Melody A. Avery, William H. Brune, Jack E. Dibb, L K. Emmons, F Flocke, Glen Sachse, David Tan, R E. Shetter, R. Talbot, David G. Streets, D R. Blake

Earth Sciences

During the operational phase of the ICARTT field experiment in 2004, the regional air quality model STEM showed a strong positive surface bias and a negative upper troposphere bias (compared to observed DC-8 and WP-3 observations) with respect to ozone. After updating emissions from NEI 1999 to NEI 2001 (with a 2004 large point sources inventory update), and modifying boundary conditions, low-level model bias decreases from 11.21 to 1.45 ppbv for the NASA DC-8 observations and from 8.26 to −0.34 for the NOAA WP-3. Improvements in boundary conditions provided by global models decrease the upper troposphere negative ozone bias, while …


Reactive Nitrogen Distribution And Partitioning In The North American Troposphere And Lowermost Stratosphere, H B. Singh, L Salas, D Herlth, R Koyler, M A. Avery, J H. Crawford, R B. Pierce, Glen Sachse, D R. Blake, Ronald C. Cohen, T H. Bertram, A E. Perring, Paul J. Wooldridge, Jack E. Dibb, L Gregory Huey, R C. Hudman, S Turquety, L K. Emmons, F Flocke, Youhua Tang, Gregory R. Carmichael, Larry Horowitz Jun 2007

Reactive Nitrogen Distribution And Partitioning In The North American Troposphere And Lowermost Stratosphere, H B. Singh, L Salas, D Herlth, R Koyler, M A. Avery, J H. Crawford, R B. Pierce, Glen Sachse, D R. Blake, Ronald C. Cohen, T H. Bertram, A E. Perring, Paul J. Wooldridge, Jack E. Dibb, L Gregory Huey, R C. Hudman, S Turquety, L K. Emmons, F Flocke, Youhua Tang, Gregory R. Carmichael, Larry Horowitz

Earth Sciences

A comprehensive group of reactive nitrogen species (NO, NO2, HNO3, HO2NO2, PANs, alkyl nitrates, and aerosol-NO3) were measured over North America during July/August 2004 from the NASA DC-8 platform (0.1–12 km). Nitrogen containing tracers of biomass combustion (HCN and CH3CN) were also measured along with a host of other gaseous (CO, VOC, OVOC, halocarbon) and aerosol tracers. Clean background air as well as air with influences from biogenic emissions, anthropogenic pollution, biomass combustion, convection, lightning, and the stratosphere was sampled over the continental United States, the Atlantic, …


Surface And Lightning Sources Of Nitrogen Oxides Over The United States: Magnitudes, Chemical Evolution, And Outflow, R C. Hudman, D J. Jacob, S Turquety, Eric M. Leibensperger, L T. Murray, S Wu, A B. Gilliland, M A. Avery, T H. Bertram, William H. Brune, Ronald C. Cohen, Jack E. Dibb, F Flocke, A Fried, J S. Holloway, J A. Neuman, R Orville, A E. Perring, Xinrong Ren, G W. Sachse, H B. Singh, Aaron L. Swanson, Paul J. Wooldridge Jun 2007

Surface And Lightning Sources Of Nitrogen Oxides Over The United States: Magnitudes, Chemical Evolution, And Outflow, R C. Hudman, D J. Jacob, S Turquety, Eric M. Leibensperger, L T. Murray, S Wu, A B. Gilliland, M A. Avery, T H. Bertram, William H. Brune, Ronald C. Cohen, Jack E. Dibb, F Flocke, A Fried, J S. Holloway, J A. Neuman, R Orville, A E. Perring, Xinrong Ren, G W. Sachse, H B. Singh, Aaron L. Swanson, Paul J. Wooldridge

Earth Sciences

We use observations from two aircraft during the ICARTT campaign over the eastern United States and North Atlantic during summer 2004, interpreted with a global 3-D model of tropospheric chemistry (GEOS-Chem) to test current understanding of regional sources, chemical evolution, and export of NOx. The boundary layer NOx data provide top-down verification of a 50% decrease in power plant and industry NOx emissions over the eastern United States between 1999 and 2004. Observed NOx concentrations at 8–12 km altitude were 0.55 ± 0.36 ppbv, much larger than in previous U.S. aircraft campaigns (ELCHEM, SUCCESS, SONEX) though consistent with data from …


Ensuring Correctness Over Untrusted Private Database, Sarvjeet Singh, Sunil Prabhakar Jun 2007

Ensuring Correctness Over Untrusted Private Database, Sarvjeet Singh, Sunil Prabhakar

Department of Computer Science Technical Reports

No abstract provided.


Structure Pattern Analysis Using Term Rewriting And Clustering Algorithm, Xuezheng Fu Jun 2007

Structure Pattern Analysis Using Term Rewriting And Clustering Algorithm, Xuezheng Fu

Computer Science Dissertations

Biological data is accumulated at a fast pace. However, raw data are generally difficult to understand and not useful unless we unlock the information hidden in the data. Knowledge/information can be extracted as the patterns or features buried within the data. Thus data mining, aims at uncovering underlying rules, relationships, and patterns in data, has emerged as one of the most exciting fields in computational science. In this dissertation, we develop efficient approaches to the structure pattern analysis of RNA and protein three dimensional structures. The major techniques used in this work include term rewriting and clustering algorithms. Firstly, a …


Database Support For Probabilistic Attributes And Tuples, Sarvjeet Singh, Chris Mayfield, Rahul Shah, Sunil Prabhakar, Susanne E. Hambrusch, Reynold Cheng Jun 2007

Database Support For Probabilistic Attributes And Tuples, Sarvjeet Singh, Chris Mayfield, Rahul Shah, Sunil Prabhakar, Susanne E. Hambrusch, Reynold Cheng

Department of Computer Science Technical Reports

No abstract provided.


Query Selectivity Estimation For Uncertain Database, Sarvjeet Singh, Chris Mayfield, Rahul Shah, Sunil Prabhakar, Susanne E. Hambrusch Jun 2007

Query Selectivity Estimation For Uncertain Database, Sarvjeet Singh, Chris Mayfield, Rahul Shah, Sunil Prabhakar, Susanne E. Hambrusch

Department of Computer Science Technical Reports

No abstract provided.


Biomass Burning And Pollution Aerosol Over North America: Organic Components And Their Influence On Spectral Optical Properties And Humidification Response, A D. Clarke, Cameron Mcnaughton, V Kapustin, Yohei Shinozuka, S G. Howell, Jack E. Dibb, J Zhou, B Anderson, V Brekhovskikh, H Turner, M Pinkerton Jun 2007

Biomass Burning And Pollution Aerosol Over North America: Organic Components And Their Influence On Spectral Optical Properties And Humidification Response, A D. Clarke, Cameron Mcnaughton, V Kapustin, Yohei Shinozuka, S G. Howell, Jack E. Dibb, J Zhou, B Anderson, V Brekhovskikh, H Turner, M Pinkerton

Earth Sciences

Thermal analysis of aerosol size distributions provided size resolved volatility up to temperatures of 400°C during extensive flights over North America (NA) for the INTEX/ICARTT experiment in summer 2004. Biomass burning and pollution plumes identified from trace gas measurements were evaluated for their aerosol physiochemical and optical signatures. Measurements of soluble ionic mass and refractory black carbon (BC) mass, inferred from light absorption, were combined with volatility to identify organic carbon at 400°C (VolatileOC) and the residual or refractory organic carbon, RefractoryOC. This approach characterized distinct constituent mass fractions present in biomass burning and pollution plumes every 5–10 min. Biomass …


Hydrostratigraphy And Groundwater Migration Within Surficial Deposits At The North Lakes Wetland, Hillsborough County, Florida, Jason J. Laroche Jun 2007

Hydrostratigraphy And Groundwater Migration Within Surficial Deposits At The North Lakes Wetland, Hillsborough County, Florida, Jason J. Laroche

USF Tampa Graduate Theses and Dissertations

A wetland in west-central Florida was studied to characterize the local hydrostratigraphic configuration of surficial deposits overlying more-permeable limestones and conceptualize groundwater recharge. Eight continuous cores were drilled through the surficial deposits and partially into the underlying limestone. A total of 111 samples were extracted from the cores for laboratory sediment analyses and testing. The surficial deposits are roughly eight meters thick and made up of upper and lower clean-sand hydrostratigraphic layers (S1 and S3, respectively) separated by a low-permeability layer of clayey sand (S2). Also, a discontinuous low-permeability layer of clayey sand (S4) lies between S3 and the top …


Discrete Kato-Type Theorem On Inviscid Limit Of Navier-Stokes Flows, Wenfang Cheng, Xiaoming Wang Jun 2007

Discrete Kato-Type Theorem On Inviscid Limit Of Navier-Stokes Flows, Wenfang Cheng, Xiaoming Wang

Mathematics and Statistics Faculty Research & Creative Works

The inviscid limit of wall bounded viscous flows is one of the unanswered central questions in theoretical fluid dynamics. Here we present a somewhat surprising result related to numerical approximation of the problem. More precisely, we show that numerical solutions of the incompressible Navier-Stokes equations converge to the exact solution of the Euler equations at vanishing viscosity and vanishing mesh size provided that small scales of the order of U in the directions tangential to the boundary are not resolved in the scheme. Here is the kinematic viscosity of the fluid and U is the typical velocity taken to be …


Patterns Of Fish Diversity In A Mainstem Missouri River Reservoir And Associated Delta In South Dakota And Nebraska, Usa, Mark A. Kaemingk, Brian D.S. Graeb, Christopher W. Hoagstrom, David W. Willis Jun 2007

Patterns Of Fish Diversity In A Mainstem Missouri River Reservoir And Associated Delta In South Dakota And Nebraska, Usa, Mark A. Kaemingk, Brian D.S. Graeb, Christopher W. Hoagstrom, David W. Willis

School of Natural Resources: Faculty Publications

There is an expansive and expanding delta at the confluence of the Niobrara and Missouri Rivers in the Lewis and Clark Reservoir. The delta provides diverse aquatic habitat that is somewhat similar to the historic Missouri River and to remnant river habitats. As such, the delta may have relatively high fish species diversity compared to lentic reservoir habitats. To compare patterns of fish diversity between the delta and reservoir habitats, we collected fish in several nursery habitats in both areas using four gear types (seine, gill net, electrofisher and fyke net) on three occasions (July, August and September) in 2005. …


Note On The Emergence Of Large Scale Coherent Structure Under Small Scale Random Bombardments: The Discrete Case, Andrew Majda, Xiaoming Wang Jun 2007

Note On The Emergence Of Large Scale Coherent Structure Under Small Scale Random Bombardments: The Discrete Case, Andrew Majda, Xiaoming Wang

Mathematics and Statistics Faculty Research & Creative Works

We continue our study on mathematical justification of the emergence of large-scale coherent structure in a two-dimensional fluid system under small scale random bombardments. We treat the case of small-scale random bombardments at discrete times which is different from our earlier work [Commun. Pure Appl. Math. 59, 467 (2006)], where we approximated the small-scale random kicks by a continuous in time random process. in the absence of geophysical effects, the large-scale structure emerging out of the small-scale random forcing is the same as the case of continuous in time forcing that we studied before. © 2007 American Institute of Physics.


Controlling Surface Morphologies By Time-Delayed Feedback, M. Block, Beate Schmittmann, E. Schöll Jun 2007

Controlling Surface Morphologies By Time-Delayed Feedback, M. Block, Beate Schmittmann, E. Schöll

Beate Schmittmann

We propose a method to control the roughness of a growing surface via a time-delayed feedback scheme. The method is very general and can be applied to a wide range of nonequilibrium growth phenomena, from solid-state epitaxy to tumor growth. Possible experimental realizations are suggested. As an illustration, we consider the Kardar-Parisi-Zhang equation [Phys. Rev. Lett. 56, 889 (1986)] in 1+1 dimensions and show that the effective growth exponent of the surface width can be stabilized at any desired value in the interval [0.25, 0.33], for a significant length of time.