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Hierarchical Multiple Bit Clusters And Patterned Media Enabled By Novel Nanofabrication Techniques - High Resolution Electron Beam Lithography And Block Polymer Self Assembly, Qijun Xiao 2010 University of Massachusetts - Amherst

Hierarchical Multiple Bit Clusters And Patterned Media Enabled By Novel Nanofabrication Techniques - High Resolution Electron Beam Lithography And Block Polymer Self Assembly, Qijun Xiao

Open Access Dissertations

This thesis discusses the full scope of a project exploring the physics of hierarchical clusters of interacting nanomagnets. These clusters may be relevant for novel applications such as multilevel data storage devices. The work can be grouped into three main activities: micromagnetic simulation, fabrication and characterization of proof-ofconcept prototype devices, and efforts to scale down the structures by creating the hierarchical structures with the aid of diblock copolymer self assembly. Theoretical micromagnetic studies and simulations based on Landau-Lifshitz- Gilbert (LLG) equation were conducted on nanoscale single domain magnetic entities. For the simulated nanomagnet clusters with perpendicular uniaxial anisotropy, the simulation ...


Dark Matter Halos: Assembly, Clustering And Sub-Halo Accretion, Yun Li 2010 University of Massachusetts - Amherst

Dark Matter Halos: Assembly, Clustering And Sub-Halo Accretion, Yun Li

Open Access Dissertations

I carried out systematic studies on the assembly history of dark matter halos, using numerical simulations and semi-analytical methods. First, I look into dark halo mass assembly history. I confirmed that the halo mass assembly is divided into a fast accretion phase and a slow accretion phase. These two phases are found to be separated by the epoch when the dark halo potential reaches its maximum. The fast accretion phase is dominated by mergers, especially major mergers; the slow accretion phase is dominated by slow mass accretion. Each halo experiences about 3±2 major mergers since its main progenitor had ...


Basis Construction And Utilization For Markov Decision Processes Using Graphs, Jeffrey Thomas Johns 2010 University of Massachusetts - Amherst

Basis Construction And Utilization For Markov Decision Processes Using Graphs, Jeffrey Thomas Johns

Open Access Dissertations

The ease or difficulty in solving a problemstrongly depends on the way it is represented. For example, consider the task of multiplying the numbers 12 and 24. Now imagine multiplying XII and XXIV. Both tasks can be solved, but it is clearly more difficult to use the Roman numeral representations of twelve and twenty-four. Humans excel at finding appropriate representations for solving complex problems. This is not true for artificial systems, which have largely relied on humans to provide appropriate representations. The ability to autonomously construct useful representations and to efficiently exploit them is an important challenge for artificial intelligence ...


Generalized Instruction Selector Generation: The Automatic Construction Of Instruction Selectors From Descriptions Of Compiler Internal Forms And Target Machines, Timothy David Richards 2010 University of Massachusetts - Amherst

Generalized Instruction Selector Generation: The Automatic Construction Of Instruction Selectors From Descriptions Of Compiler Internal Forms And Target Machines, Timothy David Richards

Open Access Dissertations

One of the most difficult tasks a compiler writer faces is the construction of the instruction selector. The instruction selector is that part of the compiler that translates compiler intermediate representation (IR) into instructions for a target machine. Unfortunately, implementing an instruction selector “by hand” is a difficult, time consuming, and error prone task. The details of both the IR and target instruction set must be carefully considered in order to generate correct and efficient code. This, in turn, requires an expert in both the compiler internals as well as the target machine. Even an expert, however, can implement an ...


Existence, Stability, And Dynamics Of Solitary Waves In Nonlinear Schroedinger Models With Periodic Potentials, Kody John Hoffman Law 2010 University of Massachusetts - Amherst

Existence, Stability, And Dynamics Of Solitary Waves In Nonlinear Schroedinger Models With Periodic Potentials, Kody John Hoffman Law

Open Access Dissertations

The focus of this dissertation is the existence, stability, and resulting dynamical evolution of localized stationary solutions to Nonlinear Schr¨odinger (NLS) equations with periodic confining potentials in 2(+1) dimensions. I will make predictions about these properties based on a discrete lattice model of coupled ordinary differential equations with the appropriate symmetry. The latter has been justified by Wannier function expansions in a so-called tight-binding approximation in the appropriate parametric regime. Numerical results for the full 2(+1)-D continuum model will be qualitatively compared with discrete model predictions as well as with nonlinear optics experiments in optically induced ...


A Discriminative Model For Semi-Supervised Learning, Maria-Florina Balcan, Avrim Blum 2010 Georgia Institute of Technology

A Discriminative Model For Semi-Supervised Learning, Maria-Florina Balcan, Avrim Blum

Computer Science Department

Supervised learning—that is, learning from labeled examples—is an area of Machine Learning that has reached substantial maturity. It has generated general-purpose and practically successful algorithms and the foundations are quite well understood and captured by theoretical frameworks such as the PAC-learning model and the Statistical Learning theory framework. However, for many contemporary practical problems such as classifying web pages or detecting spam, there is often additional information available in the form ofunlabeled data, which is often much cheaper and more plentiful than labeled data. As a consequence, there has recently been substantial interest in semi-supervised learning—using ...


Our Places To Tell Stories: Preliminary Program Springs Preserve, Public Lands Institute 2010 Public Lands Institute

Our Places To Tell Stories: Preliminary Program Springs Preserve, Public Lands Institute

Our Places to Tell Stories

Our Places Tell Stories is an innovative conference for educators and others working at public lands, schools, nature centers, museums, zoos, aquaria, and all nature and heritage rich places.

This list of presentations represents a preliminary program of sessions. A final program will be emailed to all registrants prior to the conference. Thank you for your interest, and we look forward to seeing you at the Springs!


Doe Request For Information (Rfi) De-Foa-0000153 Pv Manufacturing Initiative: Summary Report, National Renewable Energy Laboratory 2010 University of Nevada, Las Vegas

Doe Request For Information (Rfi) De-Foa-0000153 Pv Manufacturing Initiative: Summary Report, National Renewable Energy Laboratory

Publications (E)

Clean Cities hosts a collection of tools on the exploring concepts for a “PV Manufacturing Initiative” to facilitate the development of a strong photovoltaic (PV) manufacturing industry in the United States. As an integral part this effort, and to inform the creation of a new funding opportunity in this area, DOE sought feedback from the PV industry.

This document summarizes the results of the PV Manufacturing Request for Information (RFI), DE-FOA-0000153. (See Attachment 1.) The RFI was posted on http://www.grants.gov on 4 September 2009 and the NREL Web site on 9 September 2009. Respondents were asked to ...


Updated U.S. Geothermal Supply Curve, C. Augustine, K. R. Young, A. Anderson 2010 National Renewable Energy Laboratory

Updated U.S. Geothermal Supply Curve, C. Augustine, K. R. Young, A. Anderson

Publications (E)

This paper documents the approach used to update the U.S. geothermal supply curve. The geothermal supply curve analysis undertaken in this study estimates the supply of electricity generation potential from geothermal resources in the United States and the levelized cost of electricity (LCOE), capital costs, and operating and maintenance costs associated with developing these geothermal resources. The supply curve data are used as input to annual reporting by the U.s. Department of Energy (DOE) under the Government Performance and Results Act of 1993, the DOE portfolio development support processes, and market penetration models in support of other DOE ...


Report On The U.S. Doe Geothermal Technologies Program's 2009 Risk Analysis, K. R. Young, C. Augustine, A. Anderson 2010 National Renewable Energy Laboratory

Report On The U.S. Doe Geothermal Technologies Program's 2009 Risk Analysis, K. R. Young, C. Augustine, A. Anderson

Publications (E)

The U.S. Department of Energy (DOE) Geothermal Technologies Program (GTP or “the Program”) conducted a detailed risk analysis of their annual research, development, and demonstration (RD&D) portfolio. The Program worked with the National Renewable Energy Laboratory (NREL) to implement a probabilistic risk analysis of the GTP-sponsored RD&D, primarily enhanced geothermal systems (EGS) in accordance with Program budget authority. EGS technologies are in the early stages of development, and GTP-sponsored, multi-year demonstration projects are now underway to demonstrate technical feasibility, reduce risk for industry, and improve EGS best practices. The risk analysis examined estimates of improvement potential for ...


Characterization Of Winds Through The Rotor Plane Using A Phased Array Sodar And Recommendations For Future Work, Regina Anne Deola 2010 Sandia National Laboratories

Characterization Of Winds Through The Rotor Plane Using A Phased Array Sodar And Recommendations For Future Work, Regina Anne Deola

Publications (E)

Portable remote sensing devices are increasingly needed to cost effectively characterize the meteorology at a potential wind energy site as the size of modern wind turbines increase. A short term project co-locating a Sound Detection and Ranging System (SODAR) with a 200 meter instrumented meteorological tower at the Texas Tech Wind Technology Field Site was performed to collect and summarize wind information through an atmospheric layer typical of utility scale rotor plane depths. Data collected identified large speed shears and directional shears that may lead to unbalanced loads on the rotors. This report identifies suggestions for incorporation of additional data ...


Combined Single-Molecule Photon-Stamping Spectroscopy And Femtosecond Transient Absorption Spectroscopy Studies Of Interfacial Electron Transfer Dynamics, Lijun Guo, Yuanmin Wang, H. Peter Lu 2010 Bowling Green State University - Main Campus

Combined Single-Molecule Photon-Stamping Spectroscopy And Femtosecond Transient Absorption Spectroscopy Studies Of Interfacial Electron Transfer Dynamics, Lijun Guo, Yuanmin Wang, H. Peter Lu

Chemistry Faculty Publications

The inhomogeneous interfacial electron transfer (IET) dynamics of 9-phenyl-2,3,7-trihydroxy-6-fluorone (PF)-sensitized TiO2 nanoparticles (NPs) has been probed by a single-molecule photon-stamping technique as well as ensemble-averaged femtosecond transient absorption spectroscopy. The forward electron transfer (FET) time shows a broad distribution at the single-molecule level, indicating the inhomogeneous interactions and ET reactivity of the PF/TiO2 NP system. The broad distribution of the FET time is measured to be 0.4 ± 0.1 ps in the transient absorption and picoseconds to nanoseconds in the photon-stamping measurements. The charge recombination time, having a broad distribution at the single-molecule level, clearly ...


Bosonic Analog Of The Klein Paradox, R E. Wagner, M R. Ware, Q Su, Rainer Grobe 2010 Illinois State University

Bosonic Analog Of The Klein Paradox, R E. Wagner, M R. Ware, Q Su, Rainer Grobe

Faculty publications – Physics

The standard Klein paradox describes how an incoming electron scatters off a supercritical electrostatic barrier that is so strong that it can generate electron- positron pairs. This fermionic system has been widely discussed in textbooks to illustrate some of the discrepancies between quantum mechanical and quantum field theoretical descriptions for the pair creation process. We compare the fermionic dynamics with that of the corresponding bosonic system. We point out that the direct counterpart of the Pauli exclusion principle (the central mechanism to resolve the fermionic Klein paradox) is stimulated emission, which leads to the resolution of the analogous bosonic paradox.


Gene Expression Profiling Of The Short-Term Adaptive Response To Acute Caloric Restriction In Liver And Adipose Tissues Of Pigs Differing In Feed Efficiency, Sender Lkhagvadorj, Long Qu, Weiguo Cai, Oliver P. Couture, C. Richard Barb, Gary J. Hausman, Dan Nettleton, Lloyd L. Anderson, Jack C. M. Dekkers, Christopher K. Tuggle 2010 Iowa State University

Gene Expression Profiling Of The Short-Term Adaptive Response To Acute Caloric Restriction In Liver And Adipose Tissues Of Pigs Differing In Feed Efficiency, Sender Lkhagvadorj, Long Qu, Weiguo Cai, Oliver P. Couture, C. Richard Barb, Gary J. Hausman, Dan Nettleton, Lloyd L. Anderson, Jack C. M. Dekkers, Christopher K. Tuggle

Animal Science Publications

Residual feed intake (RFI) is a measure of feed efficiency, in which low RFI denotes improved feed efficiency. Caloric restriction (CR) is associated with feed efficiency in livestock species and to human health benefits, such as longevity and cancer prevention. We have developed pig lines that differ in RFI, and we are interested in identifying the genes and pathways that underlie feed efficiency. Prepubertal Yorkshire gilts with low RFI (n = 10) or high RFI (n = 10) were fed ad libitum or fed at restricted intake of 80% of maintenance energy requirements for 8 days. We measured serum metabolites and hormones ...


Incubation Behavior Of The Mountain Plover, Paul Daniel Blom Skrade, Stephen J. Dinsmore 2010 Iowa State University

Incubation Behavior Of The Mountain Plover, Paul Daniel Blom Skrade, Stephen J. Dinsmore

Natural Resource Ecology and Management Conference Papers, Posters and Presentations

e rapid multi-clutch mating system of the Mountain Plover (Charadrius montanus) is an opportunity to examine sex-specific differences in uniparental care. We monitored nocturnal incubation activity in Phillips County, Montana using video recordings and temperature data-loggers. Possible differences in activity were modeled using the duration of nest departures of incubating adults. We examined the effects of sex, time of departure, nest age, day of season, maximum temperature, precipitation the previous day, and year on nest departures. We recorded 857 hours of video at 25 nests and >10,000 hours of temperature data from 142 nests during the 2006-2008 breeding seasons ...


Microscopic Formulation Of The Zimm-Bragg Model For The Helix-Coil Transition, A. V. Badasyan, A. Giacometti, Y. S. Mamasakhlisov, V. F. Morozov, Albert S. Benight 2010 Portland State University

Microscopic Formulation Of The Zimm-Bragg Model For The Helix-Coil Transition, A. V. Badasyan, A. Giacometti, Y. S. Mamasakhlisov, V. F. Morozov, Albert S. Benight

Chemistry Faculty Publications and Presentations

A microscopic spin model is proposed for the phenomenological Zimm-Bragg model for the helix-coil transition in biopolymers. This model is shown to provide the same thermophysical properties of the original Zimm-Bragg model and it allows a very convenient framework to compute statistical quantities. Physical origins of this spin model are made transparent by an exact mapping into a one-dimensional Ising model with an external field. However, the dependence on temperature of the reduced external field turns out to differ from the standard one-dimensional Ising model and hence it gives rise to different thermophysical properties, despite the exact mapping connecting them ...


Making Our Communities Greener: A Case Study Of Promoting Biogas Energy By Tongwei Evergreen Libraries In China, Wenjie Zhou, Tim J. Zou, Elaine X. Dong 2010 University of Arkansas, Fayetteville

Making Our Communities Greener: A Case Study Of Promoting Biogas Energy By Tongwei Evergreen Libraries In China, Wenjie Zhou, Tim J. Zou, Elaine X. Dong

University Libraries Faculty Publications and Presentations

Promoting the consumption of new energies, particularly of biogas, in rural areas is a strategic initiative of the Chinese government. The government has incorporated this initiative into many of its rural development plans. Likewise, Tongwei Evergreen Libraries (TEL, 通渭青树图书馆) has also integrated ideas of the initiative into its library services. This paper describes the Biogas Promotion Program (BPP) that TEL implemented, discusses the BPP model and roles of TEL in the program, and analyzes the initial results of the program through surveying local farmers. A survey was developed for this assessment study. The survey results show that the government biogas ...


Magnetic Properties Of The Quasi-Two-Dimensional S=1/2 Heisenberg Antiferromagnet [Cu(Pyz)(2)(Hf2)]Pf6, E Cizmar, S A. Zvyagin, R Beyer, M Uhlarz, M Ozerov, Y Skourski, Jamie L. Manson, J A. Schlueter, J Wosnitza 2010 Eastern Washington University

Magnetic Properties Of The Quasi-Two-Dimensional S=1/2 Heisenberg Antiferromagnet [Cu(Pyz)(2)(Hf2)]Pf6, E Cizmar, S A. Zvyagin, R Beyer, M Uhlarz, M Ozerov, Y Skourski, Jamie L. Manson, J A. Schlueter, J Wosnitza

Chemistry and Biochemistry Faculty Publications

We report on high-field magnetization, specific heat, and electron-spin-resonance (ESR) studies of the quasi-two-dimensional spin-1/2 Heisenberg antiferromagnet [Cu(pyz)(2)(HF2)]PF6. The frequency-field diagram of ESR modes below T-N=4.38 K is described in the frame of the mean-field theory, confirming a collinear magnetic structure with an easy-plane anisotropy. The obtained results allowed us to determine the anisotropy/exchange interaction ratio, A/J=0.003, and the upper limit for the interplane/intraplane exchange interaction ratio, J'/J=1/16. It is argued that despite the onset of three-dimensional long-range magnetic ordering the magnetic properties of this ...


A Stochastic Model Of Cell Cycle Desynchronization, Peter Olofsson, Thomas O. McDonald 2010 Trinity University

A Stochastic Model Of Cell Cycle Desynchronization, Peter Olofsson, Thomas O. Mcdonald

Mathematics Faculty Research

A general branching process model is suggested to describe cell cycle desynchronization. Cell cycle phase times are modeled as random variables and a formula for the expected fraction of cells in S phase as a function of time is established. The model is compared to data from the literature and is also compared to previously suggested deterministic and stochastic models.


Total Maximum Daily Loads (Tmdls) For Phosphorus In Buck, Long, And Cranberry Ponds Monroe County, New York, The Cadmus Group 2010 The College at Brockport: State University of New York

Total Maximum Daily Loads (Tmdls) For Phosphorus In Buck, Long, And Cranberry Ponds Monroe County, New York, The Cadmus Group

Government Documents

Buck, Long, and Cranberry Ponds (WI/PWL IDs 0301-0017, 0301-0015, and 0301-0016, respectively) are located along the Lake Ontario shoreline in the Town of Greece, within Monroe County, New York. Over the past couple of decades, the ponds have experienced degraded water quality that has reduced the ponds’ recreational and aesthetic value. In particular, recreational suitability has become less favorable due to excessive weed growth in the ponds. All three ponds have high concentrations of total phosphorus. Long Pond has the highest concentrations followed by Cranberry and then Buck Pond.

A variety of phosphorus sources contribute to the poor water ...


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