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Articles 1231 - 1260 of 2568

Full-Text Articles in Physical Sciences and Mathematics

Completeness Of The Leibniz Field And Rigorousness Of Infinitesimal Calculus, James F. Hall, Todor D. Todorov Aug 2011

Completeness Of The Leibniz Field And Rigorousness Of Infinitesimal Calculus, James F. Hall, Todor D. Todorov

Mathematics

We present a characterization of the completeness of the field of real numbers in the form of a collection of ten equivalent statements borrowed from algebra, real analysis, general topology and non-standard analysis. We also discuss the completeness of non-Archimedean fields and present several examples of such fields. As an application we exploit one of our results to argue that the Leibniz infinitesimal calculus in the 18th century was already a rigorous branch of mathematics – at least much more rigorous than most contemporary mathematicians prefer to believe. By advocating our particular historical point of view, we hope to …


Manova: Type I Error Rate Analysis, Christopher Dau Wei Ling Aug 2011

Manova: Type I Error Rate Analysis, Christopher Dau Wei Ling

Statistics

No abstract provided.


An Agent Facilitated Design Conversation System For Facilitating The Designer In Creative Thinking In Architectural Design, Geeta Arjun, Jim Plume Aug 2011

An Agent Facilitated Design Conversation System For Facilitating The Designer In Creative Thinking In Architectural Design, Geeta Arjun, Jim Plume

Collaborative Agent Design (CAD) Research Center

The paper discusses a current research that investigates if a computer aided conversation system can be created to support the human thought process in the early stages of architectural design. It argues that design conversations are an essential premise for designing, especially at the early stages, when the designer has to brainstorm ideas to generate creative conceptual solution-conjectures. The paper also argues that design knowledge is mainly dependent on a designer’s experiences. But experiential knowledge, stored in the long term memory is difficult to recall. Based on these arguments, an agent-based knowledge system, Design Thinker, is designed to allow for …


The Role Of Entrepreneurship, Innovation, And Intuition, Jens Pohl Aug 2011

The Role Of Entrepreneurship, Innovation, And Intuition, Jens Pohl

Collaborative Agent Design (CAD) Research Center

In recognizing the importance of entrepreneurship and innovation as the principal drivers of economic growth, this paper focuses on the human attributes that govern the behavior of the entrepreneur and the societal perceptions that influence the human environment in which the entrepreneur operates. Foremost among these human attributes is the experience-based nature of the human cognitive system that prepares us well for dealing with events that are closely related to our past experience, but forces us to learn by failure as we apply past methods to new situations. In particular, the paper discusses the difficulties that the human dependence on …


Semantic Transformation Of Search Requests For Improving The Results Of Web Search, Vladimir A. Fomichov, Anton V. Kirillov Aug 2011

Semantic Transformation Of Search Requests For Improving The Results Of Web Search, Vladimir A. Fomichov, Anton V. Kirillov

Collaborative Agent Design (CAD) Research Center

The paper describes a new method of constructing semantic expansions of search requests for improving the results of Web search. This method is based on the theory of K-representations -a new theory of designing semantic-syntactic analyzers of natural language texts with the broad use of formal means for representing input, intermediary, and output data. The current version of the theory is set forth in a monograph published by Springer in 2010. The stated approach is implemented with the help of the Web programming language Java: an experimental search system AOS (Aspect Oriented Search) has been developed.


Technology Assessment: Applied Infocyber Scenarios, John F. Halldane Aug 2011

Technology Assessment: Applied Infocyber Scenarios, John F. Halldane

Collaborative Agent Design (CAD) Research Center

CADRC and KML present an urgent need for analyzing the enormous volume of digital data in people centered applications. Adaptive knowledge-based collaborative agents were suggested. Amatrix for collaborative control, monitoring and management was outlined (Halldane Aug 2006) based on inline and crossline management principles. This introduced channels describing the technology and context, nodes of common parameters or attributes to link with other channels through secure analytical gates, then parallel tracks of meaningful criteria from performance, specifications, monitoring, to priorities. This is now applied in analytical scenarios to compare channels and tracks for assessing technology against meaningful infocyber tracks (Figure 1). …


Preconference Proceedings Of The Focus Symposium On Intelligent Information Management Systems, Jens G. Pohl Aug 2011

Preconference Proceedings Of The Focus Symposium On Intelligent Information Management Systems, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

No abstract provided.


An Intelligent Supply Chain Planning And Execution Environment, Jens Pohl Aug 2011

An Intelligent Supply Chain Planning And Execution Environment, Jens Pohl

Collaborative Agent Design (CAD) Research Center

Logistic planning and execution processes in a supply-chain are subject to a high level of complexity because of the number of parties and issues involved, the number of relationships that exist among them, and the dynamic nature of the execution environment. The large volume of data flowing through a sizable computer-based logistic planning and execution management environment that is based on rote data-processing principles tends to overwhelm the human users. As a result many opportunities for improving the efficiency of supply-chain processes and thereby reducing costs are overlooked by the human users, who are forced into a reactive mode. Similar …


Isolation Of Obligately Alkaliphilic Magnetotactic Bacteria From Extremely Alkaline Environments, Christopher T. Lefevre, Richard B. Frankel, Mihály Pósfai, Tanya Prozorov, Dennis A. Bazylinski Aug 2011

Isolation Of Obligately Alkaliphilic Magnetotactic Bacteria From Extremely Alkaline Environments, Christopher T. Lefevre, Richard B. Frankel, Mihály Pósfai, Tanya Prozorov, Dennis A. Bazylinski

Physics

Large numbers of magnetotactic bacteria were discovered in mud and water samples collected from a number of highly alkaline aquatic environments with pH values of ~ 9.5. These bacteria were helical in morphology and biomineralized chains of bullet-shaped crystals of magnetite and were present in all the highly alkaline sites sampled. Three strains from different sites were isolated and cultured and grew optimally at pH 9.0–9.5 but not at 8.0 and below, demonstrating that these organisms truly require highly alkaline conditions and are not simply surviving/growing in neutral pH micro-niches in their natural habitats. All strains grew anaerobically through the …


Characterization Of Uranium Species In Sediments Under Iron And Sulfate Reducing Conditions Using Synchrotron-Based Techniques, Don Q. Pham, John Bargar Aug 2011

Characterization Of Uranium Species In Sediments Under Iron And Sulfate Reducing Conditions Using Synchrotron-Based Techniques, Don Q. Pham, John Bargar

STAR Program Research Presentations

Uranium is one of the most common and problematic contaminants at legacy Department of Energy sites. Groundwater contamination is particularly problematic because it occurs at depth, is present in large volumes, and cannot be easily accessed for clean-up. One method of remediation being investigated is the bioreduction of soluble U(VI) to insoluble U(IV) complexes through the in-situ stimulation of metal-reducing bacteria. Understanding the structure of these uranium complexes can help us determine their fate and stability in groundwater and map out the biological process of uranium reduction by metal-reducing bacteria. In this study, we used the synchrotron-based techniques, X-ray absorption …


Exploring Methods For Earthquake Prediction: The Effects Of Water On The Flow Of Stress-Activated Electric Currents In Igneous Rocks, Aaron M. Jahoda, Friedemann T. Freund Aug 2011

Exploring Methods For Earthquake Prediction: The Effects Of Water On The Flow Of Stress-Activated Electric Currents In Igneous Rocks, Aaron M. Jahoda, Friedemann T. Freund

STAR Program Research Presentations

Much of the devastation and damage of earthquakes can be attributed to the fact that they occur suddenly and without much warning, which limits the ability of people to evacuate and/or properly prepare. One method, however, that might be used to predict seismic events is the generation of electric currents in rocks when stresses are applied. It is observed in this research that the application of direct force onto samples of igneous rock causes the rocks to generate a measurable current, which is attributed to positive-hole charges moving within the oxygen sub-lattice. Because large and changing forces are acted upon …


Quantitative Characterization Of Microstructure Features For 1st Generation Advanced High Strength Steels, Margarita Vidrio, Ellen Liu, Donsheng Li, Kyoo Sil Choi, Xin Sun Aug 2011

Quantitative Characterization Of Microstructure Features For 1st Generation Advanced High Strength Steels, Margarita Vidrio, Ellen Liu, Donsheng Li, Kyoo Sil Choi, Xin Sun

STAR Program Research Presentations

The role of Advanced High Strength Steels (AHSS) in the automotive industry is important because of its affordability and excellent mechanical properties. The 1st generation of AHSS achieves its preferred combination of strength and ductility by embedding harder martensite grains into softer ferritic matrix. Ductility and strength of these steels are important to safety, formability, application, and life. However, a noticeable degree of inconsistent forming behaviors has been observed in the 1st generation AHSS in production, which seems to be related to the microstructure-level inhomogeneity. The objective of this project is to grain fundamental understandings on how different microstructure level …


Rehabilitation Of Srrl Aerosol Optical Depth Photometer Data, Elin Deeb, Daryl Myers, Afshin Andreas Aug 2011

Rehabilitation Of Srrl Aerosol Optical Depth Photometer Data, Elin Deeb, Daryl Myers, Afshin Andreas

STAR Program Research Presentations

NREL’s Solar Radiation Research Laboratory (SRRL) utilizes a Prede POM-01 Photometer to collect aerosol optical depth (AOD) information, necessary for determining the performance of solar collector systems. Inconsistencies and errors exist in SRRL’s AOD data due to errors in the calibration factors as well as the data reduction algorithms. Langley plots of five of the channels were performed to calibrate the necessary constants for AOD calculations. Clear sky data was determined based on the ratio of direct to global radiation and on the scatter between morning and afternoon TWC 500 nm photometer (an NREL custom photometer) data. Plots of calculated …


Remote Sensing Analysis For Salinity Management Of Seasonal Wetlands, Debra L. S. Miller, Nigel W.T. Quinn Aug 2011

Remote Sensing Analysis For Salinity Management Of Seasonal Wetlands, Debra L. S. Miller, Nigel W.T. Quinn

STAR Program Research Presentations

A 170,000 wetland complex, including wetlands managed by the Grassland Water District (GWD), are located in California’s Central Valley in Merced County. The GWD is divided into North and South areas which are further divided into subareas. Historically, these wetlands were created by annual floods along the San Joaquin River that inundated the floodplain and created habitat for native wildlife, and over-wintering waterfowl. Today, these wetland areas are managed artificially with water supply provided from the Delta. Data from a real-time sensor network located along channels and at the inlets and outlets to and from individual ponds is being used …


Effects Of Mechanical Ventilation Rates On Indoor Formaldehyde Levels, Thuy Nguyen, Henry Willem Aug 2011

Effects Of Mechanical Ventilation Rates On Indoor Formaldehyde Levels, Thuy Nguyen, Henry Willem

STAR Program Research Presentations

Airtight construction of energy efficient homes increasingly limits the indoor and outdoor air exchange. Consequently, Volatile Organic Compounds (VOC) and Formaldehyde can accumulate to toxic levels. Formaldehyde is an eye and respiratory irritant suspected as one of the inducing agents of asthma. Exposure to Formaldehyde has been linked to nasopharyngeal cancer and leukemia. This study evaluated the effects of increasing ventilation rates through Energy Recovery Ventilator (ERV) in a new home. The study objective is to determine the effects of increasing ventilation rates on the concentrations of Formaldehyde and the associated emission rates. The results indicate that increasing ventilation rates …


Supernova Remnants And Cosmic Ray Acceleration Mechanisms, Ariel L. Simons, Yasunobu Uchiyama Aug 2011

Supernova Remnants And Cosmic Ray Acceleration Mechanisms, Ariel L. Simons, Yasunobu Uchiyama

STAR Program Research Presentations

Supernova remnants (SNRs) are considered to be the primary energy source of galactic-origin cosmic rays. Within this prediction exist two models, leptonic and hadronic, to explain the acceleration of charged particles up to a PeV in energy. Using data from the Fermi Gamma-ray Space Telescope (FGST) each model is expected to produce a distinct spectral energy distribution (SED) over a photon energy range of 100MeV to 100GeV. This analysis is focused on the methods for generating SEDs for the SNR Cassiopeia A and how they can be used to constrain the likelihood of either acceleration model.


A Study Of Ozone At Railroad Valley, Nv And Trinidad Head, Ca, Sarah L. Salazar, Laura T. Iraci, Emma L. Yates Aug 2011

A Study Of Ozone At Railroad Valley, Nv And Trinidad Head, Ca, Sarah L. Salazar, Laura T. Iraci, Emma L. Yates

STAR Program Research Presentations

A STUDY OF OZONE AT RAILROAD VALLEY, NV and TRINIDAD HEAD, CA

Ozone (Oᴣ) is a form of oxygen that protects the planet Earth from deadly ultraviolet rays emitted by the sun; without this triatomic molecule high in the atmosphere, life processes on the planet would be impossible. Ozone is an air pollutant and toxic in the lowest part of the atmosphere, and inhaling it could cause permanent damage to animals’ respiratory system. Long term exposure to high concentration of ozone has been linked with the development of asthma in children. Because of its complicated role in our atmosphere, scientists …


Spectroscopic Properties Of Lanthanide (Iii) Compounds In Aqueous And Ionic Media, Orissa A. Burghard, Sayandev Chatterjee, Zheming Wang, Samuel A. Bryan Aug 2011

Spectroscopic Properties Of Lanthanide (Iii) Compounds In Aqueous And Ionic Media, Orissa A. Burghard, Sayandev Chatterjee, Zheming Wang, Samuel A. Bryan

STAR Program Research Presentations

Lanthanide containing materials are receiving increasing attention due to their wide range of potential applications including bioanalytical imaging, dye-sensitized solar cells, nano-biotechnology and catalysis. The unique spectroscopic properties (intense and sharp emission bands with high color purity and high quantum efficiency) of lanthanides make them strong candidates for use as bio-markers or selective detectors. The attractiveness of lanthanides as future imaging agents as well as recent interest in their potential use in biological media has increased the need to understand the behavior of lanthanides in the presence of other ions or in ionic media.

The complexity of the biological media …


Identifying Species In Mass Spectra Using Principal Component Analysis (Pca), Bradley Powers, Bernice Mills Aug 2011

Identifying Species In Mass Spectra Using Principal Component Analysis (Pca), Bradley Powers, Bernice Mills

STAR Program Research Presentations

Many materials outgas as they are heated in a vacuum, compromising a sealed vacuum if they cannot be gettered. Our goal is to be able to identify which molecules are emitted and at what temperature. Determining specific species from the fragments produced in the mass spectrometer is extremely difficult since there is always more than one species outgassed at any time. We have chosen to use PCA because it has been used previously with mass spectral data. The commercial PCA software we used was unable to separate the spectra into pure, or almost pure, species. Other strategies for interpreting the …


Effects Of High-Density, Short-Duration Planned Livestock Grazing On Soil Carbon Sequestration Potentials In A Coastal California Mixed Grassland, Kristina Michelle Wolf, Marc Horney, Brent Hallock, Robert T. Rutherford, Anthony T. O'Geen, Royce Larsen, William Plummer Aug 2011

Effects Of High-Density, Short-Duration Planned Livestock Grazing On Soil Carbon Sequestration Potentials In A Coastal California Mixed Grassland, Kristina Michelle Wolf, Marc Horney, Brent Hallock, Robert T. Rutherford, Anthony T. O'Geen, Royce Larsen, William Plummer

Master's Theses

Planned grazing management in rangelands may improve carbon sequestration potential of soils by increasing plant biomass and the rate of nutrient cycling, which might mitigate global warming. The effects of high-intensity, short-duration planned grazing of sheep on several soil and ecosystem properties were investigated on a mixed grassland in San Luis Obispo, CA. The objectives of this study were to (a) identify soil properties related to soil C sequestration in rangelands; (b) determine if planned grazing improved soil carbon sequestration; (c) quantify changes in identified variables in grazed and rested plots; and (d) analyze any changes in plant species composition …


Effect Of Au Content On Microstructural Evolution Of Snagcu Solder Joints That Undergo Isothermal Aging And Reliability Testing, Patrick J. Hyland Aug 2011

Effect Of Au Content On Microstructural Evolution Of Snagcu Solder Joints That Undergo Isothermal Aging And Reliability Testing, Patrick J. Hyland

Master's Theses

Electronics, especially, printed circuit boards (PCBs) are a widespread technology. Metal coatings or “surface finishes” are often added to PCB board pads and component leads during manufacturing to improve their performance. Electroplated nickel/gold over copper is a popular surface finish for printed circuit boards and component leads. The presence of gold in solder joints, however, is known to have detrimental effects referred to as gold embrittlement. It is generally understood that tin-lead solder joints with less than 3 weight percent (wt%) of gold will not experience reliability issues. The acceptable level of gold in lead-free solder joints, however, is less …


Trends In Web Typography, Heather Mcintosh Aug 2011

Trends In Web Typography, Heather Mcintosh

Graphic Communication

No abstract provided.


Morphology Changes In Pcpdtbt:Pcbm And P3ht:Pcpdtbt:Pcbm And Its Effect On Polymer Solar Cell Performance, Galen David Cauble Aug 2011

Morphology Changes In Pcpdtbt:Pcbm And P3ht:Pcpdtbt:Pcbm And Its Effect On Polymer Solar Cell Performance, Galen David Cauble

Physics

Polymer solar cell morphology is sensitive to both heat and time. By thermally annealing polymer solar cells the morphology of the devices can be altered causing immediate changes in device performance. Blending PCPDTBT:PCBM with P3HT:PCPDTBT combines the absorption characteristics of each to create a more even absorption spectrum. Subjecting PCPDTBT:PCBM, and P3HT:PCPDTBT:PCBM polymer solar cells to thermal annealing as well as recording device performance through time has shown that P3HT:PCPDTBT:PCBM devices react positively to thermal annealing (increasing from 0.8% to 1.4%) while PCPDTBT:PCBM devices have varied reactions. Furthermore, the P3HT:PCPDTBT:PCBM devices have achieved efficiencies of 1.6% in AM 1.5 compared …


Biaxial Smectic-A Phase And Its Possible Misidentification As A Smectic-CΑ* Phase, Karl Saunders Jul 2011

Biaxial Smectic-A∗ Phase And Its Possible Misidentification As A Smectic-CΑ* Phase, Karl Saunders

Physics

The biaxial smectic-A* (Sm-AB*) phase, appearing in the phase sequence Sm-A*–Sm-AB*–Sm-C*, is analyzed using Landau theory. It is found to possess a helical superstructure with a pitch that is significantly shorter than the pitch of the Sm-C* helical superstructure. The Sm-AB*–Sm-C* transition can be either first or second order, and correspondingly there will be either a jump or continuous variation in the pitch. The behaviors of the birefringence and electroclinic effect are analyzed and found to be similar to those of a Sm-Cα …


Thermal-Initiated Hydroxyethyl Methacrylate Functionalization Of Multiwalled Carbon Nanotubes, Greg Curtzwiler, Philip Costanzo, Ray Fernando, Jeffrey E. Danes, Keith Vorst Jul 2011

Thermal-Initiated Hydroxyethyl Methacrylate Functionalization Of Multiwalled Carbon Nanotubes, Greg Curtzwiler, Philip Costanzo, Ray Fernando, Jeffrey E. Danes, Keith Vorst

Chemistry and Biochemistry

Multiwalled-carbon nanotubes (MWCNTs) were functionalized via thermoinitiated free radical polymerization of 2-hydroxyethyl methacrylate (HEMA) using benzoyl peroxide. Tip sonication was used during the polymerization reaction to separate agglomerated nanotubes. The functionalization was confirmed by control experiments and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR). Differential scanning calorimetry indicated that the addition of poly(HEMA)-MWCNTs to a two-component polyurethane coating will have little effect on the glass transition temperature of the coating. The poly(HEMA)-functionalized MWCNTs formed large colloidal structures of highly dispersed nanotubes in both the nonsheared and sheared coatings as determined by atomic force microscopy. This study determined a quick …


How To Combine Independent Data Sets For The Same Quantity, Theodore P. Hill, Jack Miller Jul 2011

How To Combine Independent Data Sets For The Same Quantity, Theodore P. Hill, Jack Miller

Research Scholars in Residence

This paper describes a new mathematical method called conflation for consolidating data from independent experiments that measure the same physical quantity. Conflation is easy to calculate and visualize and minimizes the maximum loss in Shannon information in consolidating several independent distributions into a single distribution. A formal mathematical treatment of conflation has recently been published. For the benefit of experimenters wishing to use this technique, in this paper we derive the principal basic properties of conflation in the special case of normally distributed (Gaussian) data. Examples of applications to measurements of the fundamental physical constants and in high energy physics …


Comparison Of A High Purity Germanium Gamma Ray Spectrometer And A Multidimensional Nai(T1) Scintillation Gamma Ray Spectrometer, Greg Stratton Jul 2011

Comparison Of A High Purity Germanium Gamma Ray Spectrometer And A Multidimensional Nai(T1) Scintillation Gamma Ray Spectrometer, Greg Stratton

Aerospace Engineering

This report compares two different gamma ray spectrometers in terms of performance, operation, and apparatus and also investigates the design and integration challenges of using gamma ray spectrometers in space. The first spectrometer is a one-dimensional high purity germanium (HPGe) spectrometer and the second is a multidimensional NaI(Tl) scintillation spectrometer (MGRS). The key results show that the HPGe exhibits 15 to 27 times better energy resolution than the MGRS, but the MGRS is 52 times more sensitive and removes 177 % more of the background radiation.


Generic Transient Memory Formation In Disordered Systems With Noise, Nathan C. Keim, Sidney R. Nagel Jul 2011

Generic Transient Memory Formation In Disordered Systems With Noise, Nathan C. Keim, Sidney R. Nagel

Physics

Out-of-equilibrium disordered systems may form memories of external driving in a remarkable fashion. The system ‘‘remembers’’ multiple values from a series of training inputs yet ‘‘forgets’’ nearly all of them at long times despite the inputs being continually repeated. Here, learning and forgetting are inseparable aspects of a single process. The memory loss may be prevented by the addition of noise. We identify a class of systems with this behavior, giving as an example a model of non-Brownian suspensions under cyclic shear.


Reducing Zero-Point Systematics In Dark Energy Supernova Experiments, L. Faccioli, A. G. Kim, R. Miquel, G. Bernstein, A. Bonissent, M. Brown, W. Carithers, Jodi L. Christiansen, N. Connolly, S. Deustua, D. Gerdes, L. Gladney, G. Kushner, E. V. Linder, S. Mckee, A. Mostek, H. Shukla, A. Stebbins, C. Stoughton, D. Tucker Jul 2011

Reducing Zero-Point Systematics In Dark Energy Supernova Experiments, L. Faccioli, A. G. Kim, R. Miquel, G. Bernstein, A. Bonissent, M. Brown, W. Carithers, Jodi L. Christiansen, N. Connolly, S. Deustua, D. Gerdes, L. Gladney, G. Kushner, E. V. Linder, S. Mckee, A. Mostek, H. Shukla, A. Stebbins, C. Stoughton, D. Tucker

Physics

We study the effect of filter zero-point uncertainties on future supernova dark energy missions. Fitting for calibration parameters using simultaneous analysis of all Type Ia supernova standard candles achieves a significant improvement over more traditional fit methods. This conclusion is robust under diverse experimental configurations (number of observed supernovae, maximum survey redshift, inclusion of additional systematics). This approach to supernova fitting considerably eases otherwise stringent mission calibration requirements. As an example we simulate a space-based mission based on the proposed JDEM satellite; however the method and conclusions are general and valid for any future supernova dark energy mission, ground or …


Using Forsee And Continuous Forest Inventory Information To Evaluate Implementation Of Uneven-Aged Management In Santa Cruz County Coast Redwood Forests, Douglas D. Piirto, Scott Sink, Dominic Ali, Steve Auten, Christopher Hipkin, Reid Cody Jun 2011

Using Forsee And Continuous Forest Inventory Information To Evaluate Implementation Of Uneven-Aged Management In Santa Cruz County Coast Redwood Forests, Douglas D. Piirto, Scott Sink, Dominic Ali, Steve Auten, Christopher Hipkin, Reid Cody

Natural Resources Management and Environmental Sciences

Swanton Pacific Ranch in northern Santa Cruz County has been owned and managed by California Polytechnic State University (Cal Poly) Foundation since 1987. The California Forest Practice Rules specific to Santa Cruz County limit harvest rate and opening size. Cal Poly forest managers are implementing uneven-aged forest management on 1,182 acres of 80 to 110 year old, second-growth coast redwood forests using a modified BDq approach. The Lockheed Fire spread into most of the managed forest area during the summer of 2009 causing significant mortality in lower diameter classes.