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2013

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Articles 1 - 30 of 11128

Full-Text Articles in Physical Sciences and Mathematics

Workshop | Body Worn Video Recorders: The Socio-Technical Implications Of Gathering Direct Evidence, Katina Michael, Alexander Hayes Jun 2015

Workshop | Body Worn Video Recorders: The Socio-Technical Implications Of Gathering Direct Evidence, Katina Michael, Alexander Hayes

Alexander Hayes Mr.

- From in-car video recording to body-worn video recording

- Exploring available technologies: how do they work, pros and cons

- Storing direct evidence in secure storage: factors to consider

- Citizens “shooting” back with POV tech – what are their rights?

- Crowdsourced sousveillance- harnessing public data for forensic profiling

- Police force policies and practices on the application of new media


Crater Detection Via Genetic Search Methods To Reduce Image Features, Joseph Paul Cohen Dec 2013

Crater Detection Via Genetic Search Methods To Reduce Image Features, Joseph Paul Cohen

Graduate Masters Theses

Recent approaches to crater detection have been inspired by face detection's use of gray-scale texture features. Using gray-scale texture features for supervised machine learning crater detection algorithms provides better classification of craters in planetary images than previous methods. When using Haar features it is typical to generate thousands of numerical values from each candidate crater image. This magnitude of image features to extract and consider can spell disaster when the application is an entire planetary surface. One solution is to reduce the number of features extracted and considered in order to increase accuracy as well as speed. Feature subset ...


A Model For The Hysteresis Observed In Gating Of Lysenin Channels, Eric Krueger, Radwan Al Faouri, Daniel Fologea, Ralph Henry, David Straub, Greg J. Salamo Dec 2013

A Model For The Hysteresis Observed In Gating Of Lysenin Channels, Eric Krueger, Radwan Al Faouri, Daniel Fologea, Ralph Henry, David Straub, Greg J. Salamo

Physics Faculty Publications and Presentations

The pore-forming toxin lysenin self-inserts to form conductance channels in natural and artificial lipid membranes containing sphingomyelin. The inserted channels exhibit voltage regulation and hysteresis of the macroscopic current during the application of positive periodic voltage stimuli. We explored the bi-stable behavior of lysenin channels and present a theoretical approach for the mechanism of the hysteresis to explain its static and dynamic components. This investigation develops a model to incorporate the role of charge accumulation on the bilayer lipid membrane in influencing the channel conduction state. Our model is supported by experimental results and also provides insight into the temperature ...


Studying Soil Moisture And Land-To-Water Carbon Export In Urbanized Coastal Areas Using Remotely Sensed Data And A Regional Hydro-Ecological Model, Yun Yang Dec 2013

Studying Soil Moisture And Land-To-Water Carbon Export In Urbanized Coastal Areas Using Remotely Sensed Data And A Regional Hydro-Ecological Model, Yun Yang

Graduate Doctoral Dissertations

The main objective of this research was to study the flux of dissolved organic carbon (DOC) from a terrestrial urbanized watershed to an estuarine system using a process-based regional hydro-ecological model and remotely sensed data.

While DOC is an important component of the global carbon cycle, the link of the variations in terrestrial carbon storage is still poorly understood. Soil moisture is a key factor that influences the amount of available water for vegetation growth and the decomposition rate of organic matter in the soil and thus contributes to the amount of DOC in the soil at the land-water boundary ...


Front Matter Dec 2013

Front Matter

Journal of Digital Forensics, Security and Law

No abstract provided.


Exponentiated Kumaraswamy-Dagum Distribution With Applications To Income And Lifetime Data, Shujiao Huang, Broderick O. Oluyede Dec 2013

Exponentiated Kumaraswamy-Dagum Distribution With Applications To Income And Lifetime Data, Shujiao Huang, Broderick O. Oluyede

Mathematical Sciences Faculty Publications

A new family of distributions called exponentiated Kumaraswamy-Dagum (EKD) distribution is proposed and studied. This family includes several well known sub-models, such as Dagum (D), Burr III (BIII), Fisk or Log-logistic (F or LLog), and new sub-models, namely, Kumaraswamy-Dagum (KD), Kumaraswamy-Burr III (KBIII), Kumaraswamy-Fisk or Kumaraswamy-Log-logistic (KF or KLLog), exponentiated Kumaraswamy-Burr III (EKBIII), and exponentiated Kumaraswamy-Fisk or exponentiated Kumaraswamy-Log-logistic (EKF or EKLLog) distributions. Statistical properties including series representation of the probability density function, hazard and reverse hazard functions, moments, mean and median deviations, reliability, Bonferroni and Lorenz curves, as well as entropy measures for this class of distributions and the ...


Back Matter Dec 2013

Back Matter

Journal of Digital Forensics, Security and Law

No abstract provided.


U.S. Drought Monitor, December 31, 2013, Matthew Rosencrans Dec 2013

U.S. Drought Monitor, December 31, 2013, Matthew Rosencrans

US Ag in Drought Archive

Drought map of U.S. for December 31, 2013 (12/31/13) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.


Impacts Of U.S. Biofuels Mandates On Environmental And Energy Security, Mohammad Alshawaf Dec 2013

Impacts Of U.S. Biofuels Mandates On Environmental And Energy Security, Mohammad Alshawaf

Graduate Doctoral Dissertations

Congress passed the Energy Policy Act of 2005 and the Energy Independence and Security Act (EISA) of 2007 to reduce dependency on foreign oil by increasing the use of biofuels. EISA mandates 36 billion gallons of biofuel production in 2022, representing an increase of 118% in eight years. Existing and new farmland are expected to be employed to produce corn and other feedstock necessary to fulfill the biofuel mandate. There is little research on the potential environmental impact on water resources of meeting the ESIA biofuel mandates.

The objectives of this EISA study were twofold. First, the study measured the ...


Evolution Of Magnetism In The Single-Crystal Honeycomb Iridates (Na1−XLiX)2Iro3, Gang Cao, Tongfei Qi, L. Li, Jsaminka Terzic, Vincent Shian Cao, Shujuan Yuan, M. Tovar, Ganpathy Murthy, Ribhu K. Kaul Dec 2013

Evolution Of Magnetism In The Single-Crystal Honeycomb Iridates (Na1−XLiX)2Iro3, Gang Cao, Tongfei Qi, L. Li, Jsaminka Terzic, Vincent Shian Cao, Shujuan Yuan, M. Tovar, Ganpathy Murthy, Ribhu K. Kaul

Physics and Astronomy Faculty Publications

We report the successful synthesis of single crystals of the layered iridate (Na1−xLix)2IrO3, 0 ≤ x ≤ 0.9, and a thorough study of its structural, magnetic, thermal, and transport properties. This compound allows a controlled interpolation between Na2IrO3 and Li2IrO3, while maintaining the quantum magnetism of the honeycomb Ir4+ planes. The measured phase diagram demonstrates a suppression of the Néel temperature TN at an intermediate x, indicating that the magnetic orders in Na2IrO3 and Li2IrO3 are distinct. X-ray data show ...


Masthead Dec 2013

Masthead

Journal of Digital Forensics, Security and Law

No abstract provided.


Planar Anchoring Strength And Pitch Measurements In Achiral And Chiral Chromonic Liquid Crystals Using 90-Degree Twist Cells, Christine K. Mcginn , '16, Laura I. Laderman , '15, N. Zimmermann, H.-S. Kitzerow, Peter J. Collings Dec 2013

Planar Anchoring Strength And Pitch Measurements In Achiral And Chiral Chromonic Liquid Crystals Using 90-Degree Twist Cells, Christine K. Mcginn , '16, Laura I. Laderman , '15, N. Zimmermann, H.-S. Kitzerow, Peter J. Collings

Physics & Astronomy Faculty Works

Chromonic liquid crystals are formed by molecules that spontaneously assemble into anisotropic structures in water. The ordering unit is therefore a molecular assembly instead of a molecule as in thermotropic liquid crystals. Although it has been known for a long time that certain dyes, drugs, and nucleic acids form chromonic liquid crystals, only recently has enough knowledge been gained on how to control their alignment so that studies of their fundamental liquid crystal properties can be performed. In this article, a simple method for producing planar alignment of the nematic phase in chromonic liquid crystals is described, and this in ...


Local Rings Of Embedding Codepth At Most 3 Have Only Trivial Semidualizing Complexes, Saeed Nasseh, Sean Sather-Wagstaff Dec 2013

Local Rings Of Embedding Codepth At Most 3 Have Only Trivial Semidualizing Complexes, Saeed Nasseh, Sean Sather-Wagstaff

Mathematical Sciences Faculty Publications

We prove that a local ring R of embedding codepth at most 3 has at most two semidualizing complexes up to shift-isomorphism, namely, R itself and a dualizing R-complex if one exists.


Healthcare Worker Contact Networks And The Prevention Of Hospital-Acquired Infections, Donald E. Curtis, Christopher S. Hlady, Gaurav Kanade, Sriram V. Pemmaraju, Philip M. Polgreen, Alberto M. Segre Dec 2013

Healthcare Worker Contact Networks And The Prevention Of Hospital-Acquired Infections, Donald E. Curtis, Christopher S. Hlady, Gaurav Kanade, Sriram V. Pemmaraju, Philip M. Polgreen, Alberto M. Segre

Department of Computer Science Publications

We present a comprehensive approach to using electronic medical records (EMR) for constructing contact networks of healthcare workers in a hospital. This approach is applied at the University of Iowa Hospitals and Clinics (UIHC) – a 3.2 million square foot facility with 700 beds and about 8,000 healthcare workers – by obtaining 19.8 million EMR data points, spread over more than 21 months. We use these data to construct 9,000 different healthcare worker contact networks, which serve as proxies for patterns of actual healthcare worker contacts. Unlike earlier approaches, our methods are based on large-scale data and do ...


Three X-Ray Transients In M31 Oberserved With Swift, R. Voss, W. Pietsch, F. Haberl, H. Stiele, J. Greiner, G. Sala, Dieter H. Hartmann, D. Hatzidimitriou Dec 2013

Three X-Ray Transients In M31 Oberserved With Swift, R. Voss, W. Pietsch, F. Haberl, H. Stiele, J. Greiner, G. Sala, Dieter H. Hartmann, D. Hatzidimitriou

Publications

Aims.The purpose of this study is to find transient X-ray sources in M 31, and to investigate and classify their nature.Methods.Three X-ray transients were observed with Swift. For each of the three X-ray transients we use the Swift X-ray and opticaldata together with observations from XMM-Newton and Chandra to investigate the lightcurves and the spectra of the outburst, andthereby to identify the source types. Results.The outburst of XMMU J004215.8+ 411924 lasted for about one month. The source had a hard power-law spectrum with aphoton index of 1.6. It was previously identified as a Be ...


Nicotine Exploits A Copi-Mediated Process For Chaperone-Mediated Up-Regulation Of Its Receptors, Brandon J. Henderson, Rahul Srinivasan, Weston A. Nichols, Crystal N. Dilworth, Diana F. Gutierrez, Elisha D. W. Mackey, Sheri Mckinney, Ryan M. Drenan, Christopher I. Richards, Henry A. Lester Dec 2013

Nicotine Exploits A Copi-Mediated Process For Chaperone-Mediated Up-Regulation Of Its Receptors, Brandon J. Henderson, Rahul Srinivasan, Weston A. Nichols, Crystal N. Dilworth, Diana F. Gutierrez, Elisha D. W. Mackey, Sheri Mckinney, Ryan M. Drenan, Christopher I. Richards, Henry A. Lester

Chemistry Faculty Publications

Chronic exposure to nicotine up-regulates high sensitivity nicotinic acetylcholine receptors (nAChRs) in the brain. This up-regulation partially underlies addiction and may also contribute to protection against Parkinson's disease. nAChRs containing the α6 subunit (α6* nAChRs) are expressed in neurons in several brain regions, but comparatively little is known about the effect of chronic nicotine on these nAChRs. We report here that nicotine up-regulates α6* nAChRs in several mouse brain regions (substantia nigra pars compacta, ventral tegmental area, medial habenula, and superior colliculus) and in neuroblastoma 2a cells. We present evidence that a coat protein complex I (COPI)-mediated process ...


Frameworks With Crystallographic Symmetry, Ciprian Borcea, Ileana Streinu Dec 2013

Frameworks With Crystallographic Symmetry, Ciprian Borcea, Ileana Streinu

Computer Science: Faculty Publications

Periodic frameworks with crystallographic symmetry are investigated from the perspective of a general deformation theory of periodic bar-and-joint structures in Rd. It is shown that natural parametrizations provide affine section descriptions for families of frameworks with a specified graph and symmetry. A simple geometric setting for diaplacive phase transitions is obtained. Upper bounds are derived for the number of realizations of minimally rigid periodic graphs.


On The Orientation Dependence Of The Casimir Force, Christopher David Markle Dec 2013

On The Orientation Dependence Of The Casimir Force, Christopher David Markle

All Theses and Dissertations (ETDs)

In the 83 years of its development, Casimir force theory has seen many advances.

However, there still exists a need for more comprehensive approaches, particularly to complex geometries. To this end we have developed an approach to the Casimir force and demonstrated its use in predicting the Casimir force present in many cases such as the case of a single hollow sphere, finite size parallel plates, and anisotropic conductors.

Within the field of Casimir force experimentation, many predicted characteristics have not yet been demonstrated. To that end, we are performing an experiment designed to investigate the orientational dependence of the ...


Wavelength Correction Of Refractivity Variation Measurements, Lee R. Burchett, Steven T. Fiorino Dec 2013

Wavelength Correction Of Refractivity Variation Measurements, Lee R. Burchett, Steven T. Fiorino

Faculty Publications

The index of refraction structure constant,C2n indicates how strongly the index of refraction varies in a region of the atmosphere. These variations usually arise through turbulent motions, creating an inhomogeneous distribution of species, density, temperature and pressure. Because the index of refraction also depends on wavelength, the measured value of C2n will depend on wavelength. This C2n difference generally becomes more pronounced as the difference in wavelength increases. This paper describes a technique for converting between measurements of C2n at different wavelengths, and gives an example for converting from centimeter to ...


Volatization Of Extraterrestrial Materials As Determined By Zinc Isotopic Analysis, Randal Christopher Paniello Dec 2013

Volatization Of Extraterrestrial Materials As Determined By Zinc Isotopic Analysis, Randal Christopher Paniello

All Theses and Dissertations (ETDs)

None


Primary Care-Based Educational Interventions To Decrease Risk Factors For Metabolic Syndrome For Adults With Major Psychotic And/Or Affective Disorders: A Systematic Review, Cynthia Nover, Sarah S. Jackson Dec 2013

Primary Care-Based Educational Interventions To Decrease Risk Factors For Metabolic Syndrome For Adults With Major Psychotic And/Or Affective Disorders: A Systematic Review, Cynthia Nover, Sarah S. Jackson

Epidemiology Faculty Publications

Background

Individuals with major psychotic and/or affective disorders are at increased risk for developing metabolic syndrome due to lifestyle- and treatment-related factors. Numerous pharmacological and non-pharmacological interventions have been tested in inpatient and outpatient mental health settings to decrease these risk factors. This review focuses on primary care-based non-pharmacological (educational or behavioral) interventions to decrease metabolic syndrome risk factors in adults with major psychotic and/or affective disorders.

Methods

The authors conducted database searches of PsychINFO, MEDLINE and the Cochrane Database of Systematic Reviews, as well as manual searches and gray literature searches to identify included studies.

Results

The ...


Timing And Spectroscopy Requirements For A Plastic Scintillating Fiber Bundle Time-Of-Flight Neutron Spectrometer, Paul A. Clement Dec 2013

Timing And Spectroscopy Requirements For A Plastic Scintillating Fiber Bundle Time-Of-Flight Neutron Spectrometer, Paul A. Clement

Theses and Dissertations

The design parameters of a Time-of-Flight (TOF) neutron spectrometer composed of BCF-12 plastic scintillating fibers were investigated. A GEANT4 transport model was developed for analyzing the interaction of 2.5 MeV neutrons with a 14 x 14 BCF-12 fiber bundle. The bundle simulation demonstrated that 0.359% of all neutrons incident on the bundle will double scatter. The timing and data collection e efficiencies of a Tektronix DPO7104 series digital oscilloscope were examined to determine the signal processing requirements for future fiber bundle measurements. The minimum detectable neutron energy was computed by taking into account the bundle scintillation e efficiency ...


Understanding Human Learning Using A Multiagent Based Unified Learning Model Simulation, Vlad T. Chiriacescu Dec 2013

Understanding Human Learning Using A Multiagent Based Unified Learning Model Simulation, Vlad T. Chiriacescu

Computer Science and Engineering: Theses, Dissertations, and Student Research

Within cognitive science, computational modeling based on cognitive architectures has been an important approach to addressing questions of human cognition and learning. Modeling issues such as limited expressivity in representing knowledge and lack of appropriate selection of model structure represent a challenge for existing architectures. Furthermore, latest research shows that the concepts of long-term memory, motivation and working memory are critical cognitive aspects but a unifying cognitive paradigm integrating those concepts hasn’t been previously achieved.

Derived from a synthesis of neuroscience, cognitive science, psychology, and education, the Unified Learning Model (ULM) provides this integration by merging a statistical learning ...


Optimal Allocation Of Distributed Reactive Power Resources Under Network Constraints For System Loss Minimization, L Meegahapola, S Abbott, D Morrow, T Littler, D Flynn Dec 2013

Optimal Allocation Of Distributed Reactive Power Resources Under Network Constraints For System Loss Minimization, L Meegahapola, S Abbott, D Morrow, T Littler, D Flynn

Dr Lasantha G Meegahapola

Abstract-Reactive power control is an important control issue for distribution system operators due to increased penetration of distributed generation. The work presented in this paper utilizes the inherent reactive power capability of the doubly-fed induction generator (DFIG) based wind farms to optimize the system losses while considering the network constraints in the system. The IEEE-30 bus system was modified by installing DFIG based wind farms in the medium voltage (MV) region creating three wind clusters in the network. The steady-state analysis was conducted to illustrate the loss minimization capability of the DFIG based wind farms under different reactive power configurations ...


Frequency Dynamics During High Ccgt And Wind Penetrations, Lasantha Meegahapola, Damian Flynn Dec 2013

Frequency Dynamics During High Ccgt And Wind Penetrations, Lasantha Meegahapola, Damian Flynn

Dr Lasantha G Meegahapola

Frequency stability is the paramount concern for secure and reliable operation of a power system. High wind penetration levels are reported in power systems with high thermal generation, and hence its likely to result high wind and combined-cycle gas turbine (CCGT) penetrations during system operation since CCGTs are the most preferable choice for the thermal generation. The doubly-fed induction generators (DFIGs) do not provide any inertial response while the CCGTs have unique frequency response during the system frequency disturbances. Therefore, CCGT turbine response characteristics and the zero inertial response may influence on frequency dynamics of a power network. The main ...


Coordinated Utilisation Of Wind Farm Reactive Power Capability For System Loss Optimisation, Lasantha Meegahapola, S Durairaj, D Flynn, B Fox Dec 2013

Coordinated Utilisation Of Wind Farm Reactive Power Capability For System Loss Optimisation, Lasantha Meegahapola, S Durairaj, D Flynn, B Fox

Dr Lasantha G Meegahapola

Most wind farms currently being installed are based upon doubly fed induction generator (DFIG) or direct-drive synchronous generator (DDSG) technology. Given that one of the impacts of introducing distributed generation is an alteration of steady-state power flows and voltages, both technologies are capable of providing local voltage support. Wind farms may, therefore, be included in optimal power flow (OPF) calculations to minimise fuel cost and/or network losses. The IEEE 30-bus system is considered as a case study, comparing fixed-speed induction generator (FSIG) requirements with DFIG capability. Results are presented for a range of DFIG capability modes, at varying system ...


Rfid-Based Anti-Theft Auto Security System With An Immobilizer, Geeth Jayendra, Sisil Kumarawadu, Lasantha Meegahapola Dec 2013

Rfid-Based Anti-Theft Auto Security System With An Immobilizer, Geeth Jayendra, Sisil Kumarawadu, Lasantha Meegahapola

Dr Lasantha G Meegahapola

This paper presents a novel radio frequency identification (RFID) based vehicle immobilizer system, which features low hacking probability while preserving the safety of the passengers of the hijacked vehicle. The immobilizer uses the active RFID technology where the tag is generated with comparatively large character sets. The receiving unit is intelligently integrated into three control circuits in the vehicle, namely, ignition circuit, power control unit, and automatic gear changing system, enabling it to bring the vehicle speed down to zero in a safe step by step manner. The anti-theft auto security system proposed here was tested under different weather conditions ...


A Genetic Algorithm Based Approach To Lv Radial Distribution Feeders Load Reconfiguration, Geeth Jayendra, Sisil Kumarawadu, Lasantha Meegahapola Dec 2013

A Genetic Algorithm Based Approach To Lv Radial Distribution Feeders Load Reconfiguration, Geeth Jayendra, Sisil Kumarawadu, Lasantha Meegahapola

Dr Lasantha G Meegahapola

No abstract provided.


Spectroscopic And Physico-Chemical Characterization Of Ir(I) And Ru(Iii) Complexes Of 32-Membered Unsymmetrical Dinucleating Macrocyclic Ligand, Mohammad Mansoob Khan Dr Dec 2013

Spectroscopic And Physico-Chemical Characterization Of Ir(I) And Ru(Iii) Complexes Of 32-Membered Unsymmetrical Dinucleating Macrocyclic Ligand, Mohammad Mansoob Khan Dr

Dr. Mohammad Mansoob Khan

No abstract provided.


Spectral Redemption In Clustering Sparse Networks, Florent Krzakala, Cristopher Moore, Elchanan Mossel, Joe Neeman, Allan Sly, Lenka Zdeborová, Pan Zhang Dec 2013

Spectral Redemption In Clustering Sparse Networks, Florent Krzakala, Cristopher Moore, Elchanan Mossel, Joe Neeman, Allan Sly, Lenka Zdeborová, Pan Zhang

Statistics Papers

Spectral algorithms are classic approaches to clustering and community detection in networks. However, for sparse networks the standard versions of these algorithms are suboptimal, in some cases completely failing to detect communities even when other algorithms such as belief propagation can do so. Here, we present a class of spectral algorithms based on a nonbacktracking walk on the directed edges of the graph. The spectrum of this operator is much better-behaved than that of the adjacency matrix or other commonly used matrices, maintaining a strong separation between the bulk eigenvalues and the eigenvalues relevant to community structure even in the ...