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2007

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Articles 5221 - 5250 of 6758

Full-Text Articles in Physical Sciences and Mathematics

A Gui For The Deaf-Blind: An Additional Concepts Paper, David Veal Jan 2007

A Gui For The Deaf-Blind: An Additional Concepts Paper, David Veal

Research outputs pre 2011

People with some residual vision though still classified as blind may be able to read on screen patterns presented via a computer program whereby such a pattern can represent a textual character and a presentation of sequences of such patterns can represent words. These patterns can be adjusted to utilize the user’s remaining vision capacity. Previous research has shown that volunteers who where legally classified as blind could read simple sentences via such a system. This system is known as the Dynamic Pattern System (DPS) and is a test bed for research. Although this research involved a single pattern represented …


Triangulation Based Static Wide Angle Laser Scanning For Obstacle Detection, Kaveh Sahba, Kamal Alameh, Clifton Smith Jan 2007

Triangulation Based Static Wide Angle Laser Scanning For Obstacle Detection, Kaveh Sahba, Kamal Alameh, Clifton Smith

Research outputs pre 2011

This paper demonstrates discrete laser spot projection over a wide angle using a novel cylindrical quasi-cavity waveguide, with no moving parts. Furthermore, the distance to each spot is calculated using active laser triangulation. The triangulation arrangement and the trajectory of principal rays are modelled using a system of linear equations based on optical geometry. Linear algebra is used to derive the unique baseline and outgoing angle of every projected beam. The system is calibrated by finding optimal values for uncertain instrumental parameters using constrained non-linear optimization. Distances calculated indoors result in accuracies of over 93%


Design And Characterization Of Cmos/Soi Image Sensors, Igor Brouk, Kamal Alameh, Yael Nemirovsky Jan 2007

Design And Characterization Of Cmos/Soi Image Sensors, Igor Brouk, Kamal Alameh, Yael Nemirovsky

Research outputs pre 2011

The design, operation, and characterization of CMOS imagers implemented using: 1) "regular" CMOS wafers with a 0.5-mum CMOS analog process; 2) "regular" CMOS wafers with a 0.35-mum CMOS analog process; and 3) silicon-on-insulator (SOI) wafers in conjunction with a 0.35-mum CMOS analog process, are discussed in this paper. The performances of the studied imagers are compared in terms of quantum efficiency, dark current, and optical bandwidth. It is found that there is strong dependence of quantum efficiency of the photodiodes on the architecture of the image sensor. The results of this paper are useful for designing and modeling CMOS/SOI image …


Wavelength-Encoded Ocdma System Using Opto-Vlsi Processors, Muhsen Aljada, Kamal Alameh Jan 2007

Wavelength-Encoded Ocdma System Using Opto-Vlsi Processors, Muhsen Aljada, Kamal Alameh

Research outputs pre 2011

We propose and experimentally demonstrate a 2.5 Gbits/sper user wavelength-encoded optical code-division multiple-access encoder-decoder structure based on opto-VLSI processing. Each encoder and decoder is constructed using a single 1D opto-very-large-scale-integrated (VLSI) processor in conjunction with a fiber Bragg grating (FBG) array of different Bragg wavelengths. The FBG array spectrally and temporally slices the broadband input pulse into several components and the opto-VLSI processor generates codewords using digital phase holograms. System performance is measured in terms of the autocorrelation and cross-correlation functions as well as the eye diagram.


Use Of A Continuous Wave Raman Fiber Laser In Graded-Index Multimode Fiber For Srs Beam Combination, Nathan B. Terry, Kevin T. Engel, Thomas G. Alley, Timothy H. Russell Jan 2007

Use Of A Continuous Wave Raman Fiber Laser In Graded-Index Multimode Fiber For Srs Beam Combination, Nathan B. Terry, Kevin T. Engel, Thomas G. Alley, Timothy H. Russell

Faculty Publications

We report using a Raman fiber laser (RFL) based on a multimode graded-index fiber as a novel method for beam combination of two continuous wave pump beams. Due to stimulated Raman scattering, the RFL generates a Stokes beam which can be up to 300% brighter than the pump beams. Up to 5.8 W of Stokes power is generated with an optical conversion efficiency of 56%.


Magnetic Enhancement In Cobalt-Manganese Alloy Clusters, Shuangye Yin, Ramiro Moro, Xiaoshan Xu, Walter A. De Heer Jan 2007

Magnetic Enhancement In Cobalt-Manganese Alloy Clusters, Shuangye Yin, Ramiro Moro, Xiaoshan Xu, Walter A. De Heer

Xiaoshan Xu Papers

Magnetic moments of CoNMnM and CoNVM clusters (N ≤ 60; M ≤ N/3) are measured in molecular beams using the Stern-Gerlach deflection method. Surprisingly, the per atom average moments of CoNMnM clusters are found to increase with Mn concentration, in contrast to bulk CoMn. The enhancement with Mn doping is found to be independent of cluster size and composition in the size range studied. Meanwhile, CoNVM clusters show reduction of average moments with increasing V doping, consistent with what is expected in bulk CoV. The results are …


Geology, Geography, And Humans Battle For Dominance Over The Delivery Of Fluvial Sediment To The Coastal Ocean, James P.M. Syvitski, John D. Milliman Jan 2007

Geology, Geography, And Humans Battle For Dominance Over The Delivery Of Fluvial Sediment To The Coastal Ocean, James P.M. Syvitski, John D. Milliman

VIMS Articles

Sediment flux to the coastal zone is conditioned by geomorphic and tectonic influences (basin area and relief), geography (temperature, runoff), geology (lithology, ice cover), and human activities (reservoir trapping, soil erosion). A new model, termed “BQART” in recognition of those factors, accounts for these varied influences. When applied to a database of 488 rivers, the BQART model showed no ensemble over‐ or underprediction, had a bias of just 3% across six orders of magnitude in observational values, and accounted for 96% of the between‐river variation in the long‐term (±30 years) sediment load or yield of these rivers. The geographical range …


Multiphoton Response Of Retinal Rod Photoreceptors, Vasilios Alexiades, Harihar Khanal Jan 2007

Multiphoton Response Of Retinal Rod Photoreceptors, Vasilios Alexiades, Harihar Khanal

Publications

Phototransduction is the process by which light is converted into an electrical response in retinal photoreceptors. Rod photoreceptors contain a stack of (about 1000) disc membranes packed with photopigment rhodopsin molecules, which absorb the photons. We present computational experiments which show the profound effect on the response of the distances (how many discs apart) photons happen to be absorbed at. This photon-distribution effect alone can account for much of the observed variability in response.


Significant Suppression Of Ferromagnetism By Hydrostatic Pressure In The Diluted Magnetic Semiconductor Sb2−Xvxte3 With Xï0.03, Jeffrey Dyck, T J. Mitchell, A J. Luciana, P. C. Quayle, Č. DrašAr, P. LošT’ÁK Jan 2007

Significant Suppression Of Ferromagnetism By Hydrostatic Pressure In The Diluted Magnetic Semiconductor Sb2−Xvxte3 With Xï0.03, Jeffrey Dyck, T J. Mitchell, A J. Luciana, P. C. Quayle, Č. DrašAr, P. LošT’ÁK

Physics

No abstract provided.


Positive Solutions Of A Nonlinear Higher Order Boundary-Value Problem, John R. Graef, Johnny Henderson, Bo Yang Jan 2007

Positive Solutions Of A Nonlinear Higher Order Boundary-Value Problem, John R. Graef, Johnny Henderson, Bo Yang

Faculty Articles

The authors consider the higher order boundary-value problem u (n)(t) = q(t)f(u(t)), 0 ≤ t ≤ 1, u(i-1)(0) = u (n-2)(p) = u(n-1)(1) = 0, 1 ≤ i ≤ n -2, where n ≥ 4 is an integer, and p ∈ (1/2, 1) is a constant. Sufficient conditions for the existence and nonexistence of positive solutions of this problem are obtained. The main results are illustrated with an example.


Estimates Of Positive Solutions To A Boundary Value Problem For The Beam Equation, Bo Yang Jan 2007

Estimates Of Positive Solutions To A Boundary Value Problem For The Beam Equation, Bo Yang

Faculty Articles

We consider a two-point boundary value problem for the fourth order beam equation. New upper and lower estimates of positive solutions of the problem are obtained.


Predicting Crime Reporting With Decision Trees And The National Crime Victimization Survey, Gondy Leroy, Juliette Gutierrez '13 Jan 2007

Predicting Crime Reporting With Decision Trees And The National Crime Victimization Survey, Gondy Leroy, Juliette Gutierrez '13

CGU Faculty Publications and Research

Crime reports are used by law enforcement to find criminals, prevent further violations, identify problems causing crimes and allocate government resources. Unfortunately, many crimes go unreported. This may lead to an incorrect crime picture and suboptimal responses to the existing situation. Our goal is to use a data mining approach to increase understanding of when crime is reported or not. An increased understanding could lead to new, more effective programs to fight crime or changes to existing programs. We use the National Crime Victimization Survey (NCVS) which comprises data collected from 45,000 households about incidents, victims, suspects and if the …


Natural Language Processing And E-Government: Extracting Reusable Crime Report Information, Gondy A. Leroy, Alicia Iriberri '06 Jan 2007

Natural Language Processing And E-Government: Extracting Reusable Crime Report Information, Gondy A. Leroy, Alicia Iriberri '06

CGU Faculty Publications and Research

Crime reporting needs to be possible 24/7. Although 911 and tip-lines are the most publicized reporting mechanisms, several other options exist, ranging from in-person reporting to online submissions. Internet-based crime reporting systems allow victims and witnesses of crime to report incidents to police 24/7 from any location. However, these existing e-mail and text-based systems provide little support for witnesses' memory recall leading to reports with less information and lower accuracy. These systems also do not facilitate reuse and integration of the reported information with other information systems. We are developing an anonymous Online Crime Reporting System that is designed to …


A Classifier To Evaluate Language Specificity In Medical Documents, Trudi Miller '08, Gondy A. Leroy, Samir Chatterjee, Jie Fan, Brian Thoms '09 Jan 2007

A Classifier To Evaluate Language Specificity In Medical Documents, Trudi Miller '08, Gondy A. Leroy, Samir Chatterjee, Jie Fan, Brian Thoms '09

CGU Faculty Publications and Research

Consumer health information written by health care professionals is often inaccessible to the consumers it is written for. Traditional readability formulas examine syntactic features like sentence length and number of syllables, ignoring the target audience's grasp of the words themselves. The use of specialized vocabulary disrupts the understanding of patients with low reading skills, causing a decrease in comprehension. A naive Bayes classifier for three levels of increasing medical terminology specificity (consumer/patient, novice health learner, medical professional) was created with a lexicon generated from a representative medical corpus. Ninety-six percent accuracy in classification was attained. The classifier was then applied …


Revealing The Antecedents And Benefits Of Kms Use: An Exploratory Study In A Petroleum Company In Oman, Kamla Al-Busaidi '05, Lorne Olfman, Terry Ryan, Gondy Leroy Jan 2007

Revealing The Antecedents And Benefits Of Kms Use: An Exploratory Study In A Petroleum Company In Oman, Kamla Al-Busaidi '05, Lorne Olfman, Terry Ryan, Gondy Leroy

CGU Faculty Publications and Research

This pilot study aimed to explore technical and social antecedents and benefits of KMS use in a petroleum company in Oman. Data was collected through questionnaire given to KMS users. From the technical perspective, results uncovered that both knowledge utilizers and contributors were concerned about the system ease of use, speed and integration. Knowledge utilizers also valued knowledge richness in terms of relevancy and timeliness. From the social perspective, both knowledge utilizers and contributors considered time/availability as the major determinant of their behaviors. The results also suggested that knowledge utillizers valued the technical factors more than the social factors, whereas, …


Reducing Non-Target Hazards Of Rodenticides In Forest Settings, Wendy M. Arjo, David T. Bryson Jan 2007

Reducing Non-Target Hazards Of Rodenticides In Forest Settings, Wendy M. Arjo, David T. Bryson

United States Department of Agriculture Wildlife Services: Staff Publications

Mammalian damage to forest resources is widespread and causes annual economic loss. Wildlife damage control is very important to the intensified land use practices and the economics of reforestation using seedlings. Reforestation areas provide ideal habitat for many wildlife species. However, animals negatively impact trees more severely during stand establishment than at any other time. While numerous non-lethal and lethal tools are available for large and medium-sized mammals, fewer tools are available for small mammals. The damage caused by these rodent species has in some cases warranted the use of rodenticides to control populations. Rodenticides are effective tools for reducing …


Lectures In Computational Fluid Dynamics Of Incompressible Flow: Mathematics, Algorithms And Implementations, James M. Mcdonough Jan 2007

Lectures In Computational Fluid Dynamics Of Incompressible Flow: Mathematics, Algorithms And Implementations, James M. Mcdonough

Mechanical Engineering Textbook Gallery

From Prologue:

The present lecture notes are written to emphasize the mathematics of the Navier–Stokes (N.–S.) equations of incompressible flow and the algorithms that have been developed over the past 30 years for solving them.


Generalized Geologic Map For Land-Use Planning: Barren County, Kentucky, Daniel I. Carey, Joshua J. Johnson Jan 2007

Generalized Geologic Map For Land-Use Planning: Barren County, Kentucky, Daniel I. Carey, Joshua J. Johnson

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Generalized Geologic Map For Land-Use Planning: Washington County, Kentucky, Daniel I. Carey Jan 2007

Generalized Geologic Map For Land-Use Planning: Washington County, Kentucky, Daniel I. Carey

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Generalized Geologic Map For Land-Use Planning: Perry County, Kentucky, Bart Davidson, Steven E. Webb, Daniel I. Carey Jan 2007

Generalized Geologic Map For Land-Use Planning: Perry County, Kentucky, Bart Davidson, Steven E. Webb, Daniel I. Carey

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Generalized Geologic Map For Land-Use Planning: Leslie County, Kentucky, Daniel I. Carey, Steven E. Webb, Bart Davidson Jan 2007

Generalized Geologic Map For Land-Use Planning: Leslie County, Kentucky, Daniel I. Carey, Steven E. Webb, Bart Davidson

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Generalized Geologic Map For Land-Use Planning: Lawrence County, Kentucky, Daniel I. Carey Jan 2007

Generalized Geologic Map For Land-Use Planning: Lawrence County, Kentucky, Daniel I. Carey

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Generalized Geologic Map For Land-Use Planning: Harlan County, Kentucky, Daniel I. Carey, Steven E. Webb, Bart Davidson Jan 2007

Generalized Geologic Map For Land-Use Planning: Harlan County, Kentucky, Daniel I. Carey, Steven E. Webb, Bart Davidson

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Generalized Geologic Map For Land-Use Planning: Letcher County, Kentucky, Daniel I. Carey, Steven E. Webb, Bart Davidson Jan 2007

Generalized Geologic Map For Land-Use Planning: Letcher County, Kentucky, Daniel I. Carey, Steven E. Webb, Bart Davidson

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Generalized Geologic Map For Land-Use Planning: Rockcastle County, Kentucky, Daniel I. Carey Jan 2007

Generalized Geologic Map For Land-Use Planning: Rockcastle County, Kentucky, Daniel I. Carey

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Relations Among Algebraic Models Of 1-Connected Homotopy 3-Types, Erdal Ulualan Jan 2007

Relations Among Algebraic Models Of 1-Connected Homotopy 3-Types, Erdal Ulualan

Turkish Journal of Mathematics

In this paper, we explore the relations among reduced cases of algebraic models for homotopy 3-types for groups such as braided crossed and quadratic modules and reduced simplicial groups with Moore complex of length 2.


An Example Of An Indecomposable Module Without Non-Zero Hollow Factor Modules, Christian Lomp Jan 2007

An Example Of An Indecomposable Module Without Non-Zero Hollow Factor Modules, Christian Lomp

Turkish Journal of Mathematics

A module M is called hollow-lifting if every submodule N of M such that M/N is hollow contains a direct summand D \subseteq N such that N/D is a small submodule of M/D. A module M is called lifting if such a direct summand D exists for every submodule N. We construct an indecomposable module M without non-zero hollow factor modules, showing that there are hollow-lifting modules which are not lifting. The existences of such modules had been left open in a recent work by N. Orhan, D. Keskin-Tütüncü and R. Tribak [2].


Racial Inequality In The Distribution Of Hazardous Waste: A National-Level Reassessment, Paul Mohai, Robin Saha Jan 2007

Racial Inequality In The Distribution Of Hazardous Waste: A National-Level Reassessment, Paul Mohai, Robin Saha

Environmental Studies Faculty Publications

National-level studies examining racial disparities around hazardous waste treatment, storage, and disposal facilities have been very influential in defining the academic and political debates about the existence and importance of "environmental injustice." However, these studies tend to employ methods that fail to adequately control for proximity between environmentally hazardous sites and nearby residential populations. By using GIS and applying methods increasingly used in environmental inequality research that better control for proximity, we conduct a comprehensive reassessment of racial inequality in the distribution of the nation 's hazardous waste facilities. We compare the magnitude of racial disparities found with those of …


The Itsaq Gneiss Complex Of Southern West Greeland And The Construction Of Eoarchaean Crust At Convergent Plate Boundaries, Allen P. Nutman, Clark R. L Friend, Kenji Horie, Hiroshi Hidaka Jan 2007

The Itsaq Gneiss Complex Of Southern West Greeland And The Construction Of Eoarchaean Crust At Convergent Plate Boundaries, Allen P. Nutman, Clark R. L Friend, Kenji Horie, Hiroshi Hidaka

Faculty of Science - Papers (Archive)

The ca. 3000 km2ItsaqGneissComplex of the Nuuk region, southernWestGreenland was the first body of pre-3600 Ma crust discovered. Such ancient gneisses are now also known elsewhere, but in total form only about a millionth of the modern crust. The other 99.9999% of ancient crust was destroyed by melting and erosion over billions of years. Understanding the origin of this oldest crust is hampered by metamorphism (repeatedly) in the amphibolite or granulite facies, and most of it having been strongly deformed. The ItsaqGneissComplex is dominated by polyphase grey gneisses derived from several suites of tonalites, granites and subordinate quartz-diorites and ferro-gabbros …


~3,850 Ma Tonalites In The Nuuk Region, Greenland: Geochemistry And Their Reworking Within An Eoarchaean Gneiss Complex, Allen P. Nutman, Vickie C. Bennett, Clark R. L Friend, Kenji Horie, Hiroshi Hidaka Jan 2007

~3,850 Ma Tonalites In The Nuuk Region, Greenland: Geochemistry And Their Reworking Within An Eoarchaean Gneiss Complex, Allen P. Nutman, Vickie C. Bennett, Clark R. L Friend, Kenji Horie, Hiroshi Hidaka

Faculty of Science - Papers (Archive)

The Eoarchaean (>3,600 Ma) Itsaq Gneiss Complex of southern West Greenland is dominated by polyphase orthogneisses with a complex Archaean tectonothermal history. Some of the orthogneisses have c. 3,850 Ma zircons, and they vary from rare single phase metatonalites to more common complexly banded migmatites. This is due to heterogeneous strain, in situ anatexis and granitic veining superimposed during younger tectonothermal events. In the single-phase tonalites with c. 3,850 Ma zircon, oscillatory-zoned prismatic zircon is all 3,850 Ma old, but shows patchy ancient loss of radiogenic Pb. SHRIMP spot analyses and laser ablation ICP-MS depth profiling show that thin …