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2015

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Articles 11731 - 11760 of 12617

Full-Text Articles in Physical Sciences and Mathematics

Mapping Robinia Pseudoacacia Forest Health Conditions By Using Combined Spectral, Spatial, And Textural Information Extracted From Ikonos Imagery And Random Forest Classifier, Hong Wang, Yu Zhao, Ruiliang Pu Jan 2015

Mapping Robinia Pseudoacacia Forest Health Conditions By Using Combined Spectral, Spatial, And Textural Information Extracted From Ikonos Imagery And Random Forest Classifier, Hong Wang, Yu Zhao, Ruiliang Pu

School of Geosciences Faculty and Staff Publications

The textural and spatial information extracted from very high resolution (VHR) remote sensing imagery provides complementary information for applications in which the spectral information is not sufficient for identification of spectrally similar landscape features. In this study grey-level co-occurrence matrix (GLCM) textures and a local statistical analysis Getis statistic (Gi), computed from IKONOS multispectral (MS) imagery acquired from the Yellow River Delta in China, along with a random forest (RF) classifier, were used to discriminate Robina pseudoacacia tree health levels. Specifically, eight GLCM texture features (mean, variance, homogeneity, dissimilarity, contrast, entropy, angular second moment, and correlation) were first calculated from …

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Multi-Year Observations Of Breiðamerkurjökull, A Marine-Terminating Glacier In Southeastern Iceland, Using Terrestrial Radar Interferometry, Denis Voytenko, Timothy H. Dixon, Ian M. Howat, Noel Gourmelen, Chad Lembke, Charles L. Werner, Santiago De La Peña, Björn Oddsson Jan 2015

Multi-Year Observations Of Breiðamerkurjökull, A Marine-Terminating Glacier In Southeastern Iceland, Using Terrestrial Radar Interferometry, Denis Voytenko, Timothy H. Dixon, Ian M. Howat, Noel Gourmelen, Chad Lembke, Charles L. Werner, Santiago De La Peña, Björn Oddsson

School of Geosciences Faculty and Staff Publications

Terrestrial radar interferometry (TRI) is a new technique for studying ice motion and volume change of glaciers. TRI is especially useful for temporally and spatially dense measurements of highly dynamic glacial termini. We conducted a TRI survey of Breiðamerkurjökull, a marine-terminating glacier in Iceland, imaging its terminus near the end of the melt season in 2011, 2012 and 2013. The ice velocities were as high as 5 m d−1, with the fastest velocities near the calving front. Retreat of the glacier over the 3 year observation period was accompanied by strong embayment formation. Iceberg tracking with the radar shows high …

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Self-Reported Experiences Of Climate Change In Nigeria: The Role Of Personal And Socio-Environmental, Idowu Ajibade, Frederick Ato Armah, Vincent Kuuire, Isaac Luginaah, Gordon Mcbean Jan 2015

Self-Reported Experiences Of Climate Change In Nigeria: The Role Of Personal And Socio-Environmental, Idowu Ajibade, Frederick Ato Armah, Vincent Kuuire, Isaac Luginaah, Gordon Mcbean

Geography Faculty Publications and Presentations

In this study, we examined the individual and socio-environmental factors that mediate differential self-reported experiences of climate change in coastal communities in Lagos, Nigeria. Binary complementary log-log multivariate regression was used to model residents’ experiences of changing rainfall patterns, ocean surges, and flood events. An analysis of both compositional and contextual factors showed that there were urban communities where vulnerability to flooding tends to be clustered, and that this was not fully explained by the characteristics of the people of whom the community was composed. This study, thus, underscores the importance and complex nature of the interaction between personal and …

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Discourses Of Deflection: The Politics Of Framing China’S South North Water Transfer Project, Britt Crow-Miller Jan 2015

Discourses Of Deflection: The Politics Of Framing China’S South North Water Transfer Project, Britt Crow-Miller

Geography Faculty Publications and Presentations

Despite significant financial, ecological and social trade-offs, China has moved forward with constructing and operationalising the world’s largest interbasin water transfer project to date, the South-North Water Transfer Project (SNWTP). While it is fundamentally linked to broader political-economic goals within the context of China’s post-Mao development agenda, the SNWTP is frequently discussed in apolitical terms. Based on extensive discourse analysis and interviews with government officials across North China, I argue that the Chinese government is using "discourses of deflection" to present the project as politically neutral in order to serve its ultimate goal of maintaining the high economic growth rates …

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Multi-Instrumental Investigation Of Volcanic Outgassing At Pacaya Volcano, Guatemala., Carlo Prandi Jan 2015

Multi-Instrumental Investigation Of Volcanic Outgassing At Pacaya Volcano, Guatemala., Carlo Prandi

Dissertations, Master's Theses and Master's Reports

Pacaya is one of the most active volcano in the world and it is only ≈30Km South of Guatemala City, the capital of Guatemala, that has a population of about 2 million of people and a surrounding metropolitan area where ≈4.5 million of people live. So mitigate the volcanic hazard improving the knowledge and the understanding of Pacaya is fundamental to decrease the risk factor at which the surrounding population is exposed. This study aims to furnish a new large database, the analysis, the comparison and the interpretations of data that come from different techniques of sampling, about the volcanic …

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The Impact Of Different Cues On The Memorability Of System-Assigned Recognition-Based Textual Passwords, Kanis Fatema Jan 2015

The Impact Of Different Cues On The Memorability Of System-Assigned Recognition-Based Textual Passwords, Kanis Fatema

Computer Science and Engineering Theses

To ensure memorability, users employ predictable patterns when creating new passwords. These patterns make passwords easy to guess, which not only increases risks to users but also for the entire system. In contrast, system-assigned textual passwords offer security but suffer from poor memorability. Previous research investigated the idea of textual recognition, in which the user would be assigned a word from a list and asked to recall the word later. The recall rate for this scheme was shown to be no better than memorizing a sequence of randomly assigned letters, but the researchers suggested that memorability may be improved if …

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Biomedical Parameter Measurements Using Video Processing, Negar Ziaee Nasrabadi Jan 2015

Biomedical Parameter Measurements Using Video Processing, Negar Ziaee Nasrabadi

Computer Science and Engineering Theses

For quite some time, patients’ cardiovascular parameters have been measured by sensors connected to their body. One way of measuring these parameters is pulse oximetry by using an optical technique. It uses a photodetector to detect light absorption changes of red and infrared light. These two types of light serve as two sources of illumination. These current types of methods for monitoring parameters are often viewed as uncomfortable by the patient, and therefore are not desirable for frequent and long periods of monitoring. Furthermore, these methods can potentially produce a psychologically influenced bias from the patient because the patient is …

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Advanced Sparsity Techniques In Medical Imaging And Image Processing, Chen Chen Jan 2015

Advanced Sparsity Techniques In Medical Imaging And Image Processing, Chen Chen

Computer Science and Engineering Theses

In the past decades, sparsity techniques has been widely applied in the fields of medical imaging, computer vision, image processing, compressive sensing, machine learning etc., and gained great success. In this work, we propose new models of sparsity techniques, which is an extension to the standard sparsity used in the existing works and in the vein of structure sparsity families. First, we introduce the wavelet tree sparsity in natural images. It shows that the tree sparsity regularization often outperforms the existing standard sparsity based techniques in magnetic resonance imaging. Second, we extend the tree sparsity to forest sparsity on multi-channel …

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Gait Analysis On A Smart Floor For Health Monitoring, Oluwatosin Oluwadare Jan 2015

Gait Analysis On A Smart Floor For Health Monitoring, Oluwatosin Oluwadare

Computer Science and Engineering Theses

Gait analysis is the investigation of an individual pattern of walking. Based on studies in Psychophysics, it has been shown that the human gait contains unique information that is useful for the evaluation of foot and gait pathologies. The goal of this project is to use a floor mounted pressure sensor system capable of measuring a significant number of parameters relevant to gait to predict and detect anomalous behavior. The system consists of an array of pressure sensors mounted under floor tiles and computer hardware responsible for data collection. The method used in this project is unique since most systems …

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Design And Implementation Of An Open Beaconing Architecture For Internet Of Things, Arjun Kumar Bhaskar Shetty Jan 2015

Design And Implementation Of An Open Beaconing Architecture For Internet Of Things, Arjun Kumar Bhaskar Shetty

Computer Science and Engineering Theses

The power of the Internet is penetrating into the physical world with ever increasing speed and expanding reach under the general concept of Internet of Things. Extensive sets of efforts have been devoted toward establishing an interconnected network of smart devices in a self-organized manner. Nowadays, using low power beacons to announce the presences of physical objects has gained tremendous momentum exemplified by iBeacon from Apple. Unfortunately, schemes like iBeacon use abstract codes to denote a physical entity, limiting it to be only understandable by those with knowledge of it beforehand. In this thesis, we develop an open architecture where …

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Faster Sampling Over Theoritical And Online Social Networks, Ramakrishna Aduri Jan 2015

Faster Sampling Over Theoritical And Online Social Networks, Ramakrishna Aduri

Computer Science and Engineering Theses

Online social networks have become very popular recently and are used bymillions of users. Researchers increasingly want to leverage the rich variety ofinformation available. However, social networks often feature a web interface that onlyallows local-neighborhood queries - i.e., given a user of the online social network asinput, the system returns the immediate neighbors of the user. Additionally, they alsohave rate limits that restrict the number of queries issued over a given time period. Theserestrictions make third party analytics extremely challenging. The traditional approach ofusing random walks is not effective as they require significant burn-in period before theirstationary distribution converges to …

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Microblog Analyzer Aggregate Estimation Over A Micro Blog Platform, Satishkumar Masilamani Jan 2015

Microblog Analyzer Aggregate Estimation Over A Micro Blog Platform, Satishkumar Masilamani

Computer Science and Engineering Theses

Microblogging is a new mode of communication in which users can share their current status in brief and agile way in the form of text, image, video etc over smart phones, email or web. Recently, Microblogs such as Twitter, Tumblr, Google+ have experience phenomenal growth and are regularly used by millions of users. The data from microblogs is very useful for researchers to analyze various facets such as user behaviors, user intentions (like daily chatter, conversations, sharing information and reporting news), microblog social network structure etc. For example, a sociologist might want to use the microblog postings to analyze the …

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A Real-Time Embedded Data Acquisition System For Surface Measurements Using Multiple Line Lasers, A P Vikram Simha Jan 2015

A Real-Time Embedded Data Acquisition System For Surface Measurements Using Multiple Line Lasers, A P Vikram Simha

Computer Science and Engineering Theses

In the last few years there has been a significant increase in the number of hand held devices. These devices boast of delivering features such as high performance, low power consumption, high memory availability, serial and parallel interfacing capability, connectivity through the Ethernet, wireless, etc., at a very low cost. These embedded devices powered by open source software like Linux and Arduino have paved the way for the development of high efficiency, low cost portable products in a very short period of time.The objective of this thesis is to enhance the portability, efficiency, and other features of the existing Roline …

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Evaluating The Effectiveness Of Ben In Localizing Different Types Of Software Fault, Jaganmohan Chandrasekaran Jan 2015

Evaluating The Effectiveness Of Ben In Localizing Different Types Of Software Fault, Jaganmohan Chandrasekaran

Computer Science and Engineering Theses

Debugging refers to the activity of locating software faults in a program and is considered to be one of the most challenging tasks during software development. Automated fault localization tools have been developed to reduce the amount of effort and time software developers have to spend on debugging. In this thesis, we evaluate the effectiveness of a fault localization tool called BEN in locating different types of software faults. Assuming that combinatorial testing has been performed on the subject program, BEN leverages the result obtained from combinatorial testing to perform fault localization. Our evaluation focuses on how the following three …

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Performance Comparison Of Spatial Indexing Structures For Different Query Types, Neelabh Pant Jan 2015

Performance Comparison Of Spatial Indexing Structures For Different Query Types, Neelabh Pant

Computer Science and Engineering Theses

R-Trees are among the most popular multidimensional access methods suitable for indexing two dimensional spatial data and point data. R-Trees are found in most of the spatial database systems for indexing the spatial data. The data include points, lines and polygons which are retrieved and stored efficiently. There are many Spatial Database Systems which have incorporated R-Trees, for example, IBM Informix, Oracle Spatial, PostgreSQL and many others.Another version of R-Tree is R*-Tree which is also used for the same purpose i.e. indexing spatial data. R*-Tree has also been incorporated in an open source software SQLite with an extension of Spatialite. …

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Exploring 3d User Interface Technologies For Improving The Gaming Experience, Arun Kulshreshth Jan 2015

Exploring 3d User Interface Technologies For Improving The Gaming Experience, Arun Kulshreshth

Electronic Theses and Dissertations

3D user interface technologies have the potential to make games more immersive & engaging and thus potentially provide a better user experience to gamers. Although 3D user interface technologies are available for games, it is still unclear how their usage affects game play and if there are any user performance benefits. A systematic study of these technologies in game environments is required to understand how game play is affected and how we can optimize the usage in order to achieve better game play experience. This dissertation seeks to improve the gaming experience by exploring several 3DUI technologies. In this work, …

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True Linearized Intensity Modulation For Photonic Analog To Digital Conversion Using An Injection-Locked Mode-Locked Laser, Edris Sarailou Jan 2015

True Linearized Intensity Modulation For Photonic Analog To Digital Conversion Using An Injection-Locked Mode-Locked Laser, Edris Sarailou

Electronic Theses and Dissertations

A true linearized interferometric intensity modulator for pulsed light has been proposed and experimentally presented in this thesis. This has been achieved by introducing a mode-locked laser into one of the arms of a Mach-Zehnder interferometer and injection-locking it to the input light (which is pulsed and periodic). By modulating the injection-locked laser, and combining its output light with the light from the other arm of interferometer in quadrature, one can achieve true linearized intensity modulator. This linearity comes from the arcsine phase response of the injection-locked mode-locked laser (as suggested by steady-state solution of Adler's equation) when it is …

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Electronic Transport Properties Of Carbon Nanotubes: The Impact Of Atomic Charged Impurities, Ryuichi Tsuchikawa Jan 2015

Electronic Transport Properties Of Carbon Nanotubes: The Impact Of Atomic Charged Impurities, Ryuichi Tsuchikawa

Electronic Theses and Dissertations

Even changing one atom in nanoscale materials is expected to alter their properties due to their small physical sizes. Such sensitivity can be utilized to modify materials' properties from bottom up and is essential for the utility of nanoscale materials. As such, the impact of extrinsic atomic adsorbates was measured on pristine graphene and a network of carbon nanotubes using atomic hydrogen, cesium atoms, and dye molecules. In order to further quantify such an atomic influence, the resistance induced by a single potassium atom on metallic and semiconducting carbon nanotubes was measured for the first time. Carbon nanotubes are sensitive …

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Providing Context To The Clues: Recovery And Reliability Of Location Data From Android Devices, Connie Bell Jan 2015

Providing Context To The Clues: Recovery And Reliability Of Location Data From Android Devices, Connie Bell

Electronic Theses and Dissertations

Mobile device data continues to increase in significance in both civil and criminal investigations. Location data is often of particular interest. To date, research has established that the devices are location aware, incorporate a variety of resources to obtain location information, and cache the information in various ways. However, a review of the existing research suggests varying degrees of reliability of any such recovered location data. In an effort to clarify the issue, this project offers case studies of multiple Android mobile devices utilized in controlled conditions with known settings and applications in documented locations. The study uses data recovered …

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The Design, Implementation, And Refinement Of Wait-Free Algorithms And Containers, Steven Feldman Jan 2015

The Design, Implementation, And Refinement Of Wait-Free Algorithms And Containers, Steven Feldman

Electronic Theses and Dissertations

My research has been on the development of concurrent algorithms for shared memory systems that provide guarantees of progress. Research into such algorithms is important to developers implementing applications on mission critical and time sensitive systems. These guarantees of progress provide safety properties and freedom from many hazards, such as dead-lock, live-lock, and thread starvation. In addition to the safety concerns, the fine-grained synchronization used in implementing these algorithms promises to provide scalable performance in massively parallel systems. My research has resulted in the development of wait-free versions of the stack, hash map, ring buffer, vector, and a multi-word compare-and-swap …

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Vanadium Oxide Microbolometers With Patterned Gold Black Or Plasmonic Resonant Absorbers, Evan Smith Jan 2015

Vanadium Oxide Microbolometers With Patterned Gold Black Or Plasmonic Resonant Absorbers, Evan Smith

Electronic Theses and Dissertations

High sensitivity uncooled microbolometers are necessary to meet the needs of the next generation of infrared detectors, which seek low power consumption and production cost without sacrificing performance. Presented here is the design, fabrication, and characterization of a microbolometer with responsivity enhanced by novel highly absorptive coatings. The device utilizes a gold-doped vanadium oxide film in a standard air bridge design. Performance estimations are calculated from current theory, and efforts to maximize signal to noise ratio are shown and evaluated. Most notably, presented are the experimental results and analysis from the integration of two different absorptive coatings: a patterned gold …

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Density-Functional Theory+Dynamical Mean-Field Theory Study Of The Magnetic Properties Of Transition-Metal Nanostructures, Alamgir Kabir Jan 2015

Density-Functional Theory+Dynamical Mean-Field Theory Study Of The Magnetic Properties Of Transition-Metal Nanostructures, Alamgir Kabir

Electronic Theses and Dissertations

In this thesis, Density Functional Theory (DFT) and Dynamical Mean-Field Theory (DMFT) approaches are applied to study the magnetic properties of transition metal nanosystems of different sizes and compositions. In particular, in order to take into account dynamical electron correlation effects (time-resolved local charge interactions), we have adopted the DFT+DMFT formalism and made it suitable for application to nanostructures. Preliminary application of this DFT+DMFT approach, using available codes, to study the magnetic properties of small (2 to 5-atom) Fe and FePt clusters provide meaningful results: dynamical effects lead to a reduction of the cluster magnetic moment as compared to that …

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Photophysics Of Organic Probes And Their Applications In Bioimaging & Photodynamic Therapy, Bosung Kim Jan 2015

Photophysics Of Organic Probes And Their Applications In Bioimaging & Photodynamic Therapy, Bosung Kim

Electronic Theses and Dissertations

Over the past several decades the phenomenon of luminescence (divided into fluorescence and phosphorescence) has received great attention in the field of biological science. This quest has motivated scientists for a variety of applications, including fluorescence imaging. Fluorescence microscopy techniques that provide unique advantages, such as high spatial resolution and superior sensitivity, have been regarded as attractive tools in biophotonics. With the progress of ultrafast laser sources, two-photon absorption (2PA), in which a molecule absorbs two photons simultaneously, has opened possibilities of using it for various applications. Two-photon fluorescence microscopy (2PFM), which affords deeper tissue penetration and excellent three-dimensional (3D) …

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Transverse Mode Selection And Brightness Enhancement In Laser Resonators By Means Of Volume Bragg Gratings, Brian Anderson Jan 2015

Transverse Mode Selection And Brightness Enhancement In Laser Resonators By Means Of Volume Bragg Gratings, Brian Anderson

Electronic Theses and Dissertations

The design of high power lasers requires large mode areas to overcome various intensity driven nonlinear effects. Increasing the aperture size within the laser can overcome these effects, but typically result in multi-transverse mode output and reduced beam quality, limiting the brightness of the system. As one possible solution, the angular selectivity of a diffractive optical element is proposed as a spatial filter, allowing for the design of compact high brightness sources not possible with conventional methods of transverse mode selection. This thesis explores the angular selectivity of volume Bragg gratings (VBGs) and their use as spatial transverse mode filters …

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Gauging Training Effectiveness Of Virtual Environment Simulation Based Applications For An Infantry Soldier Training Task, Douglas Maxwell Jan 2015

Gauging Training Effectiveness Of Virtual Environment Simulation Based Applications For An Infantry Soldier Training Task, Douglas Maxwell

Electronic Theses and Dissertations

The U.S. Army Training and Doctrine Command*s Army Learning Concept 2015 and Army Training Concept 2025 are documents that discuss the need for an adaptive soldier learning model with a flexible training delivery methodology. The U.S. Army has been investing in serious gaming technology for the past two decades as a cost effective means to teach tactics and strategy. Today, the U.S. Army is seeking to expand its application of virtual environment training to areas such as cultural awareness and human network analysis for the infantry soldier. These new expanded applications will require a higher level of non-determinant behavior inside …

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Employees’ Social Networking Site Use Impact On Job Performance: Evidence From Pakistan, Murad Moqbel, Fizza Aftab Jan 2015

Employees’ Social Networking Site Use Impact On Job Performance: Evidence From Pakistan, Murad Moqbel, Fizza Aftab

Information Systems Faculty Publications and Presentations

This paper reinvestigates the impact of social networking site use by employees on job performance by conducting a methodological replication of Moqbel, Nevo, and Kock (2013) using samples (N=139) from Pakistan. In both studies, social networking site use has significant effects on organizational commitment and job satisfaction, and job satisfaction also has a significant impact on job performance and organizational commitment. In comparison with the U.S., we find that social networking site use in Pakistan has no significant impact on job performance through the mediating effect of job satisfaction, yet has a significant effect on organizational commitment and job satisfaction. …

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Crowdsourcing King Tide Flooding, Susan Jacobson, Juliet Pinto, Kate Macmillin, Tiffany Troxler-Gann Jan 2015

Crowdsourcing King Tide Flooding, Susan Jacobson, Juliet Pinto, Kate Macmillin, Tiffany Troxler-Gann

Sea Level Rise Collection

King Tides are the highest high tides in the year, usually peaking in the Spring and Fall. In South Florida, King Tides contribute to flooding along the coast and in other low-lying areas when the storm water system becomes overwhelmed with sea water. The water comes up through the sewer system, flooding streets and other areas. The tidal flood water can bring brackish water through storm drains inland.

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Engaging South Florida On Sea Level Rise: Eyes On The Rise, King Tides And Citizen Science, Juliet Pinto, Susan Jacobson Jan 2015

Engaging South Florida On Sea Level Rise: Eyes On The Rise, King Tides And Citizen Science, Juliet Pinto, Susan Jacobson

Sea Level Rise Collection

No abstract provided.

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A Freshwater Community On The Shawangunk Ridge In The Lower Mid-Hudson Valley, New York, Beryl Kahn, Howard R. Feldman, Leah Horowitz Jan 2015

A Freshwater Community On The Shawangunk Ridge In The Lower Mid-Hudson Valley, New York, Beryl Kahn, Howard R. Feldman, Leah Horowitz

Lander College for Women - The Anna Ruth and Mark Hasten School Publications and Research

The Shawangunk Ridge in the lower mid-Hudson Valley extends from the vicinity of Rosendale through New Jersey, Pennsylvania, Maryland and Virginia. Within the first thirty miles can be found five “sky lakes”: Mohonk, Minnewaska, Awosting, Mud Pond and Maratanza. Since these lakes occur on the top of the ridge they have no drainage basin. Here we report on the pH and other abiotic factors that impact the aquatic fauna of Mohonk Lake. The pH of the lake is 7 near the surface. Lake Minnewaska’s pH increased from 4 to 6 in the last twenty years. The pH of the other …

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Taxonomy, Paleobiogeography And Paleoecology Of Jurassic Ethiopian Brachipods: A Progress Report, Howard R. Feldman, Mark A. Wilson, Alexa J. Belowich Jan 2015

Taxonomy, Paleobiogeography And Paleoecology Of Jurassic Ethiopian Brachipods: A Progress Report, Howard R. Feldman, Mark A. Wilson, Alexa J. Belowich

Lander College for Women - The Anna Ruth and Mark Hasten School Publications and Research

The area under study belongs to the Jurassic Ethiopian Province (western North Africa, Egypt, Israel, Jordan, Saudi Arabia, Ethiopia, Eritrea, Kenya, Madagascar and Kachchh). Work was begun in 1978 in northern Sinai with the discovery of the large, rare Callovian brachiopod Septirhynchia hirschi and subsequent sampling of 6,000 feet of sediment at Gebel Maghara and Gebel Engabashi. In the Negev, southern Israel, we described a brachiopod fauna from the Matmor Formation that was deposited on a low energy, peritidal, shallow marine shelf. During the latter part of the Jurassic we recognize a connection with the pelagic western Neotethys. Some brachiopod …

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