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Clustering Data Of Mixed Categorical And Numerical Type With Unsupervised Feature Learning, Dao Lam, Mingzhen Wei, Donald C. Wunsch 2015 Missouri University of Science and Technology

Clustering Data Of Mixed Categorical And Numerical Type With Unsupervised Feature Learning, Dao Lam, Mingzhen Wei, Donald C. Wunsch

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Mixed-type categorical and numerical data are a challenge in many applications. This general area of mixed-type data is among the frontier areas, where computational intelligence approaches are often brittle compared with the capabilities of living creatures. In this paper, unsupervised feature learning (UFL) is applied to the mixed-type data to achieve a sparse representation, which makes it easier for clustering algorithms to separate the data. Unlike other UFL methods that work with homogeneous data, such as image and video data, the presented UFL works with the mixed-type data using fuzzy adaptive resonance theory (ART). UFL with fuzzy ART (UFLA) obtains …


Late Quaternary Speleogenesis And Landscape Evolution In A Tropical Carbonate Island: Pango La Kuumbi (Kuumbi Cave), Zanzibar, Nikos Kourampas, Ceri Shipton, William Mills, Ruth Tibesasa, Henrietta Horton, Mark Horton, Mary Prendergast, Alison Crowther, Katerina Douka, Patrick Faulkner, Llorenç Picornell, Nicole Boivin 2015 University of Stirling & University of Edinburgh

Late Quaternary Speleogenesis And Landscape Evolution In A Tropical Carbonate Island: Pango La Kuumbi (Kuumbi Cave), Zanzibar, Nikos Kourampas, Ceri Shipton, William Mills, Ruth Tibesasa, Henrietta Horton, Mark Horton, Mary Prendergast, Alison Crowther, Katerina Douka, Patrick Faulkner, Llorenç Picornell, Nicole Boivin

International Journal of Speleology

Kuumbi Cave is one of a group of caves that underlie a flight of marine terraces in Pleistocene limestone in eastern Zanzibar (Indian Ocean). Drawing on the findings of geoarchaeological field survey and archaeological excavation, we discuss the formation and evolution of Kuumbi Cave and its wider littoral landscape. In the later part of the Quaternary (last ca. 250,000 years?), speleogenesis and terrace formation were driven by the interplay between glacioeustatic sea level change and crustal uplift at rates of ca. 0.10-0.20 mm/yr. Two units of backreef/reef limestone were deposited during ‘optimal’ (highest) highstands, tentatively correlated with MIS 7 and …


An Investigation Into Transitions In Clay Mineral Chemistry On Mars, Seth Gainey 2015 University of Nevada, Las Vegas

An Investigation Into Transitions In Clay Mineral Chemistry On Mars, Seth Gainey

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation is comprised of three studies investigating clay mineralogy on, or near the martian surface, with an introductory chapter, introducing and linking the three studies. Chapter two is on the subject of clay mineral synthesis, including Fe/Mg clay minerals which have been detected at multiple locations across the southern highlands. These Fe/Mg clay minerals have been previously interpreted as forming in anoxic/reducing environments, conducive to the preservation of organic matter. The results of this study suggest that the previous interpretation of Fe/Mg-rich clay as requiring anoxic/reducing conditions may not be accurate, as the minor presence of Mg (below what …


The Science And Practice Of River Restoration, Ellen E. Wohl, Stuart N. Lane, Andrew C. Wilcox 2015 Colorado State University - Fort Collins

The Science And Practice Of River Restoration, Ellen E. Wohl, Stuart N. Lane, Andrew C. Wilcox

Geosciences Faculty Publications

River restoration is one of the most prominent areas of applied water-resources science. From an initial focus on enhancing fish habitat or river appearance, primarily through structural modification of channel form, restoration has expanded to incorporate a wide variety of management activities designed to enhance river process and form. Restoration is conducted on headwater streams, large lowland rivers, and entire river networks in urban, agricultural, and less intensively human-altered environments. We critically examine how contemporary practitioners approach river restoration and challenges for implementing restoration, which include clearly identified objectives, holistic understanding of rivers as ecosystems, and the role of restoration …


Shaw T. & Alenka ČUk, 2015. Slovene Karst And Caves In The Past, Arrigo A. Cigna 2015 UIS

Shaw T. & Alenka ČUk, 2015. Slovene Karst And Caves In The Past, Arrigo A. Cigna

International Journal of Speleology

No abstract provided.


Black Carbon Concentrations In Snow At Tronsen Meadow In Central Washington From 2012 To 2013: Temporal And Spatial Variations And The Role Of Local Forest Fire Activity, Ian Delaney, Susan D. Kaspari, Matthew Jenkins 2015 Central Washington University

Black Carbon Concentrations In Snow At Tronsen Meadow In Central Washington From 2012 To 2013: Temporal And Spatial Variations And The Role Of Local Forest Fire Activity, Ian Delaney, Susan D. Kaspari, Matthew Jenkins

Geological Sciences Faculty Scholarship

Characterizing black carbon (BC) concentrations in the seasonal snowpack is of interest because BC deposition on snow can reduce albedo and accelerate melt. In Washington State, USA snowmelt from the seasonal snowpack provides an important source of water resources, but minimal work has been done characterizing BC concentrations in snow in this region. BC concentrations in snow were monitored over two winters (2012 and 2013) at Tronsen Meadow, located near Blewett Pass in the eastern Cascade Mountains in Central Washington, to characterize spatial and temporal variations in BC concentrations, and the processes affecting BC concentrations in the snowpack. BC concentrations …


Dendrochronological Analysis Of The Mann Homestead, 2015 The College of Wooster

Dendrochronological Analysis Of The Mann Homestead

Historic Structures

Dating historical structures using dendrochronology. The Historical Structures collection consists of reports that are the result of dendochronological analysis of timbers from structures in Pennsylvania and Ohio. Contributors: Wiesenberg, Nicholas


Dendrochronological Analysis Of The Crowe Barn, 2015 The College of Wooster

Dendrochronological Analysis Of The Crowe Barn

Historic Structures

Dating historical structures using dendrochronology. The Historical Structures collection consists of reports that are the result of dendochronological analysis of timbers from structures in Pennsylvania and Ohio. Contributors: Wiesenberg, Nicholas


Glacier Change On The Three Sisters Volcanoes, Oregon: 1900-2010, Justin George Ohlschlager 2015 Portland State University

Glacier Change On The Three Sisters Volcanoes, Oregon: 1900-2010, Justin George Ohlschlager

Dissertations and Theses

A glacier responds to changes in climate by subsequent retreat and advance as a result of changes in snow inputs and outputs. Understanding these changes is important because shrinking glaciers limit and diminish local water resources. They contribute to alpine runoff in the late-summer months by delaying the maximum runoff until late in the melt season. A comprehensive glacier and perennial snowfield inventory has not been completed for the Three Sisters in Central Oregon. Using aerial photography, Digital Elevation Models (DEMs), previous studies, and historical ground based photographs these glacier and perennial snowfields were defined and their surface area change …


Using Data Visualization Software To Aid In The Analysis Of Geographical Data, Matthew R. Evers, Inzamam Rahaman 2015 Truman State University

Using Data Visualization Software To Aid In The Analysis Of Geographical Data, Matthew R. Evers, Inzamam Rahaman

STAR Program Research Presentations

NASA Web World Wind (Web WW) is designed to visualize and manage geographical data. As a first implementation of visualization and analysis, we designed an application to map earthquake data onto the globe. Portions of this code were merged with application monitoring magnetic field anomalies possibly associated with earthquake precursor activity. Web WW enabled the visualization of the directional vectors from this data to point to the source location of the earthquake. We also developed a prototype urban management application which utilizes OpenStreetMaps to provide simple features such as route navigation, geographical and services information in an area of interest. …


Identifying Glacial Movement Through Fluvial Sediment Analysis, Alexis D. Freeman 2015 California Polytechnic State University, San Luis Obispo

Identifying Glacial Movement Through Fluvial Sediment Analysis, Alexis D. Freeman

STAR Program Research Presentations

The primary purpose of this study is to better understand how climate affects river dynamics. It is also important to understand the relationship between glaciers and the transportation of sediments, as this allows us to study changes in transport through time. The studied sediments were gathered from outcrops located in Fresno Ca, off of Friant road. The origin of these sediments are the Sierra Nevada Mountains. Mesozoic metasedimentary and metavolcanic sediments are derived from the foothills, while the granitic sediments are derived from higher up in the mountains. The sediments are characterized by both their degree of rounding, and their …


Ua24 Mcicsl Newsletter - August 2015, Shannon R. Trimboli Education Coordinator 2015 Western Kentucky University

Ua24 Mcicsl Newsletter - August 2015, Shannon R. Trimboli Education Coordinator

MCICSL Newsletter

This issue includes the following:

Bat Night was a success for education and research

MCICSL participated in national network strategic planning

as well as Summer research opportunities


Geo-Needs Focus Group Meetings Report Executive Summary, Heather L. Petcovic, Sheldon P. Turner, Emily Geraghty Ward, Tina Cartwright, Nicole LaDue, David Mogk, Andrew P.K. Bentley, Xai Her 2015 Western Michigan University

Geo-Needs Focus Group Meetings Report Executive Summary, Heather L. Petcovic, Sheldon P. Turner, Emily Geraghty Ward, Tina Cartwright, Nicole Ladue, David Mogk, Andrew P.K. Bentley, Xai Her

Geological and Environmental Sciences Reports

Geo-Needs Stakeholder Needs Assessment for Broadening Participation in the Geoscience Workforce. Executive summary. The full meeting report is available at http://scholarworks.wmich.edu/geology_reports/1/


Geo-Needs: Stakeholder Needs Assessment For Broadening Participation In The Geoscience Workforce, Heather L. Petcovic, Sheldon P. Turner, Emily Geraghty Ward, Tina Cartwright, Nicole LaDue, David Mogk, Andrew P.K. Bentley, Xai Her 2015 Western Michigan University

Geo-Needs: Stakeholder Needs Assessment For Broadening Participation In The Geoscience Workforce, Heather L. Petcovic, Sheldon P. Turner, Emily Geraghty Ward, Tina Cartwright, Nicole Ladue, David Mogk, Andrew P.K. Bentley, Xai Her

Geological and Environmental Sciences Reports

Geo-Needs focus group meetings report from the August 5-7 and 9-11, 2015 conference at the Nothern Illinois University Conference Center in Naperville, Illinois.

Despite a significant investment of resources, underrepresented minorities constitute ~8% of the geoscience-related workforce, making the geosciences one of the least diverse of all science, technology, engineering, and math (STEM) disciplines. While this pattern of underrepresentation has been attributed to numerous factors, the Geo-Needs project is focused on lack of access to undergraduate courses and programs of study at two-year technical and community colleges (2YCs) and minority-serving institutions (MSIs). Based on our analysis, only about 2.5% of …


Seismic-Hazard Map Of Southeast Missouri And Likely Magnitude Of The February 1812 New Madrid Earthquake, Jaewon Chung, J. David Rogers 2015 Missouri University of Science and Technology

Seismic-Hazard Map Of Southeast Missouri And Likely Magnitude Of The February 1812 New Madrid Earthquake, Jaewon Chung, J. David Rogers

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The New Madrid seismic zone lies beneath the upper Mississippi Embayment, straddling the border between southeastern Missouri and northwestern Tennessee. In late 1811 and early 1812, it produced five earthquakes of magnitudes >6.5, violently shaking the central and eastern United States (CEUS). Its magnitude and recurrence are of concern to today's central United States regions. By considering the effects of local geology, deterministic scenario maps (Mw 7.3 and 7.7) were produced for ground motions intended to simulate the 7 February 1812 event (NM3), which was the largest felt. These maps include spatial estimates of peak ground acceleration and of …


Upper Plate Reverse Fault Reactivation And The Unclamping Of The Megathrust During The 2014 Northern Chile Earthquake Sequence, Gabriel González, Pablo Salazar, John P. Loveless, Richard W. Allmendinger, Felipe Aron, Mahesh Shrivastava 2015 Universidad Católica del Norte

Upper Plate Reverse Fault Reactivation And The Unclamping Of The Megathrust During The 2014 Northern Chile Earthquake Sequence, Gabriel González, Pablo Salazar, John P. Loveless, Richard W. Allmendinger, Felipe Aron, Mahesh Shrivastava

Geosciences: Faculty Publications

After 137 years without a great earthquake, the Mw 8.1 Pisagua event of 1 April 2014 occurred in the central portion of the southern Peru–northern Chile subduction zone. This megathrust earthquake was preceded by more than 2 weeks of foreshock activity migrating ∼3.5 km/day toward the mainshock hypocenter. This foreshock sequence was triggered by an Mw 6.7 earthquake on a reverse fault in the upper plate that strikes at a high angle to the trench, similar to well-documented reverse faults onshore. These margin-oblique reverse faults accommodate north-south shortening resulting from subduction across a plate boundary that is curved in map …


Geological Controls On Stratigraphy And Sedimentation Of The Mississippian Marshall Formation, Michigan Basin, U.S.A., Joseph G. Adducci 2015 Western Michigan University

Geological Controls On Stratigraphy And Sedimentation Of The Mississippian Marshall Formation, Michigan Basin, U.S.A., Joseph G. Adducci

Masters Theses

An understanding of regional orogenic, climatic, and eustatic processes is critical to the interbasinal correlation of Paleozoic strata in eastern North America. Tectonic activity associated with the culmination of Appalachian Orogenic events has been shown to have regional influence on paleostructure and sediment dispersal in the Appalachian foreland basin and adjacent intracratonic Illinois and Michigan basins. The culmination of the Acadian Orogeny at the end of the Devonian represents the beginning of a period of general tectonic quiescence extending throughout the early and middle Mississippian in eastern North America. Early Mississippian strata in the Michigan basin is distinctive and marks …


Deformation And Thermal Histories Of Ordinary Chondrites: Evidence For Postdeformation Annealing And Syn-Metamorphic Shock, Alexander M. Ruzicka, Richard Hugo, Melinda Hutson 2015 Portland State University

Deformation And Thermal Histories Of Ordinary Chondrites: Evidence For Postdeformation Annealing And Syn-Metamorphic Shock, Alexander M. Ruzicka, Richard Hugo, Melinda Hutson

Geology Faculty Publications and Presentations

We show that olivine microstructures in seven metamorphosed ordinary chondrites of different groups studied with optical and transmission electron microscopy can be used to evaluate the post-deformation cooling setting of the meteorites, and to discriminate between collisions affecting cold and warm parent bodies. The L6 chondrites Park (shock stage S1), Bruderheim (S4), Leedey (S4), and Morrow County (S5) were affected by variable shock deformation followed by relatively rapid cooling, and probably cooled as fragments liberated by impact in near-surface settings. In contrast, Kernouvé (H6 S1), Portales Valley (H6/7 S1), and MIL 99301 (LL6 S1) appear to have cooled slowly after …


Factors Affecting Terrigenous Sedimentation In Coastal Bays With Coral Reefs: Implications For Monitoring The Effectiveness Of Watershed Restoration, Whitney Sears 2015 University of San Diego

Factors Affecting Terrigenous Sedimentation In Coastal Bays With Coral Reefs: Implications For Monitoring The Effectiveness Of Watershed Restoration, Whitney Sears

Theses

In the Caribbean, sedimentation has been identified as a serious threat to coral reef communities. Although land-based sediment delivery to coastal waters harboring coral reefs occurs under natural conditions, human activities in the watersheds above reefs increases the erosion and delivery of terrigenous sediment to the reefs. Delivery of terrigenous sediment into marine areas below developed watersheds affects sedimentation rates, alters the composition and texture of sediments that are suspended in the water column, and/or sediments that are deposited on the sea floor and on corals.

St. John, U.S. Virgin Islands is an ideal location to study the effects of …


Biogeochemical Alteration Of Particulate Pyrogenic Organic Carbon (Pyc), Jason Matthew Stuart 2015 University of Southern Mississippi

Biogeochemical Alteration Of Particulate Pyrogenic Organic Carbon (Pyc), Jason Matthew Stuart

Master's Theses

The resistance of plant derived pyrogenic organic carbon (pyC) to abiotic and biotic means of degradation has led to increased interest in the role of pyC as a potential carbon sink, as well as a strategy for sequestering atmospheric CO2 to mitigate excess carbon emissions. Though much research pertaining to the fundamental properties of pyC degradation have been performed in a controlled lab setting, there has been very little work regarding pyC degradation in a field setting where factors such as precipitation and temperature fluctuate seasonally. This work focuses on various degradation characteristics of two …


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