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Full-Text Articles in Physical Sciences and Mathematics

Scalable Approaches For Supporting Mpi-Io Atomicity, Peter Aarestad, George K. Thiruvathukal, Avery Ching, Alok Choudhary Nov 2011

Scalable Approaches For Supporting Mpi-Io Atomicity, Peter Aarestad, George K. Thiruvathukal, Avery Ching, Alok Choudhary

George K. Thiruvathukal

Scalable atomic and parallel access to noncontiguous regions of a file is essential to exploit high performance I/O as required by large-scale applications. Parallel I/O frameworks such as MPI I/O conceptually allow I/O to be defined on regions of a file using derived datatypes. Access to regions of a file can be automatically computed on a perprocessor basis using the datatype, resulting in a list of (offset, length) pairs. We describe three approaches for implementing lock serving (whole file, region locking, and byterange locking) and compare the various approaches using three noncontiguous I/O benchmarks. We present the details of the …


Scalable Implementations Of Mpi Atomicity For Concurrent Overlapping I/O, Wei-Keng Liao, Alok Choudhary, Kenin Coloma, George K. Thiruvathukal, Lee Ward, Eric Russell, Neil Pundit Nov 2011

Scalable Implementations Of Mpi Atomicity For Concurrent Overlapping I/O, Wei-Keng Liao, Alok Choudhary, Kenin Coloma, George K. Thiruvathukal, Lee Ward, Eric Russell, Neil Pundit

George K. Thiruvathukal

For concurrent I/O operations, atomicity defines the results in the overlapping file regions simultaneously read/written by requesting processes. Atomicity has been well studied at the file system level, such as POSIX standard. In this paper, we investigate the problems arising from the implementation of MPI atomicity for concurrent overlapping write access and provide a few programming solutions. Since the MPI definition of atomicity differs from the POSIX one, an implementation that simply relies on the POSIX file systems does not guarantee correct MPI semantics. To have a correct implementation of atomic I/O in MPI, we examine the efficiency of three …


Natural Xml For Data Binding, Processing, And Persistence, George K. Thiruvathukal, Konstantin Läufer Nov 2011

Natural Xml For Data Binding, Processing, And Persistence, George K. Thiruvathukal, Konstantin Läufer

George K. Thiruvathukal

The article explains what you need to do to incorporate XML directly into your computational science application. The exploration involves the use of a standard parser to automatically build object trees entirely from application-specific classes. This discussion very much focuses on object-oriented programming languages such as Java and Python, but it can work for non-object-oriented languages as well. The ideas in the article provide a glimpse into the Natural XML research project.


Restfs: Resources And Services Are Filesystems, Too, Joseph P. Kaylor, Konstantin Läufer, George K. Thiruvathukal Nov 2011

Restfs: Resources And Services Are Filesystems, Too, Joseph P. Kaylor, Konstantin Läufer, George K. Thiruvathukal

George K. Thiruvathukal

We have designed and implemented RestFS, a software frame-work that provides a uniform, configurable connector layerfor mapping remote web-based resources to local filesystem-based resources, recognizing the similarity between thesetwo types of resources. Such mappings enable programmaticaccess to a resource, as well as composition of two or moreresources, through the local operating system’s standardfilesystem application programming interface (API), script-able file-based command-line utilities, and inter-process com-munication (IPC) mechanisms. The framework supports au-tomatic and manual authentication. We include several ex-amples intended to show the utility and practicality of ourframework.


City Of Hampton, Virginia Shoreline Inventory Report Methods And Guidelines, Marcia Berman, Harry Berquist, Sharon Killeen, Carl Hershner, Karinna Nunez, Karen Reay, Tamia Rudnicky Nov 2011

City Of Hampton, Virginia Shoreline Inventory Report Methods And Guidelines, Marcia Berman, Harry Berquist, Sharon Killeen, Carl Hershner, Karinna Nunez, Karen Reay, Tamia Rudnicky

Reports

The data inventory developed for the Shoreline Inventory is based on a three‑tiered shoreline assessment approach. In most cases this assessment characterizes conditions that can be observed from a small boat navigating along the shoreline. The three tiered shoreline assessment approach divides the shorezone into three regions: 1) the immediate riparian zone, evaluated for land use; 2) the bank, evaluated for height, stability, cover and natural protection; and 3) the shoreline, describing the presence of shoreline structures for shore protection and recreational purposes. Hand-held GPS units are used to log features observed in the field.

Three GIS coverages are developed …


Summary Tables: Northampton County, Virginia Shoreline Inventory Report, Marcia Berman, Harry Berquist, Sharon Killeen, Carl Hershner, Karinna Nunez, Karen Reay, Tamia Rudnicky, Daniel E. Schatt Nov 2011

Summary Tables: Northampton County, Virginia Shoreline Inventory Report, Marcia Berman, Harry Berquist, Sharon Killeen, Carl Hershner, Karinna Nunez, Karen Reay, Tamia Rudnicky, Daniel E. Schatt

Reports

The Shoreline Inventory Summary Tables quantify observed conditions based on river systems, such as the combined length of linear features (e.g. shoreline miles surveyed, miles of bulkhead and revetment), the total number of point features (e.g. docks, boathouses, boat ramps) & total acres of polygon features (tidal marshes).


Analyzing Black Cloud Dynamics Over Cairo, Nile Delta Region And Alexandria Using Aerosols And Water Vapor Data, Hesham El-Askary, Anup K. Prasad, George Kallos, Mohamed El Raey, Menas Kafatos Jul 2011

Analyzing Black Cloud Dynamics Over Cairo, Nile Delta Region And Alexandria Using Aerosols And Water Vapor Data, Hesham El-Askary, Anup K. Prasad, George Kallos, Mohamed El Raey, Menas Kafatos

Biology, Chemistry, and Environmental Sciences Faculty Books and Book Chapters

Cairo is the largest city of Africa and one of the world’s megacities, with a population of more than 20 million people and containing more than one third of the national industry. It is a rapidly expanding city which leads to many associated environmental problems. As a result, it is also one of the most air polluted megacities in the world (Molina and Molina, 2004). It suffers from high ambient concentrations of atmospheric pollutants including particulates (PM), carbon monoxide, nitrogen oxides, ozone and sulfur dioxide (Abu-Allaban et al., 2007, Abu-Allaban et al., 2002, El-Metwally et …


Pedagogical Tool For Usability Science Final Project Report, Daniel D. Mendelsohn Jun 2011

Pedagogical Tool For Usability Science Final Project Report, Daniel D. Mendelsohn

Honors Theses

A Sophomore Research Seminar (SRS) at Union College teaches about usability science, the study of designing interfaces that allow the user to accomplish a given task with less time and frustration. In this context, an interface can be anything that allows interaction with a physical or virtual device such as a web browser or the knobs on a stove. In this SRS, students design interface mockups, called prototypes, out of inexpensive material such as cardboard. Students use these prototypes to test their interfaces on real people, who are asked to perform a task that would be performed on a real …


R-Process Nucleosynthesis In Supernova Simulation, Lyda P. Urresta Jun 2011

R-Process Nucleosynthesis In Supernova Simulation, Lyda P. Urresta

Honors Theses

We examined a potential r-process site by modeling nucleosynthesis in a late-stage supernova explosion, considering different hydrodynamic conditions. After collecting the resultant abundances with respect to atomic and mass number, we decayed the isotopes in our data sample to stability. Then, we plotted the decayed and undecayed abundances with respect to their atomic number and mass number, and compared them to the abundances procured from solar and metal-poor halo star data. Both of these environments are known to house r-process elements, and an agreement between the observed abundance data and the abundance data from our simulation would support the theory …


A Statistical Method To Correct Radiometric Data Measured By Avhrr Onboard The National Oceanic And Atmospheric Administration (Noaa) Polar Orbiting Environmental Satellites (Poes), Md Zahidur Rahman, Leonid Roytman, Abdelhamid Kadik May 2011

A Statistical Method To Correct Radiometric Data Measured By Avhrr Onboard The National Oceanic And Atmospheric Administration (Noaa) Polar Orbiting Environmental Satellites (Poes), Md Zahidur Rahman, Leonid Roytman, Abdelhamid Kadik

Publications and Research

This paper apply an statistical technique to correct radiometric data measured by Advanced Very High Resolution Radiometers(AVHRR) onboard the National Oceanic and Atmospheric Administration (NOAA) Polar Orbiting Environmental Satellites(POES). This paper study Normalized Difference Vegetation Index (NDVI) stability in the NOAA/NESDIS Global Vegetation Index (GVI) data for the period 1982-2003. AVHRR weekly data for the five NOAA afternoon satellites NOAA-7, NOAA-9, NOAA-11, NOAA-14, and NOAA-16 are used for the China dataset, for it includes a wide variety or different ecosystems represented globally. GVI has found wide use for studying and monitoring land surface, atmosphere, and recently for analyzing climate and …


Restfs: Resources And Services Are Filesystems, Too, Joseph P. Kaylor, Konstantin Läufer, George K. Thiruvathukal Mar 2011

Restfs: Resources And Services Are Filesystems, Too, Joseph P. Kaylor, Konstantin Läufer, George K. Thiruvathukal

Computer Science: Faculty Publications and Other Works

We have designed and implemented RestFS, a software frame-work that provides a uniform, configurable connector layerfor mapping remote web-based resources to local filesystem-based resources, recognizing the similarity between thesetwo types of resources. Such mappings enable programmaticaccess to a resource, as well as composition of two or moreresources, through the local operating system’s standardfilesystem application programming interface (API), script-able file-based command-line utilities, and inter-process com-munication (IPC) mechanisms. The framework supports au-tomatic and manual authentication. We include several ex-amples intended to show the utility and practicality of ourframework.


2011 Chesapeake Bay Bridge Tunnel Station Tide Prediction Calendars, Virginia Institute Of Marine Science, David A. Evans Jan 2011

2011 Chesapeake Bay Bridge Tunnel Station Tide Prediction Calendars, Virginia Institute Of Marine Science, David A. Evans

Miscellaneous

These calendars are produced monthly using David Evans' Tidecal.


2011 Wachapreague Station Tide Prediction Calendars, Virginia Institute Of Marine Science, David A. Evans Jan 2011

2011 Wachapreague Station Tide Prediction Calendars, Virginia Institute Of Marine Science, David A. Evans

Miscellaneous

These calendars are produced monthly using David Evans' Tidecal.


2011 Hampton Roads Station Tide Prediction Calendars, Virginia Institute Of Marine Science, David A. Evans Jan 2011

2011 Hampton Roads Station Tide Prediction Calendars, Virginia Institute Of Marine Science, David A. Evans

Miscellaneous

These calendars are produced monthly using David Evans' Tidecal.


2011 Gloucester Point Station Tide Prediction Calendars, Virginia Institute Of Marine Science, David A. Evans Jan 2011

2011 Gloucester Point Station Tide Prediction Calendars, Virginia Institute Of Marine Science, David A. Evans

Miscellaneous

These calendars are produced monthly using David Evans' Tidecal.


Gis Data: Northampton County, Virginia Shoreline Inventory Report, Marcia Berman, Harry Berquist, Sharon Killeen, Carl Hershner, Karinna Nunez, Karen Reay, Tamia Rudnicky, Daniel E. Schatt Jan 2011

Gis Data: Northampton County, Virginia Shoreline Inventory Report, Marcia Berman, Harry Berquist, Sharon Killeen, Carl Hershner, Karinna Nunez, Karen Reay, Tamia Rudnicky, Daniel E. Schatt

Data

The data inventory developed for the Shoreline Inventory is based on a three tiered shoreline assessment approach. In most cases this assessment characterizes conditions that can be observed from a small boat navigating along the shoreline. The three tiered shoreline assessment approach divides the shorezone into three regions:

1 ) the immediate riparian zone, evaluated for land use; 2 ) the bank, evaluated for height, stability, cover and natural protection; and 3 ) the shoreline, describing the presence of shoreline structures for shore protection and recreational purposes. Hand-held GPS units are used to log features observed in the field.

Three …


Power Line Enhancement For Data Monitoring Of Neural Electrical Activity In The Human Body, Ahmed M. Haidar, Sridhathan C, Abdulsalam Hazza, Ahmed Saleh Jan 2011

Power Line Enhancement For Data Monitoring Of Neural Electrical Activity In The Human Body, Ahmed M. Haidar, Sridhathan C, Abdulsalam Hazza, Ahmed Saleh

Faculty of Informatics - Papers (Archive)

Distance and real-time data monitoring are the necessary condition that makes any system in good working order. Recent advancements in micro-electronics and wireless technology enable the application of wireless sensors in both industry and wild environments. However, Long-distance wireless communication has several drawbacks like limited bandwidth, considerable costs and unstable connection quality. Therefore, Power Line Communication (PLC) using pre-established Power Lines (PL) becomes more attractive for high data transmission technology. This paper reviews the existing distance data monitoring systems and presents a case study for data transferring of temperature and heart beat measurement. The simulations were carried out on the …


Methane Observations From The Greenhouse Gases Observing Satellite: Comparison To Ground-Based Tccon Data And Model Calculations, Robert Parker, Hartmut Boesch, Austin Cogan, Annemarie Fraser, Liang Feng, Paul Palmer, Janina Messerschmidt, Nicholas M. Deutscher, David W. Griffith, Justus Notholt, Paul O. Wennberg, Debra Wunch Jan 2011

Methane Observations From The Greenhouse Gases Observing Satellite: Comparison To Ground-Based Tccon Data And Model Calculations, Robert Parker, Hartmut Boesch, Austin Cogan, Annemarie Fraser, Liang Feng, Paul Palmer, Janina Messerschmidt, Nicholas M. Deutscher, David W. Griffith, Justus Notholt, Paul O. Wennberg, Debra Wunch

Faculty of Science - Papers (Archive)

We report new short-wave infrared (SWIR) column retrievals of atmospheric methane (X CH4) from the Japanese Greenhouse Gases Observing SATellite (GOSAT) and compare observed spatial and temporal variations with correlative ground-based measurements from the Total Carbon Column Observing Network (TCCON) and with the global 3-D GEOS-Chem chemistry transport model. GOSAT X CH4 retrievals are compared with daily TCCON observations at six sites between April 2009 and July 2010 (Bialystok, Park Falls, Lamont, Orleans, Darwin and Wollongong). GOSAT reproduces the site-dependent seasonal cycles as observed by TCCON with correlations typically between 0.5 and 0.7 with an estimated single-sounding precision between 0.4-0.8%. …


Rocky Intertidal Temperature Variability Along The Southeast Coast Of Australia: Comparing Data From In Situ Loggers, Satellite-Derived Sst And Terrestrial Weather Stations, Justin Adam Lathlean, David J. Ayre Prof, Todd E. Minchinton Jan 2011

Rocky Intertidal Temperature Variability Along The Southeast Coast Of Australia: Comparing Data From In Situ Loggers, Satellite-Derived Sst And Terrestrial Weather Stations, Justin Adam Lathlean, David J. Ayre Prof, Todd E. Minchinton

Faculty of Science - Papers (Archive)

Predicting how both spatial and temporal variation in sea and air temperature influence the distribution of intertidal organisms is a pressing issue. We used data from satellites, weather stations and in situ loggers to test the hypothesis that satellite-derived sea surface temperatures (SSTs) and weather station air temperatures provide accurate estimates of ambient temperature variability on rocky intertidal shores for temporal (hourly for 1 yr) and spatial (10 m to 400 km) variation along the southeast coast of Australia. We also tested whether satellites and weather stations accurately detect the duration, frequency and number of extreme temperature events. Daily mean …


Ordway Weather And Water Data 2011, Macalester College Jan 2011

Ordway Weather And Water Data 2011, Macalester College

Ordway Weather Data

Contains daily readings for the year indicated. The values include: PAR umol/s/m2, avg wind dir degree, avg windspeed mph, Avg Max Windspeed mph, Avg airtemp C, Avg RH %, Avg BP mmHg, Avg DailyRain in, Avg Rain Duration sec, Avg RainIntensity in/h, Avg Water Temp F, Avg sp cond mS/cm, avg pH, Avg Turb NTU+, Avg ODOSat %, Avg ODO mg/L, Water station PAR umol/s/m2, Avg Water Level m. File format: CSV.


Summary Tables: City Of Hampton, Virginia Shoreline Inventory Report, Marcia Berman, Harry Berquist, Sharon Killeen, Carl Hershner, Karinna Nunez, Karen Reay, Tamia Rudnicky Jan 2011

Summary Tables: City Of Hampton, Virginia Shoreline Inventory Report, Marcia Berman, Harry Berquist, Sharon Killeen, Carl Hershner, Karinna Nunez, Karen Reay, Tamia Rudnicky

Reports

The Shoreline Inventory Summary Tables quantify observed conditions based on river systems, such as the combined length of linear features (e.g. shoreline miles surveyed, miles of bulkhead and revetment), the total number of point features (e.g. docks, boathouses, boat ramps) & total acres of polygon features (tidal marshes).


Gis Data: City Of Hampton, Virginia Shoreline Inventory Report, Marcia Berman, Harry Berquist, Sharon Killeen, Carl Hershner, Karinna Nunez, Karen Reay, Tamia Rudnicky Jan 2011

Gis Data: City Of Hampton, Virginia Shoreline Inventory Report, Marcia Berman, Harry Berquist, Sharon Killeen, Carl Hershner, Karinna Nunez, Karen Reay, Tamia Rudnicky

Data

The data inventory developed for the Shoreline Inventory is based on a three‑tiered shoreline assessment approach. In most cases this assessment characterizes conditions that can be observed from a small boat navigating along the shoreline. The three tiered shoreline assessment approach divides the shorezone into three regions: 1) the immediate riparian zone, evaluated for land use; 2) the bank, evaluated for height, stability, cover and natural protection; and 3) the shoreline, describing the presence of shoreline structures for shore protection and recreational purposes. Hand-held GPS units are used to log features observed in the field.

Three GIS coverages are developed …


Gis Data: Northampton County, Virginia Tidal Marsh Inventory, Marcia Berman, Harry Berquist, Sharon Killeen, Carl Hershner, Karinna Nunez, Karen Reay, Tamia Rudnicky, Daniel E. Schatt Jan 2011

Gis Data: Northampton County, Virginia Tidal Marsh Inventory, Marcia Berman, Harry Berquist, Sharon Killeen, Carl Hershner, Karinna Nunez, Karen Reay, Tamia Rudnicky, Daniel E. Schatt

Data

The 2012 Tidal Marsh Inventory update for Northampton County, Virginia was generated using on-screen digitizing techniques in the most recent version of ArcGIS® - ArcMap while viewing conditions observed in the most recent imagery from the Virginia Base Mapping Program (VBMP). Dominant plant community types were primarily determined during field surveys from shallow-draft boats moving along the shoreline. Land-based surveys were performed in some locations. One shapefile is developed that portrays tidal marsh areas represented as polygons. A metadata file accompanies the shapefile to define attribute accuracy, data development, and any use restrictions that pertain to the data.