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Full-Text Articles in Physical Sciences and Mathematics

Software Development For A Three-Dimensional Gravity Inversion And Application To Study Of The Border Ranges Fault System, South-Central Alaska, Rolando Cardenas Jan 2011

Software Development For A Three-Dimensional Gravity Inversion And Application To Study Of The Border Ranges Fault System, South-Central Alaska, Rolando Cardenas

Open Access Theses & Dissertations

The Border Ranges Fault System (BRFS) bounds the Cook Inlet and Susitna Basins, an important petroleum province within south-central Alaska. A primary goal in the research is to test several plausible models of structure along the Border Ranges Fault System using a novel three-dimensional inversion utilizing gravity and magnetic data, constrained with other geophysical, borehole and surface geological information. This research involves the development of inversion modeling software using a Borland C++ compiler as part of the Rapid Application Development (RAD) Studio. The novel inversion approach directly models known geology, and "a priori" uncertainties on the geologic model to allow …


Specification Of Data Properties To Identify Anomalies In Scientific Sensor Data, Irbis Gallegos Jan 2011

Specification Of Data Properties To Identify Anomalies In Scientific Sensor Data, Irbis Gallegos

Open Access Theses & Dissertations

Environmental scientists use advanced sensor technology such as meteorological towers, wireless sensor networks and robotic trams equipped with sensors to perform data collection at remote research sites. Because the amount of environmental sensor data acquired by such instruments is increasing, the ability to evaluate the accuracy of the data at collection time and to check that the instrumentation is operating correctly become critical in order to not lose valuable time and information. The goal of the research is to define a solution, based on software-engineering techniques, to support the scientist's ability to specify data properties that can identify anomalies in …


Estimating Statistical Characteristics Under Interval Uncertainty And Constraints: Mean, Variance, Covariance, And Correlation, Ali Jalal-Kamali Jan 2011

Estimating Statistical Characteristics Under Interval Uncertainty And Constraints: Mean, Variance, Covariance, And Correlation, Ali Jalal-Kamali

Open Access Theses & Dissertations

In many practical situations, we have a sample of objects of a given type. When we measure the values of a certain quantity x for these objects, we get a sequence of values x1, . . . , xn. When the sample is large enough, then the arithmetic mean E of the values xi is a good approximation for the average value of this quantity for all the objects from this class. Other expressions provide a good approximation to statistical characteristics such as variance, covariance, and correlation.

The values xi come from measurements, and measurement is never absolutely accurate.

Often, …


Prediction Of Ribonucleic Acid Secondary Structures Using A Heuristic Backtracking Search, Christopher Roman Cuellar Jan 2011

Prediction Of Ribonucleic Acid Secondary Structures Using A Heuristic Backtracking Search, Christopher Roman Cuellar

Open Access Theses & Dissertations

Ribonucleic acid (RNA) is essential for all forms of life. RNA is made up of a large chain of nucleotide bases: Guanine (G), Uracil (U), Cytosine (C), and Adenine (A). An RNA strand can fold on itself to allow G-C, A-U, and G-U bases to form hydrogen bonds, this is known as a secondary structure. Knowing the secondary structure of an RNA chain is very important because it will allow researchers to better understand its specific functions. RNA will create secondary structures that tend to minimize their free energy. RNA secondary structure prediction is the attempt to predict physical folding …


A Web Site-Level Implementation Of Owl Sameas Predicate In Drupal, Patricia Esparza Jan 2011

A Web Site-Level Implementation Of Owl Sameas Predicate In Drupal, Patricia Esparza

Open Access Theses & Dissertations

The Ontology Web Language (OWL) sameAs predicate states that if the predicate holds between two Uniform Resource Identifiers (URIs) A and B, then an object identified by A is the same object identified by B; its purpose is to enable machines to understand that both objects are the same although they may have distinct Web identifiers, i.e., URIs. The proliferation of the use of this predicate has brought several issues to the Web, e.g., high cost of manually creating sameAs statements, inconsistent use of the predicate leading to distinct objects to be identified as being a single object, and too …


Gpu Based Parallel Smoothing Of Seismic Tomography Models, Ivan Gris Jan 2011

Gpu Based Parallel Smoothing Of Seismic Tomography Models, Ivan Gris

Open Access Theses & Dissertations

Three-dimensional models of the velocity structure of the Earth's crust are an important and relevant factor for several types of analyses across disciplines. Crustal velocity models are also commonly used to analyze and search for different materials of interest or to determine and differentiate many aspects of life on Earth during different eras.

Seismic tomography techniques, both in two and three dimensions, perform image reconstruction of the crust of the Earth. Seismic tomography algorithms can calculate crustal velocity structure through inversion of traveltimes of seismic waves produced by natural events, such as earthquakes, or controlled source experiments, such as explosions. …


Assessing Data Quality In A Sensor Network For Environmental Monitoring, Gesuri Ramirez Jan 2011

Assessing Data Quality In A Sensor Network For Environmental Monitoring, Gesuri Ramirez

Open Access Theses & Dissertations

Assessing the quality of sensor data in environmental monitoring applications is important, as erroneous readings produced by malfunctioning sensors, calibration drift, and problematic climatic conditions, such as icing or dust, are common.Traditional data quality checking and correction is a painstaking manual process, so the development of automatic systems for this task is highly desirable.

This study investigates machine learning methods to identify and clean incorrect data from a real-world environmental sensor network, the Jornada Experimental Range, located in Southern New Mexico. We evaluated several learning algorithms and data replacement schemes, and developed a method to identify the problematic sensor. The …


Development Of Load Balancing Algorithm Based On Analysis Of Multi-Core Architecture On Beowulf Cluster, Damian Valles Jan 2011

Development Of Load Balancing Algorithm Based On Analysis Of Multi-Core Architecture On Beowulf Cluster, Damian Valles

Open Access Theses & Dissertations

In this work, analysis, and modeling were employed to improve the Linux Scheduler for HPC use. The performance throughput of a single compute-node of the 23 node Beowulf cluster, Virgo 2.0, was analyzed to find bottlenecks and limitations that affected performance in the processing hardware where each compute-node consisted of two quad-core processors with eight gigabytes of memory. The analysis was performed using the High Performance Linpack (HPL) benchmark.

In addition, the processing hardware of the compute-node was modeled using an Instruction per Cycle (IPC) metric that was estimated using linear regression. Modeling data was obtained by using the Tuning …


The Exploratory Value Of Agent-Based Models In Social Science, Ricardo Andress Rivera Jan 2011

The Exploratory Value Of Agent-Based Models In Social Science, Ricardo Andress Rivera

Open Access Theses & Dissertations

N/A


Algorithms For Training Large-Scale Linear Programming Support Vector Regression And Classification, Pablo Rivas Perea Jan 2011

Algorithms For Training Large-Scale Linear Programming Support Vector Regression And Classification, Pablo Rivas Perea

Open Access Theses & Dissertations

The main contribution of this dissertation is the development of a method to train a Support Vector Regression (SVR) model for the large-scale case where the number of training samples supersedes the computational resources. The proposed scheme consists of posing the SVR problem entirely as a Linear Programming (LP) problem and on the development of a sequential optimization method based on variables decomposition, constraints decomposition, and the use of primal-dual interior point methods. Experimental results demonstrate that the proposed approach has comparable performance with other SV-based classifiers. Particularly, experiments demonstrate that as the problem size increases, the sparser the solution …


A Symbolic Approach Towards Constraint Based Software Verification, Shubhra Datta Jan 2011

A Symbolic Approach Towards Constraint Based Software Verification, Shubhra Datta

Open Access Theses & Dissertations

Verification and validation (V&V) are two components of the software engineering process that are critical to achieve reliability that can account for up to 50% of the cost of software development. Numerous techniques ranging from formal proofs to testing methods exist to verify whether programs conform to their specifications. Recently, constraint programming techniques for V&V have emerged : they use the idea of proof by contradiction. They typically aim at proving that the code is inconsistent with the negation of the specification, which means that the software conforms to its specifications. Although the framework seems straightforward, the number of generated …


Development Of An Expert System To Aid In The Selection Of Sustainability Design Engineering Methods, Pedro Renato Acosta Jan 2011

Development Of An Expert System To Aid In The Selection Of Sustainability Design Engineering Methods, Pedro Renato Acosta

Open Access Theses & Dissertations

The objective of this thesis is to present the development of an expert system to aid designers in the selection of design methods, in particular for sustainability methods. When practicing engineers need help in their design process, they look for design methods and tools; this is a challenge especially for inexperienced engineers in the sustainability area. Engineers, due to time constrains, will only utilize one or few methods during their professional life. The origin of this situation can be traced to engineering education, where it is typical that an instructor prefers one or few methods in particular, and even when …


Development And Testing Of An Unmanned Aircraft System For Environmental Science, Jerald James Brady Jan 2011

Development And Testing Of An Unmanned Aircraft System For Environmental Science, Jerald James Brady

Open Access Theses & Dissertations

For some environmental science applications, Unmanned Aircraft Systems (UASs) are increasingly recognized for their capacity to collect remotely sensed data in a safer, more efficient and effective manner than is permitted with manned aircraft and satellite remote sensing platforms. To date, however, technological, human, and other challenges have constrained adoption of UASs in the environmental sciences. This study developed and tested a new UAS for an archetypical environmental science research group (stakeholder) composed of non-UAS experts. Specifically, this thesis: 1) Assessed the research and operational needs of the stakeholder to determine the optimum UAS platform; 2) Developed an Unmanned Aerial …


Decentralized Fault Tolerant Caching With Memcached, Bivas Das Jan 2011

Decentralized Fault Tolerant Caching With Memcached, Bivas Das

Open Access Theses & Dissertations

Recent changes in web trends not only have increased popularity of web services, but also have vastly increased usage. Popular techniques, such as web-caching, used by content and service providers to provide faster content delivery at user end, is not enough to keep up, due to diversity and dynamic nature of web-contents.

Emerging ideas to cache on the server side, for faster content generation and delivery, is currently in use by popular web-service providers. One example of such caching system is Memcached. However, memcached, a distributed high performance caching system, is ineective in dynamic organization of itself and scaling when …