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The Impact Of Overfitting And Overgeneralization On The Classification Accuracy In Data Mining, Huy Nguyen Anh Pham 2010 Louisiana State University and Agricultural and Mechanical College

The Impact Of Overfitting And Overgeneralization On The Classification Accuracy In Data Mining, Huy Nguyen Anh Pham

LSU Doctoral Dissertations

Current classification approaches usually do not try to achieve a balance between fitting and generalization when they infer models from training data. Such approaches ignore the possibility of different penalty costs for the false-positive, false-negative, and unclassifiable types. Thus, their performances may not be optimal or may even be coincidental. This dissertation analyzes the above issues in depth. It also proposes two new approaches called the Homogeneity-Based Algorithm (HBA) and the Convexity-Based Algorithm (CBA) to address these issues. These new approaches aim at optimally balancing the data fitting and generalization behaviors of models when some traditional classification approaches are used ...


Mesoporous Silica Nanoparticles: Structural Design And Applications, Igor I. Slowing, Juan Luis Vivero-escoto, Brian G. Trewyn, Victor S.Y. Lin 2010 Iowa State University

Mesoporous Silica Nanoparticles: Structural Design And Applications, Igor I. Slowing, Juan Luis Vivero-Escoto, Brian G. Trewyn, Victor S.Y. Lin

Chemistry Publications

The structural properties of mesoporous silica nanoparticles are reviewed. Different strategies for the introduction of functional groups are considered. Based on the architectural features of the material, the functionalization at defined regions of the particles is described, along with the properties emerging from the corresponding site-specific modifications of their chemistry. Many applications derived from the unique architecture and chemistry of these nanostructured composite materials are shown.


An Adaptable Group Communication System, Vikram Reddy Kayathi 2010 Louisiana State University and Agricultural and Mechanical College

An Adaptable Group Communication System, Vikram Reddy Kayathi

LSU Master's Theses

Existing group communication systems like ISIS, Spread, Jgroups etc., provide group communication in a synchronous environment. They are built on top of TCP/IP or UDP and guarantee virtual synchrony and consistency. However, wide area distributed systems are inherently asynchronous. Existing group communication systems are not suitable for wide area deployment. They do not provide persistent communication; i.e., if a node gets temporarily disconnected, all messages directed to that node during that period are lost. Hence such systems are not suitable for deployment in disadvantaged networks. While, according to Brewer’s CAP theorem, it is impossible for a distributed ...


Effective Use Of Web-Based Homework In High School Physics, Elizabeth Pullig Hitt 2010 Louisiana State University and Agricultural and Mechanical College

Effective Use Of Web-Based Homework In High School Physics, Elizabeth Pullig Hitt

LSU Master's Theses

High school physics tests and web-based homework grades were analyzed to determine if web-based homework improves test grades; if the number of web assignments before a test affects the test grade; and if the length of the web assignment affects the number of students that complete the homework assignment. The test grades of students who did their homework were compared to test grades of students who did not do their homework; the assumption was that doing web-based homework improved test grades at this school during the four years studied. The homework group scored seven points higher on average than the ...


K23au12sn9—An Intermetallic Compound Containing A Large Gold−Tin Cluster: Synthesis, Structure, And Bonding, Bin Li, Sung-Jin Kim, Gordon J. Miller, John D. Corbett 2010 Iowa State University

K23au12sn9—An Intermetallic Compound Containing A Large Gold−Tin Cluster: Synthesis, Structure, And Bonding, Bin Li, Sung-Jin Kim, Gordon J. Miller, John D. Corbett

Chemistry Publications

A polyanionic unit {Au12Sn9} with a novel “corrugated sheet” shape occurs in K23Au12Sn9. The compound was obtained by fusion of the pure elements in tantalum ampules at high temperatures followed by programmed cooling, and the structure was determined by X-ray diffraction: I4̅2m (No. 121), a = 20.834(3), c = 6.818(1) Å, Z = 2. The large heteroatomic cluster has D2d point symmetry and features a central four bonded (4b-) Sn, eight 3b- or 2b-Sn on the perimeter, and 24 linking nearly linear ...


Pd2.28(1)Zn10.37(1)Al0.35(1), A Ternary Y-Brass-Type Structure, Srinivasa Thimmaiah, Gordon J. Miller 2010 Iowa State University

Pd2.28(1)Zn10.37(1)Al0.35(1), A Ternary Y-Brass-Type Structure, Srinivasa Thimmaiah, Gordon J. Miller

Chemistry Publications

No abstract provided.


Influence Of Y Substitutions On The Magnetism Of Gd5ge4, Durga Paudyal, Yaroslav Mudryk, Vitalij K. Pecharsky, Sumohan Misra, Gordon J. Miller, Karl A. Gschneidner Jr. 2010 Iowa State University

Influence Of Y Substitutions On The Magnetism Of Gd5ge4, Durga Paudyal, Yaroslav Mudryk, Vitalij K. Pecharsky, Sumohan Misra, Gordon J. Miller, Karl A. Gschneidner Jr.

Chemistry Publications

The interrelation between the specific crystallographic positions and their influence on the magnetism of neighboring atoms is examined from first principles electronic structure calculations using the Gd5Ge4 compound as a model system. The predicted preferences of the specific occupations by nonmagnetic yttrium atoms and the resulting magnetism of substituted Gd5Ge4 have been confirmed, respectively, by single crystal x-ray diffraction and magnetization experiments.


Controlling Magnetism Of A Complex Metallic System Using Atomic Individualism, Yaroslav Mudryk, Durga Paudyal, Vitalij K. Pecharsky, Karl A. Gschneidner Jr., Sumohan Misra, Gordon J. Miller 2010 Iowa State University

Controlling Magnetism Of A Complex Metallic System Using Atomic Individualism, Yaroslav Mudryk, Durga Paudyal, Vitalij K. Pecharsky, Karl A. Gschneidner Jr., Sumohan Misra, Gordon J. Miller

Chemistry Publications

When the complexity of a metallic compound reaches a certain level, a specific location in the structure may be critically responsible for a given fundamental property of a material while other locations may not play as much of a role in determining such a property. The first-principles theory has pinpointed a critical location in the framework of a complex intermetallic compound—Gd5Ge4—that resulted in a controlled alteration of the magnetism of this compound using precise chemical tools.


Rhombohedrally Distorted Γ-Brasses Cr1−Xfexga, Hyujin Ko, Olivier Gourdon, Delphine Gout, Eun-Deok Mun, Srinivasa Thimmaiah, Gordon J. Miller 2010 Iowa State University

Rhombohedrally Distorted Γ-Brasses Cr1−Xfexga, Hyujin Ko, Olivier Gourdon, Delphine Gout, Eun-Deok Mun, Srinivasa Thimmaiah, Gordon J. Miller

Chemistry Publications

A series of rhombohedrally distorted γ-brass structures containing a mixture of magnetically active 3d elements, Cr and Fe, Cr1−xFexGa, is investigated crystallographically. These structures consist of chains of trans-face-sharing Ga-centered transition metal icosahedra. Neutron powder diffraction specifically on Cr0.5Fe0.5Ga, which could be prepared as a single phase material, gave lattice constants (11 K) a = 12.5172(2) Å and c = 7.8325(2) Å and a refined composition of Cr0.502(6)Fe0.498Ga = Cr6.523Fe6.477Ga13 and revealed partial ordering ...


Synthesis And Characterization Of Rare Earth-Nickel-Gallium Ternary Intermetallics, Kandace R. Thomas 2010 Louisiana State University and Agricultural and Mechanical College

Synthesis And Characterization Of Rare Earth-Nickel-Gallium Ternary Intermetallics, Kandace R. Thomas

LSU Doctoral Dissertations

The structural and physical characterization of several early and latter rare earth Ln-Ni-Ga systems, which include Ln2NiGa12 (Ln = Pr, Nd, Sm), alpha-LnNiGa4 (Ln = Y, Gd – Yb) and beta-LnNiGa4 (Ln = Tb – Ho) will be presented in this work. These systems are thermodynamically located within a copious, robust phase space and provide a rich understanding of how slight modifications to synthetic preparations can yield the adoption of different structure types in a Ga-rich regime. Each of these phases is made up of well-studied substructures which lend an additional angle of apperception as to how their structure and properties are related. Ln2MGa12 (Ln ...


Habitat Use, Movements And Spring Migration Chronology And Corridors Of Female Gadwalls That Winter Along The Louisiana Gulf Coast, Jacob M. Gray 2010 Louisiana State University and Agricultural and Mechanical College

Habitat Use, Movements And Spring Migration Chronology And Corridors Of Female Gadwalls That Winter Along The Louisiana Gulf Coast, Jacob M. Gray

LSU Master's Theses

The Louisiana Gulf Coast is an important wintering area for North American gadwall (Anas strepera). Conservation of winter habitat is a top priority of the Gulf Coast Joint Venture. Quantitative estimates of habitat use by wintering gadwall would help improve energetic demand models and subsequent estimates of habitat requirements. I used satellite telemetry (PTTs) to estimate winter habitat and refuge uses, spring migration chronology and corridors, as well as inter- and intra-regional winter movements of females. I used a split-plot MANOVA to evaluate the effects of individual females, female age, winter, hunt periods within winter, time of day, and all ...


A Functional And Ontogenetic Skull Analysis Of The Extant Rhinoceroses And Teleoceras Major, An Extinct Miocene North American Rhinoceros, Mark Daniel Hagge 2010 Louisiana State University and Agricultural and Mechanical College

A Functional And Ontogenetic Skull Analysis Of The Extant Rhinoceroses And Teleoceras Major, An Extinct Miocene North American Rhinoceros, Mark Daniel Hagge

LSU Master's Theses

Functional and ontogenetic skull differences among extant rhinoceroses and the extinct North American rhinoceros Teleoceras major were investigated to assess the unknown feeding ecology of Teleoceras. Ontogenetic skull sequences of the extant Indian rhino (Rhinoceros unicornis), Sumatran rhino (Dicerorhinus sumatrensis), white rhino (Ceratotherium simum), and black rhino (Diceros bicornis), and the extinct Miocene North American rhino T. major were gathered for both qualitative and quantitative assessments. Eleven functional characters related to specific feeding ecologies in extant perissodactyls were morphologically described, and each species’ skull development was described in detail. Nineteen linear skull measurements were taken across all specimens of all ...


Upland Nesting Waterfowl Population Responses To Predator Reduction In North Dakota, Matthew R. Pieron 2010 Louisiana State University and Agricultural and Mechanical College

Upland Nesting Waterfowl Population Responses To Predator Reduction In North Dakota, Matthew R. Pieron

LSU Doctoral Dissertations

Population growth for mallards (Anas platyrhynchos), and presumably other upland nesting ducks, in the Prairie Pothole Region is most sensitive to nest success, and nest success is most strongly influenced by predation. I evaluated the efficacy of reducing predator populations to improve nest success and increase local breeding populations of upland nesting ducks on township-sized (93.2 km2) management units in eastern North Dakota, USA, during 2005−2008. I also examined potential territorial limitations on local population growth for mallards. Trappers annually removed an average of 245 predators per trapped site. I monitored 7,489 nests on 7 trapped and ...


The Effects Of A Freshwater Diversion Of Nekton Species Biomass Distributions, Food Web Pathways, And Community Structure In A Louisiana Estuary, Kim de Mutsert 2010 Louisiana State University and Agricultural and Mechanical College

The Effects Of A Freshwater Diversion Of Nekton Species Biomass Distributions, Food Web Pathways, And Community Structure In A Louisiana Estuary, Kim De Mutsert

LSU Doctoral Dissertations

A current method to restore Louisiana’s estuaries includes reintroducing freshwater and sediments to wetlands that are hydrologically isolated from the Mississippi River due to the construction of levees. In this dissertation, I examined effects of the second largest freshwater diversion in Louisiana, the Caernarvon Freshwater Diversion (CFD), on estuarine nekton in Breton Sound. Before focusing on Breton Sound, I examined the status of nekton communities in the northern Gulf of Mexico (GOM), and Louisiana wetlands in particular, using the mean trophic level index (MTLI). I demonstrated that commercial targeting caused the previously reported low and declining MTLI from the ...


Aqueous Solvation Of Bihalide Anions, Daniel David Kemp, Mark S. Gordon 2010 Iowa State University

Aqueous Solvation Of Bihalide Anions, Daniel David Kemp, Mark S. Gordon

Chemistry Publications

Second-order Møller−Plesset perturbation theory (MP2) is used to perform geometry optimizations on XHX−·(H2O)n for X = Br, I, with n = 1 to 6 water molecules. Of particular interest is the manner in which the solvent molecules orient themselves around the solute and which configurations are lowest in energy. Although for most values of n, water molecules may donate all of their hydrogen atoms for hydrogen bonding to the solute, this type of structure is the lowest in energy only for n = 0 to 2 and is only a local minimum for n = 3, 4, and 6. For n ...


Integration Of Paleotempestology With Coastal Risk And Vulnerability Assessment: Case Studies From The Dominican Republic And Nicaragua, Devyani Kar 2010 Louisiana State University and Agricultural and Mechanical College

Integration Of Paleotempestology With Coastal Risk And Vulnerability Assessment: Case Studies From The Dominican Republic And Nicaragua, Devyani Kar

LSU Doctoral Dissertations

Hurricanes account for a significant portion of damages, injuries, and fatalities in the Caribbean. The Dominican Republic has had 3 major hurricane strikes in this century resulting in loss of lives for thousands of people and billions of US $ in economic loss. Major hurricanes had been relatively infrequent in north-eastern Nicaragua’s modern history until Hurricane Felix, a Category 5 storm, made landfall in the north-east in 2007. It caused 130 confirmed deaths and brought devastation to many villages. These events highlight a need for re-evaluation of hurricane risk based on a more comprehensive and long-term hurricane history. Using paleotempestological ...


Data Transfer Scheduling With Advance Reservation And Provisioning, Mehmet Balman 2010 Louisiana State University and Agricultural and Mechanical College

Data Transfer Scheduling With Advance Reservation And Provisioning, Mehmet Balman

LSU Doctoral Dissertations

Over the years, scientific applications have become more complex and more data intensive. Although through the use of distributed resources the institutions and organizations gain access to the resources needed for their large-scale applications, complex middleware is required to orchestrate the use of these storage and network resources between collaborating parties, and to manage the end-to-end processing of data. We present a new data scheduling paradigm with advance reservation and provisioning. Our methodology provides a basis for provisioning end-to-end high performance data transfers which require integration between system, storage and network resources, and coordination between reservation managers and data transfer ...


Augmented Breast Tumor Classification By Perfusion Analysis, Bruce Yu-Sun Lin 2010 Louisiana State University and Agricultural and Mechanical College

Augmented Breast Tumor Classification By Perfusion Analysis, Bruce Yu-Sun Lin

LSU Doctoral Dissertations

Magnetic resonance and computed tomography imaging aid in the diagnosis and analysis of pathologic conditions. Blood flow, or perfusion, through a region of tissue can be computed from a time series of contrast-enhanced images. Perfusion is an important set of physiological parameters that reflect angiogenesis. In cancer, heightened angiogenesis is a key process in the growth and spread of tumorous masses. An automatic classification technique using recovered perfusion may prove to be a highly accurate diagnostic tool. Such a classification system would supplement existing histopathological tests, and help physicians to choose the most optimal treatment protocol. Perfusion is obtained through ...


Investigations Of Structure / Property Interrelationships Of Organic Thin Films Using Scanning Probe Microscopy And Nanolithography, Zorabel Mallorca LeJeune 2010 Louisiana State University and Agricultural and Mechanical College

Investigations Of Structure / Property Interrelationships Of Organic Thin Films Using Scanning Probe Microscopy And Nanolithography, Zorabel Mallorca Lejeune

LSU Doctoral Dissertations

Studies of the surface assembly and molecular organization of organic thin films were studied using scanning probe microscopy (SPM) and scanning probe lithography (SPL). Systems of organic thin films such as n-alkanethiols and pyridyl functionalized porphyrins were characterized at the molecular level, and measurements of the conductive properties of polythiophenes containing in-chain cobaltabisdicarbollides were accomplished. Understanding the self-organization and mechanisms of self-assembly of organic molecules provides fundamental insight for structure/property interrelationships. Investigations of the surface assembly of 5,10-diphenyl-15,20-di-pyridin-4-yl-porphyrin (DPP) on Au(111) were done using SPL methods of nanoshaving and nanografting. Automated computer designs were developed for ...


Chemistry Of Rhenium(I) Tricarbonyl Complexes Of Biomedical Relevance, Theshini Perera 2010 Louisiana State University and Agricultural and Mechanical College

Chemistry Of Rhenium(I) Tricarbonyl Complexes Of Biomedical Relevance, Theshini Perera

LSU Doctoral Dissertations

fac-[ReI(CO)3L]n complexes serve as models for short-lived fac-[99mTcI(CO)3L] imaging tracers. Dangling groups on L, needed to achieve desirable biodistribution, complicate the NMR spectra, which are not readily understood. In fac-[ReI(CO)3L]+ with less complicated L, NH groups (exo-NH) projecting toward the L face sometimes showed an upfield shift attributable to steric shielding of the exo-NH group from the solvent by the chelate rings. To investigate whether exo-NH groups in six-membered rings exhibit the same effect and whether the presence of dangling ...


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