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Articles 1591 - 1620 of 1816
Full-Text Articles in Physical Sciences and Mathematics
Biodegradation Of Pah Contaminated Soil And Sludge Using Non-Ionic Surfactants, Seema Narula
Biodegradation Of Pah Contaminated Soil And Sludge Using Non-Ionic Surfactants, Seema Narula
Dissertations
Polycyclic aromatic hydrocarbons (PAHs) are one of the most prevalent environmental pollutants contaminating a large number of industrial and Superfund sites. Low solubility and sorption to solid surfaces limit biodegradation rates of PAHs in the environment. Bioremediation of these compounds have been previously tested with partial success. In the present study, aerobic biodegradation of three PAHs (fluorene, phenanthrene, and pyrene) has been studied in shaker flasks, batch fermenter, and bioslurry reactor, in the presence of non-ionic surfactants. A mixed bacterial culture derived from both a refinery sludge and an activated sludge was used as the seed population in the degradation …
Flag : The Fault-Line Analytic Graph And Fingerprint Classification, Ching-Yu Huang
Flag : The Fault-Line Analytic Graph And Fingerprint Classification, Ching-Yu Huang
Dissertations
Fingerprints can be classified into millions of groups by quantitative measurements of their new representations - Fault-Line Analytic Graphs (FLAG), which describe the relationship between ridge flows and singular points. This new model is highly mathematical, therefore, human interpretation can be reduced to a minimum and the time of identification can be significantly reduced.
There are some well known features on fingerprints such as singular points, cores and deltas, which are global features which characterize the fingerprint pattern class, and minutiae which are the local features which characterize an individual fingerprint image. Singular points are more important than minutiae when …
Effects Of Surfactants And Fenton's Reagents On Extraction And Destruction Of Phenanthrene In Spiked Sand, Ming-Chin Chang
Effects Of Surfactants And Fenton's Reagents On Extraction And Destruction Of Phenanthrene In Spiked Sand, Ming-Chin Chang
Dissertations
In this study, surfactants and Fenton's reagents (Fe(II) and H202) ere proposed to solve contaminated site problems in situ on a lab scale. Phenanthrene is a simple PAHs (polynuclear aromatic hydrocarbons). The phenanthrene spiked ottawa sand simulated contaminated soil. HPLC was used for phenanthrene analysis because it provided excellent separation and no interference. Six surfactants (including nonionic and ionic) were tested. The operating conditions were optimized based on process and economic considerations such as reaction time, mixing speed, concentrations of surfactants and concentrations of Fenton's reagents. Surfactants could effectively dissolve phenanthrene from the spiked sand. In …
Mechanistic Studies Of Cation Photogeneration, Mary Frances Clifton
Mechanistic Studies Of Cation Photogeneration, Mary Frances Clifton
Dissertations
No abstract provided.
Biophysical Studies Of The Spectrin Sequence Motif, Denise M. Lusitani
Biophysical Studies Of The Spectrin Sequence Motif, Denise M. Lusitani
Dissertations
No abstract provided.
Collision Spectroscopy Of Low Energy Capture By Multiply Charged Ions From Atomic Targets, Kadir Akgungor
Collision Spectroscopy Of Low Energy Capture By Multiply Charged Ions From Atomic Targets, Kadir Akgungor
Dissertations
State-selective differential cross sections for single-electron capture processes in very slow collisions of Ar^q+ (q = 4 - 6) ions with Ne, and Ar^6+ ions with He have been studied experimentally at laboratory collision energies between 15 and 100 qeV, and at scattering angles between 0° and 8° by means of translational energy-gain spectroscopy technique. The translational energy spectra show that only a few final states are populated depending on the charge state of the projectile, the projectile laboratory scattering angle, and the collision energy. These measurements also show that the dominant reaction channels are due to capture into excited …
An Integrated Environment For Problem Solving And Program Development, Fadi Pierre Deek
An Integrated Environment For Problem Solving And Program Development, Fadi Pierre Deek
Dissertations
A framework for an integrated problem solving and program development environment that addresses the needs of students learning programming is proposed. Several objectives have been accomplished: defining the tasks required for program development and a literature review to determine the actual difficulties involved in learning those tasks. A comprehensive Study of environments and tools developed to support the learning of problem solving and programming was then performed, covering programming environments, debugging aids, intelligent tutoring systems, and intelligent programming environments. This was followed by a careful analysis and critique of these systems, which uncovered the limitations that have prevented them from …
Modeling Study On The Neopentyl+ O2 Reaction System And Experimental And Modeling Study On Mtbe Pyrolysis And Oxidation, Ru Wei
Dissertations
A modeling study on neopentyl radical + O2 reaction system is conducted in this study. Thermodynamic parameters on all species and important transition states are calculated. A thermochemical kinetic analysis is performed.
Thermodynamic parameters are estimated using group additivity with HBI groups. Transition state energies are evaluated from experimental and theoretical data in the literature, combined with elementary reaction modeling to account for temperature effects. Transition state structures, vibration frequencies and entropies are determined from semi-empirical calculations, MOPAC PM3. Kinetics are analyzed with quantum RRK theory for k(E) coupled with modified strong collision analysis of Gilbert et al for …
Diffusive And Wavelike Phenomena In Thermal Processing Of Materials, John A. Pelesko
Diffusive And Wavelike Phenomena In Thermal Processing Of Materials, John A. Pelesko
Dissertations
Contemporary materials science abounds with novel processing methods. Devices such as lasers, microwave sources, and electron beam guns, provide unprecedented control over the deposition of energy within a material. The modern materials scientist has the ability to deposit energy volumetrically, to precisely control the location of energy deposition within a material, and to deposit energy in extremely short intervals of time. While making possible numerous thermal processing methods, these devices also push the limits of our understanding of the response of materials to energy deposition. In order to optimize and control these processing methods, it becomes necessary to further our …
Systematics Of Stable Isotopes And Radionuclides In Precipitation At Kalamazoo, Michigan, Usa, Madhav V. Machavaram
Systematics Of Stable Isotopes And Radionuclides In Precipitation At Kalamazoo, Michigan, Usa, Madhav V. Machavaram
Dissertations
Precipitation samples were collected at Kalamazoo from June 1992 to March 1995. The samples were analyzed for their 8D and 8lgO values. The 5D - 5I80 relationship is comparable to that of Meteoric Water Line (MWL). The monthly mean isotopic values in precipitation exhibited strong seasonality, being higher in summer and lower in winter months. This behavior is apparently a direct consequence of the temperature effect on isotope fractionation.
The summer precipitation at Kalamazoo is derived predominantly from the water vapor originated in the Gulf of Mexico. A box model calculation showed that a Rayleigh type distillation with Gulf moisture …
Localization And Transport Effects In The Disordered Materials, Vladislav Malyshkin
Localization And Transport Effects In The Disordered Materials, Vladislav Malyshkin
Dissertations
No abstract provided.
A Robust Estimate For An Autoregressive Time Series, Jeffrey Terpstra
A Robust Estimate For An Autoregressive Time Series, Jeffrey Terpstra
Dissertations
A weighted rank-based estimate for estimating the parameter of an auto-regressive time series is considered. When the weights are constant, the estimate is equivalent to using Jaeckel’s estimate and Wilcoxon scores. The estimate can be shown to be asymptotically normal at rate y/n. In a linear regression setting this estimate has the desired properties of a continuous totally bounded influence function and a positive breakdown point. It is shown via examples and Monte Carlo that these properties are preserved in an autoregressive time series setting.
Domination In Digraphs, Lisa Hansen
Bandwidth, Edgesum And Profile Of Graphs, Yung-Ling Lai
Bandwidth, Edgesum And Profile Of Graphs, Yung-Ling Lai
Dissertations
No abstract provided.
Groundwater-Kalamazoo River Interaction Near The Parchment City Wellfield, Parchment, Michigan, W. Richard Laton
Groundwater-Kalamazoo River Interaction Near The Parchment City Wellfield, Parchment, Michigan, W. Richard Laton
Dissertations
A detailed hydrogeologic study of the Kalamazoo River and its interaction with the groundwater was completed near Parchment, Michigan. The Kalamazoo River between Portage Creek and Allegan Dam is a Federal superfund site due to PCB contamination trapped in its sediments. The City of Parchment pumps all of its drinking water from a glacial aquifer 850 feet from the Kalamazoo River. This study focused on the hydrogeology and groundwater/surface interaction of the area through the use of surface and downhole geophysics, installation of monitoring wells and peizometers, seepage meters and chemical sampling. It was determined that the Kalamazoo River is …
Efficient Parallel Processing With Optical Interconnections, Lili Hai
Efficient Parallel Processing With Optical Interconnections, Lili Hai
Dissertations
With the advances in VLSI technology, it is now possible to build chips which can each contain thousands of processors. The efficiency of such chips in executing parallel algorithms heavily depends on the interconnection topology of the processors. It is not possible to build a fully interconnected network of processors with constant fan-in/fan-out using electrical interconnections. Free space optics is a remedy to this limitation. Qualities exclusive to the optical medium are its ability to be directed for propagation in free space and the property that optical channels can cross in space without any interference. In this thesis, we present …
An Investigation Of The Oxygraphic Response Of Stressed Bovine Blood, Cristin Mckenna
An Investigation Of The Oxygraphic Response Of Stressed Bovine Blood, Cristin Mckenna
Dissertations
Oxygraphic profiles of stressed bovine blood in a temperature controlled 2 ml reactor vessel provide the basis for an investigation of blood's response to various conditions. This response is broken down into an initial response (within 3 seconds), the response over 1 hour and the response over 24 hours. Fast-assay runs which investigate the initial response display a dose-response relationship when chemically stressed by phenol. Phenol concentrations in the 1,000 ppm range indicate a decrease in dissolved oxygen (DO) and higher phenol concentrations of over 20,000 an increase in DO. In addition to phenol concentration, other factors investigated with respect …
Multi-Wavelength Infrared Imaging Computer Systems And Applications, Jun Li
Multi-Wavelength Infrared Imaging Computer Systems And Applications, Jun Li
Dissertations
This dissertation presents the development of three computer systems for multi-wavelength thermal imaging.
Two computer systems were developed for the multi-wavelength imaging pyrometers (M-WIPs) that yield non-contact temperature measurements by remotely sensing the surface of objects with unknown wavelength-dependent emissivity. These M-WIP computer systems represent the state-of-art development in remote temperature measurement system based on the multi-wavelength approach. The dissertation research includes M-WIP computer system integration, software development, performance evaluation, and also applications in monitoring and control of temperature distribution of silicon wafers in a rapid thermal process system.
The two M-WIPs are capable of data acquisition, signal processing, system …
High Speed Protocols For Dual Bus And Dual Ring Network Architectures, Yaling Zhou
High Speed Protocols For Dual Bus And Dual Ring Network Architectures, Yaling Zhou
Dissertations
In this dissertation, two channel access mechanisms providing fair and bandwidth efficient transmission on dual bus and dual ring networks with high bandwidth-latency product are proposed. In addition, two effective priority mechanisms are introduced to meet the throughput and delay requirements of the diverse arrays of applications that future high speed networks must support.
For dual bus architectures, the Buffer Insertion Bandwidth Balancing (BI_BWB) mechanism and the Preemptive priority Bandwidth Balancing (P_BI_BWB) mechanism are proposed. BI_BWB can significantly improve the delay performance of remote stations. It achieves that by providing each station with a shift register into which the station …
Sampling And Analysis Of Trace Level Volatile Organic Compounds From Air Via Membrane Permeation, Naihong Zhu
Sampling And Analysis Of Trace Level Volatile Organic Compounds From Air Via Membrane Permeation, Naihong Zhu
Dissertations
The objective of this study is to develop air sampling techniques using membrane permeation. Two novel techniques for sampling and analysis of trace level VOCs from air via membrane permeation are presented:
- selective concentration of VOCs into a canister using a membrane permeator;
- on-line membrane extraction for direct introduction of VOCs from air emissions into a gas chromatograph.
In the membrane permeator-canister sampling system (MPCS), the air sample containing trace level VOCs as well as some interferences such as moisture are passed through the membrane module. Polydimethyl siloxane membrane used in this research is highly permeable to organic compounds, but …
On Document Filing Based Upon Predicates, Zhijian Zhu
On Document Filing Based Upon Predicates, Zhijian Zhu
Dissertations
This dissertation presents a formal approach to modeling documents in a personal office environment, proposes a heterogeneous algebraic query language to manipulating objects (folders) in the document model, and investigates a predicate-driven document filing system for automatically filing documents.
The document model was initially proposed in [38] which adopts a very natural view for describing the office documents using the relational and object-oriented paradigms. The model employs a dual approach to classifying and categorizing office documents by defining both a document type hierarchy and a folder organization. This dissertation extends and specifies formally the document model. Documents are partitioned into …
Reconstruction Of Wetland Hydrology Dynamics Using Tree Rings, Allan P. Hascall Iii
Reconstruction Of Wetland Hydrology Dynamics Using Tree Rings, Allan P. Hascall Iii
Dissertations
Increment core samples were collected and examined to test the hypothesis that the history of punctuated or intermediate-term changes in wetland soil-moisture conditions can be reconstructed from the annual growth-ring record of trees. The hypothesis is based on plant physiological principles that indicate a relationship between water surplus stress and impaired physiological activity that could lead to reduced growth.
Sampling sites were selected for their ostensible historic hydrologic variability and the availability of documentation of hydrologic disturbances. A conceptual model was developed by which trees were sampled along a hydrotopographic gradient for comparison of radial stem growth in uplands versus …
Study Of Impurity Modes In Photonic Crystals And Study Of Power Gaas Mesfets, Michael G. Khazhinsky
Study Of Impurity Modes In Photonic Crystals And Study Of Power Gaas Mesfets, Michael G. Khazhinsky
Dissertations
The dissertation consists of two projects. In the first project, impurity modes in Photonic Crystals are studied in one- and two-dimensional Photonic Crystals. Onedimensional systems are formed from an infinite layered array of dielectric slabs and are studied for linearly polarized electromagnetic waves propagating perpendicular to the plane of slabs. Two-dimensional systems consist either of parallel cylindrical dielectric rods in vacuum or cylindrical holes containing vacuum in dielectric medium. These rods/holes are arranged in a square lattice array. The electromagnetic waves in these system propagate perpendicular to the axes of the rods and are of E or H polarization. Green’s …
Least Space-Time First Scheduling Algorithm : Scheduling Complex Tasks With Hard Deadline On Parallel Machines, Bo-Chao Cheng
Least Space-Time First Scheduling Algorithm : Scheduling Complex Tasks With Hard Deadline On Parallel Machines, Bo-Chao Cheng
Dissertations
Both time constraints and logical correctness are essential to real-time systems and failure to specify and observe a time constraint may result in disaster. Two orthogonal issues arise in the design and analysis of real-time systems: one is the specification of the system, and the semantic model describing the properties of real-time programs; the other is the scheduling and allocation of resources that may be shared by real-time program modules.
The problem of scheduling tasks with precedence and timing constraints onto a set of processors in a way that minimizes maximum tardiness is here considered. A new scheduling heuristic, Least …
Massively Parallel Reasoning In Transitive Relationship Hierarchies, Yugyung Lee
Massively Parallel Reasoning In Transitive Relationship Hierarchies, Yugyung Lee
Dissertations
This research focuses on building a parallel knowledge representation and reasoning system for the purpose of making progress in realizing human-like intelligence. To achieve human-like intelligence, it is necessary to model human reasoning processes by programs. Knowledge in the real world is huge in size, complex in structure, and is also constantly changing even in limited domains. Unfortunately, reasoning algorithms are very often intractable, which means that they are too slow for any practical applications. One technique to deal with this problem is to design special-purpose reasoners. Many past Al systems have worked rather nicely for limited problem sizes, but …
Safe Code Transfromations For Speculative Execution In Real-Time Systems, Mohamed Mohamed Younis
Safe Code Transfromations For Speculative Execution In Real-Time Systems, Mohamed Mohamed Younis
Dissertations
Although compiler optimization techniques are standard and successful in non-real-time systems, if naively applied, they can destroy safety guarantees and deadlines in hard real-time systems. For this reason, real-time systems developers have tended to avoid automatic compiler optimization of their code. However, real-time applications in several areas have been growing substantially in size and complexity in recent years. This size and complexity makes it impossible for real-time programmers to write optimal code, and consequently indicates a need for compiler optimization. Recently researchers have developed or modified analyses and transformations to improve performance without degrading worst-case execution times. Moreover, these optimization …
Development Of Crosslinking Reagents, And Intra- And Intermolecular Multi-Linking Hemoglobin Molecules As Potential Blood Substitutes, Yaguo Zheng
Dissertations
No abstract provided.
Multinuclear Magnetic Resonance Studies Of Anion Binding To Copper, Zinc-Superoxide Dismutase, And Of Lithium Transport And Binding In Cultured Neuroblastoma Cells, Cherian Zachariah
Multinuclear Magnetic Resonance Studies Of Anion Binding To Copper, Zinc-Superoxide Dismutase, And Of Lithium Transport And Binding In Cultured Neuroblastoma Cells, Cherian Zachariah
Dissertations
No abstract provided.
Ionic Interaction Studies Of Bovine Copper, Zinc-Superoxide Dismutase, Hanan A. Hasan
Ionic Interaction Studies Of Bovine Copper, Zinc-Superoxide Dismutase, Hanan A. Hasan
Dissertations
No abstract provided.
The Computational Study Of "Model" Pollutants In Clay Montmorillonite, Sung-Ho Park
The Computational Study Of "Model" Pollutants In Clay Montmorillonite, Sung-Ho Park
Dissertations
No abstract provided.