Physical Sciences and Mathematics Commons^™

Rainbow Ramsey Numbers, Linda Eroh

Dissertations

No abstract provided.

An Investigation Into Relationships Between Alternative Assessment And Pre-Service Elementary Teachers’ Beliefs About Mathematics, David Charles Coffey

Dissertations

The purpose of this study was to examine how including alternative assessments in a reform-based mathematics course affects pre-service teachers’ mathematical beliefs. A single section of a mathematics course designed for elementary education majors that employed three different alternative assessments was the setting for the study.

A pre- and post-belief survey completed by students enrolled in the section under study represented the first level of data collection and analysis. The results of the pre-belief survey guided the selection of seven informants from the section and provided belief statements for the informants to verify during subsequent interviews. Based on the data …

Dtd-Miner: A Tool For Mining Dtds From Xml Documents, Moh Chuang Hue, Ee Peng Lim, Wee-Keong Ng

Research Collection School Of Computing and Information Systems

XML documents are semistructured and the structure of the documents is embedded in the tags. Although XML documents can be accompanied by a DTD that defines the structure of the documents, the presence of a DTD is not mandatory. The difficulty in deriving the DTD for XML documents lies in the fact that DTDs are of different syntax as XML and that prior knowledge of the structure of the documents is required. In this paper, we introduce DTD-Miner, an automatic structure-mining tool for XML documents. Using a Web-based interface, the user will be able to submit a set of similarly …

The Complexity Of Decentralized Control Of Markov Decision Processes, Daniel S. Bernstein, Shlolo Zilberstein, Neil Immerman

Neil Immerman

Planning for distributed agents with partial state information is considered from a decisiontheoretic perspective. We describe generalizations of both the MDP and POMDP models that allow for decentralized control. For even a small number of agents, the finite-horizon problems corresponding to both of our models are complete for nondeterministic exponential time. These complexity results illustrate a fundamental difference between centralized and decentralized control of Markov processes. In contrast to the MDP and POMDP problems, the problems we consider provably do not admit polynomialtime algorithms and most likely require doubly exponential time to solve in the worst case. We have thus …

Study Of Architecture And Protocols For Reliable Multicasting In Packet Switching Networks, Shiwen Chen

Dissertations

Group multicast protocols have been challenged to provide scalable solutions that meet the following requirements: (i) reliable delivery from different sources to all destinations within a multicast group; (ii) congestion control among multiple asynchronous sources. Although it is mainly a transport layer task, reliable group multicasting depends on routing architectures as well.

This dissertation covers issues of both network and transport layers. Two routing architectures, tree and ring, are surveyed with a comparative study of their routing costs and impact to upper layer performances. Correspondingly, two generic transport protocol models are established for performance study. The tree-based protocol is rate-based …

Time Domain Measurement Of The Nonlinear Refractive Index In Optical Fibers And Semiconductor Film, Hernando Garcia

Dissertations

A new technique to measure the nonlinear refractive index n₂ in optical fibers and semiconductor films has been developed. It is based on the time delay two-beam coupling of very intense picosecond laser pulses that have been self-phase modulated in the nonlinear optical medium. The two beams are coupled in a slow responding medium that is sensitive to time dependent phase distortions. We determine that the amount of phase distortion experienced by the pulse is proportional to the nonlinear refractive index of the medium, This time domain approach can also be applied to optical fiber amplifiers in the presence …

Genetically Evolved Dynamic Control For Quadruped Walking, Giorgio Grasso

Dissertations

The aim of this dissertation is to show that dynamic control of quadruped locomotion is achievable through the use of genetically evolved central pattern generators. This strategy is tested both in simulation and on a walking robot. The design of the walker has been chosen to be statically unstable, so that during motion less than three supporting feet may be in contact with the ground.

The control strategy adopted is capable of propelling the artificial walker at a forward locomotion speed of ~1.5 Km/h on rugged terrain and provides for stability of motion. The learning of walking, based on simulated …

Modeling, Design And Fabrication Of Thin-Film Microcrystalline Silicon Solar Cells, Wei Chen

Dissertations

The modeling, design and fabrication of low-cost thin-film microcrystalline silicon(µcSi) solar cells is studied in this thesis. The cell, considered in this investigation, utilizes low-cost glass as the substrate and microcrystalline Si (µc-Si) as the active layer. A comprehensive refractive index (n) and extinction coefficient (k) model of silicon as function of doping, temperature and wavelength is developed to assist the optical design of the cell. In order to obtain acceptable short circuit current density (Jsc) from the cell, it is found that the thickness of the silicon thin film should be more than 10µm. To get the best light …

A Meta-Semantic Language For Smart Component-Adapters, Leon K. Jololian

Dissertations

The issues confronting the software development community today are significantly different from the problems it faced only a decade ago. Advances in software development tools and technologies during the last two decades have greatly enhanced the ability to leverage large amounts of software for creating new applications through the reuse of software libraries and application frameworks. The problems facing organizations today are increasingly focused around systems integration and the creation of information flows.

Software modeling based on the assembly of reusable components to support software development has not been successfully implemented on a wide scale. Several models for reusable software …

Active Feedback Control Of A Wake Flow Via Forced Oscillations Based On A Reduced Model, Fu Li

Dissertations

As it is well known, the flow past a cylinder consists of a symmetric recirculation bubble of vortices at small Reynolds numbers. As Reynolds number increases, the bubble becomes unstable and develops into a Karman vortex street of alternating vortices. This instability is responsible for the occurrence of large amplitude oscillations in the lift and an increase in the mean drag. It was previously shown by numerical simulation that the mechanism driving the bubble instability is well mimicked by Foppl's four dimensional potential flow model where the bubble is represented by a saddle point. In this work, we design two …

Component-Based Software Engineering, Zhiyuan Wang

Dissertations

To solve the problems coming with the current software development methodologies, component-based software engineering has caught many researchers' attention recently. In component-based software engineering, a software system is considered as a set of software components assembled together instead of as a set of functions from the traditional perspective. Software components can be bought from third party vendors as off-the-shelf components and be assembled together.

Component-based software engineering, though very promising, needs to solve several core issues before it becomes a mature software development strategy. The goal of this dissertation is to establish an infrastructure for component-based software development. The author …

Applications Of Agent Architectures To Decision Support In Distributed Simulation And Training Systems, Plamen V. Petrov

Dissertations

This work develops the approach and presents the results of a new model for applying intelligent agents to complex distributed interactive simulation for command and control. In the framework of tactical command, control communications, computers and intelligence (C₄I), software agents provide a novel approach for efficient decision support and distributed interactive mission training. An agent-based architecture for decision support is designed, implemented and is applied in a distributed interactive simulation to significantly enhance the command and control training during simulated exercises. The architecture is based on monitoring, evaluation, and advice agents, which cooperate to provide alternatives to the …

Airflow Characteristics Of Commonly Used Temperature Radiation Shields*, X. Lin, Kenneth G. Hubbard, George E. Meyer

School of Natural Resources: Faculty Publications

The air temperature radiation shield is a key component in air temperature measurement in weather station networks; however, it is widely recognized that significant errors in the measured air temperature exist due to insufficient airflow past the air temperature sensor housed inside the shield. During the last several decades, the U.S. National Weather Service has employed a number of different shields in air temperature measurements. This paper focuses on the airflow characteristics inside air temperature shields including the Maximum–Minimum Temperature System (MMTS), the Gill shields, and the Cotton Region Shelter (CRS).

Average airspeed profiles and airflow efficiency inside the shields …

A Study Of Droplet Burning In The Nearly Adiabatic Limit, Juan C. Gomez

Dissertations

We consider a small drop of liquid fuel that burns in an oxidizing gaseous environment and translates slowly (relative to flow 'at infinity') under the action of gravity. Practical applications include the burning of liquid fuels as sprays in domestic and industrial oil-fired burners, diesel engines, and liquid-propellant rocket motors. More relevant to the simple physical set-up of the present study are wellcharacterized laboratory experiments on the burning of a single, isolated fuel drop.

The drop burns in a nearly spherical, diffusion flame, flame sheet regime. We consider a specific example, or limit, referred to as 'nearly adiabatic burning', in …

Numerical Study Of Particle Dynamics In A Falling-Ball Viscometer, Peiwen Hou

Dissertations

The falling-ball viscometer is a device where a spherical particle falls along the axis of a circular cylinder filled with viscous fluid. The various classical results for this device are developed under the assumption that the Reynolds number of the flow is zero, i.e., Stoke's flow. Inertial effects are not taken into account. To better understand the dynamics of the particle sedimentation process and the role of inertia in this process, we implemented a numerical simulation.

The ADI (Alternating Direction Implicit) scheme is widely used to solve the vorticity-stream function formulation of the Navier-Stokes equation in axisymmetric geometries. However, a …

Development And Characterization Of Techniques For Neuro-Imaging Registration, Carlo Ciulla

Theses

Three automated techniques were developed for the alignment of Neuro-Images acquired during distinct scanning periods and their performance were characterized. The techniques are based on the assumption that the human brain is a rigid body and will assume different positions during different scanning periods. One technique uses three fiducial markers, while the other two uses eigenvectors of the inertia matrix of the Neuro-Image, to compute the three angles (pitch, yaw and roll) needed to register the test Neuro-Image to the reference Neuro-Image. A rigid body transformation is computed and applied to the test Neuro-Image such that it results aligned to …

Thermochemical Properties Of Methyl And Chloro-Methyl Hyplochlorites And Ethers And Reaction Of Methyl Radical With Clo, Dawoon Jung

Theses

Hypochlorites are formed from reactions of chlorine monoxide (ClO) addition to unsaturates and association with radicals. ClO is a prevalent and an important species in chemistry of the atmosphere and in combustion systems where chlorine is present. Thermochemical property data on these oxy-chlorocarbon species are important to understanding the reaction pathways and kinetics in these environments. Enthalpy, ΔH_f°_298, entropy, S°_298, and heat capacities, C_p(T) from 300 to 1500 K are determined for methyl hypochlorite and three chloro-methyl hypochlorites and formaldehyde-C1 atomcomplex radicals (CH₂O--Cl, CHClO--CI, CCI₂O--Cl) by density functional, and ab …

Universal Access In Digital Libraries, Igg Adiwijaya

Theses

Digital libraries are concerned with the creation and management of information sources, the movement of information across global networks and the effective use of this information by a wide range of users. A digital library is a vast collection of obj ects that are of multimedia nature, e.g., text, video, images, and audio. Users wishing to access the digital library objects may possess varying capabilities, preferences, domain expertise, and may use different information appliances. With the phenomenal growth of the Internet, the number of different information appliances will, if not already, increase substantially in the near future. Facilitating access to …

Structures, Intermolecular Rotation Barriers, And Thermodynamic Properties Of Chlorinated Methanols And Chlorinated Methyl Hydroperoxides, Hongyan Sun

Theses

Thermochemical property data on chlorinated methanols and methyl hydroperoxides are important in oxidation, combustion and atmospheric photochemistry of chlorocarbons, Enthalpy, entropy, and heat capacities are determined for three chlorinated methanols and three chlorinated methyl hydroperoxides using density frnctional, B3LYP/6-31G(d,p), B3LYP/6-311+G(3df,2p), ab initio QCISD(T)/6-31G(d,p) and the composite CBSQ/B3LYP/6-31G(d,p) calculation methods. Molecular structures and vibration frequencies are determined at the B3LYP/6-31G(d,p) density functional calculation level. Vibration frequencies are scaled for zero point energies and for thermal corrections. ΔH°_{f 298} are determined at each calculation level using the ΔH_rxn,298 with known enthalpies of other reactants and products in each of five …

Lethal Control Of Piscivorous Birds At Aquaculture Facilities In The Northeast United States: Effects On Populations, Bradley F. Blackwell, Richard A. Dolbeer, Laura A. Tyson

United States Department of Agriculture Wildlife Services: Staff Publications

Predation by piscivorous birds is considered a substantial threat to the aquaculture industry. However, lethal control of birds at aquaculture facilities has raised concerns about the effects on the distribution and abundance of populations of the species killed. We examined the relationship between numbers of piscivorous birds reported killed under U.S. Fish and Wildlife Service (USFWS) permits at aquaculture facilities in New York, New Jersey, and Pennsylvania and species population trends within the respective states. The USFWS issued 26 permits to 9 facilities from 1985 through September 1997. Eight species appeared on permits, but only six species were reported killed: …

Diffractive Dijets With A Leading Antiproton In P̅P Collisions At √S = 1800 Gev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration

Kenneth Bloom Publications

We report results from a study of events with a leading antiproton of beam momentum fraction 0.905 <x_F < 0.965 and 4-momentum transfer squared |t|< 3 GeV² produced in p̅p collisions at √s =1800 GeV at the Fermilab Tevatron collider. Approximately 2% of the events contain two jets of transverse energy E_T^jet > 7 GeV. Using the dijet events, we evaluate the diffractive structure function of the antiproton and compare it with expectations based on results obtained in diffractive deep inelastic scattering experiments at the DESY ep collider HERA.

Powder Microelectrode Modified With Nafion-Os(Bpy)_3~( 2+) And Pvp Composite And Its Catalysis For No_2 - Reduction, Pei-Fang Liu, Jia-Wei Yan

Journal of Electrochemistry

The modified powder microelectrode was prepared by etching a Pt (0.1 mm diameter) disk microelectrode and filling in thus formed cavity with Nation_Os(bpy) 3 2+ /PVP composite modified carbon powder. The composite modified powder microelectrode showed cyclic voltammetric behaviors changing with the mole ratio (denoted X) of SO 3 - to Os(bpy) 3 2+ in Nafion. When X=3, a single pair of current peaks appeared near 0.6V (vs. SCE) due to Os(bpy) 3 2+/3+ redox couple. In contrast, for X=20, a pair of additional current peaks occurred near 0.4V. Both X=3 and X=20 modified powder microelectrodes strongly catalyzed the first …

The Studies On Nanosized Materials For Lithium Ion Batteries, Hong Li, Jing-Ze Li, Li-Hong Shi, Guang-Yan Zhu, Qing Chen, Wei Lu, Xue-Jie Huang, Li-Quan Chen

Journal of Electrochemistry

Our recent works about nanosized materials for lithium ion batteries are reported, including the synthesis of nanosized Sb, SnSb, CuSn x, Si and CuS, their electrochemical performance as anode or cathode active materials,the variation of crystal structure and morphology during discharge and charge cycling. In addition,the self_plasticization of lithium salt with nanosized anion ion in polymer electrolyte,the influence of the electrochemical Li_doping on the Raman spectra and photoluminescence of nano_Si are also introduced. Furthermore,the relationship between intrinsic properties of nanosized materials and their electrochemical behaviors are discussed. The prospect of nanosized materials for lithium ion batteries is drawn.

A Review On Impressed Current Anodes Of Cathodic Protection For Underground Structures, Li-Kun Xu, Ting-Yong Wang, Liang-Qian Qian Rong-Chun You, Guang-Zhang Chen

Journal of Electrochemistry

The requirements of impressed current anodes for the protection of underground structures were presented in this paper according to the analysis of working conditions. The characteristics and performance of various anodes such as scrap steel, graphite, high silicon cast iron, magnetite, platinized anode, conductive polymer cable anode and mixed metal oxide anode were reviewed. The development trend of impressed current anodes for underground applications was also discussed.

Technical Investigaton Of Thin-Film Plasticizing Lithium Ion Battery, Xin-Ping Ai, Xin-Lin Hong, Quan-Feng Dong, Sheng-Xian Li, Han-Xi Yang

Journal of Electrochemistry

A number of polymer materials as candidates of host matrix of plastic polymer electrolyte were examined and techniques for preparation of thin_film electrolyte were reported. The results showed that the polymer electrolyte prepared with P(VDF_HFP) copolymer as host matrix and DBP as plasticizer exhibit the satisfactory mechanical strength and ionic conductivity. In comprison with liquid electrolyte systems, thin_film lithium ion battery has almost similar charge_discharge capacity and cycleability. The manufacture methods and the technical factors in making plasticizing lithium ion battery were also described in details.

The Influence Of Surface Diffusion Of Adsorbed Intermediate On Hydrogen Evolution Reaction At Pt/Nafion Composite Electrodes, Wei-Yi Tu, Lei Su, Wen-Jun Liu, Bing-Liang Wu

Journal of Electrochemistry

The decrease of over_potential of hydrogen evolution reaction at Pt black powder/Nafion microelectrode, comparing that of the Pt microdisk/Nafion electrode, was evident from the polarization curves of the Pt microdisk/Nafion electrode, platinized Pt micrdisk/Nafion electrode and Pt black powder/Nafion microelectrode. It is also evidenced by a plane Pt electrode with an additional free Pt surface. The surface diffusion and the surface recombination reaction of the adsorbed intermediate at the free surface of the Pt particles were supposed. It is an additional reaction path that induced the decrease of the concentration of the adsorbed intermediate. Thereby, the over_potential decreased.

An Investigation On The Corrosion Potential Imaging At The Interface Of Concrete/Reinforcing Bar In Corrosion Media, Rong-Zong Hu, Chang-Jian Lin, Xiang Zhou, Jian-Guang Tan, Xiong-Chao Zhao

Journal of Electrochemistry

The iron array electrode covered with concrete as a new electrochemical technique is applied to map the potential imaging and to investigate on the iron electrode corrosion process under concrete: In Cl - solution the corrosion of the iron array electrode covered with concrete had been prevented for a short term since the concrete protection, but the corrosion still occurreed and developed after immersed for a long time. In SO 4 2- solution although the sample had being immersed for a long time and the concrete was possibly broken, the corrosion did not develop. In Cl - solution the corrosion …

Electrochemical Codeposition Of Palladium And Glucose Oixdase In The Presence Of Glycine As Complexing Agent, Kan Zhu, Hui-Huang Wu

Journal of Electrochemistry

Glycine and Pd(NH 3) 2Cl 2 consist of a solution for the electrochemical codeposition of Pd and glucose oxidase (GOD) to prepare a metallized enzyme electrode. The experiments by UV/V spectroscopy show that the complexing of Pd ion with glycine can occur, which makes the plating bath has relatively stable chemical composition in a certain pH range. The voltammetric experiments indicate that the presense of glycine decreases the potential of Pd deposition ,facilitating to prevent the formation of palladium hydride. The appropriate conditions for the electrochemical codeposition of Pd and GOD are discussed.

Study Of The Cathod Of The Amperometric Glucose Sensor, Xiu-Juan Yu, Ding Zhou

Journal of Electrochemistry

The possibility for several kinds of conducting materials used as the cathode of glucose sensor was studied by the cathode polarization curves. It was shown that the titanium coated by RuO 2/TiO 2 is stable to the electrochemical corrosion and it could promote the generation of hydrogen. H 2O 2 could be detected in the electrochemical system constructed by the anode of graphite powder and epoxy resin composite and the cathode of titanium coated by RuO 2/TiO 2 in the potential range of 0.6V～0.8 V. It can be used as the cathode of glucose sensor instead of Pt. The response …

Effects Of Temperature On The Proton Diffusion Of Doped Ni(Oh)_2, Jian-Hua Liu, Jing-Wu Yang, Zhi-Yuan Tang

Journal of Electrochemistry

The Chronoamperometry of powder spherical Ni(OH) 2 microelectrode was used to study the proton diffusion coefficients of Ni(OH) 2. The proton diffusion coeefficients and the apparent diffusion active energy in anode and cathode processes at different temperature were obtained. Compared with pure Ni(OH) 2, the apparent diffusion active energy( E a) of Ni(OH) 2 doped with Co and Co+Zn was decreased and the diffusion constant( D o) was increased in the anode and the cathode processes, respectively, the effect of Co was greater. In contrast, for Ni(OH) 2 doped with Zn, its E a was increased and D o was …