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Articles 17521 - 17550 of 23770
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The Effects Of Dextromethorphan On Response Acquisition With Delayed Reinforcement, Thomas B. Morgan
The Effects Of Dextromethorphan On Response Acquisition With Delayed Reinforcement, Thomas B. Morgan
Dissertations
The current study examined in 2-h sessions the effects of intraperitoneal injections of dextromethorphan (DM) (0.0, 40.0, 60.0, and 80.0 mg/kg) on the acquisition of lever-press responding in rats that were exposed to a two-lever procedure in which responses on the reinforcement lever (RL) were reinforced with food after a 15-s resetting delay and responses on the cancellation lever cancelled a scheduled reinforcer. Response acquisition was observed at all drug doses. A decrease in RL responses, food deliveries, and the number of subjects that acquired responding was observed at the highest dose of DM. All doses of DM increased latency …
Acylpyrazolones: Synthesis, Self-Assembly And Lanthanide Metal Ion Separation, Jun Yang
Acylpyrazolones: Synthesis, Self-Assembly And Lanthanide Metal Ion Separation, Jun Yang
Dissertations
The central hypothesis that nanoscale self-assemblies can provide excellent metal ion recognition has been substantiated by employing acylpyrazolones and trivalent lanthanide metal ions as model systems. Several novel acylpyrazolones and their amphiphilic analogs have been designed, synthesized, and characterized. Their lanthanide metal ion recognition efficacies have been demonstrated through baseline separations of a mixture of light, middle, and heavy lanthanide metal ions by employing them in the aqueous mobile phase of high performance liquid chromatography (HPLC) with octadecylsilanized silica (ODS) as the stationary phase. The complex separation mechanism is influenced by the structures of acylpyrazolone and amphiphilic moieties, and spontaneous …
Optimization Of Sequential Purification Of Beta-Glucosidase From Tricoderma Reesei In Aqueous Two-Phase System, Shalini Gautam
Optimization Of Sequential Purification Of Beta-Glucosidase From Tricoderma Reesei In Aqueous Two-Phase System, Shalini Gautam
Dissertations
A novel sequential technique was developed for the purification of a valuable enzyme, beta-glucosidase, from microorganism Tricoderma reesei. The fungus T. reesei produces cellulose degrading enzymes, called cellulases: beta-glucosidase, endo-glucanase and exo-glucanase and low molecular weight proteins. For specific applications, the enzyme must be separated from other contaminants. The sequential technique, that included affinity precipitation with chitosan followed by separation with an aqueous two-phase system (ATPS), was implemented for the purification of beta-glucosidase from the culture filtrate of T. reesei.
The cultivation medium (nutrient) was optimized for the production of betaglucosidase from T. reesei cell culture. Treatment of the …
Nanostructured Composite Materials Based On Carbon Nanotubes And 3-D Photonic Crystals, Jing Chen
Nanostructured Composite Materials Based On Carbon Nanotubes And 3-D Photonic Crystals, Jing Chen
Dissertations
Carbon nanotubes (CNT) and in particular, single-wall carbon nanotubes (SWCNT) have been extensively studied, in large part, due to their unique one-dimensional crystalline structures and related electronic and optical properties. Various polymeric composite materials, which were based on carbon nanotubes, have been also developed in an attempt to combine the properties of polymer and CNT in a single film. Such composites were mainly formed by mixing carbon nanotubes within the polymer without special emphasis on the structure and thereby, the nanoscopic properties of the resultant material.
Photonic crystals belong to a class of man-made structures aimed at manipulating the propagation …
Communications Over Fading Channels With Partial Channel Information : Performance And Design Criteria, Xinmin Deng
Communications Over Fading Channels With Partial Channel Information : Performance And Design Criteria, Xinmin Deng
Dissertations
The effects of system parameters upon the performance are quantified under the assumption that some statistical information of the wireless fading channels is available. These results are useful in determining the optimal design of system parameters. Suboptimal receivers are designed for systems that are constrained in terms of implementation complexity.
The achievable rates are investigated for a wireless communication system when neither the transmitter nor the receiver has prior knowledge of the channel state information (CSI). Quantitative results are provided for independent and identically distributed (i.i.d.) Gaussian signals. A simple, low-duty-cycle signaling scheme is proposed to improve the information rates …
Development Of Adsorption Filtration Process For Virus Removal For Drinking Water Treatment, Vishal Vijay Gawarikar
Development Of Adsorption Filtration Process For Virus Removal For Drinking Water Treatment, Vishal Vijay Gawarikar
Dissertations
Recent monitoring studies have indicated that many ground water (GW) sources would benefit from the development of effective technologies for removing viruses. Although reverse osmosis can achieve high log removal it is not economical. The main objective of this study is to test and validate a novel adsorption filtration (AF) technology for removing viruses from GW sources for drinking water production in New Jersey.
The convective diffusion of viruses to adsorbent particle surfaces in flow packed beds (FPB) enhances their removal efficiency if the adsorbent particle size can be decreased to about 100 microns. The development of effective virus removal …
Modeling Of Flexible Drug-Like Molecules : Qsar Of Gbr 12909 Analog Dat/Sert Selectivity, Kathleen Mary Gilbert
Modeling Of Flexible Drug-Like Molecules : Qsar Of Gbr 12909 Analog Dat/Sert Selectivity, Kathleen Mary Gilbert
Dissertations
The dopamine reuptake inhibitor GBR 12909 and related dialkyl piperazine and piperidine analogs have been studied as agonist substitution therapies acting on the dopamine transporter (DAT) to treat cocaine addiction. Undesirable binding to the serotonin transporter (SERT) can vary greatly depending on the specific substituents on the molecule. This study uses Comparative Molecular Field Analysis (CoMFA) and Comparative Molecular Similarity Indices (CoMSIA) techniques to determine a stable and predictive model for DAT/SERT selectivity for a set of flexible GBR 12909 analogs.
Families of analogs were constructed from six pairs of naphthyl-substituted piperazine and piperidine templates identified by hierarchical clustering as …
Influences Of Surfactant On The Breakup Of A Fluid Jet In Viscous Surrounding, Muhammad Irfan Hameed
Influences Of Surfactant On The Breakup Of A Fluid Jet In Viscous Surrounding, Muhammad Irfan Hameed
Dissertations
The effect of insoluble surfactant on the breakup of a fluid jet surrounded by another viscous fluid at low Reynolds number is studied both theoretically and experimentally. Equations governing the evolution of the interface and surfactant concentration are derived using a long wavelength approximation for the case of an inviscid jet and a slightly viscous jet surrounded by a more viscous fluid. These one dimensional partial differential equations governing the evolution of the slender jet are solved numerically for given initial interfacial perturbations and surfactant concentration. It is found that the presence of insoluble surfactant at the interface retards the …
Mechanics Of Biocell Landfill Settlements, Chamil Hiroshan Hettiarachchi
Mechanics Of Biocell Landfill Settlements, Chamil Hiroshan Hettiarachchi
Dissertations
Prediction of landfill gas generation and settlements are of concerns in design and maintenance of biocell landfills. Accurate settlement prediction is essential for design of piping systems used for the delivery of re-circulated leachate and recovery of landfill gas. Landfill settlement is the result of change in overburden stresses and biodegradation of waste. Biodegradation-induced settlement results from the re-arrangement of waste skeleton in response to the decomposition of waste mass.
Current practice of landfill settlement modeling is predominantly empirical, thus most of the available techniques make no attempt to simulate the real mechanisms of waste settlement. Traditionally compressibility index is …
Evaporating Cross Flow Spray Jets In Gas-Solid Circulating Fluidized Bed, Tong Hoon Lee
Evaporating Cross Flow Spray Jets In Gas-Solid Circulating Fluidized Bed, Tong Hoon Lee
Dissertations
Three-phase flow of solid-gas suspension with liquid spray is found in many industrial applications, including fluidized catalytic cracking in petroleum refinery process, and wet scrubbing process. This dissertation study is aimed to understand the gas-solid-liquid three-phase flow structure, phase interactions and transport in a gas-solid circulating fluidized bed where an evaporating cross-flow liquid spray jet from a rectangular nozzle with a fan angle is injected. The investigation is based on both numerical and experimental approaches. The numerical study is for detailed field descriptions of the flow structure, phase interaction and distributions whereas the experimental study is for simulation validations. The …
Dynamics Of Filaments, Flares And Coronal Mass Ejections (Cmes), Ju Jing
Dynamics Of Filaments, Flares And Coronal Mass Ejections (Cmes), Ju Jing
Dissertations
The objective of this dissertation is to investigate the connection between the dynamics of solar surface phenomena such as filament eruptions, flares, the coronal mass ejections (CMEs), the core of so-called solar activity, and the properties of the associated magnetic field for the development of forecasts of solar activity and space weather. Both statistical and case studies have been carried out.
The topics covered in this dissertation are: the statistical relationship among phenomena of solar activity, in particular, filament eruptions, flares and coronal mass ejections (CMEs); the correlation between magnetic reconnection rate and flux rope acceleration of two-ribbon flares; the …
The Effects Of Digital Audio On Social Presence, Motivation And Perceived Learning In Asynchronous Learning Networks, Eunhee Kim
Dissertations
This study explores the possibilities of applying digital audio to the ALN environment, so that students can speak and listen rather than type and read. Two sets of 1x2 field experiments (text vs. digital audio) were conducted with two formats of digital audio -recorded voice messages and narrated Microsoft PowerPoint presentation - used in several NJIT courses conducted via ALN. The perceptions of communication media were measured from two different user perspectives: active use when the subjects created their assignments using prescribed communication media (audio or text) and passive use when the subjects viewed/listened to other students' work.
The perceptions …
Fluid-Phase Thermodynamics From Molecular-Level Properties And Interactions Based In Quantum Theory, Steven G. Arturo
Fluid-Phase Thermodynamics From Molecular-Level Properties And Interactions Based In Quantum Theory, Steven G. Arturo
Dissertations
A methodology to predict the thermodynamics of macroscopic fluid systems from quantum chemistry and statistical thermodynamics has been developed. This work extends the group-contribution concepts most utilized in chemical engineering. Computational chemistry software is used to define the geometries and electron density profiles of target molecules. Atoms in Molecules theory and associated software packages are used to calculate rigorous properties of the functional groups within molecules of interest. These properties are incorporated into an intermolecular potential energy function which describes interactions between entire molecules as a set of interactions between functional groups. This information is applied to a lattice-fluid model …
Some Topics On Deterministic Scheduling Problems, Yumei Huo
Some Topics On Deterministic Scheduling Problems, Yumei Huo
Dissertations
Sequencing and scheduling problems are motivated by allocation of limited resources over time. The goal is to find an optimal allocation where optimality is defined by some problem specific objectives.
This dissertation considers the scheduling of a set of ri tasks, with precedence constraints, on m >= 1 identical and parallel processors so as to minimize the makespan. Specifically, it considers the situation where tasks, along with their precedence constraints, are released at different times, and the scheduler has to make scheduling decisions without knowledge of future releases. Both preemptive and nonpreemptive schedules are considered. This dissertation shows that optimal …
Direct Numerical Simulations And Experimental Investigation Of Dielectrophoresis, Arun Thankamony John-Kadaksham
Direct Numerical Simulations And Experimental Investigation Of Dielectrophoresis, Arun Thankamony John-Kadaksham
Dissertations
This dissertation deals with the numerical and experimental studies of the phenomenon of dielectrophoresis, i.e., the motion of neutral particles in nonuniform electric fields. Dielectrophoresis is the translatory motion of neutral particles suspended in a dielectric medium when they are subjected to an external nonuniform electric field. The translatory motion occurs because a force called the dielectrophoretic force, which depends on the spatial variation of the electric field, acts on the particles. As the generation of force involves no moving parts and the particles can be moved without touching them, dielectrophoresis can be used in many applications, including manipulation and …
Analysis And Characterization Of The Integrated Dielectric Slab Waveguide-Wedge Antenna Using Iterative Mode-Matching Technique, Chairat Pinthong
Analysis And Characterization Of The Integrated Dielectric Slab Waveguide-Wedge Antenna Using Iterative Mode-Matching Technique, Chairat Pinthong
Dissertations
A rigorous solution for the TB and TM polarization to the dielectric wedge antenna fed by a slab waveguide of the same material is presented. The method of solution involves modeling the wedge as a sequence of step discontinuities and using an iterative procedure to track forward and backward partial wave fields, expressed as modal expansions, to obtain the rigorous field solution. Radiation patterns of directive gain are presented. All patterns smoothly decrease from a maximum in the endfire direction and exhibit very low side lobes. Longer length wedges are shown to produce higher directivity and smaller half-power beamwidths (HPBW). …
Evaluating Rhizodegradation Of Petroleum Hydrocarbons And Polycyclic Aromatic Hydrocarbons In Wetland Sediments Containing Spartina Patens, Robert J. Lippencott
Evaluating Rhizodegradation Of Petroleum Hydrocarbons And Polycyclic Aromatic Hydrocarbons In Wetland Sediments Containing Spartina Patens, Robert J. Lippencott
Dissertations
Biodegradation of petroleum hydrocarbons (PHC) and 16 polycyclic aromatic hydrocarbon (PAH) compounds was evaluated in sediments from a stormwater basin that was a former salt marsh at an active oil refinery. Spartina patens were grown in basin sediments during a field study and a greenhouse study over three consecutive growing seasons. Ninety percent (90%) survival was observed in field study plots containing sediments with <12% PHC. In the greenhouse study, planted and bulk sediments were monitored for PHC, PAH, microbial density, nutrients, pH, redox and root biomass at 2.5 and 7.5 cm in sediments with <12% PHC. The sediments contained on average 6.5% to 9.5% PHC and 56 to 124 parts per million (ppm) total PAH. The plants exhibited a 95% survival rate and added from 1% to 2% root biomass to the sediment. Microbial densities in planted sediments were significantly higher than in bulk sediments (p<0.05). Oxidizing conditions were prevalent in all treatments at both depths; however, reducing conditions developed in the planted sediments at 7.5 cm. PHC was 35% to 37% lower in the planted sediments vs. bulk sediment at the end of the study. Planted sediment PAH concentrations were generally lower than in bulk sediments. Low MW PAHs (2 and 3-Rings) were either absent or at relatively low concentrations in all treatments. Phenanthrene concentrations in bulk sediments did not change, but were reduced by 95% in planted sediments (p<0.01), with half-life estimates of 141 to 165 days at 2.5 cm. Temporal changes in high MW PAHs ( 4-Rings) were not observed over the greenhouse study period. Differences in PAH concentrations between planted and bulk sediments exhibited a decreasing trend with PAH molecular weight. Evaluation of differences in planted and bulk sediment PAH concentrations suggests that lower MW PAHs degrade better under oxidizing conditions, and higher MW PAHs under reducing conditions in the planted sediments. Comparison of planted and bulk sediment PAH concentrations links depth and redox conditions to decreases in PAH as a function of PAH MW. Therefore, it was concluded that spatio-temporal variations and cycling of redox conditions should be considered to properly evaluate biodegradation of PAH.
Theory And Algorithms For Swept Manifold Intersections, Yuriy Mileyko
Theory And Algorithms For Swept Manifold Intersections, Yuriy Mileyko
Dissertations
Recent developments in such fields as computer aided geometric design, geometric modeling, and computational topology have generated a spate of interest towards geometric objects called swept volumes. Besides their great applicability in various practical areas, the mere geometry and topology of these entities make them a perfect testbed for novel approaches aimed at analyzing and representing geometric objects. The structure of swept volumes reveals that it is also important to focus on a little simpler, although a very similar type of objects - swept manifolds. In particular, effective computability of swept manifold intersections is of major concern.
The main goal …
Virtual Transshipments And Revenue-Sharing Contracts In Supply Chain Management, Zhaoqiong Qin
Virtual Transshipments And Revenue-Sharing Contracts In Supply Chain Management, Zhaoqiong Qin
Dissertations
This dissertation presents the use of virtual transshipments and revenue-sharing contracts for inventory control in a small scale supply chain. The main objective is to maximize the total profit in a centralized supply chain or maximize the supply chain's profit while keeping the individual components' incentives in a decentralized supply chain.
First, a centralized supply chain with two capacitated manufacturing plants situated in two distinct geographical regions is considered. Normally, demand in each region is mostly satisfied by the local plant. However, if the local plant is understocked while the remote one is overstocked, some of the newly generated demand …
Simulation Of Creep In Nickel Based Single Crystal Superalloys, Yunhong Pang
Simulation Of Creep In Nickel Based Single Crystal Superalloys, Yunhong Pang
Dissertations
Nickel based single crystal Superalloys are finding wide spread use in high temperature gas turbines and other similar applications because of their superior high-temperature strength and creep properties as compared to the other materials. This is due to two factors: solid solution and precipitation strengthening of the gamma (γ) and gamma prime (γ') phases, and the elimination of grain boundaries. Creep of Nickel based single crystal Superalloys are caused by two primary mechanisms, dislocation creep and diffusion creep. Several factors that affect the creep life of Nickel based single crystal Superalloys are the specific microstructure, stress, temperature and rafting. Also, …
Security Information Management With Frame-Based Attack Presentation And First-Order Reasoning, Wei Yan
Security Information Management With Frame-Based Attack Presentation And First-Order Reasoning, Wei Yan
Dissertations
Internet has grown by several orders of magnitude in recent years, and this growth has escalated the importance of computer security. Intrusion Detection System (IDS) is used to protect computer networks. However, the overwhelming flow of log data generated by IDS hamper security administrators from uncovering new insights and hidden attack scenarios. Security Information Management (SIM) is a new growing area of interest for intrusion detection. The research work in this dissertation explores the semantics of attack behaviors and designs Frame-based Attack Representation and First-order logic Automatic Reasoning (FAR-FAR) using linguistics and First-order Logic (FOL) based approaches. Techniques based on …
Transceiver Design And System Optimization For Ultra-Wideband Communications, Hongshan Sheng
Transceiver Design And System Optimization For Ultra-Wideband Communications, Hongshan Sheng
Dissertations
This dissertation investigates the potential promises and proposes possible solutions to the challenges of designing transceivers and optimizing system parameters in ultra-wideband (UWB) systems. The goal is to provide guidelines for UWB transceiver implementations under constraints by regulation, existing interference, and channel estimation.
New UWB pulse shapes are invented that satisfy the Federal Communications Commission spectral mask. Parameters are designed to possibly implement the proposed pulses. A link budget is quantified based on an accurate frequency-dependent path loss calculation to account for variations across the ultra-wide bandwidth of the signal.
Achievable information rates are quantified as a function of transmission …
Quality-Of-Service Provisioning In High Speed Networks : Routing Perspectives, Gang Cheng
Quality-Of-Service Provisioning In High Speed Networks : Routing Perspectives, Gang Cheng
Dissertations
The continuous growth in both commercial and public network traffic with various quality-of-service (QoS) requirements is calling for better service than the current Internet's best effort mechanism. One of the challenging issues is to select feasible paths that satisfy the different requirements of various applications. This problem is known as QoS routing. In general, two issues are related to QoS routing: state distribution and routing strategy. Routing strategy is used to find a feasible path that meets the QoS requirements. State distribution addresses the issue of exchanging the state information throughout the network, and can be further divided into two …
Scheduling Policies For Disks And Disk Arrays, Chang Liu
Scheduling Policies For Disks And Disk Arrays, Chang Liu
Dissertations
Recent rapid advances of magnetic recording technology have enabled substantial increases in disk capacity. There has been less than 10% improvement annually in the random access time to small data blocks on the disk. Such accesses are very common in OLTP applications, which tend to have stringent response time requirements. Scheduling of disk requests is intended to improve their response time, reduce disk service time, and increase disk access bandwidth with respect to the default FCFS scheduling policy.
Shortest Access Time First policy has been shown to outperform other classical disk scheduling policies in numerous studies. Before verifying this conclusion, …
Image Watermarking, Steganography, And Morphological Processing, Yi-Ta Wu
Image Watermarking, Steganography, And Morphological Processing, Yi-Ta Wu
Dissertations
With the fast development of computer technology, research in the fields of multimedia security, image processing, and robot vision have recently become popular. Image watermarking, steganogrphic system, morphological processing and shortest path planning are important subjects among them. In this dissertation, the fundamental techniques are reviewed first followed by the presentation of novel algorithms and theorems for these three subjects.
The research on multimedia security consists of two parts, image watermarking and steganographic system. In image watermarking, several algorithms are developed to achieve different goals as shown below. In order to embed more watermarks and to minimize distortion of watermarked …
Collaborative Examinations In Asyncronous Learning Networks : Field Experiments On Collaborative Learning Through Online Assessments, Jia Shen
Dissertations
With the proliferation of computer networks and the emergence of virtual teams, learning and knowledge sharing in the online environment has become an increasingly important topic. Applying constructivism and collaborative learning theories to assessment, the collaborative online exam is designed featuring students' active participation in various phases of the exam process through small group activities online. A participatory online exam process is designed featuring similar procedures except that students' involvement in each phase of the exam is individual. The collaborative online exam and the participatory online exam are investigated regarding student exam study strategies, group process, exam outcomes, faculty satisfaction, …
Bioinformatics Study Of Mammalian Mrna Polydenylation, Haibo Zhang
Bioinformatics Study Of Mammalian Mrna Polydenylation, Haibo Zhang
Dissertations
Messenger RNA polyadenylation is one of the key post-transcriptional events in mammalian cells, which have influences on many aspects of mRNA metabolism. Several human diseases have been shown to associate with abnormal polyadenylation, highlighting the importance of this process. The availability of the complete sequence of human and mouse genomes, together with their gene expression data provides valuable resources to study mRNA polyadenylation on a system level. This dissertation addresses the following issues of mammalian mRNA polyadenylation through bioinformatics approaches: (1) the extensive documentation of several key aspects of polyadenylation sites in humans and mice on a genomic level; (2) …
Gas Fluidization Of Nanoparticles, Qun Yu
Gas Fluidization Of Nanoparticles, Qun Yu
Dissertations
The primary objective of this study is to perform a systematic investigation on the gas fluidization of various nanoparticle agglomerates. Firstly, the gas fluidization characteristics and regime classifications without any additional external force fields are identified using both experimental measurements and modeling. Secondly, the effect of introducing certain external force fields on nanoparticle fluidization is experimentally investigated. Two external force fields were applied: sound waves from a loud speaker (acoustic assistance) and in-bed magnets that were excited by an external oscillating magnetic field (magnetic assistance). Thirdly, exploratory experimental research on the use of nanoparticle agglomerates as a granular filtration media …
Electromagnetic And Acoustic Propagation In Strip Lines And Porous Media, Lin Zhou
Electromagnetic And Acoustic Propagation In Strip Lines And Porous Media, Lin Zhou
Dissertations
Wave propagation in two physical structures is described and analyzed in this dissertation. In the first problem, the propagation of a normally incident plane acoustic wave through a three dimensional rigid slab with periodically placed holes is modeled and analyzed. The spacing of the holes A and B, the wavelength λ and the thickness of the slab L are order one parameters compared to the characteristic size D of the holes, which is a small quantity. Scattering matrix techniques are used to derive expressions for the transmission and reflection coefficients of the lowest mode. These expressions depend only on the …
On Rate Capacity And Signature Sequence Adaptation In Downlink Of Mc-Cdma System, Jianming Zhu
On Rate Capacity And Signature Sequence Adaptation In Downlink Of Mc-Cdma System, Jianming Zhu
Dissertations
This dissertation addresses two topics in the MC-CDMA system: rate capacity and adaptation of users' signature sequences. Both of them are studied for the downlink communication scenario with multi-code scheme.
The purpose of studying rate capacity is to understand the potential of applying MC-CDMA technique for high speed wireless data communications. It is shown that, to maintain high speed data transmission with multi-code scheme, each mobile should cooperatively decode its desired user's encoded data symbols which are spread with different signature sequences simultaneously. Higher data rate can be achieved by implementing dirty paper coding (DPC) to cooperatively encode all users' …