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2006

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Articles 4501 - 4530 of 5872

Full-Text Articles in Physical Sciences and Mathematics

Classifying Quadratic Number Fields Up To Arf Equivalence, Jeonghun Kim Jan 2006

Classifying Quadratic Number Fields Up To Arf Equivalence, Jeonghun Kim

LSU Doctoral Dissertations

Two number fields K and L are said to be Arf equivalent if there exists a bijection T : ­ΩK → Ω­L of places of K and of L such that KP and LTP are locally Arf equivalent for every place P ε ΩK. That is, |K*p/K*2p| = |L*TP/L*2TP|, type[( , )P] = type[( , )TP], and Arf(rP ) = Arf(rTP ) for every place P ε ΩK, where rP is the local …

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Investigation Into The Dirhodium-Catalyzed Hydroformylation Of 1-Alkenes And Preparation Of A Novel Tetraphosphine Ligand, Alexandre R. Monteil Jan 2006

Investigation Into The Dirhodium-Catalyzed Hydroformylation Of 1-Alkenes And Preparation Of A Novel Tetraphosphine Ligand, Alexandre R. Monteil

LSU Doctoral Dissertations

The reaction of the tetraphosphine ligand rac-et,ph-P4 (et,ph-P4 = PEt2CH2CH2(Ph)PCH2P(Ph)CH2CH2PEt2) with 2 equiv. of [Rh(nbd)2]+ (nbd = norbornadiene) generates [rac-Rh2(nbd)2(et,ph-P4)]2+, which is the precursor to a highly active and regioselective hydroformylation catalyst system. The “key” catalyst species generated under H2/CO pressure has been proposed to be the dihydrido complex [rac-Rh2H2(ì-CO)2(et,ph-P4)]2+, and represents one of the most dramatic example of homobimetallic …

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Spatial Distribution Of Anthropogenic Environmental Hazards In The Louisiana Coastal Zone: Implications For Ecosystem Restoration, Melissa Ann Kroninger Jan 2006

Spatial Distribution Of Anthropogenic Environmental Hazards In The Louisiana Coastal Zone: Implications For Ecosystem Restoration, Melissa Ann Kroninger

LSU Master's Theses

The purpose of this project was to assess the spatial distribution of anthropogenic environmental hazards in the Louisiana coastal zone and implications of those hazards for coastal resources and restoration efforts. Several state and federal environmental databases publicly available on the internet were selected for inclusion in this study. The hazard sites were mapped in a Geographic Information System by geocoding addresses obtained from the databases. Sites with unmatched addresses were mapped to zip code centroid. Hazard types in databases lacking spatial data at the address level were totaled and mapped by parish. Buffers were created at 1, 2, 3, …

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Impacts Of Red Imported Fire Ants (Solenopsis Invicta Buren) On Native Faunal Communities In Two Pine-Dominated Forests, Lee A. Womack Jan 2006

Impacts Of Red Imported Fire Ants (Solenopsis Invicta Buren) On Native Faunal Communities In Two Pine-Dominated Forests, Lee A. Womack

LSU Master's Theses

Impacts red imported fire ants (RIFA) exert on native faunal communities were monitored in two pine-dominated ecosystems in Louisiana. After suppression of established RIFA populations with Amdro®, cotton mice (Peromyscus gossypinus), herpetofaunal, ground-dwelling invertebrate, Lycosidae, and non-target ant communities were compared between untreated-control and treated plots with respect to possible ecological impacts of RIFA on these communities. Efficacy of Amdro® (A. I. 0.7% hydramethylnon) was tested at Alexander State Forest and Sandy Hollow WMA, and was found to be effective at both sites for 99-42.3% and 97-48%, respectively, suppression of RIFA on treated plots, for three to seven months, with …

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Neuro Control Of Nonlinear Discrete Time Systems With Deadzone And Input Constraints, Pingan He, Wenzhi Gao, Jagannathan Sarangapani Jan 2006

Neuro Control Of Nonlinear Discrete Time Systems With Deadzone And Input Constraints, Pingan He, Wenzhi Gao, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

A neural network (NN) controller in discrete time is designed to deliver a desired tracking performance for a class of uncertain nonlinear systems with unknown deadzones and magnitude constraints on the input. The NN controller consists of two NNs: the first NN for compensating the unknown deadzones; and the second NN for compensating the uncertain nonlinear system dynamics. The magnitude constraints on the input are modeled as saturation nonlinearities and they are dealt with in the Lyapunov-based controller design. The uniformly ultimate boundedness (UUB) of the closed-loop tracking errors and the neural network weights estimation errors is demonstrated via Lyapunov …

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Adaptive Distributed Fair Scheduling And Its Implementation In Wireless Sensor Networks, Maciej Jan Zawodniok, Jagannathan Sarangapani, Steve Eugene Watkins, James W. Fonda Jan 2006

Adaptive Distributed Fair Scheduling And Its Implementation In Wireless Sensor Networks, Maciej Jan Zawodniok, Jagannathan Sarangapani, Steve Eugene Watkins, James W. Fonda

Electrical and Computer Engineering Faculty Research & Creative Works

A novel adaptive and distributed fair scheduling (ADFS) scheme for wireless sensor networks is shown through hardware implementation. In contrast to simulation, hardware evaluation provides valuable feedback to protocol and hardware development process. The proposed protocol focuses on quality-of-service (QoS) issues to address flow prioritization. Thus, when nodes access a shared channel, the proposed ADFS allocates the channel bandwidth proportionally to the weight, or priority, of the packet flows. Moreover, ADFS allows for dynamic allocation of network resources with little added overhead. Weights are initially assigned using user specified QoS criteria. These weights are subsequently updated as a function of …

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Decentralized Power Control With Implementation For Rfid Networks, Kainan Cha, Anil Ramachandran, David Pommerenke, Jagannathan Sarangapani Jan 2006

Decentralized Power Control With Implementation For Rfid Networks, Kainan Cha, Anil Ramachandran, David Pommerenke, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

In radio frequency identification (RFID) systems, the detection range and read rates will suffer from interference among high power reading devices. This problem grows severely and degrades system performance in dense RFID networks. In this paper, we investigate a suite of feasible power control schemes to ensure overall coverage area of the system while maintaining a desired read rate. The power control scheme and MAC protocol dynamically adjusts the RFID reader power output in response to the interference level seen locally during tag reading for an acceptable signal-to-noise ratio (SNR). We present novel distributed adaptive power control (DAPC) and probabilistic …

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Development And Implementation Of Optimized Energy-Delay Sub-Network Routing Protocol For Wireless Sensor Networks, Maciej Jan Zawodniok, Jagannathan Sarangapani, Steve Eugene Watkins, James W. Fonda Jan 2006

Development And Implementation Of Optimized Energy-Delay Sub-Network Routing Protocol For Wireless Sensor Networks, Maciej Jan Zawodniok, Jagannathan Sarangapani, Steve Eugene Watkins, James W. Fonda

Electrical and Computer Engineering Faculty Research & Creative Works

The development and implementation of the optimized energy-delay sub-network routing (OEDSR) protocol for wireless sensor networks (WSN) is presented. This ondemand routing protocol minimizes a novel link cost factor which is defined using available energy, end-to-end (E2E) delay and distance from a node to the base station (BS), along with clustering, to effectively route information to the BS. Initially, the nodes are either in idle or sleep mode, but once an event is detected, the nodes near the event become active and start forming sub-networks. Formation of the inactive network into a sub-network saves energy because only a portion of …

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Distributed Power Control For Cellular Networks In The Presence Of Channel Uncertainties, Maciej Jan Zawodniok, Q. Shang, Jagannathan Sarangapani Jan 2006

Distributed Power Control For Cellular Networks In The Presence Of Channel Uncertainties, Maciej Jan Zawodniok, Q. Shang, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a novel distributed power control (DPC) scheme for cellular network in the presence of radio channel uncertainties such as path loss, shadowing, and Rayleigh fading is presented. Since these uncertainties can attenuate the received signal strength and can cause variations in the received Signal-to-Interference ratio (SIR), a new DPC scheme, which can estimate the slowly varying channel uncertainty, is proposed so that a target SIR at the receiver can be maintained. Further, the standard assumption of a constant interference during a link's power update used in other works in the literature is relaxed. A CDMA-based cellular network …

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Adaptive And Probabilistic Power Control Algorithms For Dense Rfid Reader Network, Kainan Cha, Anil Ramachandran, Jagannathan Sarangapani Jan 2006

Adaptive And Probabilistic Power Control Algorithms For Dense Rfid Reader Network, Kainan Cha, Anil Ramachandran, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

In radio frequency identification (RFID) systems, the detection range and read rates may suffer from interferences between high power devices such as readers. In dense networks, this problem grows severely and degrades system performance. In this paper, we investigate feasible power control schemes to ensure overall coverage area of the system while maintaining a desired data rate. The power control should dynamically adjust the output power of a RFID reader by adapting to the noise level seen during tag reading and acceptable signal-to-noise ratio (SNR). We present a novel distributed adaptive power control (DAPC) and probabilistic power control (PPC) as …

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A Community Approach To Identifying Essential Fish Habitat Of Spotted Seatrout, Cynoscion Nebulosus, In Barataria Bay, La, Pamela Sharon Dawn Macrae Jan 2006

A Community Approach To Identifying Essential Fish Habitat Of Spotted Seatrout, Cynoscion Nebulosus, In Barataria Bay, La, Pamela Sharon Dawn Macrae

LSU Doctoral Dissertations

Louisiana wetlands are disappearing at a dramatic rate, providing an impetus for identifying essential fish habitat (EFH) in this region. The distribution, relative abundance, biomass, length and food web dynamics of spotted seatrout, Cynoscion nebulosus, as well as the fish assemblage structure were examined in Barataria Bay, LA, in relation to habitat type and physical/chemical properties of the water. All fish were collected from three sites located along a salinity gradient, each contained the three habitat types of interest: marsh edge, soft bottom and oyster shell, and were sampled monthly from May 2003 to May 2004 with gillnets. Habitat preference …

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An Architecture For Adaptive Real Time Communication With Embedded Devices, Amol S. Patwardhan Jan 2006

An Architecture For Adaptive Real Time Communication With Embedded Devices, Amol S. Patwardhan

LSU Master's Theses

The virtual testbed is designed to be a cost-effective rapid development environment as well as a teaching tool for embedded systems. Teaching and development of embedded systems otherwise requires dedicated real time operating systems and costly infrastructure for hardware simulation. Writing control software for embedded systems with such a setup takes prolonged development cycles. Moreover, actual hardware may get damaged while writing the control software. On the contrary, in a virtual testbed environment, a simulator running on the host machine is used instead of the actual hardware, which then interacts with an embedded processor through serial communication. This hardware-in-the-loop setup …

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Tomotherapy For Post-Mastectomy Radiotherapy (Pmrt): Comparison With Conventional Electron Beam Technique, Michael Sissay Ashenafi Jan 2006

Tomotherapy For Post-Mastectomy Radiotherapy (Pmrt): Comparison With Conventional Electron Beam Technique, Michael Sissay Ashenafi

LSU Master's Theses

Purpose: TomoTherapy, capable of delivering intensity-modulated, image-guided radiotherapy with a helical fan-beam, multileaf-collimated beam and detector array mounted on a CT ring, is challenging the treatment techniques commonly used in today's radiotherapy clinic. The present works investigates the potential of using TomoTherapy in lieu of electron beams for treatment of the chest wall in post-mastectomy radiotherapy (PMRT). It is hypothesized that TomoTherapy can plan dose distributions for PMRT patients, that a pre-selected radiation oncologist judges to be equal to or better than that of a conventional plan treated with electron beams. Methods: A patient database of retrospective conventional PMRT treatment …

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Circuits And Structure In Matroids And Graphs, Brian Daniel Beavers Jan 2006

Circuits And Structure In Matroids And Graphs, Brian Daniel Beavers

LSU Doctoral Dissertations

This dissertation consists of several results on matroid and graph structure and is organized into three main parts. The main goal of the first part, Chapters 1-3, is to produce a unique decomposition of 3-connected matroids into more highly connected pieces. In Chapter 1, we review the definitions and main results from the previous work of Hall, Oxley, Semple, and Whittle. In Chapter 2, we introduce operations that allow us to decompose a 3-connected matroid M into a pair of 3-connected pieces by breaking the matroid apart at a 3-separation. We also generalize a result of Akkari and Oxley. In …

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Caliche As A Geologic Repository For Atmospheric Sulfate, Katie Jane Howell Jan 2006

Caliche As A Geologic Repository For Atmospheric Sulfate, Katie Jane Howell

LSU Master's Theses

Recent studies demonstrate that important information on sulfur source, oxidation pathway, transport pattern, and reaction kinetics of the oxidation reactions of reduced sulfur gases in the atmosphere may be uncovered by measuring multiple sulfur and oxygen isotope compositions of the oxidation product — secondary atmospheric sulfate (SAS). SAS from Earth’s distant past, however, is rarely preserved in the rock record because of its high solubility and small quantity. Caliche, a pedogenic carbonate formed in arid to semi-arid continental settings and common in the geologic record, could serve as a repository for ancient SAS. Two major groups of caliche samples: 1) …

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Investigation Of The Structure In Electrodeposited Nanostructured Co/Cu Alloys, Multilayers, And Cofe/Cu Multilayered Nanowires, Erick Jamal Lawson Jan 2006

Investigation Of The Structure In Electrodeposited Nanostructured Co/Cu Alloys, Multilayers, And Cofe/Cu Multilayered Nanowires, Erick Jamal Lawson

LSU Master's Theses

Since the discovery of giant magnetoresistance (GMR) in electrodeposited nanostructured magnetic multilayers and multilayered nanowires, there has been interest throughout the scientific world in the fabrication and characterization of these materials. Magnetic multilayers in the form of thin films can be used as magnetoresistive sensors in the magnetic data storage industry. Arrays of nanowires have the potential for applications in perpendicular ultra-high density data storage and biosensors. Wire-shaped magnetic multilayered nanowires have been shown to exhibit GMR in the so called “current perpendicular-to plane” configuration (CPP-GMR). GMR of multilayers and multilayered nanowires have been investigated in several systems that include …

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Application Of Short-Term Sediment Dynamics And Particle-Bound Phosphorus Fractionation Methods (Sedex) To Estimate The Benthic Nutrient Loading Potential In Upper Newport Estuary, California, Hilary Amanda Collis Jan 2006

Application Of Short-Term Sediment Dynamics And Particle-Bound Phosphorus Fractionation Methods (Sedex) To Estimate The Benthic Nutrient Loading Potential In Upper Newport Estuary, California, Hilary Amanda Collis

LSU Master's Theses

Estuaries act as sources, sinks, and biogeochemical transformation sites for natural and anthropogenically-derived nutrients. Sediment loading from watersheds provides an important source of particulate nutrients to estuaries often neglected when constructing nutrient budgets. Deposition and resuspension of these sediments are known to impact biogeochemical cycles in estuarine environments. Phosphorus (P) exists in many forms in aquatic environments, and increased P loading to coastal environments increases primary productivity potentially leading to eutrophication. Magnitude and variability of sediment deposition, resuspension, and sediment-bound P concentrations were evaluated in Upper Newport Bay (UNB), California. During 2004, seven push cores were collected from the intertidal …

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Effects Of Fire On Habitat Associations, Abundance, And Survival Of Wintering Henslow's Sparrows (Ammodramus Henslowii) In Southeastern Louisiana Longleaf Pine Savannas, Erik Ivan Johnson Jan 2006

Effects Of Fire On Habitat Associations, Abundance, And Survival Of Wintering Henslow's Sparrows (Ammodramus Henslowii) In Southeastern Louisiana Longleaf Pine Savannas, Erik Ivan Johnson

LSU Master's Theses

The Henslow’s Sparrow (Ammodramus henslowii) is the fastest declining short-distance migrant and fastest declining grassland bird in North America. Declines in longleaf pine (Pinus palustris) savannas, its primary wintering habitat, have exceeded 97%. Other than basic habitat requirements, very little is known about its wintering ecology. I examined habitat associations of wintering Henslow’s Sparrows resulting from fire in longleaf pine savannas in southeastern Louisiana during two winters. Because it is important to understand the relative importance of habitat parameters, which include structure, species composition, and food availability, I measured these to determine their relative importance to Henslow’s Sparrow densities. I …

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Using Life-History, Surplus Production, And Individual-Based Population Models For Stock Assessment Of Data-Poor Stocks: An Application To Small Pelagic Fisheries Of The Lingayen Gulf, Philippines, Ronald B. Lachica Jan 2006

Using Life-History, Surplus Production, And Individual-Based Population Models For Stock Assessment Of Data-Poor Stocks: An Application To Small Pelagic Fisheries Of The Lingayen Gulf, Philippines, Ronald B. Lachica

LSU Master's Theses

Stock assessment methods that quantify the status of fishery resources are critical to effective fisheries management. There is a need for stock assessment methods applicable for management of tropical species based on limited, un-aged catch data. I applied four stock assessment approaches to situation with limited life-history information and with short-term, un-aged catch data. The four approaches are: life-history invariants, length-based catch analysis, individual-based modeling, and surplus production modeling. All four approaches were applied to catch data from Lingayen Gulf, Philippines. The life-history invariant, length-based catch analysis, and individual-based modeling were applied to monthly length-frequency data of commercial catch for …

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High Harmonic Generation By Short Laser Pulses: Time-Frequency Behavior And Applications To Attophysics, Mitsuko Murakami Jan 2006

High Harmonic Generation By Short Laser Pulses: Time-Frequency Behavior And Applications To Attophysics, Mitsuko Murakami

LSU Doctoral Dissertations

High harmonic generation (HHG) is a process in which noble gas atoms excited by an intense laser field at frequency ω1 emit radiation of higher frequencies that are odd integer multiples of ω1. Driven by an infrared laser, high harmonic radiation can span from the optical into the extreme ultraviolet (XUV) frequency range. In this thesis, I study HHG using short laser pulses by solving the time-dependent Schrödinger equation (TDSE). In particular, I will focus on calculating and controlling the time-dependent instantaneous frequency (chirp) of high harmonics. The harmonic chirp is a direct consequence of the atom-field …

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Use Of Atomic Force Microscopy To Study A Molecular Micelle As An Anionic Polymer For Polyelectrolyte Multilayer Deposition On Polymeric Substrates, Angela Nakeeta Douglas Jan 2006

Use Of Atomic Force Microscopy To Study A Molecular Micelle As An Anionic Polymer For Polyelectrolyte Multilayer Deposition On Polymeric Substrates, Angela Nakeeta Douglas

LSU Master's Theses

Polyelectrolyte multilayers (PEMs) have been used as stationary phases for various chiral and achiral separations in open-tubular electrochromatagraphy (OT-CEC). However, the physical characteristics of PEMs are not well understood. The production of PEM coatings involves flowing alternating rinses of positive and negative charged polyelectrolytes onto a surface. Although PEMs are typically deposited on fused silica capillaries, there is growing interest to use this approach in conjunction with microchip devices to enhance separation characteristics. Since microchips are fabricated using polymeric substrates, the deposition of PEMs on these substrates needs to be examined. The study reported in this thesis uses atomic force …

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Optimal Binary Trees With Height Restrictions On Left And Right Branches, Song Ding Jan 2006

Optimal Binary Trees With Height Restrictions On Left And Right Branches, Song Ding

LSU Master's Theses

We begin with background definitions on binary trees. Then we review known algorithms for finding optimal binary search trees. Knuth's famous algorithm, presented in the second chapter, is the cornerstone for our work. It depends on two important results: the Quadrangle Lemma and the Monoticity Theorem. These enabled Knuth to achieve a time complexity of O(n2), while previous algorithms had been O(n3) (n = size of input). We present the known generalization of Knuth's algorithm to trees with a height restriction. Finally, we consider the previously unexamined case of trees with different restrictions on left and …

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Winter Diet, Seed Preferences And Foraging Behavior Of Henslow's Sparrows (Ammodramus Henslowii) In Southeastern Louisiana, Jennifer K. Dimiceli Jan 2006

Winter Diet, Seed Preferences And Foraging Behavior Of Henslow's Sparrows (Ammodramus Henslowii) In Southeastern Louisiana, Jennifer K. Dimiceli

LSU Master's Theses

Henslow's Sparrow (Ammodramus henslowii) is a grassland bird whose population is declining throughout its range, mainly due to habitat loss. The Longleaf Pine forest ecosystems in which Henslow's Sparrows spend their winters are reduced to 5% of their former range. The winter ecology of Henslow's Sparrow remains understudied, especially regarding important aspects of diet and foraging behavior. To determine winter diet, I collected fecal samples from Henslow's Sparrows during banding operations in southeastern Louisiana pine savannas from October 2003-March 2004 and October 2004-April 2005. I then analyzed the samples for presence of seeds and arthropod parts, identified them to the …

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Secrout: A Secure Routing Protocol For Sensor Networks, Jian Yin, Sanjay Kumar Madria Jan 2006

Secrout: A Secure Routing Protocol For Sensor Networks, Jian Yin, Sanjay Kumar Madria

Computer Science Faculty Research & Creative Works

In this paper, we present a secure routing protocol for sensor networks (SecRout) to safeguard sensor networks under different types of attacks. The SecRout protocol uses the symmetric cryptography to secure messages, and uses a small cache in sensor nodes to record the partial routing path (previous and next nodes) to the destination. It guarantees that the destination will be able to identify and discard the tampered messages and ensure that the messages received are not tampered. Comparing the performance with non-secure routing protocol AODV (ad hoc on demand distance vector routing), the SecRout protocol only has a small byte …

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Window Query Processing With Proxy Cache, Gao Xing, John Sustersic, A. R. Hurson Jan 2006

Window Query Processing With Proxy Cache, Gao Xing, John Sustersic, A. R. Hurson

Computer Science Faculty Research & Creative Works

A location dependent query (LDQ) result set is valid only in a specific region called the validity region (VR). While limiting the validity of a particular result set to a given area, the VR may also be used in caching implementations to determine if cached results satisfy semantically equivalent queries. Existing LDQ caching schemes rely on the database servers to provide the VR at a cost of high computational overhead. Alternatively, a LDQ proxy cache, which approximates the VR can be employed, freeing the database servers from the high cost of calculating the VR. A LDQ proxy cache architecture is …

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Multimedia Correlation Analysis In Unstructured Peer-To-Peer Network, Bo Yang, A. R. Hurson, Yu Jiao, Thomas E. Potok Jan 2006

Multimedia Correlation Analysis In Unstructured Peer-To-Peer Network, Bo Yang, A. R. Hurson, Yu Jiao, Thomas E. Potok

Computer Science Faculty Research & Creative Works

Recent years saw the rapid development of peer-topeer (P2P) networks in a great variety of applications. However, similarity-based k-nearest-neighbor retrieval (k-NN) is still a challenging task in P2P networks due to the multiple constraints such as the dynamic topologies and the unpredictable data updates. Caching is an attractive solution that reduces network traffic and hence could remedy the technological constraints of P2P networks. However, traditional caching techniques have some major shortcomings that make them unsuitable for similarity search, such as the lack of semantic locality representation and the rigidness of exact matching on data objects. To facilitate the efficient similarity …

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Energy And Communication Efficient Group Key Management Protocol For Hierarchical Sensor Networks, Biswajit Panja, Sanjay Kumar Madria, Bharat Bhargava Jan 2006

Energy And Communication Efficient Group Key Management Protocol For Hierarchical Sensor Networks, Biswajit Panja, Sanjay Kumar Madria, Bharat Bhargava

Computer Science Faculty Research & Creative Works

In this paper, we describe group key management protocosl for hierarchical sensor networks where instead of using pre-deployed keys, each sensor node generates a partial key dynamically using a function. The function takes partial keys of its children as input. The design of the protocol is motivated by the fact that traditional cryptographic techniques are impractical in sensor networks because of high energy and computational overheads. The group key management protocol supports the establishment of two types of group keys; one for the sensor nodes within a group, and the other in a group of cluster heads. The protocol handles …

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Separation And Quantification Of N-Acetylcysteine-Amide (Naca) By Hplc With Fluorescence Detection, Wei Wu, Glenn Goldstein, Craig D. Adams, Richard H. Matthews, Nuran Ercal Jan 2006

Separation And Quantification Of N-Acetylcysteine-Amide (Naca) By Hplc With Fluorescence Detection, Wei Wu, Glenn Goldstein, Craig D. Adams, Richard H. Matthews, Nuran Ercal

Chemistry Faculty Research & Creative Works

N-acetyl-l-cysteine (NAC) is a well-known antioxidant that is capable of facilitating glutathione (GSH) biosynthesis and replenishing intracellular GSH under oxidatively challenging circumstances. N-acetyl-cysteine-amide (NACA), the amide form of NAC, is a newly designed and synthesized thiol-containing compound which is believed to be more lipophilic and permeable through cell membranes than NAC. The metabolic and antioxidant effects of these compounds in vitro and in vivo are under investigation. However, an analytical method that can separate and quantify both compounds simultaneously is not yet available, to the best of our knowledge. Because of their structural similarities, the two compounds are difficult to …

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Effective Inter-Organizational Information And Communication Technology Adoption In Business-To-Business Customer Interface, Sanna Maria Kallioranta Jan 2006

Effective Inter-Organizational Information And Communication Technology Adoption In Business-To-Business Customer Interface, Sanna Maria Kallioranta

LSU Doctoral Dissertations

Past research has found that 80-90 percent of IT investments do not meet corporate performance objectives, primarily due to non-technical reasons such as human and organizational aspects. When Inter-organizational Information and Communication Technology (IICT) implementation is properly managed IICT can help manage the flow of goods, services, and information between business partners in the supplier-customer dyad, thus reducing transaction costs along the entire value chain. Using the underlying Resource-Based View theoretical foundation, this research approaches effective IICT implementation capability as a holistic organizational capability that extends beyond tangible IT resources. This research investigates business outcomes of IICT adoption in the …

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Magnetic And Mossbauer Spectroscopy Studies Of Nanocrystalline Iron Oxide Aerogels, E. E. Carpenter, J. W. Long, D. R. Rolison, M. S. Logan, K. Pettigrew, R. M. Stroud, L. Theil Kuhn, B. Rosendahl Hasen, S. Mørup Jan 2006

Magnetic And Mossbauer Spectroscopy Studies Of Nanocrystalline Iron Oxide Aerogels, E. E. Carpenter, J. W. Long, D. R. Rolison, M. S. Logan, K. Pettigrew, R. M. Stroud, L. Theil Kuhn, B. Rosendahl Hasen, S. Mørup

Chemistry Publications

A sol-gel synthesis was used to produce iron oxide aerogels. These nanocrystalline aerogels have a pore-solid structure similar to silica aerogels but are composed entirely of iron oxides. Mössbauer experiments and x-ray diffraction showed that the as-prepared aerogel is an amorphous or poorly crystalline iron oxide, which crystallized as a partially oxidized magnetite during heating in argon. After further heat treatment in air, the nanocrystallites are fully converted to maghemite. The particles are superparamagnetic at high temperatures, but the magnetic properties are strongly influenced by magnetic interactions between the particles at lower temperatures.

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