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2006

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Two Way Diffusion Model For The Recording Mechanism In A Self-Developing Dry Acrylamide Photopolymer, Suzanne Martin, Izabela Naydenova, Raghavendra Jallapuram, Robert Howard, Vincent Toal Jan 2006

Two Way Diffusion Model For The Recording Mechanism In A Self-Developing Dry Acrylamide Photopolymer, Suzanne Martin, Izabela Naydenova, Raghavendra Jallapuram, Robert Howard, Vincent Toal

Conference Papers

In our most recent study [1] diffusion constants were measured in the simplified monoacrylamide version of a dry acrylamide based photopolymer holographic recording material developed in the Centre for Industrial and Engineering Optics. In this paper we report diffusion constants for the commonly used photopolymer formulation, which also contains the crosslinker bisacrylamide. A physical model for the recording mechanism is proposed which explains the two way diffusion observed in both systems, and is in agreement with much of the previously observed behaviour of the material, particularly in regard to dependence of diffraction efficiency growth on spatial frequency and persistence of …

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In-Use Emission Measurements Of Snowmobiles And Snowcoaches In Yellowstone National Park, Gary A. Bishop, Daniel A. Burgard, Thomas R. Dalton, Donald H. Stedman Jan 2006

In-Use Emission Measurements Of Snowmobiles And Snowcoaches In Yellowstone National Park, Gary A. Bishop, Daniel A. Burgard, Thomas R. Dalton, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

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A Collision Avoidance System For Autonomous Underwater Vehicles, Chiew Seon Tan Jan 2006

A Collision Avoidance System For Autonomous Underwater Vehicles, Chiew Seon Tan

School of Engineering, Computing and Mathematics Theses

The work in this thesis is concerned with the development of a novel and practical collision avoidance system for autonomous underwater vehicles (AUVs). Synergistically, advanced stochastic motion planning methods, dynamics quantisation approaches, multivariable tracking controller designs, sonar data processing and workspace representation, are combined to enhance significantly the survivability of modern AUVs. The recent proliferation of autonomous AUV deployments for various missions such as seafloor surveying, scientific data gathering and mine hunting has demanded a substantial increase in vehicle autonomy. One matching requirement of such missions is to allow all the AUV to navigate safely in a dynamic and unstructured …

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The Role Of Technology Support Centres In Stimulating Entrepreneurship And Innovation In Sme Clusters, Aj Robotham, J Gatcha Jan 2006

The Role Of Technology Support Centres In Stimulating Entrepreneurship And Innovation In Sme Clusters, Aj Robotham, J Gatcha

School of Engineering, Computing and Mathematics

The Innovative Product Development Centre (IPDC) was established at the University of Wolverhampton in the West Midlands region of the UK with a mission “to help small and medium sized companies improve their business, secure jobs and contribute to the economic regeneration of the West Midlands Region”. Since 2000, the IPDC has helped several hundred enterprises to develop their businesses through innovation and new product development. Demand for help is high, which reflects a healthy desire by the SMEs to innovate. The assistance given is time limited, but its impact on the business is extremely varied. This paper will discuss …

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Nonlinear Interactions Of Waves And Currents With Structures In Nearshore Environments, Baoxing Wang Jan 2006

Nonlinear Interactions Of Waves And Currents With Structures In Nearshore Environments, Baoxing Wang

School of Engineering, Computing and Mathematics Theses

In this thesis, nonlinear interactions of waves and currents with structures in nearshore environments are investigated. The emphasis of the research is to model the encountered multiple scales of hydrodynamics (e. g. monochromatic waves and three-dimensional currents) in a numerically efficient and accurate way on a beach and around a structure in the shallow coastal region. The radiation stress and mass flux have been analytically derived by inclusion of higher-order surface elevations. The Boussinesq-type model COULWAVE is used to assess the fully nonlinear wave transformation on a beach. The research unveils the essential roles of the Ursell parameter, Irribarren number …

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Towards Non-Prescriptive Issues: A Teaching Framework For Selecting Marketing Dissertation Topics, Conor Horan Jan 2006

Towards Non-Prescriptive Issues: A Teaching Framework For Selecting Marketing Dissertation Topics, Conor Horan

Conference papers

There is a significant absence in academic literature, textbooks and practical teaching tools for advising or guiding student learning, in a practical non-prescriptive manner, toward topic selection and development. Prescriptive or rational approaches, taken by many research methods textbooks, are not adequate or sufficient when teaching this important first stage in the research process. Non-prescriptive approaches describing manageable steps should be researched more to fill this pedagogic gap. This paper attempts to promote academic discussion on a pedagogic gap that is broadly overlooked, and to examine how marketing and business academics can better instruct dissertation students in the area of …

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Implications Of Mass Education On Chemistry Higher Education, Christine O'Connor Jan 2006

Implications Of Mass Education On Chemistry Higher Education, Christine O'Connor

Level 3

The following paper discusses the implications of government policy for widening access and participation in third level institutes. The increase in ‘non-traditional’ students has been widely recognised on an international scale; however, some issues of inequality still exist. The ‘struggles’ associated with widening participation and the creation of a ‘new’ student type are discussed, with particular reference to chemistry education. A change is needed with regard to the pedagogical approach taken by staff in order to cater for a diverse student body comprising a broad range of learner types, and this must be supported both at departmental and institutional levels. …

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The Application Of Learning Skills In An Engineering Programme, Leslie Shoemaker Jan 2006

The Application Of Learning Skills In An Engineering Programme, Leslie Shoemaker

Level 3

At the Dublin Institute of Technology, an engineering programme in the School of Control Systems and Electrical Engineering has successfully incorporated a study skills module into the core curriculum. The module, titled Academic Development and Key Skills, is part of the first year of the programme and has a two-fold purpose. Primarily the goal is to assist the students with the transition from second level education to third level by teaching them a more competent learning style. This, in turn, helps to create a positive impact with respect to the retention of this student group within the programme. The second …

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Impact Of Dietary Carotenoid Deprivation On Macular Pigment And Serum Concentrations Of Lutein And Zeaxanthin, James Loughman, John Nolan, Stephan Beatty Jan 2006

Impact Of Dietary Carotenoid Deprivation On Macular Pigment And Serum Concentrations Of Lutein And Zeaxanthin, James Loughman, John Nolan, Stephan Beatty

Articles

No abstract provided.

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Can Blending Face-To-Face Teaching With E-Learning Support The Development Of Phase 4 Apprentices In Mathematics? A Formative Evaluation Research Study., Peter Hinch Jan 2006

Can Blending Face-To-Face Teaching With E-Learning Support The Development Of Phase 4 Apprentices In Mathematics? A Formative Evaluation Research Study., Peter Hinch

Theses

This thesis is a formative evaluation research study. Its purpose is to establish if blending face-to-face and e-learning delivery methods can support the development of Phase 4 apprentice plumbers in mathematics in the Department of Construction Skills in the Technologicl University Dublin. The study also included the design, development and evaluation of a mathematics web site called Plumatics 4 U which is grounded in established theoretical criteria for effective blended delivery within third level education. This web site is currently in use by Phase 4 apprentice plumbers and is delivered through WebCT. The CD accompanying this thesis contains a short …

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Using Sketches And Knowledge Bases For Geo-Spatial Image Retrieval, Michela Bertolotto, James Carswell, E Mcloughlin, D O'Sullivan, C Wilson Jan 2006

Using Sketches And Knowledge Bases For Geo-Spatial Image Retrieval, Michela Bertolotto, James Carswell, E Mcloughlin, D O'Sullivan, C Wilson

Articles

This paper presents research in the field of knowledge management for geo-spatial imagery including scanned aerial photos and satellite images. We have developed a web-based system that allows users to query a database of images not only using metadata, but also drawing sketches of configurations of objects they are interested in as well as inputting textual descriptions of their intended task. Our system integrates case-based reasoning techniques to form a knowledge base from previously issued queries that can be exploited to improve future query processing and to build organizational memory through experience capture. The effective design and implementation of a …

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Measured Stark Widths And Shifts Of The Neutral Argon Spectral Lines In 4s–4p And 4s–4p′ Transitions, Vladimir Milosavljevic, Albert R. Ellingboe, Stevan Djenize Jan 2006

Measured Stark Widths And Shifts Of The Neutral Argon Spectral Lines In 4s–4p And 4s–4p′ Transitions, Vladimir Milosavljevic, Albert R. Ellingboe, Stevan Djenize

Articles

We investigate the Stark widths (W) and the shift (d), of the seven neutral argon (Ar I) spectral lines from the 4s–4p and 4s–4p′ transitions. The line shapes are measured in a linear, low-pressure, optically thin pulsed arc discharge at about 16 000 K electron temperature (T) and about 7.0 × 1022 m− 3 electron density (N). The new data separates the electron width (We) and ion width Wi from the total Stark width (Wt), as well the separation of electron total Stark …

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A Study Of The Relationship Between The Number Of High School Science Credits Earned And Successful Completion Of The First Year Of College At A Regents’ Institution, Amy Denise Jabens Jan 2006

A Study Of The Relationship Between The Number Of High School Science Credits Earned And Successful Completion Of The First Year Of College At A Regents’ Institution, Amy Denise Jabens

Dissertations and Theses @ UNI

The purpose of this research was to study the relationship between the number of science credits a student completes at Prairie High School and the successful completion of his or her first year of college at an Iowa Regent's institution as defined by college grade point average and a minimum number of credits earned. Data for this study was collected from high school transcripts and Prairie High School's annual report from the Iowa State Board of Regents. This report outlines how many credits students earn and their cumulative grade point average at the end of their first year of college. …

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Neural Network Control Of Spark Ignition Engines With High Egr Levels, A. Singh, Brian C. Kaul, J. A. Drallmeier, Jagannathan Sarangapani, Jonathan B. Vance Jan 2006

Neural Network Control Of Spark Ignition Engines With High Egr Levels, A. Singh, Brian C. Kaul, J. A. Drallmeier, Jagannathan Sarangapani, Jonathan B. Vance

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Research has shown substantial reductions in the oxides of nitrogen (NOx) concentrations by using 10% to 25% exhaust gas recirculation (EGR) in spark ignition (SI) engines [1]. However under high EGR levels the engine exhibits strong cyclic dispersion in heat release which may lead to instability and unsatisfactory performance. A suite of neural network (NN)-based output feedback controllers with and without reinforcement learning is developed to control the SI engine at high levels of EGR even when the engine dynamics are unknown by using fuel as the control input. A separate control loop was designed for controlling EGR levels. The …

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Effects Of Welding Current In Gas Metal Arc Welding, Junling Hu, Tai Lung Tsai Jan 2006

Effects Of Welding Current In Gas Metal Arc Welding, Junling Hu, Tai Lung Tsai

Mechanical and Aerospace Engineering Faculty Research & Creative Works

In gas metal arc welding (GMAW), current is one of the most important factors affecting the mode of metal transfer, weld pool dynamics and subsequently the weld quality. in this paper, the comprehensive model recently developed by the authors was used to study the effects of different current levels on the droplet formation, plasma generation, metal transfer, and weld pool dynamics in GMA welding. Two welding currents were studied, including one low current and one high current. at each current level, the transient temperature and velocity distributions of the arc plasma and the molten metal, and the shapes of the …

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Theoretical Treatment Of Electron-Impact Ionization Of Molecules, Junfang Gao, Jerry Peacher, Don H. Madison Jan 2006

Theoretical Treatment Of Electron-Impact Ionization Of Molecules, Junfang Gao, Jerry Peacher, Don H. Madison

Physics Faculty Research & Creative Works

There is currently no reliable theory for calculating the fully differential cross section (FDCS) for low energy electron-impact ionization of molecules. All of the existing experimental FDCS data represent averages over all molecular orientations and this can be an important theoretical complication for calculations that are computer intensive. We have found that using an averaged molecular orbital is an accurate approximation for ionization of ground states. In this paper, we will describe the approximation, discuss its expected range of validity and show some FDCS results using the approximation for ionization of H2 and N2

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Ultraviolet Lasing In High-Order Bands Of Three-Dimensional Zno Photonic Crystals, Michael Scharrer, Alexey Yamilov, Xiaohua Wu, Hui Cao, Robert P. H. Chang Jan 2006

Ultraviolet Lasing In High-Order Bands Of Three-Dimensional Zno Photonic Crystals, Michael Scharrer, Alexey Yamilov, Xiaohua Wu, Hui Cao, Robert P. H. Chang

Physics Faculty Research & Creative Works

UV lasing in three-dimensional ZnO photonic crystals is demonstrated at room temperature. The photonic crystals are inverse opals with high refractive index contrast that simultaneously confine light and provide optical gain. Highly directional lasing with tunable wavelength is obtained by optical pumping. Comparison of the experimental results to the calculated band structure shows that lasing occurs in high-order bands with abnormally low group velocity. This demonstrates that the high-order band structure of three-dimensional photonic crystals can be used to effectively confine light and enhance emission. Our findings may also impact other applications of photonic crystal devices. ©2006 American Institute of …

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Experimental And Theoretical (E,2e) Ionization Cross Sections For A Hydrogen Target At 75.3 Ev Incident Energy In A Coplanar Asymmetric Geometry, Junfang Gao, Don H. Madison, Jerry Peacher, Andrew James Murray, Martyn J. Hussey Jan 2006

Experimental And Theoretical (E,2e) Ionization Cross Sections For A Hydrogen Target At 75.3 Ev Incident Energy In A Coplanar Asymmetric Geometry, Junfang Gao, Don H. Madison, Jerry Peacher, Andrew James Murray, Martyn J. Hussey

Physics Faculty Research & Creative Works

Very recently it was shown that the molecular three-body distorted wave (M3DW) approach gives good agreement with the shape of the experimental data for electron-impact ionization of H2 in a coplanar symmetric geometry, providing the incident electrons have an energy of 35 eV or greater. One of the weaknesses of these studies was that only the shape of the cross section could be compared to experiment, since there was no absolute or relative normalization of the data. Here we report a joint experimental/theoretical study of electron-impact ionization of H2 in a coplanar asymmetric geometry where the energy of …

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Ionization Of Atoms With Spin Polarized Electrons, J. Lower, S. Bellm, R. Panajotovic, E. Weigold, A. Prideaux, Z. Stegen, Don H. Madison, Colm T. Whelan, B. Lohmann Jan 2006

Ionization Of Atoms With Spin Polarized Electrons, J. Lower, S. Bellm, R. Panajotovic, E. Weigold, A. Prideaux, Z. Stegen, Don H. Madison, Colm T. Whelan, B. Lohmann

Physics Faculty Research & Creative Works

The most detailed insight into the process of electron impact-induced ionization of atomic species is provided by measurements in which both kinematical and quantum mechanical variables are determined. Here we describe recent (e,2e) experimental and theoretical studies involving the ionization of xenon and argon by spin-polarized electrons in which the fine-structure levels of the ion are energetically resolved. Such investigations shed light on the mechanisms driving the ionization reaction and the role of exchange and relativistic processes.

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Kinematically Complete Experiment On Single Ionization In 75-Kev P+He Collisions, Michael Schulz, Ahmad Hasan, N. V. Maydanyuk, M. Foster, B. Tooke, Don H. Madison Jan 2006

Kinematically Complete Experiment On Single Ionization In 75-Kev P+He Collisions, Michael Schulz, Ahmad Hasan, N. V. Maydanyuk, M. Foster, B. Tooke, Don H. Madison

Physics Faculty Research & Creative Works

We have measured and calculated fully differential single-ionization cross sections for the complete three-dimensional space in 75 keV p+He collisions. Several signatures of the projectile-residual-target-ion interaction, some of which are not observable for fast projectiles and for electron impact, are revealed. Some of these features are qualitatively reproduced by our calculations if this interaction is accounted for. However, overall the agreement between theory and experiment is not very good. Thus, our understanding of effects caused by the projectile-residual-target-ion interaction appears to be rather incomplete.

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Magnetically Mediated Transparent Conductors: In₂O₃ Doped With Mo, Julia E. Medvedeva Jan 2006

Magnetically Mediated Transparent Conductors: In₂O₃ Doped With Mo, Julia E. Medvedeva

Physics Faculty Research & Creative Works

First-principles band structure investigations of the electronic, optical, and magnetic properties of Mo-doped In2O3 reveal the vital role of magnetic interactions in determining both the electrical conductivity and the Burstein-Moss shift which governs optical absorption. We demonstrate the advantages of the transition metal doping which results in smaller effective mass, larger fundamental band gap, and better overall optical transmission in the visible as compared to commercial Sn-doped In2O3. Similar behavior is expected upon doping with other transition metals opening up an avenue for the family of efficient transparent conductors mediated by magnetic interactions.

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Quantum Phase Transitions Of The Diluted O(3) Rotor Model, Thomas Vojta, Rastko Sknepnek Jan 2006

Quantum Phase Transitions Of The Diluted O(3) Rotor Model, Thomas Vojta, Rastko Sknepnek

Physics Faculty Research & Creative Works

We study the phase diagram and the quantum phase transitions of a site-diluted two-dimensional O(3) quantum rotor model by means of large-scale Monte Carlo simulations. This system has two quantum phase transitions: a generic one for small dilutions and a percolation transition across the lattice percolation threshold. We determine the critical behavior for both transitions and for the multicritical point that separates them. In contrast to the exotic scaling scenarios found in other random quantum systems, all these transitions are characterized by finite-disorder fixed points with power-law scaling. We relate our findings to a recent classification of phase transitions with …

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Spin Excitations In Fluctuating Stripe Phases Of Doped Cuprate Superconductors, Matthias Vojta, Thomas Vojta, Ribhu K. Kaul Jan 2006

Spin Excitations In Fluctuating Stripe Phases Of Doped Cuprate Superconductors, Matthias Vojta, Thomas Vojta, Ribhu K. Kaul

Physics Faculty Research & Creative Works

Using a phenomenological lattice model of coupled spin and charge modes, we determine the spin susceptibility in the presence of fluctuating stripe charge order. We assume the charge fluctuations to be slow compared to those of the spins, and combine Monte Carlo simulations for the charge order parameter with exact diagonalization of the spin sector. Our calculations unify the spin dynamics of both static and fluctuating stripe phases and support the notion of a universal spin excitation spectrum in doped cuprate superconductors.

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Bacteria Foraging: A New Tool For Simultaneous Robust Design Of Upfc Controllers, M. Tripathy, S. Mishra, Ganesh K. Venayagamoorthy Jan 2006

Bacteria Foraging: A New Tool For Simultaneous Robust Design Of Upfc Controllers, M. Tripathy, S. Mishra, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

Robust tuning of lead-lag type controller used for regulating FACTS control signal to improve dynamic stability has been an area of interest in research. This paper presents a new approach based on the foraging behavior of E. coli Bacteria in the human intestine, to optimize simultaneously three constants each of four lead-lag type UPFC controller present in a Single Machine Infinite Bus (SMIB) power system. For the tuning purpose, a multi-objective cost function is formulated that accounts for damping factors and ratios of various system modes for a wide range of operating conditions. Robustness of the proposed tuning method is …

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A Hierarchical Secure Routing Protocol Against Black Hole Attacks In Sensor Networks, Jian Yin, Sanjay Kumar Madria Jan 2006

A Hierarchical Secure Routing Protocol Against Black Hole Attacks In Sensor Networks, Jian Yin, Sanjay Kumar Madria

Computer Science Faculty Research & Creative Works

A black hole attack is a severe attack that can be easily employed against routing in sensor networks. In a black hole attack, a malicious node spuriously announces a short route to the sink node (the destination) to attract additional traffic to the malicious node and then drops them. In this paper, we propose a hierarchical secure routing protocol for detecting and defending against black hole attacks. The proposed protocol uses only symmetric key cryptography to discover a safe route against black hole attacks. The comparison of the proposed protocol with two other existing approaches proves that the proposed scheme …

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An Internet Based Intelligent Argumentation System For Collaborative Engineering Design, Xiaoqing Frank Liu, Samir Raorane, Man Zheng, Ming-Chuan Leu Jan 2006

An Internet Based Intelligent Argumentation System For Collaborative Engineering Design, Xiaoqing Frank Liu, Samir Raorane, Man Zheng, Ming-Chuan Leu

Computer Science Faculty Research & Creative Works

Modern product design is a very complicated process which involves groups of designers, manufacturers, suppliers, and customer representatives. Conflicts are unavoidable in collaboration among multiple stakeholders, who have different objectives, requirements, and priorities. Unfortunately, current web-based collaborative engineering design systems do not support collaborative conflict resolution. In this paper, we will develop an intelligent computational argumentation model to enable management of a large scale argumentation network, and resolution of conflicts based on argumentation from many participants. A web-based intelligent argumentation tool is developed as a part of a web-based collaborative engineering design system based on the above model to resolve …

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Cadre: A Collaborative Replica Allocation And Deallocation Approach For Mobile-P2p Networks, Anirban Mondal, Sanjay Kumar Madria, Masaru Kitsuregawa Jan 2006

Cadre: A Collaborative Replica Allocation And Deallocation Approach For Mobile-P2p Networks, Anirban Mondal, Sanjay Kumar Madria, Masaru Kitsuregawa

Computer Science Faculty Research & Creative Works

This paper proposes CADRE (Collaborative Allocation and Deallocation of Replicas with Efficiency), a dynamic replication scheme for improving the typically low data availability in mobile ad-hoc peer-to-peer (M-P2P) networks. The main contributions of CADRE are two-fold. First, it collaboratively performs both replica allocation and deallocation in tandem to facilitate optimal replication and to avoid 'thrashing' conditions. Second, it addresses fair replica allocation across the MHs. CADRE deploys a hybrid super-peer architecture in which some of the MHs act as the 'gateway nodes' (GNs) in a given region. GNs facilitate both search and replication. Our performance study indicates that CADRE indeed …

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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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Generalized Distance Metric As A Robust Similarity Measure For Mobile Object Trajectories, Garima Pathak, Sanjay Kumar Madria, Spandan Tiwari Jan 2006

Generalized Distance Metric As A Robust Similarity Measure For Mobile Object Trajectories, Garima Pathak, Sanjay Kumar Madria, Spandan Tiwari

Computer Science Faculty Research & Creative Works

In this paper, we propose a novel generalized distance metric based on a model that incorporates the time axis explicitly. The proposed metric is based fundamentally on the Mahalanobis distance metric, which eliminates the correlation and scaling errors in similarity searches on trajectory databases. We propose the incorporation of a weight matrix in the proposed distance metric, which allows for easy manipulation of the degree of significance of the different spatial and or temporal dimensions.

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Improving Channel Throughput Of Wlans And Ad Hoc Networks Using Explicit Denial Of Requests, Maggie Xiaoyan Cheng, Yadi Ma, Yi Wang Jan 2006

Improving Channel Throughput Of Wlans And Ad Hoc Networks Using Explicit Denial Of Requests, Maggie Xiaoyan Cheng, Yadi Ma, Yi Wang

Computer Science Faculty Research & Creative Works

A new Multiple Access Control scheme for wireless ad hoc networks and WLANs is proposed. This scheme uses explicit denial of channel requests and a busy tone to improve channel throughput. Performance analysis shows significant improvement when the network is under heavy traffic load.

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