Digital Commons Network^™

The Context-Oriented Architecture: Integrating Context Into Semantic Web Services, Aisha Mohamed-Salama Elsafty

Archived Theses and Dissertations

No abstract provided.

Inventions On Using Ldap For Different Purposes-Part-1, Umakant Mishra

Umakant Mishra

The objective of this article is to know how is LDAP used for applications in e-commerce and Policy Management. The analysis of patents shows which Inventive Principles have been used to solve those inventions. Unlike other parts of the study which have tried to improve certain aspect of LDAP technology and application, this article includes the inventions that use LDAP for various different purposes. This article is divided into 3 parts for convenience of size. The first part of the article includes 6 patents using LDAP for “e-commerce” and “Policy Management”. The second part includes 10 patents using LDAP for …

What’S The Hang Up? The Future Of Voip Regulation And Taxation In New Hampshire, Kate Winstanley

The University of New Hampshire Law Review

Alice in Austria wishes to call her friend Bob in Boston, using a Boston area code to avoid charges for an international call. Using VoIP, Alice may initiate her call from any location in Austria where she may find Internet access. Once Alice connects to the Internet, she can transmit her call with the aid of a VoIP service provider, such as Skype. In order to hear and communicate with Bob, Alice can rely on a microphone and a headset that she can plug into her computer. Through VoIP, not only may Alice carry on a telephone conversation, but most …

Inventions On Ldap Data Management- A Triz Based Analysis, Umakant Mishra

Umakant Mishra

The data model of LDAP is same as X.500 data model. The LDAP protocol assumes there are one or more servers, which jointly provide access to a Directory Information Tree (DIT). The tree is made up of entries. Entries have relative distinguished name (RDN), which must be unique among all its siblings. The concatenation of the relative distinguished names from a particular entry to an immediate subordinate of the root of the tree forms the Distinguished Name (DN) for that entry. (IETF, RFC 2251).

LDAP provides add, delete and modify operations for data modification. Each of these LDAP update operation …

Inventions On Using Ldap For Different Purposes-Part-3, Umakant Mishra

Umakant Mishra

Unlike other parts of the study which have tried to improve certain aspect of LDAP technology and application, this article includes the inventions that use LDAP for various different purposes. This article is divided into 3 parts for convenience of size. The first part of the article includes 6 patents using LDAP for “e-commerce” and “Policy Management”. The second part includes 10 patents using LDAP for “Network Management” and “Telecommunications”. The third part of the article includes 11 patents using LDAP for “World Wide Web” and “Java and CORBA”. This is the third part of the article which analyses patents …

Inventions On Using Ldap For Different Purposes (Part-2) - A Triz Based Analysis Of Us Patents, Umakant Mishra

Umakant Mishra

The objective of this article is to know how is LDAP used for Network Management and Telecommunications. The analysis of patents shows which Inventive Principles have been used to solve those inventions. Unlike other parts of the study which have tried to improve certain aspect of LDAP technology and application, this article includes the inventions that use LDAP for various different purposes. This article is divided into 3 parts for convenience of size. The first part of the article includes 6 patents using LDAP for “e-commerce” and “Policy Management”. The second part includes 10 patents using LDAP for “Network Management” …

Inventions On Integrating Ldap With Other Directories - A Triz Based Analysis Of Us Patents, Umakant Mishra

Umakant Mishra

Thus the LDAP architecture allows multiple LDAP servers work together on the same directory tree or multiple directory trees. Besides, LDAP being built on an open architecture, it is quite possible to integrate with other directory servers. LDAP can be mapped onto any other directory system so long as the X.500 data and service model as used in LDAP is not violated in LDAP interface. LDAP server may store data in a Flat file, in RDBMS or in any other database. The LDAP client applications can use LDAP directory interface without having knowledge on the underlying data storage mechanism. However, …

Evolution Of User Interfaces For The Visually Impaired- Part 2, Umakant Mishra

Umakant Mishra

Physically or mentally challenged people cannot use a computer in the same way a normal people can. For example, a person with disability in hands cannot use a standard keyboard or mouse efficiently. People having hearing problem, visual challenge etc. cannot interact with a computer like a normal person. So it is necessary to specially design the computers, interfacing devices and software interfaces, which can be used by the physically challenged people.

This article analyses the types of visual disabilities, different assistive technologies for different visual disabilities, guidelines for developing user interfaces for the visually impaired, software products available for …

An Experimental Analysis Of The Call Capacity Of Ieee 802.11b Wireless Local Area Networks For Voip Telephony, Brian Keegan, Mark Davis

Conference papers

In this paper we present the results from an experimental study of the call capacity of an IEEE 802.11b network when using VoIP telephony. Experiments include increasing the number of VoIP users in a wireless test-bed and increasing the level of background traffic until network saturation occurs. The experiments allow us to perform an analysis of the access point (AP) buffer dynamics. Results show that the network is capable of supporting up to 16 VoIP stations (STAs). Due to the operation of the IEEE 802.11 medium access control (MAC) mechanism, the AP acts as a bottleneck for all traffic destined …

Web Services - Based Autonomic Computing Framework (Wsac), Sherif Atef Gurguis

Archived Theses and Dissertations

No abstract provided.

Location Estimation In A 3d Environment Using Radio Frequency Identification Tags, Adwitiya Akash Jain

Theses

RFID tag location estimation in a 3D environment is investigated. The location of the tag with unknown coordinates can be estimated with certain accuracy. However, accuracy can be improved using the knowledge based on measurement of additional reference tags with known location. This thesis studies the mathematical formulation and practical realization of location sensing using RFID tags.

Deviating from the standard use of RFID technology which employs one tag reader to identify the presence of tag, here multiple tag readers with known location are used to estimate the physical location of an individual tag, with/without the help of few reference …

New Hybrid Automatic Repeat Request (Harq) Scheme For 4x4 Mimo System, Based On The Extended Alamouti Quasi-Orthogonal Space-Time Bloc Coding (Q-Stbc), In Invariant And Variant Fading Channel, Jordi Ferrer Torras

Theses

A new Hybrid Automatic Repeat reQuest (HARQ) combining scheme for a 4x4 Multiple Input Multiple Output (MIMO) system in invariant and variant fading channel conditions is proposed and analized. Based on the Extended Alamouti Quasi-orthogonal Space-Time Block Coding (Q-STBC), the use of the so-called Alternative Matrices for transmission, depending on the Channel State Information (CSI) received as feedback, is compared to other existing solutions.

Sign changes and permutations in the retransmission sequences allow reducing the interference while exploiting the spatial diversity to introduce some gain in the signal power. The best transmission order is selected by the Determinant Criterion, which …

Evolution Of User Interfaces For The Visually Impaired- Part- 1, Umakant Mishra

Umakant Mishra

Physically or mentally challenged people cannot use a computer in the same way a normal people can. For example, a person with disability in hands cannot use a standard keyboard or mouse efficiently. People having hearing problem, visual challenge etc. cannot interact with a computer like a normal person. So it is necessary to specially design the computers, interfacing devices and software interfaces, which can be used by the physically challenged people.

There are many special devices like mouse, keyboard, pointers, and touch screens etc. to assist the visually challenged users. It is a challenge for the inventors and manufacturers …

End-To-End Latency Of A Fault-Tolerant Corba Infrastructure, Wenbing Zhao, Louise E. Moser, P. Michale Melliar-Smith

Electrical and Computer Engineering Faculty Publications

This paper presents an evaluation of the end-to-end latency of a fault-tolerant CORBA infrastructure that we have implemented. The fault-tolerant infrastructure replicates the server applications using active, passive and semi-active replication, and maintains strong replica consistency of the server replicas. By analyses and by measurements of the running fault-tolerant infrastructure, we characterize the end-to-end latency under fault-free conditions. The main determining factor of the run-time performance of the fault-tolerant infrastructure is the Totem group communication protocol, which contributes to the end-to-end latency primarily in …

Supplementing An Ad-Hoc Wireless Network Routing Protocol With Radio Frequency Identification (Rfid) Tags, Leroy S. Willemsen

Theses and Dissertations

Wireless sensor networks (WSNs) have a broad and varied range of applications, yet all of these are limited by the resources available to the sensor nodes that make up the WSN. The most significant resource is energy. A WSN may be deployed to an inhospitable or unreachable area, leaving it with a non-replenishable power source. This research examines a way of reducing energy consumption by augmenting the nodes with radio frequency identification (RFID) tags that contain routing information. It was expected that RFID tags would reduce the network throughput, the ad hoc on-demand distance vector (AODV) routing traffic sent, and …

Optimal Coverage Of Theater Targets With Small Satellite Constellations, Axel Rendon

Theses and Dissertations

The daylight passes of a low-Earth orbit satellite over a targeted latitude and longitude are optimized by varying the inclination and eccentricity of an orbit at different altitudes. This investigation extends the work by Emery et al, in which the optimal Right Ascension of the Ascending Node was determined for a circular, matched inclination orbit. The optimal values were determined by a numerical research method based on Emery et al's Matlab program. Results indicate that small increases in inclination raise the number of daylight passes up to 33%. These optimal inclinations depend on the satellite semi-major axis. Eccentricity increases also …

Characterization And Design Of High-Level Vhdl I/Q Frequency Downconverter Via Special Sampling Scheme, Jesse P. Somann

Theses and Dissertations

This study explores the characterization and implementation of a Special Sampling Scheme (SSS) for In-Phase and Quad-Phase (I/Q) down conversion utilizing top-level, portable design strategies. The SSS is an under-developed signal sampling methodology that can be used with military and industry receiver systems, specifically, United States Air Force (USAF) video receiver systems. The SSS processes a digital input signal-stream sampled at a specified sampling frequency, and down converts it into In-Phase (I) and Quad-Phase (Q) output signal-streams. Using the theory and application of the SSS, there are three main objectives that will be accomplished: characterization of the effects of input, …

A Gradient-Based Optimum Block Adaptation Ica Technique For Interference Suppression In Highly Dynamic Communication Channels, Wasfy B. Mikhael, Tianyu Yang

Department of Electrical Engineering and Computer Science - Daytona Beach

The fast fixed-point independent component analysis (ICA) algorithm has been widely used in various applications because of its fast convergence and superior performance. However, in a highly dynamic environment, real-time adaptation is necessary to track the variations of the mixing matrix. In this scenario, the gradient-based online learning algorithm performs better, but its convergence is slow, and depends on a proper choice of convergence factor. This paper develops a gradient-based optimum block adaptive ICA algorithm (OBA/ICA) that combines the advantages of the two algorithms. Simulation results for telecommunication applications indicate that the resulting performance is superior under time-varying conditions, which …

New Hybrid Automatic Repeat Request (Harq) Combining With Space Time Block Coding (Stbc) In Invariant And Variant Fading Channel, Guillem Ernest Malagarriga Vilella

Theses

Hybrid Automatic Repeat reQuest (HARQ) combining for space time block coding Multiple Input Multiple Output (MIMO) system consisting of N transmit antennas and M receive antennas (NxM) in a time invariant channel and in a time varying channel is proposed and its performance is analyzed. Based on the measured channel matrix, the receiver chooses the best retransmission order and communicated it to the transmitter.

The scheme, where this algorithm is performed, is a combination of a precombining HARQ scheme and the Multiple Alamouti Space-Time Block Coding (MASTBC), which is suitable for more than 2 transmit antennas. The combination of this …

Mimo Communications In Ad Hoc Networks, Biao Chen, Michael J. Gans

Electrical Engineering and Computer Science - All Scholarship

We study in this paper the network spectral efficiency in terms of bits/s/Hz of a MIMO (multiple-input multiple output) ad hoc network with K simultaneous communicating transmitter-receiver pairs. Assume that each transmitter is equipped with t antennas and each receiver implements single user detection. We show that in the absence of channel state information (CSI) at the transmitters, the asymptotic network spectral efficiency is limited by r nats/s/Hz as K -> ∞ and is independent of t and the transmit power. With CSI corresponding to the desired receiver available at the transmitter, we demonstrate that the asymptotic spectral efficiency is …

Mimo Communications In Ad Hoc Networks, Biao Chen, Michael J. Gans

Electrical Engineering and Computer Science - All Scholarship

We study in this paper the network spectral efficiency in terms of bits/s/Hz of a MIMO (multiple-input multiple output) ad hoc network with K simultaneous communicating transmitter-receiver pairs. Assume that each transmitter is equipped with t antennas and each receiver implements single user detection. We show that in the absence of channel state information (CSI) at the transmitters, the asymptotic network spectral efficiency is limited by r nats/s/Hz as K -> ∞ and is independent of t and the transmit power. With CSI corresponding to the desired receiver available at the transmitter, we demonstrate that the asymptotic spectral efficiency is …

Efficient Scheduling For Sdmg Cioq Switches, Mei Yang, S. Q. Zheng

Electrical & Computer Engineering Faculty Research

Combined input and output queuing (CIOQ) switches are being considered as high-performance switch architectures due to their ability to achieve 100% throughput and perfectly emulate output queuing (OQ) switch performance with a small speedup factor S. To realize a speedup factor S, a conventional CIOQ switch requires the switching fabric and memories to operate S times faster than the line rate. In this paper, we propose to use a CIOQ switch with space-division multiplexing expansion and grouped input/output ports (SDMG CIOQ switch for short) to realize speedup while only requiring the switching fabric and memories to operate at the line …

Free Roaming: A System For Ubiquitous Computing, Huanjin Liu

Theses Digitization Project

Based on the Umbilical Cord system, this project enriches the Ubiquitous Computing system with a Free Roaming system. This Free Roaming consists of a distributed authentication system, a data caching system and a communication system between them. It allows user to roam within this system and access his data everywhere. Together with the Umbilical Cord system, a Ubiquitous Computing system is functionally completed as a prototype, and is ready to be deployed into the Internet.

Fedcor: An Institutional Cordra Registry, Giridhar Manepalli, Henry Jerez, Michael L. Nelson

Computer Science Faculty Publications

FeDCOR (Federation of DSpace using CORDRA) is a registry-based federation system for DSpace instances. It is based on the CORDRA model. The first article in this issue of D-Lib Magazine describes the Advanced Distributed Learning-Registry (ADL-R) [1], which is the first operational CORDRA registry, and also includes an introduction to CORDRA. That introduction, or other prior knowledge of the CORDRA effort, is recommended for the best understanding of this article, which builds on that base to describe in detail the FeDCOR approach.

On The Performance Evaluation Of High-Speed Transport Protocols, Bridget Hillyer

UNF Graduate Theses and Dissertations

As high-speed networks with large bandwidth delay products (BDP) become more common, high-speed transport protocols must be developed that perform well in these contexts. TCP has limitations in high BDP networks. A number of high-speed TCP proposals have emerged, including BIC TCP, High Speed TCP, and H-TCP. XCP is an intraprotocol communication mechanism that promises even greater performance by providing explicit feedback from routers about congestion. It requires changes to routers and end hosts, though, whereas the other experimental protocols only require changes to an end host. We evaluated the performance ofXCP against BIC TCP, High Speed TCP, H-TCP, and …

Network Neutrality And The Economics Of Congestion, Christopher S. Yoo

All Faculty Scholarship

No abstract provided.

Observed Web Robot Behavior On Decaying Web Subsites, Joan A. Smith, Frank Mccown, Michael L. Nelson

Computer Science Faculty Publications

We describe the observed crawling patterns of various search engines (including Google, Yahoo and MSN) as they traverse a series of web subsites whose contents decay at predetermined rates. We plot the progress of the crawlers through the subsites, and their behaviors regarding the various file types included in the web subsites. We chose decaying subsites because we were originally interested in tracking the implication of using search engine caches for digital preservation. However, some of the crawling behaviors themselves proved to be interesting and have implications on using a search engine as an interface to a digital library.

Linux Based Pda Gateway For Wireless Sensor Networks, Áine Mccarthy

Theses

Recent years have seen a dramatic increase in the development and deployment of intelligent sensors and their use with a plethora of networking protocol technologies. Wireless Sensor Networks (WSN) can be used to monitor the environment, objects in the environment and the interaction of these objects with each other. Examples include environment and habitat monitoring, structural monitoring, disaster management and emergency response. The deployment of such large-scale WSN possess many challenges, the most important being scalability, portability, fault tolerance, adaptability and ubiquitous connectivity. There also exist many challenges when trying to establish communication with WSN. WSN can function as a …

Analysis Of Relay-Based Cellular Systems, Ansuya Negi

Dissertations and Theses

Relays can be used in cellular systems to increase coverage as well as reduce the total power consumed by mobiles in a cell. This latter benefit is particularly useful for mobiles operating on a depleted battery. The relay can be a mobile, a car or any other device with the appropriate communication capabilities. In thesis we analyze the impact of using relays under different situations. We first consider the problem of reducing total power consumed in the system by employing relays intelligently. We find that in a simulated, fully random, mobile cellular network for CDMA (Code Division Multiple Access), significant …

Design Of Survivable Wdm Network Based On Pre-Configured Protection Cycle, Byungkyu Kang

Theses: Doctorates and Masters

Wavelength Division Multiplexing (WDM) is an important technique which allows the trans- port of large quantities of data over optical networks. All optical WDM-based networks have been used to improve overall communication capacity and provide an excellent choice for the design of backbone networks. However, due to the high traffic load that each link can carry in a WDM network, survivability against failures becomes very important. Survivability in this context is the ability of the network to maintain continuity of service against failures, since a failure can lead to huge data losses. In recent years, many survivability mechanisms have been …