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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Dynamic data retrieval on the world wide web

Beryoza, Dmitriy 23 October 2000 (has links)
Methods for accessing data on the Web have been the focus of active research over the past few years. In this thesis we propose a method for representing Web sites as data sources. We designed a Data Extractor data retrieval solution that allows us to define queries to Web sites and process resulting data sets. Data Extractor is being integrated into the MSemODB heterogeneous database management system. With its help database queries can be distributed over both local and Web data sources within MSemODB framework. Data Extractor treats Web sites as data sources, controlling query execution and data retrieval. It works as an intermediary between the applications and the sites. Data Extractor utilizes a two-fold "custom wrapper" approach for information retrieval. Wrappers for the majority of sites are easily built using a powerful and expressive scripting language, while complex cases are processed using Java-based wrappers that utilize specially designed library of data retrieval, parsing and Web access routines. In addition to wrapper development we thoroughly investigate issues associated with Web site selection, analysis and processing. Data Extractor is designed to act as a data retrieval server, as well as an embedded data retrieval solution. We also use it to create mobile agents that are shipped over the Internet to the client's computer to perform data retrieval on behalf of the user. This approach allows Data Extractor to distribute and scale well. This study confirms feasibility of building custom wrappers for Web sites. This approach provides accuracy of data retrieval, and power and flexibility in handling of complex cases.
112

Multilingual interactive integrated multimedia based e-commerce

Chobe, Amol S. 15 May 2000 (has links)
As we approach the end of the twentieth century, E-commerce is a critical force shaping the world of today and tomorrow. E-commerce have introduced a new society where people can buy freely, anywhere, at anytime, across the globe on the web. There seems to be a market for consultants and outsourcing purveyors who will take your money and put together an online business for you. These are all very different markets, however. As lot of people speak different language than English, the concept of Multilingual Technology is essential. The primary purpose of this research paper is to study the Integrated Multimedia interaction with today's technology secondary purpose is to check out the Application of this technology in E -Commerce with the help of Multilingual technology. Multilingual-based E-commerce would prompt more widespread use of the types of services now available and prompt the development of new and better services and the benefits brought by information, technology, and information services available will be magnified and extended globally.
113

On-screen pre-deblurring of digital images using the wavefront aberration function of the human eye to improve computer access for the visually impaired

Alonso, Miguel 04 April 2003 (has links)
Traditional Optics has provided ways to compensate some common visual limitations (up to second order visual impairments) through spectacles or contact lenses. Recent developments in wavefront science make it possible to obtain an accurate model of the Point Spread Function (PSF) of the human eye. Through what is known as the "Wavefront Aberration Function" of the human eye, exact knowledge of the optical aberration of the human eye is possible, allowing a mathematical model of the PSF to be obtained. This model could be used to pre-compensate (inverse-filter) the images displayed on computer screens in order to counter the distortion in the user's eye. This project takes advantage of the fact that the wavefront aberration function, commonly expressed as a Zernike polynomial, can be generated from the ophthalmic prescription used to fit spectacles to a person. This allows the pre-compensation, or onscreen deblurring, to be done for various visual impairments, up to second order (commonly known as myopia, hyperopia, or astigmatism). The technique proposed towards that goal and results obtained using a lens, for which the PSF is known, that is introduced into the visual path of subjects without visual impairment will be presented. In addition to substituting the effect of spectacles or contact lenses in correcting the loworder visual limitations of the viewer, the significance of this approach is that it has the potential to address higher-order abnormalities in the eye, currently not correctable by simple means.
114

Remote control & communication of systems through power lines

Castillo, Joaquin 21 October 1997 (has links)
The remote control system proposed in this thesis will introduce the concept that power line can be used for control and communication. Home Automation has used the power line to send commands to control appliances but lacked the ability to achieve a two-way communication. The protocol used in Home Automation is not designed for communication and lacks some basics, like error detection. This thesis will not only use X-10 technology to communicate through the power line but will also implement a VHDL design used for the two-way communication. A cableless communication is developed using the power line since no new cabling is needed for communication. They greatly ease the work required to install a network, particularly in older buildings that were not built with cabling needs in mind. X-10 is not the only method that can be used for communication through the power line. A solution that needs further development is mentioned in the conclusion of this thesis.
115

Design and implementation of a web based shop floor control system to maintain schedule feasibility in a dynamic job shop environment

Bommakanti, Anil 07 December 1999 (has links)
The effective control of production activities in dynamic job shop with predetermined resource allocation for all the jobs entering the system is a unique manufacturing environment, which exists in the manufacturing industry. In this thesis a framework for an Internet based real time shop floor control system for such a dynamic job shop environment is introduced. The system aims to maintain the schedule feasibility of all the jobs entering the manufacturing system under any circumstance. The system is capable of deciding how often the manufacturing activities should be monitored to check for control decisions that need to be taken on the shop floor. The system will provide the decision maker real time notification to enable him to generate feasible alternate solutions in case a disturbance occurs on the shop floor. The control system is also capable of providing the customer with real time access to the status of the jobs on the shop floor. The communication between the controller, the user and the customer is through web based user friendly GUI. The proposed control system architecture and the interface for the communication system have been designed, developed and implemented.
116

A new algorithm for electroencephalogram functional brain mapping based on an auditory-comprehension process

Cabrerizo, Mercedes 12 June 2003 (has links)
The main objective of this thesis is to gain insight on the dynamics of the human brain through electroencephalography (EEG) analysis, with emphasis placed on the characterization of the effects of an Auditory/Comprehension task. A thorough examination of the EEG recordings was accomplished through the use of the most common brain waves (Alpha, Beta, Delta, and Theta). Conceivably, as the EEG recordings based on these tasks become better understood, their use as a helpful tool in mapping the different functions of the brain will become more effective. The EEG data was collected from 15 patients at Miami Children's Hospital using the ESI-256 system. A final evaluation of spectral arrays is performed based on comprehensive color topographic maps of the various induced brain activities. This representation allows us to bring out how different patients react under different circumstances, and to detect consequently neurological disorders such as the Attention Deficit Disorder (ADD).
117

The 128-bit block cipher MARS

Bose, Gourav 11 June 2003 (has links)
The purpose of the research is to investigate the emerging data security methodologies that will work with most suitable applications in the academic, industrial and commercial environments. Of several methodologies considered for Advanced Encryption Standard (AES), MARS (block cipher) developed by IBM, has been selected. Its design takes advantage of the powerful capabilities of modern computers to allow a much higher level of performance than can be obtained from less optimized algorithms such as Data Encryption Standards (DES). MARS is unique in combining virtually every design technique known to cryptographers in one algorithm. The thesis presents the performance of 128-bit cipher flexibility, which is a scaled down version of the algorithm MARS. The cryptosystem used showed equally comparable performance in speed, flexibility and security, with that of the original algorithm. The algorithm is considered to be very secure and robust and is expected to be implemented for most of the applications.
118

Web Service for Knowledge Management Information Tool (KMIT) Hotline module and its Security

Kondamudi, Harini 12 July 2010 (has links)
This thesis presents the development of a Web Service for the Hotline module of the Knowledge Management Information Tool (KMIT), a tool that is custom built for the decontamination & decommissionin (D&D) community of the Department Of Energy (DOE). The Hotline module allows interested users to post problems to specific areas of interest in the field of D&D. Various clients working with DOE and KMIT want to display the latest published problems of KMIT Hotline search in their own applications on a regular basis. Considering one of the major benefits of Web Services is the ease of integration of one piece of software with another, the Hotline Service is successfully developed and can be plugged into client’s applications by adding a reference to it. In such a distributed environment, messages can flow from node to node, through firewalls, onto the internet and through various intermediaries. This introduces a variety of message security threats. The research for this thesis included a study of the various security risks and scenarios. Appropriate security model is designed and is successfully implemented. Hotline Service can authenticate the client and ensure confidentiality making the service secure to communicate with
119

Digital signal processing implementation for near real-time wavelet transformation system for binary images

Alfonso, Ovidio 28 November 2000 (has links)
Communication has become an essential function in our civilization. With the increasing demand for communication channels, it is now necessary to find ways to optimize the use of their bandwidth. One way to achieve this is by transforming the information before it is transmitted. This transformation can be performed by several techniques. One of the newest of these techniques is the use of wavelets. Wavelet transformation refers to the act of breaking down a signal into components called details and trends by using small waveforms that have a zero average in the time domain. After this transformation the data can be compressed by discarding the details, transmitting the trends. In the receiving end, the trends are used to reconstruct the image. In this work, the wavelet used for the transformation of an image will be selected from a library of available bases. The accuracy of the reconstruction, after the details are discarded, is dependent on the wavelets chosen from the wavelet basis library. The system developed in this thesis takes a 2-D image and decomposes it using a wavelet bank. A digital signal processor is used to achieve near real-time performance in this transformation task. A contribution of this thesis project is the development of DSP-based test bed for the future development of new real-time wavelet transformation algorithms.
120

Diversifying the Internet

Liao, Yong 01 January 2010 (has links)
Diversity is a widely existing and much desired property in many networking systems. This dissertation studies diversity problems in Internet, which is the largest computer networking system in the world. The motivations of diversifying the Internet are two-fold. First, diversifying the Internet improves the Internet routing robustness and reliability. Most problems we have encountered in our daily use of Internet, such as service interruptions and service quality degradation, are rooted in the inter-domain routing system of Internet. Inter-domain routing is policy-based routing, where policies are often based on commercial agreements between ASes. Although people know how to safely accommodate a few commercial agreements in inter-domain routing, for a large set of diverse commercial agreements, it is not clear yet what policy guidelines can accommodate them and guarantee convergence. Accommodating diverse commercial agreements not only is needed for ASes in Internet to achieve their business goals, it also provides more path diversity in inter-domain routing, which potentially benefits the inter-domain routing system. However, more reliable and robust routing cannot be achieve unless the routing system exploits the path diversity well. However, that is not the case for the current inter-domain routing system. There exist many paths in the underlying network, but the routing system cannot find those paths promptly. Although many schemes have been proposed to address the routing reliability problem, they often add significant more complexity into the system. The need for a more reliable inter-domain routing system without adding too much complexity calls for designing practical schemes to better exploit Internet path diversity and provide more reliable routing service. The increasing demands of providing value-added services in Internet also motivates the research work in this dissertation. Recently, network virtualization substrates and data centers are becoming important infrastructures. Network virtualization provides the ability to run multiple concurrent virtual networks in the same shared substrate. To better facilitate building application-specific networks so as to test and deploy network innovations for future Internet, a network virtualization platform must provide both high-degree of flexibility and high-speed packet forwarding in virtual networks. However, flexibility and forwarding performance are often tightly coupled issues in system design. Usually we have to sacrifice one in order to improve the other one. The lack of a platform that has both flexibility and good forwarding performance motivates the research in this dissertation to design network virtualization platforms to better support virtual networks with diverse functionalities in future Internet. The popularity of data centers in Internet also motivates this dissertation to studying scalable and cost-efficient data center networks. Data centers with a cluster of servers are already common places in Internet to host large scale networking applications, which require huge amount of computation and storage resources. To keep up with the performance requirements of those applications, a data center has to accommodate a large number of servers. As Internet evolves and more diverse applications emerge, the computation and storage requirements for data centers grow quickly. However, using the conventional interconnection structure is hard to scale the number of servers in data centers. Hence, it is of importance to design new interconnection structures for future data centers in Internet. Four interesting topics are explored in this dissertation: (i) accommodating diverse commercial agreements in inter-domain routing, (ii) exploiting the Internet AS-level path diversity, (iii) supporting diverse network data planes, and (iv) diverse interconnection networks for data centers. The first part of this dissertation explores accommodating diverse commercial agreements in inter-domain routing while guaranteeing global routing convergence, so as to provide more path diversity in Internet. The second part of this dissertation studies exploiting the path diversity in Internet by running multiple routing processes in parallel, which compute multiple paths and those paths can complement each other in case one path has problems when dynamics present in the routing system. The third part of this dissertation studies supporting concurrent networks with heterogeneous data plane functions via network virtualization. Two virtual network platforms are presented, which achieve both high-speed packet forwarding in each virtual network and high degree of flexibility for each virtual network to customize its data plane functions. The last part of this dissertation presents a new scalable interconnection structure for data center networks. The salient feature of this new interconnection structure is that it expands to any number of servers without requiring to physically upgrading the existing servers.

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