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Designing A Data Warehouse For Cyber Crimes, Il-Yeol Song, John D. Maguire, Ki Jung Lee, Namyoun Choi, Xiaohua Hu, Peter Chen Jan 2006

Designing A Data Warehouse For Cyber Crimes, Il-Yeol Song, John D. Maguire, Ki Jung Lee, Namyoun Choi, Xiaohua Hu, Peter Chen

Journal of Digital Forensics, Security and Law

One of the greatest challenges facing modern society is the rising tide of cyber crimes. These crimes, since they rarely fit the model of conventional crimes, are difficult to investigate, hard to analyze, and difficult to prosecute. Collecting data in a unified framework is a mandatory step that will assist the investigator in sorting through the mountains of data. In this paper, we explore designing a dimensional model for a data warehouse that can be used in analyzing cyber crime data. We also present some interesting queries and the types of cyber crime analyses that can be performed based on …


Conducting Business In Network Centric Collaborative Environments, Vance Saunders, Paul Bailor, Charles Cohen, Ann K. Miller, Barbra Sorensen Dec 2005

Conducting Business In Network Centric Collaborative Environments, Vance Saunders, Paul Bailor, Charles Cohen, Ann K. Miller, Barbra Sorensen

Electrical and Computer Engineering Faculty Research & Creative Works

The development of the World Wide Web (or Internet) has provided the ability to connect the entire world together. Thousands of web servers located around the world allow users to connect and communicate with one another. Additionally, a huge transaction-based product sales business has evolved, via the Internet. for many, the next generation of the Internet needs to focus on collections of servers and users working collectively together to solve problems. Grids and the Global Information Grid (GIG) are terms associated with enabling technologies that provide the framework for collections of servers and users to work together. Network Centric Operations …


Robust Video Transmission Based On Multiple Description Scalable Coding With Erec, Haifeng Zheng, Lun Yu, Chang Wen Chen Jan 2005

Robust Video Transmission Based On Multiple Description Scalable Coding With Erec, Haifeng Zheng, Lun Yu, Chang Wen Chen

Electrical Engineering and Computer Science Faculty Publications

This paper presents a multiple description scalable video coding scheme based on overcomplete motion compensated temporal filtering, named MD-OMCTF, for robust video transmission over wireless and packet loss networks. The intrinsic nature of the structure of OMCTF and embedded coding with modified SPIHT algorithm enable us to provide fully scalable properties for the proposed scheme. We show that multiple description coding is very effective in combating with channel failures in both Internet and wireless video. The integration of MD with OMCTF allows us to achieve both loss resilience and complete scalability. In order to further improve error-resilience to channel bit …


Multiple Description Distributed Image Coding With Side Information For Mobile Wireless Transmission, Min Wu, Daewon Song, Chang Wen Chen Jan 2005

Multiple Description Distributed Image Coding With Side Information For Mobile Wireless Transmission, Min Wu, Daewon Song, Chang Wen Chen

Electrical Engineering and Computer Science Faculty Publications

Multiple description coding (MDC) is a source coding technique that involves coding the source information into multiple descriptions, and then transmitting them over different channels in packet network or error-prone wireless environment to achieve graceful degradation if parts of descriptions are lost at the receiver. In this paper, we proposed a multiple description distributed wavelet zero tree image coding system for mobile wireless transmission. We provide two innovations to achieve an excellent error resilient capability. First, when MDC is applied to wavelet subband based image coding, it is possible to introduce correlation between the descriptions in each subband. We consider …


Constant Quality Constrained Bit Allocation For Leaky Prediction Based Fgs Video Streaming, Jianhua Wu, Jianfei Cai, Chang Wen Chen Jan 2005

Constant Quality Constrained Bit Allocation For Leaky Prediction Based Fgs Video Streaming, Jianhua Wu, Jianfei Cai, Chang Wen Chen

Electrical Engineering and Computer Science Faculty Publications

Leaky prediction based FGS (Fine Granularity Scalability) can achieve better coding efficiency than the baseline FGS. However, for leaky prediction based FGS (L-FGS), constant quality constrained bit allocation, i.e., how to optimally allocate bits given the current channel bandwidth, is still an open problem. In this paper, based on the accurate R-D (Rate-Distortion) model developed in our previous work, we propose a constant quality constrained bit allocation scheme for L-FGS. The proposed scheme is a combination of offline and online processes. During the offline stage, we perform the L-FGS encoding and collect the necessary feature information. At the online stage, …


Multiple Wavelet-Tree-Based Image Coding And Robust Transmission, Lei Cao, Chang Wen Chen Oct 2004

Multiple Wavelet-Tree-Based Image Coding And Robust Transmission, Lei Cao, Chang Wen Chen

Electrical Engineering and Computer Science Faculty Publications

In this paper, we present techniques based on multiple wavelet-tree coding for robust image transmission. The algorithm of set partitioning in hierarchical trees (SPIHT) is a state-of-the-art technique for image compression. This variable length coding (VLC) technique, however, is extremely sensitive to channel errors. To improve the error resilience capability and in the meantime to keep the high source coding efficiency through VLC, we propose to encode each wavelet tree or a group of wavelet trees using SPIHT algorithm independently. Instead of encoding the entire image as one bitstream, multiple bitstreams are generated. Therefore, error propagation is limited within individual …


Effective Quality Analysis For Video Streaming Over Wireless Ad Hoc Network, Zhihai He, Chang Wen Chen Jan 2004

Effective Quality Analysis For Video Streaming Over Wireless Ad Hoc Network, Zhihai He, Chang Wen Chen

Electrical Engineering and Computer Science Faculty Publications

Video encoding and streaming over wireless ad hoc network operates under severe conditions, such as time-varying channel characteristics with bursty errors, limit power for data transmission, and dynamic topology of the self-organized network, stringent time delay for packet delivery, etc. Due to the dynamic topology, complex mechanism, and time-varying nature of the wireless ad hoc network, the network system and the streaming service often exhibit unpredictable behaviors. The ultimate goal in the wireless video streaming service is to provide the end user with the best possible video presentation quality. The video streaming quality, often measured by the end-to-end picture distortion, …


Collaborative Image Transmission Over Wireless Sensor Networks, Min Wu, Chang Wen Chen Jan 2004

Collaborative Image Transmission Over Wireless Sensor Networks, Min Wu, Chang Wen Chen

Electrical Engineering and Computer Science Faculty Publications

The imaging sensors are able to provide intuitive visual information for quick recognition and decision. However, imaging sensors usually generate vast amount of data. Thus, processing of image data collected in the sensor network for the purpose of energy efficient transmission poses a significant technical challenge. In particular, when a cluster of imaging sensors is activated to track certain moving target, multiple sensors may be collecting similar visual information simultaneously. With correlated image data, we need to intelligently reduce the redundancy among the neighboring sensors so as to minimize the energy for transmission, the primary source of sensor energy consumption. …


A Half D1 Mpeg-4 Encoder On The Bsp-15 Dsp, Lulin Chen, Zhihai He, Chang Wen Chen, Michael A. Isnardi Jan 2004

A Half D1 Mpeg-4 Encoder On The Bsp-15 Dsp, Lulin Chen, Zhihai He, Chang Wen Chen, Michael A. Isnardi

Electrical Engineering and Computer Science Faculty Publications

In this paper, we present the work on implementation of a half-Dl interlaced MPEG-4 encoder with Equator Technology DSP chip, BSP-15. The BSP-15 DSP consists mainly of a VLIW core, Co-processors, and media I/O interfaces. The encoder utilizes several BSP-15 functional blocks in parallel. In general, the VLIW performs pixel processing that is computationally intensive. The VLx coprocessor completes variable length coding. Further parallelism is obtained by pre-loading data cache and doubling data buffers. Given the DSP processing power and real time requirements, a complexity control scheme is implemented. A frame-level quantization scheme with quality and rate control is employed. …


Layered Unequal Loss Protection For Progressive Image Transmission Over Packet Loss Channels, Jianfei Cai, Xiangjun Li, Chang Wen Chen Jan 2004

Layered Unequal Loss Protection For Progressive Image Transmission Over Packet Loss Channels, Jianfei Cai, Xiangjun Li, Chang Wen Chen

Electrical Engineering and Computer Science Faculty Publications

In the past, many schemes have been proposed for progressive image transmission using unequal error protection (UEP) or unequal loss protection (ULP). However, most existing UEP/ULP schemes do not consider the minimum image quality requirement and usually have high computation complexity. In this paper, we propose a layered ULP (L-ULP) scheme for progressive image transmission over packet loss channels, which is able to solve the mentioned problems of existing ULP schemes by smartly choosing the layers. The numerical results show that the proposed L-ULP scheme is quite promising for fast image transmission over packet loss networks.


Robust And Efficient Video/Image Transmission, Xi Min Zhang Jan 2003

Robust And Efficient Video/Image Transmission, Xi Min Zhang

Dissertations

The Internet has become a primary medium for information transmission. The unreliability of channel conditions, limited channel bandwidth and explosive growth of information transmission requests, however, hinder its further development. Hence, research on robust and efficient delivery of video/image content is demanding nowadays.

Three aspects of this task, error burst correction, efficient rate allocation and random error protection are investigated in this dissertation. A novel technique, called successive packing, is proposed for combating multi-dimensional (M-D) bursts of errors. A new concept of basis interleaving array is introduced. By combining different basis arrays, effective M-D interleaving can be realized. It has …


Rate-Based End-To-End Congestion Control Of Multimedia Traffic In Packet Switched Networks, Mingsheng Peng, S. R. Subramanya, Jagannathan Sarangapani Jan 2003

Rate-Based End-To-End Congestion Control Of Multimedia Traffic In Packet Switched Networks, Mingsheng Peng, S. R. Subramanya, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposes an explicit rate-based end-to-end congestion control mechanism to alleviate congestion of multimedia traffic in packet switched networks such as the Internet. The congestion is controlled by adjusting the transmission rates of the sources in response to the feedback information from destination such as the buffer occupancy, packet arrival rate and service rate at the outgoing link, so that a desired quality of service (QoS) can be met. The QoS is defined in terms of packet loss ratio, transmission delay, power, and network utilization. Comparison studies demonstrate the effectiveness of the proposed scheme over New-Reno TCP (a variant …


Projection-Based Image Registration In The Presence Of Fixed-Pattern Noise, Ernest Armstrong, Stephen C. Cain, Majeed M. Hayat Dec 2001

Projection-Based Image Registration In The Presence Of Fixed-Pattern Noise, Ernest Armstrong, Stephen C. Cain, Majeed M. Hayat

Electrical and Computer Engineering Faculty Research and Publications

A computationally efficient method for image registration is investigated that can achieve an improved performance over the traditional two-dimensional (2-D) cross-correlation-based techniques in the presence of both fixed-pattern and temporal noise. The method relies on transforming each image in the sequence of frames into two vector projections formed by accumulating pixel values along the rows and columns of the image. The vector projections corresponding to successive frames are in turn used to estimate the individual horizontal and vertical components of the shift by means of a one-dimensional (1-D) cross-correlation-based estimator. While gradient-based shift estimation techniques are computationally efficient, they often …


Collaborative Distance Education In Power Engineering, Anil Pahwa, Shelli K. Starrett, Kraig J. Olejniczak, S. D. Sudhoff, Mariesa Crow Feb 2000

Collaborative Distance Education In Power Engineering, Anil Pahwa, Shelli K. Starrett, Kraig J. Olejniczak, S. D. Sudhoff, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a perspective on offering "shared-courses," or courses simultaneously offered at two or more universities via various distance educational frameworks. Over a three year duration, two senior/graduate level courses were jointly developed and offered to the students at the University of Missouri--Rolla, the University of Arkansas, Kansas State University, and Purdue University. This paper discusses the various distance educational technologies including two-way audio/visual via ISDN line, video-tapes, and web-based conferencing. Both instructor and student reactions to these mediums are included. Pedagogical methods appropriate for these mediums are outlined. The paper concludes with recommendations and strategies for engineering institutions …


Comprehensive Analysis Of Edge Detection In Color Image Processing, Shu-Yu Zhu, Konstantinos N. Kostas Plataniotis, Anastasios N. Venetsanopoulos Apr 1999

Comprehensive Analysis Of Edge Detection In Color Image Processing, Shu-Yu Zhu, Konstantinos N. Kostas Plataniotis, Anastasios N. Venetsanopoulos

Electrical Engineering and Computer Science Faculty Publications

Various approaches to edge detection for color images, including techniques extended from monochrome edge detection as well as vector space approaches, are examined. In particular, edge detection techniques based on vector order statistic operators and difference vector operators are studied in detail. Numerous edge detectors are obtained as special cases of these two classes of operators. The effect of distance measures on the performance of different color edge detectors is studied by employing distance measures other than the Euclidean norm. Variations are introduced to both the vector order statistic operators and the difference vector operators to improve noise performance. They …


Understanding Comics: The Invisible Art, Alan D. Manning Mar 1998

Understanding Comics: The Invisible Art, Alan D. Manning

Faculty Publications

INSIGHTS about professional communication may come from odd and unexpected places. McCloud's Understanding Comics (hereafter UC) is a case in point. Despite the juvenile connotations evoked by any discussion of comic books, the theory of visual communication presented in UC arguably rivals the best of contemporary semiotics (that is, the study of how we make meaning out of gestures, words, paragraphs, pictures, and so on).


Signal Injection With Perceptual Criteria, T. Engi̇n Tuncer Jan 1998

Signal Injection With Perceptual Criteria, T. Engi̇n Tuncer

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a novel method for increasing the coding performance and information transmission capacity is presented. This method is mainly based on perceptual modelling of input signal such as speech or audio. Presented approach may be seen as an alternative to transforms which dynamically change analysis window for better energy compaction. A perceptual model is established in order to obtain a global masking threshold in frequency below which sounds become inaudible. Certain criteria are developed for identifying the signal injection bands. A new multiband filter design method which is a generalization of windowing method is used to separate the …


Block-Based Hybrid Video Coding Using Motion-Compensated Long-Term Memory Prediction, Thomas Wiegand, Xiaozheng Zhang, Bernd Girod Sep 1997

Block-Based Hybrid Video Coding Using Motion-Compensated Long-Term Memory Prediction, Thomas Wiegand, Xiaozheng Zhang, Bernd Girod

Electrical Engineering

Our new approach extends the spatial displacement vector utilized in block-based hybrid video coding by a variable time delay permitting the use of more frames than the previously decoded one for motion compensation. The longterm memory covers the decoded frames of some seconds at the encoder's as well as the decoder's side. This scheme is well suited in cases of repetition in the sequence, e.g. a head is rotating back into its old position, or if the camera is shaking. However, transmission of the variable time delay requires additional bit-rate which may be prohibitive when the size of the long-term …


Motion Compensation And Very Low Bit Rate Video Coding, Shu Lin May 1997

Motion Compensation And Very Low Bit Rate Video Coding, Shu Lin

Dissertations

Recently, many activities of the International Telecommunication Union (ITU) and the International Standard Organization (ISO) are leading to define new standards for very low bit-rate video coding, such as H.263 and MPEG-4 after successful applications of the international standards H.261 and MPEG-1/2 for video coding above 64kbps. However, at very low bit-rate the classic block matching based DCT video coding scheme suffers seriously from blocking artifacts which degrade the quality of reconstructed video frames considerably. To solve this problem, a new technique in which motion compensation is based on dense motion field is presented in this dissertation.

Four efficient new …


Application Of Inversions To Lossless Image Compression, Ziya Arnavut Nov 1996

Application Of Inversions To Lossless Image Compression, Ziya Arnavut

Department of Electrical and Computer Engineering: Faculty Publications

Linear prediction schemes, such as that of the Joint Photographic Experts Group (JPEG), are simple and normally produces a residual sequence with lower zero-order entropy. Occasionally the entropy of the prediction error becomes greater than that of the original image. Such situations frequently occur when the image data have discrete gray levels located within certain intervals. To alleviate this problem, various authors have suggested different preprocessing methods. However, the techniques reported require two passes. We extend the definition of Lehmer-type inversions (Lehmer 1960 and 1964) from permutations to multiset permutations and present a one-pass algorithm based on inversions of a …


Motion Estimation And Video Coding, Xiaochun Xia Oct 1996

Motion Estimation And Video Coding, Xiaochun Xia

Dissertations

Over the last ten years. research on the analysis of visual motion has come to play a key role in the fields of data compression for visual communication as well as computer vision. Enormous efforts have been made on the design of various motion estimation algorithms.

One of the fundamental tasks in motion estimation is the accurate measurement of 2-D dense motion fields. For this purpose. we devise and present in this dissertation a multiattribute feedback computational framework. In this framework for each pixel in an image. instead of a single image intensity. multiple image attributes are computed as conservation …


On Optimal Design And Applications Of Linear Transforms, Mehmet V. Tazebay Jan 1996

On Optimal Design And Applications Of Linear Transforms, Mehmet V. Tazebay

Dissertations

Linear transforms are encountered in many fields of applied science and engineering. In the past, conventional block transforms provided acceptable answers to different practical problems. But now, under increasing competitive pressures, with the growing reservoir of theory and a corresponding development of computing facilities, a real demand has been created for methods that systematically improve performance. As a result the past two decades have seen the explosive growth of a class of linear transform theory known as multiresolution signal decomposition. The goal of this work is to design and apply these advanced signal processing techniques to several different problems.

The …


Theory, Design And Applications Of Linear Transforms For Information Transmission, Adil Benyassine Jan 1995

Theory, Design And Applications Of Linear Transforms For Information Transmission, Adil Benyassine

Dissertations

The aim of this dissertation is to study the common features of block transforms, subband filter banks, and wavelets, and demonstrate how discrete uncertainty can be applied to evaluate these different decomposition techniques. In particular, we derive an uncertainty bound for discrete-time functions. It is shown that this bound is the same as that for continuous-time functions, if the discrete-time functions have a certain degree of regularity.

This dissertation also deals with spectral modeling in filter banks. It is shown, both theoretically and experimentally, that subspectral modeling is superior to full spectrum modeling if performed before the rate change. The …


Scheduling Of Flexible Manufacturing Systems With Automated Guided Vehicles Using Petri Net Models, Hua-Sheng Chiu Jan 1995

Scheduling Of Flexible Manufacturing Systems With Automated Guided Vehicles Using Petri Net Models, Hua-Sheng Chiu

Theses

In this thesis, Petri net models for Flexible Manufacturing Systems (EMS) are constructed. A firing sequence of the Petri net from the initial marking to the final marking can be seen as a schedule of the modeled FMS. By using the branch-and-bound algorithm, an optimal schedule of the FMS can be obtained.

Automated Guided Vehicle Systems (AGVS) are increasingly used for material handling in factories and warehouses. An AGVS can reduce labor costs and is ready to be integrated into an automated factory. This thesis presents two AGVS models (shared and duty) which integrate the control of AGVS with the …


Performance Analysis Of The "Fiber Distributed Data Interface (Fddi) Network" Using Petri Nets And Spnp Software Package, Savvas Eteoclis Christodoulou May 1994

Performance Analysis Of The "Fiber Distributed Data Interface (Fddi) Network" Using Petri Nets And Spnp Software Package, Savvas Eteoclis Christodoulou

Theses

The main purpose of this thesis is to model a "Fiber Distributed Data Interface" (FDDI) Network using Petri Nets, and to analyze its performance with the help of the SPNP software package. The verification of a communication protocol, by modeling it as a discrete-event system using Petri Nets is a new approach.

The correlation between the throughput rate, voice and data throughput, and the parameters of the system, such as the network load and the network speed are investigated. An overview of the "Fiber Distributed Data Interface" is provided, along with its network protocol and the limitations of its operating …


Object Oriented Design Of Petri Net Simulator, Himanshu Juneja Oct 1993

Object Oriented Design Of Petri Net Simulator, Himanshu Juneja

Theses

Petri nets are highly useful for modeling discrete event dynamic systems. The objective of this effort is to develop a tool for drawing, editing and simulating Petri nets using object oriented programming on a standard platform. The object oriented approach was chosen because of its code reuse and extendability features which simplify the task of adding features to the tool as the model evolves. The design stresses on modeling of the problem by objects which closely relate the system design with the implementation.

C++ is used for implementing the object oriented design, and the XView toolkit is used for building …


Reduced Bandwidth For Remote Vehicle Operations, Timothy E. Noell, Fred W. Depiero Jun 1993

Reduced Bandwidth For Remote Vehicle Operations, Timothy E. Noell, Fred W. Depiero

Electrical Engineering

Oak Ridge National Laboratory staff have developed a video compression system for low-bandwidth remote operations. The objective is to provide real-time video at data rates comparable to available tactical radio links, typically 16 to 64 thousand bits per second (kbps), while maintaining sufficient quality to achieve mission objectives. The system supports both continuous lossy transmission of black and white (gray scale) video for remote driving and progressive lossless transmission of black and white images for remote automatic target acquisition. The average data rate of the resulting bit stream is 64 kbps. This system has been demonstrated to provide video of …


Modeling And Analysis Of Semiconductor Manufacturing Processes Using Petri Nets, Xinyao Wang May 1993

Modeling And Analysis Of Semiconductor Manufacturing Processes Using Petri Nets, Xinyao Wang

Theses

This thesis addresses the issues in modeling and analysis of multichip module (MCM) manufacturing processes using Petri nets. Building such graphical and mathematical models is a crucial step to understand MCM technologies and to enhance their application scope.

In this thesis, the application of Petri nets is presented with top-down and bottom-up approaches. The theory of Petri nets is summarized with its basic notations and properties at first. After that, the capability of calculating and analyzing Petri nets with deterministic timing information is extended to meet the requirements of the MCM models. Then, using top-down refining and system decomposition, MCM …


Face Recognition With Neural Networks, Dennis L. Krepp Dec 1992

Face Recognition With Neural Networks, Dennis L. Krepp

Theses and Dissertations

This study investigated neural networks for face verification and classification. The research concentrated on developing a neural network based feature extractor and/or classifier to perform authorized user verification in a realistic work environment. Recognition accuracy, system assumptions, training time, and execution time were analyzed to determine the feasibility of a neural network approach. Data was collected using a camcorder and two segmentation schemes: manual segmentation and motion-based, automatic segmentation. Data consisted of over 2000. 32x32 pixel, 8 bit gray scale images of 52 subjects; each subject had two to ten days worth of images collected. Several training and test sets …


Remote Driving With Reduced Bandwidth Communication, Fred W. Depiero, Timothy E. Noell, Timothy F. Gee Aug 1992

Remote Driving With Reduced Bandwidth Communication, Fred W. Depiero, Timothy E. Noell, Timothy F. Gee

Electrical Engineering

Oak Ridge National Laboratory has developed a real-time video transmission system for low-bandwidth remote operations. The system supports both continuous transmission of video for remote driving and progressive transmission of still images. Inherent in the system design is a spatiotemporal limitation to the effects of channel errors. The average data rate of the system is 64,000 bits/s, a compression of approximately 1000:1 for the black and white National Television Standard Code video. The image quality of the transmissions is maintained at a level that supports teleoperation of a high-mobility multipurpose wheeled vehicle at speeds up to 15 mph on a …