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2001

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Articles 1711 - 1740 of 1858

Full-Text Articles in Engineering

Rad Module Infrastructure Of The Field-Programmable Port Extender (Fpx) Version 2.0, David E. Taylor, John W. Lockwood, Naji Naufel Jan 2001

Rad Module Infrastructure Of The Field-Programmable Port Extender (Fpx) Version 2.0, David E. Taylor, John W. Lockwood, Naji Naufel

All Computer Science and Engineering Research

The Field-programmable Port eXtender (FPX) provides dynamic, fast, and flexible mechanisms to process data streams at the ports of the Washington University Gigabit Switch (WUGS-20). In order to facilitate the design and implementation of portable hardware modules for the Reprogrammable Application Device (RAD) on the FPX board, infrastructure components have been developed. These components abstract application module designers from device-specific timing specifications of off-chip memory devices, as well as processing system-level control cells. This document describes the design and internal functionality of the infrastructure components and is intended as a reference for future component revisions and additions. Application module designers …

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The Fpx Kcpsm Module: An Embedded, Reconfigurable Active Processing Module For The Field Programmable Port Extender (Fpx), Henry Fu, John W. Lockwood Jan 2001

The Fpx Kcpsm Module: An Embedded, Reconfigurable Active Processing Module For The Field Programmable Port Extender (Fpx), Henry Fu, John W. Lockwood

All Computer Science and Engineering Research

While hardware plugins are well suited for processing data with high throughput, software plugins are well suited for implementing complex control functions. A plugin module has been implemented for the FPX that executes software on an embedded soft-core processor. By including this module in an FPX design, it is possible to implement active networking functions on the FPX using both hardware and software. The KCPSM, an 8-bit microcontroller developed by Xilinx Corp., has been embedded into an FPX module. The module includes circuits to be reprogrammed over the network and to execute new programs between the processing of data packerts. …

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Performance Of Deferred Reservations In Data Networks, Samphel Norden, Jonathan Turner Jan 2001

Performance Of Deferred Reservations In Data Networks, Samphel Norden, Jonathan Turner

All Computer Science and Engineering Research

This paper studies the performance of deferred resource reservation in data networks. Conventional resource reservation protocols, such as PNNI and RSVP adopt an all-or-nothing approach, where partially acquired resources must be released if resources are not available at all links on the chosen path. During periods of high network load, this leads users to retry requests repeatedly, adding control traffic at exactly the time when the network's capacity to process that control traffic is exhausted. Deferred REServation (DRES) can significantly improve performance by reducing the overall call rejection probability, allowing more traffic to be carried, using the same resources. Call …

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Generalized Rad Module Interface Specification Of The Field-Programmable Port Extender (Fpx) Version 2.0, David E. Taylor, John W. Lockwood, Sarang Dharmapurikar Jan 2001

Generalized Rad Module Interface Specification Of The Field-Programmable Port Extender (Fpx) Version 2.0, David E. Taylor, John W. Lockwood, Sarang Dharmapurikar

All Computer Science and Engineering Research

The Field-programmable Port eXtender (FPX) provides dynamic, fast, and flexible mechanisms to process data streams at the ports of the Washington University Gigabit Switch (WUGS-20). By performing all computations in FPGA hardware, cells and packets can be processed at the full line speed of the transmission interface, currently 2.4 Gbits/sec. In order to design and implement portable hardware modules for the Reprogrammable Application Devide (RAD) on the FPX board, all modules should conform to a standard interface. This standard interface specifies how modules receive and transmit ATM cells of data flows, prevent data loss during reconfiguration, and access off-chip memory. …

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An Efficient Quality Scalable Motion-Jpeg2000 Transmission Scheme, Ruibiao Qiu, Wei Yu Jan 2001

An Efficient Quality Scalable Motion-Jpeg2000 Transmission Scheme, Ruibiao Qiu, Wei Yu

All Computer Science and Engineering Research

Video application over the Internet are getting increasingly popular because of the explosive growth of the Internet. However, video packets loss due to network congestions can degrade the video quality substantially. In this paper, we propose a transmission scheme for Motion-JPEG2000. It can be implemented in an active network environment efficiently. Our simulation shows that our scheme gracefully adapts to network congestion and improves the quality of video transmission in congested IP networks.

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Placing Servers For Session-Oriented Services, Sumi Choi, Yuval Shavitt Jan 2001

Placing Servers For Session-Oriented Services, Sumi Choi, Yuval Shavitt

All Computer Science and Engineering Research

The provisioning of dynamic forms of services is becoming the main stream of today's network. In this paper, we focus on services assisted by network servers and different forms of associated sessions. We identify two types of services: transparent, where the session is unaware of the server location, and configurable, where the sessions need to be configured to use their closest server. For both types we formalize the problem of optimally placing network servers and introduce approximated solutions. We present simulation result of approximations and heuristics. We also solve the location problem optimally for a special topology. We show, through …

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Legends As A Device For Interacting With Visualizations, Mihail E. Tudoreanu, Eileen Kraemer Jan 2001

Legends As A Device For Interacting With Visualizations, Mihail E. Tudoreanu, Eileen Kraemer

All Computer Science and Engineering Research

Users and developers of visualization tools must deal with the problem of specifying what information to show and how to represent it. Typically, the user's focus of interest will change over time, and the specifications must change with the user's interests. Techniques for the simple, direct, and intuitive creation and refinement of these specifications can be useful. In this paper we show how legends, a natural element of graphical displays, may be used as a direct and unobstrusive interaction device through which users may interactively specify new visualizations and animations.

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The Smart Port Card: An Embedded Unix Processor Architecture For Network Management And Active Networking, John D. Dehart, William D. Richard, Edward W. Spitznagel, David E. Taylor Jan 2001

The Smart Port Card: An Embedded Unix Processor Architecture For Network Management And Active Networking, John D. Dehart, William D. Richard, Edward W. Spitznagel, David E. Taylor

All Computer Science and Engineering Research

This paper describes the architecture of the Smart Port Card (SPC) designed for use with the Washington University Gigabit Switch. The SPC uses an embedded Intel Pentium processor running open-source NetBSD to support network management and active networking applications. The SPC physically connects between a switch port and a normal link adapter, allowing cell streams to be processed as they enter or leave the switch. In addition to the hardware architecture, this paper describes current and future applications for the SPC.

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Services Provision In Ad Hoc Networks, Radu Handorean, Gruia-Catalin Roman Jan 2001

Services Provision In Ad Hoc Networks, Radu Handorean, Gruia-Catalin Roman

All Computer Science and Engineering Research

The client-server model continues to dominate distributed computing with increasingly more flexible variants being deployed. Many are centered on the notion of discovering services at run time and on allowing any system component to act as a service provider. The result is a growing reliance on the service registration and discovery mechanisms. This paper addresses the issue of facilitating such service provision capabilities in the presence of (logical and physical) mobility exhibited by applications executing over ad hoc networks. The solution being discussed entailes a new kind of service model, which we were able to build as an adaption layer …

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Meeting Research & Publication Requirements In An Undergraduate E T Program Through Senior Design Projects, Alok K. Verma Jan 2001

Meeting Research & Publication Requirements In An Undergraduate E T Program Through Senior Design Projects, Alok K. Verma

Engineering Technology Faculty Publications

(First paragraph) Success in an Engineering Technology programs has been traditionally evaluated based upon three factors namely, Teaching, Research and Service. While the relative ranking of these factors is arguable 1,5, it is the research (and the associated requirement of publication) which causes great anxiety for faculty in ET programs. This is specially true, in view of increasing emphasis placed on the research and publication by the ET programs in the nation. A number of articles have been written on the promotion and tenure requirements 2,3,4. Most of these publications discuss the general requirements of promotion and tenure and the …

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Combining Multiple Representations For Pen-Based Handwritten Digit Recognition, Fevzi̇ Ali̇moğlu, Ethem Alpaydin Jan 2001

Combining Multiple Representations For Pen-Based Handwritten Digit Recognition, Fevzi̇ Ali̇moğlu, Ethem Alpaydin

Turkish Journal of Electrical Engineering and Computer Sciences

We investigate techniques to combine multiple representations of a handwritten digit to increase classification accuracy without significantly increasing system complexity or recognition time. In pen-based recognition, the input is the dynamic movement of the pentip over the pressure sensitive tablet. There is also the image formed as a result of this movement. On a real-world database of handwritten digits containing more than 11,000 handwritten digits, we notice that the two multi-layer perceptron (MLP) based classifiers using these representations make errors on different patterns implying that a suitable combination of the two would lead to higher accuracy. We implement and compare …

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Meta-Genetic Programming: Co-Evolving The Operators Of Variation, Bruce Edmonds Jan 2001

Meta-Genetic Programming: Co-Evolving The Operators Of Variation, Bruce Edmonds

Turkish Journal of Electrical Engineering and Computer Sciences

The standard Genetic Programming approach is augmented by co-evolving the genetic operators. To do this the operators are coded as trees of indefinite length. In order for this technique to work, the language that the operators are defined in must be such that it preserves the variation in the base population. This technique can varied by adding further populations of operators and changing which populations act as operators for others, including itself, thus to provide a framework for a whole set of augmented GP techniques. The technique is tested on the parity problem. The pros and cons of the technique …

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Advances In Computer And Information Sciences: From Abacus To Holonic Agents, Tuncer Ören Jan 2001

Advances In Computer And Information Sciences: From Abacus To Holonic Agents, Tuncer Ören

Turkish Journal of Electrical Engineering and Computer Sciences

The shift of paradigm emphasizing the importance of the ability to process knowledge rather then being knowledgeable is stressed. A taxonomy of knowledge processing tools, machines, or systems is offered. Major possibilities for future achievements that the author would like to underline are listed with emphasis on agent technology, agent-directed simulation, holonic agents, holonic-agent simulation, and contribution of system theories for cognitive abilities such as understanding, learning, adaptation, and anticipation in computerization.

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Bag Distributed Real-Time Operating System And Task Migration, Beki̇r Tevfi̇k Akgün Jan 2001

Bag Distributed Real-Time Operating System And Task Migration, Beki̇r Tevfi̇k Akgün

Turkish Journal of Electrical Engineering and Computer Sciences

BAG is a distributed operating system designed for real-time applications which is run on a distributed real-time system. The heterogeneously distributed BAG system consists of nodes which have VME-bus chassis, different types of processor modules, and an interconnection network. The operating system has three main parts having distributed properties: task migration, load balancing and a distributed file system. Heterogeneous task migration is based on the extended finite state machine (EFSM) programming model. The EFMS model has also eased the implementation of the migration mechanism. The load balancing algorithm is centralized in one node. But the overall system will be a …

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All-Optical Networking, Altan Koçyi̇ği̇t, Demeter Gökişik, Semi̇h Bi̇lgen Jan 2001

All-Optical Networking, Altan Koçyi̇ği̇t, Demeter Gökişik, Semi̇h Bi̇lgen

Turkish Journal of Electrical Engineering and Computer Sciences

A survey of recent literature on all optical networking is presented. Starting from multiplexing techniques and topological features, network design and performance issues are reviewed. Particular attention is devoted to Wavelength Division Multiplexing (WDM) networks. Static and dynamic solutions of the routing and wavelength assignment (RWA) problem are considered. Issues of current research are summarized.

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Accurate Parameter Estimation For An Articulatory Speech Synthesizer With An Improved Neural Network Mapping, Hali̇s Altun, Tankut Yalçinöz, K. Mervyn Curtis Jan 2001

Accurate Parameter Estimation For An Articulatory Speech Synthesizer With An Improved Neural Network Mapping, Hali̇s Altun, Tankut Yalçinöz, K. Mervyn Curtis

Turkish Journal of Electrical Engineering and Computer Sciences

Neural network (NN) applications have recently been employed to extract the parameters of an articulatory speech synthesizer from a given speech signal. Results from these attempts showed that a single NN is insufficient to cover all of the possible configurations uniquely. Moreover, apart from their computational advantages, NN mapping is so far not superior to the other mapping techniques [1]. Thus there is a clear need to improve NN solution to the inverse problem. Results from our earlier experiments with an articulatory speech synthesizer have shown that the statistical characteristic of the articulatory target pattern vectors can be exploited for …

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Performance Evaluation Of Safer K-64 And S-Boxes Of The Safer Family, Ekrem Aras, Melek D. Yücel Jan 2001

Performance Evaluation Of Safer K-64 And S-Boxes Of The Safer Family, Ekrem Aras, Melek D. Yücel

Turkish Journal of Electrical Engineering and Computer Sciences

If the characteristics of s-boxes of the SAFER family of ciphers are examined for the criteria of strict avalanche, bit independence, and XOR table distribution, experiments show that the ``exponentiating'' s-box has a weakness for an input difference of 128 (=10000000_{2}) and the ``logarithm-taking'' s-box has a weakness for an input difference of 253 (=11111101_{2}). However, since these experiments are performed by isolating the s-boxes from the general structure, they do not necessarily indicate a weakness in the overall algorithm. We propose a quick and rough test method, called the avalanche weight distribution criterion, to evaluate the overall performance of …

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Virtual Path Bandwidth Distribution And Capacity Allocation With Bandwidth Sharing, Karen Marie Anewalt Jan 2001

Virtual Path Bandwidth Distribution And Capacity Allocation With Bandwidth Sharing, Karen Marie Anewalt

Dissertations, Theses, and Masters Projects

Broadband high-speed networks, such as B-ISDN, are expected to play a dominant role in the future of networking due to their capability to service a variety of traffic types with very different bandwidth requirements such as video, voice and data. to increase network efficiency in B-ISDN and other such connection oriented networks, the concept of a virtual path (VP) has been proposed and studied in the literature. A VP is a permanent or semi-permanent reservation of capacity between two nodes. Using VPs can potentially reduce call setup delays, simplify hardware, provide quality of service performance guarantees, and reduce disruption in …

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Ultrasonographic Measurement Of Periodontal Attachment Levels, John Edward Lynch Jan 2001

Ultrasonographic Measurement Of Periodontal Attachment Levels, John Edward Lynch

Dissertations, Theses, and Masters Projects

Periodontal disease is one of the two major causes of tooth loss today, and has been associated with several systemic diseases, such as diabetes, cardiovascular disease, stroke, and adverse pregnancy outcomes. Unfortunately, the most widely used diagnostic tool for assessment of periodontal diseases, measurement of periodontal attachment loss with a manual probe, may overestimate attachment loss by as much as 2mm in untreated sites, while underestimating attachment loss by an even greater margin following treatment. Manual probing is also invasive, which causes patient discomfort.;This work describes the development and testing of an ultrasonographic periodontal probe designed to replace manual probing. …

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Advantages Of Using Fuzzy Class Memberships In Self-Organizing Map And Support Vector Machines, Sunghwan Sohn, Cihan H. Dagli Jan 2001

Advantages Of Using Fuzzy Class Memberships In Self-Organizing Map And Support Vector Machines, Sunghwan Sohn, Cihan H. Dagli

Engineering Management and Systems Engineering Faculty Research & Creative Works

The self-organizing map (SOM) is naturally unsupervised learning, but if a class label is known, it can be used as the classifier. In a SOM classifier, each neuron is assigned a class label based on the maximum class frequency and classified by a nearest neighbor strategy. The drawback when using this strategy is that each pattern is treated by equal importance in counting class frequency regardless of its typicalness. For this reason, the fuzzy class membership can be used instead of crisp class frequency and this fuzzy membership-label neuron provides another perspective of a feature map. This fuzzy class membership …

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Evolution Of The Resonance And Incommensurate Spin Fluctuations In Superconducting Yba₂Cu₃O₆₊ₓ, Pengcheng Dai, Herbert A. Mook, Rodney Dale Hunt, Fatih Dogan Jan 2001

Evolution Of The Resonance And Incommensurate Spin Fluctuations In Superconducting Yba₂Cu₃O₆₊ₓ, Pengcheng Dai, Herbert A. Mook, Rodney Dale Hunt, Fatih Dogan

Materials Science and Engineering Faculty Research & Creative Works

Polarized and unpolarized neutron triple-axis spectrometry was used to study the dynamical magnetic susceptibility Χ″(q, ω) as a function of energy (ℏ ω) and wave vector (q) in a wide temperature range for the bilayer superconductor YBa2Cu3O6+x with oxygen concentrations, x, of 0.45, 0.5, 0.6, 0.7, 0.8, 0.93, and 0.95. The most prominent features in the magnetic spectra include a spin gap in the superconducting state, a pseudogap in the normal state, the much-discussed resonance, and incommensurate spin fluctuations below the resonance. We establish the doping dependence of the spin gap in the superconducting state, …

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Dynamic Re-Optimization Of A Fed-Batch Fermentor Using Adaptive Critic Designs, Donald C. Wunsch, M. S. Iyer Jan 2001

Dynamic Re-Optimization Of A Fed-Batch Fermentor Using Adaptive Critic Designs, Donald C. Wunsch, M. S. Iyer

Electrical and Computer Engineering Faculty Research & Creative Works

Traditionally, fed-batch biochemical process optimization and control uses complicated off-line optimizers, with no online model adaptation or re-optimization. This study demonstrates the applicability of a class of adaptive critic designs for online re-optimization and control of an aerobic fed-batch fermentor. Specifically, the performance of an entire class of adaptive critic designs, viz., heuristic dynamic programming, dual heuristic programming and generalized dual heuristic programming, was demonstrated to be superior to that of a heuristic random optimizer, on optimization of a fed-batch fermentor operation producing monoclonal antibodies

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High-Power Microwave Wideband Random Signal Measurement And Narrowband Signal Detection Against The Noise Background, Marina Koledintseva, Alexander A. Kitaytsev, V. A. Konkin Jan 2001

High-Power Microwave Wideband Random Signal Measurement And Narrowband Signal Detection Against The Noise Background, Marina Koledintseva, Alexander A. Kitaytsev, V. A. Konkin

Electrical and Computer Engineering Faculty Research & Creative Works

A method of both measurement of power parameters of a microwave wideband intense random signal and detection of a narrow-band signal with unknown frequency and power against a background of this wideband signal is presented. This method is based on nonheterodyne frequency and power conversion using a gyromagnetic converter that operates in two regimes: resonance detection and cross-multiplication. The wideband spectrum envelope of a random signal is visualized, and by switching two regimes and using correspondent filtration of the converted RF signal, the narrowband signals can be detected and measured. The block-scheme and operation of a two-channel measuring device combining …

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Reduced Parts-Count Multi-Level Rectifiers, Keith Corzine, J. Yuen, J. R. Baker Jan 2001

Reduced Parts-Count Multi-Level Rectifiers, Keith Corzine, J. Yuen, J. R. Baker

Electrical and Computer Engineering Faculty Research & Creative Works

Multi-level power converters have gained much attention due to their high power quality, low switching losses, and high-voltage capability. These advantages make the multi-level converter a candidate topology for the next generation of naval ship propulsion systems. The primary disadvantage of these systems is the large number of semiconductors involved. This paper presents a reduced parts-count rectifier which is well suited for naval rectifier applications where bi-directional power flow is not required. The proposed converter is analyzed and experimentally verified on an 18 kW four-level rectifier/inverter system.

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Millimeter Wave Oscillator Based Dielectric Hemisphere With Cylinder Shield, Sergey Kharkovsky, A. E. Kogut, V. V. Kutuzov Jan 2001

Millimeter Wave Oscillator Based Dielectric Hemisphere With Cylinder Shield, Sergey Kharkovsky, A. E. Kogut, V. V. Kutuzov

Electrical and Computer Engineering Faculty Research & Creative Works

The purpose of this paper is the investigation of the main Gunn diode oscillator characteristics with a hemispherical dielectric resonator which is shielded by a metal cylinder. The frequency, output power and electronic tuning of frequency, the steepness of which allows one to estimate the frequency stability in relation to the parasitic change of the Gunn diode voltage, and their comparative analysis with the characteristics of generation in a similar open dielectric resonator.

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A Fast Evanescent Wave Algorithm, W. C. Chew, L. (Lijun) J. Jiang, S. Velamparambil Jan 2001

A Fast Evanescent Wave Algorithm, W. C. Chew, L. (Lijun) J. Jiang, S. Velamparambil

Electrical and Computer Engineering Faculty Research & Creative Works

Description of a fast evanescent wave algorithm was presented that traded off the use of memory for increasing the speed. The use of the buffer boxes was avoided by the algorithm which increased its speed. An efficient method to derive or store the evanescent wave spectrum from the propagating wave spectrum was studied.

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Power Quality, Badrul H. Chowdhury Jan 2001

Power Quality, Badrul H. Chowdhury

Electrical and Computer Engineering Faculty Research & Creative Works

One big reason for the poor power quality incidents experienced today is the proliferation of electronic devices. A voracious appetite for higher efficiency and productivity in the manufacturing sector, comfort and automation in homes, and efficient lighting systems in commercial installations are driving the market for power electronic devices. At the forefront of this explosion is the switched power supply. Compared to its predecessor-the linear power supply-it can convert higher power much more efficiently and with a significantly smaller footprint. The switched power supply is found in most of today''s computers, fax machines, laser printers, office copiers, etc.

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An Integrated Design-Object Modeling Environment -- Pluggable Metamodel Mechanism --, Masaharu Yoshioka, Takayuki Sekiya, Tetsuo Tomiyama Jan 2001

An Integrated Design-Object Modeling Environment -- Pluggable Metamodel Mechanism --, Masaharu Yoshioka, Takayuki Sekiya, Tetsuo Tomiyama

Turkish Journal of Electrical Engineering and Computer Sciences

We propose a new integrated computational environment to support design object modeling, during engineering design process that requires a variety of design object models, such as a geometric model, a control model, and a finite element model. To integrate multiple design object models, we have developed a mechanism called a metamodel mechanism that maintains consistency among various models. The metamodel mechanism represents relationships among concepts used in these models and is useful, for example, to conduct concurrent engineering practices. In this framework, we formalize a design process as operations to the metamodel. This paper expands the concept of the metamodel …

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Avalanche And Bit Independence Properties For The Ensembles Of Randomly Chosen N \Times N S-Boxes, Işil Vergi̇li̇, Melek D. Yücel Jan 2001

Avalanche And Bit Independence Properties For The Ensembles Of Randomly Chosen N \Times N S-Boxes, Işil Vergi̇li̇, Melek D. Yücel

Turkish Journal of Electrical Engineering and Computer Sciences

Cryptographic test methods such as avalanche, strict avalanche and bit independence criteria, which measure the degree of security of the s-boxes of substitution-permutation networks, are applied to randomly generated ensembles of ( n \times n \) s-boxes. Statistical analysis of experimental data directs the work towards defining ``relative errors'' and examining the avalanche and strict avalanche criteria within ``relative error ranges''. Histograms of relative errors in each ensemble are evaluated, and combining the results of different ensembles corresponding to different values of the s-box size, variations of maximum relative errors versus the size of the s-box are depicted. Some predictions …

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A More Efficient Design And Implementation Of Cal Programs In Natural Science Using Object-Oriented Technology, Jurgen Friedrich Jan 2001

A More Efficient Design And Implementation Of Cal Programs In Natural Science Using Object-Oriented Technology, Jurgen Friedrich

Turkish Journal of Electrical Engineering and Computer Sciences

With the amount and complexity of science topics and applications increasing, the need for appropriate and effective science education is constantly growing. Computer-based education is very promising to help both teachers and learners in their difficult task, which involves complex psychological processes. This complexity is reflected in high demands on the design and implementation methods used to create computer-assisted learning (CAL) programs. Due to their concepts, flexibility, maintainability and extended library resources, object-oriented technology (OOT) is very suitable to producing this type of pedagogical tool. The introduced approach is demonstrated by a basketball simulation program for instruction in Newtonian mechanics …

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