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- Title
- A connected dominating-set-based routing in ad hoc wireless networks.
- Creator
- Gao, Ming., Florida Atlantic University, Wu, Jie
- Abstract/Description
-
In ad hoc wireless networks, routing protocols are challenged with establishing and maintaining multihop routes in the face of mobility, bandwidth limitation and power constraints. Routing based on a connected dominating set is a promising approach, where the searching space for a router reduced to nodes in the set. A set is dominating if all the nodes in the system are either in the dominating set or adjacent to some nodes in the dominating set. In this thesis, we propose a method of...
Show moreIn ad hoc wireless networks, routing protocols are challenged with establishing and maintaining multihop routes in the face of mobility, bandwidth limitation and power constraints. Routing based on a connected dominating set is a promising approach, where the searching space for a router reduced to nodes in the set. A set is dominating if all the nodes in the system are either in the dominating set or adjacent to some nodes in the dominating set. In this thesis, we propose a method of calculating power-aware connected dominating set. Our simulation results show that the proposed approach outperforms several existing approaches in terms of life span of the network. We also discuss mobility management in dominating-set-based networks. Three operations are considered which are mobile host switch on, mobile host switch off and mobile host movement. We also discuss the use of dynamic source routing as an application of the connected dominating set.
Show less - Date Issued
- 2001
- PURL
- http://purl.flvc.org/fcla/dt/12780
- Subject Headings
- Mobile computing, Computer networks, Computer algorithms
- Format
- Document (PDF)
- Title
- Routing in mobile ad-hoc wireless networks.
- Creator
- Li, Hailan., Florida Atlantic University, Wu, Jie, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
This thesis describes routing in mobile ad hoc wireless networks. Ad hoc networks are lack of wired backbone to maintain routes as mobile hosts move and power is on or off. Therefore, the hosts in ad hoc networks must cooperate with each other to determine routes in a distributed manner. Routing based on a connected dominating set is a frequently used approach, where the searching space for a route is reduced to nodes in small connected dominating set subnetwork. We propose a simple and...
Show moreThis thesis describes routing in mobile ad hoc wireless networks. Ad hoc networks are lack of wired backbone to maintain routes as mobile hosts move and power is on or off. Therefore, the hosts in ad hoc networks must cooperate with each other to determine routes in a distributed manner. Routing based on a connected dominating set is a frequently used approach, where the searching space for a route is reduced to nodes in small connected dominating set subnetwork. We propose a simple and efficient distributed algorithm for calculating connected dominating set in a given un-directed ad hoc network, then evaluate the proposed algorithm through simulation. We also discuss connected dominating set update/recalculation algorithms when the topology of the ad hoc network changes. We also explore the possible extension of using hierarchical connected dominating set. The shortest path routing and the dynamic source routing, which are based on the connected dominating set subnetwork, are discussed.
Show less - Date Issued
- 1999
- PURL
- http://purl.flvc.org/fcla/dt/15695
- Subject Headings
- Mobile computing, Computer algorithms, Computer networks
- Format
- Document (PDF)
- Title
- Parallel algorithms for domain load balance.
- Creator
- Huang, Hao., Florida Atlantic University, Wu, Jie
- Abstract/Description
-
To improve the performance of parallel/distributed systems, we propose four parallel load balance algorithms. The new partition algorithm achieves load balance among processors via domain partition. If we assume the problem domain is evenly load distributed, this algorithm will divide the whole domain into a required number of subdomains with the same area. If a problem domain has a dynamic load distribution, although the new partition algorithm is still suitable for the initial mapping, we...
Show moreTo improve the performance of parallel/distributed systems, we propose four parallel load balance algorithms. The new partition algorithm achieves load balance among processors via domain partition. If we assume the problem domain is evenly load distributed, this algorithm will divide the whole domain into a required number of subdomains with the same area. If a problem domain has a dynamic load distribution, although the new partition algorithm is still suitable for the initial mapping, we propose three dynamic load balance algorithms. These dynamic algorithms achieve load balance among processors by transferring load among processors. We applied the new partition algorithm to a specific domain and compared the method to some existing partition algorithms. We also simulated three dynamic load balance algorithms. Results of comparisons and simulations show that all the four algorithms have satisfactory performance.
Show less - Date Issued
- 1997
- PURL
- http://purl.flvc.org/fcla/dt/15478
- Subject Headings
- Algorithms, Parallel processing (Electronic computers)
- Format
- Document (PDF)
- Title
- Complexity metrics in parallel computing.
- Creator
- Larrondo-Petrie, Maria M., Florida Atlantic University, Fernandez, Eduardo B., Coulter, Neal S., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
Accompanying the potential increase in power offered by parallel computers is an increase in the complexity of program design, implementation, testing and maintenance. It is important to understand the logical complexity of parallel programs in order to support the development of concurrent software. Measures are needed to quantify the components of parallel software complexity and to establish a basis for comparison and analysis of parallel algorithms at various stages of development and...
Show moreAccompanying the potential increase in power offered by parallel computers is an increase in the complexity of program design, implementation, testing and maintenance. It is important to understand the logical complexity of parallel programs in order to support the development of concurrent software. Measures are needed to quantify the components of parallel software complexity and to establish a basis for comparison and analysis of parallel algorithms at various stages of development and implementation. A set of primitive complexity measures is proposed that collectively describe the total complexity of parallel programs. The total complexity is separated into four dimensions or components: requirements, sequential, parallel and communication. Each proposed primitive measure is classified under one of these four areas. Two additional possible dimensions, fault-tolerance and real-time, are discussed. The total complexity measure is expressed as a vector of dimensions; each component is defined as a vector of primitive metrics. The method of quantifying each primitive metric is explained in detail. Those primitive metrics that contribute to the parallel and communications complexity are exercised against ten published summation algorithms and programs, illustrating that architecture has a significant effect on the complexity of parallel programs--even if the same programming language is used. The memory organization and the processor interconnection scheme had no effect on the parallel component, but did affect the communication component. Programming style and language did not have a noticeable effect on either component. The proposed metrics are quantifiable, consistent, and useful in comparing parallel algorithms. Unlike existing parallel metrics, they are general and applicable to different languages, architectures, algorithms, paradigms, programming styles and stages of software development.
Show less - Date Issued
- 1992
- PURL
- http://purl.flvc.org/fcla/dt/12296
- Subject Headings
- Parallel programming (Computer Science), Computer algorithms
- Format
- Document (PDF)
- Title
- Fault-tolerant routing in two-dimensional and three-dimensional meshes.
- Creator
- Chen, Xiao., Florida Atlantic University, Wu, Jie, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
Mesh-connected multicomputers are one of the simplest and least expensive structures to build a system using hundreds and even thousands of processors. The nodes communicate with each other by sending and receiving messages. As the system gets larger and larger, it not only requires the routing algorithms be efficient but also fault-tolerant. The fault model we use in 2-D meshes is a faulty block while in 3-D meshes, the fault model is a faculty cube. In order to route messages through...
Show moreMesh-connected multicomputers are one of the simplest and least expensive structures to build a system using hundreds and even thousands of processors. The nodes communicate with each other by sending and receiving messages. As the system gets larger and larger, it not only requires the routing algorithms be efficient but also fault-tolerant. The fault model we use in 2-D meshes is a faulty block while in 3-D meshes, the fault model is a faculty cube. In order to route messages through feasible minimum paths, the extended safety level is used to determine the existence of a minimal path and faulty block (cube) information is used to guide the routing. This dissertation presents an in-depth study of fault-tolerant minimal routing in 2-D tori, 3-D meshes, and tree-based fault-tolerant multicasting in 2-D and 3-D meshes using extended safety levels. Also path-based fault-tolerant deadlock-free multicasting in 2-D and 3-D meshes is studied. In fault-tolerant minimal routing in 2-D meshes, if no faulty block is encountered, any adaptive minimal routing can be used until the message encounters a faulty block. The next step is guided by the faulty block information until the message gets away from the faulty block. After that, any minimal adaptive routing can be used again. The minimal routing in 2-D tori is similar to that in 2-D meshes if at the beginning of the routing a conversion is made from a 2-D torus to a 2-D mesh. The fault-tolerant minimal routing in 3-D meshes can be done in a similar way. In the tree-based multicasting in 2-D and 3-D meshes, a time-step optimal and traffic-step suboptimal algorithm is proposed. Several heuristic strategies are presented to resolve a conflict, which are compared by simulations. A path-based fault-tolerant deadlock-free multicast algorithm in 2-D meshes with inter-block distance of at least three is presented to solve the deadlock problem in tree-based multicast algorithms. The approach is then extended to 3-D meshes and to inter-block distance of at least two in 2-D meshes. The path is Hamiltonian that is only updated locally in the neighborhood of a faulty block when a faulty block is encountered. Two virtual channels are used to prevent deadlock in 2-D and 3-D meshes with inter-block (inter-cube) distance of at least three and two more virtual channels are added if the inter-block distance is at least two.
Show less - Date Issued
- 1999
- PURL
- http://purl.flvc.org/fcla/dt/12597
- Subject Headings
- Fault-tolerant computing, Computer algorithms
- Format
- Document (PDF)
- Title
- Mobility pattern-based routing algorithm for mobile ad hoc wireless networks.
- Creator
- Vyas, Nirav., Florida Atlantic University, Mahgoub, Imad, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
This thesis describes routing in mobile ad hoc wireless networks. Ad hoc networks lack wired backbone to maintain routes as mobile hosts move and power is on or off. Therefore, the hosts in ad hoc networks must cooperate with each other to determine routes in a distributed manner. Routing based on a Location is a frequently used approach, where the searching space for a route is reduced to smaller zone by defining request zone and expected zone. We propose a mobility pattern based algorithm...
Show moreThis thesis describes routing in mobile ad hoc wireless networks. Ad hoc networks lack wired backbone to maintain routes as mobile hosts move and power is on or off. Therefore, the hosts in ad hoc networks must cooperate with each other to determine routes in a distributed manner. Routing based on a Location is a frequently used approach, where the searching space for a route is reduced to smaller zone by defining request zone and expected zone. We propose a mobility pattern based algorithm to reduce the overhead, then evaluate the proposed algorithm through simulation. We have implemented two mobility patterns into Location Aided Routing, namely, leading movement and random walk type mobility patterns. We have developed simulation model for each mobility pattern, using SES/Workbench. The performance is measured in terms of overhead of the network. We also discuss various routing algorithms such as dynamic source routing, zone routing protocol, associativity based routing protocol and ad hoc on demand distance vector routing.
Show less - Date Issued
- 2000
- PURL
- http://purl.flvc.org/fcla/dt/12662
- Subject Headings
- Mobile computing, Wireless communication systems, Computer algorithms
- Format
- Document (PDF)
- Title
- Achieving Higher Receiver Satisfaction using Multicast-Favored Bandwidth Allocation Protocols.
- Creator
- Yousefizadeh, Hooman, Zilouchian, Ali, Ilyas, Mohammad, Florida Atlantic University, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
In recent years, many protocols for efficient Multicasting have been proposed. However, many of the Internet Service Providers (ISPs) are reluctant to use multicastenabled routers in their networks. To provide such incentives, new protocols are needed to improve the quality of their services. The challenge is to find a compromise between allocating Bandwidth (BW) among different flows in a fair manner, and favoring multicast sessions over unicast sessions. In addition, the overall higher...
Show moreIn recent years, many protocols for efficient Multicasting have been proposed. However, many of the Internet Service Providers (ISPs) are reluctant to use multicastenabled routers in their networks. To provide such incentives, new protocols are needed to improve the quality of their services. The challenge is to find a compromise between allocating Bandwidth (BW) among different flows in a fair manner, and favoring multicast sessions over unicast sessions. In addition, the overall higher level of receiver satisfaction should be achieved. In this dissertation, we propose three new innovative protocols to favor multicast sessions over unicast sessions. Multicast Favored BW Allocation- Logarithmic (MFBA-Log) and Multicast Favored BW Allocation-Linear (MFBALin) protocols allocate BW proportional to the number of down stream receivers. The proposed Multicast Reserved BW Allocation (MRBA) protocol allocates part of the BW in the links only to multicast sessions. Simulation results show the increase in the overall level of Receiver Satisfaction in the network.
Show less - Date Issued
- 2006
- PURL
- http://purl.flvc.org/fau/fd/FA00012581
- Subject Headings
- Multicasting (Computer networks), Computer network protocols, Computer algorithms
- Format
- Document (PDF)
- Title
- Quantum Circuits for Symmetric Cryptanalysis.
- Creator
- Langenberg, Brandon Wade, Steinwandt, Rainer, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Mathematical Sciences
- Abstract/Description
-
Quantum computers and quantum computing is a reality of the near feature. Companies such as Google and IBM have already declared they have built a quantum computer and tend to increase their size and capacity moving forward. Quantum computers have the ability to be exponentially more powerful than classical computers today. With this power modeling behavior of atoms or chemical reactions in unusual conditions, improving weather forecasts and traffic conditions become possible. Also, their...
Show moreQuantum computers and quantum computing is a reality of the near feature. Companies such as Google and IBM have already declared they have built a quantum computer and tend to increase their size and capacity moving forward. Quantum computers have the ability to be exponentially more powerful than classical computers today. With this power modeling behavior of atoms or chemical reactions in unusual conditions, improving weather forecasts and traffic conditions become possible. Also, their ability to exponentially speed up some computations makes the security of todays data and items a major concern and interest. In the area of cryptography, some encryption schemes (such as RSA) are already deemed broken by the onset of quantum computing. Some encryption algorithms have already been created to be quantum secure and still more are being created each day. While these algorithms in use today are considered quantum-safe not much is known of what a quantum attack would look like on these algorithms. Specifically, this paper discusses how many quantum bits, quantum gates and even the depth of these gates that would be needed for such an attack. The research below was completed to shed light on these areas and offer some concrete numbers of such an attack.
Show less - Date Issued
- 2018
- PURL
- http://purl.flvc.org/fau/fd/FA00013010
- Subject Headings
- Quantum computing, Cryptography, Cryptanalysis, Data encryption (Computer science), Computer algorithms
- Format
- Document (PDF)
- Title
- Learning in connectionist networks using the Alopex algorithm.
- Creator
- Venugopal, Kootala Pattath., Florida Atlantic University, Pandya, Abhijit S., Sudhakar, Raghavan, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
The Alopex algorithm is presented as a universal learning algorithm for connectionist models. It is shown that the Alopex procedure could be used efficiently as a supervised learning algorithm for such models. The algorithm is demonstrated successfully on a variety of network architectures. Such architectures include multilayer perceptrons, time-delay models, asymmetric, fully recurrent networks and memory neuron networks. The learning performance as well as the generation capability of the...
Show moreThe Alopex algorithm is presented as a universal learning algorithm for connectionist models. It is shown that the Alopex procedure could be used efficiently as a supervised learning algorithm for such models. The algorithm is demonstrated successfully on a variety of network architectures. Such architectures include multilayer perceptrons, time-delay models, asymmetric, fully recurrent networks and memory neuron networks. The learning performance as well as the generation capability of the Alopex algorithm are compared with those of the backpropagation procedure, concerning a number of benchmark problems, and it is shown that the Alopex has specific advantages over the backpropagation. Two new architectures (gain layer schemes) are proposed for the on-line, direct adaptive control of dynamical systems using neural networks. The proposed schemes are shown to provide better dynamic response and tracking characteristics, than the other existing direct control schemes. A velocity reference scheme is introduced to improve the dynamic response of on-line learning controllers. The proposed learning algorithm and architectures are studied on three practical problems; (i) Classification of handwritten digits using Fourier Descriptors; (ii) Recognition of underwater targets from sonar returns, considering temporal dependencies of consecutive returns and (iii) On-line learning control of autonomous underwater vehicles, starting with random initial conditions. Detailed studies are conducted on the learning control applications. Effect of the network learning rate on the tracking performance and dynamic response of the system are investigated. Also, the ability of the neural network controllers to adapt to slow and sudden varying parameter disturbances and measurement noise is studied in detail.
Show less - Date Issued
- 1993
- PURL
- http://purl.flvc.org/fcla/dt/12325
- Subject Headings
- Computer algorithms, Computer networks, Neural networks (Computer science), Machine learning
- Format
- Document (PDF)
- Title
- Time-step optimal broadcasting in mesh networks with minimum total communication distance.
- Creator
- Cang, Songluan., Florida Atlantic University, Wu, Jie
- Abstract/Description
-
We propose a new minimum total communication distance (TCD) algorithm and an optimal TCD algorithm for broadcast in a 2-dimensional mesh (2-D mesh). The former generates a minimum TCD from a given source node, and the latter guarantees a minimum TCD among all the possible source nodes. These algorithms are based on a divide-and-conquer approach where a 2-D mesh is partitioned into four submeshes of equal size. The source node sends the broadcast message to a special node called an eye in each...
Show moreWe propose a new minimum total communication distance (TCD) algorithm and an optimal TCD algorithm for broadcast in a 2-dimensional mesh (2-D mesh). The former generates a minimum TCD from a given source node, and the latter guarantees a minimum TCD among all the possible source nodes. These algorithms are based on a divide-and-conquer approach where a 2-D mesh is partitioned into four submeshes of equal size. The source node sends the broadcast message to a special node called an eye in each submesh. The above procedure is then recursively applied in each submesh. These algorithms are extended to a 3-dimensional mesh (3-D mesh), and are generalized to a d-dimensional mesh or torus. In addition, the proposed approach can potentially be used to solve optimization problems in other collective communication operations.
Show less - Date Issued
- 1999
- PURL
- http://purl.flvc.org/fcla/dt/15647
- Subject Headings
- Computer algorithms, Parallel processing (Electronic computers), Computer architecture
- Format
- Document (PDF)
- Title
- CONTRIBUTIONS TO QUANTUM-SAFE CRYPTOGRAPHY: HYBRID ENCRYPTION AND REDUCING THE T GATE COST OF AES.
- Creator
- Pham, Hai, Steinwandt, Rainer, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Mathematical Sciences
- Abstract/Description
-
Quantum cryptography offers a wonderful source for current and future research. The idea started in the early 1970s, and it continues to inspire work and development toward a popular goal, large-scale communication networks with strong security guarantees, based on quantum-mechanical properties. Quantum cryptography builds on the idea of exploiting physical properties to establish secure cryptographic operations. A particular quantum-based protocol has gathered interest in recent years for...
Show moreQuantum cryptography offers a wonderful source for current and future research. The idea started in the early 1970s, and it continues to inspire work and development toward a popular goal, large-scale communication networks with strong security guarantees, based on quantum-mechanical properties. Quantum cryptography builds on the idea of exploiting physical properties to establish secure cryptographic operations. A particular quantum-based protocol has gathered interest in recent years for its use of mesoscopic coherent states. The AlphaEta protocol has been designed to exploit properties of coherent states of light to transmit data securely over an optical channel. AlphaEta aims to draw security from the uncertainty of any measurement of the transmitted coherent states due to intrinsic quantum noise. We propose a framework to combine this protocol with classical preprocessing, taking into account error-correction for the optical channel and establishing a strong provable security guarantee. Integrating a state-of-the-art solution for fast authenticated encryption is straightforward, but in this case the security analysis requires heuristic reasoning.
Show less - Date Issued
- 2019
- PURL
- http://purl.flvc.org/fau/fd/FA00013339
- Subject Headings
- Cryptography, Quantum computing, Algorithms, Mesoscopic coherent states
- Format
- Document (PDF)
- Title
- ALGORITHMS IN LATTICE-BASED CRYPTANALYSIS.
- Creator
- Miller, Shaun, Bai, Shi, Florida Atlantic University, Department of Mathematical Sciences, Charles E. Schmidt College of Science
- Abstract/Description
-
An adversary armed with a quantum computer has algorithms[66, 33, 34] at their disposal, which are capable of breaking our current methods of encryption. Even with the birth of post-quantum cryptography[52, 62, 61], some of best cryptanalytic algorithms are still quantum [45, 8]. This thesis contains several experiments on the efficacy of lattice reduction algorithms, BKZ and LLL. In particular, the difficulty of solving Learning With Errors is assessed by reducing the problem to an instance...
Show moreAn adversary armed with a quantum computer has algorithms[66, 33, 34] at their disposal, which are capable of breaking our current methods of encryption. Even with the birth of post-quantum cryptography[52, 62, 61], some of best cryptanalytic algorithms are still quantum [45, 8]. This thesis contains several experiments on the efficacy of lattice reduction algorithms, BKZ and LLL. In particular, the difficulty of solving Learning With Errors is assessed by reducing the problem to an instance of the Unique Shortest Vector Problem. The results are used to predict the behavior these algorithms may have on actual cryptographic schemes with security based on hard lattice problems. Lattice reduction algorithms require several floating-point operations including multiplication. In this thesis, I consider the resource requirements of a quantum circuit designed to simulate floating-point multiplication with high precision.
Show less - Date Issued
- 2020
- PURL
- http://purl.flvc.org/fau/fd/FA00013543
- Subject Headings
- Cryptanalysis, Cryptography, Algorithms, Lattices, Quantum computing
- Format
- Document (PDF)
- Title
- Cryptanalysis of small private key RSA.
- Creator
- Guild, Jeffrey Kirk, Florida Atlantic University, Klingler, Lee
- Abstract/Description
-
RSA cryptosystems with decryption exponent d less than N 0.292, for a given RSA modulus N, show themselves to be vulnerable to an attack which utilizes modular polynomials and the LLL Basis Reduction Algorithm. This result, presented by Dan Boneh and Glenn Durfee in 1999, is an improvement on the bound of N0.25 established by Wiener in 1990. This thesis examines in detail the LLL Basis Reduction Algorithm and the attack on RSA as presented by Boneh and Durfee.
- Date Issued
- 1999
- PURL
- http://purl.flvc.org/fcla/dt/15730
- Subject Headings
- Cryptography, Algorithms, Data encryption (Computer science)
- Format
- Document (PDF)
- Title
- Evolution and application of a parallel algorithm for explicit transient finite element analysis on SIMD/MIMD computers.
- Creator
- Das, Partha S., Florida Atlantic University, Case, Robert O., Tsai, Chi-Tay, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
- Abstract/Description
-
The development of a parallel data structure and an associated elemental decomposition algorithm for explicit finite element analysis for massively parallel SIMD computer, the DECmpp 12000 (MasPar MP-1) machine, is presented, and then extended to implementation on the MIMD computer, Cray-T3D. The new parallel data structure and elemental decomposition algorithm are discussed in detail and is used to parallelize a sequential Fortran code that deals with the application of isoparametric...
Show moreThe development of a parallel data structure and an associated elemental decomposition algorithm for explicit finite element analysis for massively parallel SIMD computer, the DECmpp 12000 (MasPar MP-1) machine, is presented, and then extended to implementation on the MIMD computer, Cray-T3D. The new parallel data structure and elemental decomposition algorithm are discussed in detail and is used to parallelize a sequential Fortran code that deals with the application of isoparametric elements for the nonlinear dynamic analysis of shells of revolution. The parallel algorithm required the development of a new procedure, called an 'exchange', which consists of an exchange of nodal forces at each time step to replace the standard gather-assembly operations in sequential code. In addition, the data was reconfigured so that all nodal variables associated with an element are stored in a processor along with other element data. The architectural and Fortran programming language features of the MasPar MP-1 and Cray-T3D computers which are pertinent to finite element computations are also summarized, and sample code segments are provided to illustrate programming in a data parallel environment. The governing equations, the finite element discretization and a comparison between their implementation on Von Neumann and SIMD-MIMD parallel computers are discussed to demonstrate their applicability and the important differences in the new algorithm. Various large scale transient problems are solved using the parallel data structure and elemental decomposition algorithm and measured performances are presented and analyzed in detail. Results show that Cray-T3D is a very promising parallel computer for finite element computation. The 32 processors of this machine shows an overall speedup of 27-28, i.e. an efficiency of 85% or more and 128 processors shows a speedup of 70-77, i.e. an efficiency of 55% or more. The Cray-T3D results demonstrated that this machine is capable of outperforming the Cray-YMP by a factor of about 10 for finite element problems with 4K elements, therefore, the method of developing the parallel data structure and its associated elemental decomposition algorithm is recommended for implementation on other finite element code in this machine. However, the results from MasPar MP-1 show that this new algorithm for explicit finite element computations do not produce very efficient parallel code on this computer and therefore, the new data structure is not recommended for further use on this MasPar machine.
Show less - Date Issued
- 1997
- PURL
- http://purl.flvc.org/fcla/dt/12500
- Subject Headings
- Finite element method, Algorithms, Parallel computers
- Format
- Document (PDF)
- Title
- Examples of deterministic and Monte Carlo algorithms for cryptographic applications.
- Creator
- McPherson, Joe Cullen, Florida Atlantic University, Hoffman, Frederick
- Abstract/Description
-
In this thesis two different types of computer algorithms, Deterministic and Monte Carlo, are illustrated. Implementations of the Berlekamp-Massey algorithm and the Parallelized Pollard Rho Search are described here. The questions of what these two algorithms provide to the field of cryptography and why they have proven themselves important to cryptography are briefly discussed. It is also shown that with a little extra knowledge, the Parallelized Pollard Rho Search may be easily modified to...
Show moreIn this thesis two different types of computer algorithms, Deterministic and Monte Carlo, are illustrated. Implementations of the Berlekamp-Massey algorithm and the Parallelized Pollard Rho Search are described here. The questions of what these two algorithms provide to the field of cryptography and why they have proven themselves important to cryptography are briefly discussed. It is also shown that with a little extra knowledge, the Parallelized Pollard Rho Search may be easily modified to improve its performance.
Show less - Date Issued
- 2000
- PURL
- http://purl.flvc.org/fcla/dt/12687
- Subject Headings
- Monte Carlo method, Computer algorithms, Cryptography
- Format
- Document (PDF)
- Title
- Information-theoretics based genetic algorithm: Application to Hopfield's associative memory model of neural networks.
- Creator
- Arredondo, Tomas Vidal., Florida Atlantic University, Neelakanta, Perambur S.
- Abstract/Description
-
This thesis refers to a research addressing the use of information-theoretic techniques in optimizing an artificial neural network (ANN) via a genetic selection algorithm. Pertinent studies address emulating relevant experiments on a test ANN (based on Hopfield's associative memory model) wherein the said optimization is tried with different sets of control parameters. These parameters include a new entity based on the concept of entropy as conceived in the field of information theory. That...
Show moreThis thesis refers to a research addressing the use of information-theoretic techniques in optimizing an artificial neural network (ANN) via a genetic selection algorithm. Pertinent studies address emulating relevant experiments on a test ANN (based on Hopfield's associative memory model) wherein the said optimization is tried with different sets of control parameters. These parameters include a new entity based on the concept of entropy as conceived in the field of information theory. That is, the mutual entropy (Shannon entropy) or information-distance (Kullback-Leibler-Jensen distance) measure between a pair of candidates is considered in the reproduction process of the genetic algorithm (GA) and adopted as a selection-constraint parameter. The research envisaged further includes a comparative analysis of the test results which indicate the importance of proper parameter selection to realize an optimal network performance. It also demonstrates the ability of the concepts proposed here in developing a new neural network approach for pattern recognition problems.
Show less - Date Issued
- 1997
- PURL
- http://purl.flvc.org/fcla/dt/15397
- Subject Headings
- Neuro network (Computer science), Genetic algorithms
- Format
- Document (PDF)
- Title
- Comparison of different realizations and adaptive algorithms for channel equalization.
- Creator
- Kamath, Anuradha K., Florida Atlantic University, Sudhakar, Raghavan, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
This thesis presents simulation results comparing the performance of different realizations and adaptive algorithms for channel equalization. An attempt is made to study and compare the performance of some filter structures used as an equalizer in fast data transmission over the baseband channel. To this end, simulation experiments are performed using minimum and non minimum phase channel models with adaptation algorithms such as the least mean square (LMS) and recursive least square (RLS)...
Show moreThis thesis presents simulation results comparing the performance of different realizations and adaptive algorithms for channel equalization. An attempt is made to study and compare the performance of some filter structures used as an equalizer in fast data transmission over the baseband channel. To this end, simulation experiments are performed using minimum and non minimum phase channel models with adaptation algorithms such as the least mean square (LMS) and recursive least square (RLS) algorithms, filter structures such as the lattice and transversal filters and the input signals such as the binary phase shift keyed (BPSK) and quadrature phase shift keyed (QPSK) signals. Based on the simulation studies, conclusions are drawn regarding the performance of various adaptation algorithms.
Show less - Date Issued
- 1993
- PURL
- http://purl.flvc.org/fcla/dt/14974
- Subject Headings
- Computer algorithms, Data transmission systems, Equalizers (Electronics)
- Format
- Document (PDF)
- Title
- MACHINE LEARNING ALGORITHMS FOR THE DETECTION AND ANALYSIS OF WEB ATTACKS.
- Creator
- Zuech, Richard, Khoshgoftaar, Taghi M., Florida Atlantic University, Department of Computer and Electrical Engineering and Computer Science, College of Engineering and Computer Science
- Abstract/Description
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The Internet has provided humanity with many great benefits, but it has also introduced new risks and dangers. E-commerce and other web portals have become large industries with big data. Criminals and other bad actors constantly seek to exploit these web properties through web attacks. Being able to properly detect these web attacks is a crucial component in the overall cybersecurity landscape. Machine learning is one tool that can assist in detecting web attacks. However, properly using...
Show moreThe Internet has provided humanity with many great benefits, but it has also introduced new risks and dangers. E-commerce and other web portals have become large industries with big data. Criminals and other bad actors constantly seek to exploit these web properties through web attacks. Being able to properly detect these web attacks is a crucial component in the overall cybersecurity landscape. Machine learning is one tool that can assist in detecting web attacks. However, properly using machine learning to detect web attacks does not come without its challenges. Classification algorithms can have difficulty with severe levels of class imbalance. Class imbalance occurs when one class label disproportionately outnumbers another class label. For example, in cybersecurity, it is common for the negative (normal) label to severely outnumber the positive (attack) label. Another difficulty encountered in machine learning is models can be complex, thus making it difficult for even subject matter experts to truly understand a model’s detection process. Moreover, it is important for practitioners to determine which input features to include or exclude in their models for optimal detection performance. This dissertation studies machine learning algorithms in detecting web attacks with big data. Severe class imbalance is a common problem in cybersecurity, and mainstream machine learning research does not sufficiently consider this with web attacks. Our research first investigates the problems associated with severe class imbalance and rarity. Rarity is an extreme form of class imbalance where the positive class suffers extremely low positive class count, thus making it difficult for the classifiers to discriminate. In reducing imbalance, we demonstrate random undersampling can effectively mitigate the class imbalance and rarity problems associated with web attacks. Furthermore, our research introduces a novel feature popularity technique which produces easier to understand models by only including the fewer, most popular features. Feature popularity granted us new insights into the web attack detection process, even though we had already intensely studied it. Even so, we proceed cautiously in selecting the best input features, as we determined that the “most important” Destination Port feature might be contaminated by lopsided traffic distributions.
Show less - Date Issued
- 2021
- PURL
- http://purl.flvc.org/fau/fd/FA00013823
- Subject Headings
- Machine learning, Computer security, Algorithms, Cybersecurity
- Format
- Document (PDF)
- Title
- Enhanced 1-D chaotic key-based algorithm for image encryption.
- Creator
- Furht, Borko, Socek, Daniel, Magliveras, Spyros S.
- Abstract/Description
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A recently proposed Chaotic-Key Based Algorithm (CKBA) has been shown to be unavoidably susceptible to chosen/known-plaintext attacks and ciphertext-only attacks. In this paper we enhance the CKBA algorithm three-fold: 1) we change the 1-D chaotic Logistic map to a piecewise linear chaotic map (PWLCM) to improve the balance property, 2) we increase the key size to 128 bits, and 3) we add two more cryptographic primitives and extend the scheme to operate on multiple rounds so that the chosen...
Show moreA recently proposed Chaotic-Key Based Algorithm (CKBA) has been shown to be unavoidably susceptible to chosen/known-plaintext attacks and ciphertext-only attacks. In this paper we enhance the CKBA algorithm three-fold: 1) we change the 1-D chaotic Logistic map to a piecewise linear chaotic map (PWLCM) to improve the balance property, 2) we increase the key size to 128 bits, and 3) we add two more cryptographic primitives and extend the scheme to operate on multiple rounds so that the chosen/knownplaintext attacks are no longer possible. The new cipher has much stronger security and its performance characteristics remain very good.
Show less - Date Issued
- 2004-11-22
- PURL
- http://purl.flvc.org/fcla/dt/358402
- Subject Headings
- Data encryption (Computer science), Computer algorithm, Mulitmedia systems --Security measures.
- Format
- Document (PDF)
- Title
- Design and modeling of hybrid software fault-tolerant systems.
- Creator
- Zhang, Man-xia Maria., Florida Atlantic University, Wu, Jie, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
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Fault tolerant programming methods improve software reliability using the principles of design diversity and redundancy. Design diversity and redundancy, on the other hand, escalate the cost of the software design and development. In this thesis, we study the reliability of hybrid fault tolerant systems. Probability models based on fault trees are developed for the recovery block (RB), N-version programming (NVP) and hybrid schemes which are the combinations of RB and NVP. Two heuristic...
Show moreFault tolerant programming methods improve software reliability using the principles of design diversity and redundancy. Design diversity and redundancy, on the other hand, escalate the cost of the software design and development. In this thesis, we study the reliability of hybrid fault tolerant systems. Probability models based on fault trees are developed for the recovery block (RB), N-version programming (NVP) and hybrid schemes which are the combinations of RB and NVP. Two heuristic methods are developed to construct hybrid fault tolerant systems with total cost constraints. The algorithms provide a systematic approach to the design of hybrid fault tolerant systems.
Show less - Date Issued
- 1992
- PURL
- http://purl.flvc.org/fcla/dt/14783
- Subject Headings
- Computer software--Reliability, Fault-tolerant computing, Algorithms
- Format
- Document (PDF)
