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- Title
- A VLSI implementable thinning algorithm.
- Creator
- Zhang, Wei, Florida Atlantic University, Shankar, Ravi, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
Thinning is a very important step in a Character Recognition System. This thesis evolves a thinning algorithm that can be hardware implemented to improve the speed of the process. The software thinning algorithm features a simple set of rules that can be applied on both hexagonal and orthogonal character images. The hardware architecture features the SIMD structure, simple processing elements and near neighbor communications. The algorithm was simulated against the U.S. Postal Service...
Show moreThinning is a very important step in a Character Recognition System. This thesis evolves a thinning algorithm that can be hardware implemented to improve the speed of the process. The software thinning algorithm features a simple set of rules that can be applied on both hexagonal and orthogonal character images. The hardware architecture features the SIMD structure, simple processing elements and near neighbor communications. The algorithm was simulated against the U.S. Postal Service Character Database. The architecture, evolved with consideration of both the software constraints and the physical layout limitations, was simulated using VHDL hardware description language. Subsequent to VLSI design and simulations the chip was fabricated. The project provides for a feasibility study in utilizing the parallel processor architecture for the implementation of a parallel image thinning algorithm. It is hoped that such a hardware implementation will speed up the processing and lead eventually to a real time system.
Show less - Date Issued
- 1992
- PURL
- http://purl.flvc.org/fcla/dt/14837
- Subject Headings
- Optical character recognition devices--Computer simulation, Algorithms, Integrated circuits--Very large scale integration
- Format
- Document (PDF)
- Title
- THE CHANGE POINT PROBLEM FOR TWO CLASSES OF STOCHASTIC PROCESSES.
- Creator
- Ball, Cory, Long, Hongwei, Florida Atlantic University, Department of Mathematical Sciences, Charles E. Schmidt College of Science
- Abstract/Description
-
The change point problem is a problem where a process changes regimes because a parameter changes at a point in time called the change point. The objective of this problem is to estimate the change point and each of the parameters of the stochastic process. In this thesis, we examine the change point problem for two classes of stochastic processes. First, we consider the volatility change point problem for stochastic diffusion processes driven by Brownian motions. Then, we consider the drift...
Show moreThe change point problem is a problem where a process changes regimes because a parameter changes at a point in time called the change point. The objective of this problem is to estimate the change point and each of the parameters of the stochastic process. In this thesis, we examine the change point problem for two classes of stochastic processes. First, we consider the volatility change point problem for stochastic diffusion processes driven by Brownian motions. Then, we consider the drift change point problem for Ornstein-Uhlenbeck processes driven by _-stable Levy motions. In each problem, we establish the consistency of the estimators, determine asymptotic behavior for the changing parameters, and finally, we perform simulation studies to computationally assess the convergence of parameters.
Show less - Date Issued
- 2020
- PURL
- http://purl.flvc.org/fau/fd/FA00013462
- Subject Headings
- Stochastic processes, Change-point problems, Brownian motion processes, Ornstein-Uhlenbeck process, Computer simulation
- Format
- Document (PDF)
- Title
- FINANCIAL TIME-SERIES ANALYSIS WITH DEEP NEURAL NETWORKS.
- Creator
- Rimal, Binod, Hahn, William Edward, Florida Atlantic University, Department of Mathematical Sciences, Charles E. Schmidt College of Science
- Abstract/Description
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Financial time-series data are noisy, volatile, and nonlinear. The classic statistical linear models may not capture those underlying structures of the data. The rapid advancement in artificial intelligence and machine learning techniques, availability of large-scale data, and increased computational capabilities of a machine opens the door to developing sophisticated deep learning models to capture the nonlinearity and hidden information in the data. Creating a robust model by unlocking the...
Show moreFinancial time-series data are noisy, volatile, and nonlinear. The classic statistical linear models may not capture those underlying structures of the data. The rapid advancement in artificial intelligence and machine learning techniques, availability of large-scale data, and increased computational capabilities of a machine opens the door to developing sophisticated deep learning models to capture the nonlinearity and hidden information in the data. Creating a robust model by unlocking the power of a deep neural network and using real-time data is essential in this tech era. This study constructs a new computational framework to uncover the information in the financial time-series data and better inform the related parties. It carries out the comparative analysis of the performance of the deep learning models on stock price prediction with a well-balanced set of factors from fundamental data, macroeconomic data, and technical indicators responsible for stock price movement. We further build a novel computational framework through a merger of recurrent neural networks and random compression for the time-series analysis. The performance of the model is tested on a benchmark anomaly time-series dataset. This new computational framework in a compressed paradigm leads to improved computational efficiency and data privacy. Finally, this study develops a custom trading simulator and an agent-based hybrid model by combining gradient and gradient-free optimization methods. In particular, we explore the use of simulated annealing with stochastic gradient descent. The model trains a population of agents to predict appropriate trading behaviors such as buy, hold, or sell by optimizing the portfolio returns. Experimental results on S&P 500 index show that the proposed model outperforms the baseline models.
Show less - Date Issued
- 2022
- PURL
- http://purl.flvc.org/fau/fd/FA00014009
- Subject Headings
- Neural networks (Computer science), Deep learning (Machine learning), Time-series analysis, Stocks, Simulated annealing (Mathematics)
- Format
- Document (PDF)
- Title
- A Hybrid System for Simulation of Athletic Activities Related to Lower Extremity Biomechanics.
- Creator
- Trepeck, Cameron, Hashemi, Javad, Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
- Abstract/Description
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In this dissertation, the design and development of a hybrid robotic system that simulates dynamic biomechanical tasks of the lower extremity with emphasis on knee and hip joints are presented. The hybrid system utilizes a mechanical hip and a cadaveric knee/ankle component and can accelerate the whole complex towards the ground. This system is used to simulate complex athletic movements such as landing from a jump at various anatomical orientations of the lower extremity with muscle action....
Show moreIn this dissertation, the design and development of a hybrid robotic system that simulates dynamic biomechanical tasks of the lower extremity with emphasis on knee and hip joints are presented. The hybrid system utilizes a mechanical hip and a cadaveric knee/ankle component and can accelerate the whole complex towards the ground. This system is used to simulate complex athletic movements such as landing from a jump at various anatomical orientations of the lower extremity with muscle action. The dynamic response of the lower extremity is monitored and analyzed during impulsive contact between the ground and the cadaveric leg. The cadaveric knee is instrumented to measure strain of the Anterior Cruciate Ligament (ACL) during simulated high impact sports activities. The mechanical hip allows various kinematics of the hip including flexion as well as abduction. In addition to the flexion and abduction of the mechanical hip, the controlled flexion and extension of the cadaveric knee allows for simulation of complex tasks such as landing from a jump. A large number of tests were performed at various anatomical positions utilizing this device to simulate landing from a jump. ACL strain was measured during these tasks using a Differential Variance Resistance Transducer (DVRT). Ground Reaction Force and muscle forces were measured and monitored using AmCell load cells recorded using the LabView software. one-inch and 6-inch jump landing heights were used for all the simulations. The tests were performed at differing angles of hip flexion (0°, 30°, 45°, 60°) and at two different ankle positions. Plantar flexion and flat-footed landing conditions were simulated and compared in all degrees of hip flexion. These tests were repeated with and without hip abduction in order to study the effects of these landing positions on ACL strain. Hip flexion was found to effect ACL strain: as angle of hip flexion increases, ACL strain decreases. This occurred in both abducted and non-abducted hip positions. Ankle landing position had an effect only in small drop heights, while hip abduction had an effect in large drops. Future tests must be completed to further study these effects. These studies showed that the robotic system can simulate dynamic tasks, apply muscle forces, and move the cadaveric tissue in three dimensional biomechanical positions.
Show less - Date Issued
- 2017
- PURL
- http://purl.flvc.org/fau/fd/FA00004898, http://purl.flvc.org/fau/fd/FA00004898
- Subject Headings
- Musculoskeletal system--Wounds and injuries., Musculoskeletal system--Mechanical properties., Biomechanics--Computer simulation., Human mechanics., Artificial joints.
- Format
- Document (PDF)
- Title
- Exploring appropriate offset values for pencil beam and Monte Carlo dose optimization in lung stereotactic body radiotherapy encompassing the effects of respiration and tumor location.
- Creator
- Evans, Grant, Shang, Charles, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Physics
- Abstract/Description
-
Evaluation of dose optimization using the Pencil Beam (PB) and Monte Carlo (MC) algorithms may allow physicists to apply dosimetric offsets to account for inaccuracies of the PB algorithm for lung cancer treatment with Stereotactic Body Radiotherapy (SBRT). 20 cases of Non-Small Cell Lung Cancer (NSCLC) were selected. Treatment plans were created with Brainlab iPlanDose® 4.1.2. The D97 of the Planning Target Volume (PTV) was normalized to 50 Gy on the Average Intensity Projection (AIP) using...
Show moreEvaluation of dose optimization using the Pencil Beam (PB) and Monte Carlo (MC) algorithms may allow physicists to apply dosimetric offsets to account for inaccuracies of the PB algorithm for lung cancer treatment with Stereotactic Body Radiotherapy (SBRT). 20 cases of Non-Small Cell Lung Cancer (NSCLC) were selected. Treatment plans were created with Brainlab iPlanDose® 4.1.2. The D97 of the Planning Target Volume (PTV) was normalized to 50 Gy on the Average Intensity Projection (AIP) using the fast PB and compared with MC. This exact plan with the same beam Monitor Units (MUs) was recalculated over each respiratory phase. The results show that the PB algorithm has a 2.3-2.4% less overestimation at the maximum exhalation phase than the maximum inhalation phase when compared to MC. Significantly smaller dose difference between PB and MC is also shown in plans for peripheral lesions (7.7 ± 0.7%) versus central lesions (12.7±0.8%)(p< 0.01).
Show less - Date Issued
- 2014
- PURL
- http://purl.flvc.org/fau/fd/FA00004105, http://purl.flvc.org/fau/fd/FA00004105
- Subject Headings
- Drug development -- Computer simulation, Image guided radiation therapy, Lung cancer -- Treatment, Monte Carlo method, Proton beams, Transport theory
- Format
- Document (PDF)
- Title
- MODELING GROUND ELEVATION OF LOUISIANA COASTAL WETLANDS AND ANALYZING RELATIVE SEA LEVEL RISE INUNDATION USING RSET-MH AND LIDAR MEASUREMENTS.
- Creator
- Liu, Jing, Zhang, Caiyun, Florida Atlantic University, Department of Geosciences, Charles E. Schmidt College of Science
- Abstract/Description
-
The Louisiana coastal ecosystem is experiencing increasing threats from human flood control construction, sea-level rise (SLR), and subsidence. Louisiana lost about 4,833 km2 of coastal wetlands from 1932 to 2016, and concern exists whether remaining wetlands will persist while facing the highest rate of relative sea-level rise (RSLR) in the world. Restoration aimed at rehabilitating the ongoing and future disturbances is currently underway through the implementation of the Coastal Wetlands...
Show moreThe Louisiana coastal ecosystem is experiencing increasing threats from human flood control construction, sea-level rise (SLR), and subsidence. Louisiana lost about 4,833 km2 of coastal wetlands from 1932 to 2016, and concern exists whether remaining wetlands will persist while facing the highest rate of relative sea-level rise (RSLR) in the world. Restoration aimed at rehabilitating the ongoing and future disturbances is currently underway through the implementation of the Coastal Wetlands Planning Protection and Restoration Act of 1990 (CWPPRA). To effectively monitor the progress of projects in CWPPRA, the Coastwide Reference Monitoring System (CRMS) was established in 2006. To date, more than a decade of valuable coastal, environmental, and ground elevation data have been collected and archived. This dataset offers a unique opportunity to evaluate the wetland ground elevation dynamics by linking the Rod Surface Elevation Table (RSET) measurements with environmental variables like water salinity and biophysical variables like canopy coverage. This dissertation research examined the effects of the environmental and biophysical variables on wetland terrain elevation by developing innovative machine learning based models to quantify the contribution of each factor using the CRMS collected dataset. Three modern machine learning algorithms, including Random Forest (RF), Support Vector Machine (SVM), and Artificial Neural Network (ANN), were assessed and cross-compared with the commonly used Multiple Linear Regression (MLR). The results showed that RF had the best performance in modeling ground elevation with Root Mean Square Error (RMSE) of 10.8 cm and coefficient of coefficient (r) = 0.74. The top four factors contributing to ground elevation are the distance from monitoring station to closest water source, water salinity, water elevation, and dominant vegetation height.
Show less - Date Issued
- 2020
- PURL
- http://purl.flvc.org/fau/fd/FA00013568
- Subject Headings
- Coastal zone management--Louisiana, Sea level rise, Inundations, Wetland restoration--Louisiana, Machine learning, Computer simulation, Algorithms.
- Format
- Document (PDF)
- Title
- A study on the electromagnetic performance of body-worn radio units in the presence of scatterers in the proximity.
- Creator
- Peterson, Vance Howard, Florida Atlantic University, Ungvichian, Vichate, Neelakanta, Perambur S., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
The research addressed refers to a study on the electromagnetic performance aspects of body-worn radio units operating in the presence of scatterers in close proximity, using analytical, numerical, and experimental methods. The application potentials of such methods include evaluating the integrity of radio units such as cell phones. Consistent with the scope of the study above, considered in this research are specific details on analytical and numerical modeling of the effects of a nearby...
Show moreThe research addressed refers to a study on the electromagnetic performance aspects of body-worn radio units operating in the presence of scatterers in close proximity, using analytical, numerical, and experimental methods. The application potentials of such methods include evaluating the integrity of radio units such as cell phones. Consistent with the scope of the study above, considered in this research are specific details on analytical and numerical modeling of the effects of a nearby conducting cylindrical object on the electromagnetic field near a human-model phantom. Calculations are performed using the Finite Difference Time Domain (FDTD) method. Considered are various separations of the body wearing the test radio unit from the proximal object and polarization of the incident wave. An anechoic chamber and the test setup used for the measurement of EM field amplitudes near a saline-water phantom are described. Within the anechoic chamber, a small shielded loop is used as a field measurement probe and is positioned near the test phantom. The field probe orientation was in the vertical plane for characterizing the prevailing electromagnetic field intensity. This study indicates that variations in the field amplitude near the phantom occur, which are responsive to phantom rotation and measurement distance from the phantom. The electromagnetic field amplitude decreases rapidly with increasing distance between the probe and the surface of the phantom. The analysis is also extended to examine the electromagnetic field distribution in the gap between a human body phantom model and a nearby conducting cylinder. An appropriate three-dimensional FDTD method is presented and applied to a near-field problem of analyzing the influence of proximal conductive objects on fields near a phantom wearing an RF unit.
Show less - Date Issued
- 2004
- PURL
- http://purl.flvc.org/fau/fd/FADT12085
- Subject Headings
- Scattering (Mathematics), Sound-waves (Scattering), Electromagnetic waves--Scattering, Electromagnetism--Computer simulation, Finite differences, Time-domain analysis
- Format
- Document (PDF)
- Title
- Groundwater solute transport models for simulating the effects of a wellfield protection zone on contaminant transport.
- Creator
- Rueckert, William A., Florida Atlantic University, Restrepo, Jorge I.
- Abstract/Description
-
The objective is to develop a groundwater flow model of the Surficial Aquifer System in the area of Plantation, Broward County, Florida, using the U.S. Geological Survey MODFLOW code and to make a comparison between the use of two supplementary contaminant transport models: MODPATH code and the MT3D code. The advantages and limitations of the two solute transport models are described and an evaluation is made of their accuracy with respect to delineation of traveltime related to capture zones...
Show moreThe objective is to develop a groundwater flow model of the Surficial Aquifer System in the area of Plantation, Broward County, Florida, using the U.S. Geological Survey MODFLOW code and to make a comparison between the use of two supplementary contaminant transport models: MODPATH code and the MT3D code. The advantages and limitations of the two solute transport models are described and an evaluation is made of their accuracy with respect to delineation of traveltime related to capture zones of wells. Final results of the computer simulations indicate that this study area is sensitive to river bed hydraulic conductivity and the stress of the continuous pumping at a nearby wellfield. Therefore, a critical factor in selecting an appropriate flow model for delineating the traveltime-related capture zone of a well is a model which simplifies the flow system while still preserving hydrogeologic characteristics of the flow system.
Show less - Date Issued
- 1994
- PURL
- http://purl.flvc.org/fcla/dt/15073
- Subject Headings
- Pollutants, Groundwater flow--Computer simulation, Groundwater--Pollution, Aquifers--Florida--Broward County, Groundwater flow--Florida--Broward County
- Format
- Document (PDF)
- Title
- Innovative web applications for analyzing traffic operations.
- Creator
- Petrovska, Natasha, Furht, Borko, Stevanovic, Aleksandar, Florida Atlantic University, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
The road traffic along with other key infrastructure sectors such as telecommunication, power, etc. has an important role in economic and technological growth of one country. Traffic engineers and analysts are responsible for solving a diversity of traffic problems, such as traffic data acquisition and evaluation. In response to the need to improve traffic operation, researchers implement advanced technologies and integration of systems and data, and develop state-of-the-art applications....
Show moreThe road traffic along with other key infrastructure sectors such as telecommunication, power, etc. has an important role in economic and technological growth of one country. Traffic engineers and analysts are responsible for solving a diversity of traffic problems, such as traffic data acquisition and evaluation. In response to the need to improve traffic operation, researchers implement advanced technologies and integration of systems and data, and develop state-of-the-art applications. This thesis introduces three novel web applications with an aim to offer traffic operators, managers, and analysts’ possibility to monitor the congestion, and analyze incidents and signal performance measures. They offer more detailed analysis providing users with insights from different levels and perspectives. The benefit of providing these visualization tools is more efficient estimation of the performance of local networks, thus facilitating the decision making process in case of emergency events.
Show less - Date Issued
- 2015
- PURL
- http://purl.flvc.org/fau/fd/FA00004459, http://purl.flvc.org/fau/fd/FA00004459
- Subject Headings
- Application program interfaces (Computer software), Internet -- Mathematical models, Traffic congestion -- Management, Traffic estimation -- Computer simulation, Transportation demand -- Forecasting
- Format
- Document (PDF)
- Title
- A dosimetric study of a heterogeneous phantom for lung stereotactic body radiation therapy comparing Monte Carlo and pencil beam calculations to dose distributions measured with a 2-d diode array.
- Creator
- Curley, Casey Michael, Ouhib, Zoubir, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Physics
- Abstract/Description
-
Monte Carlo (MC) and Pencil Beam (PB) calculations are compared to their measured planar dose distributions using a 2-D diode array for lung Stereotactic Body Radiation Therapy (SBRT). The planar dose distributions were studied for two different phantom types: an in-house heterogeneous phantom and a homogeneous phantom. The motivation is to mimic the human anatomy during a lung SBRT treatment and incorporate heterogeneities into the pre-treatment Quality Assurance process, where measured and...
Show moreMonte Carlo (MC) and Pencil Beam (PB) calculations are compared to their measured planar dose distributions using a 2-D diode array for lung Stereotactic Body Radiation Therapy (SBRT). The planar dose distributions were studied for two different phantom types: an in-house heterogeneous phantom and a homogeneous phantom. The motivation is to mimic the human anatomy during a lung SBRT treatment and incorporate heterogeneities into the pre-treatment Quality Assurance process, where measured and calculated planar dose distributions are compared before the radiation treatment. Individual and combined field dosimetry has been performed for both fixed gantry angle (anterior to posterior) and planned gantry angle delivery. A gamma analysis has been performed for all beam arrangements. The measurements were obtained using the 2-D diode array MapCHECK 2™.
Show less - Date Issued
- 2015
- PURL
- http://purl.flvc.org/fau/fd/FA00004360
- Subject Headings
- Cancer -- Radiotherapy, Drug development -- Computer simulation, Image guided radiation therapy, Ion bombardment, Lung cancer -- Treatment, Medical physics, Monte Carlo method, Proton beams
- Format
- Document (PDF)
- Title
- Design of experiment of LCD watch using computer simulation.
- Creator
- Michalik, Marian., Florida Atlantic University, Mazuoz, Abdel Kader, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
- Abstract/Description
-
Computer modeling has become indispensable to the engineering process, from initially refining an idea with computer-aided tools to implementing the final steps in manufacturing a product. This thesis addresses the issue of design of a housing of LCD watch. An approach is developed to determine an optimal LCD watch design. An analysis and development of a design of experiment is performed to identify the major controllable variables to performed a statistical significance analysis on...
Show moreComputer modeling has become indispensable to the engineering process, from initially refining an idea with computer-aided tools to implementing the final steps in manufacturing a product. This thesis addresses the issue of design of a housing of LCD watch. An approach is developed to determine an optimal LCD watch design. An analysis and development of a design of experiment is performed to identify the major controllable variables to performed a statistical significance analysis on different shapes for LCD glass. A housing of LCD watch is modeled using Pro/Engineer (a parametric-based solid modeling system), and different shapes of LCD glass are tested using P3/Patran. A non-destructive static experiment is performed on the LCD. This experiment consisted of measuring the maximum displacement and equivalent stress. Taguchi method was used to analyze this experiment.
Show less - Date Issued
- 1995
- PURL
- http://purl.flvc.org/fcla/dt/15149
- Subject Headings
- Computer simulation, Taguchi methods (Quality control), Engineering design, Liquid crystal displays--Design and construction--Quality control, Liquid crystal devices--Design and construction--Quality control
- Format
- Document (PDF)
- Title
- Modeling and Control of Proton Exchange Membrane (PEM) Fuel Cell System.
- Creator
- Saengrung, Anucha, Zilouchian, Ali, Abtahi, Amir, Florida Atlantic University, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
This dissertation presents the design, implementation and application of soft computing methodologies to Proton Exchange Membrane (PEM) Fuel Cell systems. In the first part of the research work, two distinct approaches for the modeling and prediction of a commercial PEM fuel cell system are presented. Several Simulink models are constructed from the electrochemical models of the PEM fuel cells. The models have been simulated in three dimension (3-D) space to provide the visual understanding...
Show moreThis dissertation presents the design, implementation and application of soft computing methodologies to Proton Exchange Membrane (PEM) Fuel Cell systems. In the first part of the research work, two distinct approaches for the modeling and prediction of a commercial PEM fuel cell system are presented. Several Simulink models are constructed from the electrochemical models of the PEM fuel cells. The models have been simulated in three dimension (3-D) space to provide the visual understanding of fuel cell behaviors. In addition, two optimal predictive models, based on back-propagation (BP) and radial basis function (RBF) neural networks are developed. Experimental data as well as pre-processing data are utilized to determine the accuracy and speed of the proposed prediction algorithms. Extensive simulation results are presented to demonstrate the effectiveness of the proposed method on prediction of nonlinear input-output linear input-output mapping. In the second part of the study, the design and implementation of several fuzzy logic controllers (FLCs) as well as classical controllers are carried out. The proposed real-time controller design is based on the integration of sensory information, Labview programming, mathematical calculation, and expert knowledge of the process to yield optimum output power performance under variable load condition. The implementations of the proposed controllers are carried out for a commercial PEM fuel system at FA U Fuel Cell Laboratory. The performance of the proposed controllers pertaining to the oxygen (02) flow rate optimization as well as the actual fuel cell output power under a variable load bank are compared and investigated. It was found the Fuzzy Logic Controller design provide a simple and effective approach for the implementation of the fuel cell systems.
Show less - Date Issued
- 2008
- PURL
- http://purl.flvc.org/fau/fd/FA00012577
- Subject Headings
- Proton exchange membrane fuel cells--Design and construction, Proton exchange membrane fuel cells--Computer simulation, Fuel cells--Design and construction
- Format
- Document (PDF)