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The Effect Of Colloidal Stability On The Heat Transfer Characteristics Of Nanosilica Dispersed Fluids, Manoj Venkataraman Jan 2005

The Effect Of Colloidal Stability On The Heat Transfer Characteristics Of Nanosilica Dispersed Fluids, Manoj Venkataraman

Electronic Theses and Dissertations

Addition of nano particles to cooling fluids has shown marked improvement in the heat transfer capabilities. Nanofluids, liquids that contain dispersed nanoparticles, are an emerging class of fluids that have great potential in many applications. There is a need to understand the fundamental behavior of nano dispersed particles with respect to their agglomeration characteristics and how it relates to the heat transfer capability. Such an understanding is important for the development and commercialization of nanofluids. In this work, the stability of nano particles was studied by measuring the zeta potential of colloidal particles, particle concentration and size. Two different sizes …

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Solution Of Electromagnetic Scattering Parameters And Radiation Patterns Of Arbitrary Body Of Revolution Radiators, Wendell Brokaw Jan 2005

Solution Of Electromagnetic Scattering Parameters And Radiation Patterns Of Arbitrary Body Of Revolution Radiators, Wendell Brokaw

Electronic Theses and Dissertations

A novel full wave analysis method to determine the scattering parameters and the radiation field intensities of arbitrary Body of Revolution (BOR) radiators consisting of impenetrable media is explored through derived components of modal analysis and the method of moments (MoM). Modal excitation is utilized to excite the structural feed; allowing for a more accurate measure of the scattering parameters of the total structure as opposed to the use of external excitation sources. The derivation of the mode matching method introduces a novel approach to achieving a frequency independent coupling matrix that will reduce the computational requirements for iterations utilized …

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Real-Time Realistic Rendering And High Dynamic Range Image Display And Compression, Ruifeng Xu Jan 2005

Real-Time Realistic Rendering And High Dynamic Range Image Display And Compression, Ruifeng Xu

Electronic Theses and Dissertations

This dissertation focuses on the many issues that arise from the visual rendering problem. Of primary consideration is light transport simulation, which is known to be computationally expensive. Monte Carlo methods represent a simple and general class of algorithms often used for light transport computation. Unfortunately, the images resulting from Monte Carlo approaches generally suffer from visually unacceptable noise artifacts. The result of any light transport simulation is, by its very nature, an image of high dynamic range (HDR). This leads to the issues of the display of such images on conventional low dynamic range devices and the development of …

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A Methodology For Minimizing The Oscillations In Supply Chains Using System Dynamics And Genetic Algorithms, Ramamoorthy C.V.V. Lakkoju Jan 2005

A Methodology For Minimizing The Oscillations In Supply Chains Using System Dynamics And Genetic Algorithms, Ramamoorthy C.V.V. Lakkoju

Electronic Theses and Dissertations

Supply Chain Management (SCM) is a critically significant strategy that enterprises depend on to meet challenges that they face because of highly competitive and dynamic business environments of today. Supply chain management involves the entire network of processes from procurement of raw materials/services/technologies to manufacturing or servicing intermediate products/services to converting them into final products or services and then distributing and retailing them till they reach final customers. A supply chain network by nature is a large and complex, engineering and management system. Oscillations occurring in a supply chain because of internal and/or external influences and measures to be taken …

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Indoor Geo-Location And Tracking Of Mobile Autonomous Robot, Mahesh Ramamurthy Jan 2005

Indoor Geo-Location And Tracking Of Mobile Autonomous Robot, Mahesh Ramamurthy

Electronic Theses and Dissertations

The field of robotics has always been one of fascination right from the day of Terminator. Even though we still do not have robots that can actually replicate human action and intelligence, progress is being made in the right direction. Robotic applications range from defense to civilian, in public safety and fire fighting. With the increase in urban-warfare robot tracking inside buildings and in cities form a very important application. The numerous applications range from munitions tracking to replacing soldiers for reconnaissance information. Fire fighters use robots for survey of the affected area. Tracking robots has been limited to the …

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Microstructural And Mechanical Characterization Of Al-Al2o3 Nanocomposites Synthesized By High-Energy Milling, Balaji Prabhu Jan 2005

Microstructural And Mechanical Characterization Of Al-Al2o3 Nanocomposites Synthesized By High-Energy Milling, Balaji Prabhu

Electronic Theses and Dissertations

The twin objectives of the investigation were (i) to synthesize Al/Al2O3 metal matrix composites (MMCs) with uniform distribution of the Al2O3 reinforcement in the Al matrix and (ii) to evaluate the effect of volume fraction and size of the reinforcement on the mechanical behavior of MMCs. This was achieved by successful synthesis of Al-Al2O3 MMCs with volume fractions of 5, 10, 20, 30, and 50%, and particle sizes of 50 nm, 150 nm, and 5 µm of Al2O3 synthesized from blended component powders by a high-energy milling technique. A uniform distribution of the Al2O3 reinforcement in the Al matrix was …

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Analysis And Design Of A Modular Solar-Fed Fault-Tolerant Power System With Maximum Power Point Tracking, Hussam Al-Atrash Jan 2005

Analysis And Design Of A Modular Solar-Fed Fault-Tolerant Power System With Maximum Power Point Tracking, Hussam Al-Atrash

Electronic Theses and Dissertations

Solar power is becoming ever more popular in a variety of applications. It is particularly attractive because of its abundance, renewability, and environment friendliness. Solar powered spacecraft systems have ever-expanding loads with stringent power regulation specifications. Moreover, they require a light and compact design of their power system. These constraints make the optimization of power harvest from solar arrays a critical task. Florida Power Electronics Center (FPEC) at UCF set to develop a modular fault-tolerant power system architecture for space applications. This architecture provides a number of very attractive features including Maximum Power Point Tracking (MPPT) and uniform power stress …

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Scene Monitoring With A Forest Of Cooperative Sensors, Omar Javed Jan 2005

Scene Monitoring With A Forest Of Cooperative Sensors, Omar Javed

Electronic Theses and Dissertations

In this dissertation, we present vision based scene interpretation methods for monitoring of people and vehicles, in real-time, within a busy environment using a forest of co-operative electro-optical (EO) sensors. We have developed novel video understanding algorithms with learning capability, to detect and categorize people and vehicles, track them with in a camera and hand-off this information across multiple networked cameras for multi-camera tracking. The ability to learn prevents the need for extensive manual intervention, site models and camera calibration, and provides adaptability to changing environmental conditions. For object detection and categorization in the video stream, a two step detection …

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Development Of A Graphical User Interface For Cal3qhc Called Calqcad, Sheetal Gawalpanchi Jan 2005

Development Of A Graphical User Interface For Cal3qhc Called Calqcad, Sheetal Gawalpanchi

Electronic Theses and Dissertations

One of the major sources of air pollution in the United States metropolitan areas is due to automobiles. With the huge growth of motor vehicles and, greater dependence on them, air pollution problems have been aggravated. According to the EPA, nearly 95% of carbon monoxide (CO ) (EPA 1999) in urban areas comes from mobile sources, of which 51% is contributed by on road vehicles. It is well known fact that, carbon monoxide is one of the major mobile source pollutants and CO has detrimental effects on the human health. Carbon monoxide is the result of mainly incomplete combustion of …

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Ascertaining The Growth Of A Company A System Dynamics Approach, Fakir Mohideen Noor Mohideen Jan 2005

Ascertaining The Growth Of A Company A System Dynamics Approach, Fakir Mohideen Noor Mohideen

Electronic Theses and Dissertations

Business is often about creating change for other businesses. At times, these changes affect only the company and at other times they affect the entire industry. There is a time in the life of a business when its fundamental way of functioning is questioned and is subjected to change. That change can mean an opportunity to rise to new heights, or it might even signal the beginning of the end. This fundamental change in any business is known as an inflection point. Understanding the nature of its inflection point and responding to that point suitably will help to safeguard a …

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Enhancing Message Privacy In Wired Equivalent Privacy., Darshan Purandare Jan 2005

Enhancing Message Privacy In Wired Equivalent Privacy., Darshan Purandare

Electronic Theses and Dissertations

The 802.11 standard defines the Wired Equivalent Privacy (WEP) and encapsulation of data frames. It is intended to provide data privacy to the level of a wired network. WEP suffered threat of attacks from hackers owing to certain security shortcomings in the WEP protocol. Lately, many new protocols like WiFi Protected Access (WPA), WPA2, Robust Secure Network (RSN) and 802.11i have come into being, yet their implementation is fairly limited. Despite its shortcomings one cannot undermine the importance of WEP as it still remains the most widely used system and we chose to address certain security issues and propose some …

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Rollback-Able Random Number Generators For The Synchronous Parallel Environment For Emulation And Discrete-Event Simulation (Spe, Ramaswamy Karthik Narayanan Jan 2005

Rollback-Able Random Number Generators For The Synchronous Parallel Environment For Emulation And Discrete-Event Simulation (Spe, Ramaswamy Karthik Narayanan

Electronic Theses and Dissertations

Random Numbers form the heart and soul of a discrete-event simulation system. There are few situations where the actions of the entities in the process being simulated can be completely predicted in advance. The real world processes are more probabilistic than deterministic. Hence, such chances are represented in the system by using various statistical models, like random number generators. These random number generators can be used to represent a various number of factors, such as length of the queue. However, simulations have grown in size and are sometimes required to run on multiple machines, which share the various methods or …

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Creating Geo-Specific Road Databases From Aerial Photos For Driving Simulation, Dahai Guo Jan 2005

Creating Geo-Specific Road Databases From Aerial Photos For Driving Simulation, Dahai Guo

Electronic Theses and Dissertations

Geo-specific road database development is important to a driving simulation system and a very labor intensive process. Road databases for driving simulation need high resolution and accuracy. Even though commercial software is available on the market, a lot of manual work still has to be done when the road crosssectional profile is not uniform. This research deals with geo-specific road databases development, especially for roads with non-uniform cross sections. In this research, the United States Geographical Survey (USGS) road information is used with aerial photos to accurately extract road boundaries, using image segmentation and data compression techniques. Image segmentation plays …

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A New Paradigm Of Modeling Watershed Water Quality, Fan Zhang Jan 2005

A New Paradigm Of Modeling Watershed Water Quality, Fan Zhang

Electronic Theses and Dissertations

Accurate models to reliably predict sediment and chemical transport in watershed water systems enhance the ability of environmental scientists, engineers and decision makers to analyze the impact of contamination problems and to evaluate the efficacy of alternative remediation techniques and management strategies prior to incurring expense in the field. This dissertation presents the conceptual and mathematical development of a general numerical model simulating (1) sediment and reactive chemical transport in river/stream networks of watershed systems; (2) sediment and reactive chemical transport in overland shallow water of watershed systems; and (3) reactive chemical transport in three-dimensional subsurface systems. Through the decomposition …

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Assessment Framework For The Evaluation And Prioritization Of University Technologies For Licensing And Commercialization, Ahmad D. Rahal Jan 2005

Assessment Framework For The Evaluation And Prioritization Of University Technologies For Licensing And Commercialization, Ahmad D. Rahal

Electronic Theses and Dissertations

US corporations have long recognized university related scientific research as an important source of long term economic growth and technological innovation. This dynamic involvement with industry has drastically increased the university technology transfer and licensing activities, and has stretched the human and financial resources of Technology Management and Licensing Offices of many US universities. This research provides a mechanism that can aid in the complex process of properly assessing university-owned technologies and intellectual properties, to identify those with licensing and commercialization potential for the pursuit of truly important breakthrough discoveries. This research focuses on the university technology licensing and commercialization …

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Designing A Document Delivery System For Ucf S Interlibrary Loan Department, Abha Y. Trivedi Jan 2005

Designing A Document Delivery System For Ucf S Interlibrary Loan Department, Abha Y. Trivedi

Electronic Theses and Dissertations

Interlibrary Loan entails obtaining copies of library materials not found in the library's collection on behalf of the library's patrons (borrowing), as well as providing copies of library materials requested by other libraries (lending). The dynamic nature of today's library environment is well illustrated by the rapid changes occurring in the role of interlibrary loan. The vision statement of the University of Central Florida Library is: The library performs a central role of adding value to information for the academic community by creatively improving and providing information resources and services. The library strives to create an environment that encourages the …

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Frequency Domain Independent Component Analysis Applied To Wireless Communications Over Frequency-Selective Channels, Yuan Liu Jan 2005

Frequency Domain Independent Component Analysis Applied To Wireless Communications Over Frequency-Selective Channels, Yuan Liu

Electronic Theses and Dissertations

In wireless communications, frequency-selective fading is a major source of impairment for wireless communications. In this research, a novel Frequency-Domain Independent Component Analysis (ICA-F) approach is proposed to blindly separate and deconvolve signals traveling through frequency-selective, slow fading channels. Compared with existing time-domain approaches, the ICA-F is computationally efficient and possesses fast convergence properties. Simulation results confirm the effectiveness of the proposed ICA-F. Orthogonal Frequency Division Multiplexing (OFDM) systems are widely used in wireless communications nowadays. However, OFDM systems are very sensitive to Carrier Frequency Offset (CFO). Thus, an accurate CFO compensation technique is required in order to achieve acceptable …

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Qos In Cognitive Packet Networks: Adaptive Routing, Flow And Congestion Control, Pu Su Jan 2005

Qos In Cognitive Packet Networks: Adaptive Routing, Flow And Congestion Control, Pu Su

Electronic Theses and Dissertations

With the emergence of various applications that have different Quality of Service (QoS) requirements, the capability of a network to support QoS becomes more and more important and necessary. This dissertation explores QoS in Cognitive Packet Networks (CPN) by using adaptive routing, flow and congestion control. We present a detailed description and analysis of our proposed routing algorithms based on single and multiple QoS constraints. An online estimation of packet loss rate over a path is introduced. We implement and evaluate the adaptive routing scheme in an experimental CPN test-bed. Our experiments support our claims that the users can achieve …

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Access Games: A Game Theoretic Framework For Fair Bandwidth Sharing In Distributed Systems, Sudipta Rakshit Jan 2005

Access Games: A Game Theoretic Framework For Fair Bandwidth Sharing In Distributed Systems, Sudipta Rakshit

Electronic Theses and Dissertations

In this dissertation, the central objective is to achieve fairness in bandwidth sharing amongst selfish users in a distributed system. Because of the inherent contention-based nature of the distributed medium access and the selfishness of the users, the distributed medium access is modeled as a non-cooperative game; designated as the Access Game. A p-CSMA type medium access scenario is proposed for all the users. Therefore, in the Access Game, each user has two actions to choose from: "transmit" and "wait". The outcome of the Access Game and payoffs to each user depends on the actions taken by all the users. …

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Debris Tracking In A Semistable Background, Karthikkalathi Vanumamalai Jan 2005

Debris Tracking In A Semistable Background, Karthikkalathi Vanumamalai

Electronic Theses and Dissertations

Object Tracking plays a very pivotal role in many computer vision applications such as video surveillance, human gesture recognition and object based video compressions such as MPEG-4. Automatic detection of any moving object and tracking its motion is always an important topic of computer vision and robotic fields. This thesis deals with the problem of detecting the presence of debris or any other unexpected objects in footage obtained during spacecraft launches, and this poses a challenge because of the non-stationary background. When the background is stationary, moving objects can be detected by frame differencing. Therefore there is a need for …

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Resource Allocation Schemes And Performance Evaluation Models For Wavelength Division Multiplexed Optical Networks, Mounire El Houmaidi Jan 2005

Resource Allocation Schemes And Performance Evaluation Models For Wavelength Division Multiplexed Optical Networks, Mounire El Houmaidi

Electronic Theses and Dissertations

Wavelength division multiplexed (WDM) optical networks are rapidly becoming the technology of choice in network infrastructure and next-generation Internet architectures. WDM networks have the potential to provide unprecedented bandwidth, reduce processing cost, achieve protocol transparency, and enable efficient failure handling. This dissertation addresses the important issues of improving the performance and enhancing the reliability of WDM networks as well as modeling and evaluating the performance of these networks. Optical wavelength conversion is one of the emerging WDM enabling technologies that can significantly improve bandwidth utilization in optical networks. A new approach for the sparse placement of full wavelength converters based …

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Remarks On Topological Properties Of Boehmians, Józef Burzyk, Piotr Mikusinski, Dennis Nemzer Jan 2005

Remarks On Topological Properties Of Boehmians, Józef Burzyk, Piotr Mikusinski, Dennis Nemzer

Faculty Bibliography 2000s

Spaces of Boehmians are equipped with a topology defined in a canonical way, but properties of that topology can differ significantly for different spaces of Boehmians. First we discuss an example of a space of Boehmians with trivial dual space. Then we show that the space of periodic Boehmians has a nontrivial dual space, but the topology is not locally convex. Finally, we give an example of a space of Boehmians that is a locally convex space.

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Addition Laws In Introductory Physics, C. J. Efthimiou, R. A. Llewellyn Jan 2005

Addition Laws In Introductory Physics, C. J. Efthimiou, R. A. Llewellyn

Faculty Bibliography 2000s

We propose a unified approach to addition of some physical quantities (among which resistors and capacitors are the most well known) that are usually encountered in introductory physics such that the formulae required to solve problems are always simply additive. This approach has the advantage of being consistent with the intuition of students. To demonstrate the effectiveness of our approach, we propose and solve several problems. We hope that this paper can serve as a resource paper for problems on the subject.

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Effects Of Content Augmentation Strategies In An Instructional Virtual Environment, Roger Hamilton Jan 2005

Effects Of Content Augmentation Strategies In An Instructional Virtual Environment, Roger Hamilton

Electronic Theses and Dissertations

Content augmentation strategies (CAS) are instructional methods which specify the overlaying of content objects by content augmentation objects in order to increase the effectiveness and efficiency of instruction. The goals of this research were to build a comprehensive framework around CASs, determine the experimental effects of CASs in an instructional virtual environment (VE), and make recommendations regarding the employment and further study of CASs in instructional virtual environments. The VE experiment examined the effectiveness and efficiency impact of six different content augmentation strategies which overlayed different content augmentation objects onto four immersive VE scenarios. Sixty university students, 40 men and …

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Development Of An Artificial Neural Networks Model To Estimate Delay Using Toll Plaza Transaction Data, Aparna Muppidi Jan 2005

Development Of An Artificial Neural Networks Model To Estimate Delay Using Toll Plaza Transaction Data, Aparna Muppidi

Electronic Theses and Dissertations

In spite of the most up-to-date investigation of the relevant techniques to analyze the traffic characteristics and traffic operations at a toll plaza, there has not been any note worthy explorations evaluating delay from toll transaction data and using Artificial Neural Networks (ANN) at a toll plaza. This thesis lays an emphasis on the application of ANN techniques to estimate the total vehicular delay according to the lane type at a toll plaza. This is done to avoid the laborious task of extracting data from the video recordings at a toll plaza. Based on the lane type a general methodology …

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Neural Network Trees And Simulation Databases: New Approaches For Signalized Intersection Crash Classification And Prediction, Piyush Nawathe Jan 2005

Neural Network Trees And Simulation Databases: New Approaches For Signalized Intersection Crash Classification And Prediction, Piyush Nawathe

Electronic Theses and Dissertations

Intersection related crashes form a significant proportion of the crashes occurring on roadways. Many organizations such as the Federal Highway Administration (FHWA) and American Association of State Highway and Transportation Officials (AASHTO) are considering intersection safety improvement as one of their top priority areas. This study contributes to the area of safety of signalized intersections by identifying the traffic and geometric characteristics that affect the different types of crashes. The first phase of this thesis was to classify the crashes occurring at signalized intersections into rear-end, angle, turn and sideswipe crash types based on the traffic and geometric properties of …

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Optimizing The Performance Of As-Manufactured Grazing Incidence X-Ray Telescopes Using Mosaic Detector Arrays, Martina Atanassova Jan 2005

Optimizing The Performance Of As-Manufactured Grazing Incidence X-Ray Telescopes Using Mosaic Detector Arrays, Martina Atanassova

Electronic Theses and Dissertations

The field of X-ray astronomy is only forty (43) years old, and grazing incidence X-ray telescopes have only been conceived and designed for a little over fifty (50) years. The Wolter Type I design is particularly well suited for stellar astronomical telescopes (very small field-of-view). The first orbiting X-ray observatory, HEAO-1 was launched in 1977, a mere twenty-eight (28) years ago. Since that time large nested Wolter Type I X-ray telescopes have been designed, build, and launched by the European Space Agency (ROSAT) and NASA (the Chandra Observatory). Several smaller grazing incidence telescopes have been launched for making solar observations …

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University Of Central Florida 2004-2005 Fact Book, University Of Central Florida Jan 2005

University Of Central Florida 2004-2005 Fact Book, University Of Central Florida

Historical Fact Book and Enrollment

Historical fact book and enrollment data for the University of Central Florida.

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Home School Versus Other Applicants To Postsecondary Institutions: Admission Policies And In-Depth Analysis, Rebecca Lynn Ashford Jan 2005

Home School Versus Other Applicants To Postsecondary Institutions: Admission Policies And In-Depth Analysis, Rebecca Lynn Ashford

Electronic Theses and Dissertations

In this study, 94 colleges and universities in Florida were surveyed to determine what their admission policies were for home school applicants. Forty-six colleges responded to the survey. The results of the survey were analyzed to determine if there was a pattern of acceptance based on institution type--public, private, or proprietary. Further, the admission policies were analyzed to determine the extent to which they complied with the National Center for Home Education's (NCHE) recommend college admission policies for home school applicants. The researcher found that public colleges were more likely to accept home school students than were private colleges. Also, …

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Coverage Path Planning And Control For Autonomous Mobile Robots, Mohanakrishnan Balakrishnan Jan 2005

Coverage Path Planning And Control For Autonomous Mobile Robots, Mohanakrishnan Balakrishnan

Electronic Theses and Dissertations

Coverage control has many applications such as security patrolling, land mine detectors, and automatic vacuum cleaners. This Thesis presents an analytical approach for generation of control inputs for a non-holonomic mobile robot in coverage control. Neural Network approach is used for complete coverage of a given area in the presence of stationary and dynamic obstacles. A complete coverage algorithm is used to determine the sequence of points. Once the sequences of points are determined a smooth trajectory characterized by fifth order polynomial having second order continuity is generated. And the slope of the curve at each point is calculated from …

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