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MITOCHONDRIAL GENETIC DIVERSITY OF THE RED-TAILED MONKEY, CERCOPITHECUS ASCANIUS, IN AFRICAN RAINFORESTS
Title
MITOCHONDRIAL GENETIC DIVERSITY OF THE RED-TAILED MONKEY, CERCOPITHECUS ASCANIUS, IN AFRICAN RAINFORESTS.
Creator
Dutra, Vitor Daniel, Detwiler, Kate M., Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
Abstract/Description
Cercopithecus ascanius is an African primate species encompassing five geographic types with unresolved taxonomy. Recent publications have analyzed C. ascanius genetic diversity and taxonomy; however, few publications have addressed the genetic diversity and phylogenetic relationships of C. ascanius from wild populations. My objectives for this thesis were to determine mtDNA diversity within the C. Ascanius species and investigate C. ascanius genetic structure. Results from this thesis...
Show moreCercopithecus ascanius is an African primate species encompassing five geographic types with unresolved taxonomy. Recent publications have analyzed C. ascanius genetic diversity and taxonomy; however, few publications have addressed the genetic diversity and phylogenetic relationships of C. ascanius from wild populations. My objectives for this thesis were to determine mtDNA diversity within the C. Ascanius species and investigate C. ascanius genetic structure. Results from this thesis support findings from previous studies wherein C. ascanius depicted high mitochondrial diversity and all C. ascanius subspecies form a monophyletic clade within the Cercopithecus genus. Analyzing additional samples of C. ascanius monkeys will strengthen molecular diversity estimation and clarify genetic structure within the C. ascanius lineage.
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Date Issued
2023
PURL
http://purl.flvc.org/fau/fd/FA00014325
Subject Headings
Mitochondrial DNA, Cercopithecus ascanius, Genetics, Phylogeny
Format
Document (PDF)
Mitochondrial regulation pathways in the lens: pink1/parkin- and bnip3l-mediated mechanisms
Title
Mitochondrial regulation pathways in the lens: pink1/parkin- and bnip3l-mediated mechanisms.
Creator
Aktan, Kerem, Kantorow, Marc, Florida Atlantic University, Charles E. Schmidt College of Medicine, Department of Biomedical Science
Abstract/Description
The mitochondrion is the powerhouse of the cell. Therefore, it is critical to the homeostasis of the cell that populations of mitochondria that are damaged or in excess are degraded. The process of targeted elimination of damaged or excess mitochondria by autophagy is called mitophagy. In this report, analysis of the mitophagy regulators PINK1/PARKIN and BNIP3L and their roles are assessed in the lens. PARKIN, an E3 ubiquitin ligase, has been shown to play a role in directing damaged...
Show moreThe mitochondrion is the powerhouse of the cell. Therefore, it is critical to the homeostasis of the cell that populations of mitochondria that are damaged or in excess are degraded. The process of targeted elimination of damaged or excess mitochondria by autophagy is called mitophagy. In this report, analysis of the mitophagy regulators PINK1/PARKIN and BNIP3L and their roles are assessed in the lens. PARKIN, an E3 ubiquitin ligase, has been shown to play a role in directing damaged mitochondria for degradation. While BNIP3L, an outer mitochondrial membrane protein, increases in expression in response to excess mitochondria and organelle degradation during cellular differentiation. We have shown that PARKIN is both induced and translocates from the cytoplasm to the mitochondria in human epithelial lens cells upon oxidative stress exposure. In addition, our findings also show that overexpression of BNIP3L causes premature clearance of mitochondria and other organelles, while loss of BNIP3L results in lack of clearance. Prior to this work, PARKIN mediated mitophagy had not been shown to act as a protective cellular response to oxidative stress in the lens. This project also resulted in the novel finding that BNIP3L-mediated mitophagy mechanisms are required for targeted organelle degradation in the lens.
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Date Issued
2015
PURL
http://purl.flvc.org/fau/fd/FA00004427, http://purl.flvc.org/fau/fd/FA00004427
Subject Headings
Cellular signal transduction, Eye -- Diseases -- Etiology, Mitochondrial pathology, Mitophagy, Molecular chaperones, Oxidative stress -- Prevention, Protein folding
Format
Document (PDF)
mixed integer nonlinear programming model to optimize the use of aircraft deicing and anti-icing fluids
Title
A mixed integer nonlinear programming model to optimize the use of aircraft deicing and anti-icing fluids.
Creator
Ornitz, Scott E., College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
Abstract/Description
A detailed study is proposed for understanding the use of aircraft deicing and anti-icing fluids (ADAF) and optimal use of these fluids in airport operations. A detailed literature review of past and current technologies is conducted and possible opportunities to improve the use of ADAF and relevant recommendations are derived. Mathematical optimization models (e.g. MINLP with binary variables) based on a variety of objectives, which deal with exhaustive sets of system constraints are...
Show moreA detailed study is proposed for understanding the use of aircraft deicing and anti-icing fluids (ADAF) and optimal use of these fluids in airport operations. A detailed literature review of past and current technologies is conducted and possible opportunities to improve the use of ADAF and relevant recommendations are derived. Mathematical optimization models (e.g. MINLP with binary variables) based on a variety of objectives, which deal with exhaustive sets of system constraints are formulated, developed and applied to case studies. One real-life case study area which routinely carries out aircraft deicing is used for testing the mathematical optimization formulations for optimal use of fluids under budgetary and environmental compliance constraints. Based on the recommendations from one of the best optimization model formulations it is hoped that it will be used for a real-time implementation. Results from these formulations show the models to be robust and applicable.
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Date Issued
2009
PURL
http://purl.flvc.org/FAU/192987
Subject Headings
Deicing chemicals, Testing, Airplanes, Ice prevention, Programming (Mathematics)
Format
Document (PDF)
Mixed light imaging system for recording bioluminescence behaviours
Title
Mixed light imaging system for recording bioluminescence behaviours.
Creator
Widder, Edith A., Harbor Branch Oceanographic Institute
Date Issued
1992
PURL
http://purl.flvc.org/fau/fd/FA00007217
Subject Headings
Bioluminescence, Underwater imaging systems, Video recordings, Copepoda
Format
Document (PDF)
Mixed Method of Health Literacy and Diabetes Self- Management Among Saudi Adults with Type 2 Diabetes Mellitus
Title
Mixed Method of Health Literacy and Diabetes Self- Management Among Saudi Adults with Type 2 Diabetes Mellitus.
Creator
Almashni, Ibtisam Y., Hain, Debra, Florida Atlantic University, Christine E. Lynn College of Nursing, Christine E. Lynn College of Nursing
Abstract/Description
The worldwide threat of Diabetes Mellitus (DM) has been increasing rapidly, and is now an estimated 463 million, of which 55 million people originate from Middle East and Nort African (“MENA”) region (international Diabetes Federation [“IDF’], 2020). In Saudi Arabia, the prevalence of diabetes has roughly reached a ten-fold increase in the past three decades, placing Saudi Arabia’s incidence as one of the highest globally (Almubark et al., 2022). The purpose of the study was to examine the...
Show moreThe worldwide threat of Diabetes Mellitus (DM) has been increasing rapidly, and is now an estimated 463 million, of which 55 million people originate from Middle East and Nort African (“MENA”) region (international Diabetes Federation [“IDF’], 2020). In Saudi Arabia, the prevalence of diabetes has roughly reached a ten-fold increase in the past three decades, placing Saudi Arabia’s incidence as one of the highest globally (Almubark et al., 2022). The purpose of the study was to examine the relationship between health and diabetes self-management among Saudi adults with Type 2 Diabetes Mellitus (T2DM). The study further aimed to explore how Saudi adult with T2DM seek and utilize diabetes knowledge to self-manage their diabetes. The study was guided by Leininger’s Culture Care Diversity and Universality Theory (2002). Leininger’s Sunrise Enabler- Model provided a framework to explore the various factors that affect diabetes self-management through a cultural lens. This model provides a comprehensive understanding pf multiple factors influencing diabetes self-management. A sample of 66 Saudi adults with T2DM aged 40-61 and older was recruited from diabetes center and Primary Healthcare Center (PHCC) at National Guard Hospital King Abdulaziz Medical City Jeddah, Saudi Arabia. A Parallel Mixed Method (PPM) design was applied, using semi-structured interviews, Diabetes Self-management Questionnaire (DSMQ), Short Test of Functional Health Literacy in Adult (S-TOFHLA), and sociodemographic surveys.
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Date Issued
2023
PURL
http://purl.flvc.org/fau/fd/FA00014326
Subject Headings
Diabetes, Health literacy, Self Management, Saudi Arabians, Health education
Format
Document (PDF)
Mixedschooling and its possible significance in a tropical western Atlantic parrotfish and surgeonfish
Title
Mixedschooling and its possible significance in a tropical western Atlantic parrotfish and surgeonfish.
Creator
Alevizon, W. S., Harbor Branch Oceanographic Institute
Date Issued
1976
PURL
http://purl.flvc.org/fau/fd/FA00007101
Subject Headings
Parrotfishes, Surgeonfishes, Fishes--Schooling, Acanthurus
Format
Document (PDF)
Mixing Chemicals, 1967
Title
Mixing Chemicals, 1967.
Creator
James G. McCulla
Date Issued
1967
PURL
http://purl.flvc.org/fcla/dt/2795872
Subject Headings
Florida Atlantic University -- History, Florida Atlantic University -- Students
Format
Image (JPEG2000)
Mixing Chemicals, 1967
Title
Mixing Chemicals, 1967.
Creator
James G. McCulla
Date Issued
1967
PURL
http://purl.flvc.org/fcla/dt/2795874
Subject Headings
Florida Atlantic University -- History, Florida Atlantic University -- Students
Format
Image (JPEG2000)
Mixing properties in human behavioral style and time dependencies in behavior identification: The modeling and application of a universal dynamical law
Title
Mixing properties in human behavioral style and time dependencies in behavior identification: The modeling and application of a universal dynamical law.
Creator
Selz, Karen A., Florida Atlantic University, Vallacher, Robin R.
Abstract/Description
Human subjects perform simple, relatively unconstrained, game-like computer tasks. "Meso-level" measures of behavioral complexity and time-dependencies (including entropies, grammatical complexity estimates and run statistics) are derived and computed. Individual behavioral differences in the resulting complexity measures are robust and, in a temporal-forcing paradigm, are statistically significantly related to the same individual's scores on a range of personality and demographic variables....
Show moreHuman subjects perform simple, relatively unconstrained, game-like computer tasks. "Meso-level" measures of behavioral complexity and time-dependencies (including entropies, grammatical complexity estimates and run statistics) are derived and computed. Individual behavioral differences in the resulting complexity measures are robust and, in a temporal-forcing paradigm, are statistically significantly related to the same individual's scores on a range of personality and demographic variables. Through an experimental manipulation and the statistical selection of maximally useful predictor sets personality and demographic variables are united in a "macro-level" temperament typology, based on "micro-level" behavioral tendencies. Further, I can compute a parameter value of a one dimensional dynamical system, the symmetric tent map, matched to the symbol sequence "meso-level" parities of the subject. When this parameter is used in the iterated map, it produces sequences that are of the same autocorrelation "category" and share much of the fine structure of the autocorrelograms of the subjects to which the map parameter had been matched.
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Date Issued
1992
PURL
http://purl.flvc.org/fcla/dt/12306
Subject Headings
Rape victims, Attribution (Social psychology)
Format
Document (PDF)
MMO gaming culture: an online gaming family
Title
MMO gaming culture: an online gaming family.
Creator
Perez, Michael, Harris, Michael S., Florida Atlantic University, Dorothy F. Schmidt College of Arts and Letters, Department of Anthropology
Abstract/Description
This study examines the social organization of Gaiscíoch, a large online gaming community that exists within the simulated world of a massively multiplayer online role playing game (MMORPG). It provides an ethnographic account of an online gaming community that is open to any player without skill or time commitment requirements, but still maintains high status within the game world. This project identifies eight elements that make this inclusive, friendly, and casual community successful in...
Show moreThis study examines the social organization of Gaiscíoch, a large online gaming community that exists within the simulated world of a massively multiplayer online role playing game (MMORPG). It provides an ethnographic account of an online gaming community that is open to any player without skill or time commitment requirements, but still maintains high status within the game world. This project identifies eight elements that make this inclusive, friendly, and casual community successful in virtual worlds that tend to be dominated by communities that have a competitive, strict, and exclusive approach to online gaming (social interaction, code of values, leadership, rank system, events, community building, population size, gameplay). Lastly, this project briefly inquires about the nature of the border between the virtual and the physical and establishes that gamers can be considered pseudo-border-inhabitants that are in control of the community they place adjacent to them in the cyber world.
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Date Issued
2015
PURL
http://purl.flvc.org/fau/fd/FA00004399, http://purl.flvc.org/fau/fd/FA00004399
Subject Headings
Cyberspace -- Social aspects, Fantasy games -- Social aspects, Internet games -- Social aspects, Role playing -- Social aspects, Video games -- Social aspects
Format
Document (PDF)
Mnucho Wsimcho
Title
Mnucho Wsimcho.
Creator
Russotto, Henry A.
Date Issued
1907
PURL
http://purl.flvc.org/FCLA/DT/71592
Subject Headings
Piano
Format
Document (PDF)
Mobbing, burnout, and religious coping styles among Protestant clergy
Title
Mobbing, burnout, and religious coping styles among Protestant clergy: a structural equation model and its implications for counselors.
Creator
Vensel, Steven R., College of Education, Department of Counselor Education
Abstract/Description
This study investigates the relationship between mobbing, burnout, and religious coping styles among Protestant clergy. Mobbing is an emotionally abusive workplace behavior and is defined as the prolonged malacious harassment of a coworker by a group of other members of an organization to secure the removal from the organization of the one who is targeted. Mobbing has only recently become a focus of attention in the US. To date, there are no known studies investigating mobbing in the...
Show moreThis study investigates the relationship between mobbing, burnout, and religious coping styles among Protestant clergy. Mobbing is an emotionally abusive workplace behavior and is defined as the prolonged malacious harassment of a coworker by a group of other members of an organization to secure the removal from the organization of the one who is targeted. Mobbing has only recently become a focus of attention in the US. To date, there are no known studies investigating mobbing in the workplace setting of the church. The broad purpose of this study is to determine if Protestant pastors experience mobbing, how they are affected by it, and how they cope with it. Four religious coping styles - Self-directing, Collaborative, Deferring, and Surrender to God - are investigated to determine how coping styles of religious individuals function in mediating the effect of mobbing or burnout. Burnout is assessed throught he Maslach Burnout Inventory and measures emotional exhaustion, depersonalization, and reduced personal accomplishment. This study utilizes Structural Equation Modeling (SEM) and presents two models of mediational analysis.... The results of analysis indicate that Protestant clergy do experience being mobbed which results in emotional exhaustion and depersonalization. Clergy with a self-directing coping style experience more burnout than do those who utilize a surrender to God style. Differences in indirect effects between models were noted. The implications to theory and practice are discussed.
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Date Issued
2012
PURL
http://purl.flvc.org/FAU/3356893
Subject Headings
Psychologists of religion, Stress management, Pastoral counseling, Stress (Psychology), Burn out (Psychology), Clergy, Job stress, Work environment, Psychological aspects, Violence in the workplace
Format
Document (PDF)
Mobile agent and its application in distributed systems
Title
Mobile agent and its application in distributed systems.
Creator
Khumanthem, Rajesh Singh., Florida Atlantic University, Wu, Jie, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description
Distributed computing has a lot of complex distributed control functions like mutual exclusion, data replication, load sharing, check pointing etc. The present study introduces two novel ways to address some of the issues in the first two areas---mutual exclusion and data replication with the use of mobile agent technology. This research work deals with analyzing the various advantages that Mobile Agent Technology provides and how its use can impact the design and development of distributed...
Show moreDistributed computing has a lot of complex distributed control functions like mutual exclusion, data replication, load sharing, check pointing etc. The present study introduces two novel ways to address some of the issues in the first two areas---mutual exclusion and data replication with the use of mobile agent technology. This research work deals with analyzing the various advantages that Mobile Agent Technology provides and how its use can impact the design and development of distributed system. The primary focus of this study is to present a clear view of the evolutionary path that will take us from the current technology to widespread use of mobile code and agents within the next few years.
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Date Issued
2003
PURL
http://purl.flvc.org/fcla/dt/13032
Subject Headings
Electronic data processing--Distributed processing, Mobile agents (Computer software)
Format
Document (PDF)
Mobile docking of REMUS-100 equipped with USBL-APS to an unmanned surface vehicle: a performance feasibility study
Title
Mobile docking of REMUS-100 equipped with USBL-APS to an unmanned surface vehicle: a performance feasibility study.
Creator
Miranda, Mario II, Beaujean, Pierre-Philippe, Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description
The overall objective of this work is to evaluate the ability of homing and docking an unmanned underwater vehicle (Hydroid REMUS 100 UUV) to a moving unmanned surface vehicle (Wave-Adaptive Modular Surface Vehicle USV) using a Hydroid Digital Ultra-Short Baseline (DUSBL) acoustic positioning system (APS), as a primary navigation source. An understanding of how the UUV can rendezvous with a stationary USV first is presented, then followed by a moving USV. Inherently, the DUSBL-APS is...
Show moreThe overall objective of this work is to evaluate the ability of homing and docking an unmanned underwater vehicle (Hydroid REMUS 100 UUV) to a moving unmanned surface vehicle (Wave-Adaptive Modular Surface Vehicle USV) using a Hydroid Digital Ultra-Short Baseline (DUSBL) acoustic positioning system (APS), as a primary navigation source. An understanding of how the UUV can rendezvous with a stationary USV first is presented, then followed by a moving USV. Inherently, the DUSBL-APS is susceptible to error due to the physical phenomena of the underwater acoustic channel (e.g. ambient noise, attenuation and ray refraction). The development of an APS model has allowed the authors to forecast the UUV’s position and the estimated track line of the USV as determined by the DUSBL acoustic sensor. In this model, focus is placed on three main elements: 1) the acoustic channel and sound ray refraction when propagating in an in-homogeneous medium; 2) the detection component of an ideal DUSBL-APS using the Neyman-Pearson criterion; 3) the signal-to-noise ratio (SNR) and receiver directivity impact on position estimation. The simulation tool is compared against actual open water homing results in terms of the estimated source position between the simulated and the actual USBL range and bearing information.
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Date Issued
2014
PURL
http://purl.flvc.org/fau/fd/FA00004140, http://purl.flvc.org/fau/fd/FA00004140
Subject Headings
Adaptive signal processing, Mobile robots, Underwater acoustic telemetry
Format
Document (PDF)
Mobile Modernity: Transportation in the works of F. Scott Fitzgerald and Ernest Hemingway
Title
Mobile Modernity: Transportation in the works of F. Scott Fitzgerald and Ernest Hemingway.
Creator
Johnston, Carrie E., Furman, Andrew, Florida Atlantic University
Abstract/Description
A central paradox in modernism is its disdain for mass culture, despite mass culture 's undeniable presence in modernist literature. American authors writing during the early twentieth century tried to establish themselves as "highbrow" by leaving the U.S. and traveling to Europe. In doing so, they created a particular aesthetic characterized by depictions of the transportation that facilitated this travel. These depictions reveal modernism's dependence on mass culture, and more importantly,...
Show moreA central paradox in modernism is its disdain for mass culture, despite mass culture 's undeniable presence in modernist literature. American authors writing during the early twentieth century tried to establish themselves as "highbrow" by leaving the U.S. and traveling to Europe. In doing so, they created a particular aesthetic characterized by depictions of the transportation that facilitated this travel. These depictions reveal modernism's dependence on mass culture, and more importantly, create a space in which modernist authors can negotiate what was once a choice between high or low culture, exile or tourist, and ultimately, modernism or mass culture. Analyzing the car and train scenes in F. Scott Fitzgerald's Tender is the Night and Ernest Hemingway's The Sun Also Rises reveals the hybrid spaces made available to these authors through transportation.
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Date Issued
2008
PURL
http://purl.flvc.org/fau/fd/FA00000930
Subject Headings
Fitzgerald, F Scott--(Francis Scott),--1896-1940--Tender is the night--Criticism and interpretation, Hemingway, Ernest,--1899-1961--Sun also rises--Criticism and interpretation, Literature and society--United States, Symbolism in literature, Travel in literature, Postmodernism (Literature)
Format
Document (PDF)
Mobile visual search
Title
Mobile visual search.
Creator
Tyagi, Vivek K., Graduate College
Date Issued
2010-04-09
PURL
http://purl.flvc.org/fcla/dt/3176896
Format
Document (PDF)
Mobility management in voice over IP networks
Title
Mobility management in voice over IP networks.
Creator
Sugunan, Shiby., Florida Atlantic University, Ilyas, Mohammad, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description
Wireless Internet access has recently gained significant attention as wireless/mobile communications and networking become widespread. Voice over IP service is likely to play a key role in the convergence of IP based Internet and mobile cellular networks. The mobility management performance for Mobile IP and Session Initiation Protocol is the focus of this thesis. After illustrating the operation of the protocols, the discrete event simulator, Network Simulator 2 (ns2), is used to compare the...
Show moreWireless Internet access has recently gained significant attention as wireless/mobile communications and networking become widespread. Voice over IP service is likely to play a key role in the convergence of IP based Internet and mobile cellular networks. The mobility management performance for Mobile IP and Session Initiation Protocol is the focus of this thesis. After illustrating the operation of the protocols, the discrete event simulator, Network Simulator 2 (ns2), is used to compare the performance of the two protocols. The comparison of the protocols is done by comparing average end-to-end delay and the ratio of the number of packets received to the number of packets originally sent (Packet Delivery Fraction). The impact of mobility is analyzed by studying the performance of the protocols, for various mobility scenarios. The effect of an increase in the number of nodes and increase in velocity of the mobile node on the performance of the Mobile IP and SIP is compared. The performance of the Mobile IP and SIP is compared by measuring the performance metrics of the two protocols for similar simulations. The results obtained as a result of the simulations leads us to some interesting conclusions.
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Date Issued
2004
PURL
http://purl.flvc.org/fcla/dt/13113
Subject Headings
Internet telephony, Wireless Internet, Mobile computing, TCP/IP (Computer network protocol)
Format
Document (PDF)
Mobility pattern-based routing algorithm for mobile ad hoc wireless networks
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.
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Date Issued
2000
PURL
http://purl.flvc.org/fcla/dt/12662
Subject Headings
Mobile computing, Wireless communication systems, Computer algorithms
Format
Document (PDF)
Mobility power flow (MPF) approach applied to fluid-loaded shells with ring discontinuities
Title
Mobility power flow (MPF) approach applied to fluid-loaded shells with ring discontinuities.
Creator
McCain, Thomas Scott., Florida Atlantic University, Cuschieri, Joseph M., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description
The vibrational and acoustic characteristics of fluid-loaded, cylindrical shells with single or multiple, aperiodically-spaced ring discontinuities are studied using an approach based on the mobility power flow (MPF) method and a hybrid numerical/analytical method for the evaluation of the velocity Green's function of the shell. The discontinuities are associated with internal structures coupled to the shell via ring junctions. The approach is a framework allowing alternative shell and/or...
Show moreThe vibrational and acoustic characteristics of fluid-loaded, cylindrical shells with single or multiple, aperiodically-spaced ring discontinuities are studied using an approach based on the mobility power flow (MPF) method and a hybrid numerical/analytical method for the evaluation of the velocity Green's function of the shell. The discontinuities are associated with internal structures coupled to the shell via ring junctions. The approach is a framework allowing alternative shell and/or internal structure models to be used. The solution consists of the net vibrational power flow between the shell and internal structure(s) at the junction(s), the shell's velocity Green's function, and the far-field acoustic pressure. Use of the MPF method is advantageous because the net power flow solution can be used as a diagnostic tool in ascertaining the proper coupling between the shell and internal structure(s) at the junction(s). Results are presented for two canonical problems: an infinite, thin cylindrical shell, externally fluid-loaded by a heavy fluid, coupled internally to: (1) a single damped circular plate bulkhead, and (2) a double bulkhead consisting of two identical damped circular plates spaced a shell diameter apart. Two excitation mechanisms are considered for each model: (1) insonification of the shell by an obliquely-incident, acoustic plane wave, and (2) a radial ring load applied to the shell away from the junction(s). The shell's radial velocity Green's function and far-field acoustic pressure results are presented and analyzed to study the behavior of each model. In addition, a comparison of these results accentuates the qualitative difference in the behavior between the single and multiple junction models. When multiple internal structures are present, the results are strongly influenced by inter-junction coupling communicated through the shell and the fluid. Results are presented for circumferential modes n = 0 & 2. The qualitative differences in the results for modes n = 0 and n = 2 (indicative of all modes n > 0ified in the far-field acoustic pressure and velocity Green's function response with the characteristics of the shell and internal plate bulkhead. The results for the single junction model demonstrate the significance of the shell's membrane waves on the reradiation of acoustic energy from the shell; however, when multiple junctions are present, inter-junction coupling results in a significant broad acoustic scattering pattern. Using the results and analysis presented here, a better understanding can be obtained of fluid-loaded shells, which can be used to reduce the strength of the acoustic pressure field produced by the shell.
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Date Issued
1996
PURL
http://purl.flvc.org/fcla/dt/12490
Subject Headings
Shells (Engineering)--Vibration, Cylinders--Vibration, Fluid dynamics, Sound--Transmission
Format
Document (PDF)
Mobility power flow analysis of an infinite cylindrical shell with an enclosed plate discontinuity
Title
Mobility power flow analysis of an infinite cylindrical shell with an enclosed plate discontinuity.
Creator
Buchmann, Patrick Pierre., Florida Atlantic University, Cuschieri, Joseph M.
Abstract/Description
A mobility power flow approach is used to study the response of an infinitely-long cylindrical shell with an internal plate discontinuity. The shell is excited by either a ring radial force or by a plane acoustic wave. The junction between the shell and the internal plate is assumed to be radially pinned such that in-plane waves of the plate can be neglected. The junction forces are expressed in terms of the mobility functions of the plate and the shell. From knowledge of the junction forces...
Show moreA mobility power flow approach is used to study the response of an infinitely-long cylindrical shell with an internal plate discontinuity. The shell is excited by either a ring radial force or by a plane acoustic wave. The junction between the shell and the internal plate is assumed to be radially pinned such that in-plane waves of the plate can be neglected. The junction forces are expressed in terms of the mobility functions of the plate and the shell. From knowledge of the junction forces and velocities, the power input, the power flow from the shell to the plate, the shell response and the radiated far-field scattered pressure are determined for the circumferential mode n = 0. The results show how the energy propagates from one structure to the other, and present a very clear picture of the characteristics of the scattering pattern from the junction forces.
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Date Issued
1994
PURL
http://purl.flvc.org/fcla/dt/15113
Subject Headings
Shells (Engineering)--Vibration, Plates (Engineering)--Vibration, Structural dynamics, Vibration
Format
Document (PDF)

Pages