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Structural And Surface Property Characterization Of Titanium Dioxide Nanotubes For Orthopedic Implants, Tolou Shokuhfar

Dissertations, Master's Theses and Master's Reports - Open

This research focused on the to modification of the surface structure of titanium implants with nanostructured morphology of TiO₂ nanotubes and studied the interaction of nanotubes with osteoblast cells to understand the parameters that affect the cell growth. The electrical, mechanical, and structural properties of TiO₂ nanotubes were characterized to establish a better understanding on the properties of such nanoscale morphological structures.

To achieve the objectives of this research work I transformed the titanium and its alloys, either in bulk sheet form, bulk machined form, or thin film deposited on another substrate into a surface of titania nanotubes …

Multispace & Multistructure. Neutrosophic Transdisciplinarity (100 Collected Papers Of Sciences), Vol. Iv, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

The fourth volume, in my book series of “Collected Papers”, includes 100 published and unpublished articles, notes, (preliminary) drafts containing just ideas to be further investigated, scientific souvenirs, scientific blogs, project proposals, small experiments, solved and unsolved problems and conjectures, updated or alternative versions of previous papers, short or long humanistic essays, letters to the editors - all collected in the previous three decades (1980-2010) – but most of them are from the last decade (2000-2010), some of them being lost and found, yet others are extended, diversified, improved versions. This is an eclectic tome of 800 pages with papers …

Use Of Web-Based Lessons Of Statistical Concepts With Graphics And Animation To Enhance The Effectiveness Of Learning, Lavanya Pillala

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Statistics is of critical importance to engineers. However, many engineering students struggle to grasp the meaning of statistical concepts and the idiosyncrasies of statistical methodologies. Because of this problem, instructors of statistics are constantly searching for better ways to help students understand statistical concepts. The goal of this project is to design and develop web-based lessons that use graphics and animations to enhance the effectiveness of students' learning of statistical concepts.

Lessons of three important statistical concepts have been developed for this thesis - normal distribution, central limit theorem and confidence & tolerance intervals - following well-recognized instructional design development …

Effects Of The Antimicrobial Tylosin On The Microbial Community Structure Of An Anaerobic Sequencing Batch Reactor, Toshio Shimada, Xu Li, Julie L. Zilles, Eberhard Morgenroth, Lutgarde Raskin

Department of Civil and Environmental Engineering: Faculty Publications

The effects of the antimicrobial tylosin on a methanogenic microbial community were studied in a glucosefed laboratory-scale anaerobic sequencing batch reactor (ASBR) exposed to stepwise increases of tylosin (0, 1.67, and 167 mg/L). The microbial community structure was determined using quantitative fluorescence in situ hybridization (FISH) and phylogenetic analyses of bacterial 16S ribosomal RNA (rRNA) gene clone libraries of biomass samples. During the periods without tylosin addition and with an influent tylosin concentration of 1.67 mg/L, 16S rRNA gene sequences related to Syntrophobacter were detected and the relative abundance of Methanosaeta species was high. During the highest tylosin dose of …

The Influence Of Hydrogen Peroxide On The Static And Fatigue Properties Of Palacos-R Bone Cement, John M. Guerin

Theses

Aseptic loosening is a very costly complication of joint arthroplasty, both in terms of patient quality of life and financially. One potential contributing factor in its development - namely the use of hydrogen peroxide as an effervescent haemostatic agent - was investigated in this study. Clean bone cement samples and samples contaminated with 6% hydrogen peroxide were manufactured and stored either in room air or normal saline prior to testing. Thus four sample types were tested (clean stored wet or dry and contaminated stored wet or dry). Static (tension to failure) and fatigue testing was performed. Analysis was carried out …

Energy Reduction In Automotive Paint Shops A Review Of Hybrid/Electric Vehicle Battery Manufacturing, Claudia Patricia Arenas Guerrero

University of Kentucky Master's Theses

Automotive industry is facing fundamental challenges due to the rapid depletion of fossil fuels, energy saving and environmental concerns. The need of sustainable energy development has motivated the research of energy reduction and renewable energy sources. Efficient use of energy in vehicle manufacturing is demanded, as well as an alternative energy source to replace gasoline powered engines. In this thesis, we introduce a case study at an automotive paint shop, where the largest amount of energy consumption of an automotive assembly plant takes place. Additionally, we present a summary of recent advances in the area of hybrid and electrical vehicles …

Population Fit Threshold: Fully Automated Signal Map Generation For Baseline Correction In Nmr-Based Metabolomics, Daniel C. Homer

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Baseline correction of NMR-based metabolomic spectra is a key step in data processing to elucidate biomarkers of diseased and toxic states. Automated baseline correction methods often use human-selected parameters. Presented is a method for automated baseline correction using parameters selected from and without manipulation of the spectrum. The focus is on generating an accurate signal map based on the differentiating characteristics of baseline noise and signal. The presented method of signal map generation and baseline correction was developed and tested on 13C and 1H NMR spectra. The spectra were as simple as chemical standards containing less than 25 signal peaks …

Induction Of P53 Dependent Cellular Senescence Through Hdmx Inhibition Or Ypel3 Expression, Kelly Lynn Robbins Miller

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Mutations in p53 that compromise its function have been reported in approximately half of all human cancers (Vousden et al., 2002). The other half of human tumors that retain wild-type p53 have a dysfunctional p53 pathway through other mechanisms (Wade et al., 2009). Activation of p53 leads to cell cycle arrest, DNA repair, apoptosis and senescence, however, the pathway leading to cellular senescence is the focus of this study. Cellular senescence is a process leading to irreversible arrest of cell division. Under normal physiologic conditions, the activity of p53 is kept in check by its negative regulators, Mdm2 and MdmX. …

Patterns Of Dipeptide Usage For Gene Prediction, Dayananda Sagar Gangadharaiah

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As the number of complete genomes that have been sequenced continues to grow rapidly, the identification of genes regions in DNA sequence data remains one of the most important open problems in bio-informatics. Improving the accuracy of such gene finding tools by a small percentage would affect accurate predictions of many genes of an organism (Zhu et al., 2010). This thesis presents a novel approach for identifying coding regions of a genome based on dipeptide usage.

The patterns in dipeptide usage are used to discriminate between coding and non-coding DNA regions. Two sample T-tests are used as tests of significance …

Charaterization Of Chlorpyrifos Toxicity On The Pancreatic Beta Cell Line Rinm5f, Zhongyu Yan

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Chlorpyrifos (CPF) is a well-known organophosphate (OP) insecticide that inhibits acetylcholinesterase (AChE). Organophosphates have been shown to induce hyperglycemia in both humans and animals that cannot be explained by AChE inhibition alone. Pancreatic β-cells are responsible for secreting insulin and playing a fundamental role in glucose homeostasis. The aim of this research was to investigate CPF toxicity on the insulin secreting β-cell line RINm5f (RIN). In the first part of this dissertation, we determined that cytotoxic concentrations of CPF between 50 µM and 200 µM induced a dose-dependent increase in RIN cell apoptotic and necrotic death (p<0.05). Lower doses, i.e., 5-25 µM did not induce apoptosis or necrosis. In further mechanistic studies, inhibitors of c-Jun N-terminal kinase (JNK) and P38 pathways, i.e., SP600125 and SB202190, successfully attenuated CPF-induced apoptosis (p<0.05), suggesting cell death is mediated by JNK and/or p38. In addition, N-Acetyl-L-cysteine (NAC), an antioxidant, inhibited apoptosis suggesting that oxidative stress is also involved in RIN cell death. In the second part of this dissertation, low dose CPF's effects on insulin synthesis and secretion was studied. Our results showed that RIN cells treated with CPF for 4 hr exhibited a dose-dependent decrease in insulin secretion in response to stimulation by 50 mM potassium (p<0.05). Insulin secretion stimulated by 25 mM glucose also showed significant decreases upon incubation with various doses of CPF (p<0.05). Insulin synthesis involves proteolytic cleavage of proinsulin at two specific sites. The enzymes responsible for promoting proinsulin cleavage, i.e, prohormone convertase (PC) 1/3 and 2 (PC2), contain a serine hydrolase catalytic triad, His-Asp-Ser, similar to AChE. CPF modification of PC enzymes similar to AChE, could potentially interrupt the conversion of proinsulin to insulin and disrupt insulin secretion. PC2 enzyme activity was significantly inhibited by CPF at concentrations as low as 10 µM (p<0.01). RIN cells, for the first time, were found to secrete proinsulin was through a constitutive instead of a regulated pathway. In summary, our results show that CPF not only exerts a direct cytotoxic effect at concentrations above 50 µM, but also significantly impairs insulin secretion at lower doses. Low dose CPF could potentially affect endocrine function in vivo by inhibiting the proinsulin processing enzyme PC2.

Aircraft Gearbox Dynamics Subject To Electromechanical Actuator Regenerative Energy Flow, Matthew S. Rutledge

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To increase reliability and efficiency, standard aircraft components are being replaced with more electric subsystems aimed to reduce weight, conserve space, and improve energy management. One application of this process replaces standard hydraulic actuators used in flap or aileron movements with electromechanical actuators powered by an external generator. During different types of return movements, the electromechanical actuator will produce regenerative power that flows back through the generator and pulses into the engine-gearbox subsystem. The regenerative power, defined by characteristic amplitude, frequency, and other pulse attributes, coupled with the driving force produced by the engine may dramatically impact the performance and …

The History, Philosophy, And Practice Of Agent-Based Modeling And The Development Of The Conceptual Model For Simulation Diagram, Brian L. Heath

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This research advances ABM as a generic analysis tool such that ABM can reach its full potential as a revolution in modeling and simulation. To achieve this goal, the field of ABM is examined from many perspectives. The first perspectives examined are complex systems, the historical emergence of ABM, and philosophical issues related to ABM. These topics establish some clear foundations for the field across multiple disciplines. Next the current practice of ABM is investigated. Through a comprehensive 279 article survey some current deficiencies and opportunities in ABM are identified. Based on these opportunities, a new diagramming technique called the …

Design And Development Of A Wireless Data Acquisition System For Fall Detection, Anoop Hanchinamane Ramakrishna

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With the mortality rate of the elderly on the rise due to fall related incidents, fall detection has become an important entity in the geriatric health care sector. The study conducted in this thesis involved the design and development of a Wireless Data Acquisition System (WDAS) with Bluetooth capabilities interfaced to pulse width modulated gyroscopic sensors. Each sensor used has a reference output pulse width which changes when rotated about its sensitive axis.Part of the effort involves the design and development of two versions of printed circuit boards for the application. Each board includes a Parallax Propeller micro- controller in …

Algorithmic Techniques Employed In The Quantification And Characterization Of Nuclear Magnetic Resonance Spectroscopic Data, Paul Edward Anderson

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Nuclear magnetic resonance (NMR) based metabolomics is a developing research field with broad applicability, including the identification of biomarkers associated with pathophysiologic changes, sample classification based on the mechanism of toxicity, and clinical diagnosis. Intrinsic to these applications is the need for statistical and computational techniques to facilitate the associated data analysis. Further, a typical 1H NMR spectrum of pure proteins, biofluids, or tissue may contain thousands of resonances (i.e., peaks), thus, a pure visual inspection is insufficient to fully utilize the spectral information.

Common practice within the NMR-based metabolomics community is to evaluate and validate novel algorithms on empirical …

Visualization Of Complex Unsteady 3d Flow: Flowing Seed Points And Dynamically Evolving Seed Curves With Applications To Vortex Visualization In Cfd Simulations Of Ultra Low Reynolds Number Insect Flight, Christopher M. Koehler

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Three dimensional integration-based geometric visualization is a very powerful tool for analyzing flow phenomena in time dependent vector fields. Streamlines in particular have many perceptual benefits due to their ability to provide a snapshot of the vectors near key features of complex 3D flows at any instant in time. However, streamlines do not lend themselves well to animation. Subtle changes in the vector field at each time step lead to increasingly large changes between streamlines with the same seed point the longer they are integrated. Path lines, which show particle trajectories over time suffer from similar problems when attempting to …

Multiwall Carbon Nanotubes Alter The Thermal Profile And Antibiotic Elution Of Orthopaedic Bone Cement, Alison Carroll Tickle

University of Kentucky Master's Theses

Multiwall carbon nanotubes (MWNTs) have extraordinary mechanical and thermal transport properties. They significantly improve the static and dynamic mechanical properties of acrylic orthopaedic bone cement when added to the dry cement polymer powder. Understanding the role MWNTs play on bone cement polymerization temperatures will lead to improved mechanical integrity of the cement-bone interface in joint arthroplasties. It was determined through thermal testing that MWNTs increased the polymerization time of the methylmethacrylate by 45-460% and decreased the peak exothermic temperature of bone cement with and without antibiotics. The flow of heat produced during polymerizing cement was reduced 25-85% with the addition …

Tob1 Is A Constitutively Expressed Repressor Of Liver Regeneration, Karen J. Ho, Nhue L. Do, Hasan H. Otu, Martin J. Dib, Xianghui Ren, Keiichi Enjyoji, Simon C. Robson, Ernest F. Terwilliger, Seth J. Karp

Department of Electrical and Computer Engineering: Faculty Publications

How proliferative and inhibitory signals integrate to control liver regeneration remains poorly understood. A screen for antiproliferative factors repressed after liver injury identified transducer of ErbB2.1 (Tob1), a member of the PC3/BTG1 family of mito-inhibitory molecules as a target for further evaluation. Tob1 protein decreases after 2/3 hepatectomy in mice secondary to posttranscriptional mechanisms. Deletion of Tob1 increases hepatocyte proliferation and accelerates restoration of liver mass after hepatectomy. Down-regulation of Tob1 is required for normal liver regeneration, and Tob1 controls hepatocyte proliferation in a dose-dependent fashion. Tob1 associates directly with both Caf1 and cyclindependent kinase (Cdk) 1 and …

Draft Programmatic Environmental Impact Statement For The Mechanical Creation And Maintenance Of Emergent Sandbar Habitat In The Riverine Segments Of The Upper Missouri River, Vol. 1 And 2

United States Army Corps of Engineers, Omaha District

This Draft Programmatic Environmental Impact Statement (PEIS) analyzes the potential environmental consequences of implementing the Emergent Sandbar Habitat (ESH) program on the Upper Missouri River. The purpose of the ESH program is to support least tern and piping plover populations on the Missouri River by supplementing natural habitat through the mechanical creation and replacement of ESH. The PEIS allows the public, cooperating agencies (the U.S. Fish and Wildlife Service (USFWS) and the National Park Service (NPS)), and Corps decision makers to compare impacts among a range of alternatives. The PEIS is meant to inform the selection of a preferred alternative …

161. The Potential Role Of Extensor Muscle Fatigue In The Onset Of Intervertebral Disc Degeneration: A Novel In Vivo Model, Mary Beth M. Grabowsky, Nicholas A. Pallota, Matthew W. Connelly, Brett Van Etten, Rebecca A. Wachs, Max Alley, Joseph C. Glennon, Andrew H. Dubin, John W. German, Richard L. Uhl, Eric H. Ledet

Department of Agricultural and Biological Systems Engineering: Faculty Publications

BACKGROUND CONTEXT: Occupation is strongly correlated to low back pain (LBP). Specific occupational activities associated with low back pain include poor posture, whole body vibration, and repetitive lifting. These activities have a common link: they result in fatigue of the primary spinal extensor musculature. This fatigue may lead to increased intervertebral loading - a stimulus for disc degeneration. If true, this association could provide a vital connection between detrimental physical activities and LBP. However, the link between muscle fatigue and increased load across the disc space has never been quantified in vivo.

PURPOSE: The purpose of this study was to …

Transgenic Rat Model Of Neurodegeneration Caused By Mutation In The Tdp Gene, Hongxia Zhou, Cao Huang, Han Chen, Dian Wang, Carlisle P. Landel, Pedro Yuxing Xia, Robert Bowser, Yong-Jian Liu, Xu Gang Xia

Nebraska Center for Biotechnology: Faculty and Staff Publications

TDP-43 proteinopathies have been observed in a wide range of neurodegenerative diseases. Mutations in the gene encoding TDP-43 (i.e., TDP) have been identified in amyotrophic lateral sclerosis (ALS) and in frontotemporal lobe degeneration associated with motor neuron disease. To study the consequences of TDP mutation in an intact system, we created transgenic rats expressing normal human TDP or a mutant form of human TDP with a M337V substitution. Overexpression of mutant, but not normal, TDP caused widespread neurodegeneration that predominantly affected the motor system. TDP mutation reproduced ALS phenotypes in transgenic rats, as seen by progressive degeneration of motor neurons …

Cytocompatible Cross-Linking Of Electrospun Zein Fibers For The Development Of Water-Stable Tissue Engineering Scaffolds, Quiran Jiang, Narendra Reddy, Yiqi Yang

Department of Agricultural and Biological Systems Engineering: Faculty Publications

This paper reports a new method of cross-linking electrospun zein fibers using citric acid as a non-toxic cross-linker to enhance the water stability and cytocompatibility of zein fibers for tissue engineering and other medical applications. The electrospun structure has many advantages over other types of structures and protein-based biomaterials possess unique properties preferred for tissue engineering and other medical applications. However, ultrafine fiber matrices developed from proteins have poor mechanical properties and morphological stability in the aqueous environments required for medical applications. Efforts have been made to improve the water stability of electrospun protein scaffolds using cross-linking and other approaches, …

Microwave-Based Alkali Pretreatment Of Switchgrass And Coastal Bermudagrass For Bioethanol Production, Deepak R. Keshwani, Jay J. Cheng

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Switchgrass and coastal bermudagrass are promising lignocellulosic feedstocks for bioethanol production. However, pretreatment of lignocelluloses is required to improve production of fermentable sugars from enzymatic hydrolysis. Microwave-based alkali pretreatment of switchgrass and coastal bermudagrass was investigated in this study. Pretreatments were carried out by immersing the biomass in dilute alkali reagents and exposing the slurry to microwave radiation at 250 W for residence times ranging from 5 to 20 minutes. Simons’ stain method was used to quantify changes in biomass porosity as a result of the pretreatment. Pretreatments were evaluated based on yields of total reducing sugars, glucose, and xylose. …

Robust Dynamic Balance Of Ap-1 Transcription Factors In A Neuronal Gene Regulatory Network., Gregory M Miller, Babatunde A Ogunnaike, James S Schwaber, Rajanikanth Vadigepalli

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

BACKGROUND: The octapeptide Angiotensin II is a key hormone that acts via its receptor AT1R in the brainstem to modulate the blood pressure control circuits and thus plays a central role in the cardiac and respiratory homeostasis. This modulation occurs via activation of a complex network of signaling proteins and transcription factors, leading to changes in levels of key genes and proteins. AT1R initiated activity in the nucleus tractus solitarius (NTS), which regulates blood pressure, has been the subject of extensive molecular analysis. But the adaptive network interactions in the NTS response to AT1R, plausibly related to the development of …

Nrel: A Year In Clean Energy Innovations: A Review Of Nrel's Feature Stories, National Renewable Energy Laboratory

Publications (E)

The National Renewable Energy Laboratory (NREL) is the nation’s primary laboratory for renewable energy and energy efficiency research and development.

NREL’s mission and strategy are focused on advancing the U.S. Department of Energy’s and our nation’s energy goals. The laboratory’s scientists and researchers support critical market objectives to accelerate research from scientific innovations to market-viable alternative energy solutions. At the core of this strategic direction are NREL’s research and technology development competencies. These areas span from understanding renewable resources for energy, to the conversion of these resources to renewable electricity and fuels, and ultimately to the use of renewable electricity …

Implementing Rfid To Improve Animal Shelter Inventory And Allocation, Adam Mach

Industrial and Manufacturing Engineering

The purpose of this project is to observe the best way to incorporate Radio Frequency Identification (RFID) technology into the animal inventory system present in animal shelters, while also observing the benefits of implementing this system. The Woods Humane Society was used in this project as a sample animal care facility that could benefit from this application.

Many RFID systems can be observed in other industries, but very few examples this technology exist in animal shelters or smaller animal care facilities. Part of the reason for that is because funds are scarce at most animal care facilities, like the Woods …

A Novel Approach To Dual Excitation Ratiometric Optical Mapping Of Cardiac Action Potentials With Di-4-Anepps Using Pulsed Led Excitation, Andrew Dennison Bachtel

All ETDs from UAB

We developed a new method for ratiometric optical mapping of transmembrane potential (Vm) in cardiac preparations stained with di-4-ANEPPS (DI-4). The method uses pulsed light emitting diode (LED) excitation. Vm-dependent shifts of excitation and emission spectra establish two excitation bands (<481 nm and >481 nm) that produce positive and negative changes in fluorescence within a single emission band (570-615 nm). The ratio of these positive and negative fluorescence signals (excitation ratiometry) increases Vm sensitivity and removes artifacts common to both signals. We pulsed blue (460±20 nm) and cyan (505±20 nm) LEDs at 500 Hz in alternating phase synchronized to a photodetector (1 …

Water Resources, Health, And The Sustainability Of Interventions To Achieve Water And Sanitation Targets Of The Millennium Development Goals In A Changing World, Lauren M. Fry

Dissertations, Master's Theses and Master's Reports - Open

This dissertation addresses sustainability of rapid provision of safe water and sanitation required to meet the Millennium Development Goals. Review of health-related literature and global statistics demonstrates engineers' role in achieving the MDGs. This review is followed by analyses relating to social, environmental, and health aspects of meeting MDG targets.

Analysis of national indicators showed that inadequate investment, poor or nonexistent policies and governance are challenges to global sanitation coverage in addition to lack of financial resources and gender disparity. Although water availability was not found to be a challenge globally, geospatial analysis demonstrated that water availability is a potentially …

Influence Of Traumatic Impaction And Pathological Loading On Knee Menisci, Megan Leigh Killian

Dissertations, Master's Theses and Master's Reports - Open

Nearly half of the US population faces the risk of developing knee osteoarthritis (OA). Both in vitro and in vivo studies can aid in a better understanding of the etiology, progression, and advancement of this debilitating disorder. The knee menisci are fibrocartilagenous structures that aid in the distribution of load, attenuation of shock, alignment and lubrication of the knee. Little is known about the biochemical and morphological changes associated with knee menisci following altered loading and traumatic impaction, and investigations are needed to further elucidate how degradation of this soft tissue advances over time. The biochemical response of porcine meniscal …

Integration Of Remote Lidar And In-Situ Measured Data To Estimate Particulate Flux And Emission From Tillage Operations, Vladmir V. Zavyalov, Gail E. Bingham, Michael D. Wojcik, Jerry L. Hatfield, Thomas D. Wilkerson, Randy S. Martin, Christian Marchant, Kori D. Moore, Bill Bradford

Civil and Environmental Engineering Faculty Publications

Agriculture, through wind erosion, tillage and harvest operations, burning, diesel-powered machinery and animal production operations, is a source of particulate matter emissions. Agricultural sources vary both temporally and spatially due to daily and seasonal activities and inhomogeneous area sources. Conventional point sampling methods originally designed for regional, well mixed aerosols are challenged by the disrupted wind flow and by the small mobile source of the emission encountered in this study. Atmospheric lidar (LIght Detection And Ranging) technology provides a means to derive quantitative information of particulate spatial and temporal distribution. In situ point measurements of particulate physical and chemical properties …

An Rfid Based Indoor Tracking Method For Navigating Visually Impaired People, Ruşen Öktem, Eli̇f Aydin

Turkish Journal of Electrical Engineering and Computer Sciences

This paper tackles the RFID based tracking problem in an obscured indoor environment. The proposed solution is an integral part of a navigation aid for guiding visually impaired people in a store. It uses RF signal strengths and is based on the Bayes Decision Theory. An observation vector is formed by received radio signal strength indication values, transmitted from three transmitters at distinct frequencies in the UHF band. The indoor area is divided into square grids, where each grid is considered as a class. The problem of tracking is expressed as classifying the observed radio signal strengths to the most …