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2006

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Compact Modeling Of Silicon Carbide (Sic) Vertical Junction Field Effect Transistor (Vjfet) In Pspice Using Angelov Model And Pspice Simulation Of Analog Circuit Building Blocks Using Sic Vjfet Model, Siddharth Purohit Dec 2006

Compact Modeling Of Silicon Carbide (Sic) Vertical Junction Field Effect Transistor (Vjfet) In Pspice Using Angelov Model And Pspice Simulation Of Analog Circuit Building Blocks Using Sic Vjfet Model, Siddharth Purohit

Theses and Dissertations

This thesis presents the development of compact model of novel silicon carbide (SiC) Vertical Junction Field Effect Transistor (VJFET) for high-power circuit simulation. An empirical Angelov model is developed for SiC VJFET in PSpice. The model is capable of accurately replicating the device behavior for the DC and Transient conditions. The model was validated against measured data obtained from devices developed by Mississippi Center for Advanced Semiconductor Prototyping at MSU and SemiSouth Laboratories. The modeling approach is based on extracting Angelov Equations Coefficients from experimental device characteristics using non linear fitting. The coefficients are extracted for different parameters (temperature, width, …

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Development And Validation Of A Control Strategy For A Parallel Hybrid (Diesel-Electric) Powertrain, Jimmy C. Mathews Dec 2006

Development And Validation Of A Control Strategy For A Parallel Hybrid (Diesel-Electric) Powertrain, Jimmy C. Mathews

Theses and Dissertations

The rise in overall powertrain complexity and the stringent performance requirements of a hybrid electric vehicle (HEV) have elevated the role of its powertrain control strategy to considerable importance. Iterative modeling and simulation form an integral part of the control strategy design process and industry engineers rely on proprietary ?legacy? models to rapidly develop and implement control strategies. However, others must initiate new algorithms and models in order to develop production-capable control systems. This thesis demonstrates the development and validation of a charge-sustaining control algorithm for a through-the-road (TTR) parallel hybrid (diesel-electric) powertrain. Some unique approaches used in powertrain-level control …

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Development Of Power Flow With Distributed Generators And Reconfiguration For Restoration Of Unbalanced Distribution Systems, Sarika Khushalani Dec 2006

Development Of Power Flow With Distributed Generators And Reconfiguration For Restoration Of Unbalanced Distribution Systems, Sarika Khushalani

Theses and Dissertations

With the increasing interest in distribution automation, distribution power flow is important for applications like VAR planning, switching, state estimation and especially optimization. Typically, a distribution system originates at a substation and continues to a lower voltage for delivery to the customers. There are several tools for transmission system analysis. These tools include Newton Raphson, Gauss Seidel and fast decoupled techniques. These techniques however sometimes fail to converge when applied to distribution systems due to their higher resistance/reactance (R/X) ratio of the lines, making them ill conditioned. Distribution systems typically have a radial topological structure where the loads are not …

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Diagonal And Horizontal Stiffeners For Shear Transfer In Rigid Frame Square Knees, William Franklin Heard Dec 2006

Diagonal And Horizontal Stiffeners For Shear Transfer In Rigid Frame Square Knees, William Franklin Heard

Theses and Dissertations

The research addresses the effect of diagonal and horizontal stiffeners on shear transfer in rigid frame square knees. Rigid frame square knees are an integral component of pre-manufactured metal building systems. This paper examined a more efficient design of the rigid frame square knee. Five full-scale laboratory tests on square knee joints were performed to verify the effects of a diagonal stiffener on shear transfer. Two frames were fabricated without diagonal stiffeners, and three frames were fabricated with 1/8- inch- thick diagonal stiffeners, not extending the full diagonal length of the knee web. Experimental results, coupled with a finite element …

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Study Of Lunar Constellations For Situational Awareness And Surveillance, Devon Sanders Dec 2006

Study Of Lunar Constellations For Situational Awareness And Surveillance, Devon Sanders

Theses and Dissertations

Lunar constellations providing the capabilities of situational awareness and surveillance for future mission operators are analyzed in this study. The use of specialty orbits, such as sun-synchronous and frozen orbits, are analyzed to determine the applicability of these unique orbits. Additionally, altitude and inclination trades are performed to determine the degree to which mission objectives are achieved through ranges of these orbital parameters. Using the analyzed orbits, constellations of varying patterns are developed and surface coverage figures of merit are used to evaluate them. The research concludes with calculation of the yearly cross-track and in-track stationkeeping costs of a representative …

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Effective Modeling Of Agricultural Practices Within Large-Scale Hydrologic And Water Quality Simulations, Zhijun Liu Dec 2006

Effective Modeling Of Agricultural Practices Within Large-Scale Hydrologic And Water Quality Simulations, Zhijun Liu

Theses and Dissertations

The previously developed watershed hydrological and water quality model for St. Louis Bay watershed by Kieffer (2002) was refined and calibrated. The aspects of model development refinement included development of fertilization-related nutrient input parameters, evaluation of nutrient input methods, development of plant uptake-related nutrient input parameters, non-cropland simulation using PQUAL module, and recalibration of hydrology in Jourdan River. The related information of typical cropland management practice based on consultation from Mississippi State University Extention Service personnel was integrated into the watershed model. In addition, the Mississippi Department of Environmental Quality (MDEQ) observed water quality data were analyzed to evaluate the …

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Singer-Songwriter Ann Reed To Perform At Blue Moon Coffeehouse, Meg Dubuque Dec 2006

Singer-Songwriter Ann Reed To Perform At Blue Moon Coffeehouse, Meg Dubuque

News and Events (Discontinued Series)

No abstract provided.

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Armstrong Commencement Program, Armstrong Atlantic State University Dec 2006

Armstrong Commencement Program, Armstrong Atlantic State University

Armstrong Commencement Programs

Graduation program for this commencement from Armstrong Atlantic State University in Savannah, Georgia on December 9, 2006. The program includes an order of ceremony and list of graduates.

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Preservice Teachers' Procedural And Conceptual Understanding Of Fractions And The Effects Of Inquiry-Based Learning On This Understanding, Hope Marchionda Dec 2006

Preservice Teachers' Procedural And Conceptual Understanding Of Fractions And The Effects Of Inquiry-Based Learning On This Understanding, Hope Marchionda

All Dissertations

ABSTRACT Non-negative rational numbers play a major role in the K-8 curriculum and continue to permeate mathematics content through high school and college in all strands of mathematics. The difficulty that both students and teachers encounter with these concepts is well documented in the literature. This study looked at preservice teacher knowledge and how an alternative means of instruction might improve their conceptual understanding of fractions. To accomplish this task, the study took place in two stages over the course of two semesters. During the first stage, preservice teachers' conceptual and procedural knowledge of fractions and their associated algorithms were …

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Real-Time Vehicle Performance Monitoring With Data Integrity, William George Jenkins Dec 2006

Real-Time Vehicle Performance Monitoring With Data Integrity, William George Jenkins

Theses and Dissertations

A cornerstone of next generation intelligent transportation systems (ITS) is a seamless integration of in-vehicle networking with existing wireless telephony infrastructure. Remote access to on-board diagnostics and performance data is a crucial requirement for ITS. This thesis investigated the performance benefits of a data integrity buffering technique for an extensible vehicle position and performance tracking system (VPPTS). In support of this investigation, a VPPTS prototype was developed. The prototype used available technologies and interfaces to industry-standard communications channels and is a demonstration of a next-generation intelligent transportation system (ITS). The data integrity buffering technique under investigation was shown to provide …

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Commencement Speech December 2006, Prairie View A&M University Dec 2006

Commencement Speech December 2006, Prairie View A&M University

President Emeritus George C. Wright Speeches

No abstract provided.

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Multi-Agent Based Control And Reconfiguration For Restoration Of Distribution Systems With Distributed Generators, Jignesh M. Solanki Dec 2006

Multi-Agent Based Control And Reconfiguration For Restoration Of Distribution Systems With Distributed Generators, Jignesh M. Solanki

Theses and Dissertations

Restoration entails the development of a plan consisting of opening or closing of switches, which is called reconfiguration. This dissertation proposes the design of a fast and efficient service restoration with a load shedding method for land-based and ship systems, considering priority of customers and several other system operating constraints. Existing methods, based on centralized restoration schemes that require a powerful central computer, may lead to a single point of failure. This research uses a decentralized scheme based on agents. A group of agents created to realize a specific goal by their interactions is called a Multi-Agent System (MAS). Agents …

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Hybrid Electric Vehicle Modeling In Generic Modeling Environment, Shravana Kumar Musunuri Dec 2006

Hybrid Electric Vehicle Modeling In Generic Modeling Environment, Shravana Kumar Musunuri

Theses and Dissertations

The Hybrid Electric Vehicle (HEV) is a complex electromechanical system with complex interactions among various components. Due to the large number of design variables involved, the design flexibility in the HEV makes performance studies difficult. As the system complexity and sophistication increases, it becomes much more difficult to predict these interactions and design the system accordingly. Also, different variations in the design and manufacture of various components and systems involve a large amount of work and cost to keep updated of all these variations. While the above issues ask for a flexible design environment suitable for vehicle design, most of …

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Hyperspectral Dimensionality Reduction Via Sequential Parametric Projection Pursuits For Automated Invasive Species Target Recognition, Terrance Roshad West Dec 2006

Hyperspectral Dimensionality Reduction Via Sequential Parametric Projection Pursuits For Automated Invasive Species Target Recognition, Terrance Roshad West

Theses and Dissertations

This thesis investigates the use of sequential parametric projection pursuits (SPPP) for hyperspectral dimensionality reduction and invasive species target recognition. The SPPP method is implemented in a top-down fashion, where hyperspectral bands are used to form an increasing number of smaller groups, with each group being projected onto a subspace of dimensionality one. Both supervised and unsupervised potential projections are investigated for their use in the SPPP method. Fisher?s linear discriminant analysis (LDA) is used as a potential supervised projection. Average, Gaussian-weighted average, and principal component analysis (PCA) are used as potential unsupervised projections. The Bhattacharyya distance is used as …

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Installation And Instrumentation Of A Micro-Chp Demonstration Facility, Nicholas Alexander Stone Dec 2006

Installation And Instrumentation Of A Micro-Chp Demonstration Facility, Nicholas Alexander Stone

Theses and Dissertations

Micro-Cooling, Heating and Power (CHP) is the decentralized generation of electricity in which normally wasted heat is recovered for use in heating and cooling of the space. A micro-CHP demonstration facility is needed to showcase the system and allow for experiments to be performed. This thesis illustrates the steps taken for the installation and instrumentation of a Micro-CHP (Cooling, Heating, and Power) demonstration facility. Equipment sizing was performed by creating an accurate building model and performing a transient building analysis. Temperature, pressure, flow rate, and relative humidity are measured in order to determine accurate energy balances through each piece of …

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T-6a Texan Ii In-Flight Simulation And Variable Stability System Design, Kenneth Paul Germann Dec 2006

T-6a Texan Ii In-Flight Simulation And Variable Stability System Design, Kenneth Paul Germann

Theses and Dissertations

Inlight variable stability aircraft and inlight simulation are described. The uses of these vehicles and the associated requirements are described. Several forms of control architecture are identified for use in a T-6A inlight simulator. A non-linear model of the T-6A Texan II is developed for use in MATLAB/SIMULINK®. This model is used to design a feedforward responseeedback controller, based on simplified dynamic inversion. This controller is shown to exercise precise control over the T-6A host aircraft dynamics. This architecture is then used to demonstrate simulation of the A-4 and the F-15 by the T-6A. In addition to proving simplified dynamic …

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The Chemical And Mechanical Effects Of Binding Chitosan To Implant Quality Titanium, Holly Joy Martin Dec 2006

The Chemical And Mechanical Effects Of Binding Chitosan To Implant Quality Titanium, Holly Joy Martin

Theses and Dissertations

Biomedical implants are commonly made from commercially pure titanium and other metal alloys, which are chosen for their strength and density. To improve the stability and promote bone cell growth into the implant, efforts to bond coatings to metal have been extensively studied. Many coatings used are considered bioactive, which promote the adhesion and growth of the bone cells surrounding the implant [A.1]. Of these, the most commonly investigated coating is a ceramic called hydroxyapatite, which is brittle, leading to flaking and inadequate bone cell growth [A.2]. Alternate bioactive coatings are being examined, including chitosan, the deacetylated form of chitin. …

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Effects Of Vasoactive Agents On The Mechanical Properties Of Aortic Heart Valve Leaflets, Rebecca Lynn Pounders Mathis Dec 2006

Effects Of Vasoactive Agents On The Mechanical Properties Of Aortic Heart Valve Leaflets, Rebecca Lynn Pounders Mathis

Theses and Dissertations

Heart valve disease is currently one of the leading forms of heart disease. Current literature has shown that endothelin I, angiotension II and 5-HT are vasoactive agents which cause concentration dependent contractions in aortic valve leaflet tissue. This study tested the mechanical properties of leaflets cut in the radial direction after they were exposed to the agents at varied concentrations or for 0.5, 6 or 24 hours. The elastic modulus, ultimate tensile strength and the yield strength were calculated. In the time trials the elastic modulus and the ultimate tensile strength both showed a significant increase at 24-hours. However, there …

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An Energy Efficient Data Cache Implementing 2-Way Lrc Architecture, Saibhushan Musalappa Dec 2006

An Energy Efficient Data Cache Implementing 2-Way Lrc Architecture, Saibhushan Musalappa

Theses and Dissertations

Conventional level one data caches are widely used in high-performance microprocessors. Shrinking process parameters in chip fabrication technology allow a much larger number of devices on a chip with every new generation. This reduction in device size has led to an increase in the magnitude of a type of energy dissipation hitherto ignored?leakage energy. Transistor level leakage energy research for sub-micron processes has shown that leakage can be as much as or greater than the dynamic energy for advanced circuit designs. Researchers have devised techniques to reduce leakage energy at the fabrication and circuit levels. Transitioning the idle circuits from …

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Heat Transfer And Friction In Helically-Finned Tubes Using Artificial Neural Networks, Gregory J. Zdaniuk Dec 2006

Heat Transfer And Friction In Helically-Finned Tubes Using Artificial Neural Networks, Gregory J. Zdaniuk

Theses and Dissertations

The last few decades have seen a significant development of complex heat transfer enhancement geometries such as a helicallyinned tube. The arising problem is that as the fins become more complex, so does the prediction of their performance. In addition to discussing existing prediction tools, this dissertation demonstrates the successful use of artificial neural networks as a correlating method for experimentally- measured heat transfer and friction data of helicallyinned tubes.

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Madrigal Holiday Feast (December 9-10, 2006), Lindenwood University Dec 2006

Madrigal Holiday Feast (December 9-10, 2006), Lindenwood University

Student Theatre Programs

Program for Madrigal Holiday Feast (December 9-10, 2006).

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Design Drawing In Instructional Design At Brigham Young University's Center For Instructional Design: A Case Study, S. Todd Stubbs Dec 2006

Design Drawing In Instructional Design At Brigham Young University's Center For Instructional Design: A Case Study, S. Todd Stubbs

Theses and Dissertations

The purpose of this study is to compare the use of design drawing in design fields such as architecture, engineering, and industrial design with its use in instructional design (ID). This study was conducted in three parts: first, a review of literature to understand the role and value design drawing plays in non-ID fields; second, a search for design drawing in the literature of ID; and third, observations of actual use of design drawing in ID in the field. For the first part, the literature of design studies was reviewed regarding design drawing. For the second part, the literature review …

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Selecting Keyword Search Terms In Computer Forensics Examinations Using Domain Analysis And Modeling, Alfred Christopher Bogen Dec 2006

Selecting Keyword Search Terms In Computer Forensics Examinations Using Domain Analysis And Modeling, Alfred Christopher Bogen

Theses and Dissertations

The motivation for computer forensics research includes the increase in crimes that involve the use of computers, the increasing capacity of digital storage media, a shortage of trained computer forensics technicians, and a lack of computer forensics standard practices. The hypothesis of this dissertation is that domain modeling of the computer forensics case environment can serve as a methodology for selecting keyword search terms and planning forensics examinations. This methodology can increase the quality of forensics examinations without significantly increasing the combined effort of planning and executing keyword searches. The contributions of this dissertation include: ? A computer forensics examination …

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Large Scale Synthesis And Derivatization Of Corannulene: The Smallest Buckybowl, Praveen Bachawala Dec 2006

Large Scale Synthesis And Derivatization Of Corannulene: The Smallest Buckybowl, Praveen Bachawala

Theses and Dissertations

The major part of my thesis work includes large scale production of corannulene, C20H10, a bowl-shaped Polycyclic Aromatic Hydrocarbon. Over the road towards corannulene via tetramethylfluoranthene, we improved several steps of the existing multistep procedure. These improvements include: -Nucleophilic displacement of chloride in 2,7-dimethyl-1-chloromethyl- naphthalene with cyanide gave an excellent yield of 2,7-dimethyl-1-naphthalene- acetonitrile when performed in acetonitrile instead of DMSO or acetone/water. -Oxidation of 3,8-dimethyl-1-acenaphthenone to 3,8-dimethylacenaphthaquinone was successfully achieved with HBr/DMSO instead of selenium dioxide, which usually requires tedious work up. -Overall yield of 3,8-dimethylacenaphth- aquinone was greatly improved in comparison with the previous reports. -Palladium catalyzed large …

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A Single Continuous Function As A Model For Fast Rise Exponential Decay Gamma-Ray Bursts, Daniel B. Logue Dec 2006

A Single Continuous Function As A Model For Fast Rise Exponential Decay Gamma-Ray Bursts, Daniel B. Logue

Theses and Dissertations

A quantitative analysis was performed on a sample of Fast-Rise Exponential-Decay gamma-ray bursts using a continuous fitting function. The data were obtained from the Large Area detector catalogue of the Burst and Transient Source Experiment, which flew from 1991-2000 onboard the Compton Gamma-Ray Observatory. The purpose here is to tabulate from the fits quantities associated with gamma-ray bursts, emphasising peak intensity, duration, and characteristic rates of rising and falling. V/Vmax and duration analyses show that the sample of bursts is representative of the larger population of gamma-ray bursts. A modified asymmetric double sigmoidal was found to fit the background subtracted …

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Body Mass Index And Percent Body Fat As Determined By Bioelectrical Impedance Analysis In Children, 7-9 Years Of Age, Patrick Alan Grady Dec 2006

Body Mass Index And Percent Body Fat As Determined By Bioelectrical Impedance Analysis In Children, 7-9 Years Of Age, Patrick Alan Grady

Theses and Dissertations

The purpose of this study was to examine the prevalence of overweight and report mean Body Mass Index (BMI) and percent body fat (%BF) in Black and non-Black children, 7-9 years of age. The study involved 172 students divided as follows: 56 (32.6%) Black females, 45 (26.2%) Black males, 34 (19.7%) non-Black females, and 37 (21.5%) non-Black males. Percent body fat (%BF) was determined by bioelectrical impedance analysis (BIA). Body mass index was calculated as weight (kg)/height (m)². Black females had a statistically greater BMI (19.3 ± 4.8) and %BF (25.7 ± 10.6) than all other groups. Prevalence of at-riskor-overweight …

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A Study Of The Perceptions Of Mississippi Legislators Regarding The Mission And Goals Of Mississippi Community And Junior Colleges, Samuel Lee Jones Dec 2006

A Study Of The Perceptions Of Mississippi Legislators Regarding The Mission And Goals Of Mississippi Community And Junior Colleges, Samuel Lee Jones

Theses and Dissertations

This study examined the perceptions of the Mississippi legislature that served in the 2006 government session concerning community/junior college mission and goals. There were six research questions in the study pertaining to current and future goal statements. A discrepancy-type survey instrument was developed based on the Community College Goals Inventory developed by the Educational Testing Service and the American Association of Community and Junior Colleges (AACJC). Respondents were asked to rate 40 goal statements in terms of how important the goal statement ?is,? which was current, and how important it ?should be,? which was future. The following goal areas were …

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Monte-Carlo Simulation Of Photoproduction Of Omega Meson, Parikshit Manoj Junnarkar Dec 2006

Monte-Carlo Simulation Of Photoproduction Of Omega Meson, Parikshit Manoj Junnarkar

Theses and Dissertations

The null result of December 2004 Sub-threshold photoproduction of J/$psi$ experiment has motivated this thesis. This monte-carlo predicts the cross-section for sub-threshold photoproduction process and provides an insight on the cross-section range of these processess. The experiment was also conducted as a calibration run for Omega and Eta mesons for the verification of correctness of experimental procedure. The results from this experiment are compared with the monte-carlo simulation for the number of omega meson events. This is primarily done as the models for photoproduction of omega meson are well tested. The monte-carlo provides satisfactory results for the photoproduction models and …

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The Influence Of Instructional Coaches On Improving Teaching And Student Performance, Mariella Hodges Simons Dec 2006

The Influence Of Instructional Coaches On Improving Teaching And Student Performance, Mariella Hodges Simons

Theses and Dissertations

Instructional coaching is emerging as a job-embedded professional development tool for schools to utilize in an effort to improve teaching practice and student achievement. Since there is a lack of understanding of the differing roles served by instructional coaches in schools and the functions they perform that influence teacher utilization of best practice procedures in teaching, this study concentrated on giving voice to teachers and administrators regarding their concerns and changes in teaching behavior. By listening to the assertions of educators employed within the schools housing an instructional coach, it is possible to gain an in-depth understanding of how the …

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Tao Residents' Perceptions Of Social And Cultrual Impacts Of Tourism In Lan-Yu, Taiwan, Cheng-Hsuan Hsu Dec 2006

Tao Residents' Perceptions Of Social And Cultrual Impacts Of Tourism In Lan-Yu, Taiwan, Cheng-Hsuan Hsu

All Theses

The purpose of this study was to investigate residents' perceptions of the social and cultural impacts of tourism on Lan-Yu (Orchid Island). More specifically, this study examines Lan-Yu's aboriginal residents' (The Tao) perceptions of social and cultural impacts of tourism. Systematic sampling was the sampling procedure employed in this study. After the factor analysis, three underlying dimensions were found when examining Tao residents' perceptions of social and cultural impacts of tourism, and they were named: positive cultural effects, negative cultural effects, and negative social effects. The results from the multivariate analysis of variance indicated that the Tao's perceptions toward social …

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