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The Effect Of Integrated Science, Engineering, Technology, And Mathematics Lessons On Interest And Engagement Of Secondary Students, Cameron Nunan Apr 2015

The Effect Of Integrated Science, Engineering, Technology, And Mathematics Lessons On Interest And Engagement Of Secondary Students, Cameron Nunan

Open Access Theses

This study set out to answer the research question: Does teaching a single lesson, utilizing the interconnected principles of STEM in STEM courses, increase overall student interest and engagement in STEM classes in secondary schools? The literature review established a need for student interest in STEM to help fill future STEM careers. ^ Integrated STEM lessons were a viable option for increasing interest, but existing research on the matter was limited. Integrated STEM lessons were applied at a test site school using a multiple baseline framework and evaluated responses with a variation of the Intrinsic Motivation Inventory (IMI). According to …

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The Stability Of The Iris As A Biometric Modality, Benjamin Wright Petry Apr 2015

The Stability Of The Iris As A Biometric Modality, Benjamin Wright Petry

Open Access Theses

In this thesis, the question of the stability of a group of individual subjects' irises is examined and answered. This stability is examined in regards to the time scale of the month range. The covariate for this research was time. Images collected during one month of separation between captures were examined. The genuine and impostor scores for these images were calculated and then interpreted using the stability score index. This index produced a quantifiable value for the stability of iris match scores over the months of the examination. ^ Additionally, a new framework for collecting and analyzing time in biometrics …

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Flexible Weapons Architecture Design, William C. Pyant Apr 2015

Flexible Weapons Architecture Design, William C. Pyant

Open Access Theses

Present day air-delivered weapons are of a closed architecture, with little to no ability to tailor the weapon for the individual engagement. The closed architectures require weaponeers to make the target fit the weapon instead of fitting the individual weapons to a target. The concept of a flexible weapons aims to modularize weapons design using an open architecture shell into which different modules are inserted to achieve the desired target fractional damage while reducing cost and civilian casualties. This thesis shows that the architecture design factors of damage mechanism, fusing, weapons weight, guidance, and propulsion are significant in enhancing weapon …

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A Case Study Of Introductory Programming With Moocs, Miguel Angel Javier Ruiz Apr 2015

A Case Study Of Introductory Programming With Moocs, Miguel Angel Javier Ruiz

Open Access Theses

Computational thinking has become a crucial skill for the 21st Century learners in all disciplines. Research suggests that the best and fastest approach to understand the concepts of computational thinking is through developing programming skills. However, finding effective and affordable learning environments to introduce programming skills to a massive scale of students remains a challenge. Currently, the unprecedented utilization of MOOCs represent an opportunity to achieve this goal. But, existing introductory programming MOOCs have failed to provide instructionally-sound experience for learners. The purpose of this descriptive research is two-fold: (1) Identify the affordances of fifteen MOOC's platforms that are best …

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Assessing Impact Of Exposure To Cyberphysical Systems On Student Interest In Information Technology Careers, Mayari I. Serrano Anazco Apr 2015

Assessing Impact Of Exposure To Cyberphysical Systems On Student Interest In Information Technology Careers, Mayari I. Serrano Anazco

Open Access Theses

The main purpose of this project is to determine if the use of Information Technology (IT) tools, specifically cyberphysical devices, in outreach sessions will promote interest of young individuals in pursuing IT careers. The Diversity office of Purdue's College of Technology offers a number of outreach sessions to a variety of target populations throughout the year. Each department in the college has an opportunity to present a session related to a field of study offered by the department. The research was carried out thru the Spring 2015 semester during the DOiT and Vision outreach programs offered through the college's Diversity …

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Studying The Effect Of Parallelization On The Performance Of Andromeda Search Engine: A Search Engine For Peptides, Jigna Shah Apr 2015

Studying The Effect Of Parallelization On The Performance Of Andromeda Search Engine: A Search Engine For Peptides, Jigna Shah

Open Access Theses

Human body is made of proteins. The analysis of structure and functions of these proteins reveal important information about human body. An important technique used for protein evaluation is Mass Spectrometry. The protein data generated using mass spectrometer is analyzed for the detection of patterns in proteins. A wide variety of operations are performed on the data obtained from a mass spectrometer namely visualization, spectral deconvolution, peak alignment, normalization, pattern recognition and significance testing. There are a number of software that analyze the huge volume of data generated from a mass spectrometer. An example of such a software is MaxQuant …

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How Effective Is Group Feedback In Encouraging Occupants Of An Office Building To Reduce Energy Consumption?, Ushik D. Shah Apr 2015

How Effective Is Group Feedback In Encouraging Occupants Of An Office Building To Reduce Energy Consumption?, Ushik D. Shah

Open Access Theses

Lighting contributes to a high percentage of the total energy use in office buildings. The lack of financial incentive often dissuades office workers from trying to save electricity at their work place. This thesis aims at reducing the total power consumed by an office building by using persuasive technologies on the occupants to promote environmentally conscious and energy saving behavior. ^ A three week field study was conducted by providing occupants of an office building feedback about their energy consumption along with messages to encourage them to save energy. Feedback was provided via television screens and flyers placed strategically at …

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Growth Parameters Of 'Golden Delicious' Apple Trees (Malus X Domestica Borkh), Biying Shi Apr 2015

Growth Parameters Of 'Golden Delicious' Apple Trees (Malus X Domestica Borkh), Biying Shi

Open Access Theses

High yield and high quality of tree fruit result from appropriate orchard design and management practices. This requires an accurate knowledge of vegetative growth, branching, and flowering processes of fruit trees. Tree development knowledge is the fundamental information necessary to build functional-structural tree models, which have various applications in agriculture. To build such models, information is needed on the distributions of growth parameters, not merely means as are often reported. The objective of this study was to quantitatively analyze shoot development and examine the correlations between fruit quality and light distribution in apple trees. This study was conducted in 2014, …

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Numerical Simulation And Characterization Of Jet Flows In Indoor Environments, Zhu Shi Apr 2015

Numerical Simulation And Characterization Of Jet Flows In Indoor Environments, Zhu Shi

Open Access Theses

Jet flows are prevalent in indoor environment and other engineering applications. Typical examples in indoor environment include the flow discharged from personal ventilation systems, and the jet exhaled through breathing or coughing. When there is density (or temperature) difference between the jet and surroundings, jet flow becomes stratified jet. Due to its complication, stratified jet flow is difficult to model, especially in the developing or transitional region of the flow. Studying stratified jet flows is of great significance for understanding the mixing dynamics of jet and ambient environment. This is particularly important for optimizing indoor environment design, or obtaining accurate …

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Failure Analysis Of High Performance Ballistic Fibers, Jennifer S. Spatola Apr 2015

Failure Analysis Of High Performance Ballistic Fibers, Jennifer S. Spatola

Open Access Theses

High performance fibers have a high tensile strength and modulus, good wear resistance, and a low density, making them ideal for applications in ballistic impact resistance, such as body armor. However, the observed ballistic performance of these fibers is much lower than the predicted values. Since the predictions assume only tensile stress failure, it is safe to assume that the stress state is affecting fiber performance. The purpose of this research was to determine if there are failure mode changes in the fiber fracture when transversely loaded by indenters of different shapes. An experimental design mimicking transverse impact was used …

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Dynamics Of Transitions Between Capillary Stable States Under Weightlessness, Praveen Srikanth Apr 2015

Dynamics Of Transitions Between Capillary Stable States Under Weightlessness, Praveen Srikanth

Open Access Theses

The study of two phase systems with one of the phases obstructing the other is of importance in a lot of fields. Liquid droplets in airways and air bubbles in the blood stream both fall under this category of problems. Helium bubbles in hydrazine fuel lines of satellites also have been found to cause frequent thruster shutdown and also seriously affect spacecraft control. Studies have been carried out until now to look at static equilibrium topologies and stability of such two phase systems in straight, bent and laterally compressed capillaries. In this investigation we look at the dynamics of the …

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A Characteristic-Based Visual Analytics Approach To Detect Subtle Attacks From Netflow Records, Weijie Wang Apr 2015

A Characteristic-Based Visual Analytics Approach To Detect Subtle Attacks From Netflow Records, Weijie Wang

Open Access Theses

Security is essentially important for any enterprise networks. Denial of service, port scanning, and data exfiltration are among of the most common network intrusions. It's urgent for network administrators to detect such attacks effectively and efficiently from network traffic. Though there are many intrusion detection systems (IDSs) and approaches, Visual Analytics (VA) provides a human-friendly approach to detect network intrusions with situational awareness functionality. Overview visualization is the first and most important step in a VA approach. However, many VA systems cannot effectively identify subtle attacks from massive traffic data because of the incapability of overview visualizations. In this work, …

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Recursive Tree Traversal Dependence Analysis, Yusheng Weijiang Apr 2015

Recursive Tree Traversal Dependence Analysis, Yusheng Weijiang

Open Access Theses

While there has been much work done on analyzing and transforming regular programs that operate over linear arrays and dense matrices, comparatively little has been done to try to carry these optimizations over to programs that operate over heap-based data structures using pointers. Previous work has shown that point blocking, a technique similar to loop tiling in regular programs, can help increase the temporal locality of repeated tree traversals. Point blocking, however, has only been shown to work on tree traversals where each traversal is fully independent and would allow parallelization, greatly limiting the types of applications that this transformation …

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Linear Matrix Inequality-Based Nonlinear Adaptive Robust Control With Application To Unmanned Aircraft Systems, David William Kun Apr 2015

Linear Matrix Inequality-Based Nonlinear Adaptive Robust Control With Application To Unmanned Aircraft Systems, David William Kun

Open Access Theses

Unmanned aircraft systems (UASs) are gaining popularity in civil and commercial applications as their lightweight on-board computers become more powerful and affordable, their power storage devices improve, and the Federal Aviation Administration addresses the legal and safety concerns of integrating UASs in the national airspace. Consequently, many researchers are pursuing novel methods to control UASs in order to improve their capabilities, dependability, and safety assurance. The nonlinear control approach is a common choice as it offers several benefits for these highly nonlinear aerospace systems (e.g., the quadrotor). First, the controller design is physically intuitive and is derived from well known …

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Loss Of Accuracy Using Smeared Properties In Composite Beam Modeling, Ning Liu Apr 2015

Loss Of Accuracy Using Smeared Properties In Composite Beam Modeling, Ning Liu

Open Access Theses

Advanced composite materials have broad, proven applications in many engineering systems ranging from sports equipment sectors to components on the space shuttle because of their lightweight characteristics and significantly high stiffness. Together with this merit of composite materials is the challenge of improving computational simulation process for composites analysis. Composite structures, particularly composite laminates, usually consist of many layers with different lay-up angles. The anisotropic and heterogeneous features render 3D finite element analysis (FEA) computationally expensive in terms of the computational time and the computing power. ^ At the constituent level, composite materials are heterogeneous. But quite often one homogenizes …

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A Bracketing Method For Proton Affinity Measurements Of Dehydro-And Didehydropyridines, Guannan Li Apr 2015

A Bracketing Method For Proton Affinity Measurements Of Dehydro-And Didehydropyridines, Guannan Li

Open Access Theses

Proton affinity (PA) is a fundamental property that is related to the structure and reactivity of a molecule. Currently, very few experimental PA values are available for organic radicals and none for biradicals. Equilibrium methods cannot be used for these measurements. The traditional bracketing method is based on monitoring reactions of different reference bases with known proton affinities with the protonated analyte for the occurrence of exothermic proton transfer to determine the upper and lower limits of proton affinity. However, the energy deposited into the precursor ions upon CAD when forming protonated radicals may cause endothermic proton transfer reactions occur …

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Real-Time Rss-Based Indoor Navigation For Autonomous Uav Flight, Sangjun Lee Apr 2015

Real-Time Rss-Based Indoor Navigation For Autonomous Uav Flight, Sangjun Lee

Open Access Theses

Navigation for the autonomous flight of Unmanned Aerial Vehicles (UAVs) in an indoor space has attracted much attention recently. One of the main goals of an indoor navigation system is developing an alternative method to obtain position information that can replace or complement the global positioning system. While much research has focused on vision-based indoor navigation systems, this paper aims to develop a Received Signal Strength (RSS)-based navigation system, which is a more cost effective alternative. Then, the position and attitude of a UAV can be computed by the fusion of RSS measurements and measurements from the onboard inertial measurement …

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An Empirical Approach To The Re-Creation Of Vehicle Drive Cycles, Andrew J. Larson Apr 2015

An Empirical Approach To The Re-Creation Of Vehicle Drive Cycles, Andrew J. Larson

Open Access Theses

Vehicles such as buses, delivery trucks, mining equipment, and motorsport vehicles often repeat a highly defined pattern, route, or track during normal use. For these vehicles, standard dynamometer drive cycles are of little use. It was proposed that deriving a vehicle drive cycle from empirical data collected from on-board vehicle sensors would produce more accurate vehicle characteristic predictions for special purpose vehicles. This study answers the question "Is it possible to use recorded vehicle data to replicate a real world driving scenario for the purpose of vehicle diagnostics?" To reduce the complexity of the project, an electric go-kart was used …

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Four Runway Configuration Types And Their Relation To Arrival Delays, Rachel Jayne Kennedy Apr 2015

Four Runway Configuration Types And Their Relation To Arrival Delays, Rachel Jayne Kennedy

Open Access Theses

Aside from a safe flight, airline passengers expect to arrive to their destination on time. With an abundance of flights in the United States arriving late each day, it has yet to be determined if the airport's layout plays a role. This research looks at four common runway configuration types at hub and non-hub airports to determine if runway configurations affect arrival delays. A two-way ANOVA is conducted comparing the means of the on-time arrival percentage between airports exhibiting each of the four runway configurations as well as hub and non-hub airport status. The results determine if any or none …

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Mass Transfer Of Large Molecules Through Collagen And Collagen-Silica Hybrid Membranes, Pedro Jofre Lora Apr 2015

Mass Transfer Of Large Molecules Through Collagen And Collagen-Silica Hybrid Membranes, Pedro Jofre Lora

Open Access Theses

Diabetes is a growing concern in the United States and around the world that must be addressed through new treatment options. Current standard treatment options of diabetes are limiting and have tremendous impacts on patient's lives. Emerging therapies, such as the implantation of encapsulated islets, are promising treatment options, but have not yet materialized due to unsolved problems with material properties. Hybrid silica-collagen membranes address some of these unsolved problems and are a promising material for cell encapsulation. However, the mass transfer properties of large molecules, such as insulin, TNF-α, IL1β, and other important proteins in the etiology of diabetes, …

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Optimal Start-Up Control Of An Evaporation System Modeled As An Interconnected Hybrid Dynamical System, Rithesh Iyer Apr 2015

Optimal Start-Up Control Of An Evaporation System Modeled As An Interconnected Hybrid Dynamical System, Rithesh Iyer

Open Access Theses

The purpose of this research is to investigate the feasibility and advantageous outcomes of modeling a complicated non-linear hybrid dynamical process as an interconnected dynamical system for the purpose of solving a hybrid optimal control problem under the framework of nonlinear model predictive control. This work considers a hybrid model of the startup process of an evaporation system. In this evaporation system a liquid containing mixture of a non-volatile component A and volatile solvents B (water) and C (alcohol) is heated to evaporate the solvents and obtain component A at a higher concentration using a column that is temperature controlled …

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Downward Model Development Of The Soil Moisture Accounting Loss Method In Hec-Hms: Revelations Concerning The Soil Profile, Jessica Holberg Apr 2015

Downward Model Development Of The Soil Moisture Accounting Loss Method In Hec-Hms: Revelations Concerning The Soil Profile, Jessica Holberg

Open Access Theses

Despite the fact that the soil profile is known to impact streamflow, most Curve Number (CN)-based models ignore subsurface processes. This study explores the influence of soil storage on peak flows. Two watersheds in flat, humid west-central Indiana were modeled using both the Natural Resources Conservation Service (NRCS) Curve Number and four versions of the Soil Moisture Accounting (SMA) loss methods in the United States Army Core of Engineers-developed (USACE) Hydrologic Engineering Center Hydrologic Modeling System (HEC-HMS). One watershed encompasses the Wabash and Tippecanoe Rivers' confluence; the other contains an ephemeral stream, Plum Creek. The CN-based model was developed using …

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Uncertainty Quantification And Calibration Of Physical Models, Xian He Apr 2015

Uncertainty Quantification And Calibration Of Physical Models, Xian He

Open Access Dissertations

An ecosystem model is a representation of a real complex ecological system, and is usually described by sophisticated mathematical models. Terrestrial Ecosystem Model (TEM) is one of the ecosystem models, that describes the dynamics of car- bon, nitrogen, water and other vegetation related variables. There are uncertainties in the TEM which are attributed to inaccurate input data, insufficient knowledge of the parameters, inherent randomness and simplification of the physical model. Quantification of uncertainty of such an ecosystem model is computationally very heavy. Bayesian calibration method has been used as an efficient way to calibrate and quantify uncertainties of the computer …

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Development Of Experimental And Instrumental Systems To Study Biological Systems, Amanda J Hemphill Apr 2015

Development Of Experimental And Instrumental Systems To Study Biological Systems, Amanda J Hemphill

Open Access Dissertations

Chapters 1-4 of this thesis describes the development of an experimental system to measure diffusion-limited reaction kinetics in a biological environment. About 100 years ago, the relationship between reaction rate and diffusion in homogenous solution, ie water or buffer, was described as a linear relationship by Smoluchowski. Applying this theory naively would suggest that since the diffusion coefficients drop by factors of 4-100 then the rates of reaction would drop by the same amount. However, recent theory and simulations suggest that this does not hold. Even though biological diffusion coefficients drop to 0.1-20% of that in buffer, these recent studies …

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Discrete Epidemic Models With Arbitrarily Distributed Disease Stages, Nancy Hernandez Ceron Apr 2015

Discrete Epidemic Models With Arbitrarily Distributed Disease Stages, Nancy Hernandez Ceron

Open Access Dissertations

The use of discrete-time models (or discrete models) in the field of mathematical epidemiology has been limited while continuous-time models (or continuous models) are often times preferred, particularly because disease dynamics do occur continuously in time and more mathematical tools are available for model analysis. How- ever, discrete models are not only more tractable and easier to understand, but also more directly related to data, particularly when the disease stage distributions are arbitrarily distributed (e.g., when the data cannot be fitted by distributions from a parametric family). Under these circumstances continuous models usually lead to complex system of integral equations. …

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The Effects Of A Model-Eliciting Activity On High School Student Design Performance, Tanner J Huffman Apr 2015

The Effects Of A Model-Eliciting Activity On High School Student Design Performance, Tanner J Huffman

Open Access Dissertations

Modeling allows students to become more effective designers. High school technology and engineering students engage in engineering design challenges as part of traditional instructional practices. Model-eliciting activities (MEA) present students with opportunities to elicit mathematically thinking that facilitates modeling. Students (n=266) from four schools completed a model-eliciting activity (MEA) and design challenge procedure. The research design utilized a quasi-experimental method, post-test only, with homogenous matching comparison groups based on possible confounding variables. A rubric was used to measure student design performance. Students in the comparison group (n=124) completed a traditional design challenge and were assessed on their design performance. Students …

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Transport Studies In Graphene-Based Materials And Structures, Jiuning Hu Apr 2015

Transport Studies In Graphene-Based Materials And Structures, Jiuning Hu

Open Access Dissertations

Graphene, a single atomic layer of graphite, has emerged as one of the most attractive materials in recent years for its many unique and excellent properties, inviting a broad area of fundamental studies and applications. In this thesis, we present some theoretical/experimental studies about the thermal, electronic and thermoelectric transport properties in graphene-based systems. We employ the molecular dynamic simulations to study the thermal transport in graphene nanoribbons (GNRs) exhibiting various properties, including chirality dependent thermal conductivity, thermal rectification in asymmetric GNRs, defects and isotopic engineering of the thermal conductivity and negative differential thermal conductance (NDTC) at large temperature biases. …

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Design Of Transfers From Earth-Moon L 1/L2 Libration Point Orbits To A Destination Object, Masaki Kakoi Apr 2015

Design Of Transfers From Earth-Moon L 1/L2 Libration Point Orbits To A Destination Object, Masaki Kakoi

Open Access Dissertations

Within the context of both manned and robotic spaceflight activities, orbits near the Earth-Moon L1 and L2 libration points could support lunar surface operations and serve as staging areas for future missions to near-Earth asteroids as well as Mars. In fact, an Earth-Moon L2 libration point orbit has been proposed as a potential hub for excursions to Mars as well as activities in support of planetary exploration. Yet, the dynamical environment within the Earth-Moon system is complex and, consequently, trajectory design in the vicinity of Earth-Moon L1 and L2 is nontrivial. Routine transfers between an Earth-Moon L1/L2 facility and Mars …

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Molecular Diagnosis Of Cancer Using Ambient Ionization Mass Spectrometry, Kevin S Kerian Apr 2015

Molecular Diagnosis Of Cancer Using Ambient Ionization Mass Spectrometry, Kevin S Kerian

Open Access Dissertations

My dissertation focuses on advancing the development and application of ambient ionization mass spectrometry methodology and technology to the biomedical field. The primary ambient ionization method used in my studies is desorption electrospray ionization mass spectrometry (DESI-MS) imaging, which has been previously used to analyze and differentiate disease state (i.e. tumor and normal) and in some cases tumor subtype of human liver, kidney, bladder, testicular, prostate, and brain cancers. DESI-MS imaging is an ideal method for disease diagnosis, because it can be used to directly correlate disease state with histopathology to develop and validate MS libraries built using the molecular …

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Functional Inequalities And The Curvature Dimension Inequality On Totally Geodesic Foliations, Bumsik Kim Apr 2015

Functional Inequalities And The Curvature Dimension Inequality On Totally Geodesic Foliations, Bumsik Kim

Open Access Dissertations

We discover following analytic / geometric properties on Riemannian foliations with bundle-like metric and totally geodesic leaves, or shortly, totally geodesic foliations. Under a certain curvature condition, we obtain (1) Sobolev-isoperimetric inequalities, global Poincar\'e inqualities, and a lower bound for Cheeger's isoperimetric constant, (2) Poincar\'e inequalities on balls and uniqueness of positive(or $L^p,p\geq 1$) solutions for the subelliptic heat equation, (3) A lower bound for the first non-zero eigenvalue of sub-Laplacians (Lichnerowicz theorem), and Obata's sphere theorem. In this context, the curvature condition is a sub-Riemannian analogue of lower bounds for Ricci curvature tensor. Earlier, it is given by Baudoin-Garofalo's …

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