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2017

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Bayesian Filtering Estimation Of Statistical Dynamic Factor Model, Yu Mu Dec 2017

Bayesian Filtering Estimation Of Statistical Dynamic Factor Model, Yu Mu

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

Statistical factor analysis has been widely used in many areas of investment science such as risk management, portfolio selection, trading strategies, ect.. This dissertation mainly investigates the estimation of dynamic factor model in the Bayesian framework, using the techniques of particle filter with online parameter learning such as marginalized particle filter and particle learning. We also compare our results with the offline conventional method such as Kalman filter combined with EM algorithm in root mean squared error criterion. In the real data analysis, regime switching or structure break in the factor structure will make the estimation of static model difficult …

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Computational Conformal Geometry And Its Applications, Ming Ma Dec 2017

Computational Conformal Geometry And Its Applications, Ming Ma

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

With the development of 3D acquisition technologies and computational power, conformal geometry plays increasingly important role in engineering fields. Conformal geometry has deep roots in pure mathematics, combining complex analysis, Riemann surface theory, differential geometry, and algebraic topology. In recent years, theory of discrete conformal geometry has been developed. They have been extensively applied in many practical fields. Surface remeshing plays a significant role in computer graphics and visualization. Numerous surface remeshing methods have been developed to produce high quality meshes. Generally, the mesh quality is improved in terms of vertex sampling, regularity, triangle size and triangle shape. Many of …

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Studies In Experimental Population Genetics Of Drosophila Melanogaster, Spencer Arran Koury Dec 2017

Studies In Experimental Population Genetics Of Drosophila Melanogaster, Spencer Arran Koury

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

Population genetics is a model based science with three complementary approaches: theoretical, empirical, and experimental. The last of these employs complex experimental designs to directly estimate model parameters or, when possible, tests causal hypotheses through direct manipulation. Building on the long tradition of experimental population genetics in Drosophila species I propose new mechanisms in evolution of chromosomal rearrangements (Chapters 1-3) and then describe a series of experiments directly testing the role of metabolic genes in temperate adaptation of Drosophila melanogaster (Chapters 4-6). In phylogenetic series of gene arrangements, younger chromosomal inversions tend to be distal to older inversions. After Chapter …

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A New Scaling Law For K62 With Applications To Particle Clustering In Turbulent Flow, Vinay Preston Mahadeo Dec 2017

A New Scaling Law For K62 With Applications To Particle Clustering In Turbulent Flow, Vinay Preston Mahadeo

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

There are two main results in this thesis. We develop a new scaling lawfor the turbulent dissipation rate, ϵ, providing a quantitative extension tothe K62 lognormal postulate. We illustrate this scaling law through its application to subgrid scale (SGS) modeling in the large-eddy simulation (LES) of particle-laden turbulent flows. The second major contribution of this thesis examines the entire covariance matrix of χ = lnϵ inwavenumber space and shows that it is approximately diagonal. Prior turbulence studies of Kolmogorov and Obukhov have explored models for ϵ using lognormal random processes. We extend these ideas and establish a random field theory …

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Discovering New Materials Through First-Principles Evolutionary Algorithms, Jin Zhang Dec 2017

Discovering New Materials Through First-Principles Evolutionary Algorithms, Jin Zhang

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

Materials exhibit new physical and chemical properties under pressure. Discovering the new high-pressure structures, especially those which can be preserved as metastable structures at ambient pressure, are very instructive for practical applications. Compared with high-pressure experiments, theoretically investigating materials' behavior under high pressure is more efficient and less expensive. One motivation of this thesis is to discover new structures under high pressure using USPEX method and to evaluate the stabilities of high-pressure phases at ambient pressure. Another motivation is to calculate and analyze the electronic and mechanical properties of the new high-pressure structures at ambient pressure. With these motivations, we …

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Novel Superconducting Phases Of Materials Under Pressure By Evolutionary Algorithm Uspex, Mohammad Mahdi Davari Esfahani Dec 2017

Novel Superconducting Phases Of Materials Under Pressure By Evolutionary Algorithm Uspex, Mohammad Mahdi Davari Esfahani

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

Making solid metallic hydrogen proved elusive, even at pressures up to nearly 400 GPa. An alternative approach is to use chemical alloying as a means to exert additional pressure on hydrogen atoms. Following the recent breakthrough in predicting and synthesizing hydrogen sulfide with record-high Tc = 203 K [Drozdov et al. | Nature (2015)] and with the motivation of discovering high-temperature superconductors, evolutionary algorithm USPEX is employed to search for all stable compounds in the group-IV hydrides. This method has been successfully used to predict new materials that were confirmed experimentally, e.g. | Zhang et al. | Science (2013), Mannix …

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Adaptive Search Algorithms For Simulation Optimization In Discrete And Continuous Domains, Qi Fan Dec 2017

Adaptive Search Algorithms For Simulation Optimization In Discrete And Continuous Domains, Qi Fan

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

This thesis includes some newly-proposed adaptive search algorithms for simulation optimization in discrete and continuous domains. We first consider the ranking and selection problem of allocating a given simulation budget among a set of design alternatives in order to maximize the probability of correct selection. Previous research used to take static approaches to allocate certain number of simulation budget on different designs, i.e. pre-calculating the allocation plan before simulation, and among them, sequential optimal computing budget allocation (OCBA) shows the best allocation efficiency so far. Our approach, Dynamic Simulation Budget Allocation (DSBA), allocates this sampling budget dynamically by formulating this …

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Glycan Type Specificity In N-Linked Glycosylation: Implications For Highly Glycosylated Viral Surface Proteins, Artem Krantesvich Dec 2017

Glycan Type Specificity In N-Linked Glycosylation: Implications For Highly Glycosylated Viral Surface Proteins, Artem Krantesvich

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

Virtually every living cell is covered with glycoproteins. Most mammalian glycoproteins primarily bear N-linked glycans of complex type, having only a small fraction of hybrid glycans and barely any high-mannose glycans. However, some highly glycosylated proteins translated in mammalian cells have an unusually high fraction of high-mannose glycans. The goal of this thesis is to investigate the nature of the mechanisms behind this unusual distribution of glycan types and glycan type specificity for glycosylation sites. A well-studied example of the abnormally glycosylated protein is HIV envelope glycoprotein gp120, which usually has about 24 glycans, approximately half of them being of …

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Elusive Numbers. State Knowledge And Bureaucratic Organization In Chile (1750-1911), Andres Estefane-Jaramillo Dec 2017

Elusive Numbers. State Knowledge And Bureaucratic Organization In Chile (1750-1911), Andres Estefane-Jaramillo

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

This dissertation explores the trajectory of the Chilean State’s statistical projects from the mid-eighteenth century to the beginning of the twentieth century. It begins in a moment when the scientific concerns of the Enlightenment dovetailed with the State’s demand for knowledge after the dissolution of the Spanish Empire. It analyzes the construction of a specialized bureaucracy entrusted with the mission of producing the statistical information the Chilean State required for effective government. Due to the relational and spatial implications of producing official numbers, these inquiries opened up permanent spaces of interaction between the central institutions and the administrative peripheries of …

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Quantitative Imaging Of 3d Cerebral Microvascular Network Dynamics By Ultrahigh -Resolution Optical Coherence Doppler Tomography (Μodt), Jiang You Dec 2017

Quantitative Imaging Of 3d Cerebral Microvascular Network Dynamics By Ultrahigh -Resolution Optical Coherence Doppler Tomography (Μodt), Jiang You

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

Optical domain technologies can provide high spatiotemporal resolution for biomedical research and therefore attract tremendous interests in multiple disciplines including psychiatry, neurology, ophthalmology, oncology, urology and many more. Optical coherence tomography (OCT), after more than 20 years of development, has been becoming one of the most widely-used bio-optical modalities not only for laboratory-based research but also for clinical applications. For example, OCT becomes the standard of care for diagnosing glaucoma. Additionally, its derived velocimetry, optical coherence Doppler tomography (ODT), also demonstrates the unique capability of mapping cerebral blood flow velocity (CBFv) of vascular networks with capillary resolution (&phis;<6µm) and thus allows for the widespread utilization in numerous neurology studies. Although ODT has been widely used in biomedical research, there remain several technical limitations including the shallow penetration depth, low sensitivity for imaging slow flow in capillary and the measurement error due to Doppler angle. To address these challenges, viable solutions are proposed in this dissertation. Chapter 1 starts with a comprehensive review over basic principle of OCT and ODT. Chapter 2-4 explicitly address these OCT technical challenges, for instance, using a 1310nm super-luminescent Diode (SLD) laser source to extend optical penetration depth, utilizing optical contrast agent: intralipid to enhance ODT’s sensitivity for capillary flow detection, implementing numerical methods to extend ODT’s dynamic range and decouple Doppler angle. In addition to these technical improvements, Chapter 5-6 address two biomedical challenges in oncology and psychiatry. Specifically, Chapter 5 introduces a longitudinal optical access to rodent cerebral vasculature and a method of tumor boundary detection, which provides a powerful insight into the tumor progression. Chapter 6 reveals the close correlation between cocaine-elicited transient ischemic attack (TIA) and hypo-perfused cortex. Chapter 7 focuses on the development of multi-modality system and novel imaging scheme for the study of neurovascular coupling. Chapter 8 briefly concludes the contents presented in this dissertation and outlines the future development and potential applications of ODT. | 129 pages

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Performance Evaluation And Risk Management: Time Series Bootstrap Analysis Of The Mutual Funds And Banking Sectors, Lifa Huang Dec 2017

Performance Evaluation And Risk Management: Time Series Bootstrap Analysis Of The Mutual Funds And Banking Sectors, Lifa Huang

Graduate Theses and Dissertations

The Financial Services Modernization Act of 1999, also known as the Gramm–Leach–Bliley Act (“Act”), repealed a regulatory proscription in the Glass–Steagall Act of 1933 that prohibited commercial bank holding companies (BHCs) from underwriting most bonds, equities, and insurance policies. After the passage of the Act in November 1999, BHCs that converted to financial holding companies (FHCs) were allowed to engage in securities underwriting without restrictions. The first paper examines whether the removal of barriers to securities underwriting had an adverse impact on the overall stability of the financial sector, and thereby, contributed indirectly to the financial crisis of 2008. The …

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Methodologies For Solving Integrated Transportation And Scheduling Problems, Fereydoun Adbesh Dec 2017

Methodologies For Solving Integrated Transportation And Scheduling Problems, Fereydoun Adbesh

Graduate Theses and Dissertations

This research proposes novel solution techniques to optimize two real-world problems in the area of scheduling and transportation. We first consider a model for optimizing the operations of dredges. In this problem, scheduling and assignment decisions are integrated across a finite planning horizon. Additional constraints and problem elements explicitly considered include, but are not limited, to environmental work window restrictions, budget limitations, dredge operation rates and schedule-dependent dredge availability. Our approach makes use of Constraint Programming (CP) to obtain quality and robust solutions within an amount of time small enough to be useful to practitioners. The expanded feature set of …

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Development Of An Improved Synthesis Of S-D-Ribosyl-L-Homocysteine (Srh) And Progress Toward Srh Analogs Modified At The C3 Position, Emily Rouse Dec 2017

Development Of An Improved Synthesis Of S-D-Ribosyl-L-Homocysteine (Srh) And Progress Toward Srh Analogs Modified At The C3 Position, Emily Rouse

Master's Theses

Quorum sensing is a system that facilitates bacteria turning on and off gene expression depending on population density. System 2 quorum sensing is utilized by both Gram positive and Gram negative bacteria, and the quorum sensing molecule used in this system is AI-2. AI-2 is biosynthesized by the enzyme LuxS from the precursor SRH. This thesis describes an improved synthesis of SRH through the exploration of different protecting group strategies. The knowledge gained from the improved synthesis of SRH is then applied toward the synthesis of SRH analogues with increased steric bulk installed through use of a stereoselective anti-Mannich reaction. …

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Barriers To Implementation Of Lean Techniques In Printing Firms And The Impact Of Implementation, Sandeep Yellinedi Dec 2017

Barriers To Implementation Of Lean Techniques In Printing Firms And The Impact Of Implementation, Sandeep Yellinedi

Theses

Lean practices including 5S Lean Manufacturing, Six Sigma DMAIC and Value Stream Mapping are gaining more and more importance in a wide range of industries. Firms in various industries have implemented one or more of the techniques that comprise Lean techniques and have realized reduced wastes that in turn has contributed to increased profits. The researcher, being associated with the field of printing, has observed the Lean techniques practicing trends in the printing industry. This report builds upon the previously published research that has examined the implementation of Lean Methodologies, including studies that have investigated the impact of the adoption …

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The Design Of A Custom 32-Bit Simd Enhanced Digital Signal Processor, Shashank Simha Dec 2017

The Design Of A Custom 32-Bit Simd Enhanced Digital Signal Processor, Shashank Simha

Theses

For a number of years, the hardware industry has seen a drastic rise in embedded applications. Thanks to the Internet of Things (IoT) revolution, a majority of these embedded applications are shifting towards the usage of simple hardware capable of running on batteries, while being able to handle complex data and implement complex algorithms. Translating these requirements to digital design terms, the hardware is expected to have high power efficiency, be tiny and simple enough, while being capable of meeting realtime constraints and process mathematical algorithms. Looking at some of the modern DSPs, most of them have been targeting high …

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Image Down-Scaler Using The Box Filter Algorithm, Vaishnavi Parthipan Dec 2017

Image Down-Scaler Using The Box Filter Algorithm, Vaishnavi Parthipan

Theses

One of the indispensable aspects of digital image processing is the requirement of varied image resolutions. To achieve varied resolution, scaling comes into picture. Two important applications of scaling is good pictorial quality for human interpretation and processing of digital images for storage, transmission and for representation of autonomous machine perception. This paper focuses on the transmission application. The size of the image if reduced occupies less space in the communication medium thus reducing the bandwidth requirement. And also the server space and the processing power of the image is reduced greatly. The standard for digital television transmission over terrestrial, …

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An Uncommon Use For An Uncommon Press: Approaching Object-Based Stem Education In Cultural Institutions By Way Of A Reconstructed English Common Press, Daniel B. Krull Dec 2017

An Uncommon Use For An Uncommon Press: Approaching Object-Based Stem Education In Cultural Institutions By Way Of A Reconstructed English Common Press, Daniel B. Krull

Theses

The Uncommon Press Project was a cross-departmental, multi-disciplinary capstone project by students from the Kate Gleason College of Engineering and the College of Liberal Arts at Rochester Institute of Technology which aimed to create a historically accurate reconstruction of a circa 1790 English common press for the Cary Graphic Arts Collection. As a member of the team undertaking this project, I was involved in the research, materials acquisition, construction, and social media engagement efforts. In addition to my role as part of this team, I desired, as an individual scholar, to learn how a reconstructed press can serve as an …

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Asian Extremes: Experience And Exchange In The Development Of Meteorological Knowledge C. 1840-1930, Fiona Williamson, Clive Wilkinson Dec 2017

Asian Extremes: Experience And Exchange In The Development Of Meteorological Knowledge C. 1840-1930, Fiona Williamson, Clive Wilkinson

Research Collection School of Social Sciences

On 29 July 1939, the aircraft carrier HMS Eagle was off the northern entrance of the Formosa Strait, approximately 25⁰N, 121⁰E. The ship’s meteorological officer was formulating the current synoptic weather situation, which included a typhoon to the south or south-east of Formosa with a second typhoon much further east in about 144⁰E. It might be expected that in 1939, the existence and position of a typhoon could be corroborated easily by contemporary ‘experts’ situated nearby. However ‘The utmost confusion prevailed’ noted the officer ‘among the experts at Zikawei, Manila & Hong Kong today …I think there is no doubt …

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Inventory Control By Using Fuzzy Set Theory An Applied Research At The Baghdad Soft Drinks Company, Wakas Saad Khalaf, Abdullah Jasim‎ Dec 2017

Inventory Control By Using Fuzzy Set Theory An Applied Research At The Baghdad Soft Drinks Company, Wakas Saad Khalaf, Abdullah Jasim‎

Journal of Economics and Administrative Sciences

The production companies in the Iraqi industry environment facing many of the problems related to the management of inventory and control In particular in determining the quantities inventory that should be hold it. Because these companies adoption on personal experience and some simple mathematical methods which lead to the identification of inappropriate quantities of inventory. This research aims to identify the economic quantity of production and purchase for the Pepsi can 330ml and essential components in Baghdad soft drinks Company in an environment dominated by cases of non ensure and High fluctuating as a result of fluctuating demand volumes and …

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A Comparison Between Methods Of Laplace Estimators And The Robust Huber For Estimate Parameters Logistic Regression Model, Eman Hassan Ahmed, Dhamyaa Hamid Shihab Dec 2017

A Comparison Between Methods Of Laplace Estimators And The Robust Huber For Estimate Parameters Logistic Regression Model, Eman Hassan Ahmed, Dhamyaa Hamid Shihab

Journal of Economics and Administrative Sciences

The logistic regression model regarded as the important regression Models ,where of the most interesting subjects in recent studies due to taking character more advanced in the process of statistical analysis . The ordinary estimating methods is failed in dealing with data that consist of the presence of outlier values and hence on the absence of such that have undesirable effect on the result. We will review in this research to estimate parameters of logistic regression model these methods are Laplace Estimators (LP-) and Huber estimator (H). Was conducted to compare between two methods through the simulation and using comparison …

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Comparing Bayes Estimation With Maximum Likelihood Estimation Of Generalized Inverted Exponential Distribution In Case Of Fuzzy Data, Qutaiba Naief Nayef Al-Kazaz, Hawraa J. Al-Saadi Dec 2017

Comparing Bayes Estimation With Maximum Likelihood Estimation Of Generalized Inverted Exponential Distribution In Case Of Fuzzy Data, Qutaiba Naief Nayef Al-Kazaz, Hawraa J. Al-Saadi

Journal of Economics and Administrative Sciences

In this paper, the generalized inverted exponential distribution is considered as one of the most important distributions in studying failure times. A shape and scale parameters of the distribution have been estimated after removing the fuzziness that characterizes its data because they are triangular fuzzy numbers. To convert the fuzzy data to crisp data the researcher has used the centroid method. Hence the studied distribution has two parameters which show a difficulty in separating and estimating them directly of the MLE method. The Newton-Raphson method has been used. For the Bayesian method, the gamma distribution has been proposed as a …

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Barrier Properties Of Polymer Nanocomposites With Graphene Oxide And Its Derivatives: Mechanism And Applications In Anticorrosive Coatings, Yidan Guan Dec 2017

Barrier Properties Of Polymer Nanocomposites With Graphene Oxide And Its Derivatives: Mechanism And Applications In Anticorrosive Coatings, Yidan Guan

Dissertations

Metallic devices made from steel or aluminum are subjected to deterioration by environmental contaminants over time. As one of the corrosion control methods, organic coatings show many advantages due to their low cost, versatility, decoration aesthetics and effective protections. Corrosion protection theories and failure modes of organic coatings are still not fully understood due to complicated interactions in the coating-metal-environment system, however, it is widely agreed that the barrier nature of polymeric materials towards aggressive species, such as oxygen, water, electrolyte, plays a key role. Improved barrier property of polymer nanocomposites (PNCs) with two-dimensional (2D) carbon filler, graphene and graphene …

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3d Printing Concrete Structures And Verifying Integrity Of Their G-Code Instructions: Border Wall A Case Study, Jason Breland Dec 2017

3d Printing Concrete Structures And Verifying Integrity Of Their G-Code Instructions: Border Wall A Case Study, Jason Breland

Dissertations

Thanks to advances in Additive Manufacturing (AM) technology and continued research by academics and entrepreneurs alike, the ability to “3d print” permanent concrete structures such as homes or offices is now a reality. Generally, AM is the process that allows for a 3d model of an object to be converted into hardware instructions to generate that object layer by layer using a malleable medium such as a plastic. Specifically, large scale concrete AM can now generate a structure, such as a building, layer by layer more quickly and efficiently than traditional construction methods [6, 39]. This innovative, semi-autonomous process promises …

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Eigenblades: Application Of Computer Vision And Machine Learning For Mode Shape Identification, Alex W. La Dec 2017

Eigenblades: Application Of Computer Vision And Machine Learning For Mode Shape Identification, Alex W. La

Theses and Dissertations

On August 27, 2016, Southwest Airlines flight 3472 from New Orleans to Orlando had to perform an emergency landing when a fan blade separated from the engine hub and destroyed the cowling and punctured the fuselage. Initial findings from the metallurgical examination conducted in the National Transpiration Safety Board Materials Laboratory found that the fracture surface of the missing blade showed curving crack arrest lines consistent with fatigue crack growth. Fatigue is often cause by resonate vibrations. Modal analysis is a method that can model the natural frequencies and bending modes of turbomachinery blades. When performing modal analysis with finite …

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Temperature-Dependent Models Of Development And Survival Of An Insect Pest Of African Tropical Highlands, The Coffee Antestia Bug Antestiopsis Thunbergii (Hemiptera: Pentatomidae), Abdelmutalab G.A. Azrag, Lucy K. Murungi, Henri E.Z. Tonnang, Dickson Mwenda, Régis Babin Dec 2017

Temperature-Dependent Models Of Development And Survival Of An Insect Pest Of African Tropical Highlands, The Coffee Antestia Bug Antestiopsis Thunbergii (Hemiptera: Pentatomidae), Abdelmutalab G.A. Azrag, Lucy K. Murungi, Henri E.Z. Tonnang, Dickson Mwenda, Régis Babin

All Peer-Reviewed Publications

The antestia bug Antestiopsis thunbergii (Hemiptera: Pentatomidae) is a major pest of Arabica coffee in African tropical highlands. It feeds on coffee plant vegetative parts and berries leading to a direct reduction in coffee yield and quality. This study aimed to determine A. thunbergii thermal requirements, and to obtain new information on the pest demography as influenced by temperature. Temperature-dependent models were developed using the Insect Life Cycle Modelling software (ILCYM) through a complete life table study at seven constant temperatures in the range 18–32 °C. Non-linear functions were fitted to A. thunbergii development, mortality, fecundity and senescence. Model parameters …

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The Stripe 82 Massive Galaxy Project. Iii. A Lack Of Growth Among Massive Galaxies, Kevin Bundy, Alexie Leauthaud, Shun Saito, Claudia Maraston, David A. Wake, Daniel Thomas Dec 2017

The Stripe 82 Massive Galaxy Project. Iii. A Lack Of Growth Among Massive Galaxies, Kevin Bundy, Alexie Leauthaud, Shun Saito, Claudia Maraston, David A. Wake, Daniel Thomas

Physics Faculty Research & Creative Works

The average stellar mass (M*) of high-mass galaxies (log M*/M⊙ > 11.5) is expected to grow by ∼30% since z ~ 1, largely through ongoing mergers that are also invoked to explain the observed increase in galaxy sizes. Direct evidence for the corresponding growth in stellar mass has been elusive, however, in part because the volumes sampled by previous redshift surveys have been too small to yield reliable statistics. In this work, we make use of the Stripe 82 Massive Galaxy Catalog (S82-MGC) to build a mass-limited sample of 41,770 galaxies log M*/M⊙ …

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Estimating The Contribution Of Dynamical Ejecta In The Kilonova Associated With Gw170817, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov Dec 2017

Estimating The Contribution Of Dynamical Ejecta In The Kilonova Associated With Gw170817, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov

Physics & Astronomy Faculty Publications

The source of the gravitational-wave (GW) signal GW170817, very likely a binary neutron star merger, was also observed electromagnetically, providing the first multi-messenger observations of this type. The two-week-long electromagnetic (EM) counterpart had a signature indicative of an r-process-induced optical transient known as a kilonova. This Letter examines how the mass of the dynamical ejecta can be estimated without a direct electromagnetic observation of the kilonova, using GW measurements and a phenomenological model calibrated to numerical simulations of mergers with dynamical ejecta. Specifically, we apply the model to the binary masses inferred from the GW measurements, and use the resulting …

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Receiver Function Imaging Of Mantle Transition Zone Discontinuities Beneath The Tanzania Craton And Adjacent Segments Of The East African Rift System, Muchen Sun, Kelly H. Liu, Xiaofei Fu, Stephen S. Gao Dec 2017

Receiver Function Imaging Of Mantle Transition Zone Discontinuities Beneath The Tanzania Craton And Adjacent Segments Of The East African Rift System, Muchen Sun, Kelly H. Liu, Xiaofei Fu, Stephen S. Gao

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The mantle transition zone (MTZ) discontinuities beneath the Tanzania Craton and the Eastern and Western Branches of the East African Rift System are imaged by stacking over 7,100 receiver functions. The mean thickness of the MTZ beneath the Western Branch and Tanzania Craton is about 252 km, which is comparable to the global average and is inconsistent with the existence of present-day thermal upwelling originating from the lower mantle. In contrast, beneath the Eastern Branch, an up to 30 km thinning of the MTZ is observed and is attributable to upwelling of higher temperature materials from either the upper MTZ …

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Topography Of The Mantle Transition Zone Discontinuities Beneath Alaska And Its Geodynamic Implications: Constraints From Receiver Function Stacking, Haider H. Dahm, Stephen S. Gao, Fansheng Kong, Kelly H. Liu Dec 2017

Topography Of The Mantle Transition Zone Discontinuities Beneath Alaska And Its Geodynamic Implications: Constraints From Receiver Function Stacking, Haider H. Dahm, Stephen S. Gao, Fansheng Kong, Kelly H. Liu

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The 410 and 660 km discontinuities (d410 and d660, respectively) beneath Alaska and adjacent areas are imaged by stacking 75,296 radial receiver functions recorded by 438 broadband seismic stations with up to 30 years of recording period. When the 1-D IASP91 Earth model is used for moveout correction and time depth conversion, significant and spatially systematic variations in the apparent depths of the d410 and d660 are observed. The mean apparent depth of the d410 and d660 for the entire study area is 417 ± 12 km and 665 ± 12 km, respectively, and the mean mantle transition zone (MTZ) …

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Urban Youth Perceptions Of Agriculture, Sharon Jean-Philippe, Jennifer Richards, Kimberly Gwinn, Caula Beyl Dec 2017

Urban Youth Perceptions Of Agriculture, Sharon Jean-Philippe, Jennifer Richards, Kimberly Gwinn, Caula Beyl

Journal of Youth Development

To change public perceptions, particularly from urban populations, of agriculture and natural resources (ANR) fields, the University of Tennessee developed a model of strategic educational recruitment to extend beyond traditional college fair experiences to educate underrepresented candidates. The High School Agricultural Education Initiative (HSAI) provided 10th-grade students with opportunities to: (a) gain knowledge of and appreciation for disciplines in agriculture and natural resources, (b) learn about college admissions standards, (c) network with college students and staff to learn about campus resources, and (d) understand how a college education improves professional opportunities. The HSAI (n = 122) was effective at increasing …

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