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2018

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Articles 2671 - 2700 of 13646

Full-Text Articles in Physical Sciences and Mathematics

Galaxy And Mass Assembly (Gama): The Signatures Of Galaxy Interactions As Viewed From Small-Scale Galaxy Clustering, M. L.P. Gunawardhana, P. Norberg, I. Zehavi, D. J. Farrow, J. Loveday, A. M. Hopkins, L. J.M. Davies, L. Wang, M. Alpaslan, J. Bland-Hawthorn, S. Brough, Benne W. Holwerda, M. S. Owers, A. H. Wright Sep 2018

Galaxy And Mass Assembly (Gama): The Signatures Of Galaxy Interactions As Viewed From Small-Scale Galaxy Clustering, M. L.P. Gunawardhana, P. Norberg, I. Zehavi, D. J. Farrow, J. Loveday, A. M. Hopkins, L. J.M. Davies, L. Wang, M. Alpaslan, J. Bland-Hawthorn, S. Brough, Benne W. Holwerda, M. S. Owers, A. H. Wright

Faculty and Staff Scholarship

Statistical studies of galaxy-galaxy interactions often utilize net change in physical properties of progenitors as a function of the separation between their nuclei to trace both the strength and the observable time-scale of their interaction. In this study, we use two-point auto-, cross-, and mark-correlation functions to investigate the extent to which small-scale clustering properties of star-forming galaxies can be used to gain physical insight into galaxy-galaxy interactions between galaxies of similar optical brightness and stellar mass. The Ha star formers, drawn from the highly spatially complete Galaxy And Mass Assembly (GAMA) survey, show an increase in clustering at small …

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Ecology And Population Dynamics Of Salmonids In The Columbia River: Response Of Fishes To Anthropogenic Change In A Large Riverscape, Timothy Sean Elder Sep 2018

Ecology And Population Dynamics Of Salmonids In The Columbia River: Response Of Fishes To Anthropogenic Change In A Large Riverscape, Timothy Sean Elder

Dissertations and Theses

Freshwater ecosystems and the species that reside therein are disproportionately imperiled compared to terrestrial systems. Over the past 150 years, the Columbia River basin in the western United States has gone from one of the most productive and abundant salmon watersheds in the world, to having just a small fraction of its former salmon abundance. The cause of declines in salmon productivity and abundance are related to overlapping and confounding stressors including changes in large-scale climatic patterns and anthropogenic alterations within and adjacent to the Columbia River. Four main anthropogenic stressors have been identified as the leading causes of salmonid …

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On The Dynamics Of Near-Extremal Black Holes, Pranjal Nayak, Ashish Shukla, Ronak M. Soni, Sandip P. Trivedi, V. Vishal Sep 2018

On The Dynamics Of Near-Extremal Black Holes, Pranjal Nayak, Ashish Shukla, Ronak M. Soni, Sandip P. Trivedi, V. Vishal

Physics and Astronomy Faculty Publications

We analyse the dynamics of near-extremal Reissner-Nordström black holes in asymptotically four-dimensional Anti de Sitter space (AdS4). We work in the spherically symmetric approximation and study the thermodynamics and the response to a probe scalar field. We find that the behaviour of the system, at low energies and to leading order in our approximations, is well described by the Jackiw-Teitelboim (JT) model of gravity. In fact, this behaviour can be understood from symmetry considerations and arises due to the breaking of time reparametrisation invariance. The JT model has been analysed in considerable detail recently and related to the …

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Separated Fringe Packet Observations With The Chara Array. Iii. The Very High-Eccentricity Binary Hr 7345, Chris D. Farrington, Francis C. Fekel, Gail Schaefer, Theo A. Ten Brummelaar Sep 2018

Separated Fringe Packet Observations With The Chara Array. Iii. The Very High-Eccentricity Binary Hr 7345, Chris D. Farrington, Francis C. Fekel, Gail Schaefer, Theo A. Ten Brummelaar

Information Systems and Engineering Management Research Publications

After an 11-year observing campaign, we present the combined visual–spectroscopic orbit of the formerly unremarkable bright star HR 7345 (HD 181655, HIP 94981, GJ 754.2). Using the Separated Fringe Packet method with the CHARA Array, we were able to determine a difficult-to-complete orbital period of 331.609 ± 0.004 days. The 11-month period causes the system to be hidden from interferometric view behind the Sun for three years at a time. Due to the high-eccentricity orbit of about 90% of a year, after 2018 January the periastron phase will not be observable again until late 2021. Hindered by its extremely high …

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Beam Energy Dependence Of Rapidity-Even Dipolar Flow In Au + Au Collisions, J. Adam, L. Adamczyk, J. R. Adams, James K. Adkins, G. Agakishiev, M. M. Aggarwal, Z. Ahammed, N. N. Ajitanand, I. Alekseev, D. M. Anderson, R. Aoyama, A. Aparin, D. Arkhipkin, E. C. Aschenauer, M. U. Ashraf, F. Atetalla, A. Attri, G. S. Averichev, X. Bai, V. Bairathi, K. Barish, A. J. Bassill, A. Behera, R. Bellwied, A. Bhasin, A. K. Bhati, J. Bielcik, J. Bielcikova, L. C. Bland, I. G. Bordyuzhin, Renee H. Fatemi, Suvarna Ramachandran Sep 2018

Beam Energy Dependence Of Rapidity-Even Dipolar Flow In Au + Au Collisions, J. Adam, L. Adamczyk, J. R. Adams, James K. Adkins, G. Agakishiev, M. M. Aggarwal, Z. Ahammed, N. N. Ajitanand, I. Alekseev, D. M. Anderson, R. Aoyama, A. Aparin, D. Arkhipkin, E. C. Aschenauer, M. U. Ashraf, F. Atetalla, A. Attri, G. S. Averichev, X. Bai, V. Bairathi, K. Barish, A. J. Bassill, A. Behera, R. Bellwied, A. Bhasin, A. K. Bhati, J. Bielcik, J. Bielcikova, L. C. Bland, I. G. Bordyuzhin, Renee H. Fatemi, Suvarna Ramachandran

Physics and Astronomy Faculty Publications

New measurements of directed flow for charged hadrons, characterized by the Fourier coefficient v1, are presented for transverse momenta pT, and centrality intervals in Au+Au collisions recorded by the STAR experiment for the center-of-mass energy range √sNN=7.7–200 GeV. The measurements underscore the importance of momentum conservation, and the characteristic dependencies on √sNN, centrality and pT are consistent with the expectations of geometric fluctuations generated in the initial stages of the collision, acting in concert with a hydrodynamic-like expansion. The centrality and pT dependencies of v1even …

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Beryllium And Indium Activation Measurements Of Total Neutron Yield From A Pulsed Photoneutron Source, Kristina K. Brown Sep 2018

Beryllium And Indium Activation Measurements Of Total Neutron Yield From A Pulsed Photoneutron Source, Kristina K. Brown

Physics & Astronomy ETDs

A pulsed photoneutron source consisting of a beryllium sphere and a 5 MeV endpoint 30 ns bremsstrahlung beam emanating from the Mercury pulsed-power source was assembled and tested in October 2017 at the Naval Research Laboratory (NRL) in Washington, D.C. [1]. The objective of this experiment was to verify the feasibility of using a pulsed power source to create a large number of photoneutrons in a short period of time, leveraging the low photoneutron production threshold of 9Be to maximize neutron production. Several diagnostics were deployed to characterize the source and target, including indium and beryllium activation detectors that measured …

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Ability Of Ir And Nmr Spectral Data To Distinguish Between A Tetrel Bond And A Hydrogen Bond, Steve Scheiner Sep 2018

Ability Of Ir And Nmr Spectral Data To Distinguish Between A Tetrel Bond And A Hydrogen Bond, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

The placement of a nucleophile X along the R-CH3 axis of a methyl group can be described as either a trifurcated H-bond or as a tetrel bond between C and X. Quantum calculation of the vibrational and NMR spectral features of a number of systems are used to provide a framework by which to distinguish between the presence of a tetrel or H-bond. Both cationic and neutral methyl-containing Lewis acids (SMe3+, NMe4+, SMe2) are paired with both neutral and anionic Lewis bases (NH3, OH2, OCHNH2, OCH3-, OH-, HCOO-). As the base is moved away from the R-CH3 axis of the …

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Effects Of Radiation Field Geometry On Line Driven Disc Winds, Sergei Dyda, Daniel Proga Sep 2018

Effects Of Radiation Field Geometry On Line Driven Disc Winds, Sergei Dyda, Daniel Proga

Physics & Astronomy Faculty Research

We study line driven winds for models with different radial intensity profiles: standard Shakura–Sunyaev radiating thin discs, uniform intensity discs, and truncated discs where driving radiation is cut-off at some radius. We find that global outflow properties depend primarily on the total system luminosity but truncated discs can launch outflows with ∼2 times higher mass flux and ∼50 per cent faster outflow velocity than non-truncated discs with the same total radiation flux. Streamlines interior to the truncation radius are largely unaffected and carry the same momentum flux as non-truncated models whereas those far outside the truncation radius effectively carry no …

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Observed Differences Between Near-Surface Air And Skin Temperatures Using Satellite And Ground-Based Data, Satya Prakash, Farjana Shati, Hamidreza Norouzi, Reginald Blake Sep 2018

Observed Differences Between Near-Surface Air And Skin Temperatures Using Satellite And Ground-Based Data, Satya Prakash, Farjana Shati, Hamidreza Norouzi, Reginald Blake

Publications and Research

Accurate estimates of long-term land surface temperature (Ts) and near-surface air temperature (Ta) at finer spatio-temporal resolutions are crucial for surface energy budget studies, for environmental applications, for land surface model data assimilation, and for climate change assessment and its associated impacts. The Atmospheric Infrared Sounder (AIRS) and Moderate Resolution Imaging Spectroradiometer (MODIS) sensors onboard the Aqua satellite provide a unique opportunity to estimate both temperatures twice daily at the global scale. In this study, differences between Ta and Ts were assessed locally over regions of North America from 2009 to 2013 …

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Increasing The Accuracy Of A Differential Solution Of A Differential Problem By The Method Of Concentrating A Sequence Of Networks, A Otarov Sep 2018

Increasing The Accuracy Of A Differential Solution Of A Differential Problem By The Method Of Concentrating A Sequence Of Networks, A Otarov

Karakalpak Scientific Journal

The method of increasing the accuracy of the difference solution of the differential problem based on the use of a thickened sequence of grids is presented in the article. The method is illustrated with the solution of a given boundary-value problem posed for an ordinary second-order differential equation.

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Composition Sorbents For Sewage Treatment Based On Karakalpakstan Bentonites, A Abdikamalova Sep 2018

Composition Sorbents For Sewage Treatment Based On Karakalpakstan Bentonites, A Abdikamalova

Karakalpak Scientific Journal

The article presents the results of the investigation of the adsorption ability of bentonite clays of Karakalpakstan in relation to ions of heavy metals and petroleum products. It has been established that thermal activation in the presence of plant material waste leads to a change in the surface properties of bentonites, thereby increasing their adsorption properties with respect to various pollutants of waste water.

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Creation Of A Numerical Mathematical Model Of Geofiltration Processes And Its Adaptation For Solving Epignosic And Forecast Problems (In Terms Of Gurlen District Of Khorezm Region), Tolkun Mirakhmedov Sep 2018

Creation Of A Numerical Mathematical Model Of Geofiltration Processes And Its Adaptation For Solving Epignosic And Forecast Problems (In Terms Of Gurlen District Of Khorezm Region), Tolkun Mirakhmedov

Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences

The article considers the creation of a mathematical model of geofiltration processes in Gurlen District. Methods for calculating and developing a mathematical model and algorithms were carried out, and applied software was developed, and the developed geofiltration mathematical model was adapted to solve the epignosic and forecast problems of the area under consideration.

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The Optimal Risk Of Estimator Of Conditional Distribution Function In A Model Of Heteroscedastic Regression With Weakly Dependent Observations, Farkhad Abdikalikov, Laura Reymova Sep 2018

The Optimal Risk Of Estimator Of Conditional Distribution Function In A Model Of Heteroscedastic Regression With Weakly Dependent Observations, Farkhad Abdikalikov, Laura Reymova

Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences

Paper is devoted to estimation of conditional distribution function in heteroscedastical regression model, in which responses are α-mixing random variables. It is found the expression for mean square deviation of estimator and optimal window width sequence.

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Thermal Evolution Modification Due To Radio-Wave Production Inside Rotating Magnetized Ns, Pulat Tadjimuratov Sep 2018

Thermal Evolution Modification Due To Radio-Wave Production Inside Rotating Magnetized Ns, Pulat Tadjimuratov

Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences

We study effect of additional cooling mechanism on the thermal evolution of rotating magnetized neutron star (NS). The influence of general relativistic effects on charge distribution inside a NS leads to the qualitative distinction of space charge distribution inside the conducting crust from that inside the superconducting core which may play a source of a possible mechanism of radio-wave radiation production in the intermediate medium inside a rotating neutron star. This radiation may interact the matter of the neutron star and energy of the electromagnetic radiation can be transformed into the heating energy. The intensity of radio-wave radiation produced inside …

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Amidoalkylation Of Aromatic Compounds, Mukhabbat Yuldasheva, Khurshida Turaeva, Tursunali Kholiqov Sep 2018

Amidoalkylation Of Aromatic Compounds, Mukhabbat Yuldasheva, Khurshida Turaeva, Tursunali Kholiqov

Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences

As the result of systematical investigation of amidomethylation reaction benzene, toluene, isomeric xylenes, benzodioxane-1,4, mono- and dimethyl ethers of resorcinole, dimethyl ethers of hydroquinone with methylol and ethylol derivatives amides and imides, acetonitrile, benzonitrile and paraform the amidomethyl derivatives have been obtained and also influence of different factors on their yields and direction of investigated reactions was determined. Synthesis of amidomethyl derivatives of aromatic hydrocarbons, ethers dihydricpenols and most probable reaction mechanism was proposed.

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The Extent Of Destruction Of Landscapes In The Tashkent Region, Shavkat Sharipov, Kamoliddin Khakimov, Davronbek Boymurodov Sep 2018

The Extent Of Destruction Of Landscapes In The Tashkent Region, Shavkat Sharipov, Kamoliddin Khakimov, Davronbek Boymurodov

Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences

The article points to those parts of landscape of the Tashkent region that have become unfit for use in the economy - destroyed lands and their extension as a result of natural and anthropogenic factors.

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A Circular Planetarium As A Spatial Visual Musical Instrument, Dale E. Parson Ph.D. Sep 2018

A Circular Planetarium As A Spatial Visual Musical Instrument, Dale E. Parson Ph.D.

Computer Science and Information Technology Faculty

Planetariums have been home to spatial visual music for over sixty years. Advanced technology in spatial sound such as sound field and wave field systems are superseding channel-based systems as areas for research. Nevertheless, there is room for invention in immersive spatial visual music in a channel-based planetarium. Circular seating minimizes problems with sonic reflections from circular walls suffered by unidirectional theatre seating arrangements. Circular seating supports dynamic permutation of channel-to-speaker routing as a corrective and compositional measure. Full dome projection of visuals gives inherent support for graphics-to-music spatial correlation and related immersive effects. This paper is a case study …

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Synthesis And Characterization Of Alkynyl-Substituted Boron Formazanate Dyes, Alex Van Belois Sep 2018

Synthesis And Characterization Of Alkynyl-Substituted Boron Formazanate Dyes, Alex Van Belois

Electronic Thesis and Dissertation Repository

This thesis outlines the synthesis and characterization of the first alkynyl-substituted boron formazanate complexes and explores the electronic and structural changes that occur in these systems as a result of chemical modification at the boron centre. An alkynyl-substituted complex appended with a redox-active handle is also described, and the chemical reduction and oxidation of this system is explored. Finally, a model reaction is examined as a proof of concept toward the post-synthetic modification of these boron formazanate systems through copper(I)-assisted alkyne-azide cycloaddition chemistry. Exploiting chemistry at the boron centre opens up new possibilities toward incorporating function onto the boron formazanate …

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The Firece Green Fire: Vol. 9 Issue 1, Wofford College Environmental Studies Program Sep 2018

The Firece Green Fire: Vol. 9 Issue 1, Wofford College Environmental Studies Program

The Fierce Green Fire

No abstract provided.

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An Overview Of Dynamic Heterogeneous Oxidations In The Troposphere, Elizabeth A. Pillar-Little, Marcelo I. Guzman Sep 2018

An Overview Of Dynamic Heterogeneous Oxidations In The Troposphere, Elizabeth A. Pillar-Little, Marcelo I. Guzman

Chemistry Faculty Publications

Due to the adverse effect of atmospheric aerosols on public health and their ability to affect climate, extensive research has been undertaken in recent decades to understand their sources and sinks, as well as to study their physical and chemical properties. Atmospheric aerosols are important players in the Earth’s radiative budget, affecting incoming and outgoing solar radiation through absorption and scattering by direct and indirect means. While the cooling properties of pure inorganic aerosols are relatively well understood, the impact of organic aerosols on the radiative budget is unclear. Additionally, organic aerosols are transformed through chemical reactions during atmospheric transport. …

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Short-Term Low Salinity Mitigates Effects Of Oil And Dispersant On Juvenile Eastern Oysters: A Laboratory Experiment With Implications For Oil Spill Response Activities, Meagan N. Schrandt, Sean Powers, F.Scott Rikard, Wilawan Thongda, Eric Peatman Sep 2018

Short-Term Low Salinity Mitigates Effects Of Oil And Dispersant On Juvenile Eastern Oysters: A Laboratory Experiment With Implications For Oil Spill Response Activities, Meagan N. Schrandt, Sean Powers, F.Scott Rikard, Wilawan Thongda, Eric Peatman

University Faculty and Staff Publications

Following the Deepwater Horizon oil spill, eastern oyster (Crassostrea virginica) reefs in the northern Gulf of Mexico were exposed to oil and various associated clean-up activities that may have compromised oyster reef health. Included in the exposure was oil, dispersant, and in some locales, atypical salinity regimes. Oil and dispersants can be detrimental to oysters and the effects of salinity depend on the level. In addition to these extrinsic factors, genetic diversity of oyster populations may help the oysters respond to stressors, as demonstrated in other systems. We used a 3×3×2 factorial design to experimentally examine the effects …

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The Assemblage Structure And Trophic Ecology Of A Deep-Pelagic Fish Family (Platytroctidae) In The Gulf Of Mexico, Michael Novotny Sep 2018

The Assemblage Structure And Trophic Ecology Of A Deep-Pelagic Fish Family (Platytroctidae) In The Gulf Of Mexico, Michael Novotny

HCNSO Student Theses and Dissertations

Members of the family Platytroctidae (tubeshoulders) are found throughout the meso- and bathypelagic waters of the World Ocean. Due to the lack of specimens collected globally, this taxon has received little attention, despite recent evidence suggesting its predominance in the bathypelagic biome. Prior to this study, only four species had been reported in the Gulf of Mexico’s (GoM) highly diverse deep-pelagic ecosystem. An extensive meso- and bathypelagic trawl series in the GoM allowed a detailed examination of this family, which included analyses of species composition, abundance, vertical distribution, sex ratios, and trophic ecology. A total of 16 species were collected, …

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End-To-End Convolutional Neural Network Model For Gear Fault Diagnosis Based On Sound Signals, Yong Yao, Honglei Wang, Shaobo Li, Zhongnhao Liu, Gui Gui, Yabo Dan, Jianjun Hu Sep 2018

End-To-End Convolutional Neural Network Model For Gear Fault Diagnosis Based On Sound Signals, Yong Yao, Honglei Wang, Shaobo Li, Zhongnhao Liu, Gui Gui, Yabo Dan, Jianjun Hu

Faculty Publications

Currently gear fault diagnosis is mainly based on vibration signals with a few studies on acoustic signal analysis. However, vibration signal acquisition is limited by its contact measuring while traditional acoustic-based gear fault diagnosis relies heavily on prior knowledge of signal processing techniques and diagnostic expertise. In this paper, a novel deep learning-based gear fault diagnosis method is proposed based on sound signal analysis. By establishing an end-to-end convolutional neural network (CNN), the time and frequency domain signals can be fed into the model as raw signals without feature engineering. Moreover, multi-channel information from different microphones can also be fused …

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Enhancement Of Triplet-Sensitized Upconversion In Rigid Polymers Via Singlet Exciton Sink Approach, Steponas Raišys, Saulius Juršėnas, Yoan C. Simon, Christoph Weder, Karolis Kazlauskas Sep 2018

Enhancement Of Triplet-Sensitized Upconversion In Rigid Polymers Via Singlet Exciton Sink Approach, Steponas Raišys, Saulius Juršėnas, Yoan C. Simon, Christoph Weder, Karolis Kazlauskas

Faculty Publications

To increase the practical usefulness of solid-state sensitized upconversion (UC) materials as components of solar energy harvesting systems, it is important to identify and suppress loss mechanisms, and increase the UC quantum yield (ΦUC). Here we focus on a benchmark UC system consisting of the emitter 9,10-diphenylanthracene (DPA) and the sensitizer platinum octaethylporphyrin (PtOEP) in a rigid poly(methyl methacrylate) (PMMA) matrix, and show that one of the major losses originates from Förster resonant energy transfer (FRET) from DPA back to PtOEP. Even though DPA emission lies within the PtOEP transparency window, the quantitative assessment of singlet exciton diffusion …

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Break The Dead End Of Dynamic Slicing: Localizing Data And Control Omission Bug, Yun Lin, Jun Sun, Lyly Tran, Guangdong Bai, Haijun Wang, Jin Song Dong Sep 2018

Break The Dead End Of Dynamic Slicing: Localizing Data And Control Omission Bug, Yun Lin, Jun Sun, Lyly Tran, Guangdong Bai, Haijun Wang, Jin Song Dong

Research Collection School Of Computing and Information Systems

Dynamic slicing is a common way of identifying the root cause when a program fault is revealed. With the dynamic slicing technique, the programmers can follow data and control flow along the program execution trace to the root cause. However, the technique usually fails to work on omission bugs, i.e., the faults which are caused by missing executing some code. In many cases, dynamic slicing over-skips the root cause when an omission bug happens, leading the debugging process to a dead end. In this work, we conduct an empirical study on the omission bugs in the Defects4J bug repository. Our …

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Pfix: Fixing Concurrency Bugs Based On Memory Access Patterns, Huarui Lin, Zan Wang, Shuang Liu, Jun Sun, Dongdi Zhang, Guangning Wei Sep 2018

Pfix: Fixing Concurrency Bugs Based On Memory Access Patterns, Huarui Lin, Zan Wang, Shuang Liu, Jun Sun, Dongdi Zhang, Guangning Wei

Research Collection School Of Computing and Information Systems

Concurrency bugs of a multi-threaded program may only manifest with certain scheduling, i.e., they are heisenbugs which are observed only from time to time if we execute the same program with the same input multiple times. They are notoriously hard to fix. In this work, we propose an approach to automatically fix concurrency bugs. Compared to previous approaches, our key idea is to systematically fix concurrency bugs by inferring locking policies from failure inducing memory-access patterns. That is, we automatically identify memory-access patterns which are correlated with the manifestation of the bug, and then conjecture what is the intended locking …

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Waterfall Formation At A Desert River-Reservoir Delta Isolates Endangered Fishes, Charles N. Cathcart, Casey A. Pennock, Christopher A. Cheek, Mark C. Mckinstry, Peter D. Mackinnon, Mary M. Conner, Keith B. Gido Sep 2018

Waterfall Formation At A Desert River-Reservoir Delta Isolates Endangered Fishes, Charles N. Cathcart, Casey A. Pennock, Christopher A. Cheek, Mark C. Mckinstry, Peter D. Mackinnon, Mary M. Conner, Keith B. Gido

Wildland Resources Faculty Publications

Unforeseen interactions of dams and declining water availability have formed new obstacles to recovering endemic and endangered big-river fishes. During a recent trend of drying climate and declining reservoir water levels in the southwestern United States, a large waterfall has formed on two separate occasions (1989-1995 & 2001-present) in the transition zone between the San Juan River and Lake Powell reservoir because of deposited sediments. Because recovery plans for two large-bodied endangered fish species, razorback sucker (Xyrauchen texanus) and Colorado pikeminnow (Ptychocheilus lucius), include annual stockings in the San Juan River, this waterfall potentially blocks upstream …

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Evidence For Subsurface Origin Of Boulder Caves, Roofed Slots And Boulder-Filled Canyons (Broumov Highland, Czechia), Filip Duszyński, Kacper Jancewicz, Piotr Migoń Sep 2018

Evidence For Subsurface Origin Of Boulder Caves, Roofed Slots And Boulder-Filled Canyons (Broumov Highland, Czechia), Filip Duszyński, Kacper Jancewicz, Piotr Migoń

International Journal of Speleology

The backslope of a sandstone cuesta in the Broumov Highland (Czechia) is cut by a complex network of canyons. Long sections of canyons have thick boulder fills which are difficult to reconcile with simple rock fall and talus development scenario. Boulder caves occur within these fills and their lowermost parts are drained by streams that evacuate fine loose sandy material produced by weathering and mechanical erosion. These boulder fills are explained as largely in situ, residual features, left after subsurface selective disintegration of rock mass, mainly joint-guided, and removal of grains by underground water. Evacuation of fines leaves voids …

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Statistical Modeling Of Co2 Flux Data, Fang He Sep 2018

Statistical Modeling Of Co2 Flux Data, Fang He

Electronic Thesis and Dissertation Repository

Carbon dioxide (CO2) flux is important for agriculture and carbon cycle studies. Only a small proportion of the land is currently covered by proper equipment to directly collect CO2 flux data. The CO2 flux data has an obvious annual cycle with the phase changing from year to year. How to build a model to estimate the annual effect and seasonal dynamics is a challenging task. With the help of the Moderate Resolution Imaging Spectroradiometer (MODIS) which is carried by NASA satellites, corresponding data, such as normalized difference vegetation index (NDVI), is freely available from NASA. Our goals are modeling the …

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Parameter Sensitivity For In Vitro Anthrax Studies, Yareley Gonzalez, Maria Macias-Bedolla, Megan O. Powell Sep 2018

Parameter Sensitivity For In Vitro Anthrax Studies, Yareley Gonzalez, Maria Macias-Bedolla, Megan O. Powell

Spora: A Journal of Biomathematics

Studies done on interactions between spores and macrophages done in vitro show inconsistent results based on experimental protocol and inhibit meaningful extrapolation to in vivo. In this study, we perform a sensitivity analysis of a model representing in vitro studies of interactions between anthrax spores and macrophages to help address the effects of these inconsistencies. We perform both local and global analyses using Latin hypercube sampling and partial rank correlation coefficients. Our analysis indicates the amount of intracellular bacteria over time is most sensitive to the killing of intracellular bacteria by the macrophages and replication of the bacteria inside …

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