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2019

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Articles 781 - 810 of 15927

Full-Text Articles in Physical Sciences and Mathematics

Soil Classification Based On Spectral And Environmental Variables, Andre Carnieletto Dotto, Raphael A. Viscara Rossel, Jose Am Dematte, Rodnei Rizzo Dec 2019

Soil Classification Based On Spectral And Environmental Variables, Andre Carnieletto Dotto, Raphael A. Viscara Rossel, Jose Am Dematte, Rodnei Rizzo

The State of Soil Science in WA

In the last decades, the volume of soil data collection has increased significantly. Because of that it is now possible to obtain a soil classification using spectral, climate and terrain attributes. The idea was to develop a soil series system, which intends to discriminate soil types according to soil, climate and terrain variables. This new system was called Soil-Environmental Classification.


Black Soldier Fly Technology Can Convert Manure Into Valuable Fertiliser, Sasha Jenkins, Zhuoda Huang, Bede Mikan, Morten Andersen, Luke Wheat, Lynette Abbott Dec 2019

Black Soldier Fly Technology Can Convert Manure Into Valuable Fertiliser, Sasha Jenkins, Zhuoda Huang, Bede Mikan, Morten Andersen, Luke Wheat, Lynette Abbott

The State of Soil Science in WA

Black Soldier Fly (Hermetia illucens, BSF) farming provides an alternative low-cost waste management solution for converting agricultural waste into high quality insect meal (BSF larvae as animal feed) and a valuable fertiliser (BSF casting residue or frass).

The aim of this study was to investigate the slow-releasing effect of N after coating the BSF frass with three different fatty acids (lauric, myristic and stearic acid).


Ilime An App For Assessing The Management Of Soil Acidity In Agricultural Systems, James Fisher, Jenni Clausen, Fiona Evans, Chris Gazey Dec 2019

Ilime An App For Assessing The Management Of Soil Acidity In Agricultural Systems, James Fisher, Jenni Clausen, Fiona Evans, Chris Gazey

The State of Soil Science in WA

iLIme mobile app is available for download for Apple and Android devices from your preferred app store.

https://www.agric.wa.gov.au/apps/ilime

Awareness of soil acidity as a constraint to agricultural production in Western Australia has led to increased use of lime, but rates remain too low to manage existing acidic soil and ongoing acidification. To invest in lime, growers need confidence in likely economic and production responses. This paper describes the development of an acidification calculator, in app form, that was developed with input and feedback to ensure that it would meet the needs and requirements of users.


Extending The Message Of Soil Quality In The Mobile Device Era, Chris Gazey, Frances Hoyle Dec 2019

Extending The Message Of Soil Quality In The Mobile Device Era, Chris Gazey, Frances Hoyle

The State of Soil Science in WA

In this day and age, where everyone is time poor, making information easily and quickly available is paramount. However, with a topic as complex and as multi-dimensional as soil quality, a new approach to packaging information that is evidence-based and relevant to the local environment is required. Apple multimedia digital books provide a platform capable of delivering layers of information on mobile devices.


Simulating Australian Soil Organic Carbon Sequestration, Juhwan Lee, Raphael A. Viscarra Rossell Dec 2019

Simulating Australian Soil Organic Carbon Sequestration, Juhwan Lee, Raphael A. Viscarra Rossell

The State of Soil Science in WA

National initiatives to mitigate and adopt to climate change imply the need for enhancing carbon (C) sequestration in soils. Soil process models often render a C baseline hardly representative and its C sequestration potential questionable when initial soil C pools are not accounted. Here we use the soil process model Roth C to simulate site-specific soil C across 4431 sites in Australia. After matching the modelled and measured C pools at initial equilibrium, the model predicted C sequestration potentials in soils, coherent to changes among the pools, in response to soil inputs that represent soil and residue management. We show …


Gravel Is Soil Is Gravel, David Weaver, Ron Master, David Rogers Dec 2019

Gravel Is Soil Is Gravel, David Weaver, Ron Master, David Rogers

The State of Soil Science in WA

Around 3.8 M ha of gravelly soil contributes to crop production in south west WA. Soil analysis and glasshouse experiments routinely take place in the absence of the ≥2 mm fraction. Typical processes include sample collection, air drying, and sieving (<2 mm) prior to experimentation or analysis. The ≥2 mm fraction is discarded as it is often considered inert, acting as a soil volume diluent, and problematic for routine chemical analysis when intact because of size and representativeness. However, the literature cites that the ≥2 mm fraction may contribute positively to soil chemical, physical and biological properties.


Evolution Of Ryegrass Resistance To Glyphosate Changes Soil Microbial Diversity 14 Years Continuous Application, Zakaria Solaiman, Abul Hashem, Bede Mikan, Lynette Abbott, Paul Storer, Vivek Bhat, Andrew Whitely Dec 2019

Evolution Of Ryegrass Resistance To Glyphosate Changes Soil Microbial Diversity 14 Years Continuous Application, Zakaria Solaiman, Abul Hashem, Bede Mikan, Lynette Abbott, Paul Storer, Vivek Bhat, Andrew Whitely

The State of Soil Science in WA

Glyphosate is the most widely used herbicides in agriculture. Short-term impacts of glyphosate on soil microbial communities have been reported but long-term effects are rarely studied. There is concern for non-target effects on soil microbial communities with potential to negatively affect soil functions after long-term use of glyphosate. Therefore, our objective was to investigate changes in bacterial community composition following long-term glyphosate application on annual ryegrass.


Soil Nitrogen Storage And Availability To Crops Are Increased By Conservation Agriculture Practices In Rice-Based Cropping Systems In The Eastern Gangetic Plains, Md. Khairal Alam, Richard Bell, M E. Haque, M A. Islam, M A. Kader Dec 2019

Soil Nitrogen Storage And Availability To Crops Are Increased By Conservation Agriculture Practices In Rice-Based Cropping Systems In The Eastern Gangetic Plains, Md. Khairal Alam, Richard Bell, M E. Haque, M A. Islam, M A. Kader

The State of Soil Science in WA

On-farm adoption of minimum soil disturbance and increased residue retention will alter nitrogen (N) dynamics in soils and N fertiliser management in the intensive rice–based triple cropping systems of the Eastern Gangetic Plains. However, the consequences of changes in N forms, N mineralisation and N availability for crops in these cropping systems have not been determined.


Dynamics Of Water Use By Wheat And Canola Crops In Compacted, Acidic Sands Treated With Deep Tillage And Lime, Gaus Azam, Chris Gazey, Richard Bowles Dec 2019

Dynamics Of Water Use By Wheat And Canola Crops In Compacted, Acidic Sands Treated With Deep Tillage And Lime, Gaus Azam, Chris Gazey, Richard Bowles

The State of Soil Science in WA

Incorporation of agricultural lime by ‘strategic deep tillage’ is one of the quickest methods for managing subsurface soil acidity. Such soil amelioration practice decreases soil resistance by removing compaction and increases soil pH, which allows deep penetration of crop roots, and hence increases the acquisition of soil water from deeper in the soil. As a result of improved soil physical and chemical properties, crop yield also increases and so does the water use efficiency (WUE). Under broadacre cropping conditions, WUE is generally estimated from crop yield and weather data; actual measurement of soil water uptake can lead to more accurate …


Crop Response To Amelioration Of Agricultural Soils Are Mediated By Contraint Combinations And Soil Type, Stephen Davies, Wayne Parker, Giacomo Betti, David Hall, Tom Edwards, Chad Reynolds, Glenn Macdonald Dec 2019

Crop Response To Amelioration Of Agricultural Soils Are Mediated By Contraint Combinations And Soil Type, Stephen Davies, Wayne Parker, Giacomo Betti, David Hall, Tom Edwards, Chad Reynolds, Glenn Macdonald

The State of Soil Science in WA

Over the past decade alternative strategic deep tillage approaches have been developed to complement more established soil amelioration methods. Strategic tillage takes the form of a one-off or occasional intervention, implemented to overcome a number of soil and biotic constraints. Deep ripping can effectively remove subsoil hardpans and potentially delve up some subsoil to the surface depending on tine design. Deep soil mixing, using rotary spaders or large disc ploughs, can mix and incorporate topsoil and amendments deeper into the soil profile and reduce topsoil repellence. Soil inversion, using mouldboard, square or one-way disc ploughs, can bury surface-applied amendments, as …


Subsoil Contraints And Their Management: Overview From Five Years Of R&D, David Hall, Yvette Oliver, Shahab Pathan, Karen Holmes, Dennis Van Gool, Geoff Anderson, Jeremy Lemon, Caroline Peek, Liz Petersen, Glenn Macdonald, E G. Barrett-Lennard, Dana Mulvaney, Glen Riethmuller, Edward Arnold Griffin, Phil Ward Dec 2019

Subsoil Contraints And Their Management: Overview From Five Years Of R&D, David Hall, Yvette Oliver, Shahab Pathan, Karen Holmes, Dennis Van Gool, Geoff Anderson, Jeremy Lemon, Caroline Peek, Liz Petersen, Glenn Macdonald, E G. Barrett-Lennard, Dana Mulvaney, Glen Riethmuller, Edward Arnold Griffin, Phil Ward

The State of Soil Science in WA

Subsoil constraints cost the grains industry more than $1.6b in lost production each year. Diagnosing and mapping subsoil constraints (SSC) was achieved at a shire scale using the DPIRD soils database and historic surveys.


Weather And Climate Summary And Forecast: December 2019 Report, Gregory V. Jones Dec 2019

Weather And Climate Summary And Forecast: December 2019 Report, Gregory V. Jones

Linfield University Wine Studies Reports

This report provides a summary of the weather and climate forecast for December 2019. It includes forecast information specific to the Pacific Northwest and the western United States, as well as forecast information for other portions of the United States and abroad.


Multidisciplinary Observing In The World Ocean's Oxygen Minimum Zone Regions: From Climate To Fish - The Voice Initiative, V Garcon, J Karstensen, A Palacz, Et Al, Kevin C. Weng Dec 2019

Multidisciplinary Observing In The World Ocean's Oxygen Minimum Zone Regions: From Climate To Fish - The Voice Initiative, V Garcon, J Karstensen, A Palacz, Et Al, Kevin C. Weng

VIMS Articles

Multidisciplinary ocean observing activities provide critical ocean information to satisfy ever-changing socioeconomic needs and require coordinated implementation. The upper oxycline (transition between high and low oxygen waters) is fundamentally important for the ecosystem structure and can be a useful proxy for multiple observing objectives connected to eastern boundary systems (EBSs) that neighbor oxygen minimum zones (OMZs). The variability of the oxycline and its impact on the ecosystem (VOICE) initiative demonstrates how societal benefits drive the need for integration and optimization of biological, biogeochemical, and physical components of regional ocean observing related to EBS. In liaison with the Global Ocean Oxygen …


Growth And Characterization Of Organic Ferroelectric And Magnetic Thin Films, Xuanyuan Jiang Dec 2019

Growth And Characterization Of Organic Ferroelectric And Magnetic Thin Films, Xuanyuan Jiang

Department of Physics and Astronomy: Dissertations, Theses, and Student Research

Compared to inorganic materials, organic materials are environmentally friendly, flexible, and often with low cost. Inspired by these advantages, organic materials-based electronics have been intensively studied for comparable or better functionalities to inorganic electronics.

This dissertation mainly focuses on the growth and characterizations of organic ferroelectrics and magnetic thin films. For organic ferroelectrics, we investigate the growth and ferroelectric measurements of thin film croconic acid (CA), a proton-transfer molecular ferroelectric (FE) material with a large spontaneous polarization and a small coercive field, as well as the origin of ferroelectricity in CA in terms of the photostriction effect, including the discovery …


College Of Engineering Senior Design Competition Fall 2019, University Of Nevada, Las Vegas Dec 2019

College Of Engineering Senior Design Competition Fall 2019, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Part of every UNLV engineering student’s academic experience, the senior design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. A capstone to the student’s educational career, the senior design project encourages the student to use everything learned in the engineering program to create a practical, real world solution to an engineering challenge. The senior design competition helps focus the senior students in increasing the quality and potential for commercial application for their design projects. Judges from local industry evaluate the projects on …


Determination Of Global Mean Eddy Diffusive Transport In The Mesosphere And Lower Thermosphere From Atomic Oxygen And Carbon Dioxide Climatologies, G. R. Swenson, C. C. J. H. Salinas, F. Vargas, Y. Zhu, M. Kaufmann, M. Jones Jr., A. Liu, Et Al. Dec 2019

Determination Of Global Mean Eddy Diffusive Transport In The Mesosphere And Lower Thermosphere From Atomic Oxygen And Carbon Dioxide Climatologies, G. R. Swenson, C. C. J. H. Salinas, F. Vargas, Y. Zhu, M. Kaufmann, M. Jones Jr., A. Liu, Et Al.

Publications

Quantifying the eddy diffusion coefficient profile in the mesosphere and lower thermosphere (MLT) is critical to the constituent density distributions in the upper mesosphere and thermosphere. Previous work by Swenson et al. (2018, https://doi.org/10.1016/j.jastp.2018.05.014) estimated the global mean eddy diffusion (kzz) values in the upper mesosphere using atomic oxygen (O), derived from Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) hydroxyl (OH). In this study, vertical eddy diffusive transport velocities of O were determined from continuity of mass in the mesopause region (80–97 km), primarily via the HOx chemistry. Global average constituent climatology from previously deduced SABER ozone (O3) …


Composition Effect On The Carrier Dynamics And Catalytic Performance Of Cuins2/Zns Quantum Dots For Light Driven Hydrogen Generation, Wenhui Hu, Sizhuo Yang, Jier Huang Dec 2019

Composition Effect On The Carrier Dynamics And Catalytic Performance Of Cuins2/Zns Quantum Dots For Light Driven Hydrogen Generation, Wenhui Hu, Sizhuo Yang, Jier Huang

Chemistry Faculty Research and Publications

Water soluble CuInS2/ZnS quantum dots (QDs) represent one of the most promising single component photocatalysts for the hydrogen evolution reaction (HER). In this work, we report the effect of cation composition in CuInS2/ZnS QDs on the carrier relaxation and charge separation dynamics as well as their photocatalytic performance for the HER. With decreasing Cu to In ratio (increasing Cu deficiency), we observed slightly faster electron trapping and carrier recombination but significantly improved photocatalytic activity for the HER. This can be attributed to the enhanced electron transfer (ET) from the sacrificial donor to CuInS2/ZnS QDs …


Quantum-Enhanced Advanced Ligo Detectors In The Era Of Gravitational-Wave Astronomy, M. Tse, Haocun Yu, N. Kijbunchoo, A. Fernandez-Galiana, P. Dupej, L. Barsotti, C. D. Blair, D. D. Brown, S. E. Dwyer, Karla E. Ramirez Dec 2019

Quantum-Enhanced Advanced Ligo Detectors In The Era Of Gravitational-Wave Astronomy, M. Tse, Haocun Yu, N. Kijbunchoo, A. Fernandez-Galiana, P. Dupej, L. Barsotti, C. D. Blair, D. D. Brown, S. E. Dwyer, Karla E. Ramirez

Physics and Astronomy Faculty Publications and Presentations

The Laser Interferometer Gravitational Wave Observatory (LIGO) has been directly detecting gravitational waves from compact binary mergers since 2015. We report on the first use of squeezed vacuum states in the direct measurement of gravitational waves with the Advanced LIGO H1 and L1 detectors. This achievement is the culmination of decades of research to implement squeezed states in gravitational-wave detectors. During the ongoing O3 observation run, squeezed states are improving the sensitivity of the LIGO interferometers to signals above 50 Hz by up to 3 dB, thereby increasing the expected detection rate by 40% (H1) and 50% (L1).


Recent Experimental Findings Supporting Smarandache’S Hypothesis And Quantum Sorites Paradoxes And Subquantum Kinetic Model Of Electron, Victor Christianto, Robert N. Boyd, Florentin Smarandache Dec 2019

Recent Experimental Findings Supporting Smarandache’S Hypothesis And Quantum Sorites Paradoxes And Subquantum Kinetic Model Of Electron, Victor Christianto, Robert N. Boyd, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

Smarandache Hypothesis states that there is no speed limit of anything, including light and particles. While the idea is quite simple and based on known hypothesis of quantum mechanics, called Einstein-Podolski-Rosen paradox, in reality such a superluminal physics seems still hard to accept by majority of physicists. Here we review some experiments to support superluminal physics and also findings to explain Smarandache Quantum Paradoxes and Quantum Sorites Paradox. We also touch briefly on new experiment on magneton, supporting SubQuantum Kinetic Model of Electron.

Conclusion & Significance: Multiexperimental findings assessment allows one to verify conjectures by two of us (FS & …


Re-Reading Wilczek’S Remark On “Lost In Math”: The Perils Of Postempirical Science And Their Resolution, Victor Christianto, Florentin Smarandache Dec 2019

Re-Reading Wilczek’S Remark On “Lost In Math”: The Perils Of Postempirical Science And Their Resolution, Victor Christianto, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

Sabine Hossenfelder’s recent book “Lost in Math” has attracted numerous responses, including by notable physicists such as Frank Wilczek. In this article we focus on Wilczek’s remark on that book, in particular on the perils of postempirical science. We also discuss shortly multiverse hypothesis from philosophical perspective. In last section, we offer a resolution from the perspective of Neutrosophic Logic on this problem of classical tension between mathematics and experience approach to physics, which seems to cause the stagnation of modern physics.


Exploring The Relationship Between Vocabulary Scaling And Algorithmic Performance In Text Classification For Large Datasets, Wilson Murray Fearn Dec 2019

Exploring The Relationship Between Vocabulary Scaling And Algorithmic Performance In Text Classification For Large Datasets, Wilson Murray Fearn

Theses and Dissertations

Text analysis is a significant branch of natural language processing, and includes manydifferent sub-fields such as topic modeling, document classification, and sentiment analysis.Unsurprisingly, those who do text analysis are concerned with the runtime of their algorithmsSome of these algorithms have runtimes that depend jointly on the size of the corpus beinganalyzed, as well as the size of that corpus's vocabulary. Trivially, a user may reduce theamount of data they feed into their model to speed it up, but we assume that users will behesitant to do this as more data tends to lead to better model quality. On the other …


Temporally Consistent Urban-Rural Delineations For Global Urban Heat Island Monitoring, Tc Chakraborty Dec 2019

Temporally Consistent Urban-Rural Delineations For Global Urban Heat Island Monitoring, Tc Chakraborty

Yale Day of Data

Urbanization leads to local-scale modification of climate, particularly the urban heat island (UHI) effect - the high temperature in cities compared to their surroundings. The UHI effect is generally quantified by measuring the temperature differential between the city and its surrounding rural reference. Choices of both the city and the rural reference are prone to assumptions, which may affect, among other things, temporal variability in UHI intensity. To reduce these uncertainties, I create a global dataset of urban-rural delineations that can be used to better constrain the temporal trends in UHI intensity throughout the globe using the European Space Agency's …


Generating Contextual Text Embeddings For Emergency Department Chief Complaints Using Bert, David Chang Dec 2019

Generating Contextual Text Embeddings For Emergency Department Chief Complaints Using Bert, David Chang

Yale Day of Data

We applied BERT, a state-of-the-art natural language processing model, on chief complaint data from the Yale Emergency Department to map free-text notes to structured chief complaint categories.


Saving Software And Using Emulation To Reproduce Computationally Dependent Research Results, Euan Cochrane, Limor Peer, Ethan Gates, Seth Anderson Dec 2019

Saving Software And Using Emulation To Reproduce Computationally Dependent Research Results, Euan Cochrane, Limor Peer, Ethan Gates, Seth Anderson

Yale Day of Data

Using digital data necessarily involves software. How do institutions think about software in the context of the long-term usability of their data assets? How do they address usability challenges uniquely posed by software such as, license restrictions, legacy software, code rot, and dependencies? These questions are germane to the agenda set forth by the FAIR principles. At Yale University, a team in the Library is looking into the application of a novel approach to emulation as a potential solution. In this presentation, we will outline the work of the Emulation as a Service Infrastructure (EaaSI) program, discuss our plans for …


A New Method To Solve Same-Different Problems With Few-Shot Learning, Yuanyuan Han Dec 2019

A New Method To Solve Same-Different Problems With Few-Shot Learning, Yuanyuan Han

Electronic Thesis and Dissertation Repository

Visual learning of highly abstract concepts is often simple for humans but very challenging for machines. Same-different (SD) problems are a visual reasoning task with highly abstract concepts. Previous work has shown that SD problems are difficult to solve with standard deep learning algorithms, especially in the few-shot case, despite the ability of such algorithms to learn abstract features. In this thesis, we propose a new method to solve SD problems with few training samples, in which same-different visual concepts can be recognized by examining similarities between Regions of Interest by using a same-different twins network. Our method achieves state-of-the-art …


Barrier Layer Impact On Rapid Intensification Of Hurricanes (2000-2018) In The Atlantic Ocean, J. Gaston Hayworth Dec 2019

Barrier Layer Impact On Rapid Intensification Of Hurricanes (2000-2018) In The Atlantic Ocean, J. Gaston Hayworth

HCNSO Student Capstones

Hurricane prediction is an evolving challenge that has seen much improvement over the years. While hurricane models have improved in predicting the path of storms, forecasts of hurricane intensity are unreliable due to the complexity of environmental data, lack of understanding of how relative humidity, vertical wind shear, hurricane structure and other possible factors affect intensity. Rapid Intensification (RI), which is a wind speed increase of +30 kts over a 24-hr period, can contribute to major destruction and loss of life to coastal communities affected by hurricanes, and is especially difficult to predict. Given the continued development of coastal regions …


Crustal Structure Beneath The East Coast Magnetic Anomaly From Seismic Refraction Tomography, Collin C. Brandl Dec 2019

Crustal Structure Beneath The East Coast Magnetic Anomaly From Seismic Refraction Tomography, Collin C. Brandl

Earth and Planetary Sciences ETDs

Syn-rift igneous addition is necessary for successful continental breakup. Past investigations of passive margins have focused on strike perpendicular structure, but potential field anomalies indicate that significant crustal variations may be present. Data from 21 ocean bottom seismometers was acquired as part of the Eastern North American Margin Community Seismic Experiment and was used for tomographic inversion to create 2D velocity models of the margin that are representative of crustal structure. Crustal thickness varies along-strike from ~20 km to ~24 km and a high velocity (Vp > 7 km/s) layer is present at the base of the crust above the Moho. …


Static Taint Analysis Of Binary Executables Using Architecture-Neutral Intermediate Representation, Elaine Cole Dec 2019

Static Taint Analysis Of Binary Executables Using Architecture-Neutral Intermediate Representation, Elaine Cole

All Computer Science and Engineering Research

Ghidra, National Security Agency’s powerful reverse engineering framework, was recently released open-source in April 2019 and is capable of lifting instructions from a wide variety of processor architectures into its own register transfer language called p-code. In this project, we present a new tool which leverages Ghidra’s specific architecture-neutral intermediate representation to construct a control flow graph modeling all program executions of a given binary and apply static taint analysis. This technique is capable of identifying the information flow of malicious input from untrusted sources that may interact with key sinks or parts of the system without needing access to …


Rain Gardens: The Return Of Ecosystem Services, Katie Dehaan Dec 2019

Rain Gardens: The Return Of Ecosystem Services, Katie Dehaan

Honors Theses

In the modern world impervious surfaces, especially in urban areas, abound. These include roads, highways, sidewalks, parking lots, and roofs that have replaced permeable surfaces, mainly open land, forests, and wetlands. Rainwater runs off of these surfaces collecting pollutants on its way to permeable areas. Rain gardens collect and process rainwater. Native plants with deep root systems process large volumes of rainwater and the microorganisms living in the soils and roots can process pollutants. The purpose of my research was to find out what variables affect species presence or absence in rain gardens. Species presence or absence at the time …


Air Quality And Environmental Justice: An Analysis Of County-Level Data In The United States, Alyssa Tittle Dec 2019

Air Quality And Environmental Justice: An Analysis Of County-Level Data In The United States, Alyssa Tittle

Honors Theses

This paper analyzes the relationship between air pollution and poverty and race/ethnicity at the county level in the United States. Using air pollution data from the Environmental Protection Agency and population characteristics data from the Census Bureau to model relationships in RStudio, results show that race/ethnicity, population, and median value of owner-occupied housing units are the most statistically significant variables associated with air quality.