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Project Renew Worcester, Danni Yue, Amy Zhang, Jing Han, Omid Ashrafi, Yiming Xu 2018 Clark University

Project Renew Worcester, Danni Yue, Amy Zhang, Jing Han, Omid Ashrafi, Yiming Xu

School of Professional Studies

n The client for this capstone project is RENEW Worcester which is a fledgling solar power project whose main goals are to bring renewable energy in the form of solar power into local, primarily low-income communities and are committed to the mission of making the transition off of fossil fuels to clean, renewable power. Based in Worcester, Massachusetts, they are a local chapter of Co-op Power which is a consumer-owned sustainable energy cooperative (co-op) made up of numerous different local chapters all over the New England area as well as the state of New York. The problem that we will ...


The Contribution Of Local And Transport Processes To Phytoplankton Biomass Variability Over Different Timescales In The Upper James River, Virginia, Qubin Qin, Jian Shen 2018 Virginia Institute of Marine Science

The Contribution Of Local And Transport Processes To Phytoplankton Biomass Variability Over Different Timescales In The Upper James River, Virginia, Qubin Qin, Jian Shen

Articles

Although both local processes (photosynthesis, respiration, grazing, and settling), and transport processes (advective transport and diffusive transport) significantly affect local phytoplankton dynamics, it is difficult to separate their contributions and to investigate the relative importance of each process to the local variability of phytoplankton biomass over different timescales. A method of using the transport rate is introduced to quantify the contribution of transport processes. By combining the time-varying transport rate and high-frequency observed chlorophyll a data, we can explicitly examine the impact of local and transport processes on phytoplankton biomass over a range of timescales from hourly to annually. For ...


What’S At Steak? The Political Discourse Of Emissions Intensity And Implications Of Animal Agriculture, Kalyn Simon 2018 The University of San Francisco

What’S At Steak? The Political Discourse Of Emissions Intensity And Implications Of Animal Agriculture, Kalyn Simon

Master's Theses

This thesis analyzes the international discourse of greenhouse gas emissions in relation to livestock production. Specific government ministries, research institutes, and multilateral organizations are framing a new strategy to mitigate emissions by using emissions intensity metrics. Emissions intensity is a ratio comparing emissions produced per unit of animal product as oppose to measuring absolute emissions. This research is acknowledged as a win-win scenario which allows for a reduction of greenhouse gas emissions while continuing production more efficiently. This thesis outlines the emergence of this metric in international discourse and the implications this shift has on the livestock sector globally. Ultimately ...


Three Environmental Fluid Dynamics Papers, Eden Furtak-Cole 2018 Utah State University

Three Environmental Fluid Dynamics Papers, Eden Furtak-Cole

All Graduate Theses and Dissertations

Three papers are presented, applying computational fluid dynamics methods to fluid flows in the geosciences. In the first paper, a numerical method is developed for single phase potential flow in the subsurface. For a class of monotonically advancing flows, the method provides a computational savings as compared to classical methods and can be applied to problems such as forced groundwater recharge. The second paper investigates the shear stress reducing action of an erosion control roughness array. Incompressible Naiver-Stokes simulations are performed for multiple wind angles to understand the changing aerodynamics of individual and grouped roughness elements. In the third paper ...


Emissions Of Organic Compounds From Produced Water Ponds I: Characteristics And Speciation, Seth N. Lyman, Marc L. Mansfield, Huy N.Q. Tran, Jordan D. Evans, Colleen Jones, Trevor O'Neil, Ric Bowers, Ann Smith, Cara Keslar 2018 Utah State University

Emissions Of Organic Compounds From Produced Water Ponds I: Characteristics And Speciation, Seth N. Lyman, Marc L. Mansfield, Huy N.Q. Tran, Jordan D. Evans, Colleen Jones, Trevor O'Neil, Ric Bowers, Ann Smith, Cara Keslar

Chemistry and Biochemistry Faculty Presentations

We measured fluxes of methane, a suite of non-methane hydrocarbons (C2–C11), light alcohols, and carbon dioxide from oil and gas produced water storage and disposal ponds in Utah (Uinta Basin) and Wyoming (Upper Green River Basin) United States during 2013–2016. In this paper, we discuss the characteristics of produced water composition and air-water fluxes, with a focus on flux chamber measurements. In companion papers, we will (1) report on inverse modeling methods used to estimate emissions from produced water ponds, including comparisons with flux chamber measurements, and (2) discuss the development of mass transfer coefficients to estimate emissions ...


Africa's Urban Adaptation Transition Under A 1.5° Climate, Mark Pelling, Hayley Leck, Lorena Pasquini, Idowu Ajibade, Emanuel Osuteye, Susan Parnell, Shuaib Lwasa, Cassidy Johnson, Arabella Fraser, Alejandro Barcena, Soumana Boubacar 2018 King's College London

Africa's Urban Adaptation Transition Under A 1.5° Climate, Mark Pelling, Hayley Leck, Lorena Pasquini, Idowu Ajibade, Emanuel Osuteye, Susan Parnell, Shuaib Lwasa, Cassidy Johnson, Arabella Fraser, Alejandro Barcena, Soumana Boubacar

Geography Faculty Publications and Presentations

Highlights

• Everyday risk associated with inadequate basic infrastructure and poverty make even small natural hazards impactful in African cities.

• Enhanced development opportunity is the best for of risk reduction.

• Integrating risk reduction into development is constrained by donor priorities, fragmented city governance and data and monitoring gaps.

• Integrating risk reduction into development is enabled through community networks collaborating with city authorities, locally accountable leadership and improved risk data and forecasting.


Multivariate Spectral Analysis Of Crism Data To Characterize The Composition Of Mawrth Vallis, Melissa Luna 2018 Wesleyan University

Multivariate Spectral Analysis Of Crism Data To Characterize The Composition Of Mawrth Vallis, Melissa Luna

Melissa Luna

No abstract provided.


A Model Of Competition Between Perpetual Software And Software As A Service, Zhiling GUO, Dan MA 2018 Singapore Management University

A Model Of Competition Between Perpetual Software And Software As A Service, Zhiling Guo, Dan Ma

Research Collection School Of Information Systems

Software as a service (SaaS) has grown to be a significant segment of many software product markets. SaaS vendors, which charge customers based on use and continuously improve the quality of their products, have put competitive pressure on traditional perpetual software vendors, which charge a licensing fee and periodically upgrade the quality of their software. We develop an analytical model to study the competitive pricing strategies of an incumbent perpetual software vendor in the presence of a SaaS competitor. We find that, depending on both the SaaS quality improvement rate and the network effect, the perpetual software vendor adopts one ...


In Operando Mechanism Analysis On Nanocrystalline Silicon Anode Material For Reversible And Ultrafast Sodium Storage, Lei Zhang, Xianluo Hu, Chaoji Chen, Haipeng Guo, Xiaoxiao Liu, Gengzhao Xu, Haijian Zhong, Shuang Cheng, Peng Wu, Jiashen Meng, Yunhui Huang, Shi Xue Dou, Hua-Kun Liu 2018 University of Wollongong

In Operando Mechanism Analysis On Nanocrystalline Silicon Anode Material For Reversible And Ultrafast Sodium Storage, Lei Zhang, Xianluo Hu, Chaoji Chen, Haipeng Guo, Xiaoxiao Liu, Gengzhao Xu, Haijian Zhong, Shuang Cheng, Peng Wu, Jiashen Meng, Yunhui Huang, Shi Xue Dou, Hua-Kun Liu

Australian Institute for Innovative Materials - Papers

Presently, lithium-ion batteries (LIBs) are the most promising commercialized electrochemical energy storage systems. Unfortunately, the limited resource of Li results in increasing cost for its scalable application and a general consciousness of the need to find new type of energy storage technologies. Very recently, substantial effort has been invested to sodium-ion batteries (SIBs) due to their effectively unlimited nature of sodium resources. Furthermore, the potential of Li/Li+ is 0.3 V lower than that of Na/Na+, which makes it more effective to limit the electrolyte degradation on the outer surface of the electrode.[1] Nevertheless, one major obstacle ...


A Model Of Competition Between Perpetual Software And Software As A Service, Zhiling GUO, Dan MA 2018 Singapore Management University

A Model Of Competition Between Perpetual Software And Software As A Service, Zhiling Guo, Dan Ma

Research Collection School Of Information Systems

Software as a service (SaaS) has grown to be a significant segment of many software product markets. SaaS vendors, which charge customers based on use and continuously improve the quality of their products, have put competitive pressure on traditional perpetual software vendors, which charge a licensing fee and periodically upgrade the quality of their software. We develop an analytical model to study the competitive pricing strategies of an incumbent perpetual software vendor in the presence of a SaaS competitor. We find that, depending on both the SaaS quality improvement rate and the network effect, the perpetual software vendor adopts one ...


Studies Of Geometrical Profiling In Fabricated Tapered Optical Fbers Using Whispering Gallery Modes Spectroscopy, Vishnu Kavungal, Gerald Farrell, Qiang Wu, Arun Kumar Mallik, Yuliya Semenova 2018 Dublin Institute of Technology

Studies Of Geometrical Profiling In Fabricated Tapered Optical Fbers Using Whispering Gallery Modes Spectroscopy, Vishnu Kavungal, Gerald Farrell, Qiang Wu, Arun Kumar Mallik, Yuliya Semenova

Articles

This paper experimentally demonstrates a method for geometrical profiling of asymmetries in fabricated thin microfiber tapers with waist diameters ranging from ∼10 to ∼50µm with submicron accuracy. The method is based on the analysis of whispering gallery mode resonances excited in cylindrical fiber resonators as a result of evanescent coupling of light propagating through the fiber taper. The submicron accuracy of the proposed method has been verified by SEM studies. The method can be applied as a quality control tool in fabrication of microfiber based devices and sensors or for fine-tuning of microfiber fabrication set-ups.


The Integer-Magic Spectra And Null Sets Of The Cartesian Product Of Trees, Wai Chee Shiu, Richard M. Low 2018 Hong Kong Baptist University

The Integer-Magic Spectra And Null Sets Of The Cartesian Product Of Trees, Wai Chee Shiu, Richard M. Low

HKBU Staff Publication

No abstract provided.


Infinitely Many Solutions To Asymmetric, Polyharmonic Dirichlet Problems, Edger Sterjo 2018 The Graduate Center, City University of New York

Infinitely Many Solutions To Asymmetric, Polyharmonic Dirichlet Problems, Edger Sterjo

All Dissertations, Theses, and Capstone Projects

In this dissertation we prove new results on the existence of infinitely many solutions to nonlinear partial differential equations that are perturbed from symmetry. Our main theorems focus on polyharmonic Dirichlet problems with exponential nonlinearities, and are now published in Topol. Methods Nonlinear Anal. Vol. 50, No.1, (2017), 27-63. In chapter 1 we give an introduction to the problem, its history, and the perturbation argument itself. In chapter 2 we prove the variational principle of Bolle on the behavior of critical values under perturbation, and the variational principle of Tanaka on the existence of critical points of large augmented ...


Investigation Of Novel Electrolytes For Use In Lithium-Ion Batteries And Direct Methanol Fuel Cells, Kartik Pilar 2018 The Graduate Center, City University of New York

Investigation Of Novel Electrolytes For Use In Lithium-Ion Batteries And Direct Methanol Fuel Cells, Kartik Pilar

All Dissertations, Theses, and Capstone Projects

Energy storage and conversion plays a critical role in the efficient use of available energy and is crucial for the utilization of renewable energy sources. To achieve maximum efficiency of renewable energy sources, improvements to energy storage materials must be developed. In this work, novel electrolytes for secondary batteries and fuel cells have been studied using nuclear magnetic resonance and high pressure x-ray scattering techniques to form a better understanding of dynamic and structural properties of these materials. Ionic liquids have been studied due to their potential as a safer alternative to organic solvent-based electrolytes in lithium-ion batteries and composite ...


Prairie Strips Improve Biodiversity And The Delivery Of Multiple Ecosystem Services From Corn–Soybean Croplands, Lisa A. Schulte, Jarad Niemi, Matthew J. Helmers, Matt Liebman, J. Gordon Arbuckle, David E. James, Randall K. Kolka, Matthew E. O'Neal, Mark D. Tomer, John C. Tyndall, Heidi Asbjornsen, Pauline Drobney, Jeri Neal, Chris Witte 2018 Iowa State University

Prairie Strips Improve Biodiversity And The Delivery Of Multiple Ecosystem Services From Corn–Soybean Croplands, Lisa A. Schulte, Jarad Niemi, Matthew J. Helmers, Matt Liebman, J. Gordon Arbuckle, David E. James, Randall K. Kolka, Matthew E. O'Neal, Mark D. Tomer, John C. Tyndall, Heidi Asbjornsen, Pauline Drobney, Jeri Neal, Chris Witte

Jarad Niemi

Loss of biodiversity and degradation of ecosystem services from agricultural lands remain important challenges in the United States despite decades of spending on natural resource management. To date, conservation investment has emphasized engineering practices or vegetative strategies centered on monocultural plantings of nonnative plants, largely excluding native species from cropland. In a catchment-scale experiment, we quantified the multiple effects of integrating strips of native prairie species amid corn and soybean crops, with prairie strips arranged to arrest run-off on slopes. Replacing 10% of cropland with prairie strips increased biodiversity and ecosystem services with minimal impacts on crop production. Compared with ...


Impacts Of 4r Nitrogen Management On Drainage Water Quality, Matthew J. Helmers 2018 Iowa State University

Impacts Of 4r Nitrogen Management On Drainage Water Quality, Matthew J. Helmers

Matthew J. Helmers

Much of the U.S. Corn Belt is characterized by relative flat, poorly-drained areas which with extensive subsurface drainage, have become some of the most valuable and productive agricultural land in the world. However, this is not without consequences. Nitrate-N loss from these systems is of particular concern due to its potential adverse impacts on both public health and ecosystem function. In addition to the potential local impacts on receiving waters in the Corn Belt, nitrogen loads from the region are suspected as a primary contributor to hypoxia in the Gulf of Mexico. For nearly 30 years Iowa State University ...


Drainage Design For Improved Profits And Water Quality, Matthew J. Helmers, Greg Brenneman 2018 Iowa State University

Drainage Design For Improved Profits And Water Quality, Matthew J. Helmers, Greg Brenneman

Matthew J. Helmers

Subsurface drainage systems are an important component of agricultural production systems in many areas of Iowa. However, these drainage systems have been shown to deliver nitrate-N to downstream waterbodies. So, while subsurface drainage is important for crop production we also need to consider the design of these systems to minimize nitrate-N loss. Use of drainage water management in the design and operation of subsurface drainage systems is one potential method to reduce nitrate-N loss.


Modeling The Impacts Of Climate Change On Nitrogen Losses And Crop Yield In A Subsurface Drained Field, Zhaozhi Wang, Qhiming Qi, Lulin Xue, Melissa Bukovsky, Matthew J. Helmers 2018 McGill University

Modeling The Impacts Of Climate Change On Nitrogen Losses And Crop Yield In A Subsurface Drained Field, Zhaozhi Wang, Qhiming Qi, Lulin Xue, Melissa Bukovsky, Matthew J. Helmers

Matthew J. Helmers

The effect of climate change on crop production and nitrate-nitrogen (NO3-N) pollution from subsurface drained fields is of a great concern. Using the calibrated and validated RZWQM2 (coupled with CERES-Maize and CROPGRO in DSSAT), the potential effects of climate change and elevated atmospheric CO2 concentrations (CO2) on tile drainage volume, NO3-N losses, and crop production were assessed integrally for the first time for a corn-soybean rotation cropping system near Gilmore City, Iowa. RZWQM2 simulated results under 20-year observed historical weather data (1990–2009) and ambient CO2 were compared to those under 20-year projected future meteorological data (2045–2064) and elevated ...


Ionic Depletion At The Crystalline Gibbs Layer Of Peg-Capped Gold Nanoparticle Brushes At Aqueous Surfaces, Wenjie Wang, Honghu Zhang, Surya Mallapragada, Alex Travesset, David Vaknin 2018 Ames Laboratory

Ionic Depletion At The Crystalline Gibbs Layer Of Peg-Capped Gold Nanoparticle Brushes At Aqueous Surfaces, Wenjie Wang, Honghu Zhang, Surya Mallapragada, Alex Travesset, David Vaknin

Surya K. Mallapragada

In situ surface-sensitive x-ray diffraction and grazing incidence x-ray fluorescence spectroscopy (GIXFS) methods are combined to determine the ionic distributions across the liquid/vapor interfaces of thiolated-polyethylene-glycol–capped gold nanoparticle (PEG-AuNP) solutions. Induced by the addition of salts (i.e., Cs2SO4) to PEG-AuNPs solutions, two-dimensional hexagonal lattices of PEG-AuNPs form spontaneously at the aqueous surfaces, as is demonstrated by x-ray reflectivity and grazing incidence small-angle x-ray scattering. By taking advantage of element specificity with the GIXFS method, we find that the cation Cs+ concentration at the crystalline film is significantly reduced in parts of the PEG-AuNP film compared with that ...


Electrical Stimulation For Enhanced Denitrification In Woodchip Bioreactors: Opportunities And Challenges, J. Y. Law, Michelle L. Soupir, D. Raj Raman, T. B. Moorman, Say K. Ong 2018 Iowa State University

Electrical Stimulation For Enhanced Denitrification In Woodchip Bioreactors: Opportunities And Challenges, J. Y. Law, Michelle L. Soupir, D. Raj Raman, T. B. Moorman, Say K. Ong

D. Raj Raman

Woodchip bioreactors are being implemented for the removal of nitrates in groundwater and tile water drainage. However, low nitrate removals in denitrifying woodchip bioreactors have been observed for short hydraulic retention time (HRT) and low water temperature (°C). One potential approach to improve woodchip bioreactor performance is to provide an alternative and readily available electron source to the denitrifying microorganisms through electrical stimulation. Previous work has demonstrated the capability of bio-electrochemical reactors (BER) to remove a variety of water contaminants, including nitrate, in the presence of a soluble carbon source. The objective of this study was to evaluate the denitrification ...


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