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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 ...


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 ...


A Survey To Better Understand The Use Of The Terms “Colluvium” And “Alluvium”, Bradley A. Miller, Jérôme Juilleret 2018 Iowa State University

A Survey To Better Understand The Use Of The Terms “Colluvium” And “Alluvium”, Bradley A. Miller, Jérôme Juilleret

Bradley A. Miller

We need your help to fully understand how scientists from different backgrounds define the terms “colluvium” and “alluvium.” We ask that you contribute your perspective by taking the survey at http://goo.gl/forms/fV8RBWKjis. The closing deadline is October 31, 2016. The feedback so far has been positive, and many participants have described the experience as fun. Many commented on how the survey challenged their thinking about these sediments, causing them to more carefully consider potential gaps in their definitions for the terms and their strategies for identifying the materials. Others have expressed great interest in the results because ...


An Optical Method For Carbon Dioxide Isotopes And Mole Fractions In Small Gas Samples: Tracing Microbial Respiration From Soil, Litter, And Lignin, Steven J. Hall, Wenjuan Huang, Kenneth E. Hammel 2018 Iowa State University

An Optical Method For Carbon Dioxide Isotopes And Mole Fractions In Small Gas Samples: Tracing Microbial Respiration From Soil, Litter, And Lignin, Steven J. Hall, Wenjuan Huang, Kenneth E. Hammel

Steven J. Hall

Rationale

Carbon dioxide isotope (δ13C value) measurements enable quantification of the sources of soil microbial respiration, thus informing ecosystem C dynamics. Tunable diode lasers (TDLs) can precisely measure CO2 isotopes at low cost and high throughput, but are seldom used for small samples (≤5 mL). We developed a TDL method for CO2 mole fraction ([CO2]) and δ13C analysis of soil microcosms.

Methods

Peaks in infrared absorbance following constant volume sample injection to a carrier were used to independently measure [12CO2] and [13CO2] for subsequent calculation of δ13C values. Using parallel soil incubations receiving differing C substrates, we partitioned respiration from ...


Elevated Moisture Stimulates Carbon Loss From Mineral Soils By Releasing Protected Organic Matter, Wenjuan Huang, Steven J. Hall 2018 Iowa State University

Elevated Moisture Stimulates Carbon Loss From Mineral Soils By Releasing Protected Organic Matter, Wenjuan Huang, Steven J. Hall

Steven J. Hall

Moisture response functions for soil microbial carbon (C) mineralization remain a critical uncertainty for predicting ecosystem-climate feedbacks. Theory and models posit that C mineralization declines under elevated moisture and associated anaerobic conditions, leading to soil C accumulation. Yet, iron (Fe) reduction potentially releases protected C, providing an under-appreciated mechanism for C destabilization under elevated moisture. Here we incubate Mollisols from ecosystems under C3/C4 plant rotations at moisture levels at and above field capacity over 5 months. Increased moisture and anaerobiosis initially suppress soil C mineralization, consistent with theory. However, after 25 days, elevated moisture stimulates cumulative gaseous C-loss as ...


Temporal Statistical Analysis Of Urban Heat Islands At The Microclimate Level, Pui Yun, Paulina WONG, Poh Chin LAI, Melissa HART 2018 University of Hong Kong

Temporal Statistical Analysis Of Urban Heat Islands At The Microclimate Level, Pui Yun, Paulina Wong, Poh Chin Lai, Melissa Hart

Prof. WONG, Pui Yun, Paulina

Urban Heat Islands (UHI) represent the air temperature difference between urban and rural areas. This study deployed a network of miniature sensors to capture road-side microclimate data in both summer and winter. Temporal variations indicated UHI were evident for all time scales, with daily highest and lowest UHI at around midnight and noon/early afternoon respectively. Meteorological and environmental factors influencing UHI were also statistically analyzed by automatic linear regression models. Regression results suggested solar radiation and greenery density were the most important factors with a negative association with UHI intensities in both seasons.


Experiments With The Gravitational Constant, Vildyan Yanbikov 2018 Yanbikov Vildyan Shavkyatovich

Experiments With The Gravitational Constant, Vildyan Yanbikov

Vildyan Yanbikov

Описание эксперимента определяющий зависимость гравитационной постоянной массы, центра тяжести и расстояние до этого центра


Modeling Mayfly Nymph Length Distribution And Population Dynamics Across A Gradient Of Stream Temperatures And Stream Types, Jeremy Anthony, Jennifer Baccam, Imanuel Bier, Emily Gregg, Leif Halverson, Ryan Mulcahy, Emmanuel Okanla, Samira A. Osman, Adam R. Pancoast, Kevin C. Schultz, Alex Sushko, Jennifer Vorarath, Yia Vue, Austin Wagner, Emily Gaenzle Schilling, John M. Zobitz 2018 Augsburg College

Modeling Mayfly Nymph Length Distribution And Population Dynamics Across A Gradient Of Stream Temperatures And Stream Types, Jeremy Anthony, Jennifer Baccam, Imanuel Bier, Emily Gregg, Leif Halverson, Ryan Mulcahy, Emmanuel Okanla, Samira A. Osman, Adam R. Pancoast, Kevin C. Schultz, Alex Sushko, Jennifer Vorarath, Yia Vue, Austin Wagner, Emily Gaenzle Schilling, John M. Zobitz

Spora: A Journal of Biomathematics

We analyze a process-based temperature model for the length distribution and population over time of mayfly nymphs. Model parameters are estimated using a Markov Chain Monte Carlo parameter estimation method utilizing length distribution data at five different stream sites. Two different models (a standard exponential model and a modified Weibull model) of mayfly mortality are evaluated, where in both cases mayfly length growth is a function of stream temperature. Based on model-data comparisons to the modeled length distribution and the Bayesian Information Criterion, we found that approaches that length distribution data can reliably estimate 2–3 model parameters. Future model ...


Use Of Bioadvantaged Materials For Use In Bituminous Modification, Conglin Chen, Joseph H. Podolsky, Nacú B. Hernández, Austin Hohmann, R. Christopher Williams, Eric W. Cochran 2018 Iowa State University

Use Of Bioadvantaged Materials For Use In Bituminous Modification, Conglin Chen, Joseph H. Podolsky, Nacú B. Hernández, Austin Hohmann, R. Christopher Williams, Eric W. Cochran

Eric W. Cochran

Historically, the use of “green” materials around the world has been limited due to their higher production costs when compared to petrochemical derived materials. However, due to the recent volatility and increasing price of petroleum derivatives, there is a growing demand for the use of environmentally friendly materials. One of the most commonly used materials for bitumen modification are poly(styrene-block-butadiene-block-styrene) (SBS) type polymers. Recently, Iowa State University Chemical Engineering Department was able to synthetize thermoplastic elastomers using acrylated epoxidized soybean oil (AESO), a bioadvantaged replacement of butadiene, and styrene with the use of controlled radical polymerization techniques. Initial rheological ...


Superelasticity And Cryogenic Linear Shape Memory Effects Of Cafe2as2, John T. Sypek, Hang Yu, Keith J. Dusoe, Gil Drachuck, Hetal Patel, Amanda M. Giroux, Alan I. Goldman, Andreas Kreyssig, Paul C. Canfield, Serguei L. Bud’ko, Christopher R. Weinberger, Seok-Woo Lee 2018 University of Connecticut

Superelasticity And Cryogenic Linear Shape Memory Effects Of Cafe2as2, John T. Sypek, Hang Yu, Keith J. Dusoe, Gil Drachuck, Hetal Patel, Amanda M. Giroux, Alan I. Goldman, Andreas Kreyssig, Paul C. Canfield, Serguei L. Bud’Ko, Christopher R. Weinberger, Seok-Woo Lee

Paul C. Canfield

Shape memory materials have the ability to recover their original shape after a significant amount of deformation when they are subjected to certain stimuli, for instance, heat or magnetic fields. However, their performance is often limited by the energetics and geometry of the martensitic-austenitic phase transformation. Here, we report a unique shape memory behavior in CaFe2As2, which exhibits superelasticity with over 13% recoverable strain, over 3 GPa yield strength, repeatable stress–strain response even at the micrometer scale, and cryogenic linear shape memory effects near 50 K. These properties are acheived through a reversible uni-axial phase transformation mechanism, the tetragonal ...


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