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The Effects Of Black Locust (Robinia Pseudoacacia L.) On Understory Vegetation And Soils In A Northern Hardwood Forest, Keri A. Deneau

Dissertations, Master's Theses and Master's Reports - Open

No abstract provided.

Sustainable Energy Production In The United States: Life Cycle Assessment Of Biofuels And Bioenergy, Jiqing Fan

Dissertations, Master's Theses and Master's Reports - Open

The United States of America is making great efforts to transform the renewable and abundant biomass resources into cost-competitive, high-performance biofuels, bioproducts, and biopower. This is the key to increase domestic production of transportation fuels and renewable energy, and reduce greenhouse gas and other pollutant emissions.

This dissertation focuses specifically on assessing the life cycle environmental impacts of biofuels and bioenergy produced from renewable feedstocks, such as lignocellulosic biomass, renewable oils and fats. The first part of the dissertation presents the life cycle greenhouse gas (GHG) emissions and energy demands of renewable diesel (RD) and hydroprocessed jet fuels (HRJ). The …

Production Of Recombinant Trichoderma Reesei Endoglucanase Protein Cel7b By Using Kluyveromyces Lactis, Zainab Ibrahim Alshoug

Dissertations, Master's Theses and Master's Reports - Open

This research is about producing recombinant Trichoderma reesei endoglucanase Cel7B by using Kluyveromyces lactis, transformed with chromosomally integrated Cel7B cDNA, as a host cell (K. lactis Cel7B). Cel7B is one of the glycoside hydrolyze family of proteins that are produced by T. reesei. Cel7B together with other endoglucanases, exoglucanases, and â-glucosidases hydrolyze cellulose to glucose, which can then be fermented to biofuels or other value-added products.

The research objective of this MS project is to examine favorable fermentation conditions for recombinant Cel7B enzyme production and improved activity. Production of enzyme on different types of media was examined, and the activity …

Plant-Mediated Effects On Microbial Diversity In Mesocosms Of An Oligotrophic Bog, Karl J. Romanowicz Iv

Dissertations, Master's Theses and Master's Reports - Open

Globally, peatlands occupy a small portion of terrestrial land area but contain up to one-third of all soil organic carbon. This carbon pool is vulnerable to increased decomposition under projected climate change scenarios but little is known about how plant functional groups will influence microbial communities responsible for regulating carbon cycling processes. Here we examined initial shifts in microbial community structure within two sampling depths under plant functional group manipulations in mesocosms of an oligotrophic bog. Microbial community composition for bacteria and archaea was characterized using targeted 16S rRNA Illumina gene sequencing. We found statistically distinct spatial patterns between the …

Magneto-Photonic Crystals For Optical Sensing Applications, Neluka Dissanayake

Dissertations, Master's Theses and Master's Reports - Open

Among the optical structures investigated for optical sensing purpose, a significant amount of research has been conducted on photonic crystal based sensors. A particular advantage of photonic crystal based sensors is that they show superior sensitivity for ultra-small volume sensing. In this study we investigate polarization changes in response to the changes in the cover index of magneto-optic active photonic band gap structures. One-dimensional photonic-band gap structures fabricated on iron garnet materials yield large polarization rotations at the band gap edges. The enhanced polarization effects serve as an excellent tool for chemical sensing showing high degree of sensitivity for photonic …

A Novel Approach To Carbon Dioxide Capture And Storage, Brett P. Spigarelli

Dissertations, Master's Theses and Master's Reports - Open

The novel approach to carbon capture and storage (CCS) described in this dissertation is a significant departure from the conventional approach to CCS. The novel approach uses a sodium carbonate solution to first capture CO₂ from post combustion flue gas streams. The captured CO₂ is then reacted with an alkaline industrial waste material, at ambient conditions, to regenerate the carbonate solution and permanently store the CO₂ in the form of an added value carbonate mineral. Conventional CCS makes use of a hazardous amine solution for CO₂ capture, a costly thermal regeneration stage, and the underground storage …

Evaluation Of Sugar Maple Dieback In The Upper Great Lakes Region And Development Of A Forest Health Youth Education Program, Tara L. Bal

Dissertations, Master's Theses and Master's Reports - Open

Acer saccharum Marsh., is one of the most valuable trees in the northern hardwood forests. Severe dieback was recently reported by area foresters in the western Upper Great Lakes Region. Sugar Maple has had a history of dieback over the last 100 years throughout its range and different variables have been identified as being the predisposing and inciting factors in different regions at different times. Some of the most common factors attributed to previous maple dieback episodes were insect defoliation outbreaks, inadequate precipitation, poor soils, atmospheric deposition, fungal pathogens, poor management, or a combination of these. The current sugar maple …

Security Evaluation Of Substation Network Architectures, Pingal Raj Sapkota

Dissertations, Master's Theses and Master's Reports - Open

In recent years, security of industrial control systems has been the main research focus due to the potential cyber-attacks that can impact the physical operations. As a result of these risks, there has been an urgent need to establish a stronger security protection against these threats. Conventional firewalls with stateful rules can be implemented in the critical cyberinfrastructure environment which might require constant updates. Despite the ongoing effort to maintain the rules, the protection mechanism does not restrict malicious data flows and it poses the greater risk of potential intrusion occurrence.

The contributions of this thesis are motivated by the …

Influence Of Mechanical And Thermal Boundary Conditions On Stabilizing/Destabilizing Mechanisms In Evaporating Liquid Films, Aneet Dharmavaram Narendranath

Dissertations, Master's Theses and Master's Reports - Open

Liquid films, evaporating or non-evaporating, are ubiquitous in nature and technology. The dynamics of evaporating liquid films is a study applicable in several industries such as water recovery, heat exchangers, crystal growth, drug design etc. The theory describing the dynamics of liquid films crosses several fields such as engineering, mathematics, material science, biophysics and volcanology to name a few.

Interfacial instabilities typically manifest by the undulation of an interface from a presumed flat state or by the onset of a secondary flow state from a primary quiescent state or both. To study the instabilities affecting liquid films, an evaporating/non-evaporating Newtonian …

A Cost-Benefit Analysis Of A 25% Rps In Michigan, Fei Li

Dissertations, Master's Theses and Master's Reports - Open

Michigan depends heavily on fossil fuels to generate electricity. Compared with fossil fuels, electricity generation from renewable energy produces less pollutants emissions. A Renewable Portfolio Standard (RPS) is a mandate that requires electric utilities to generate a certain amount of electricity from renewable energy sources. This thesis applies the Cost-Benefits Analysis (CBA) method to investigate the impacts of implementing a 25% in Michigan by 2025. It is found that a 25% RPS will create about $20.12 billion in net benefits to the State. Moreover, if current tax credit policies will not change until 2025, its net present value will increase …

Study Of Spark Ignition Engine Combustion Model For The Analysis Of Cyclic Variation And Combustion Stability At Lean Operating Conditions, Hao Wu

Dissertations, Master's Theses and Master's Reports - Open

A fundamental combustion model for spark-ignition engine is studied in this report. The model is implemented in SIMULINK to simulate engine outputs (mass fraction burn and in-cylinder pressure) under various engine operation conditions. The combustion model includes a turbulent propagation and eddy burning processes based on literature [1]. The turbulence propagation and eddy burning processes are simulated by zero-dimensional method and the flame is assumed as sphere. To predict pressure, temperature and other in-cylinder variables, a two-zone thermodynamic model is used. The predicted results of this model match well with the engine test data under various engine speeds, loads, spark …

Effective Function Choice In The R Scripting Language, Trevor D. Fisher

Dissertations, Master's Theses and Master's Reports - Open

This project examines the current available work on the explicit and implicit parallelization of the R scripting language and reports on experimental findings for the development of a model for predicting effective points for automatic parallelization to be performed, based upon input data sizes and function complexity. After finding or creating a series of custom benchmarks, an interval based on data size and time complexity where replacement becomes a viable option was found; specifically between O(N) and O(N³) exclusive. As data size increases, the benefits of parallel processing become more apparent and a point is reached where those …

Evaluation And Monitoring Of Ash (Fraxinus Spp.) Tolerant To Long-Term Emerald Ash Borer (Agrilus Planipennis [Coleoptera: Buprestidae]) Exposure, Kathryn G. Hietala

Dissertations, Master's Theses and Master's Reports - Open

Invasive insects that successfully establish in introduced areas can significantly alter natural communities. These pests require specific establishment criteria (e.g. host suitability) that, when known, can help quantify potential damage to infested areas. Emerald ash borer (Agrilus planipennis [Coleoptera: Buprestidae]) is an invasive phloem-feeding pest which is responsible for the death of millions of ash trees (Fraxinus spp. L.). Over 200 surviving ash trees were previously identified in the Huron-Clinton Metroparks located in southeast Michigan. Trees were assessed over a four year period and a hierarchical cluster analysis was performed on dieback, vigor, and presence of signs and …

The Problematic Of Privacy In The Namespace, Randal Sean Harrison

Dissertations, Master's Theses and Master's Reports - Open

In the twenty-first century, the issue of privacy--particularly the privacy of individuals with regard to their personal information and effects--has become highly contested terrain, producing a crisis that affects both national and global social formations. This crisis, or problematic, characterizes a particular historical conjuncture I term the namespace. Using cultural studies and the theory of articulation, I map the emergent ways that the namespace articulates economic, juridical, political, cultural, and technological forces, materials, practices and protocols. The cohesive articulation of the namespace requires that privacy be reframed in ways that make its diminution seem natural and inevitable. In the popular …

The Effects Of Web-Based Technological Resources In A Rural Science Classroom, Joseph D. Heflin

Dissertations, Master's Theses and Master's Reports - Open

Today’s technology is evolving at an exponential rate. Everyday technology is finding more inroads into our education system. This study seeks to determine if having access to technology, including iPad tablets and a teacher's physical science webpage resources (videos, PowerPoint® presentations, and audio podcasts), assists ninth grade high school students in attaining greater comprehension and improved scientific literacy.

Comprehension of the science concepts was measured by comparing current student pretest and post test scores on a teacher-written assessment. The current student post test scores were compared with prior classes’ (2010-2011 and 2009-2010) to determine if there was a difference in …

Technology, Transportation, And Scale In The Koyokuk Placer Mining District 1890s - 1930s, Jessica Sarah Peterson

Dissertations, Master's Theses and Master's Reports - Open

The Koyukuk Mining District was one of several northern, turn of the century, gold rush regions. Miners focused their efforts in this region on the Middle Fork of the Koyukuk River and on several of its tributaries. Mining in the Koyukuk began in the 1880s and the first rush occurred in 1898. Continued mining throughout the early decades of the 1900s has resulted in an historic mining landscape consisting of structures, equipment, mining shafts, waste rock, trash scatters, and prospect pits. Modern work continues in the region alongside these historic resources. An archaeological survey was completed in 2012 as part …

Migration Patterns Among Young Adults In The United States: Environmental, Social, And Economic Explanations, Fangming Liu

Dissertations, Master's Theses and Master's Reports - Open

Young adult migration is a key factor in community development. The goal of this paper is to study what kinds of places attract young adults and what kinds are losing them. Linear regression is conducted to analyze what place-specific factors explain migration patterns among young adults. These factors include economic, social, and environmental variables. This study finds that social and environmental factors are just as important as economic ones. Specifically, employment in the arts increases young adult net migration. Environmental variables, for example, natural amenities and protected federal lands are particularly important in rural settings in attracting young adults. These …

The Processing Of Aluminum Gasarites Via Thermal Decomposition Of Interstitial Hydrides, Joseph James Licavoli

Dissertations, Master's Theses and Master's Reports - Open

Gasarite structures are a unique type of metallic foam containing tubular pores. The original methods for their production limited them to laboratory study despite appealing foam properties. Thermal decomposition processing of gasarites holds the potential to increase the application of gasarite foams in engineering design by removing several barriers to their industrial scale production. The following study characterized thermal decomposition gasarite processing both experimentally and theoretically. It was found that significant variation was inherent to this process therefore several modifications were necessary to produce gasarites using this method. Conventional means to increase porosity and enhance pore morphology were studied. Pore …

Investigations Of Cloud Microphysical Response To Mixing Using Digital Holography, Matthew Jacob Beals

Dissertations, Master's Theses and Master's Reports - Open

Cloud edge mixing plays an important role in the life cycle and development of clouds. Entrainment of subsaturated air affects the cloud at the microscale, altering the number density and size distribution of its droplets. The resulting effect is determined by two timescales: the time required for the mixing event to complete, and the time required for the droplets to adjust to their new environment. If mixing is rapid, evaporation of droplets is uniform and said to be homogeneous in nature. In contrast, slow mixing (compared to the adjustment timescale) results in the droplets adjusting to the transient state of …

Computational Prediction Of The Sporulation Network In Clostridium Thermocellum, Changyi Jiang

Dissertations, Master's Theses and Master's Reports - Open

Sporulation is a process in which some bacteria divide asymmetrically to form tough protective endospores, which help them to survive in a hazardous environment for a quite long time. The factors which can trigger this process are diverse. Heat, radiation, chemicals and lacking of nutrition can all lead to the formation of endospores. This phenomenon will lead to low productivity during industrial production. However, the sporulation mechanism in a spore-forming bacterium, Clostridium theromcellum, is still unclear. Therefore, if a regulation network of sporulation can be built, we may figure out ways to inhibit this process. In this study, a …

Pesky Pests Of The Great Lakes State: Is Public Participation Influenced By Geographic Differences?, Angela Yu

Dissertations, Master's Theses and Master's Reports - Open

In Michigan, environmental issues, such as invasive species, are not geographically constrained, affecting citizens throughout the state. Regulations and management plans organized by scientists and officials are intended to address issues statewide, but these policies may not adequately tackle the threat from invasive species as it impacts different parts of the state at different times. Participation and contributions from citizens can offer insight into the impacts and changes non-native species have on the local ecosystem. However, chances to participate and contribute may be influenced by geographic location in the state. To understand if this was the case, this research studied …

The Planned And The Emergent: An Alternative Model Of Learning And Literacy, Lori S. Rogers

Dissertations, Master's Theses and Master's Reports - Open

Within academic institutions, writing centers are uniquely situated, socially rich sites for exploring learning and literacy. I examine the work of the Michigan Tech Writing Center's UN 1002 World Cultures study teams primarily because student participants and Writing Center coaches are actively engaged in structuring their own learning and meaning-making processes. My research reveals that learning is closely linked to identity formation and leading the teams is an important component of the coaches' educational experiences. I argue that supporting this type of learning requires an expanded understanding of literacy and significant changes to how learning environments are conceptualized and developed. …

The Holographic Detector For Clouds From Trl 5 To Trl 8, Matthew Jacob Beals

Dissertations, Master's Theses and Master's Reports - Open

Clouds are one of the most influential elements of weather on the earth system, yet they are also one of the least understood. Understanding their composition and behavior at small scales is critical to understanding and predicting larger scale feedbacks. Currently, the best method to study clouds on the microscale is through airborne in situ measurements using optical instruments capable of resolving clouds on the individual particle level. However, current instruments are unable to sufficiently resolve the scales important to cloud evolution and behavior. The Holodec is a new generation of optical cloud instrument which uses digital inline holography to …

Development Of The Ecocar 3 Proposal And Guidelines For Modeling And Design In Year One Of Ecocar 3, Tyler B. Daavettila

Dissertations, Master's Theses and Master's Reports - Open

This report summarizes the work done for the Vehicle Powertrain Modeling and Design Problem Proposal portion of the EcoCAR3 proposal as specified in the Request for Proposal from Argonne National Laboratory.

The results of the modeling exercises presented in the proposal showed that:

• An average conventional vehicle powered by a combustion engine could not meet the energy consumption target when the engine was sized to meet the acceleration target, due the relatively low thermal efficiency of the spark ignition engine.
  

• A battery electric vehicle could not meet the required range target of 320 km while keeping the vehicle weight below …

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Breaking Codes: Making Theories On Menstruation Accessible Through Third-Wave Feminism, Carole S. Reynolds

Dissertations, Master's Theses and Master's Reports - Open

Men and women respond to situations according to their community’s social codes. With menstruation, people adhere to “menstrual codes”. Within academic communities, people adhere to “academic codes”. This report paper investigates performances of academic codes and menstrual codes. Implications of gender identity and race are missing and/or minimal in past feminist work regarding menstruation. This paper includes considerations for gender identity and race. Within the examination of academic codes, this paper discusses the inhibitive process of idea creation within the academic sphere, and the limitations to the predominant ways of knowledge sharing within, and outside of, the academic community. The …

Teaching The Gas Properties And Gas Laws: An Inquiry Unit With Alternative Assessment, Michael Hammar

Dissertations, Master's Theses and Master's Reports - Open

As a chemistry teacher I felt that the gas laws were rather simple concepts to understand. My students, however, felt the opposite. Conceptual issues, as well as mathematical issues were problematic every year. In this study, a unit about gas properties and gas laws was modified to include inquiry-based teaching methods. The research questions focused on how these changes affected student results on a traditional end-of-the-unit test and on an alternative assessment. Students’ attitudes during these lessons were also monitored to see if the inquiry methods improved student perceptions of teaching, learning, and self-awareness. The results of this study showed …

Lattice Boltzmann Method And Cellular Automata Simulation Of Particle Motion And Deposition In 2-D Case, Yichao Deng

Dissertations, Master's Theses and Master's Reports - Open

This technical report discusses the application of the Lattice Boltzmann Method (LBM) and Cellular Automata (CA) simulation in fluid flow and particle deposition. The current work focuses on incompressible flow simulation passing cylinders, in which we incorporate the LBM D2Q9 and CA techniques to simulate the fluid flow and particle loading respectively. For the LBM part, the theories of boundary conditions are studied and verified using the Poiseuille flow test. For the CA part, several models regarding simulation of particles are explained. And a new Digital Differential Analyzer (DDA) algorithm is introduced to simulate particle motion in the Boolean model. …

A Comparative Study Of Heuristic Optimization Algorithms, Rohit A. Bhatia

Dissertations, Master's Theses and Master's Reports - Open

Heuristic optimization algorithms are of great importance for reaching solutions to various real world problems. These algorithms have a wide range of applications such as cost reduction, artificial intelligence, and medicine. By the term cost, one could imply that that cost is associated with, for instance, the value of a function of several independent variables. Often, when dealing with engineering problems, we want to minimize the value of a function in order to achieve an optimum, or to maximize another parameter which increases with a decrease in the cost (the value of this function). The heuristic cost reduction algorithms work …

Spring Discharge Monitoring In Low-Resource Settings: A Case Study Of Concepción Chiquirichapa, Guatemala, Stephanie C. Tubman

Dissertations, Master's Theses and Master's Reports - Open

Water springs are the principal source of water for many localities in Central America, including the municipality of Concepción Chiquirichapa in the Western Highlands of Guatemala. Long-term monitoring records are critical for informed water management as well as resource forecasting, though data are scarce and monitoring in low-resource settings presents special challenges. Spring discharge was monitored monthly in six municipal springs during the author’s Peace Corps assignment, from May 2011 to March 2012, and water level height was monitored in two spring boxes over the same time period using automated water-level loggers. The intention of this approach was to circumvent …

A Comparison Of Pixel-Based Versus Object Oriented Analysis Of Landslides Using Historical Remote Sensing Data, Ren N. Keyport

Dissertations, Master's Theses and Master's Reports - Open

With recent advances in remote sensing processing technology, it has become more feasible to begin analysis of the enormous historic archive of remotely sensed data. This historical data provides valuable information on a wide variety of topics which can influence the lives of millions of people if processed correctly and in a timely manner. One such field of benefit is that of landslide mapping and inventory. This data provides a historical reference to those who live near high risk areas so future disasters may be avoided. In order to properly map landslides remotely, an optimum method must first be determined. …