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The renewable energy of the wood pellet market has taken great attention over the last few periods. However, the returns from the pellet business depend largely on how well the quality of biomass. The objective is to economically harvest pellets matching pellet standards set forward by the U.S. markets. The single-mindedness of this study is to develop a Bayesian network model to ensure a high-quality flow through the supply chain of the pallet industry in the top ten counties in Mississippi state. Multiple critical decisions (harvesting, storage, transportation, and quality control) of a biomass-to-pellet supply system could potentially affect the supply chain. The biomass-to pellet supply chain is an extremely challenging problem. For Multi-criteria Decision Making,we have developed criteria and sub-criteria associated with biomass-to pellet supply chain pellet. Experimental results specify that the biomass-to-pellet stream system is complex to the biomass quality parameters especially ash and moisture contents. Fifty were studied and ten locations were recommended and ranked based on affordability and resiliency of the availability of both corn stover and forest residues in the depot facilities. There are several anticipated and unpredicted energy turbulence in the Depots property. Pellets have been recognized as an alternative power approach to managing risk throughout power generation. These prospective users from using alternative power. This research proposes a solid foundation for in-depth future research to acquire detailed insights into how the Pellets depots location works in practice in Mississippi state to give a more substantial basis for strategic, tactical, and operational levels of possible risk profiles in Mississippi state.

The study was performed at Billerudkorsnäs at the section Box Lab which offers knowledge and solutions for packaging. Paper that can be used to create packaging interacts with the surrounding environment, but has only been tested for a few climates. This thesis aims to investigate more climates and see how paper is affected by humidity and temperature and try to determine the cause of the results. The methods used to measure this was primary tensile test and moisture content analysis but also a test to evaluate creep was performed in climates with high humidity. From this, the mechanical properties of the paper were calculated. The test was performed in a climate chamber and the choice of methods was limited by what could be performed in the climate chamber. The materials tested were chosen to give a good representation of what is commonly used in the containerboard business. The climates for testing were selected from the ability of the climate chamber as well as interesting climates for the company. The results show that the papers are weakest at high RH, but the results indicate that the temperature solely impacts the properties of the paper. The highest moisture content does not necessarily mean the lowest value for a chosen property. The causes for the results are not clear since the patterns found are not bound to a certain quality but rather to paper in general. Therefore, more research on the area is suggested to try to determine what causes the material to react to temperature.

Oats are considered to be a highly nutritious breakfast food available to consumers. Heightened consumer interest in functional food products and advances in human nutrition have led to increased levels of interest in the development of new oat based products (Webster and Wood 2011). Developments in technology have led to manufacturing of instant oatmeal, making the product more convenient to consumers. Low moisture extrusion processing is one of the most widely used methods to produce ready to eat breakfast cereals; however, there has been little research carried out to determine if high moisture extrusion methods would be viable. This study evaluated the economic and technical feasibility to utilize high moisture extrusion processing to produce ready to eat oatmeal. A process economics evaluation included measuring the capital requirements to implement the system, process costing to estimate the weighted average unit cost, and net present value of high moisture extrusion production. The capital expense was significantly high. However, the unit cost is comparable to similar products in the market. The net present value of implementing the technology revealed a significant profit over the course of 20 years. Six different technical experiments were performed using a twin screw extruder, each experiment testing for the effect of different extrusion variables on finished product texture. Reference texture data was measured using a control product currently made in the industry using an alternative batch process. The processing parameters which seemed to have the biggest influence on product quality were high rates of water injection, low feed rate, high reaction zone temperature, reduction of particle size, and the use of functional ingredients in the formula. Technical hurdles such as low dwell times, steam plugging, and inconsistent feeding prevented complete starch gelatinization and the steady state of extrusion. Overall, the high moisture methodology did not yield product quality that was consistent and cannot be recommended for use.

Moisture damage in asphalt pavement has always been a problem for drivers, bicyclists, and pedestrians. The primary objective of this study is to evaluate moisture susceptibility of Hot-Mix Asphalt (HMA) and to investigate mitigation techniques using different antistripping agents. Three types of antistripping agents were used in this research investigation. Two of which are chemical based and the other is hydrated lime. The two types of liquid antistripping agents used in this study include Arr Maz CC LOF-6500 and Arr Maz CC XL-9000. These two liquid antistripping agents were tested at 0.25%, 0.50%, and 0.75%. Hydrated Lime was tested at 1.0%, 1.5%, and 2.0%. The binder used in this study is Asphalt Performance Grade (PG) 64-16 provided by Oxnard Refinery. The crushed stone aggregate used in this study was provided by Cal Portland. This study follows the guidelines of standardized AASHTO, ASTM, and SuperPave mix design for all preparation and test procedures. A total of 120 4-inch by 2.83-inch core specimens with void ratios between 6 to 8 percent were created to test for moisture susceptibility in accordance with the Modified Lottman Test, which tested for Indirect Tensile Strength and Immersion Compression Test, which tested for Compression Strength and Elasticity. During the test, half of these specimens were placed in a hot water bath for 24 hours to condition the sample to represent field performance and the other half were unconditioned. Based on the results, the best liquid antistripping agent is XL-9000 at 0.50% and hydrated lime is most efficient at a dosage rate of 1.5%. The best performing antistripping additive for the value is hydrated lime at 1.5%.

Large public events, such as concerts, rallies, and festivals, impact turf health when held on natural turfgrass surfaces. The impact associated with these events is due to the placement of physical structures such as stages and seating areas and pedestrian and vehicular traffic on the turf surface. Trafficked turf protection covers, which are field covers meant to be placed directly on the turf surface where pedestrian or vehicular traffic is expected and/or equipment will be placed, can be used to minimize damage to the turf surface. Scientific data on turf response to these covers is lacking. Four cover treatments comprised of a non-covered non-trafficked control, plywood, plywood + Enkamat Plus, and white high-density polypropylene [single sided (Terratile) or double sided (Matrax)] were applied to tall fescue (Festuca arundinacea Schreb.) and effects of light intensity, duration of covering, season and soil moisture were evaluated. Growth chambers and field experiments were conducted in 2010-2011. Tissue samples were taken in growth chambers experiments every four days over the 20-day period to analyze chlorophyll (Chl a, Chl b, Chl a+b) and carotenoids (carot) under split factors of light intensity (12hr, PAR 530 μmol m-2 s-1, 5 μmol m-2 s-1) and soil moisture (50%, 75% of pot soil moisture capacity). Field trial treatment effects were observed every two days and eight days after cover removal in the spring, summer and fall and a normalized difference vegetative index (NDVI) measure was used at the conclusion of each trial period to confirm visual ratings. Covers that allowed light transmission to the canopy provided the best visual retention of percent green cover and higher contents of Chl a, Chl b, Chl a+b and carot. However, when treatments were tested under conditions that simulated low light under a concert stage (PAR 5 μmol m-2 s-1), covers performed similarly. Moderate soil moisture increased Chl b and carot content under covers. Field trials showed that plywood and plywood + Enkamat allowed for acceptable covering periods of six days in spring, four days in fall, and zero days in summer. Summer conditions shortened the number of days (8 -10) thattall fescue could be covered with Matrax and Terratile and still maintain an acceptable level of green cover. Matrax performed the best during high temperatures and did not tend to sink into the turf in saturated soil. All covers exhibited desirable qualities and limitations that should be considered for turf protection during an event. / Master of Science

Humidity responsive materials sense, respond and adapt to the environment in response to changes in humidity. An important potential application of this material technology is the creation of “smart textiles” that facilitate moisture management in clothing. Materials used for clothing must have characteristics such as elasticity, washability and abrasion resistance, but smart textiles that have been demonstrated to date lack these characteristics. It is the need for improved materials that motivated the present study. Here, we developed spore-cellulose nanofiber composites (CNF) and spore-polyurethane (PU) composites, which are two biologically-based humidity-responsive materials that derive their high energy density humidity responsiveness from spores. We demonstrate the use of these hygromorphing materials for smart textiles by coupling the responsive materials to fabrics to create a textile that vents in humid environments and closes in dry environments. This material can be used in clothing to enable fast evaporation of sweat from the skin and improved comfort. Because the spore-CNF composite is not elastic stretchy or water resistant and therefore is undesirable for real world clothing applications, we also developed a stretchy spore-PU composite that is simultaneously humidity responsive, stretchy and water and abrasion resistant. In addition, we fabricated spore-PU based hygromorphing fabric bilayer actuators to create venting smart textiles with adaptive permeability properties that are compatible with clothing applications. These smart fabrics have the potential to improve the functionality and utility of garments, especially those intended for athleticwear, workwear and protective garments.

This thesis estimates the ecosystem evaporation response to two forms of aridity: (1) atmospheric aridity in the form of vapor pressure deficit (Chapter 2), and (2) soil moisture aridity (Chapter 4). We also develop new methods to estimate the ecosystem response to aridity. For the response to atmospheric aridity (Chapter 2), we build a theoretical framework that allows us to derive an analytical expression for the ecosystem evaporation response to vapor pressure deficit with all environmental conditions held fixed (Chapter 2). For the response to soil moisture aridity, we develop a method to estimate the response of evaporation to interventions on soil moisture using only passive data generated in a simulated reality (Chapter 4). To guide the development of this data-driven approach, we review and analyze causal inference’s applications in the Earth system, considering generic scenarios that are applicable to the land-atmosphere system as well as many other subdomains of the Earth system (Chapter 3). The subsections below elaborate more on the contents of each Chapter. Chapter 2: When does vapor pressure deficit drive or reduce evaporation? Increasingvapor pressure deficit increases atmospheric demand for water. While increased evaporation in response to increased atmospheric demand seems intuitive, plants are capable of reducing evaporation in response to increased vapor pressure deficit by closing their stomata. We examine which effect dominates the response to increasing vapor pressure deficit: atmospheric demand and increases in evaporation, or plant response (stomata closure) and decreases in evaporation. We use Penman-Monteith, combined with semi-empirical optimal stomatal regulation theory and underlying water use efficiency, to develop a theoretical framework for assessing evaporation response to vapor pressure deficit. The theory suggests that depending on the environment and plant characteristics, evaporation response to increasing vapor pressure deficit can vary from strongly decreasing to increasing, highlighting the diversity of plant water regulation strategies. The evaporation response varies due to: 1) climate, with tropical and temperate climates more likely to exhibit a positive evaporation response to increasing vapor pressure deficit than boreal and arctic climates; 2) photosynthesis strategy, with C3 plants more likely to exhibit a positive evaporation response than C4 plants; and 3) plant type, with crops more likely to exhibit a positive evaporation response, and shrubs and gymniosperm trees more likely to exhibit a negative evaporation response. These results, derived from previous literature connecting plant parameters to plant and climate characteristics, highlight the utility of our simplified framework for understanding complex land atmosphere systems in terms of idealized scenarios in which evaporation responds to vapor pressure deficit only. This response is otherwise challenging to assess in an environment where many processes co-evolve together. Chapter 3: Causal inference for process understanding in Earth sciences There is growinginterest in the study of causal methods in the Earth sciences. However, most applications have focused on causal discovery, i.e. inferring the causal relationships and causal structure from data. This paper instead examines causality through the lens of causal inference and how expert-defined causal graphs, a fundamental from causal theory, can be used to clarify assumptions, identify tractable problems, and aid interpretation of results and their causality in Earth science research. We apply causal theory to generic graphs of the Earth system to identify where causal inference may be most tractable and useful to address problems in Earth science, and avoid potentially incorrect conclusions. Specifically, causal inference may be useful when: (1) the effect of interest is only causally affected by the observed portion of the state space; or: (2) the cause of interest can be assumed to be independent of the evolution of the system’s state; or: (3) the state space of the system is reconstructable from lagged observations of the system. However, we also highlight through examples that causal graphs can be used to explicitly define and communicate assumptions and hypotheses, and help to structure analyses, even if causal inference is ultimately challenging given the data availability, limitations and uncertainties. Chapter 4: Estimating the ecosystem evaporation response to interventions on soilmoisture: confounding and causal modeling in a simulated world We build a simulated reality using a numerical model designed to represent feedbacks in the land atmosphere system, and observational boundary conditions that are confounded by the real world’s underlying climate state. Although no simulation can reproduce the real land-atmosphere system’s complexity and any simulation’s predictions will deviate from the real world, this simulated reality does share the same characteristics of the real world that make causal inference challenging: it contains feedbacks, non-linearity, and the real world’s confounding-induced covariations between boundary conditions. We use this simulated reality to estimate confounding’s impact on relationships between soil moisture and ecosystem evaporation, and also to validate a method for calculating ecosystem evaporation response to interventions on soil moisture from passive observations. We repeat this analysis at 12 sites spanning a range of humid and arid climates in western North American and Europe, and find that: • Confounding bias is largest at the more humid sites, and lower at the more arid sites where soil moisture limits evaporation and decouples the response from other environmental factors (Section 4.3.1). • At the more humid sites, bias due to confounding is of a larger magnitude than model specification bias, even when the specified model is a linear model applied to a known non-linear process. This highlights the importance of accounting for confounding. (Section4.3.1). • Statistically adjusting for potential sources of confounding improves causal estimates at the highly confounded sites without degrading causal estimates at arid, soil moisture-limited sites characterized by less confounding bias (Section 4.3.2). • The estimated causal effects appear to differentiate true variations in the causal effects across climates and ecosystems. (Section 4.3.2).

<p> Evaporation was calculated for a subarctic beach ridge, near Churchill, Manitoba, using the energy balance approach. Energy balance calculations for the measurement season revealed an average Bowen ratio, β, of 0.68, with a value of 1.00 representing α' (the evaporability parameter). Fifty-seven percent of the net radiation was utilized by the evaporative heat flux over this tundra surface. Regressions were used to determine the most likely combination of environmental variables responsible for the behaviour of evaporation. Surface soil moisture remained relatively constant throughout the summer measurement period and soil temperatures appeared to be unrelated to evaporation. Air temperature proved to be insignificant to the evaporation flux, and net radiation alone could only account for 54% of the variability. The combination of the net radiation and the wet and dry bulb temperature depression at 1 m accounted for 88% of the variability of the evaoorative heat flux. The mean α' for a site is assumed to be controlled by the surface type in simplified variations of the combination model. The conclusion has been drawn from this study that the variability of α' can be accounted for by variable atmospheric humidities as well as net radiation. The importance of this atmospheric control on the rate of evaporation is emphasized.</p> / Thesis / Master of Science (MSc)