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On May 7, 2010, a letter signed by 255 members of the US National Academy of Sciences deplored attacks on both science and scientists who researched climate science or related fields. The assaults in the letter rely on two main components. First, statements contradict the preponderance of scientific evidence without a comparable body of evidence to the contrary. Second, as the size of the Intergovernmental Panel on Climate Change (IPCC) reports grows, so does the probability of minor errors. Scientists and their organization should not have to spend the majority of their time defending their work, instead of working on their primary mission of conducting scientific research.

Provides a basic understanding of the principles of solar energy systems, including uses, limitations, material selection, and design practices. Reprinted Originally published February 1979

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The point absorber is one of the most popular types of ocean wave energy converter (WEC) that harvests energy from the ocean. Often such a WEC is deployed in an ocean location with tidal currents or ocean streams, or serves as a mobile platform to power the blue economy. The shape of the floating body, or buoy, of the point absorber type WEC is important for the wave energy capture ratio and for the current drag force. In this work, a new approach to optimize the shape of the point absorber buoy is developed to reduce the ocean current drag force on the buoy while capturing more energy from ocean waves. A specific parametric modeling is constructed to define the shape of the buoy with 12 parameters. The implementation of neural networks significantly reduces the computational time compared to solving hydrodynamics equations for each iteration. And the optimal shape of the buoy is solved using a genetic algorithm with multiple self-defined functions. The final optimal shape of the buoy in a case study reduces 68.7% of current drag force compared to a cylinder-shaped buoy, while maintaining the same level of energy capture ratio from ocean waves. The method presented in this work has the capability to define and optimize a complex buoy shape, and solve for a multi-objective optimization problem. Master of Science The marine kinetic energy includes ocean waves power, tidal power, ocean current power, ocean thermal power and river power. The total potential marine kinetic energy in 2021 is 2300 TWh/year, where 1400 TWh/year is from the ocean wave power. To discover and harvest the huge potential power from the marine, researchers have been developed for different types of WECs for several decades. One of the most successful concepts is the point absorber typed WEC, which can extract waver energy from the heaving vibration motion of a floating body and convert the kinetic energy into electrical energy. This thesis presents an optimization strategy to optimize the shape of the floating body to improve power extraction and reduce the installation cost by implementing the machine learning tool and genetic algorithm. Compared with the state-of-the-art optimization strategies, the proposed optimization method allows the floating body to have more parameters in shape changes and reduces the computational cost from minutes to milliseconds. The final optimized floating body shape performs extraordinarily compared to the other two state-of-the-art floating body shapes.

Spanning 14 states in the northeast United States, the Appalachian Trail (AT) is a popular destination for outdoor recreation, with thousands of individuals attempting to thru-hike the AT every year. For its scenic views and accessibility from the cities, the AT is experiencing a record number of visitors raising concerns about the sustainability of the trail. Many trail organizations manage the AT to reduce the visitor impact on the outdoors. In this research, I study the role of information and communication technologies in promoting collaboration between these trail agencies and visitors. I identify the need for a formal communication channel between the stakeholders by examining the existing information-sharing practices of hikers and trail managers through social media analysis, interviews, and a design workshop. I present the design of an online discussion platform, the SmarTrail board, and conduct a field usability study with two AT trail clubs to evaluate the platform. Findings from the study reveal that centralized direct communication and streamlined information can support trail management on the AT by promoting collaboration within the trail community. The research paves the path for future research into the design of ICTs for driving nature conservation goals. Master of Science The Appalachian Trail (AT) in the northeast of the United States spreads across 14 states. It is accessible from many regional urban centers, offering recreational opportunities to thousands of individuals every year. It is also a popular site for thru-hiking, an endeavor to hike the trail from end to end in a year. Such popularity and accessibility to the trail put pressure on the natural resources, raising concerns about the sustainability of the trail. Management of the trail deals with minimizing the resource impact while preserving the trail experiences of the visitors. Thirty trail clubs maintain separate sections of the AT, and a number of trail organizations work together to manage the trail. The core of this management relies on the collaboration of these trail agencies with each other and the visitors. As communication is central to collaborations in everyday life and for the trail, I explore the practices and possibilities for information sharing and communication on the AT. Digital conservation refers to the technological developments that support and forward nature conservation goals. As the pristine environment of the trails and the AT are not barred from the reach of digital technology, the prevalence of smartphones among visitors presents opportunities for information and communication technologies (ICTs) to support the digital conservation of the trail. In this research, I study digital technology use among hikers and trail managers on the AT, particularly for information sharing. By analyzing comments on Reddit, conducting interviews with the AT trail managers, and organizing a workshop with long-distance hikers, I highlight the need for direct communication between these stakeholders. I present the design of an online discussion board called the SmarTrail platform as a formal communication channel between hikers and trail managers and evaluate it with two trail clubs on the AT. The results from the evaluation offer several use cases of mediated communication, highlighting its need and potential in supporting trail management on the AT. Centralized and formal communication can lead to effective trail management by engaging visitors in trail management, improving volunteer management for the clubs, and enabling knowledge sharing and coordination between the trail agencies. With design considerations for improving human-nature interaction and simplifying the available information for visitors and trail management authorities, this study informs the design of ICTs for trail environments that would forward the digital conservation goals on the AT.

Ni-rich layered oxide materials have gained significant attention due to the ongoing advances and demands in energy storage. The energy revolution continues to catapult the need for improved battery materials, especially for applications in portable electronic devices and electric vehicles. Lithium batteries are at the frontier of energy storage. Due to geopolitical concerns, there is a growing need to understand the chemistries of Co-free, Ni-rich layered oxide materials which are cost-efficient and possess increased practical capacity. The challenge to studying this class of materials is their inherent electronic and structural fragility. The fragility of these materials is facilitated by a cooperation of metal cation migration, lattice oxygen loss, and undesirable oxide cathode-electrolyte interfacial reactions. Each of these phenomena contribute to complex electrolyte decomposition pathways and oxide cathode structural distortions. Structural instability leads to poor battery performance metrics including specific capacity fading and decreased Coulombic efficiency. Electrolyte decomposition occurs at the oxide cathode surface, but it can lead to bulk electronic and structural changes, chemomechanical breakdown, and irreversible phase transformations in the material. The work in this dissertation focuses on understanding some of the chemistries associated with degradation of representative Ni-rich layered oxides, specifically LiNiO2 (LNO) and LiNixMnyCozO2 (NMC) (where x+y+z =1) materials. Chapter 1 provides a comprehensive review of the interfacial chemistries of fragile, Ni-rich layered oxide materials with carbonate-based liquid electrolytes. These reactions are key in deducing mechanistic pathways that promote thermal runaway. Uncontrollable oxygen loss and electrolyte oxidation leads to catastrophic battery fires and explosions. The chapter highlights the material properties that become perturbed during high states-of-charge which complicate the materials chemistry associated with Ni-rich layered oxides. Lastly, a few strategies to mitigate undesired, structurally detrimental reactions at the Ni-rich layered oxide cathode surface are provided in Chapter 1. To obtain the technical data detailed in this dissertation, a variety of analytical methods are employed. Chapter 2 introduces the working principles of the X-ray techniques, electron microscopy, and other quantification methods. X-ray techniques including synchrotron X-ray absorption spectroscopy (XAS), and its components XANES and EXAFS are discussed. Other X-ray techniques, including X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) are additionally included. Electron microscopy techniques, including transmission electron microscopy (TEM), scanning electron microscopy (SEM), and scanning transmission electron microscopy (STEM) are provided. Quantification methods, such as gas chromatography – flame ionization detection (GC-FID) and other electrochemical testing methods are also described. Detailed experimental information obtained using the analytical methods is provided in the technical chapters. In understanding the chemistry of Ni-rich layered oxides, exploring surface reconstruction is key. Surface reconstruction, a phenomenon caused by a collaboration between Li/Ni cation intermixing and lattice oxygen loss, is one of the major explanations for structural degradation in Ni-rich layered oxide materials. Chapter 3 explores surface reconstruction and deduces a mechanism by which lattice oxygen is loss in LiNi0.6Mn0.2Co0.2O2 (NMC622). By exploiting Li+ intercalation chemistry, the work emulates various states-of-charge to explore how delithiation impacts small, organic molecule oxidation. Benzyl alcohol serves as a good probing molecule. It is similar to an oxidizable, nonaqueous electrolytic species that undergoes oxidation at the oxide cathode surface. Structure-reactivity trends are defined to correlate electronic and structural changes, lattice oxygen loss, and small molecule oxidation. After studying a proxy molecule, a practical system is required to grasp the complexity of the cathode-electrolyte interfacial reactions that promote Ni-rich layered oxide degradation. In Chapter 4, an electrolyte stirring experiment is described. Stirring experiments provide an accelerated testing method which helps to deduce the influences of chemical electrolyte decomposition on structural degradation of LiNiO2 (LNO). X-ray techniques are used to illustrate electronic perturbations and structural distortions in the material after probing with EC/DMC w/w 3:7 LiPF6. Additionally, this dissertation chapter features a novel voltage oscillation experiment that is employed to quantify Ni-rich oxide cathode degradation at the phase transition regions. LNO has three charging plateaus – H1 ïƒ M, M ïƒ H2, and H2 ïƒ H3. The latter two plateaus have been largely associated with irreversible structural fragility in Ni-rich layered oxides. Cation intermixing and oxygen loss are two phenomena that are largely associated with decreased Li+ intercalation kinetics and increased undesired side reactions. Although researchers debate the chemical phenomenon that occur at each of the phase transitions, most agree that the H2 ïƒ H3 transition is highly influenced by irreversible lattice oxygen loss. This dissertation chapter describes the studies used to explore the electronic changes and structural distortions that accompany the voltage oscillation electrochemical testing. While Ni-rich layered oxides are largely employed as lithium battery cathodes, this class of material is unique in that it is a reducible and electronically tunable. Electronically modifiable metal oxide materials provide a unique platform to lend information to other applications, such as catalysis. There is much debate surrounding the role of metal oxides on metal nanocatalyst performance for catalytically reductive pathways. Chapter 5 discusses the method of employing LiNiO2 and other NMC materials as electronically tunable metal oxides to determine the role of the reducible metal oxide support on the gold (Au) nanocatalyst for p-nitrophenol reduction to p-aminophenol. By obtaining a continuum of nickel (Ni) oxidation states using delithiation strategies, structural-activity relationship trends are provided. Conversion rates for each of the delithiated materials was calculated using pseudo first-order kinetics. Lastly, a detailed discussion on metal oxide reducibility and its influences on key mechanistic factors, such as the induction period is included. Chapter 6 in this dissertation provides conclusions for the technical work provided. It bridges the works together and describes the overarching findings associated with the chemistries of Ni-rich layered oxide materials. This dissertation lays the foundation for future experimentation and innovation in understanding the surface chemistry of Ni-rich layered oxides. Chapter 7 provides future perspectives for each of the technical works included herein. Additionally, the final chapter includes insights toward the future of lithium batteries and other cathode chemistries. As the world navigates the energy revolution, it is important to provide global perspectives expected to catapult a sustainable future with batteries towards a greener world. Doctor of Philosophy Rechargeable lithium batteries have gained a significant surge of interest due to the ongoing demands for portable electronic devices, as well as the global trend towards electric vehicles to decrease the carbon footprint. Lithium batteries reside at the pinnacle of the energy transition. Layered oxide materials are typically employed as the cathode in Li-ion batteries. Ni-rich layered oxides have gained much interest due to their low cost and good charge/discharge capabilities. As consumers want increased charging rates and longer lifetimes, researchers struggle to optimize the balance between incorporating Ni-rich cathodes and increased safety concerns caused by cathode structural fragility. The lack of structural robustness is largely due to the surface reactivity of Ni-rich layered oxide materials. Bonding arrangements and electron transfer pathways intrinsic to this class of material increases the complexity in understanding the surface chemistry and the associated degradation pathways. Oxygen loss is the major cause of the safety issues in lithium batteries such as battery fires and explosions. To mitigate the safety concerns, it is imperative to understand the chemistries that promote organic, liquid electrolyte decomposition, electronic and structural changes, chemomechanical breakdown, and irreversible phase transformations. Each of these components leads to decreased battery performance. The work in this dissertation describes model and practical platforms to probe and understand the chemistries associated with battery performance degradation. A variety of analytical methods were utilized to determine overall structure-activity relationship trends and are highlighted in Chapter 2. Chapters 3-5 is technical research providing insight on Ni-rich layered oxide degradation pathways and behaviors. The work advances the understanding of battery surface chemistry which will lead to improved cathode design. As batteries continue to grow, it is important to know other applications that benefit from the unique chemistry of Ni-rich layered oxide materials. By exploiting the lithium battery cathode chemistry, this dissertation highlights a method to utilize these materials to understand the role of metal oxides on Au nanocatalysts. Conclusions to the findings in this dissertation are provided in Chapter 6. Future perspectives on the technical research provided herein this dissertation is included in Chapter 7. Additionally, Chapter 7 details future perspectives for lithium batteries and how they can facilitate the global transition toward a sustainable future.

Survivability is by no means a new concept to ocean engineering; ships must remain stable and structurally intact in violent sea states; the same is true for offshore oil and gas structures. While knowledge from the ship and offshore sectors can be valuable for designing wave energy converters (WECs) for survival in rough seas, the unique scale, siting and operational characteristics of WECs pose a distinct set of engineering challenges. This paper seeks to provide a review of methods for modeling the loading and dynamic response of WECs and analogue marine structures, such as ships and offshore structures, in large nonlinear waves. We identify current knowledge gaps in our understanding of WEC survivability and provide recommendations for future research to close these gaps. U.S. Department of Energy Wind and Water Power Program

For approximately 160,000 years, Earth s conditions have been in favor for humankind, thank to the biospheric life support system. Currently, anthropogenic wastes, from hazardous chemicals to carbon dioxide, are damaging the biospheric life support system at a rate unprecedented in human history. Even though scientific evidence of global heating and other types of climate change is overwhelming, unsustainable practices continue and consequences worsen. Humankind may suffer horrendous even before it accepts responsibility for the severe, possibly irreversible, damage to the biospheric life support system. Supplementary information is included in a separate file

This publication compares fluorescent and incandescent lighting and explains how fluorescent bulbs save energy and money.

Presentation on the effects of forest decentralization reforms in Uganda on both forest sustainability and livelihoods. Presents findings of data gathered using the Poverty and Environment Network method. LTRA-1 (Decentralization Reforms and Property Rights)