DSpace@RPI (Rensselaer Polytechnic Institute)
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Loaded Language and Conspiracy Theories on Reddit and Parler
No full textPrevious research found that loaded language (i.e., words, phrases, and overall rhetorical strategies that have strong emotional implications and intent to sway others) is used with significantly greater frequency by users of an online anti-vaccination forum compared to users of a vaccination-neutral forum. Our present research expands on these findings by examining the presence of loaded language on forums dedicated to discussing a broader range of conspiratorial topics. We compare loaded language usage on the subreddit r/conspiracy with usage on r/science and r/wallstreetbets. Results corroborate the previous literature. We additionally examined the presence of loaded language in a dataset from the alt-tech social networking platform Parler on January 6, 2021, when the U.S. Capitol was attacked because of conspiracy theories regarding the 2020 Presidential Election. Results show that loaded language, whose usage is linked to the cognitive motivations underlying belief in conspiracy theories, is a linguistic marker of conspiracy theorizing
Autonomous navigation in deep space using optical measurements of unresolved planets and stars
No full textDecember 2022School of EngineeringOne of the essential challenges in spaceflight is spacecraft navigation. This is the estimation of the state – position, velocity, and attitude – of a spacecraft given available measurements. The development of sensors and algorithms towards this goal falls under the realm of spacecraft Guidance, Navigation, and Control (GN&C), and requires knowledge of the physics and geometry governing a specific situation. Spacecraft are generally navigated with assistance from humans on the ground, but there is increasing focus on the challenge of autonomous navigation. A spacecraft may need to be able to determine its state with no human intervention in the event of communications failure or some anomalous event, or when split-second decisions must be made in proximity of a destination several light-minutes or light-hours away from Earth. As a spacecraft travels away from Earth and other celestial bodies, into interplanetary or even interstellar space, the availability of navigation observables diminishes. This work strives to add to the body of knowledge and techniques pertaining to autonomous deep space navigation by exploring a solution to the Lost-in-Space-and-Time(LiSaT) problem using line-of-sight (LOS) measurements to unresolved planets, deriving a novel Initial Orbit Determination (IOD) algorithm using radial velocity measurements of starlight, and finding invariant properties of stars which allow for interstellar star identification and observer position estimation.Ph
Web 3.0 Meets Web3: Exploring the Convergence of Semantic Web and Blockchain Technologies
No full textWe outline the synergistic convergence of semantic web technologies, which have driven the advent
of Web 3.0, and blockchain technologies, which have catalyzed the flourishing Web3 ecosystem. The
integration of these technologies holds immense potential for transforming data representation, interoperability, and trust within decentralized knowledge graphs. The utilization of semantic web technologies
enables the creation of machine-readable data formats, facilitating seamless understanding and exchange
across heterogeneous systems. Complementing this, blockchain technologies provide an immutable and
tamper-proof ledger, offering the foundation for establishing trust in decentralized knowledge graphs.
We discuss the adoption of standardized vocabularies and smart contract powered schema alignment to
enhance data exchange and integration with a focus on semantic interoperability, trustworthiness in
semantic reasoning processes, and ownable and traceable resources
Characterizing Common Quarterly Behaviors In DeFi Lending Protocols
No full textThe emerging decentralized financial ecosystem (DeFi) is comprised of numerous protocols, one type being lending protocols. People make transactions in lending protocols, each of which is attributed to a specific blockchain address which could represent an externally-owned account (EOA) or a smart contract. Using Aave, one of the largest lending protocols, we summarize the transactions made by each address in each quarter from January 1, 2021, through December 31, 2022. We cluster these quarterly summaries to identify and name common patterns of quarterly behavior in Aave. We then use these clusters to glean insights into the dominant behaviors in Aave. We show that there are three kinds of keepers, i.e., a specific type of users tasked with the protocol’s governance, but only one kind of keeper finds consistent success in making profits from liquidations. We identify the largest-scale accounts in Aave and the highest-risk kinds of behavior on the platform. Additionally, we use the temporal aspect of the clusters to track how common behaviors change through time and how usage has shifted in the wake of major events that impacted the crypto market, and we show that there seem to be problems with user retention in Aave as many of the addresses that perform transactions do not remain in the market for long
Towards an Indoor Environmental Quality Management Ontology
No full textBuildings consume one-third of the world’s energy and are some of the major energy consumers on the planet. Occupants use this energy for enhancing indoor environmental quality (IEQ) which is affected by many factors including temperature, humidity, airflow, air quality, etc.; however, it is difficult to find a suitable general solution to improve IEQ while decreasing energy usage as each building is under different environmental conditions, and every occupant has different clothing insulation and a different metabolic rate. In this work, we propose an ontology that, based on real-time data from Internet of Things (IoT), can be used to suggest a viable solution to enhance IEQ and decrease energy usage by combining several sets of knowledge: indoor environmental conditions, outdoor environmental conditions, and occupant profiles. We demonstrated that the ontology with an application can recommend suitable actions to improve IEQ. In future work, this ontology could serve as the foundation on top of which to develop an occupant-centric building automation system for enhancing IEQ and energy efficiency, based on 3D geometric models and thermodynamic simulation modules
Air cycles in the built environment: towards a bioremediation building envelope system for improved air quality
No full textMay 2022School of ArchitectureAccording to the World Health Organization and the European Environment Agency, air pollution is the biggest environmental health risk today. Although general pollutant levels have improved in the last few decades, it is only recently that certain types of highly toxic human-made pollutants have been emitted in unprecedented quantities, primarily in developing regions. Moreover, within these geographic regions, the global population is estimated to double by 2050. The climatic context in most of these predominantly unindustrialized economic territories favors natural ventilation and the seamless interaction between indoor and outdoor spaces. Still, these areas mainly rely on mechanical systems to homogenize atmospheric living standards. Air conditioning systems produce wasted heat that alters the microclimate of buildings' surroundings while creating additional air pollution exhausted by the running cycles of equipment. To disrupt this cycle of energy expenditure and air pollution replenishment, this research proposes a hybrid air purification modular ceramic system for building envelopes in regions where fiscal means are limited, and natural ventilation is a viable option, in order to regulate both exterior and interior atmospheric pollution. This infrastructural strategy serves as a site of inquiry towards the potential amelioration of local urban pollution airstreams in the developing world.
Contrary to the majority of existing phytoremediative systems, which perform as extensions of mechanical automated systems, the proposed approach aims to redefine the function of the building envelope as a mediating boundary layer in environments conducive to natural ventilation. It represents the first of its kind system to suggest the use of potentially passive bioremediation systems as a mediator of indoor and outdoor air. The objective is to create a low-tech, high-value system, conceptualized as a combination of mechanical components, with the effectiveness and sensitivity of biological organisms. Nevertheless, rather than a specific design and development proposal, this thesis establishes a framework for multivariant evaluation of air pollution and the ways in which it may be remediated by novel phytoremediative building enclosures.
While multiple variables affect phytoremediation potential, airflow was identified as the driver of mass and energy exchange. Pressure and airflow properties of a novel envelope system's module were studied as part of simulations using Computational Fluid Dynamics (CFD), which proved itself a valuable tool to characterize airflow properties, opening new experimental opportunities for air filtration technology development. The CFD simulations was part of the process of defining the framework of this new envelope biofiltration system that regulates air pollutant removal in spaces designed for natural ventilation.
Although with this work the technical applicability of the most optimized prototype version has been established for the proposed system (AMPc), the intention was not only to provide an explicit technical solution, but also to suggest an encounter with cultural settings, based on the premise that when people lose their relationship with the environment due to air pollution, they also lose their societal cohabitation and cohesion patterns.Ph
Hemp fiber production: development of an automated peeling decorticator to produce optimal fiber for biocomposites
No full textMay 2022School of EngineeringAround the world there has been an increased focus on finding more sustainable and environmentally friendly options for a variety of manufacturing industries and practices. The composites industry, for example, is one with significant waste, a large carbon footprint, and poor end-of-life options. There has been a recent trend to reduce this impact by replacing synthetic fibers (e.g., E-glass, Aramid) with natural fibers. Hemp fiber has come forward as a competitive alternative to synthetics due to its high strength-to-weight and modulus-to-weight ratios, and its economic competitiveness when compared to other common natural fibers like cotton. Although hemp fiber has been used for centuries, there are still improvements to be made to the processing of the fiber. The current automated decortication processes – the automated process to separate the hemp fiber from its inner woody core called ‘hurd’ – is typically an aggressive process that can damage fibers and results in a tangled mess. The resulting fiber quality, while efficiently produced, is not of high enough quality to be used for advanced composite applications. This research looks to develop an automated machine that can perform decortication on hemp stalks without damaging fiber, yet allowing it to be custom-cut to length for use in high-performance biocomposite components. A novel and useful splitting and peeling decortication process is demonstrated, and a machine is developed for process automation. Specifically, flattened stalks are fed into a splitting wedge using rubber-coated pinch rollers, the stalks split into two halves, and are broken at the split ends to peel the fiber away from the intact hurd. The fiber halves are pulled sideways using two sets of pinch rollers while the splitting wedge drops downward and the peeled hurd proceeds downwards. Experiments with two machine prototypes show that this machine design and decortication process is a viable option for producing undamaged hemp fiber suitable for high-performance biocomposites, while still maintaining throughput and efficiency levels delivered by automation. While future work is required to transform this machine into a commercial product, the reliability and effectiveness of the machine has been demonstrated.M
An investigation of the pampean flat slab and its role in andean tectonics through the analysis of enhanced earthquake catalogues
No full textMay 2023School of ScienceThe Andean margin of South America is an archetypal example of a convergent tectonic environment that has played a fundamental role in the creation, evolution, and consumption of both continental and oceanic lithosphere. An enigmatic aspect of this margin is the existence of several regions of flat slab subduction, the causes and consequences of which remain poorly understood despite years of intensive investigation. The research discussed in this dissertation focuses on the Pampean flat slab beneath central Chile and Argentina, partly in response to the discovery of an unusual pattern of P wave arrival times from earthquakes beneath Argentina recorded in Chile, but also because recently developed techniques in automated phase onset estimation allow us to take significantly greater advantage of a substantial archive of seismic data that has been collected in this region over the past several decades. After constructing enhanced catalogues of seismic activity and analyzing them with various techniques of seismic tomography, the improved images of the elastic wavespeed structure of this region allow insights into the state of the subducted Nazca plate, the effects of subducting anomalous bathymetry such as ridges and seamounts shortening on the interaction between the Nazca plate and the overriding South American plate, and the consequences of lithospheric shortening of the South American plate on the geometry of the Nazca plate. We find that dense clusters of seismicity associated with the Pampean flat slab are most likely a consequence of the subduction of ridges and seamounts, and that the extensive alteration and devolatilization of the oceanic lithosphere by these features leads both to an increased buoyancy and to the release of volatiles that hydrate the South American mantle and fracture the lower crust. The existence of these features far from the trench lends support to the contention that subduction erosion is more episodic than continuous. We also find 2 low velocity anomalies, particularly in Vp, within and below the subducting slab. The western low velocity anomaly correlates with the Juan Fernandez Ridge and is postulated to be due to an increase in silica content or the presence of supercritical fluids. The eastern low velocity anomaly seems to be a result of rising hot asthenosphere. Furthermore, it appears that the gradient in wavespeeds that generated the pattern of anomalous P wave residuals that originally motivated this research may be due more to the low wavespeeds in overthickened crust beneath the high Andes grading into the higher wavespeeds of the Nazca plate, rather than a pronounced lithospheric root beneath a normal crustal root. At the same time, much of the original signal remains, which suggests that the ultimate cause of the higher apparent wavespeeds may be due as much to anisotropy as opposed to lateral heterogeneity.Ph
Employing ensemble reasoning to support clinical decision-making
No full textMay 2023School of ScienceThe combination of multiple forms of reasoning in conjunction is often used by physicians making clinical decisions. The Select and Test Model, which involves various forms of reasoning including abstraction, deduction, and abduction, is an epistemological framework that represents how reasoning can be employed in a clinical setting. While the subset of Artificial Intelligence (AI) research that is referred to as hybrid reasoning has involved the combination of various forms of reasoning, such as assertional ABox and terminological TBox reasoning, symbolic and statistical reasoning, or static and temporal reasoning, surprisingly little analysis has been conducted on the interaction between deductive and abductive reasoning. Since the term hybrid reasoning has various definitions throughout the literature, we instead refer to the integration of multiple types of reasoning as ensemble reasoning. Several challenges related to ensemble reasoning and their associated research questions naturally arise. Are the recommendations derived using our approach clinically relevant for use cases involving clinical reasoning? Are the factors used to arrive at recommendations clinically relevant? Is it clinically important or advantageous to reveal the recommendation rationale? When considering the interaction of multiple types of reasoners, does the order of reasoning make an impact on the results of the reasoning or the time it takes to obtain the results? Does an iterative approach versus an alternating approach make an impact on the results or the time it takes to obtain the results? Why might one approach be preferred over the other? Is it more efficient to split abducibles into subsets, run the abductive reasoner on each subset, and then combine the results than running an abductive reasoner with all abducibles specified? How can all interrelated abducibles be determined? We attempt to address the questions above and the soundness of our proposed approach by laying a theoretical foundation built on logical analyses. This foundation is then leveraged to design an ensemble reasoning system that we apply to several use cases related to the diagnosis and treatment of type 2 diabetes. We present the recommendations and justifications derived from our system to clinicians in order to evaluate the clinical relevance and usefulness of our approach. By implementing an evidence-based clinical decision-support system that employs ensemble reasoning, we take a step toward advancing the state-of-the-art of AI.Ph