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Publication Leveraging patent analysis to measure relatedness between technology domains: an application on offshore wind energy(2024) Wang, Yiwen; Baker, Erin; Goldstein, AnnaAs the global energy sector transitions towards a cleaner and more sustainable future, observational evidence suggests that many new energy technologies share a close relationship with well-established technologies. Yet, the topic of how closely technologies are related has not been addressed rigorously, rather it has been the purview of practitioner know-how and informal expert opinion. In this study, we propose a quantitative method to supplement practitioners' subjective understanding of the relatedness between technology domains. The method uses patents to represent the position of a technology in knowledge space and calculates the Hausdorff distance between patent domains to proxy the relatedness between technologies. We apply this method to investigate the relatedness of offshore wind energy technology to two more mature domains: onshore wind energy technology and offshore oil and gas technology. We examine the technological relatedness of individual offshore wind components to these two technologies, and represent the changes in relatedness through time. The results confirm that offshore wind components such as foundations, installation, and maintenance are more related to the offshore oil and gas industry; while other components, such as rotors and nacelles, are more related to onshore wind energy. The results also suggest that many offshore wind energy components are becoming less related through time to both of these domains, possibly indicating increasing innovation. This method can provide quantitative parameters to improve the modeling of technological change and guide practitioners in strategic decision-making regarding the positioning of industries and firms within those industries.Publication Effects of Behavior-Based Driver Feedback Systems on the Speeding Violations of Commercial Long-Haul Truck Drivers(2024) Pradhan, Anuj; Lin, Brian; Wege, Claudia; Babel, FranziskaA third of large truck crashes are associated with driver-related factors, especially speeding. This study aimed to examine the impact of behavior-based safety (BBS) programs on speeding. Speeding data were examined from a trucking fleet that had incorporated a BBS program using in-vehicle data recorders (IVDR) and post hoc feedback. Speeding events were examined over 37 weeks in two stages—an initial 4-week period (Stage 1), and the final 30 weeks (Stage 2). In Stage 1, data were collected without any feedback. In Stage 2, a subset of the drivers received feedback. A cluster analysis was performed based on the speeding event rate from Stage 1. The analysis yielded two clusters per group based on risk. The higher-risk cluster contained fewer drivers and showed a greater reduction in speeding with the BBS program, compared to the lower-risk cluster. Both clusters showed significant decreases in speeding across Stage 2. The BBS program was associated with reduced speeding, with a more pronounced reduction for the higher-risk drivers, highlighting the role of BBS programs in trucking and underscoring the importance of driver sub-groups. Targeted safety approaches may be more efficient and yield higher safety benefits than a one-size fits all approach.Publication Encapsulating commercial accelerometers with epoxy and fluoroelastomer for harsh hydrocarbon fluid environment(2023) Wankhede, Sahil Premprakash; Du, Xian; Brashler, Keith W.; Ba'adani, Mohammad M.; Turcan, Doru C.; Shehri, Ali H.; Youcef-Toumi, KamalTraditionally, in the oil and gas industry, accelerometers are mounted externally on motors for condition monitoring of vertically suspended, closed suction hydrocarbon pumps due to their inability to withstand harsh downhole environments, preventing the detection of impeller failures. This study addresses the need for encapsulation solutions for accelerometers submerged in hydrocarbon fluid environments. It evaluates the feasibility of epoxy and fluoroelastomer as encapsulation materials for long-term immersion in high-temperature hydrocarbon fluid and determines their impact on the accelerometer's performance. Extensive testing involved submersion in high-temperature hydrocarbon fluid at 150 °C for over 10,000 h and six months in brine. Material characterization, including mass variation, microscopic imaging, and FTIR spectroscopy, revealed negligible degradation. Encapsulated accelerometers effectively detected vibrations with an acceptable alteration in amplitude. In comparison with commercial alternatives, our encapsulation outperformed them. While oil traces became evident within just 24 h in the alternatives, our solution exhibited no signs of leakage. This research pioneers a novel packaging solution employing epoxy and fluoroelastomer for side-exit commercial sensors tailored for high-temperature hydrocarbon fluid applications, addressing a critical gap in the industry. Our work enhances reliability and safety for vertical oil pump condition monitoring in downhole applications, benefiting the oil and gas sector.Publication The Effect of Driving Style on Responses to Unexpected Vehicle Cyberattacks(2023-01) Zhang, Fangda; Wang, Meng; Parker, Jah'inaya; Roberts, ShannonVehicle cybersecurity is a serious concern, as modern vehicles are vulnerable to cyberattacks. How drivers respond to situations induced by vehicle cyberattacks is safety critical. This paper sought to understand the effect of human drivers’ risky driving style on response behavior to unexpected vehicle cyberattacks. A driving simulator study was conducted wherein 32 participants experienced a series of simulated drives in which unexpected events caused by vehicle cyberattacks were presented. Participants’ response behavior was assessed by their change in velocity after the cybersecurity events occurred, their post-event acceleration, as well as time to first reaction. Risky driving style was portrayed by scores on the Driver Behavior Questionnaire (DBQ) and the Brief Sensation Seeking Scale (BSSS). Half of the participants also received training regarding vehicle cybersecurity before the experiment. Results suggest that when encountering certain cyberattack-induced unexpected events, whether one received training, driving scenario, participants’ gender, DBQ-Violation scores, together with their sensation seeking measured by disinhibition, had a significant impact on their response behavior. Although both the DBQ and sensation seeking have been constantly reported to be linked with risky and aberrant driving behavior, we found that drivers with higher sensation seeking tended to respond to unexpected driving situations induced by vehicle cyberattacks in a less risky and potentially safer manner. This study incorporates not only human factors into the safety research of vehicle cybersecurity, but also builds direct connections between drivers’ risky driving style, which may come from their inherent risk-taking tendency, to response behavior to vehicle cyberattacks.Publication Reynolds and Froude number scaling in stably-stratified flows(2004-01) de Bruyn Kops, SM; Riley, JJ; Winters, KBPublication Large-eddy simulation of a reacting scalar mixing layer with arrhenius chemistry(2003-01) de Bruyn Kops, SM; Riley, JJPublication Dynamics of turbulence strongly influenced by buoyancy(2003-01) Riley, JJ; de Bruyn Kops, SMPublication Relationship between vertical shear rate and kinetic energy dissipation rate in stably stratified flows(2006-01) Hebert, DA; de Bruyn Kops, SMPublication Direct numerical simulations of the double scalar mixing layer. Part I: Passive scalar mixing and dissipation(2006-01) Cha, CM; de Bruyn Kops, SM; Mortensen, MPublication Conditional mixing statistics in a self-similar scalar mixing layer(2005-01) de Bruyn Kops, SM; Mortensen, MPublication Predicting turbulence in flows with strong stable stratification(2006-01) Hebert, DA; de Bruyn Kops, SMPublication Direct numerical simulations of the double scalar mixing layer Part II: Reactive scalars(2007-01) Mortensen, M; de Bruyn Kops, SM; Cha, CMPublication Modeling turbulent dissipation at low and moderate Reynolds numbers(2006-01) Perot, JB; de Bruyn Kops, SMPublication Pseudo-spectral numerical simulation of miscible fluids with a high density ratio(2007-01) Jang, Y; de Bruyn Kops, SMPublication IMPROVING CLINICAL ACCESS AND CONTINUITY THROUGH PHYSICIAN PANEL RE-DESIGN(2009-01) Stahl, J; Balasubramanian, H; Banerjee, R; Denton, BPublication FAULT-DIAGNOSIS WITH PROCESS UNCERTAINTY(1991) Danai, K; CHIN, HYPublication FLANK WEAR ESTIMATION UNDER VARYING CUTTING CONDITIONS(1991) KOREN, Y; KO, TR; ULSOY, AG; Danai, KPublication Direct numerical simulation and Lagrangian modeling of joint scalar statistics in ternary mixing(2008-01) Sawford, BL; de Bruyn Kops, SMPublication Conditional velocity statistics in the double scalar mixing layer - A mapping closure approach(2008-01) Mortensen, M; de Bruyn Kops, SMPublication AN IMPROVED MODEL FOR FORCE TRANSIENTS IN TURNING(1992) Danai, K; NAIR, R; MALKIN, S