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From Test Tracks to Carbon Tracks: Evaluating the Carbon Emissions of Autonomous Vehicle Development
No full textAutonomous vehicle (AV) development has seen a sharp increase in the past 10 years, and there is a significant energy cost of training AVs to meet safety regulations. The training process includes virtual simulation training as well as physical training on public roads and within private testing facilities. The high energy expenditure associated with AV training has a respective environmental cost that can be quantified as a lifetime “carbon debt” of released carbon emissions. The environmental sustainability of AVs has not been thoroughly studied in currently available literature, and this paper showcases a model that quantifies the total “carbon debt” and payback timeline based on efficiency levels for a specific corporation or for the global AV market. A case study of Cruise, a subsidiary of General Motors (GM) and leader in AV development, suggests that in order to meet GM’s publicized 2040 operational net-neutrality goals, Cruise’s AVs must be a minimum of 2.6% more efficient than non-AVs (Figure 5)
Alumni Spotlight: Liza Russell
No full textLiza Russell published an article in volume 10 (2020) of the Journal of Purdue Undergraduate Research during her time spent completing her baccalaureate degree
Insights from a simple mathematical model of autism spectrum disorders
No full textThis preliminary report explores insights about mechanisms of autism spectrum disorders (ASDs) gained from a mathematical model of interconnected clusters of excitatory neurons. This local, integrate-and-fire, spiking neural network is subjected to random noise from other populations of excitatory and inhibitory neurons outside the network. Its emergent behavior in response to different ratios of inhibitory to excitatory noise mimics several aspects of ASDs. The spiking neural network functions according to rules of classical neurophysiology, involving resting membrane potential, threshold potential, excitatory or inhibitory post-synaptic potentials, action potential, and refractory period. Key parameters include the incremental change in membrane potential, p , from external noise and the ratio, q , of inhibitory to excitatory external signals. With low levels of p and with q = 1 the network is quiet. Below a critical threshold level of q \u3c 1 there is sudden development of chaotic activation of all nodes in the network, simulating autistic symptoms. Transition to chaotic activation occurs at a distinct threshold of out-of-network disinhibition, q* , which depends upon the background noise level, p , according to a nonlinear function. This state function represents the autism spectrum and explains several features of ASDs—including the existence and cause of the spectrum, the tendency of patients to seek out quiet environments, and the clinical rationale for GABA boosting drugs to treat ASDs. The model provides a new and independent test of the excitatory/inhibitory mechanism, namely that loss of input from inhibitory GABAergic neurons, for any of a variety of reasons, is a final common abnormality in autism spectrum disorders. Links between this simple biologically plausible model and criticality theory are discussed
Book Review of To Save and To Destroy: Writing as An Other
No full textViet Thanh Nguyen’s To Save and to Destroy is a collection of his Norton lectures where he uses his generational stories of continuous immigration throughout Vietnam and the United States to explore how writing, with both internal and external experiences, shape our own identities, and forces that come into oppression, silence, and Otherness. In other words, the book depicts how he himself is seen from multiple others: “the Vietnamese, the Asian, the minoritized, the racialized, the colonized, the hybrid, the hyphenated, the refugee, the displaced, the artist, the writer, the smart ass, the bastard, the sympathizer, and the committed” (p. 104)
Learning to Read while Learning a Language: Reading and English Learners
No full textThe Science of Reading (SOR) is intended to benefit all children as they develop a strong foundation in reading. For a growing number of students who have proficiencies in languages other than English, how they experience SOR classroom activities differs. Students who are learning English as an additional language (English Learners) come from a variety of language backgrounds and enter at different levels of English proficiency, ranging from beginner to advanced. This research brief describes how phonemic awareness, phonics, and fluency are different for English Learners and offers advice on how to interpret their performances, differentiating instruction to address their language needs and rights
Steel Fiber Dosage in Magnesium Potassium Phosphate Cement Effects on Mechanical and Durability Properties
No full textMagnesium potassium phosphate cement (MKPC) plays a significant role as a rapid repair material in road and bridge infrastructure, owing to its fast-setting and high early strength properties. However, its crack resistance and bonding performance still pose challenges, which can impact both the repair effectiveness and the long-term service life of MKPC-based repairs. The addition of steel fibres can improve its strength and toughness. In this paper, the effect of steel fibre dosage on the processing performance and bonding properties of MKPC is investigated. The results show that the flow properties of MKPC remain stable at a dosage of 1%. Meanwhile, mechanical properties are significantly improved, with the flexural strength increasing by 56.39% and compressive strength increasing by 38.81% at this dosage. Additionally, steel fibres enhance the tensile strength of MKPC by effectively bridging cracks and preventing their propagation. After 56 days of immersion in pure water, the specimen with 1% steel fibre content retained 87% of its tensile strength, demonstrating remarkable durability. These findings indicate that steel fibre reinforcement not only improves the mechanical performance of MKPC but also enhances its long-term stability in aqueous environments, making it a promising material for durable infrastructure repairs
Enhanced global oil spill dataset from 1967 to 2023 based on text-form incident information
No full textKnowing how much oil was released into the environment in each incident is critical to studying the environmental, ecological, and economic impacts of oil spills. However, the release amounts (RAs) for numerous oil spill incidents remain unavailable in a structured format for large-scale analysis. The most extensive global oil spill database, managed by NOAA’s Office of Response and Restoration, only documents the worst-case scenario estimations in the machine-readable dataset, while more accurate values are embedded within unstructured incident descriptions and subsequent updates. To enhance the dataset with more accurate RAs, we developed a framework to extract the actual RAs from textual data considering whether spillage was confirmed and the timeliness of the information. The enhanced dataset includes 3,550 oil spill incidents from 1967 to 2023, with their actual RAs confirmed or updated using the text-form information, improving the accuracy of global oil spill data. By supplementing the original potential maximum RAs with the actual RAs information, this dataset can support more accurate risk and environmental impacts assessment of oil spills
Comparative Analysis of Loss of Control Definitions
Get PDF“Loss of control” (LOC) is a broad term in aviation used to describe an event or series of events that resulted in an accident or incident of an aircraft. Many definitions of LOC exist for aircraft while maneuvering on the ground and in the air. The purpose of this study is to synthesize the numerous LOC definitions found in the literature and from government and rulemaking organizations to better understand the importance of airspeed awareness as it relates to LOC events at low altitudes. Furthermore, emphasis shall be placed specifically on flight training within general aviation, as significant LOC statistical data exists in the flight training environment through initiatives such as the National General Aviation Flight Information Database (NGAFID). Various definitions of LOC exist and are found in different locations. This essay seeks to bring different together definitions and conclusions regarding LOC to create a better understanding and, most importantly, reduce LOC occurrences in all types of aircraft operation