Hasil untuk "Communities. Classes. Races"

É. Balibar, I. Wallerstein

Takao Inoué

We develop a theory of chirality and racemization on isotopy classes of finite loops, formulated intrinsically within the loop isotopy groupoid understood in the categorical sense. Motivated by earlier work on quasigroups \cite{InoueQuasiChirality} and by the classical medical paradigm of mirror-related enantiomers, we restrict admissible mirror transitions to those generated by intrinsic, unit-preserving symmetries. Within this framework, racemization is modeled as a two-state dynamics on isotopy classes, with an effective rate determined by the presence of mirror-isotopisms. Our main result shows that this rate vanishes if and only if no loop isotopism exists between a loop and its opposite, providing a structural criterion for chirality. A strengthened variant based on translation-generated symmetries is discussed in the appendix.

Johanna Senk, Anno C. Kurth, Steve Furber et al.

The local circuitry of the mammalian brain is a focus of the search for generic computational principles because it is largely conserved across species and modalities. In 2014 a model was proposed representing all neurons and synapses of the stereotypical cortical microcircuit below $1\,\text{mm}^2$ of brain surface. The model reproduces fundamental features of brain activity but its impact remained limited because of its computational demands. For theory and simulation, however, the model was a breakthrough because it removes uncertainties of downscaling, and larger models are less densely connected. This sparked a race in the neuromorphic computing community and the model became a de facto standard benchmark. Within a few years real-time performance was reached and surpassed at significantly reduced energy consumption. We review how the computational challenge was tackled by different simulation technologies and derive guidelines for the next generation of benchmarks and other domains of science.

Grzegorz Czechmanowski, Jan Węgrzynowski, Piotr Kicki et al.

Fully autonomous vehicles promise enhanced safety and efficiency. However, ensuring reliable operation in challenging corner cases requires control algorithms capable of performing at the vehicle limits. We address this requirement by considering the task of autonomous racing and propose solving it by learning a racing policy using Reinforcement Learning (RL). Our approach leverages domain randomization, actuator dynamics modeling, and policy architecture design to enable reliable and safe zero-shot deployment on a real platform. Evaluated on the F1TENTH race car, our RL policy not only surpasses a state-of-the-art Model Predictive Control (MPC), but, to the best of our knowledge, also represents the first instance of an RL policy outperforming expert human drivers in RC racing. This work identifies the key factors driving this performance improvement, providing critical insights for the design of robust RL-based control strategies for autonomous vehicles.

Devin Thomas, Junqi Jiang, Avinash Kori et al.

In Formula One, teams compete to develop their cars and achieve the highest possible finishing position in each race. During a race, however, teams are unable to alter the car, so they must improve their cars' finishing positions via race strategy, i.e. optimising their selection of which tyre compounds to put on the car and when to do so. In this work, we introduce a reinforcement learning model, RSRL (Race Strategy Reinforcement Learning), to control race strategies in simulations, offering a faster alternative to the industry standard of hard-coded and Monte Carlo-based race strategies. Controlling cars with a pace equating to an expected finishing position of P5.5 (where P1 represents first place and P20 is last place), RSRL achieves an average finishing position of P5.33 on our test race, the 2023 Bahrain Grand Prix, outperforming the best baseline of P5.63. We then demonstrate, in a generalisability study, how performance for one track or multiple tracks can be prioritised via training. Further, we supplement model predictions with feature importance, decision tree-based surrogate models, and decision tree counterfactuals towards improving user trust in the model. Finally, we provide illustrations which exemplify our approach in real-world situations, drawing parallels between simulations and reality.

Marwa Fawaz, Naglaa Ali Megahed, Basma N. El-Mowafy et al.

Abstract One trend in building design is building envelopes with perforated patterns, which create a sculptural envelope using parametric and generative design tools to adapt to environmental conditions and user preferences. However, there are gaps in understanding the potential benefits of perforated building envelopes (PBEs) and their key design parameters used in contemporary projects. Therefore, this study aims to examine the classification of PBE design parameters and their commonly used parametric design tools that provide appropriate indoor environmental quality (IEQ) for buildings. The study is based on (1) a review of relevant studies, and (2) an analysis of case studies of contemporary projects. The results reveal relationships between key design variables of contemporary PBEs based on a conceptual framework developed in terms of (a) general building properties, (b) detailed envelope properties, and (c) environmental performance indicators. This study contributes to the field of architecture by providing a design strategy for creating PBEs based on a parametric approach and highlights the importance of considering IEQ in the early digital modelling process. By applying the five-stage strategy: creativity, configuration, generation, performance, and evaluation, it was found that PBEs can be a powerful tool to enhance energy efficiency by about 26.91% compared to glazed envelopes in Egypt, which may lead to improved IEQ. Future research could apply the proposed strategy to explore the impact of PBEs on various IEQ indicators.

Sergio Antonio Monroy Isaza, Diego Guevara-Casañeda, Luisa Fernada Tovar et al.

Los faros agroecológicos son proyectos a escala local llevados a cabo por diversos actores articulados en una búsqueda colectiva de transformación del sistema agroalimentario. Algunos de estos actores son neorrurales, migrantes voluntarios que buscan una mejor calidad de vida en su tránsito hacia la ruralidad. Desde la propuesta de redes enraizadas, el artículo busca analizar las relaciones de poder situadas que pueden emerger en el marco de la interacción neorrural, a propósito de los procesos de conformación de una red de faros agroecológicos en la Provincia de Oriente de Cundinamarca (Colombia). A partir de la información recolectada en campo, se desarrolló un ejercicio de comparación para establecer categorías emergentes. Problematizar la cuestión del enraizamiento, y otras formas de relacionamiento, permite comprender cómo los procesos de resistencia (poder a pesar de) son agenciados desde un nivel comunitario y cómo se conforma un tejido robusto a partir de las relaciones de solidaridad horizontal (poder lateral), que desemboca en formas creativas de ejercicio del poder y de cualificación de la disputa (poder desde abajo).

Sümeyye Kahraman, Burak Korkmazyurek, Erkan Polat

Lokacije avtobusnih postaj so ključne za učinkovito storitev potniškega prometa in trajnostno mobilnost v mestih. Določajo možnost dostopa obiskovalcev do mesta ter varnost, dostopnost in ekonomičnost javnega prevoza. Poleg tega vplivajo na dostop prebivalcev do delovnih mest, šol, zdravstvenih in drugih osnovnih storitev ter posledično na splošno družbenogospodarsko blaginjo mesta. V članku je določena optimalna lokacija nove avtobusne postaje v turškem mestu Uşak, za kar so avtorji uporabili hibridni model večkriterijskega odločanja, ki vključuje presojo dvajsetih kriterijev in celovito analizo dostopnosti lokacij na podlagi mnenj strokovnjakov ter upošteva raznovrstne potrebe prebivalcev in lokalnih oblasti. S postopkom analitične hierarhije so merilom pripisali uteži, na podlagi česar so nato z metodami MOOSRA, ARAS in VIKOR sedem možnih lokacij razvrstili po primernosti. Izsledki so pokazali, katera lokacija bi bila najprimernejša, hkrati pa so potrdili robustnost uporabljenega modela in njegovo uporabnost v urbanističnem načrtovanju

Felicia H. M. Liu, Karen P. Y. Lai, Bertrand Seah et al.

Abstract This paper critically assesses the complex interplay between urban transitions of digitisation and sustainability. Building on a mixed-method research design, we unpack the challenges of decarbonising digital infrastructure while attending to urban sustainability goals in a land- and water-scarce country facing significant physical climate risks. We identify transferrable lessons on the economic, technological, and environmental synergies and trade-offs behind data centre development and argue that stewarding the global data centre sector towards sustainability requires an ecosystem-wide approach. We identify implementation gaps across five key dimensions: technological innovation, policy and regulation, finance, infrastructure, and people. We find that the progress and uptake of sustainability initiatives are often impeded by risk-averse DC operators, who are most concerned with real and perceived risks of downtime. We conclude with recommendations for data centre stakeholders to align the low-carbon transition of the data centre sector with broader objectives of climate resilience, smart city development, and sustainable finance.

Junqi Song, J. Bradeen, S. Naess et al.

Sukron Djazilan, Wuri Wuryandani

Character education is a pivotal element in fostering moral and ethical values among students. This study explores the synergistic impact of parental and community involvement in character education within schools. Using a qualitative phenomenological approach, data were collected through in-depth interviews, participant observations, and document analysis across three schools in diverse socio-economic settings. The findings reveal that parental involvement, such as reinforcing values at home and participating in school activities, significantly enhances students' moral development. Likewise, community engagement through mentorship, resources, and local partnerships provides a supportive environment for instilling positive character traits. However, challenges such as conflicting values, limited time, and communication gaps were identified as barriers to effective collaboration. This research underscores the importance of an integrated approach, aligning efforts between parents, community members, and educators to optimize character education outcomes. The study highlights practical strategies and theoretical contributions, advocating for enhanced communication and joint initiatives to nurture students' character development.    

Rafael Borim-de-Souza, Yasmin Shawani Fernandes, Pablo Henrique Paschoal Capucho et al.

Purpose This paper aims to analyze what Samarco and Brazilian magazines speak and say about Mariana’s environmental crime. Discover their doxa in this subject. Interpret the speakings, sayings and doxas through the theories of the treadmills of production, crime and law. Design/methodology/approach It is a qualitative and documental research and a narrative analysis. Regarding the documents: 45 were from public authorities, 14 from Samarco Mineração S.A. and 73 from Brazilian magazines. Theoretically, the authors resorted to Bourdieusian sociology (speaking, saying and doxa) and the treadmills of production, crime and law theories. Findings Samarco: speaking – mission statements; saying – detailed information and economic and financial concerns; doxa – assistance discourse. Brazilian magazines: speaking – external agents; saying – agreements; doxa – attribution, aggravations, historical facts, impacts and protests. Research limitations/implications The absence of discussions that addressed this fatality, with its respective consequences, from an agenda that exposed and denounced how it exacerbated race, class and gender inequalities. Practical implications Regarding Mariana’s environmental crime: Samarco Mineração S.A. speaks and says through the treadmill of production theory and supports its doxa through the treadmill of crime theory, and Brazilian magazines speak and say through the treadmill of law theory and support their doxa through the treadmill of crime theory. Social implications To provoke reflections on the relationship between the mining companies and the communities where they settle to develop their productive activities. Originality/value Concerning environmental crime in perspective, submit it to a theoretical interpretation based on sociological references, approach it in a debate linked to environmental criminology, and describe it through narratives exposed by the guilty company and by Brazilian magazines with high circulation.

Claudia Flores-Saviaga, Christopher Curtis, Saiph Savage

AI has revolutionized the processing of various services, including the automatic facial verification of people. Automated approaches have demonstrated their speed and efficiency in verifying a large volume of faces, but they can face challenges when processing content from certain communities, including communities of people of color. This challenge has prompted the adoption of "human-in-the-loop" (HITL) approaches, where human workers collaborate with the AI to minimize errors. However, most HITL approaches do not consider workers' individual characteristics and backgrounds. This paper proposes a new approach, called Inclusive Portraits (IP), that connects with social theories around race to design a racially-aware human-in-the-loop system. Our experiments have provided evidence that incorporating race into human-in-the-loop (HITL) systems for facial verification can significantly enhance performance, especially for services delivered to people of color. Our findings also highlight the importance of considering individual worker characteristics in the design of HITL systems, rather than treating workers as a homogenous group. Our research has significant design implications for developing AI-enhanced services that are more inclusive and equitable.

Giorgio Riva, Stefano Radrizzani, Giulio Panzani

The sustainable mobility trend touches the racing world as well, from the hybridization of Formula 1 (F1) and Le Mans Hypercars to the fully electric Formula E racing class. In this scenario, the research community is studying how to push electric racing vehicles to their limit, combining vehicle dynamics and energy management, to successfully solve the minimum lap time problem. Recently, this class of problems has been enlarged towards optimal sizing, with a particular interest in batteries, which represent the main bottleneck for electric vehicle performance. In this work, starting from a thorough review of literature approaches, we define a general optimization framework of minimum lap and race time problems for electric vehicles, suitable to figure out the impact of different modeling choices on both problem structure and optimal variables profiles. Exploiting a case study on Generation 3 (Gen 3) of Formula E cars, we delve into the impact of battery models' complexity on both optimal sizing and optimal battery usage. We show how highly detailed models are necessary to study the evolution of both battery and vehicle control variables during the race, while, simple models are more than sufficient to address the battery sizing problem.

Philip Greengard, Andrew Gelman

Bayesian Improved Surname Geocoding (BISG) is a ubiquitous tool for predicting race and ethnicity using an individual's geolocation and surname. Here we demonstrate that statistical dependence of surname and geolocation within racial/ethnic categories in the United States results in biases for minority subpopulations, and we introduce a raking-based improvement. Our method augments the data used by BISG--distributions of race by geolocation and race by surname--with the distribution of surname by geolocation obtained from state voter files. We validate our algorithm on state voter registration lists that contain self-identified race/ethnicity.

Jingyun Ning, Madhur Behl

Autonomous racing is increasingly becoming a proving ground for autonomous vehicle technology at the limits of its current capabilities. The most prominent examples include the F1Tenth racing series, Formula Student Driverless (FSD), Roborace, and the Indy Autonomous Challenge (IAC). Especially necessary, in high speed autonomous racing, is the knowledge of accurate racecar vehicle dynamics. The choice of the vehicle dynamics model has to be made by balancing the increasing computational demands in contrast to improved accuracy of more complex models. Recent studies have explored learning-based methods, such as Gaussian Process (GP) regression for approximating the vehicle dynamics model. However, these efforts focus on higher level constructs such as motion planning, or predictive control and lack both in realism and rigor of the GP modeling process, which is often over-simplified. This paper presents the most detailed analysis of the applicability of GP models for approximating vehicle dynamics for autonomous racing. In particular we construct dynamic, and extended kinematic models for the popular F1TENTH racing platform. We investigate the effect of kernel choices, sample sizes, racetrack layout, racing lines, and velocity profiles on the efficacy and generalizability of the learned dynamics. We conduct 400+ simulations on real F1 track layouts to provide comprehensive recommendations to the research community for training accurate GP regression for single-track vehicle dynamics of a racecar.

Kennedy Machira, Wisdom Richard Mgomezulu, Mark Malata

Poverty alleviation remains one of the ancient goals of Malawi as the country has since 1994 adopted a poverty alleviation strategy throughout its developmental programs. Through the support of the World Bank, a poverty monitoring system was put in place whose data are collected through the Living Standards Measurement Surveys (LSMS). However, since the establishment of the LSMS, findings of different assessments and eras have revealed instabilities in the country’s poverty levels overtime. What remains unclear is whether households have been able to move out of poverty or not. The current study employed a two wave LSMS panel of 2016 and 2019 and assessed poverty dimensions including poverty incidence, depth and severity. The study further assessed the determinants of poverty transitions in order to understand movements in and out of poverty. Household size, gender of household head, education level of the household head, agricultural land holding sizes, access to credit, residence (urban or rural) and expected shocks significantly influenced the poverty dimensions and poverty transition. It is hence imperative that proper strategies that embrace robust and sustainable credit systems, improvement in literacy levels of the Malawian population, and further improving agricultural land productivity can help reduce poverty and further move households out of poverty. Such initiatives should take into consideration the gender divide and the rapid population growth faced by the country.

D. Born, M. Romann, T. Stöggl

The aims of the study were to provide benchmarks and normative data for 100 m, 200 m, and 400 m short-course individual medley (IM) races, investigate differences between the various swimming strokes and turns involved in IM, and quantify the effect and contribution of various race sections on swimming performance. All IM races (n = 320) at the 2019 European Short-Course Swimming Championships were video monitored and digitized with interrater reliability described by a mean intra-class correlation coefficient of 0.968. Normative data were provided for the eight finalists of each event (FINA points = 886 ± 37) and the eight slowest swimmers from each event (FINA points = 688 ± 53). Contribution and effects of race sections on swimming performance were investigated using stepwise regression analysis based on all races of each event. Regression analysis explained 97-100% of total variance in race time and revealed turn time (β ≥ 0.53) as distinguishing factor in short-course IM races in addition to swim velocity (β ≥ -0.28). Start time only affected 100 m (β ≥ 0.14) and 200 m (β ≥ 0.04) events. Fastest turn times were found for the butterfly/backstroke turn. Breaststroke showed slowest swim velocities and no difference between fastest and slowest 100 m IM swimmers. Therefore, breaststroke may provide largest potential for future development in IM race times. Correlation analyses revealed that distance per stroke (r ≥ -0.39, P 0.05) is a performance indicator and may be used by coaches and performance analysts to evaluate stroke mechanics in male IM swimmers despite its more complex assessment. Performance analysts, coaches, and swimmers may use the present normative data to establish minimal and maximal requirements for European Championship participation and to create specific drills in practice.

Joshua Spisak, Andrew Saba, Nayana Suvarna et al.

Race cars are routinely driven to the edge of their handling limits in dynamic scenarios well above 200mph. Similar challenges are posed in autonomous racing, where a software stack, instead of a human driver, interacts within a multi-agent environment. For an Autonomous Racing Vehicle (ARV), operating at the edge of handling limits and acting safely in these dynamic environments is still an unsolved problem. In this paper, we present a baseline controls stack for an ARV capable of operating safely up to 140mph. Additionally, limitations in the current approach are discussed to highlight the need for improved dynamics modeling and learning.

O. M. Palacios-Gimenez, Julia Koelman, Marc Palmada-Flores et al.

Repetitive DNA sequences, including transposable elements (TEs) and tandemly repeated satellite DNA (satDNAs), collectively called the “repeatome”, are found in high proportion in organisms across the Tree of Life. Grasshoppers have large genomes, averaging 9 Gb, that contain a high proportion of repetitive DNA, which has hampered progress in assembling reference genomes. Here we combined linked-read genomics with transcriptomics to assemble, characterize, and compare the structure of repetitive DNA sequences in four chromosomal races of the morabine grasshopper Vandiemenella viatica species complex and determine their contribution to genome evolution. We obtained linked-read genome assemblies of 2.73–3.27 Gb from estimated genome sizes of 4.26–5.07 Gb DNA per haploid genome of the four chromosomal races of V. viatica. These constitute the third largest insect genomes assembled so far. Combining complementary annotation tools and manual curation, we found a large diversity of TEs and satDNAs, constituting 66 to 75% per genome assembly. A comparison of sequence divergence within the TE classes revealed massive accumulation of recent TEs in all four races (314–463 Mb per assembly), indicating that their large genome sizes are likely due to similar rates of TE accumulation. Transcriptome sequencing showed more biased TE expression in reproductive tissues than somatic tissues, implying permissive transcription in gametogenesis. Out of 129 satDNA families, 102 satDNA families were shared among the four chromosomal races, which likely represent a diversity of satDNA families in the ancestor of the V. viatica chromosomal races. Notably, 50 of these shared satDNA families underwent differential proliferation since the recent diversification of the V. viatica species complex. This in-depth annotation of the repeatome in morabine grasshoppers provided new insights into the genome evolution of Orthoptera. Our TEs analysis revealed a massive recent accumulation of TEs equivalent to the size of entire Drosophila genomes, which likely explains the large genome sizes in grasshoppers. Despite an overall high similarity of the TE and satDNA diversity between races, the patterns of TE expression and satDNA proliferation suggest rapid evolution of grasshopper genomes on recent timescales.