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关键词： Cryospheric science   Environmental impact   Computer science   Statistics  

摘要： Accurate seasonal forecasts of sea ice are highly valuable, particularly in the context of sea ice loss due to global warming. A new machine learning tool for sea ice forecasting offers a substantial increase in accuracy over current physics-based dynamical model predictions. Anthropogenic warming has led to an unprecedented year-round reduction in Arctic sea ice extent. This has far-reaching consequences for indigenous and local communities, polar ecosystems, and global climate, motivating the need for accurate seasonal sea ice forecasts. While physics-based dynamical models can successfully forecast sea ice concentration several weeks ahead, they struggle to outperform simple statistical benchmarks at longer lead times. We present a probabilistic, deep learning sea ice forecasting system, IceNet. The system has been trained on climate simulations and observational data to forecast the next 6 months of monthly-averaged sea ice concentration maps. We show that IceNet advances the range of accurate sea ice forecasts, outperforming a state-of-the-art dynamical model in seasonal forecasts of summer sea ice, particularly for extreme sea ice events. This step-change in sea ice forecasting ability brings us closer to conservation tools that mitigate risks associated with rapid sea ice loss.

关键词： Computer science   Economics  

摘要： Globally, there has been a recent surge in 'citizens' assemblies'(1), which are a form of civic participation in which a panel of randomly selected constituents contributes to questions of policy. The random process for selecting this panel should satisfy two properties. First, it must produce a panel that is representative of the population. Second, in the spirit of democratic equality, individuals would ideally be selected to serve on this panel with equal probability(2,3). However, in practice these desiderata are in tension owing to differential participation rates across subpopulations(4,5). Here we apply ideas from fair division to develop selection algorithms that satisfy the two desiderata simultaneously to the greatest possible extent: our selection algorithms choose representative panels while selecting individuals with probabilities as close to equal as mathematically possible, for many metrics of 'closeness to equality'. Our implementation of one such algorithm has already been used to select more than 40 citizens' assemblies around the world. As we demonstrate using data from ten citizens' assemblies, adopting our algorithm over a benchmark representing the previous state of the art leads to substantially fairer selection probabilities. By contributing a fairer, more principled and deployable algorithm, our work puts the practice of sortition on firmer foundations. Moreover, our work establishes citizens' assemblies as a domain in which insights from the field of fair division can lead to high-impact applications.

关键词： Computational biology and bioinformatics   Structural biology   Machine learning   Computer science  

摘要： [...]the original AlphaFold arguably represented only an incremental improvement over competing algorithms, in both design and performance. [...]a calibrated self-assessment of each prediction provides a reliable estimate of correctness at the level of individual amino-acid residues (Fig. 1), enabling biologists to make inferences about confidently predicted regions. [...]AlphaFold2 is applicable to whole proteins, including large ones that have multiple, independently self-assembling units - a common feature of mammalian proteins. [...]protein structures provide immediate biological insights, because they fit within established conceptual frameworks that relate a protein's structure to its function - unlike genetic sequences, which were largely inscrutable at the dawn of the genomics era.

关键词： Computer science   Education   History  

摘要： Nature’s pages report faltering computer sales in 1971, and share some science questions from a school examination in 1871.

关键词： Medical   Actuators   Path planning   Robot design   Medical robots   Surgical robots  

摘要： Purpose The following article is a "Q&A interview" conducted by Joanne Pransky of Industrial Robot Journal as a method to impart the combined technological, business and personal experience of a prominent, robotic industry PhD and innovator regarding his pioneering efforts. The paper aims to discuss these issues. Design/methodology/approach The interviewee is Dr Nabil Simaan, Professor of Mechanical Engineering, Computer Science and Otolaryngology at Vanderbilt University. He is also director of Vanderbilt's Advanced Robotics and Mechanism Applications Research Laboratory. In this interview, Simaan shares his unique perspective and approaches on his journey of trying to solve real-world problems in the medical robotics area. Findings Simaan received his BSc, MSc and PhD in mechanical engineering from the Technion - Israel Institute of Technology. He served as Postdoctoral Research Scientist in Computer Science at Johns Hopkins University. In 2005, he joined Columbia University, New York, NY, as an Assistant Professor of Mechanical Engineering until 2010, when he joined Vanderbilt. His current applied research interests include synthesis of novel robotic systems for surgical assistance in confined spaces with applications to minimally invasive surgery of the throat, natural orifice surgery, cochlear implant surgery and dexterous bimanual microsurgery. Theoretical aspects of his research include robot design and kinematics. Originality/value Dr Simaan is a leading pioneer on designing robotic systems and mechanisms for medical applications. Examples include technologies for snake robots licensed to Intuitive Surgical;technologies for micro-surgery of the retina, which led to the formation of AURIS Surgical Robotics;the insertable robotic effector platform (IREP) single-port surgery robot that served as the research prototype behind the Titan Medical Inc. Sport (Single Port Orifice Robotic Technology). Simaan received the NSF Career award for young investigators to des

关键词： Libraries  

摘要： Mainstream math libraries for floating point (FP) do not produce correctly rounded results for all inputs. In contrast, CR-LIBM and RLibm provide correctly rounded implementations for a specific FP representation with one rounding mode. Using such libraries for a representation with a new rounding mode or with different precision will result in wrong results due to double rounding. This paper proposes a novel method to generate a single polynomial approximation that produces correctly rounded results for all inputs for multiple rounding modes and multiple precision configurations. To generate a correctly rounded library for n-bits, our key idea is to generate a polynomial approximation for a representation with n + 2-bits using the round-to-odd mode. We prove that the resulting polynomial approximation will produce correctly rounded results for all five rounding modes in the standard and for multiple representations with k-bits such that |E| + 1 Copyright © 2021, The Authors. All rights reserved.

关键词： Education computing  

摘要： Since 2017, over $100 million in U.S. National Science Foundation grants have been awarded to establish new and extend existing Research Practice Partnerships (RPPs) focused on K-12 computer science (CS) education. Given this investment, what are RPPs and why is so much faith being placed in them? Their unique promise for CS K-12 education is, in part, their intentional design for bridging the gap between researchers and practitioners. In this article, we provide an overview of RPPs, their benefits and challenges, methods for assessing RPPs, and additional resources for those who want to dig deeper. © 2021 Association for Computing Machinery. All rights reserved.

关键词： Matrix algebra  

摘要： Many fundamental questions in theoretical computer science are naturally expressed as special cases of the following problem: Let G be a complex reductive group, let V be a G-module, and let v,w be elements of V . Determine if w is in the G-orbit closure of v. I explain the computer science problems, the questions in representation theory and algebraic geometry that they give rise to, and the new perspectives on old areas such as invariant theory that have arisen in light of these questions. I focus primarily on the complexity of matrix *** Codes 14L30, 68Q15, 68Q17, 15A69, 14L35, 13F20 © 2021, CC BY-NC-ND.

关键词： Biodiversity  

摘要： The world faces two interlinked crises: climate change and loss of biodiversity. Forest restoration on degraded lands and surplus croplands can play a significant role both in sequestering carbon and re-establishing bio-diversity. There is a considerable body of research and practice that addresses forest restoration. However, there has been little work by computer scientists to bring powerful computational techniques to bear on this important area of work, perhaps due to a lack of awareness. In an attempt to bridge this gap, we present our vision of how techniques from computer science, broadly speaking, can aid current practice in forest restoration. © 2021, CC BY.

关键词： Septima Clark   southeastern Georgia   voter registration   Alabama’s Black Belt   Citizenship Education Program   literacy tests   Mississippi Delta   Highlander Folk School   Sea Islands   History of the Americas   Southern Christian Leadership Conference  

ISBN: (数字)9780813067155 ISBN: (纸本)9780813066943

摘要： This book details how African American women used lessons in basic literacy to crack the foundation of white supremacy and sow seeds for collective action during the civil rights movement. Deanna Gillespie traces the history of the Citizenship Education Program (CEP), a grassroots initiative that taught people to read and write in preparation for literacy tests required for voter registration—a profoundly powerful objective in the Jim Crow South. Born in 1957 as a result of discussions between community activist Esau Jenkins, schoolteacher Septima Clark, and Highlander Folk School director Myles Horton, the CEP became a part of the Southern Christian Leadership Conference in 1961. The teachers, mostly Black women, gathered friends and neighbors in living rooms, churches, beauty salons, and community centers. Through the work of the CEP, literate black men and women were able to gather their own information, determine fair compensation for a day’s work, and register formal complaints. Drawing on teachers’ reports and correspondence, oral history interviews, and papers from a variety of civil rights organizations, Gillespie follows the growth of the CEP from its beginnings in the South Carolina Sea Islands to southeastern Georgia, the Mississippi Delta, and Alabama’s Black Belt. This book retells the story of the civil rights movement from the vantage point of activists who have often been overlooked and makeshift classrooms where local people discussed, organized, and demanded change.