169 research outputs found

    Indicators of Climate Change in the Northeast 2005

    Get PDF
    Climate changes. It always has and always will. What is unique in modern times is that human activities are now a significant factor causing climate to change. This is evident in the recent rise in key greenhouse gases, such as carbon dioxide (CO2), in the atmosphere, and in the recent increase in global temperatures in the lower atmosphere and in the surface ocean. The evidence presented in this report clearly illustrates that climate in New England is also changing. Over the past 100 years, and especially the last 30 years, all of the climate change indicators for the region reveal a warming trend. While at this point we cannot prove conclusively that this regional warming is due to human actions, the warming is fully consistent with what we would expect from global warming caused by increasing greenhouse gas concentrations. There is no question that human induced climate change is a phenomenon that humans will have to deal with in the coming decades. The good news is that, because we are the primary source of pollution that is likely causing our atmosphere and oceans to warm, we can also do something about it by changing specific policies and behaviors. It is our hope that by presenting this information in a succinct format, more people will understand the nature and scope of the problem and, therefore, be willing to make the changes necessary to address the significant societal challenge posed by climate change

    Identifying Sources and Sinks in the Presence of Multiple Agents with Gaussian Process Vector Calculus

    Full text link
    In systems of multiple agents, identifying the cause of observed agent dynamics is challenging. Often, these agents operate in diverse, non-stationary environments, where models rely on hand-crafted environment-specific features to infer influential regions in the system's surroundings. To overcome the limitations of these inflexible models, we present GP-LAPLACE, a technique for locating sources and sinks from trajectories in time-varying fields. Using Gaussian processes, we jointly infer a spatio-temporal vector field, as well as canonical vector calculus operations on that field. Notably, we do this from only agent trajectories without requiring knowledge of the environment, and also obtain a metric for denoting the significance of inferred causal features in the environment by exploiting our probabilistic method. To evaluate our approach, we apply it to both synthetic and real-world GPS data, demonstrating the applicability of our technique in the presence of multiple agents, as well as its superiority over existing methods.Comment: KDD '18 Proceedings of the 24th ACM SIGKDD International Conference on Knowledge Discovery & Data Mining, Pages 1254-1262, 9 pages, 5 figures, conference submission, University of Oxford. arXiv admin note: text overlap with arXiv:1709.0235

    Generating and using truly random quantum states in Mathematica

    Full text link
    The problem of generating random quantum states is of a great interest from the quantum information theory point of view. In this paper we present a package for Mathematica computing system harnessing a specific piece of hardware, namely Quantis quantum random number generator (QRNG), for investigating statistical properties of quantum states. The described package implements a number of functions for generating random states, which use Quantis QRNG as a source of randomness. It also provides procedures which can be used in simulations not related directly to quantum information processing.Comment: 12 pages, 3 figures, see http://www.iitis.pl/~miszczak/trqs.html for related softwar

    Observations and Recommendations for the Calibration of Landsat 8 OLI and Sentinel 2 MSI for Improved Data Interoperability

    Get PDF
    Combining data from multiple sensors into a single seamless time series, also known as data interoperability, has the potential for unlocking new understanding of how the Earth functions as a system. However, our ability to produce these advanced data sets is hampered by the differences in design and function of the various optical remote-sensing satellite systems. A key factor is the impact that calibration of these instruments has on data interoperability. To address this issue, a workshop with a panel of experts was convened in conjunction with the Pecora 20 conference to focus on data interoperability between Landsat and the Sentinel 2 sensors. Four major areas of recommendation were the outcome of the workshop. The first was to improve communications between satellite agencies and the remote-sensing community. The second was to adopt a collections-based approach to processing the data. As expected, a third recommendation was to improve calibration methodologies in several specific areas. Lastly, and the most ambitious of the four, was to develop a comprehensive process for validating surface reflectance products produced from the data sets. Collectively, these recommendations have significant potential for improving satellite sensor calibration in a focused manner that can directly catalyze efforts to develop data that are closer to being seamlessly interoperable
    corecore