41 research outputs found

    Part Affinity Field based Activity Recognition

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    This report presents work and results on Activity Recognition using Part Affinity Fields for real-time surveillance applications. Starting with a short introduction to the motivation, this report gives a detailed overview over the key idea of the pursued approach and explains the basic ideas. In addition a variety of experiments on various subjects are presented, like i) the impact of the number of input frames, ii) the impact of different simple dimensionality reduction approaches, and iii) a comparison on how multi-class and binary problem formulation influence the performance

    Radiative forcing of climate: the historical evolution of the radiative forcing concept, the forcing agents and their quantification, and applications

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    We describe the historical evolution of the conceptualization, formulation, quantification, application and utilization of “radiative forcing (RF, see e.g., IPCC, 1990)” of Earth’s climate. Basic theories of shortwave and long wave radiation were developed through the 19th and 20th centuries, and established the analytical framework for defining and quantifying the perturbations to the Earth’s radiative energy balance by natural and anthropogenic influences. The insight that the Earth’s climate could be radiatively forced by changes in carbon dioxide, first introduced in the 19th century, gained empirical support with sustained observations of the atmospheric concentrations of the gas beginning in 1957. Advances in laboratory and field measurements, theory, instrumentation, computational technology, data and analysis of well-mixed greenhouse gases and the global climate system through the 20th Century enabled the development and formalism of RF; this allowed RF to be related to changes in global-mean surface temperature with the aid of increasingly sophisticated models. This in turn led to RF becoming firmly established as a principal concept in climate science by 1990. The linkage with surface temperature has proven to be the most important application of the RF concept, enabling a simple metric to evaluate the relative climate impacts of different agents. The late 1970s and 1980s saw accelerated developments in quantification including the first assessment of the effect of the forcing due to doubling of carbon dioxide on climate (the “Charney” report, National Research Council, 1979). The concept was subsequently extended to a wide variety of agents beyond well-mixed greenhouse gases (WMGHGs: carbon dioxide, methane, nitrous oxide, and halocarbons) to short-lived species such as ozone. The WMO (1986) and IPCC (1990) international assessments began the important sequence of periodic evaluations and quantifications of the forcings by natural (solar irradiance changes and stratospheric aerosols resulting from volcanic eruptions) and a growing set of anthropogenic agents (WMGHGs, ozone, aerosols, land surface changes, contrails). From 1990s to the present, knowledge and scientific confidence in the radiative agents acting on the climate system has proliferated. The conceptual basis of RF has also evolved as both our understanding of the way radiative forcing drives climate change, and the diversity of the forcing mechanisms, have grown. This has led to the current situation where “Effective Radiative Forcing (ERF, e.g., IPCC, 2013)” is regarded as the preferred practical definition of radiative forcing in order to better capture the link between forcing and global-mean surface temperature change. The use of ERF, however, comes with its own attendant issues, including challenges in its diagnosis from climate models, its applications to small forcings, and blurring of the distinction between rapid climate adjustments (fast responses) and climate feedbacks; this will necessitate further elaboration of its utility in the future. Global climate model simulations of radiative perturbations by various agents have established how the forcings affect other climate variables besides temperature e.g., precipitation. The forcing-response linkage as simulated by models, including the diversity in the spatial distribution of forcings by the different agents, has provided a practical demonstration of the effectiveness of agents in perturbing the radiative energy balance and causing climate changes. The significant advances over the past half-century have established, with very high confidence, that the global-mean ERF due to human activity since preindustrial times is positive (the 2013 IPCC assessment gives a best estimate of 2.3 W m-2, with a range from 1.1 to 3.3 W m-2; 90% confidence interval). Further, except in the immediate aftermath of climatically-significant volcanic eruptions, the net anthropogenic forcing dominates over natural radiative forcing mechanisms. Nevertheless, the substantial remaining uncertainty in the net anthropogenic ERF leads to large uncertainties in estimates of climate sensitivity from observations and in predicting future climate impacts. The uncertainty in the ERF arises principally from the incorporation of the rapid climate adjustments in the formulation, the well-recognized difficulties in characterizing the preindustrial state of the atmosphere, and the incomplete knowledge of the interactions of aerosols with clouds. This uncertainty impairs the quantitative evaluation of climate adaptation and mitigation pathways in the future. A grand challenge in Earth System science lies in continuing to sustain the relatively simple essence of the radiative forcing concept in a form similar to that originally devised, and at the same time improving the quantification of the forcing. This, in turn, demands an accurate, yet increasingly complex and comprehensive, accounting of the relevant processes in the climate system

    Earth Resources, A Continuing Bibliography with Indexes

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    This bibliography lists 460 reports, articles and other documents introduced into the NASA scientific and technical information system between July 1 and September 30, 1984. Emphasis is placed on the use of remote sensing and geophysical instrumentation in spacecraft and aircraft to survey and inventory natural resources and urban areas. Subject matter is grouped according to agriculture and forestry, environmental changes and cultural resources, geodesy and cartography, geology and mineral resources, hydrology and water management, data processing and distribution systems, instrumentation and sensors, and economical analysis

    Clouds and the Earth's Radiant Energy System (CERES) Algorithm Theoretical Basis Document

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    The theoretical bases for the Release 1 algorithms that will be used to process satellite data for investigation of the Clouds and Earth's Radiant Energy System (CERES) are described. The architecture for software implementation of the methodologies is outlined. Volume 3 details the advanced CERES methods for performing scene identification and inverting each CERES scanner radiance to a top-of-the-atmosphere (TOA) flux. CERES determines cloud fraction, height, phase, effective particle size, layering, and thickness from high-resolution, multispectral imager data. CERES derives cloud properties for each pixel of the Tropical Rainfall Measuring Mission (TRMM) visible and infrared scanner and the Earth Observing System (EOS) moderate-resolution imaging spectroradiometer. Cloud properties for each imager pixel are convolved with the CERES footprint point spread function to produce average cloud properties for each CERES scanner radiance. The mean cloud properties are used to determine an angular distribution model (ADM) to convert each CERES radiance to a TOA flux. The TOA fluxes are used in simple parameterization to derive surface radiative fluxes. This state-of-the-art cloud-radiation product will be used to substantially improve our understanding of the complex relationship between clouds and the radiation budget of the Earth-atmosphere system

    Earth resources: A continuing bibliography with indexes (issue 61)

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    This bibliography lists 606 reports, articles, and other documents introduced into the NASA scientific and technical information system between January 1 and March 31, 1989. Emphasis is placed on the use of remote sensing and geophysical instrumentation in spacecraft and aircraft to survey and inventory natural resources and urban areas. Subject matter is grouped according to agriculture and forestry, environmental changes and cultural resources, geodesy and cartography, geology and mineral resources, oceanography and marine resources, hydrology and water management, data processing and distribution systems, and instrumentation and sensors, and economic analysis

    Earth Resources: A continuing bibliography with indexes

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    This bibliography lists 475 reports, articles and other documents introduced into the NASA scientific and technical information system between January 1 and March 31, 1984. Emphasis is placed on the use of remote sensing and geophysical instrumentation in spacecraft and aircraft to survey and inventory natural resources and urban areas. Subject matter is grouped according to agriculture and forestry, environmental changes and cultural resources, geodesy and cartography, geology and mineral resources, hydrology and water management, data processing and distribution systems, instrumentation and sensors, and economical analysis

    An integrated study of earth resources in the state of California using remote sensing techniques

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    The author has identified the following significant results. The effects on estimates of monthly volume runoff were determined separately for each of the following parameters: precipitation, evapotranspiration, lower zone and upper zone tension water capacity, imperviousness of the watershed, and percent of the watershed occupied by riparian vegetation, streams, and lakes. The most sensitive and critical parameters were found to be precipitation during the entire year and springtime evapotranspiration

    Pedestrian detection in far infrared images

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    Detection of people in images is a relatively new field of research, but has been widely accepted. The applications are multiple, such as self-labeling of large databases, security systems and pedestrian detection in intelligent transportation systems. Within the latter, the purpose of a pedestrian detector from a moving vehicle is to detect the presence of people in the path of the vehicle. The ultimate goal is to avoid a collision between the two. This thesis is framed with the advanced driver assistance systems, passive safety systems that warn the driver of conditions that may be adverse. An advanced driving assistance system module, aimed to warn the driver about the presence of pedestrians, using computer vision in thermal images, is presented in this thesis. Such sensors are particularly useful under conditions of low illumination.The document is divided following the usual parts of a pedestrian detection system: development of descriptors that define the appearance of people in these kind of images, the application of these descriptors to full-sized images and temporal tracking of pedestrians found. As part of the work developed in this thesis, database of pedestrians in the far infrared spectrum is presented. This database has been used in developing an evaluation of pedestrian detection systems as well as for the development of new descriptors. These descriptors use techniques for the systematic description of the shape of the pedestrian as well as methods to achieve invariance to contrast, illumination or ambient temperature. The descriptors are analyzed and modified to improve their performance in a detection problem, where potential candidates are searched for in full size images. Finally, a method for tracking the detected pedestrians is proposed to reduce the number of miss-detections that occurred at earlier stages of the algorithm. --La detección de personas en imágenes es un campo de investigación relativamente nuevo, pero que ha tenido una amplia acogida. Las aplicaciones son múltiples, tales como auto-etiquetado de grandes bases de datos, sistemas de seguridad y detección de peatones en sistemas inteligentes de transporte. Dentro de este último, la detección de peatones desde un vehículo móvil tiene como objetivo detectar la presencia de personas en la trayectoria del vehículo. EL fin último es evitar una colisión entre ambos. Esta tesis se enmarca en los sistemas avanzados de ayuda a la conducción; sistemas de seguridad pasivos, que advierten al conductor de condiciones que pueden ser adversas. En esta tesis se presenta un módulo de ayuda a la conducción destinado a advertir de la presencia de peatones, mediante el uso de visión por computador en imágenes térmicas. Este tipo de sensores resultan especialmente útiles en condiciones de baja iluminación. El documento se divide siguiendo las partes habituales de una sistema de detección de peatones: desarrollo de descriptores que defina la apariencia de las personas en este tipo de imágenes, la aplicación de estos en imágenes de tamano completo y el seguimiento temporal de los peatones encontrados. Como parte del trabajo desarrollado en esta tesis se presenta una base de datos de peatones en el espectro infrarrojo lejano. Esta base de datos ha sido utilizada para desarrollar una evaluación de sistemas de detección de peatones, así como para el desarrollo de nuevos descriptores. Estos integran técnicas para la descripción sistemática de la forma del peatón, así como métodos para la invariancia al contraste, la iluminación o la temperatura externa. Los descriptores son analizados y modificados para mejorar su rendimiento en un problema de detección, donde se buscan posibles candidatos en una imagen de tamano completo. Finalmente, se propone una método de seguimiento de los peatones detectados para reducir el número de fallos que se hayan producido etapas anteriores del algoritmo

    Proceedings of the 2019 Joint Workshop of Fraunhofer IOSB and Institute for Anthropomatics, Vision and Fusion Laboratory

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    In 2019 fand wieder der jährliche Workshop des Fraunhofer IOSB und des Lehrstuhls für Interaktive Echtzeitsysteme des Karlsruher Insitut für Technologie statt. Die Doktoranden beider Institutionen präsentierten den Fortschritt ihrer Forschung in den Themen Maschinelles Lernen, Machine Vision, Messtechnik, Netzwerksicherheit und Usage Control. Die Ideen dieses Workshops sind in diesem Buch gesammelt in der Form technischer Berichte

    Proceedings of the 2019 Joint Workshop of Fraunhofer IOSB and Institute for Anthropomatics, Vision and Fusion Laboratory

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    In 2019 again, the annual joint workshop of the Fraunhofer IOSB and the Vision and Fusion Laboratory of the Karlsruhe Institute of Technology took place. The doctoral students of both institutions presented extensive reports on the status of their research and discussed topics ranging from computer vision and optical metrology to network security, usage control and machine learning. The results and ideas presented at the workshop are collected in this book in the form of technical reports
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