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NIST produces large-format, dual-polarization-sensitive detector arrays for a broad range of frequencies (30-1400 GHz). Such arrays enable a host of astrophysical measurements. Detectors optimized for cosmic microwave background o...
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NIST produces large-format, dual-polarization-sensitive detector arrays for a broad range of frequencies (30-1400 GHz). Such arrays enable a host of astrophysical measurements. Detectors optimized for cosmic microwave background observations are monolithic, polarization-sensitive arrays based on feedhorn and planar Nb antenna-coupled transition-edge superconducting (TES) bolometers. Recent designs achieve multiband, polarimetric sensing within each spatial pixel. In this proceeding, we describe our multichroic, feedhorn-coupled design; demonstrate performance at 70-380 GHz; and comment on current developments for implementation of these detector arrays in the advanced Atacama Cosmology Telescope receiver
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Goal-Driven Autonomy (GDA) is a model for online planning extended with dynamic goal selection. GDA has been investigated in the context of numerous abstract planning domains, and there has been recent interest in applying GDA to ...
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Goal-Driven Autonomy (GDA) is a model for online planning extended with dynamic goal selection. GDA has been investigated in the context of numerous abstract planning domains, and there has been recent interest in applying GDA to control unmanned vehicles. In robotic domains, certain continuous state features from sensor data must be modeled for reasoning. However, modeling these features precisely during planning and execution monitoring may be problematic, due to the inefficiency of computing exact values or sensitivity to noise. We present PHOBOS, a Hierarchical Task Network planner with bounded expectations, which we apply with a GDA agent in an underwater vehicle domain. Bounded expectations allow an agent to plan and detect discrepancies more efficiently and with fewer false discrepancies (i.e., detected but semantically meaningless differences from expectations during execution). We describe an initial simulation study that supports this claim.
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Future arcminute resolution polarization data from ground-based Cosmic Microwave Background (CMB) observations can be used to estimate the contribution to the temperature power spectrum from the primary anisotropies and to uncover...
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Future arcminute resolution polarization data from ground-based Cosmic Microwave Background (CMB) observations can be used to estimate the contribution to the temperature power spectrum from the primary anisotropies and to uncover the signature of reionization near l = 1500 in the small angular-scale temperature measurements. Our projections are based on combining expected small-scale E-mode polarization measurements from Advanced ACTPol in the range 300 < l < 3000 with simulated temperature data from the full Planck mission in the low and intermediate l region, 2 < l < 2000. We show that the six basic cosmological parameters determined from this combination of data will predict the underlying primordial temperature spectrum at high multipoles to better than 1% accuracy. Assuming an efficient cleaning from multi-frequency channels of most foregrounds in the temperature data, we investigate the sensitivity to the only residual secondary component, the kinematic Sunyaev-Zel'dovich (kSZ) term. The CMB polarization is used to break degeneracies between primordial and secondary terms present in temperature and, in effect, to remove from the temperature data all but the residual kSZ term. We estimate a 15 sigma detection of the di use homogeneous kSZ signal from expected AdvACT temperature data at l > 1500, leading to a measurement of the amplitude of matter density fluctuations, sigma 8, at 1% precision.
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Unmanned vehicles have been the focus of active research on autonomous motion planning, both deliberative and reactive. However, they are fundamentally limited in their autonomy by an inability to independently reason about, prior...
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Unmanned vehicles have been the focus of active research on autonomous motion planning, both deliberative and reactive. However, they are fundamentally limited in their autonomy by an inability to independently reason about, prioritize, and change the goals they pursue. We describe two new projects in which we are incorporating goal autonomy on unmanned vehicle platforms. We will apply the Goal-Driven Autonomy (GDA) model to permit our vehicles to reason about their objectives and discuss how properties of the domains affect the application of GDA.
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This report describes the kernel density estimation technique and its application to range safety applications. The kernel density estimation technique is shown to be suitable for developing probabilistic risk assessments from gro...
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This report describes the kernel density estimation technique and its application to range safety applications. The kernel density estimation technique is shown to be suitable for developing probabilistic risk assessments from ground impact data generated for guided weapon systems via Monte Carlo simulations. An advantage of this technique is that it can be used to predict the probability density function for minimal simulated ground impacts with apparently random distribution. Several techniques have been proposed to ameliorate the identified limitations of the kernel density estimation technique, including a covariant form for two-dimensional data. Analysis of the available simulated guided weapon ground impact data has identified that around six hundred impact points are sufficient for generating a probability distribution.
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Automated orthorectification of raw image products is now possible based on the comprehensive metadata collected by Global Positioning Systems and Inertial Measurement Unit technology aboard aircraft and satellite digital imaging ...
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Automated orthorectification of raw image products is now possible based on the comprehensive metadata collected by Global Positioning Systems and Inertial Measurement Unit technology aboard aircraft and satellite digital imaging systems, and based on emerging pattern-matching and automated image-to- image and control point selection capabilities in many advanced image processing systems. Automated orthorectification of standard aerial photography is also possible if a camera calibration report and sufficient metadata is available. Orthorectification of historical imagery, for which only limited metadata was available, was also attempted and found to require some user input, creating a semi-automated process that still has significant potential to reduce processing time and expense for the conversion of archival historical imagery into geospatially enabled, digital formats, facilitating preservation and utilization of a vast archive of historical imagery. Over 90 percent of the frames of historical aerial photos used in this experiment were successfully orthorectified to the accuracy of the USGS 100K base map series utilized for the geospatial reference of the archive. The accuracy standard for the 100K series maps is approximately 167 feet (51 meters). The main problems associated with orthorectification failure were cloud cover, shadow and historical landscape change which confused automated image-to-image matching processes. Further research is recommended to optimize automated orthorectification methods and enable broad operational use, especially as related to historical imagery archives.
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This study estimated energy, environmental and consumer economic impacts of U.S. federal residential energy efficiency standards that became effective in the 1988-2001 period or will take effect by the end of 2007. These standards...
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This study estimated energy, environmental and consumer economic impacts of U.S. federal residential energy efficiency standards that became effective in the 1988-2001 period or will take effect by the end of 2007. These standards have been the subject of in-depth analyses conducted as part of DOE's standards rulemaking process. This study drew on those analyses, but updated certain data and developed a common framework and assumptions for all of the products in order to estimate realized impacts and to update projected impacts. We estimate that the considered standards will reduce residential primary energy consumption and carbon dioxide emissions in 2020 by 8% compared to the levels expected without any standards. They will save a cumulative total of 34 quads by 2020, and 54 quads by 2030. The estimated cumulative net present value of consumer benefit amounts to $93 billion by 2020, and grows to $125 billion by 2030. The overall benefit/cost ratio of cumulative consumer impacts is 2.45 to 1. While the results of this study are subject to a fair degree of uncertainty, we believe that the general conclusions - DOE's energy efficiency standards save significant quantities of energy (and associated carbon emissions) and reduce consumers' net costs - are robust.
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Energy efficiency standards set minimum levels of energy efficiency that must be met by new products. Depending on the dynamics of the market and the level of the standard, the effect on the market for a given product may be small...
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Energy efficiency standards set minimum levels of energy efficiency that must be met by new products. Depending on the dynamics of the market and the level of the standard, the effect on the market for a given product may be small, moderate, or large. Energy efficiency standards address a number of market failures that exist in the buildings sector. Decisions about efficiency levels often are made by people who will not be responsible for the energy bill, such as landlords or developers of commercial buildings. Many buildings are occupied for their entire lives by very temporary owners or renters, each unwilling to make long-term investments that would mostly reward subsequent users. And sometimes what looks like apathy about efficiency merely reflects inadequate information or time invested to evaluate it. In addition to these sector-specific market failures, energy efficiency standards address the endemic failure of energy prices to incorporate externalities. In the U.S., energy efficiency standards for consumer products were first implemented in California in 1977. National standards became effective starting in 1988. By the end of 2001, national standards were in effect for over a dozen residential appliances, as well as for a number of commercial sector products.
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In support of the federal governments efforts to raise the minimum energy-efficiency standards for residential-type central air conditioners and heat pumps, a consumer life-cycle cost (LCC) analysis was conducted to demonstrate th...
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In support of the federal governments efforts to raise the minimum energy-efficiency standards for residential-type central air conditioners and heat pumps, a consumer life-cycle cost (LCC) analysis was conducted to demonstrate the economic impacts on individual consumers from revisions to the standards. LCC is the consumers cost of purchasing and installing an air conditioner or heat pump and operating the unit over its lifetime. The LCC analysis is conducted on a nationally representative sample of air conditioner and heat pump consumers resulting in a distribution of LCC impacts showing the percentage of consumers that are either benefitting or being burdened by increased standards. Relative to the existing minimum efficiency standard of 10 SEER, the results show that a majority of split system air conditioner and heat pump consumers will either benefit or be insignificantly impacted by increased efficiency standards of up to 13 SEER.
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In recent years, Latin America's hydrocarbons sector has been characterized by reorganization, revitalization, regional cooperation, environmental awakening, and steady expansion. The pattern of these changes, which appear to be t...
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In recent years, Latin America's hydrocarbons sector has been characterized by reorganization, revitalization, regional cooperation, environmental awakening, and steady expansion. The pattern of these changes, which appear to be the megatrends of the region's hydrocarbons sector development, will continue during the rest of the 1990s. To further study the current situation and future prospects of Latin America's hydrocarbons sector, we critically summarize in this short article the key issues in the region's oil and gas development. These megatrends in Latin America's hydrocarbons sector development will impact not only the future energy demand and supply in the region, but also global oil flows in the North American market and across the Pacific Ocean. Each country is individually discussed; pipelines to be constructed are discussed also.
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