68,191 research outputs found

    Guidelines for data collection and monitoring for asset management of New Zealand road bridges

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    Evaluation of City Planning Road Development Measures by Microscopic Traffic Simulation

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    This study was made on the development plan of Kawahara Avenue, a road project authorized in city planning of Miyazaki City in Japan. The Kawahara Avenue development is planned along the Oyodo River. The land use of the area along the route comprises the tourist hotel zone, residential zone, and industrial zone. The Kawahara Avenue planning, unlike most other road development plans in Japan, requires much more than simply providing for the smooth flow of traffic. In the tourist hotel zone where the leading Miyazaki City hotels are located, the image and impression the tourists may have about the city is an important consideration. Therefore, the city government intends that this section of the road should not have excessive traffic. In the residential zone, the existing road network consists of narrow streets with no sidewalks. In addition to the sidewalks to be built, Kawahara Avenue is expected to handle a great deal of the traffic passing the residential district. This should help meet the goal in providing a safe environment for the pedestrians in other narrow streets without sidewalks. Under the circumstances as stated above, the planning has faced significant constraints in land purchasing involving forced move-out in the result of financial problems and coordination of the views between the city administration and the residents in the vicinity. The purpose of this research is to study under the given constraints what would be the most appropriate plan for the development of Kawahara Avenue. First, a traffic monitoring survey was conducted in the subject districts to compile Origin-Destination (OD) data of traffic flow in the districts. Then, the road network of the subject districts and traffic signal phase data were digitized to carry out microscopic traffic simulation and checked for reproduction accuracy of the current situation. The results confirmed that simulation reproduces the traffic conditions of the districts with sufficient precision. Furthermore, we prepared several hypothetical proposals for the road development and evaluated with the same simulation system as to how the traffic situations would be had those proposals been implemented. As a result it was demonstrated that the original goals can be achieved by developing the road within the given constraints.

    Unpulsed UBV Optical Emission from the Crab Pulsar

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    Based on observations of the Crab pulsar using the TRIFFID high speed imaging photometer in the UBV bands using the Special Astrophysical Observatory's 6m telescope in the Russian Caucasus, we report the detection of pronounced emission during the so-called `off' phase of emission. Following de-extinction, this unpulsed component of emission is shown to be consistent with a power law with an exponent of alpha = -0.60 +/- 0.37, the uncertainty being dominated by the error associated with the independent CCD photometry used to reference the TRIFFID data. This suggests a steeper power law form than that reported elsewhere in the literature for the total integrated spectrum, which is essentially flat with alpha ~ 0.1, although the difference in this case is only significant at the ~ 2 sigma level. Deeper reference integrated and TRIFFID phase-resolved photometry in these bands in conjunction with further observations in the UV and R region would constrain this fit further.Comment: 26 pages, 2 figures, uses aasms4.sty, accepted for publication in the Astrophysical Journa

    An Integrated Approach for Characterizing Aerosol Climate Impacts and Environmental Interactions

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    Aerosols exert myriad influences on the earth's environment and climate, and on human health. The complexity of aerosol-related processes requires that information gathered to improve our understanding of climate change must originate from multiple sources, and that effective strategies for data integration need to be established. While a vast array of observed and modeled data are becoming available, the aerosol research community currently lacks the necessary tools and infrastructure to reap maximum scientific benefit from these data. Spatial and temporal sampling differences among a diverse set of sensors, nonuniform data qualities, aerosol mesoscale variabilities, and difficulties in separating cloud effects are some of the challenges that need to be addressed. Maximizing the long-term benefit from these data also requires maintaining consistently well-understood accuracies as measurement approaches evolve and improve. Achieving a comprehensive understanding of how aerosol physical, chemical, and radiative processes impact the earth system can be achieved only through a multidisciplinary, inter-agency, and international initiative capable of dealing with these issues. A systematic approach, capitalizing on modern measurement and modeling techniques, geospatial statistics methodologies, and high-performance information technologies, can provide the necessary machinery to support this objective. We outline a framework for integrating and interpreting observations and models, and establishing an accurate, consistent, and cohesive long-term record, following a strategy whereby information and tools of progressively greater sophistication are incorporated as problems of increasing complexity are tackled. This concept is named the Progressive Aerosol Retrieval and Assimilation Global Observing Network (PARAGON). To encompass the breadth of the effort required, we present a set of recommendations dealing with data interoperability; measurement and model integration; multisensor synergy; data summarization and mining; model evaluation; calibration and validation; augmentation of surface and in situ measurements; advances in passive and active remote sensing; and design of satellite missions. Without an initiative of this nature, the scientific and policy communities will continue to struggle with understanding the quantitative impact of complex aerosol processes on regional and global climate change and air quality

    Design definition of a mechanical capacitor

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    A design study and analyses of a 10 kW-hr, 15 kW mechanical capacitor system was studied. It was determined that magnetically supported wheels constructed of advanced composites have the potential for high energy density and high power density. Structural concepts are analyzed that yield the highest energy density of any structural design yet reported. Particular attention was paid to the problem of 'friction' caused by magnetic and I to the second power R losses in the suspension and motor-generator subsystems, and low design friction levels have been achieved. The potentially long shelf life of this system, and the absence of wearing parts, provide superior performance over conventional flywheels supported with mechanical bearings. Costs and economies of energy storage wheels were reviewed briefly

    RRS James Cook Cruise 30, 26 Dec 2008-30 Jan 2009. Antarctic Deep Water Rates of Export (ANDREX)

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    This report describes scientific activities on RRS James Cook cruise 30, “ANDREX”, westwards from 30°E and in the vicinity of latitude 60°S, between late December 2008 and late January 2009. The cruise was terminated about halfway through by a medical emergency. Hydrographic work comprised 27 CTD/LADCP stations. Water samples were captured for measurement of salinity, dissolved oxygen, inorganic nutrients, oxygen isotope fraction, chlorofluorocarbons and sulphur hexafluoride, dissolved inorganic carbon and alkalinity, helium / tritium / noble gases and radiocarbon. Underway measurements comprised navigation, currents (ADCP), meteorology, and sea surface temperature and salinity. The remainder of the hydrographic section was executed a year later on RRS James Clark Ross, cruise JR239
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