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F. Giovannelli C. Bartolini A. Guarnieri A. Piccioni M. Burger E. L. Van Dessel V. G. Kurt E. K. Sheffer D. De Martino R. Waters I. Gonzalez Martinez-Pais Yu. N. Gnedin V. M. Larionov N. I. Shakovskaya 《Astrophysics and Space Science》1990,169(1-2):139-145
Within the framework of a very long multifrequency campaign of coordinated, and very often simultaneous, observations of the transient X-ray/Be system A 0535+26/HDE 245770, we present a summary of this large collection of data taken with IUE and ASTRON satellites as well as with many ground-based telescopes in optical and IR regions.In this paper we emphasize the study of the physics and dynamics of the mass transfer at periastron and subsequent X-ray flaring, which is a typical problem of the X-ray/Be binary system class.Paper presented at the 11th European Regional Astronomical Meetings of the IAU on New Windows to the Universe, held 3–8 July, 1989, Tenerife, Canary Islands, Spain. 相似文献
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Eric J. Bakker Henny J. G. L. M. Lamers L. B. F. M. Waters Ton Schoenmaker 《Astrophysics and Space Science》1995,231(1-2):335-338
We present preliminary results obtained with the European Observation Network. This network consists of 9 observatories in the Czech Republic, Germany and Bulgaria and has been involved in the BACODINE activities since April 1, 1994. We also discuss related problems such as the background of unknown variable stars and suggest a strategy for work in this area. 相似文献
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Thomas S. Harmon Joseph M. Smoak Matthew N. Waters Christian J. Sanders 《Environmental Earth Sciences》2014,71(10):4387-4395
Anthropogenic impacts to island systems can have deleterious effects on coastal aquatic ecosystems. These effects can alter water quality, primary production as well as habitat. Land development often fragments hydrologic connectivity within aquatic ecosystems forcing alterations in nutrient transport and increases the potential for eutrophication. Dove Sound, a tidal lagoon located in the Upper Florida Keys on Key Largo, has been subjected to anthropogenic influences of land development during the last century. To investigate these influences a short sediment core was collected from within Dove Sound and investigated using 210Pb dating, stable isotopes of carbon and nitrogen, and sedimentary pigments. Results indicated that Dove Sound has undergone eutrophication and the primary producer community structure has shifted from dominantly macrophytic to a system that supports substantial algal production. While septic waste was a possible source for eutrophication, low δ15N did not support this conclusion. However, the timing of the shifts in Dove Sound along with indicators of anoxia leads to the conclusion that fragmentation caused by the construction of a railroad was the root cause. The hydrologic fragmentation reduced the flushing rates, thereby enhancing anoxic conditions in the system and increasing the internal nutrient loading. 相似文献
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Emergency services personnel face risks and uncertainty as they respond to natural and anthropogenic events. Their primary goal is to minimize the loss of life and property, especially in neighborhoods with high population densities, where response time is of great importance. In recent years, mobile phones have become a primary communication device during emergencies. The portability of cell phones and ease of information storage and dissemination has enabled effective implementation of cell phones by first responders and one of the most viable means of communication with the population. Using cellular location data during evacuation planning and response also provides increased awareness to emergency personnel. This article introduces a multi‐objective, multi‐criteria approach to determining optimum evacuation routes in an urban setting. The first objective is to calculate evacuation routes for individual cell phone locations, minimizing the time it would take for a sample population to evacuate to designated safe zones based on both distance and congestion criteria. The second objective is to maximize coverage of individual cell phone locations, using the criteria of underlying geographic features, distance and congestion. In summary, this article presents a network‐based methodology for providing additional analytic support to emergency services personnel for evacuation planning. 相似文献
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D. Robbins J. Waters P. Zimmermann R. Jarnot J. Hardy H. Pickett S. Pollitt W. Traub K. Chance N. Louisnard W. Evans J. Kerr 《Journal of Atmospheric Chemistry》1990,10(2):181-218
Measurements of the Balloon Intercomparison Campaign (BIC), conducted during fall, 1982 (BIC-1) and summer, 1983 (BIC-2), are reported. Results of five remote and two in situ techniques agree (with a few exceptions) within 95% confidence level uncertainties and generally within 15% above 20 km. Weighted mean profiles, which best represent conditions during the capaign, are used as a comparison standard. Accuracies of experiments indicated by BIC generally confirm estimated uncertainites for ECC sondes, UV photometry, and microwave emission experiments, are somewhat better for far IR emission and IR absorption experiments, and are somewhat worse for IR emission and solar UV absorption experiments. The large collection of BIC measurements confirms a problem reported earlier with current theoretical modeling of ozone near 40 km where transport is negligible and the chemistry is believed to be simpler. 相似文献
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C. J. Warren M. P. Searle R. R. Parrish D. J. Waters 《Contributions to Mineralogy and Petrology》2007,154(1):115-118