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181.
This paper explores the links between a strategic policy, urban consolidation, and house prices by examining the changes in
the mix of housing and in house price for the period 1991–2004. We contend that urban consolidation could be seen as a source
of additional supply, (which might be expected to be felt in lower prices and so contribute to a local policy objective) but
also as a stimulus to demand (by developers who could bid up the price of lots where it was understood more housing could
be built). Analyses were carried out at the metropolitan and sub-regional scales using correlation tests. The research finds
very weak statistical connections, and concludes that this policy has not been associated with price changes. 相似文献
182.
Yousif O. Mohammad 《Arabian Journal of Geosciences》2013,6(2):505-518
The Penjwin meta-peridotite rock represents one of the five main metamorphosed ultramafic bodies in Kurdistan region, Northwest Zagros Thrust Zone. It underwent at least two successively low-retrograde metamorphic events with one progressive one which all modified the original mineralogy and texture of primary dunite and harzburgite. The primary upper mantle mineral assemblage olivine?+?orthopyroxene?+?chromian spinel is replaced by olivine?+?tremolite–actiolite?+?anthopylite?+?talc?+?ferichromite?+?Cr-chlorite assemblage of amphibolite facies. The further retrograde metamorphic amphibolite facies assemblage is replaced by lizardite–chrysotile?+?Cr-chlorite?+?syn-serpentinization Cr-magnetite of lower greenschist facies. Later at the main Zagros thrust fault, low greenschist facies underwent progressive metamorphism due to the local effect of shear stress as a result of the exhumation and obduction of Penjwin ophiolite suite over Merga Red bed series during Tertiary. Lizardite–chrysotile transformed to antigorite and producing antigorite?+?carbonate?+?syn-serpentinization Cr-magnetite?+?Cr-chlorite assemblage of upper greenschist facies. Chromian spinel is concentrically zoned as a result of multi-stages retrogressive metamorphic events, in which the Cr # (Cr/(Cr?+?Al)) increases from core to rim (0.5 to 1). Three zones can be identified from core to rim: The core is primary Al-rich and mantled by ferrichromite of amphibolite facies. The most outer zone of chromian spinel grains is represented by syn-serpentinization Cr-magnetite of greenschist facies. 相似文献
183.
A. M. Zvyagintsev G. Kakadzhanova G. M. Kruchenitskii O. A. Tarasova 《Russian Meteorology and Hydrology》2008,33(3):159-166
Characteristics of periodic variability of surface ozone concentration at 98 western and central European stations participating in the EMEP program for at least 7 (up to 14) years are determined. Daily and hourly model concentrations of surface ozone for each station are given in an analytical form that presents a sum of a constant constituent and basic harmonics that determine ozone concentration variability throughout a year and a day. A 12-month harmonic, whose maximum is observed in the spring period (in Northern Europe it is observed 1 to 2 months earlier than in Southern Europe) dominates in the energy spectrum of seasonal variability of daily mean ozone concentration at most stations. The energy part of higher (6-and 4-month) harmonics is the largest at the stations close to the sea and ocean coasts. Higher harmonics largely influence the time of the ozone extremum formation, shifting it towards the summer, or even forming a second (summer) maximum, whose magnitude at a number of stations (in Italy, Hungary, in the south of Germany, and in some others) exceeds the spring maximum. A 24-hour harmonic dominates in the energy spectrum of daily ozone variability. The maps of a “normal” distribution of surface ozone fields and their standard deviations for different seasons and time of the day have been compiled based on the model characteristics. The “norms” derived can be used to detect anomalies in the temporal trend of the surface ozone and to validate its climate changes. 相似文献
184.
Giant radio galaxies are the most extended radio sources in the universe having the sizes of groups and clusters of galaxies
(about 1 Mpc). Their total number is comparable with the amount of clusters, revealing the Zeldovich-Sunyaev effect, which
may lead to a biased estimation of the angular power spectrum for the ZS effect. To assess a possible contribution to the
power spectrum, we need to collect the data on all the observed giant radio galaxies. We propose an algorithm for the selection
of large sources (sized over 4′) from the NVSS survey catalog, using the parameters of possible components of radio sources,
cataloged as compact objects. As a result of the first stage of our work, we have selected 61 new giant radio galaxy candidates,
of which 35 have a pronounced morphological type FRII, and 26 galaxies—the FRI type. 相似文献
185.
V. I. Mel’nikova N. A. Gileva S. S. Aref’ev V. V. Bykova O. K. Masal’skii 《Izvestiya Physics of the Solid Earth》2012,48(7-8):594-614
The results of investigating the data of stationary and field observations in the epicentral zone of the Kultuk earthquake of August 27, 2008 with M w = 6.3 localized south of Baikal are presented. The seismic activation amounting to 1790 aftershocks with K p ?? 4 (M w ?? 0.9) affected a part of the general fault bounding the southwestern coast of the lake and shallower intrabasin structures. It was established through the cluster analysis that the main shock was located at the periphery of the cloud of the concentrated seismicity component, and three main clusters reflecting a complex character of rupture in the earthquake source were identified in the zone of aftershocks. Owing to a high accuracy of aftershock hypocenters determinations (ERZ ?? 1.2 km), the local character of the seismisity-generating zones was revealed. Based on the method of mapping seismic regime parameters, it was established that zones of reduced fractionality are recognizable in the central part of the source area; in this case, the entire periphery, except for the southeastern direction (where the main shock epicenter is located), is characterized by a high fractionality, which also points to the complex character of the rupture in the source. On the whole, the aftershock sequence under consideration showed the activation of the southwestern flank of the Southern Baikal region, which remained passive for more than one century, and demonstrated destructive features of the Earth??s crust. 相似文献
186.
187.
Danielle C. Sattelberger Joyce M. Kleen Aarin-Conrad Allen Richard O. Flamm 《地理信息系统科学与遥感》2017,54(1):1-19
The largest Florida manatee (Trichechus manatus latirostris) aggregation at a natural warm-water site occurs in Kings Bay, Crystal River, FL. In accordance with the Manatee Recovery Plan, manatee protection areas within Kings Bay have been created by the United States Fish and Wildlife Service (USFWS) and the State of Florida including a year-round refuge designation and seven Federal manatee sanctuaries during the winter manatee season (15 November–31 March). Over the last 30 years, an increase in manatee counts has been observed in Kings Bay which has prompted the need to review existing manatee protection measures. Aerial survey data collected between 1983 and 2012 were used to examine the seasonal change in manatee distribution within Kings Bay to assess the effectiveness of current sanctuary sizes and locations. Regression analysis suggested a significant change in manatee abundance among the winter seasons (p < 0.05). The average winter manatee counts increased by 4.81 animals per year over the 30-year period. Spatially explicit maps using geographic information system (GIS) analysis revealed a strong correlation between high manatee density and artesian springs in Kings Bay during the winter seasons. Highest abundances were identified at three locations: King Spring, Three Sisters Springs, and Magnolia Springs, which coincide with preexisting sanctuary designations. Additional coverage is advocated to support the overflow of manatees outside of sanctuary boundaries. As density patterns were not uniform across summer periods, a consideration of additional boat speed regulations is recommended. 相似文献
188.
FluBiDi is a two-dimensional model created to simulate real events that can take days and months, as well as short events (minutes or hours) and inclusive laboratory tests. To verify the robustness of FluBiDi, it was tested using a previous study with both designed and real digital elevation models. The results highlight good agreement between the models (i.e. Mike Flood, SOBEK, ISIS 2D, and others) tested and FluBiDi (around 90% for a specific instant and 95% for the complete time simulation). In the simulated hydrographs, the discharge peak value, time to peak, and water level results were accurate, reproducing them with an error of less than 5%. The velocity differences observed in a couple of tests in FluBiDi were associated with very short periods of time (seconds). However, FluBiDi is highly accurate for simulating floods under real topographical conditions with differences of around 2 cm when water depth is around 150 cm. The average water depth and velocities are precise, and the model describes with high accuracy the pattern and extent of floods. FluBiDi has the capability to be adjusted to different types of events and only requires limited input data. 相似文献
189.
The results of the high-resolution long-term spectral monitoring of the Herbig Ae star HD 31648 in the regions of emission
Hα line, Na I D resonance lines and OI 7774 lines are presented.
We confirmed the conclusion, made in previous papers, that the spectral variability of the star in the region of Hα line have
a cyclic character. It is manifested itself as the changing of the equivalent width and intensity of Hα line of the time scale
of about 1200d.
It is shown, that the stellar wind is non-homogeneous and consists of several components, which are differed each other by
their velocities. They are observed as in the H line as in Na I D resonance lines. The component’s parameters are changed
during the cycle of stellar activity (in the maximum of activity the velocity and density of the wind are taken the largest
values and then they are gradually decreased).
The investigation of rapid variability of the He I 5876 line on the time scale of a few hours allows find the correlation
between the variability of the blue and the red wings of the line. It points at the connection between the accretion and the
outflows. Such connection, in particularly, is predicted by the modeling of the wind from young stars made in the frame of
the magneto-centrifugal model, the accordance of which for the HD 31648 was shown in the previous papers. In the present work
we confirmed this conclusion on the basis of the new data.
We found the weak variability of the stellar brightness (about 0.2m), which is agree with the spectral variability (the brightness
of the star becomes lower in the maximum of the activity). These changes are well explained by the process of the dust transfer
from CS disk by the stellar wind. This process is likely to be more effective in the maximum of activity.
An analysis of the variability of other spectral lines shows the agreement between the changing of the Hα line, the Na I D
resonance doublet lines and KI 7698 line. The weak connection between the He I 5876 and the Na I D lines is also found. Since
the formation regions of He I 5876 and Na I D lines are essentially different, we can conclude that the phenomena, responsible
for the observed cyclic variability, take place in a spacious region of the CS envelope.
We believe that the most plausible reason of found cyclic variability is the reconstruction of the inner structure of the
CS gas envelope, caused by the presence around the star a low mass companion or planet.
__________
Translated from Astrofizika, Vol. 50, No. 4, pp. 565–588 (November 2007). 相似文献
190.
Strack OD 《Ground water》2006,44(1):91-98
We deal in this paper with an ongoing development of the analytic element method. We present in outline new analytic line elements that are suitable to model general flow fields, i.e., flow fields that possess a continuously varying areal inflow or outflow. These elements are constructed specifically to model the leakage through leaky layers that separate aquifers in leaky systems and to model transient effects. The leakage or release from storage underneath linear features is modeled precisely by the new elements; the singularity in leakage is matched exactly by the approximate solution. Applications are given for a problem involving leakage and for a case of transient flow. We note that the analytic elements can be used also to reproduce the effect of continuously varying aquifer properties, e.g., the hydraulic conductivity or the elevation of the base of the aquifer. In the latter case, the elements would reproduce the rotation of the flow field caused by the variation in properties, rather than the divergence as for the case of leakage. 相似文献