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Seasonal snow in New Zealand is likely to be subject to substantial change due to the impacts of climate change. These changes will have wide ranging impacts on the New Zealand's economy through the energy, agricultural and tourism sectors. In this paper, we assess the impact of climate change, at a micro-scale for a selection of ski area locations in New Zealand. Where available, we have used current observations of snow depth to calibrate the snow model output for the current climate. We consider the change in the number of days with snow depths exceeding 0.30?m, ??snow-days??, at each of these locations for the 2030?C2049 (mid-point reference 2040) and 2080?C2099 (mid-point reference 2090) time periods, for the three different emission scenarios (B1, A1B and A1FI). These future scenarios are compared to simulations of current, 1980?C1999 (mid-point reference 1990), number of snow-days at these locations. We consider both an average year in each 20-year period, as well as a ??worst-case?? year. At each ski area, we consider an upper and lower elevation site. Depending on the elevation and location of the specific site, our analysis shows that there will be a reduction in the number of snow-days in nearly all of the future scenarios and time periods. When we consider a worst-case or minimum snow year in the 1990s, the number of snow-days at each site ranges from 0 to 229, while by the 2040s, it ranges from 0 to 187 (B1), 0 to 183 (A1B) and 0 to 176 (A1FI). By the 2090s the number of snow-days ranges from 0 to 155 (B1), 0 to 90 (A1B) and 0 to 74 (A1FI). We also simulate the hourly future climate for the 2040s and 2090s, for the A1FI scenario, to enable calculations of the potential available time for snowmaking in these two future time periods. We use simulated temperatures and humidity to calculate the total potential snowmaking hours in the future climates. For the snowmaking analysis, only a worst-case year in each time period, rather than an average year, was used to assess the snowmaking potential. This was done to ensure consistency with snowmaking design practices. At all sites, for the A1FI emissions scenario and for both future time periods, a reduction in potential snowmaking hours is observed. By the 2040s, there is only 82 to 53?%, and by the 2090s, there is only 59 to 17?% of the snowmaking time as compared to the 1990s in a worst-case year. Despite this reduction in snowmaking opportunity, snowmaking was still possible at all sites examined. Furthermore, the amount of snow which could be made was sufficient to reinstate the number of snow-days to the lesser of either that observed in the 1990s for each site or to exceed 100?days. While our snowmaking analysis has some limitations, such as neglecting calculation of melt in the man-made snow component, this study highlights the importance of considering adaptation options such as snowmaking for a more complete impact assessment.  相似文献   
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--The electromagnetic (EM) coupling effect in induced polarization (IP) data is an important problem. In many works it has been computed only considering homogeneous or layered earth models with discretely uniform conductivity. In this study, an algorithm has been developed to compute the EM coupling effect in IP data measured on the earth, whose conductivity varies (increases or decreases) exponentially with depth. The EM coupling effects for Percent Frequency Effect (PFE) and phase data are computed for a dipole-dipole array with different separations, however the method can be applied to any electrode array. The results obtained for the cases of increasing and decreasing conductivity as a function of depth indicate that the EM coupling effect strongly depends on the subsurface resistivity and the dipole length. Here an "exponential" earth model is considered to remove EM coupling from the IP data in frequency and phase domain. For this purpose, first, the region of pseudo-section is divided into segments, and within each segment a typical average apparent resistivity (a) curve is constructed. An exponential conductivity model is fitted to average a data. The conductivity model is then used to compute EM responses. Next the data are corrected for the EM coupling contribution. This decoupling process is applied to field data from a galenite-pyrite mineralization area at the Dolluk site, in western Turkey. The results from the decoupling method developed here are compared with other techniques.  相似文献   
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In this study a new grated inlet is proposed for small roads which do not have storm water collection systems. A setup was designed and constructed in the laboratory conditions to calibrate the grated inlet. The inlet is suggested to be installed at the end of the road where the road itself joins to another road or to a street. Thus, newly installed inlet will collaborate with existing storm water collecting system of the main road. Inlet structure covered by slots is installed across a 0.90-m wide flume which will act as a small road. The slots are longitudinal and parallel to the flow direction in order to curtail clogging. It is a tilting flume and both subcritical and supercritical flow regimes can be observed. The intercepted flow by the inlet is measured and the efficiency of the inlet is obtained in terms of longitudinal slope and the Froude number. It is observed that the grate efficiency gets higher as the longitudinal slope approaches to horizontal. Further the grate efficiency also depends on the total flow through the channel. As flow increases in the channel, the efficiency of the grate increases within the limit of the inlet or discharge channels capacity.  相似文献   
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The Menderes Massif, exposed in western Anatolia, is a metamorphic complex cropping out in the Alpine orogenic belt. The metamorphic rock succession of the Massif is made up of a Precambrian basement and overlying Paleozoic-early Tertiary cover series. The Pan-African basement is composed of late Proterozoic metasedimentary rocks consisting of partially migmatized paragneisses and conformably overlying medium- to high-grade mica schists, intruded by orthogneisses and metagabbros. Along the southern flank of the southern submassif, we recognized well-preserved primary contact relationship between biotite and leucocratic tourmaline orthogneisses and country rocks as the orthogneisses represent numerous large plutons, stocks and vein rocks intruded into a basement of garnet mica schists. Based on the radiometric data, the primary deposition age of the precursors of the country rocks, garnet mica schist, can be constrained between 600 and 550?Ma (latest Neoproterozoic). The North Africa–Arabian-Nubian Shield in the Mozambique Belt can be suggested as the possible provenance of these metaclastics. The intrusion ages of the leucocratic tourmaline orthogneisses and biotite orthogneisses were dated at 550–540?Ma (latest Neoproterozoic–earliest Cambrian) by zircon U/Pb and Pb/Pb geochronology. These granitoids represent the products of the widespread Pan-African acidic magmatic activity, which can be attributed to the closure of the Mozambique Ocean during the final collision of East and West Gondwana. Detrital zircon ages at about 550?Ma in the Paleozoic muscovite-quartz schists show that these Pan-African granitoids in the basement form the source rocks of the cover series of the Menderes Massif.  相似文献   
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We investigate the possibility to diagnose the ??-distributions from the EUV spectra observed by the Hinode/EIS spectrometer. Observable lines of the most abundant elements except Fe are considered. Synthetic spectra for the ??-distributions with ??=2??C?10 and the Maxwellian distribution were calculated for a range of temperatures and electron densities. We find that only a small number of O, S, Ca, and Ni line ratios are sensitive to???. A?list of the best diagnostic options using transition region and coronal lines is provided. Usually, the line ratios sensitive to ?? are also sensitive to electron density. Weak O?iv lines are a notable exception. These lines offer greatest sensitivity to ?? from all the lines observed by Hinode/EIS. Density diagnostics using lines of the non-Fe elements is discussed and the influence of ?? on the diagnostics of electron density is presented. The density diagnostics using these non-Fe EIS lines are strongly affected by both known and unknown blends. Therefore, we performed the density diagnostics using the Fe?xii??C?xiv lines. Subsequently, these proposed diagnostic methods for ??-distributions are tested using the spectral atlas obtained by Brown et?al. (Astrophys. J. Suppl. 176, 511, 2008). These data do not provide conclusive evidence for the presence of ??-distributions due to possible plasma multitermality, a low observed signal-to-noise ratio, and unremovable or unknown blends.  相似文献   
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A nonlinear hysteretic model for the response and local damage analyses of reinforced concrete shear frames subject to earthquake excitation is proposed, and, the model is applied to analyse midbroken reinforced concrete (RC) structures due to earthquake loads. Each storey of the shear frame is represented by a Clough and Johnston hysteretic oscillator with degrading elastic fraction of the restoring force. The local damage is numerically quantified in the domain [0,1] using the maximum softening damage indicators which are defined in closed form based on the variation of the eigenfrequency of the local oscillators due to the local stiffness and strength deterioration. The proposed method of response and damage analyses is illustrated using a sample 5 storey shear frame with a weak third storey in stiffness and/or strength subject to sinusoidal and simulated earthquake excitations for which the horizontal component of the ground motion is modeled as a stationary Gaussian stochastic process with Kanai-Tajimi spectrum, multiplied by an envelope function.  相似文献   
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A suite of synthetic titanomagnetites of composition Fe2.4?δAlδTi0.6O4 and Fe2.6?δAlδTi0.4O4 (δ = 0, 0.1 and 0.2 in both cases) have been prepared by a method of partial self-buffering and pulverized in a ball mill to particle size of about 200–500 Å. Magnetic hysteresis parameters-saturation and remanent magnetizations and coercive force were measured between room temperature and the Curie temperatures and other parameters-X-ray cell edge, initial susceptibility and coercive force of remanence were determined at room temperature. The intrinsic magnetic “hardness” increases with increasing content of Al3+ and Ti4+, both probably corresponding to an increase in the concentration of Fe2+ ions on the tetrahedral sites of the spinel structure. The room-temperature hysteresis properties were compared with those resulting from monodomain models for the work done to magnetically saturate an assemblage of grains and the approach to saturation, and the separate contributions from coexisting anisotropies of cubic and uniaxial symmetries (assumed present) inferred. The cubic anisotropy energy constants so derived are larger than those determined from multidomain single crystals. The derived cubic constants are also larger than the derived uniaxial anisotropy constants. The latter, however, dominate the behaviour (e.g., coercive force) because of the lower symmetry. The materials appear to be entirely in the stable monodomain state at room temperature.  相似文献   
10.
A suite of synthetic titanomagnetites were prepared with compositions Fe2.6?δTi0.4AlδO4 and Fe2.4?δTi0.6AlδO4 (δ = 0, 0.1, 0.2 in both cases). Ball-milling of the synthesized samples produced material in the magnetic monodomain state as indicated by hysteresis loops and the Lowrie-Fuller test. The coercive force of the specimens depends on the Al concentration and lies in the range 1–2 kOe. The TRM induced in the samples is correspondingly “hard”. The low-field (0–1 Oe) TRM acquisition curve is linear. The higher field TRM-H curve is not in agreement with either monodomain or two-domain theoretical models.  相似文献   
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