泛长三角地区大型主题公园时空分布初步研究     

曹超轶  卢松  杨仲元 《云南地理环境研究》2011,23(5):42-49

作为世界旅游组织确定的未来旅游业发展三大趋势之一的主题公园,近年来以极为迅猛的速度发展,而作为主题公园相对较为集中的泛长三角地区,其发展速度和规模尤为突出。选取上海市、江苏省、浙江省和安徽省,即以泛长江三角洲地区为研究对象,从时间和空间两个维度上对其范围内大型主题公园的分布特征进行分析,总结出泛长三角大型主题公园的发展阶段、空间分布聚集特征明显以及影响分布的5个因素（经济发展因素、区位因素、产业融合因素、创新因素和城市发展因素）等。最后对时空分布进行总结并提出未来需要加强研究的若干方面。  相似文献   

软件产业发展的经济地理学分析     

毕秀晶  汪明峰  宁越敏 《地理科学进展》2011,30(6):658-669

20世纪90年代以来,全球软件产业迅速发展,成为众多国家和地区信息服务业的核心内容.软件服务外包在全球范围内兴起,软件产业全球生产网络日益复杂.软件产业不断成为政府以及学者们研究的新热点,经济地理学视角的软件产业研究也不断涌现,但研究对象主要以发达国家以及印度、巴西等少数新兴软件国家为主,对中国软件产业的经济地理学研究...  相似文献   

MODELING THE SPORADIC METEOROID BACKGROUND CLOUD     

V. Dikarev  E. Grün  J. Baggaley  D. Galligan  M. Landgraf  R. Jehn 《Earth, Moon, and Planets》2004,95(1-4):109-122

The orbital distributions of dust particles in interplanetary space are revised in the ESA meteoroid model to incorporate more observational data and to comply with the constraints due to the long-term particle dynamics under the planetary gravity and Poynting–Robertson effect. Infrared observations of the zodiacal cloud by the COBE Earth-bound observatory, flux measurements by the dust detectors on board Galileo and Ulysses spacecraft, and the crater size distributions on lunar rock samples retrieved by the Apollo missions are fused into a single model. Within the model, the orbital distributions are expanded into a sum of contributions due to a number of known sources, including the asteroid belt with the emphasis on the prominent families Themis, Koronis, Eos and Veritas, as well as comets on Jupiter-encountering orbits. An attempt to incorporate the meteor orbit database acquired by the Advanced Meteor Orbit Radar at Christchurch is also discussed. Work was done during D. Galligan’s stay at the University of Canterbury.  相似文献   

Comparative study of the moment and graphic size parameters of the sediments of the western continental shelf of India     

N. H. Hashimi 《Mathematical Geology》1981,13(4):291-301

A comparative study of the moment and graphic size parameters was undertaken on about two hundred surficial sediment samples varying from sand to clay sizes from the western continental shelf of India. The studies reveal that the mean size and standard deviation may be calculated either by the moment method or by graphic methods (Inman; Folk and Ward) without any significant differences, as the methods are highly correlated. Moment and graphic skewness show less comparability than the mean size and standard deviation. The moment and graphic kurtosis estimate different properties and are not comparable.  相似文献   

金沙江流域实际蒸散发遥感重建及时空特征分析          下载免费PDF全文

张珂  鞠艳  李致家 《水科学进展》2021,32(2):182-191

通过构建基于重力卫星的实际蒸散发重建方法来获取高精度的实际蒸散发信息,为研究气候变化下的水循环规律提供关键信息。利用GLDAS陆面模式同化数据对GRACE重力卫星水储量观测数据进行空间降尺度,通过水量平衡法,重建了金沙江流域2002-2016年的子流域尺度实际蒸散发月序列。结果表明:①基于重力卫星观测与水量平衡方法重建的实际蒸散发（ET_Recon）与ET_PLSH、ET_Jung和ET_MODIS3种遥感反演产品相比有较高的可靠性,其中与ET_PLSH的相关性最高（r=0.82）,与ET_Jung的平均差和均方根差最小。②研究区年均实际蒸散发为410.8 mm/a,空间分布上由西北向东南递增,年际变化上呈增加趋势。③季节尺度上,实际蒸散发夏季最高,呈逐年增加趋势;冬季最低,波动较平稳。  相似文献   

Simulating regional grain yield distributions to support agricultural drought risk assessment     

《Applied geography (Sevenoaks, England)》2015

Most food insecure countries do not have long-term records of either agricultural drought or the impacts of agricultural drought on food security. This lack of data impedes famine early warning and crop insurance programs. One recent paper addresses this issue by using resampled rainfall data, a basic crop yield model, and linear regression to simulate distributions of grain yield. We expand on this process by incorporating flexible regression models and defining a set of criteria to test model performance. We also examine how well a model fit on national data can emulate yield distributions at regions within a country. We find that models with spatially varying coefficients are better able to simulate distributions than basic linear regression models. Generalized additive models also perform well but do not offer substantial improvement over varying coefficient models. We also find that simulated yield distributions are most accurate in higher producing regions that have lower within region diversity of yields.  相似文献   

Wind wave characteristics and engineering environment of the South China Sea     

Zhifeng Wang  Liangming Zhou  Sheng Dong  Lunyu Wu  Zhanbin Li  Lin Mou  Aifang Wang 《中国海洋大学学报(英文版)》2014,13(6):893-900

Wave simulation was conducted for the period 1976 to 2005 in the South China Sea (SCS) using the wave model, WAVEWATCH-III. Wave characteristics and engineering environment were studied in the region. The wind input data are from the objective reanalysis wind datasets, which assimilate meteorological data from several sources. Comparisons of significant wave heights between simulation and TOPEX/Poseidon altimeter and buoy data show a good agreement in general. By statistical analysis, the wave characteristics, such as significant wave heights, dominant wave directions, and their seasonal variations, were discussed. The largest significant wave heights are found in winter and the smallest in spring. The annual mean dominant wave direction is northeast (NE) along the southwest (SW)-NE axis, east northeast in the northwest (NW) part of SCS, and north northeast in the southeast (SE) part of SCS. The joint distributions of wave heights and wave periods (directions) were studied. The results show a single peak pattern for joint significant wave heights and periods, and a double peak pattern for joint significant wave heights and mean directions. Furthermore, the main wave extreme parameters and directional extreme values, particularly for the 100-year return period, were also investigated. The main extreme values of significant wave heights are larger in the northern part of SCS than in the southern part, with the maximum value occurring to the southeast of Hainan Island. The direction of large directional extreme H _s values is focus in E in the northern and middle sea areas of SCS, while the direction of those is focus in N in the southeast sea areas of SCS.  相似文献   

Evolution of the spatial and temporal characteristics of the isotope hydrology of a montane river basin     

M. Speed  D. Tetzlaff  M. Hrachowitz  C. Soulsby 《水文科学杂志》2013,58(3):426-442

Abstract

Precipitation and streamwater were analysed weekly for δ¹⁸O in seven tributaries and five main stem sites of a 2100 km² catchment; >60% of it is upland in character. Precipitation δ¹⁸O followed seasonal patterns ranging from –20‰ in winter to –4‰ in summer. Seasonality was also evident in stream waters, though much more damped. Mean transit times (MTTs) were estimated using δ¹⁸O input–output relationships in a convolution integral with a gamma distribution. The MTTs were relatively similar (528–830 days): tributaries exhibited a greater range, being shorter in catchments with montane topography and hydrologically responsive soils, and longer where catchments have significant water storage. Along the main stem, MTTs increased modestly from 621 to 741 days. This indicates that montane headwaters are the dominant sources of runoff along the main stem of the river system. Models suggest that around 10% of runoff has transit times of less than two weeks during higher flows whilst older (>10-year old) water sustains low flows contributing around 5% of runoff.

Citation Speed, M., Tetzlaff, D., Hrachowitz, M. & Soulsby, C. (2011) Evolution of the spatial and temporal characteristics of the isotope hydrology of a montane river basin. Hydrol. Sci. J. 56(3), 426–442  相似文献   

Finding the most appropriate precipitation probability distribution for stochastic weather generation and hydrological modelling in Nordic watersheds   总被引：2，自引：0，他引：2  

Zhi Li  Francois Brissette  Jie Chen 《水文研究》2013,27(25):3718-3729

Six precipitation probability distributions (exponential, Gamma, Weibull, skewed normal, mixed exponential and hybrid exponential/Pareto distributions) are evaluated on their ability to reproduce the statistics of the original observed time series. Each probability distribution is also indirectly assessed by looking at its ability to reproduce key hydrological variables after being used as inputs to a lumped hydrological model. Data from 24 weather stations and two watersheds (Chute‐du‐Diable and Yamaska watersheds) in the province of Quebec (Canada) were used for this assessment. Various indices or statistics, such as the mean, variance, frequency distribution and extreme values are used to quantify the performance in simulating the precipitation and discharge. Performance in reproducing key statistics of the precipitation time series is well correlated to the number of parameters of the distribution function, and the three‐parameter precipitation models outperform the other models, with the mixed exponential distribution being the best at simulating daily precipitation. The advantage of using more complex precipitation distributions is not as clear‐cut when the simulated time series are used to drive a hydrological model. Although the advantage of using functions with more parameters is not nearly as obvious, the mixed exponential distribution appears nonetheless as the best candidate for hydrological modelling. The implications of choosing a distribution function with respect to hydrological modelling and climate change impact studies are also discussed. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

Linear versus non-linear earthquake location and seismogenic fault detection in the southern Tyrrhenian Sea, Italy     

D. Presti  B. Orecchio  G. Falcone  G. Neri 《Geophysical Journal International》2008,172(2):607-618

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