实时交通数据支持下的医疗服务时空可达性分析

针对现有城市医疗服务可达性分析方法未考虑就医偏好,导致测算结果与居民实际感受相差较大的问题,本文提出了一种顾及时间和距离成本偏好的医疗服务时空可达性分析方法,并以武汉市中心城区为例进行了分析。试验结果表明,研究方法充分利用交通路况,兼顾了交通距离和通行时间对就医选择的影响,距离偏好在新方法中作用显著。该方法一方面可以体现不同时刻可达性差异,另一方面又强调了居民就医的时间和距离成本偏好,相比单一的时间或距离成本更具优势,分析结果更符合现实。     

Simulating urban land-use change based on the multi-hierarchal planning–environment interaction process

Urban land-use change is the result of coupling interaction between planning and environment systems. The aim of our study was to construct an effective model to show how the urban land-use changes under the planning–environment interaction system with multi-hierarchy and major function oriented zoning. Combining the Cellular automata (CA) model with logistic regression model, the proposed multi-hierarchal vector CA model (MH-VCA3) was constructed by mining multi-hierarchal land-use transition rules under the planning–environment interaction system. Taking Jiangyin City (China) as an example, we compared the simulated result of the proposed model to those of the well-accepted Logistic CA and traditional multi-level CA models to demonstrate the effectiveness of the consideration of top-down decomposition constraint and bottom-up updating. Furthermore, by simulating the land-use changes under different population regionalization scenarios, we found that in order to form the spatial pattern of “agglomeration in the north and ecology in the south,” the planned population growth at the global hierarchal level should be allocated to the district units according to the law of Central district > Chengxi district > Chengdong district > Chengnan district > Chengdongnan district. The proposed model is expected to provide scientific support for the formulation of urban planning schemes in the future.     

Dynamics of the eco-environmental quality in response to land use changes in rapidly urbanizing areas: A case study of Wuhan,China from 2000 to 2018

Journal of Geographical Sciences - The dramatic land use changes that occur in rapidly urbanized areas are important inducement to changes in the eco-environmental quality. Investigating urban land...     

UPLC-MS metabolomics provides insights into the differences between black- and white-shelled Pacific oysters Crassostrea gigas

Journal of Oceanology and Limnology - A variety of shell colors are one of the most fundamental characteristics of molluscs, which have importantly ecological and economic significance. The Pacific...     

Precipitation type estimation and validation in China

The results from three methods aimed at improving precipitation type(e.g., rain, sleet, and snow) estimation are presented and compared in this paper. The methods include the threshold air temperature(AT), threshold wet bulb temperature(WBT) and Koistinen and Saltikoff(KSS) methods.Dot graphs are plotted to acquire the threshold air temperature or the threshold wet bulb temperature using daily averaged air temperature, wet bulb temperature and precipitation data at 643 stations from 1961 to 1979(precipitation types are not labeled in the database from 1980 to present) in China. The results indicate that the threshold AT or WBT methods are not able to differentiate rain, sleet and snow in the most regions in China; sleet is difficult to differentiate from other precipitation types based on the two threshold methods. Therefore, one threshold AT and WBT method was used in this study to differentiate rain and snow. Based on GaussianKriging interpolation of threshold air temperature(T0and wet bulb temperature(Tw), the T0 and Tw contour lines and contour surfaces are calculated for China.Finally, a comparison between the KSS, AT and WBT methods are provided in which the KSS method is calculated based on air temperature and relative humidity. The results suggest that the KSS method is more appropriate for water phase estimation than are the other methods; the maximum precision for rain and snow is 99% and 94%, respectively. The AT method performs better than the WBT method when the critical air temperature is 2°C.     

Mapping daily temperature and precipitation in the Qilian Mountains of northwest China

Daily meteorological data are the critical inputs for distributed hydrological and ecological models. This study modified mountain microclimate simulation model （MTCLIM） with the data from 19 weather stations, and compared and validated two methods （the MTCLIM and the modified MTCLIM） in the Qilian Mountains of Northwest China to estimate daily temperature （i.e., maximum temperature, minimum temperature） and precipitation at six weather stations from i January 2000 to 31December 2009. The algorithm of temperature in modified MTCLIM was improved by constructing the daily linear regression relationship between temperature and elevation, aspect and location information. There are two steps to modify the MTCLIM to predict daily precipitation： firstly, the linear regression relationship was built between annual average precipitation and elevation, location, and vegetation index; secondly, the distance weight for measuring the contribution of each weather station on target point was improved by average wind direction during the rainy season. Several regression analysis and goodness-of-fit indices （i.e., Pearson＇s correlation coefficient, coefficient of determination, mean absolute error, root-mean-square error and modelingefficiency） were used to validate these estimated values. The result showed that the modified MTCLIM had a better performance than the MTCLIM. Therefore, the modified MTCLIM was used to map daily meteorological data in the study area from 2000 to 2009. These results were validated using weather stations with short time data and the predicted accuracy was acceptable. The meteorological data mapped could become inputs for distributed hydrological and ecological models applied in the Qilian Mountains.     

禹城市城区东营组热储地热资源赋存特征研究

山东省禹城市城区在大地构造上属于华北陆块、华北拗陷区、济阳坳陷区、惠民潜断陷、临邑凹陷南部。通过已有钻探资料及近年的勘查项目研究成果,对禹城市城区东营组热储的地热资源的地质背景、水文地质特征、地热流体化学特征等进行了综合研究分析,认为禹城市城区东营组热储属于层控型低温地热田,地下热水矿化度较大,成因主要为大气降水。     

A new MODIS daffy cloud free snow cover mapping algorithm on the Tibetan Plateau

Because of similar reflective characteristics of snow and cloud, the weather status seriously affects snow monitoring using optical remote sensing data. Cloud amount analysis during 2010 to 2011 snow seasons shows that cloud cover is the major limitation for snow cover monitoring using MOD10A1 and MYD10A1. By use of MODIS daily snow cover products and AMSR-E snow wa- ter equivalent products （SWE）, several cloud elimination methods were integrated to produce a new daily cloud flee snow cover product, and information of snow depth from 85 climate stations in Tibetan Plateau area （TP） were used to validate the accuracy of the new composite snow cover product. The results indicate that snow classification accuracy of the new daily snow cover product reaches 91.7% when snow depth is over 3 cm. This suggests that the new daily snow cover mapping algorithm is suitable for monitoring snow cover dynamic changes in TP.     

CLM4.0模式对中国区域土壤湿度的数值模拟及评估研究

本文利用普林斯顿大学全球大气强迫场资料,驱动公用陆面过程模式（Community Land Model version 4.0,CLM4.0）模拟了中国区域1961～2010年土壤湿度的时空变化。将模拟结果与观测结果、美国国家环境预报中心再分析数据（National Centers for Environmental Prediction Reanalysis,NCEP）和高级微波扫描辐射计（Advanced Microwave Scanning Radiometer-EOS,AMSR-E）反演的土壤湿度进行了对比分析,结果表明CLM4.0模拟结果可以反映出中国区域观测土壤湿度的空间分布和时空变化特征,但东北、江淮和河套三个地区模拟值相对于观测值在各层次均系统性偏大。模拟与NCEP再分析土壤湿度的空间分布基本一致,与AMSR-E的反演值在35°N以北的分布也基本一致;从1961～2010年土壤湿度模拟结果分析得出,各层土壤湿度空间分布从西北向东南增加。低值区主要分布在新疆、青海、甘肃和内蒙古西部地区。东北平原、江淮地区和长江流域为高值区。土壤湿度数值总体上从浅层向深层增加。不同深度土壤湿度变化趋势基本相同。除新疆西部和东北部分地区外,土壤湿度在35°N以北以减少趋势为主,30°N以南的长江流域、华南及西南地区以增加为主。在全球气候变暖的背景下,CLM4.0模拟的夏季土壤湿度在不同程度上响应了降水的变化。中国典型干旱区和半干旱区土壤湿度减小,湿润区增加。其中湿润区土壤湿度对降水的响应最为显著,其次是半干旱区和干旱区。     

上海地区基于静力触探的液化判别分析

上海地区(及其他软土地区)以静探触探作为岩土工程勘察的主要原位测试手段,积累了大量的工程数据,其结果稳定可靠,重现性好,具客观性。采用上海地区静探液化判别方法,对收集的大量资料进行统计分析,以期通过静探Ps值快速、简单地作出地基土是否液化的初步判断,有效指导勘察设计工作。