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11.
Finding accurate methods for estimating and mapping land prices at the macro-scale based on publicly accessible and low-cost spatial data is an essential step in producing a meaningful reference for regional planners.This asset would assist them in making economically justified decisions in favor of key investors for development projects and post-disaster recovery efforts.Since 2005,the Ministry of Land,Infrastructure,and Transport of Japan has made land price data open to the public in the form of observations at dispersed locations.Although this data is useful,it does not provide complete information at every site for all market participants.Therefore,estimating and mapping land prices based on sound statistical theories is required.This paper presents a comparative study of spatial prediction of land prices in 2015 in Fukushima prefecture based on geostatistical methods and machine learning algorithms.Land use,elevation,and socioeconomic factors,including population density and distance to railway stations,were used for modeling.Results show the superiority of the random forest algorithm.Overall,land prices are distributed unevenly across the prefecture with the most expensive land located in the western region characterized by flat topography and the availability of well-connected and highly dense economic hotspots.  相似文献   
12.
浙江丽水地区旅游资源区划与开发   总被引:1,自引:1,他引:0  
论述了浙江丽水地区旅游资源的特点和区域分布特征,提出根据资源特点、抓住地方特色进行旅游开发.  相似文献   
13.
日本兵库县南部地震调查与中国唐山大地震的比较   总被引:1,自引:0,他引:1  
叙述了1995年1月日本兵库县南部地震的强地面运动特征,并与1976年中国唐山地震的地面运动特征进行了对比,讨论了日本地震后次生灾害——火灾的残酷性,并分析了该次地震的前兆现象  相似文献   
14.
本文对地—县计算机网络系统的结构及功能、地级业务系统局域网的软硬件环境、地—县微机终端系统的通信方式及软硬件环境等问题进行了介绍和探讨,并提出一些建议  相似文献   
15.
Xilin Liu  Junzhong Lei 《Geomorphology》2003,52(3-4):181-191
Based on the definitions of the United Nations, the assessment of risk involves the evaluation of both hazard and vulnerability. This forms the basis of a generalized assessment model of debris flow risk. Hazard is a measure of the threatening degree of an extreme event and is expressed theoretically as a function of event magnitude and frequency of occurrence. Mathematically, it is the definite integral area under the magnitude–frequency curve. Based on the need for a model applicable in regions that lack data, a new method that incorporates theoretical concepts with empirical analysis is presented to calculate the regional hazardousness of debris flows. Debris flow hazard can be estimated from gully density, mean annual rainfall and percentage of cultivated land on steep slope. Vulnerability is defined as the potential total maximum losses due to a potential damaging phenomenon for a specified area and during a reference period. On a regional scale, it is dependent on the fixed assets, gross domestic product, land resources and population density, as well as age, education and wealth of the inhabitants. A nonlinear, power-function model to compute the vulnerability degree is presented. An application of the proposed method to Zhaotong prefecture of Yunnan province, SW China, provides high accuracy and reasonable risk estimates. The highest risk of debris flow is in Zhaotong county with a value of 0.48; the lowest risk of debris flow is in Yanjin county with a value of 0.16. The other counties have debris flow risks ranging from 0.22 to 0.46. This provides an approach for assessing the regional debris flow risk and a basis for the formulation of a regional risk management policy in Zhaotong prefecture.  相似文献   
16.
It has been often observed that black mud recently formed and accumulated in slip planes that are closely associated with a progressing landslide in Japan. Mössbauer spectroscopy revealed that the composition of Fe species in the sliding mud is different from those in the debris rock and bedrock. The sliding mud contains more ferrous iron species, which indicates a relatively stronger reducing condition within the sliding zone than within the host rocks. In addition, the composition of Fe species, the total Fe and the volume of sliding mud also change with landslide development. Therefore, detailed Fe speciation in landslide profiles can be a useful approach to understanding the progress of a landslide and may also predict future sliding as well.  相似文献   
17.
李祥妹 《山地学报》2002,20(6):701-705
畜牧业生态系统功能评价是进行草地系统保护与管理、防治草地退化的前提,是畜牧业系统优化和持续发展的根本。为此,以西藏自治区那曲地区草地为研究对象,通过设立评价指标,建立多因子评价模式,采用三角分析法对区域内畜牧业生态系统的社会、经济、生态功能进行综合评价。为区域畜牧业未来发展提供依据。  相似文献   
18.
赵逸才 《地理研究》2019,38(8):2058-2067
市管县体制确立以来,地级市成为了中国统县政区的主体。虽然统县政区与辖县的行政隶属关系明确,但现今存在的市县同城而治现象与少数民族自治州城市的管理模式,使一些市县的空间隶属关系不甚明晰,这很大程度上源于中国历史上长期存在的附郭县制度。中国传统的行政区划体系中,统县政区与辖县的空间隶属关系一直比较模糊,二者主要依靠附郭县建立起长效的空间联系。清末以后,附郭县被大量裁撤,随着城市型政区和市辖区兴起,传统的由附郭县管理城市的“城乡合治”模式走向“城乡分治”。20世纪,统县政区与辖县的空间隶属关系逐渐完成了历史演替,走向界线化、明确化的方向。新时期的行政区划改革,尤其是市县空间隶属关系的优化,应充分考量中国发展实际,重视中国政区发展的历史积淀过程。  相似文献   
19.
榆林地区景观变化探测模型   总被引:3,自引:1,他引:2  
Landscape is a dynamic phenomenon that almost continuously changes. The overall change of a landscape is the result of complex and interacting natural and spontaneous processes and planned actions by man. However, numerous activities by a large number of individuals are not concerted and contribute to the autonomous evolution of the landscape in a similar way as natural processes do. There is a well-established need to detect land use and ecological change so that appropriate policies for the ;egional sustainable development can be developed. Landscape change detection is considered to be effectively repeated surveillance and needs especially strict protocols to identify landscape change. This paper developed a series of technical frameworks on landscape detection based on Landsat Thematic Mapper (TM) Data. Through human-machine interactive interpretation, the interpretation precision was 92.00% in 1986 and 89.73% in 2000. Based on the interpretation results of TM images and taking Yulin prefecture as a case study area, the area of main landscape types was summarized respectively in 1986 and 2000. The landscape pattern changes in Yulin could be divided into ten types.  相似文献   
20.
1990-2008年中国区域经济格局时空演变   总被引:9,自引:0,他引:9  
王洋  修春亮 《地理科学进展》2011,30(8):1037-1046
对中国区域经济格局的研究较多,但以小尺度单元、时间连续、同时关注经济水平和经济增速的研究较少。本文以地级行政单位为研究单元,运用基尼系数、泰尔指数、沃尔夫森指数、集中指数、空间自相关方法和比重法分析了1990年以来中国经济总体空间差异与极化程度、经济水平和增速的全局空间自相关和"热点区"、各地经济地位的变化,并总结了主要驱动因素和演变模式。研究表明:①全国总体空间差异与极化在波动中明显增大,2003年以后继续增大。②沿海主要城市群、省会城市、特殊资源城市是"经济热点",与其他地区之间的差距逐步增大。③经济水平和经济增长的空间集聚特征明显,与全国总体经济增速具有耦合关系。④经济区位、区域政策、特殊自然资源、发展基础是中国区域经济格局形成与演变的主要驱动因素。  相似文献   
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