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51.
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北京城市快速发展时期双井老工业区转型研究 总被引:1,自引:1,他引:0
20世纪90年代以来,北京的城市发展和产业结构调整进入到了新的快速发展时期,受其影响,城区内原有的老工业区也加快了转型调整的步伐.双井老工业区的转型正是在这个特殊时期进行的,通过描述双井老工业区的发展历程和转型后的现状,深入探讨了老工业区转型的动力机制以及转型过程中暴露出的诸多矛盾,最后,从社会主义市场经济角度和城市建设角度提出发展建议. 相似文献
53.
The ‘fit-for-purpose’ (FFP) approach was developed to respond to the challenges that the creation of a sustainable land administration system (LAS) faces. FFP has proved its value in integrating technological innovations such as unmanned aerial vehicles (UAVs) in LAS. Technological innovations need to consider the governance context when being implemented. Understanding the relevance of the FFP approach and acknowledging the importance of the governance context, this research applies the ‘Fit-for-purpose governance assessment framework’ (FGAF). FGAF helps to understand the challenges that the implementation of UAVs can face in the LAS in Kenya. This governance assessment is based on 16 semi-structured in-depth interviews, three one-day workshops with local stakeholders and UAVs pilot studies to test the technology. The findings suggest that there are major and minor challenges concerning different attributes of FFP qualities. The governance context across counties is fragmented with a high degree of uncertainty and uneven capacity conditions. There are overlapping responsibilities and trust issues among the different actors. Participation of private and non-governmental actors is limited. Yet, steps have been taken toward the adoption of innovative approaches. Although financial resources are limited, the diversity of local and international stakeholders can work as a leverage point to support the implementation of UAVs in the mid and long-term. 相似文献
54.
Based on DEM of Qinling Mountains, used the model of the center cell and the adjacent eight cells, we calculated the surface area of Shaanxi section Qinling Mountains. The results shows that: (1) The surface area of Shaanxi section Qinling Mountains is 75 224.67 km2, which is an increase of 22.04% from the vertical projection area;(2)The relation between the difference of surface area and vertical projection area and elevation is parabolic. The altitude of 2 000 meters is the area with the largest difference between the surface area and the vertical projection area in Shaanxi section Qinling mountains;(3)Compared with the vertical projection area, the area of low mountains, medium mountains and submountains in Shaanxi section of the Qinling mountains increased by 2 301.54 km2, 6 181.67 km2 and 691.60 km2 respectively, with the growth rate of 10.68%, 18.37% and 18.25% respectively.(4)The difference between the surface area and the vertical projection area is various in different land use types. Not using land is the largest, the difference is 34%. The second is forest land which the difference is 28%, and the lawn is approximately 20%. Difference is small in farmland, other forest land, water and residents and industrial land, which is 12%, 8%, 5% and 8% in turn. 相似文献
55.
MODIS数据陆面温度反演研究 总被引:17,自引:1,他引:17
陆面温度(LST,landsurfacetemperature)是研究地表和大气之间物质交换和能量交换的重要参数。基于推广的分裂窗算法,运用MODIS数据,在青海湖地区(200km*200km)进行了陆面温度反演研究。在实验区,推广的分裂窗算法传感器高度角大于40°,将原分裂窗的区间进行了细化,与分裂窗方法相比,传感器高度角在40°~50°,大气柱水汽含量小于1.5cm时,反演精度较高,小于1K;与分裂窗方法类似,该方法对比辐射率和传感器仪器质量的误差不甚敏感。 相似文献
56.
57.
若尔盖县是世界著名若尔盖湿地的主要组成部分, 是青藏高原高寒生态系统的典型代表。基于1989 年、1997 年和2004 年3 期Landsat TM 影像的土地利用ö土地覆被分类结果, 运用地理信息系统空间分析方法和数理统计学方法, 深入分析了四川省若尔盖县近15 年来各土地利用/覆被类型尤其是草地和沼泽的数量和空间变化特征。结果表明: ①研究区主要土地利用与土地覆被类型为草地、沼泽、林地和裸地, 其中草地与沼泽面积逐步减少, 而裸地面积成倍增长。②通过建立研究区LU CC 幅度、LU CC 数量和空间变化模型以及趋势与状态指数模型, 很好的表现了研究区LU CC 的时空特征。从整个区域来看, 前期综合LU CC 趋势和状态指数为0. 37, 处于准平衡状态;后期小于前期, 为0. 23, 处于平衡状态, 整个时段其指数为0. 35, 为准平衡状态, 呈现双向转换态势。③定位分析了研究区LU CC 情况, 发现区域草地和沼泽退化相当严重, 而且前后两期退化区在空间上有所转移。 相似文献
58.
Regional evaporation estimates from flux tower and MODIS satellite data 总被引:10,自引:0,他引:10
Two models were evaluated for their ability to estimate land surface evaporation at 16-day intervals using MODIS remote sensing data and surface meteorology as inputs. The first was the aerodynamic resistance-surface energy balance model, and the second was the Penman-Monteith (P-M) equation, where the required surface conductance is estimated from remotely-sensed leaf area index. The models were tested using 3 years of evaporation and meteorological measurements from two contrasting Australian ecosystems, a cool temperate, evergreen Eucalyptus forest and a wet/dry, tropical savanna. The aerodynamic resistance-surface energy balance approach failed because small errors in the radiative surface temperature translate into large errors in sensible heat, and hence into estimates of evaporation. The P-M model adequately estimated the magnitude and seasonal variation in evaporation in both ecosystems (RMSE = 27 W m− 2, R2 = 0.74), demonstrating the validity of the proposed surface conductance algorithm. This, and the ability to constrain evaporation estimates via the energy balance, demonstrates the superiority of the P-M equation over the surface temperature-based model. There was no degradation in the performance of the P-M model when gridded meteorological data at coarser spatial (0.05°) and temporal (daily) resolution were substituted for locally-measured inputs.The P-M approach was used to generate a monthly evaporation climatology for Australia from 2001 to 2004 to demonstrate the potential of this approach for monitoring land surface evaporation and constructing monthly water budgets from 1-km to continental spatial scales. 相似文献
59.
Atmospheric correction of optical imagery from MODIS and Reanalysis atmospheric products 总被引:2,自引:0,他引:2
Juan C. Jiménez-Muñoz Cristian Mattar Belen Franch 《Remote sensing of environment》2010,114(10):2195-2210
In this paper we analyze the differences obtained in the atmospheric correction of optical imagery covering bands located in the Visible and Near Infra-Red (VNIR), Short-Wave Infra-Red (SWIR) and Themal-Infrared (TIR) spectral regions when atmospheric profiles extracted from different sources are used. In particular, three sensors were used, Compact High Resolution Imaging Spectrometer (CHRIS), Advanced Spaceborne Thermal Emission and Reflection radiometer (ASTER) and Landsat5 Thematic Mapper (TM), whereas four atmospheric profiles sources were considered: i) local soundings launched near the sensor overpass time, ii) Moderate Resolution Radiometer (MODIS) atmospheric profiles product (MOD07), iii) Atmospheric Correction Parameter Calculator (ACPC) generated by the National Center for Environmental Prediction (NCEP) and iv) Modified Atmospheric Profiles from Reanalysis Information (MAPRI), which includes data from NCEP and National Center of Atmospheric Research (NCAR) Reanalysis project but interpolated to 34 atmospheric levels and resampled to 0.5° × 0.5°. MODIS aerosol product (MOD04) was also used to extract Aerosol Optical Thickness (AOT) values at 550 nm. Analysis was performed for three test dates (12th July 2003, 18th July 2004 and 13th July 2005) over an agricultural area in Spain. Results showed that air temperature vertical profiles were similar for the four sources, whereas dew point temperature profiles showed significant differences at some particular levels. Atmospheric profiles were used as input to MODTRAN4 radiative transfer code in order to compute atmospheric parameters involved in atmospheric correction, with the aim of retrieving surface reflectances in the case of VNIR and SWIR regions, and Land Surface Temperature (LST) in the case of the TIR region. For the VNIR and SWIR region, significant differences depending on the atmospheric profile used were not found, particularly in the Visible region in which the AOT content is the main parameter involved in the atmospheric correction. In the case of TIR, differences depending on the atmospheric profile used were appreciable, since in this case the main parameter involved in the atmospheric correction is the water vapor content, which depends on the vertical profile. In terms of LST retrieval from ASTER data (2004 test case), all profiles provided satisfactory results compared to the ones obtained when using a local sounding, with errors of 0.3 K for ACPC and MAPRI cases and 0.7 K for MOD07. When retrieving LST from TM data (2005 test case), errors for MOD07 and MAPRI were 0.6 and 0.9 K respectively, whereas ACPC provided an error of 2 K. The results presented in this paper show that the different atmospheric profile sources are useful for accurate atmospheric correction when local soundings are not available. In particular, MOD07 product provides atmospheric information at the highest spatial resolution, 5 km, although its use is limited from 2000 to present, whereas MAPRI provides historical information from 1970 to present, but at lower spatial resolution. 相似文献
60.
现阶段地价动态监测工作基本依赖手工进行,仅仅停留在对监测数据的计算上,没有考虑利用GIS技术,工作周期长,严重影响着地价监测工作的科学性和高效率.本文设计开发一个基于GIS的城市地价动态监测信息系统,旨在实现对地价数据的有效管理和充分利用,提高地价监测和更新工作准确性、科学性和实时性,还分析了各个功能的设计与实现,例如工程管理功能、地价监测功能、地价分析与预警功能等. 相似文献