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51.
An industry accepted standard does not currently exist for determination of compression limits in a subsea cable. This has resulted in most manufacturers specifying that subsea cables are not permitted to be axially loaded in compression.Additionally industry guidance does not exist regarding the consequences of inducing compression forces within subsea cables and the resulting effect on cable integrity. Industry recommended practice and guidance also does not have any information regarding experimental test arrangements to determine allowable compression levels within a subsea cable. This lack of modelling/testing guidance along with manufacturer recommendations of zero compressive loads within subsea cables results in overly conservative and restrictive design parameters for subsea cable installation and use.Due to the complex interaction within a subsea cable structure, such as contact interaction and friction between cable strands, theoretical modelling has been unable to provide reliable stress predictions and therefore an experimental testing regime is required if compression limits within the cable are to be appropriately determined. This paper describes combined axial and bending test arrangements that can be used as a guideline for determination of allowable compression limits for subsea cables. 相似文献
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Aleksandar Milosavljević Dejan Rančić Aleksandar Dimitrijević Bratislav Predić Vladan Mihajlović 《International journal of geographical information science》2016,30(10):2089-2107
This paper discusses the integration of three-dimensional (3D) geographic information systems (GIS) and video surveillance systems using augmented reality (AR) techniques. The motivation for this integration is to overcome problems faced by conventional video surveillance systems. Explicit information concerning which camera currently monitors what area in such systems is missing; therefore, insight into the situation depends heavily on the operator’s training and experience. To ensure the complete coordination and monitoring of a situation in a system with multiple cameras, it is necessary to introduce a single reference system. GIS arises as a natural solution because it not only provides a solid ground truth but also provides semantic information that can be highly important in certain video surveillance applications. To integrate information into a GIS application, that information must be georeferenced. Based on our previous research regarding the addition of georeferencing information to surveillance video, this paper introduces models that can be applied to help integrate video and GIS. With an analogy to Milgram’s continuum between the real world and virtual reality, and analogous to the augmented reality and augmented virtuality in Milgram’s continuum, two models of integration are defined here: GIS-augmented video and video-augmented GIS. Then, we define the architecture of GIS-based video surveillance based on these proposed integration models, and finally, a prototype is implemented. The implemented prototype serves as a basis for analysing possible applications of real-world systems based on the integration of GIS and video. 相似文献
54.
Sébastien Darchen 《Urban geography》2016,37(2):202-222
In this paper, I question whether agglomerations of video game companies in Australia function as clusters (spatially bound) or rather as communities (not spatially bound). The two case studies included in the analysis are the main agglomerations of video companies in Australia—Brisbane and Melbourne. The data have been collected through 21 semi-structured interviews performed between 2012 and 2014. The main findings are as follows: (1) the primary reason that video game companies come together is to share tacit knowledge and skilled labour; (2) these agglomerations do not have the attributes of “creative clusters”; and (3) new technologies enable experienced game developers to operate at the geographic periphery of the main agglomeration of developers. Therefore, to paint a more accurate picture of why some video game companies are successful—beyond simply positive externalities associated with co-localization—I propose the term “networked communities.” This recognizes that social networks at varying scales (local, national, international) are being developed by video game firms in order to thrive and reach a global audience. 相似文献
55.
图像目标形状匹配与视频过滤技术研究 总被引:1,自引:0,他引:1
吴四九 《成都信息工程学院学报》2002,17(2):97-100
通过研究图像目标形状特征的提取、匹配,运用随机过程,投影理论,提出用于识别目标形状统计特性的波动度特征,建立目标形状匹配函数,给出实际图像目标的匹配实现算法,实际系统测试表明该算法能准确、快速完成实际图像目标形状的匹配、过滤,为图像跟踪、识别及视频过滤等应用领域提供了新的可借鉴方法。 相似文献
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本文着重指出了在今后处理大面积CCD图象数据过程中,所将面临的数据存贮困难问题.本文提出了一种有效的不丢失天文信息的压缩CCD图象数据的方法,对银纬b=-60°的一个天区的试验表明,压缩后的图象数据仅为原图象数据的1/30左右,并且可以十分方便地进行图象再现及再处理。在压缩数据过程中,我们在剑桥APM底片扫描机参数化施密特照相底片的基础上,重新安排了CCD图象上天体的对应参数,并视天体的大小及形状,有效地提取保存了天体周围矩阵信息. 相似文献
58.
This paper presents an examination of the timescale of phase transition behaviour of a series of salts known to cause damage
to wall paintings and other cultural property. The rate of deliquescence and crystallisation of single salts (nitromagnesite
and halite) under different RH regimes, and the extent to which this was affected when mixed with other salts (niter, nitratite
and gypsum), was investigated. The study was conducted using simple conventional techniques (mass measurements over time)
and also using an innovative new method: timelapse video imaging with online data annotation. The results demonstrate the
synergy gained from combining video imaging with environmental data in reference to time in the study of salt phase changes:
where it revealed new information concerning the kinetics of deliquescence and crystallisation. The implications of these
results for the implementation of environmental control measures within historic buildings are discussed.
相似文献
Alison SawdyEmail: |
59.
提出以C Builder 6.0为开发平台,以其所提供的TJPEGImage为核心,实现真彩色图像的压缩,为工程实际的应用提供了一种非常实用的压缩手段。该方法减少了大量程序代码的编写工作。实验表明,当综合压缩比设为65时,压缩图像与原图像相比并无明显变化,由此可见,压缩效果令人满意。 相似文献
60.
面向多种网络带宽环境的远程教学视频传输技术研究 总被引:1,自引:0,他引:1
龚自康 《武汉大学学报(信息科学版)》2006,31(4):368-371
面向网络教育教学视频传输的需求,对视频传输所涉及的视频编码、网络带宽自适应等一些关键技术进行了研究。 相似文献