共查询到20条相似文献，搜索用时 171 毫秒
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续春荣 《地壳构造与地壳应力》2005,(4):41-44
目前全球因特网所采用的协议族是TCMP协议族。IP是TCP／IP协议族中网络层的协议，是TCP／IP协议族的核心协议。目前IP协议的版本号是4（简称为IPv4），发展至今已经使用了30多年。 相似文献
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第二层通道协议（L2TP）是通过对PPP协议封装以适用于多种媒介的一个协议。它也描述了如何用UDP包对PPP协议进行封装。L2TP的最基本的两个应用是：①建立VPN连接；②实现拨号设备和拨号终端。L2TP协议由两个部分组成：L2TP访问集中器（LAC）和L2TP网络服务器（LNS）。LAC是物理上终结一个调用的设备，LNS是处理和认证PPP流的设备。作者在本文中描述了如何在WIN9X下实现L2TP协议。 相似文献
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介绍了在WinSock中注册传输协议及协议的分层和WinSock的开放系统结构及如何在应用程序中同时使用多个传输协议。同时介绍了面向连接和无连接协议两种套接种字在程序中的典型调用过程。 相似文献
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IPv6是下一代网络的关键技术，IETF从1994年开始着手研究开发下一代的IP协议即IPv6，1995年IPv6核心协议草案形成，1998年IPv6核心协议相对成熟。 相似文献
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基于TCP／IP协议的地震资料网络并行处理研究 总被引：4，自引：1，他引：3
使用ＴＣＰ／ＩＰ协议将某些地震数据处理软件设计成网络并行处理程序,可极大地提高计算效率,文章详细叙述了实现该方法的一种技术路线,对网络并行程序设计和网络并行处理中会遇到的一些问题进行了讨论,并提出了解决方案,实际运算结果证实该技术路线和解决方案是切实可行的。 相似文献
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阐述了在pSOS多任务实时操作系统内核上如何实现TCP／IP功能模拟，按照TCP／IP协议的层次结构，采用标准C语言以多进程方式对TCP／IP协议分层实现。IP是TCP／IP协议软件设计的中心环节。队列和缓冲区的管理以及进程间通信是提高协议软件效率的关键。 相似文献
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宽带接入用户认证技术分析与比较 总被引：2，自引：0，他引：2
给出了一个宽带接入用户认证系统的基本模型，并基于此模型对目前被广泛应用的PPPoE、WEB、DHCP等用户认证技术进行了分析与比较。最后，简单介绍了用户认证技术的新成员-802．1x(Port Based Network Access Control Protoco1)协议。 相似文献
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Emily Keeble David I. Whiteside Michael J. Benton 《Proceedings of the Geologists' Association. Geologists' Association》2018,129(2):99-119
Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco. 相似文献
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Gilles Serge Odin 《Comptes Rendus Geoscience》2002,334(6):409-414
Lithostratigraphy, physicochemical stratigraphy, biostratigraphy, and geochronology of the 77–70 Ma old series bracketing the Campanian–Maastrichtian boundary have been investigated by 70 experts. For the first time, direct relationships between macro- and microfossils have been established, as well as direct and indirect relationships between chemo-physical and biostratigraphical tools. A combination of criteria for selecting the boundary level, duration estimates, uncertainties on durations and on the location of biohorizons have been considered; new chronostratigraphic units are proposed. The geological site at Tercis is accepted by the Commission on Stratigraphy as the international reference for the stratigraphy of the studied interval. To cite this article: G.S. Odin, C. R. Geoscience 334 (2002) 409–414. 相似文献
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The effect of water on accessory phase solubility in subaluminous and peralkaline granitic melts 总被引：4，自引：0，他引：4
The solubilities of columbite, tantalite, wolframite, rutile, zircon and hafnon were determined as a function of the water contents in peralkaline and subaluminous granite melts. All experiments were conducted at 1035 °C and 2 kbar and the water contents of the melts ranged from nominally dry to approximately 6 wt.% H2O. Accessory phase solubilities are not affected by the water content of the peralkaline melt. By contrast, solubilities are affected by the water content of the subaluminous melt, where the solubilities of all the accessory phases examined increase with the water content of the melt, up to 2 wt.% H2O. At higher water contents, solubilities are nearly constant. It can be concluded that water is not an important control of accessory phase solubility, although the water content will affect diffusivities of components in the melt, thus whether or not accessory phases will be present as restite material. The solubility behaviour in the subaluminous and peralkaline melts supports previous spectroscopic studies, which have observed differences in the coordination of high field strength elements in dry vs. wet subaluminous granitic glasses, but not for peralkaline granitic glasses. Lastly, the fact that wolframite solubility increases with increasing water content in the subaluminous melt suggests that tungsten dissolved as a hexavalent species. 相似文献
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Muriel Rocher Stéphane Baize Stéphane Jaillet Edward Marc Cushing Yannick Lozac&#x;h Francis Lemeille 《Comptes Rendus Geoscience》2003,335(8):701-708
Calcite samples were extracted both from the rock matrix and the superficial coating of a karstified fault plane of an underground quarry, located in the eastern border of the Paris basin. The karstification is dated as Quaternary. Analysis of mechanical calcite twinning reveals that only the calcite matrix has also undergone a compression trending WNW that can be attributed to the Mio-Pliocene alpine collision. Both coating and matrix have undergone a strike-slip regime with σ1 roughly trending north–south, that could correspond to the regional present-day state of stress, a strike-slip compression rather trending NNW, modified by local phenomena. To cite this article: M. Rocher et al., C. R. Geoscience 335 (2003). 相似文献
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正20141520 Bo Ying(Key Laboratory of Metallogeny and Mineral Assessment,MLR,Beijing 100037,China);Liu Chenglin Saline Spring Hydrochemical Characteristics and Indicators for Potassium Exploration in Southwestern and Northern Tarim Basin,Xinjiang(Acta Geoscientica Sinica,ISSN1006-3021,CN11-3474/P,34(5),2013,p.594-602,5 illus.,3 tables,28 refs.) 相似文献
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正20141243Chen Ge(Hangzhou Research Institute of Petroleum Geology,PetroChina,Hangzhou 310023,China);Si Chunsong Study on Sedimentary Numerical Simulation Method of Fan Delta Sand Body(Journal of Geology, 相似文献
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正20142599Chen Sanming(Guangxi Key Laboratory of Concealed Deposits Exploration,Guilin University of Technology,Guilin541004,China);He Yuzhou Block Model and Reserves Estimation of Panzhihua Iron Deposit Based on 3D Geological Modeling(Journal of Guilin University of Technology,ISSN1674-9057,CN45-1375/N,33(4),2013,p.610-615,9illus.,1table,15refs.) 相似文献
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正20140594 Bai Daoyuan(Hunan Institute of Geology Survey,Changsha 410016,China);Zhong Xiang Faults in the Jingzhou Basin and Their Tectonic Settings(Geotectonica et Metallogenia,ISSN1001-1552,CN44-1595/P,37(2),2013,p.173-183,6illus.,59refs.)Key words:basin evolution,tectonic setting,South China In the Upper Paleozoic and Jurassic se- 相似文献
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正20141912Cao Hui(State Key Laboratory for Continental Tectonics and Dynamics,Institute of Geology,Chinese Academy of Geological Sciences,Beijing 100037,China)Gravitational Collapse and Folding during Orogenesis:A Comparative Study of FIA Trends and Fold Axial Plane Traces(Geology in China,ISSN1000-3657,CN11-1167/P,40(6),2013,p.1818-1828,9illus.,35refs.,with 相似文献