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961.
Brantson Eric Thompson Ju Binshan Ziggah Yao Yevenyo Akwensi Perpetual Hope Sun Yan Wu Dan Addo Bright Junior 《Natural Resources Research》2019,28(3):717-756
Natural Resources Research - The most widely used production decline forecasting tools are numerical reservoir simulation, material balance estimates and advanced methods of production decline... 相似文献
962.
科学评估土地利用总体规划管控建设用地扩张的成效对于规划编制方法和规划管理措施的改进意义重大。本文基于土地利用总体规划的相关指标,从时间、空间、数量和质量等视角构建城镇扩张评估指标体系,选择快速城市化地区南京市为例进行研究。主要结论为:① 南京市土地利用总体规划对建设用地扩张强度的管控有一定成效但仍需加强。规划期除2013年以外,其余年份新增城镇工矿用地规模均高于规划年均控制规模,至2015年指标使用进度高达78.83%,规划剩余年限用地需求难以满足;② 南京城市空间扩张态势与规划城镇用地空间扩张格局基本吻合。不同方向指标使用进度存在较大的差异性,呈东北和西北部快、南部慢的格局;集中度和合规度指标较好;③ 评估期内规模控制指数为-0.97,空间溢出指数为0.34,规划对新增城镇工矿用地管控力度偏弱,规划的累积执行效果呈逐年变差的趋势。④ 本文构建的指标体系可全方位、多角度评估城镇扩张的规划管控成效,对其他地区的规划实施评估有一定的借鉴意义。 相似文献
963.
964.
台风Bogus资料的四维变分同化试验 总被引:1,自引:0,他引:1
给出人造台风(即Bogus)资料同化方案,并用于生成台风的初始结构,同时用9608号台风进行了测试,资料同化和预报均采用第5代中尺度模式系统(The Fifth-Generation NCAR/Penn State Mesoscale Model,简称MM5),结果发现该方案能产生成熟台风的许多结构特征,对9608号台风的预报也有明显改进.模式的初始场更适合于预报模式,能有效抑制积分初期的旋转加强(即Spinup)现象;强度预报和路径预报都得到改善,Bogus资料同化方案的各时次路径预报误差均比Bogus资料直接嵌入方案的误差要小. 相似文献
965.
This study investigates a construction-induced sea level rise and tide characteristics change, using a regression analysis to separate the local construction effect such as sea-dike/seawalls and global warming from total sea level change. The study also makes it clear why and how the extreme high water level has risen just after constructions at Mokpo harbor in Korea. As a result of the regression analysis, it is found that the high water level rise for the period of 1960–2006 is ~60 cm, which is summation of four components: ~23 cm for Youngsan River sea-dike (1981), ~15 cm for Youngam seawall (1991), ~8 cm for Geumho seawall (1994), and ~14 cm for gradual rise (due mainly to global warming). Then, a numerical simulation at Mokpo coastal zone is performed to identify each component, and the results support the premise that the tidal amplification caused by constructions is due mainly to the extinguishment of the tidal choking effect at outer Mokpogu. The tidal flat effect makes the amplification greater at spring tide or extraordinary high tide, which would result in the increase of inundation risk at the Mokpo coastal zone. Frequency distribution of observed high water level data shows increasing trend for both maximum value of astronomical tide component (simulated high water level) and meteorological tide component (surge height) after the coastal constructions. A frequency analysis presents that the high water level for 50 year return period, which is often used for design in practice, is 474 cm before the construction, and while that is 553 cm after the construction. Furthermore, design height might steadily be elevated considering future global sea level rise. 相似文献
966.
Totally 2472 grains of Radiolaria belonging to 36 Genera and 45 species are distinguished from 12 surface sediments in the Bering Sea. The distribution characteristics of Radiolaria fossils in the surface sediments are as follows: (1) From the shelf of shallow water to the upper of continental slope, there are a few Radiolaria fossils and monotonous genus and species; (2) In the lower of continental slope, Radiolaria fossils are poor in the volcanic cinders and turbidite; (3) The abundance and diversity of Radiolaria fossils are high in clay of the basin. The dominant species of Radiolaria is Spongotrochus glacialis on the continental shelf. Current, topography, water depth, and temperature etc. are key factors influencing Radiolaria distribution. The sources of sediments mainly are terrigenous, biogenic and volcanic sediments in the survey area and they are mostly from the Kamchatka peninsula in the east of Russia and the Aleutian Islands. 相似文献
967.
Although Morison equation is often applied for simulating hydrodynamic force of marine structure, it may give poor results when non-linear behavior is severe or random wave is encountered. This leads to some modifications of Morison equation or other methods for predicting hydrodynamic force. One of them is the system identification technique. In this paper, NARMAX model theory is firstly used to identify the hydrodynamic system of heave damping plates, which are commonly installed on spar platform. Both linear and non-linear models are obtained. The comparisons between the predieted results and measured data indicate that NARMAX model can predict hydrodynamic force of a heave damping plate very well. The measured data for identification originate from forced oscillation tests, which are random records with given spectrum. The forced oscillation forms in experiment also contain simple harmonic, multi-frequency ones. 相似文献
968.
本文提出了一种新型的多波长全光再生方案,利用相位时钟光纤光参量放大,并采用相邻信道偏振正交的方法,实现对由异步信源产生的双波长信号全光再生.理论分析了参量放大中的增益饱和现象用于幅度噪声抑制,以及利用相位时钟及后续色散实现对信号定时的机理.在这个基础上,对两个独立信源产生的异步双波长10 Gbit/s信号进行再生实验,实验表明该方案有效的抑制了基于多波长3R再生系统中信道间的四波混频与交叉相位调制等非线性干扰.系统在单波长和双波长情况下分别将两路信号信噪比改善了至少6.5 dB与4.5 dB.误码率测试结 相似文献
969.
970.