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991.
Soon-Sup Lee Jong-Kap Lee Beom-Jin Park Dong-Kon Lee Soo-Young Kim Kyung-Ho Lee 《Ocean Engineering》2006,33(13):1814-1828
In this paper, internet-based ship technical information management system has been developed as a means to accumulate, manage, share and utilize various distributed applications and information used for ship design and building. The information managed in the system is documents from the whole life cycle including concept design, basic design, detailed design, construction, operation and maintenance. In addition, using the developed system, integrated system framework is also proposed to integrate applications and database in concurrent engineering environment. 相似文献
992.
Seungshic Yum Seonock Woo Man Chang Taek-Kyun Lee Jun-Im Song 《Ocean Science Journal》2005,40(1):55-59
We cloned the complete cDNA of the β-tubulin from the soft coral,Scleronephthya gracillimum (Kükenthal) (Alcyonacea, Octocorallia, Anthozoa, Cnidaria), via the random sequencing of a cDNA library and the 5′-rapid
amplification of cDNA end (RACE) technique. The full-length cDNA of theS. gracillimum β-tubulin comprised 1541 bp, not including the poly (A)+ stretch, also contained a complete open reading frame, which codes for a total of 445 amino acids. The amino acid residues
16-402 appeared to be in a state of conservation in a variety of animals. Northern blot analysis clearly demonstrated that
the sequence we have obtained is, indeed, the full-length cDNA of the β-tubulin gene inS. gracillimum. 相似文献
993.
Recovery of surface-wave time series from pressure gage data is a time-consuming process and is not customarily carried out. Such information is, however, useful particularly in real-time for warning of freak waves or waves of unusual characteristics. Two simple numerical filters are developed here to serve such purpose. The first method is a linear filter with a built-in window to suppress high-frequency noise. The second method recovers the surface wave by computing the local surface curvature. These filters are very simple and can be programmed into a microprocessor to be integrated into field instrument packages.Both filters have been tested satisfactorily against conventional linear filters using simulated wave data and wave data collected in intermediate water depth. Neither filter requires pre-filtering of noise from raw data, which is commonly required to recover surface-wave information from sub-surface pressure data. 相似文献
994.
An accurate particle tracking method for a finite difference method model is developed using a constant acceleration method.
Being assumed constant temporal and spatial gradients, the new method permits temporal-spatial variability of particle velocity.
Test results in a solid rotating flow show that the new method has second-order accuracy. The performance of the new method
is compared with that of other methods; the first-order Euler forward method, and the second-order Euler predictorcorrector
method. The new method is the most efficient method among the three. It is more accurate and efficient than the other two. 相似文献
995.
The spatial variability of Holocene (past 10,000 years) sediment accumulation in Santa Monica Bay (California) was examined to identify controls sediment trapping in a bathymetrically complex coastal embayment and to provide geologic context for the post-industrial sedimentary record and associated pollution gradients. Sediment chronologies based on downcore AMS 14C dates were used to quantify long-term (millennia) accumulation rates in an effort to elucidate particle-transport pathways and sinks. Sediment accumulation rates for the full range of bayfloor environments (50-630 m water depths) range from 22 to 102 mg/cm(2)/year (15-88 mm/100 year), have an overall mean of 51+/-21 mg/cm(2)/year (1 sigma, n=11), and are comparable to rates reported for adjacent borderland basins. Maximal accumulation rates on the Malibu shelf and within a reentrant to Redondo canyon are interpreted to reflect (1) proximity to sediment sources and (2) localized oceanographic and topographic conditions conducive to sediment trapping and deposition. The 14C-derived accumulation rates are 2-10 times lower than rates determined through (210)Pb geochronology for the same sites in a related study, revealing that Holocene sediment accumulation has been non-steady-state. Santa Monica Bay is an important sink for suspended matter; averaged over the past several millennia a mass of sediment equivalent to 10-80% of the modern annual river supply is sequestered yearly. Net influx of suspended matter derived from the adjacent Palos Verdes shelf is evinced by a concentration gradient of p,p'-DDE in bayfloor sediments, whereas the distribution of anthropogenic silver suggests transport from Santa Monica shelf to the southeastern boundary of the bay. The results of this study provide new insight to the long-term fates of particulate matter in Los Angeles coastal waters. 相似文献
996.
The resonance period of the L-shaped channel in the caisson is predicted analytically for the seawater exchange breakwater of “Applicability Study of the Seawater Exchange Breakwater (1). Korea Ministry of Maritime Affairs and Fisheries (in Korean) (1999a)”. Hydraulic experiments are conducted for a composite breakwater with a rear reservoir that is one of the seawater exchange breakwaters developed by them. For regular waves, the water surface elevation in the channel and the flow rate through the breakwater are measured. For irregular waves, the flow rate through the breakwater and the reflection coefficient on the breakwater are measured. The resonant maximum values in both the surface elevation and the flow rate, and the resonant minimum values in the reflection coefficient are all at wave periods slightly longer than analytically predicted ones. The measured resonance period for irregular waves is closer to the predicted one than for regular waves. If the resonance period of the L-shaped channel is fitted to the dominant period of incident waves, there would be high efficiency of seawater exchange between inside and outside the harbor. 相似文献
997.
998.
999.
Jeffrey?W.?BookEmail author Pavel?Pistek Henry?Perkins Keith?R.?Thompson William?J.?Teague Gregg?A.?Jacobs Moon-Sik?Suk Kyung-Il?Chang Jae-Chul?Lee Byung?Ho?Choi 《Journal of Oceanography》2004,60(6):977-993
During 1999–2000, 13 bottom mounted acoustic Doppler current profilers (ADCPs) and 12 wave/tide gauges were deployed along two lines across the Korea/Tsushima Strait, providing long-term measurements of currents and bottom pressure. Tidally analyzed velocity and pressure data from the moorings are used in conjunction with other moored ADCPs, coastal tide gauge measurements, and altimeter measurements in a linear barotropic data assimilation model. The model fits the vertically averaged data to the linear shallow water equations in a least-squares sense by only adjusting the incoming gravity waves along the boundaries. Model predictions are made for the O1, P1, K1, μ2, N2, M2, S2, and K2 tides. An extensive analysis of the accuracy of the M2 surface-height predictions suggests that for broad regions near the mooring lines and in the Jeju Strait the amplitude prediction errors are less than 0.5 cm. Elsewhere, the analysis suggests that errors range from 1 to 4 cm with the exception of small regions where the tides are not well determined by the dataset. The errors in the model predictions are primarily caused by bias error in the model’s physics, numerics, and/or parameterization as opposed to random errors in the observational data. In the model predictions, the highest ranges in sea level height occur for tidal constituents M2, S2, K1, O1, and N2, with the highest magnitudes of tidal velocities occurring for M2, K1, S2, and O1. The tides exhibit a complex structure in which diurnal constituents have higher currents relative to their sea level height ranges than semi-diurnal constituents. 相似文献
1000.
Louis C. St. Laurent Jonathan D. Nash 《Deep Sea Research Part II: Topical Studies in Oceanography》2004,51(25-26):3029
In this study, the energy flux and energy dissipation of deep ocean internal tides are examined. Properties of the internal tide from two distinct generation regions are contrasted: the Mid-Atlantic Ridge (MAR) and the Hawaiian Ridge. Considerable differences are noted for the baroclinic energy flux, u′p′, radiated from each site. Radiation from the MAR is relatively rich in high modes, with an energy flux spectral peak at mode 5 and modes 10 and greater accounting for 40% of the total flux. In contrast, Hawaiian Ridge radiation is dominantly composed of modes 1 and 2, with modes 10 and greater accounting for less than 5% of the total flux. Depth integrated energy flux levels are at the MAR site, and at the Hawaiian Ridge. Despite these differences, observed turbulent dissipation rates at these sites are similar in magnitude and depth dependence. Decay scales, estimated as , range from O(100)km to . The mean decay scale based on the MAR data is 230 km, a factor of 3 smaller than at the Hawaiian Ridge site. We demonstrate that the dissipation level scales with the energy flux available in the high modes, which is comparable at both sites, rather than the total energy flux. 相似文献