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201.
The impact of the risk environment and energy prices to the budget of Korean households 总被引:2,自引:2,他引:0
Hyungho Youn Byung In Lim Eui Young Lee YongRok Choi 《Stochastic Environmental Research and Risk Assessment (SERRA)》2011,25(3):323-330
Energy is closely related to environmental risk. A rising fuel price in the 1970s had hurt consumers and caused disturbance
to the natural environment. Households could not afford high imported energy prices and thus resorted to fuel wood. Land competed
for fuel wood and agricultural crops, and thus high fuel prices strained the environment with respect to the use of land.
If human health and safe housing were included in environmental risk, a high energy price would induce broader environmental
risk. Households with limited income would not be able to use expensive fossil energy to warm their houses and would depend
on only electric mats or blankets to keep warm. Such insufficient warming methods would not only threaten their health but
would also worsen the condition of their houses. The abrupt increase in energy prices in 2007 and 2008 had significantly impacted
environmental risk. It forced low income households to spend more on energy, leaving less for other expenditure segments,
but had left high income households generally intact. This contrasting effect between different income groups had increased
the sustainability of the energy risks at the high prices. This study shows how risks associated with the household economy
have increased in response to the recent dramatic increases in energy prices. We develop a method for assessing risk by using
the variance of ratios of energy expenditure to current income. We then examine how differently the economic change has increased
risk across expenditure segments. We find energy expenditure as the biggest contributor to the risk. In addition, we illustrate
how energy expenditure has changed the risk profile for each income group, with the first group (i.e., the lowest income group)
experiencing the greatest increase. This group hurts the most during days of high energy prices. 相似文献
202.
Benthic ecosystem in Gwangyang Bay, a fast developing industrial area with steel production, port container handling, petroleum and other chemical processing in South Korea was studied. The average levels of polychlorinated biphenyls (ΣPCB) in the benthic components were: seawater 2.99 ± 0.13 (ng/L); sediment 294 ± 118 (ng/g TOC); [biota=ng/g lipid] starfish 92; prawn 131 ± 2; mussels 127 ± 22; crab 182 ± 114; clam 187; polychaeta 215; sea cucumber 497 ± 90; squill 603 ± 38; fish 396 ± 159. Levels in the inner bay samples were higher than the outer bay samples suggesting land based pollution. Good correlation (r(2)=0.79; p<0.05) existed between PCB concentration and lipid content indicating partitioning processes in action. PCB signature in the abiotic and biotic components shows enrichment of lower chlorinated congeners emitted by a unique source nearby, viz. steel manufacturing plant. 相似文献
203.
Stabilization of arsenic-contaminated mine tailings using natural and calcined oyster shells 总被引:1,自引:0,他引:1
Deok Hyun Moon Kyoung-Woong Kim In-Ho Yoon Dennis G. Grubb Dae-Yewn Shin Kyung Hoon Cheong Hyung-Il Choi Yong Sik Ok Jeong-Hun Park 《Environmental Earth Sciences》2011,64(3):597-605
Natural oyster shells (NOS) and calcined oyster shells (COS) were used to immobilize arsenic (As) from contaminated mine tailings.
In addition, a blend of Portland cement (PC)/cement kiln dust (CKD) was used as a stabilizing agent. The Korean Standard Test
(KST) method (1 N HCl extraction) was used to evaluate the effectiveness of the treatment. The experimental results showed
that COS effectively immobilized As in treated mine tailings. Specifically, an As concentration less than 1 mg L−1 was obtained following COS treatment at 25 and 30 wt%. However, all the samples subjected to NOS treatments failed the Korean
warning standard of 1.2 mg L−1 after 28 days of curing. All of the COS-PC treatments were successful meeting the Korean warning standard after 7 days of
curing. However, the PC-only treatment failed to meet the Korean warning standard. Similarly, the CKD-only treatment was failed
to meet the Korean warning standard after 7 days of curing. However, the COS-CKD treatment showed that when the COS content
was greater than 20 wt%, less than 1 mg L−1 of As leachability was obtained. Scanning electron microscopy–energy dispersive X-ray spectroscopy (SEM–EDX) showed needle-like
and torpedo-like Ca–As phases in the COS-treated samples suggesting that As was strongly associated with Ca and O. X-ray absorption
near edge structure (XANES) analyses confirmed that As(V) was prevalent in the tailings and that there were no changes in
As speciation following NOS or COS treatment. 相似文献
204.
Sensitivity analysis for the GIS-based mapping of the ground subsidence hazard near abandoned underground coal mines 总被引:3,自引:3,他引:0
Ground subsidence around abandoned underground coal mines can cause much loss of life and property. We analyze factors that
can affect ground subsidence around abandoned mines in Jeongahm in Kangwon-do by sensitivity analysis in geographic information
system (GIS). Spatial data for the subsidence area, topography and geology and various ground engineering data were collected
and used to make a factor raster database for a ground subsidence hazard map. To determine the importance of extracted subsidence-related
factors, frequency ratio model and sensitivity analysis were employed. Sensitivity analysis is a method for comparing the
combined effects of all factors except one. Sensitivity analysis and its verification showed that using all factors provided
91.61% accuracy. The best accuracy was achieved by not considering the groundwater depth (92.77%) and the worst by not considering
the lineament (85.42%). The results show that the distance from the lineament and the distance from the drift highly affected
the occurrence of ground subsidence, and the groundwater depth, land use and rock mass rating had the least effects. Thus,
we determined causes of ground subsidence in the study area and this information could help in the prediction of ground subsidence
in other areas. 相似文献
205.
National-scale assessment of landslide susceptibility to rank the vulnerability to failure of rock-cut slopes along expressways in Korea 总被引:2,自引:1,他引:1
Jangwon Suh Yosoon Choi Tae-Dal Roh Hyi-Jun Lee Hyeong-Dong Park 《Environmental Earth Sciences》2011,63(3):619-632
The objective of this study is to perform a preliminary national-scale assessment of the landslide susceptibility of rock-cut slopes along expressways in Korea. A geographic information system (GIS) database was compiled based on data from topographical and geological maps, and rock-cut slope data, including the locations of past landslides. Seven factors (i.e., slope height, slope length, slope gradient, upper slope gradient, lithology, distance from nearest fault, and dip direction of slope) were extracted from the GIS database to assess the relationship between each factor and landslide events. Weight of evidence (WOE), analytic hierarchy process (AHP), and fuzzy logic methods, as well as hybrid methods, were used to establish the rating of classes for each factor, weightings for the factors, and to combine multiple factor layers into landslide-susceptibility maps. A comparison of the results obtained using several different methods, based on the area under curve technique, revealed that the WOE method showed the highest accuracy of 74%. The annual cost of traffic congestion resulting from slope failures was evaluated to identify those rock-cut slopes where detailed investigations and landslide warning systems are required. 相似文献
206.
Ships experience roll motion due to waves in a seaway. Therefore, fin stabilizers are installed to stabilize such roll motion. A fin stabilizer is effective at reducing the roll motion at moderate speeds but not at low speeds. Recently, pod propellers have been used with fin stabilizers for roll stabilization. In the paper, a MIMO (multi-input multi-output) optimal control system that has two control inputs such as fin stabilizers and pod propellers is designed. The LQR (linear quadratic regulator) control algorithm is applied to reduce the roll motion of cruise ships in regular waves. Also, the nominal plant and the frequency-weighted LQR are applied to reduce the roll motion in irregular waves. The roll motion of cruise ships is effectively reduced when the fin and pod propeller are used as the control actuators at low speeds. The optimal control gain is easily found when the frequency-weighted LQR is applied. 相似文献
207.
Northern Folgefonna (c. 23 km2), is a nearly circular maritime ice cap located on the Folgefonna Peninsula in Hardanger, western Norway. By combining the position of marginal moraines with AMS radiocarbon dated glacier‐meltwater induced sediments in proglacial lakes draining northern Folgefonna, a continuous high‐resolution record of variations in glacier size and equilibrium‐line altitudes (ELAs) during the Lateglacial and early Holocene has been obtained. After the termination of the Younger Dryas (c. 11 500 cal. yr BP), a short‐lived (100–150 years) climatically induced glacier readvance termed the ‘Jondal Event 1’ occurred within the ‘Preboreal Oscillation’ (PBO) c. 11 100 cal. yr BP. Bracketed to 10 550–10 450 cal. yr BP, a second glacier readvance is named the ‘Jondal Event 2’. A third readvance occurred about 10 000 cal. yr BP and corresponds with the ‘Erdalen Event 1’ recorded at Jostedalsbreen. An exponential relationship between mean solid winter precipitation and ablation‐season temperature at the ELA of Norwegian glaciers is used to reconstruct former variations in winter precipitation based on the corresponding ELA and an independent proxy for summer temperature. Compared to the present, the Younger Dryas was much colder and drier, the ‘Jondal Event 1’/PBO was colder and somewhat drier, and the ‘Jondal Event 2’ was much wetter. The ‘Erdalen Event 1’ started as rather dry and terminated as somewhat wetter. Variations in glacier magnitude/ELAs and corresponding palaeoclimatic reconstructions at northern Folgefonna suggest that low‐altitude cirque glaciers (lowest altitude of marginal moraines 290 m) in the area existed for the last time during the Younger Dryas. These low‐altitude cirque glaciers of suggested Younger Dryas age do not fit into the previous reconstructions of the Younger Dryas ice sheet in Hardanger. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
208.
M. Favre P. Silva H. Chuaqui E. Wyndham P. Choi 《Astrophysics and Space Science》1997,256(1-2):485-490
We present preliminary time and space resolved studies of current sheath formation in Plasma Focus discharges, using a novel array of non-invasive magnetic field probes. The experiments are performed in a Mather type plasma focus, operating at 2 kV. The discharge is formed between a hollowed anode and six symmetrically arranged cathode rods. The array of small magnetic probes is located along the cathode rods. The probes are of millimeter size. They are shielded behind the rods, as to minimize capacitive coupling to the anode electrode, and allow non-perturbing measurements to be made. A simple analytical model of current sheath evolution is used to analyze the probe signals. The experiments have been performed in pure Hydrogen and Hydrogen with Argon mixture, at pressures from below 0.2 Torr upwards. The effect of the Argon mixture on the current sheath structure is investigated with the probe array. It is found that at constant mass density operation, the increase in the percentage of Argon results in a thinner sheath, with steeper current profile. 相似文献
209.
Rock surface weathering, as reflected by rock surface hardness and roughness, was measured at six mountains along an east-west transect across southern Norway. At most sites the results show significant differences in rock surface weathering across the autochthonous blockfield boundary, suggesting that the areas above the boundary have been exposed to subaerial weathering for a considerably longer time span that the areas below. The results are interpreted as reflecting the surface profile of an asymmetric, west-centred, low-gradient ice sheet. 相似文献
210.
Spindel R.C. Jungyul Na Dahl P.H. Suntaek Oh Eggen C. Young Gyu Kim Akulichev V.A. Morgunov Y.N. 《Oceanic Engineering, IEEE Journal of》2003,28(2):297-302
A pilot experiment was conducted in the Sea of Japan (also called the East Sea) in September-October 1999, to assess the possibility of using acoustic tomographic techniques for monitoring water mass structure and dynamics. Acoustic m-sequence signals at various frequencies between 250 and 634 Hz were transmitted from bottom-mounted acoustic sources in shallow water off the coast of Vladivostok to vertical-array receiving systems deployed off the north coast of Ulleung-Do island (S. Korea), 558 km to the south. The data are analyzed for temporal correlation, time spread, and transmission loss and are interpreted in terms of a tomographic system for monitoring the East Sea. 相似文献