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排序方式: 共有131条查询结果,搜索用时 93 毫秒
21.
Po-Shin Huang Li-Hsing Shih Ph.D. 《International Journal of Environmental Science and Technology》2009,6(1):35-50
Owing to the green revolution, environmental problems have now become some of the most important issues worldwide. Environmental knowledge management, which combines the strengths of environmental management and knowledge management, will become a popular tool for businesses in the near future. In this paper, through interviews of staff at different levels and in different departments of the business, i. e. managers and engineers and using the environmental knowledge circulation process, the authors evaluate the success of environmental knowledge management when applied to China Steel Corporation in Taiwan. From the case study, the authors found that China Steel Corporation has applied the environmental knowledge circulation process for over thirty years. The company continually improves its environmental and financial performance through environmental knowledge creation, environmental knowledge accumulation, environmental knowledge sharing, environmental knowledge utilization and environmental knowledge internalization. Water pollution and air emissions have reduced year on year and total energy consumption has reduced by 20 % from 1979 to 2006. On the other hand, China Steel Corporation also makes a profit and reduces cost through energy sold, by-products and recycling. Continuous improvement in environmental knowledge management has rendered China Steel Corporation in the most profitable steel company in Taiwan and the world’s twenty fifth largest steel producing company in 2006. 相似文献
22.
Because a conventional isolation system with constant isolation frequency is usually a long‐period dynamic system, its seismic response is likely to be amplified in earthquakes with strong long‐period wave components, such as near‐fault ground motions. Seismic isolators with variable mechanical properties may provide a promising solution to alleviate this problem. To this end, in this work sliding isolators with variable curvature (SIVC) were studied experimentally. An SIVC isolator is similar to a friction pendulum system (FPS) isolator, except that its sliding surface has variable curvature rather being spherical. As a result, the SIVC's isolation stiffness that is proportional to the curvature becomes a function of the isolator displacement. By appropriately designing the geometry of the sliding surface, the SIVC is able to possess favorable hysteretic behavior. In order to prove the applicability of the SIVC concept, several prototype SIVC isolators, whose sliding surfaces are defined by a sixth‐order polynomial function, were fabricated and tested in this study. A cyclic element test on the prototype SIVC isolators and a shaking table test on an SIVC isolated steel frame were all conducted. The results of both tests have verified that the prototype SIVC isolators do indeed have the hysteretic property of variable stiffness as prescribed by the derived formulas in this study. Moreover, it is also demonstrated that the proposed SIVC is able to effectively reduce the isolator drift in a near‐fault earthquake with strong long‐period components, as compared with that of an FPS system with the same friction coefficient. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
23.
L. H. Shih T. Y. Chou 《International Journal of Environmental Science and Technology》2011,8(3):523-532
Although solar power systems are considered as one of the most promising renewable energy sources, some uncertain factors as well as the high cost could be barriers which create customer resistance. Leasing instead of purchase, as one type of product service system, could be an option to reduce consumer concern on such issues. This study focuses on consumer concerns about uncertainty and willingness to pay for leasing solar power systems. Conjoint analysis method is used to find part worth utilities and estimate gaps of willingness to pay between attribute levels, including various leasing time lengths. The results show the part worth utilities and relative importance of four major attributes, including leasing time. Among concerns about uncertainties, government subsidy, electricity price, reliability, and rise of new generation solar power systems were found to be significantly related to the additional willingness-to-pay for a shorter leasing time. Cluster analysis is used to identify two groups standing for high and low concerns about uncertainty. People with more concerns tend to pay more for a shorter lease time. 相似文献
24.
David Ching-Fang Shih Yih-Min Wu Gwo-Fong Lin Jyr-Ching Hu Yue-Gau Chen Chien-Hsin Chang 《Stochastic Environmental Research and Risk Assessment (SERRA)》2008,22(3):401-410
A transition and subduction zone adjacent to the Ryukyu Arc, Ryukyu Trench, and Okinawa Trough, extends between southern Japan
and northeastern Taiwan. It is generated during the northwestward subduction of the Philippine Sea Plate, which lies the Eurasian
Plate along the Ryukyu Trench. The movement of the Philippine Sea Plate is hindered at the northeastern corner of Taiwan,
which causes complicated structure of the Philippine Sea Plate at the western end of the Ryukyu subduction zone. Development
of the active subduction and transition boundary near the western Ryukyu Arc is evaluated statistically by using displacements
derived from GPS site data. The statistical model shows that the absolute displacement derived from GPS measurements of nearly
8 years indicates a maximum spatial variation of 0.625 m. Three trends are observed for such long-term progress, and use of
linear regression also reveals quite good consistency between the data and statistic models. Such rate is also elevated following
the trend development. Southeastern and nearly horizontal movement is suggested to the main development of for the site movements,
it is likely related to the tensional activity adjacent to this boundary. 相似文献
25.
David Ching-Fang Shih Yue-Gau Chen Gwo-Fong Lin Yih-Min Wu 《Stochastic Environmental Research and Risk Assessment (SERRA)》2009,23(5):613-620
It is evident that the hydrodynamic dispersion coefficient and linear flow velocity dominate solute transport in aquifers.
Both of them play important roles characterizing contaminant transport. However, by definition, the parameter of contaminant
transport cannot be measured directly. For most problems of contaminant transport, a conceptual model for solute transport
generally is established to fit the breakthrough curve obtained from field testing, and then suitable curve matching or the
inverse solution of a theoretical model is used to determine the parameter. This study presents a one-dimensional solute transport
problem for slug injection. Differential analysis is used to analyze uncertainty propagation, which is described by the variance
and mean. The uncertainties of linear velocity and hydrodynamic dispersion coefficient are, respectively, characterized by
the second-power and fourth-power of the length scale multiplied by a lumped relationship of variance and covariance of system
parameters, i.e. the Peclet number and arrival time of maximum concentration. To validate the applicability for evaluating
variance propagation in one-dimensional solute transport, two cases using field data are presented to demonstrate how parametric
uncertainty can be caught depending on the manner of sampling. 相似文献
26.
Storage in confined aquifer: Spectral analysis of groundwater in responses to Earth tides and barometric effect 下载免费PDF全文
David Ching‐Fang Shih 《水文研究》2018,32(12):1927-1935
Dilatation of aquifer and associated water level fluctuation in groundwater well is known to be driven periodically from lunar, solar, or other tidal forces. Time‐dependent variables in groundwater system, such as water level, can be converted to power spectra in the frequency domain using Fourier transform to evaluate significant fluctuation. The major innovation of this research is to develop spectral representation in frequency domain for the groundwater system that the storage in confined aquifer can be determined considering dilatation affected by Earth tides and barometric effect. In order to verify applicability of the evolved method, time series of Earth tides and barograph are collected; aquifer storage is then determined inversely by selecting significant semidiurnal and diurnal components in spectra computation. It suggests that to discover groundwater storage using groundwater level with barograph and tidal potential of Earth in frequency domain becomes accessible and feasible. 相似文献
27.
We present an automatic solar filament detection algorithm based on image enhancement, segmentation, pattern recognition,
and mathematical morphology methods. This algorithm cannot only detect filaments, but can also identify spines, footpoints,
and filament disappearances. It consists of five steps: (1) The stabilized inverse diffusion equation (SIDE) is used to enhance
and sharpen filament contours. (2) A new method for automatic threshold selection is proposed to extract filaments from local
background. (3) The support vector machine (SVM) is used to differentiate between sunspots and filaments. (4) Once a filament
is identified, morphological thinning, pruning, and adaptive edge linking methods are used to determine the filament properties.
(5) Finally, we propose a filament matching method to detect filament disappearances. We have successfully applied the algorithm
to Hα full-disk images obtained at Big Bear Solar Observatory (BBSO). It has the potential to become the foundation of an
automatic solar filament detection system, which will enhance our capabilities of forecasting and predicting geo-effective
events and space weather. 相似文献
28.
Tsung‐Ren Peng Chung‐Ho Wang Shih‐Meng Hsu Nai‐Chin Chen Tai‐Wei Su Jiin‐Fa Lee 《水文研究》2012,26(3):345-355
This study employs stable oxygen and hydrogen isotopes as natural tracers to assess the headwater of a landslide next to a drainage divide and the importance of the slope's headwater in the study area. The study is undertaken near Wu‐She Township in the mountains of central Taiwan. Because a reservoir is located on the other side of the divide, this study evaluates the relationship between the reservoir water and headwater of the landslide as well. Over a 1‐year period, water samples from September 2008 to September 2009, including local precipitation (LP), Wu‐She Reservoir's water (WSRW), slope groundwater (SGW), upper‐reach stream water (USTW), and down‐reach stream water (DSTW), were analysed for deuterium (δD) and oxygen (δ18O) stable isotopes. Results indicate that WSRW is the predominant component in SGW: approximately 70% of SGW originates from WSRW and 30% from LP based on a two end‐member mass‐balance mixing model for δ18O. The similar two end‐member mixing model is also employed to assess the contributions of USTW and SGW to DSTW. Model results indicate that SGW is the major source of DSTW with a contribution of about 67%. Accordingly, about 47% of DSTW sources from the WSRW. In short, owing to reservoir leakage, WSRW contributes the greater part of both SGW and DSTW. Plentiful WSRW in SGW threatens the stability of the slope in the divide area. To avoid subsequent continuous slope failure, necessary mitigation steps are required. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
29.
Natural Hazards - Keelung Port is one of the international commercial ports in Northern Taiwan. In 1867, a tsunami hit the Port, causing hundreds of casualties. In order to minimize the impact of... 相似文献
30.
大气校正对SPOT卫星遥测水质的影响 总被引:1,自引:0,他引:1
藉由卫星遥测进行河川水质监测,目前尚没有较明确可行之方法,如何利用较为简单且适当的SPOT卫星遥测大气校正方法,正确辨识水体水质,是本研究的主要目的。利用SPOT卫星作两阶段非监督式及监督式自动分类,确认卫星影像中水质测站对应之水体样本,并将所有样本依季节分群,俾让卫星监测水体水质样本较为均质。模拟方式采用多变量回归、类神经网络及判别分析3种模式,并比较4种不同之大气校正程序。结果发现。以水质及其指标整体预测来看,类神经网络预测结果较优于多变量回归及判别分析的结果,大气校正方法以直接采用灰度值并消除最暗像元灰度值之校正方法,即可达到不错之预测结果。综合而言,以SPOT或分辨率更高之卫星光谱遥测水质是简单可行,但仍需更多数据以验证其精确度。 相似文献