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991.
The purpose of this paper is to analyze how a firm responds to a challenge from a transformational technology that poses a threat to its historical business model. We extend Christensen’s theory of disruptive technologies to undertake this analysis. The paper makes two contributions: the first is to extend theory and the second is to learn from the example of Kodak’s response to digital photography. Our extensions to existing theory include considerations of organizational change, and the culture of the organization. Information technology has the potential to transform industries through the creation of new digital products and services. Kodak’s middle managers, culture and rigid, bureaucratic structure hindered a fast response to new technology which dramatically changed the process of capturing and sharing images. Film is a physical, chemical product, and despite a succession of new CEOs, Kodak’s middle managers were unable to make a transition to think digitally. Kodak has experienced a nearly 80% decline in its workforce, loss of market share, a tumbling stock price, and significant internal turmoil as a result of its failure to take advantage of this new technology. 相似文献
992.
Kinsinger CR Apffel J Baker M Bian X Borchers CH Bradshaw R Brusniak MY Chan DW Deutsch EW Domon B Gorman J Grimm R Hancock W Hermjakob H Horn D Hunter C Kolar P Kraus HJ Langen H Linding R Moritz RL Omenn GS Orlando R Pandey A Ping P Rahbar A Rivers R Seymour SL Simpson RJ Slotta D Smith RD Stein SE Tabb DL Tagle D Yates JR Rodriguez H 《Proteomics. Clinical applications》2011,5(11-12):580-589
Policies supporting the rapid and open sharing of proteomic data are being implemented by the leading journals in the field. The proteomics community is taking steps to ensure that data are made publicly accessible and are of high quality, a challenging task that requires the development and deployment of methods for measuring and documenting data quality metrics. On September 18, 2010, the U.S. National Cancer Institute (NCI) convened the "International Workshop on Proteomic Data Quality Metrics" in Sydney, Australia, to identify and address issues facing the development and use of such methods for open access proteomics data. The stakeholders at the workshop enumerated the key principles underlying a framework for data quality assessment in mass spectrometry data that will meet the needs of the research community, journals, funding agencies, and data repositories. Attendees discussed and agreed up on two primary needs for the wide use of quality metrics: (i) an evolving list of comprehensive quality metrics and (ii) standards accompanied by software analytics. Attendees stressed the importance of increased education and training programs to promote reliable protocols in proteomics. This workshop report explores the historic precedents, key discussions, and necessary next steps to enhance the quality of open access data. By agreement, this article is published simultaneously in Proteomics, Proteomics Clinical Applications, Journal of Proteome Research, and Molecular and Cellular Proteomics, as a public service to the research community. The peer review process was a coordinated effort conducted by a panel of referees selected by the journals. 相似文献
993.
Extending 32-bit DX generators introduced by Deng and Xu (ACM Trans Model Comput Simul 13:299–309, 2003), we perform an extensive computer search for classes of 64-bit and 128-bit DX generators of large orders. The period lengths of these high resolution DX generators are ranging from 101915 to 1058221. The software implementation of these generators can be developed for 64-bit or 128-bit hardware. The great empirical performances of DX generators have been confirmed by an extensive battery of tests in the TestU01 package. These high resolution DX generators can be useful to perform large scale simulations in scientific investigations for various computer systems. 相似文献
994.
Malavolta Ivano Muccini Henry Pelliccione Patrizio Tamburri Damien 《IEEE transactions on pattern analysis and machine intelligence》2010,36(1):119-140
Many architectural languages have been proposed in the last 15 years, each one with the chief aim of becoming the ideal language for specifying software architectures. What is evident nowadays, instead, is that architectural languages are defined by stakeholder concerns. Capturing all such concerns within a single, narrowly focused notation is impossible. At the same time, it is also impractical to define and use a “universal” notation, such as UML. As a result, many domain-specific notations for architectural modeling have been proposed, each one focusing on a specific application domain, analysis type, or modeling environment. As a drawback, a proliferation of languages exists, each one with its own specific notation, tools, and domain specificity. No effective interoperability is possible to date. Therefore, if a software architect has to model a concern not supported by his own language/tool, he has to manually transform (and, eventually, keep aligned) the available architectural specification into the required language/tool. This paper presents DUALLy, an automated framework that allows architectural languages and tools interoperability. Given a number of architectural languages and tools, they can all interoperate thanks to automated model transformation techniques. DUALLy is implemented as an Eclipse plugin. Putting it in practice, we apply the DUALLy approach to the Darwin/FSP ADL and to a UML2.0 profile for software architectures. By making use of an industrial complex system, we transform a UML software architecture specification in Darwin/FSP, make some verifications by using LTSA, and reflect changes required by the verifications back to the UML specification. 相似文献
995.
We present a novel hybrid rendering method for diffuse and glossy indirect illumination. A scene is rendered using standard rasterization on a GPU. In a shader, secondary ray queries are used to sample incident light and to compute indirect lighting. We observe that it is more important to cast many rays than to have precise results for each ray. Thus, we approximate secondary rays by intersecting them with precomputed layered depth images of the scene. We achieve interactive to real-time frame rates including indirect diffuse and glossy effects. 相似文献
996.
Because of the complicated shorelines, inaccessibility and vast spread of some lakes, information on changing shorelines is difficult to acquire. A new water index (WI) has been applied to quantify changes in five saline and non‐saline Rift Valley lakes in Kenya using Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper (ETM+) data. The WI is based on a logical combination of the Tasseled Cap Wetness (TCW) index and the Normalized Difference Water Index (NDWI). Using regression analysis with estimated shoreline coordinates, the WI detected the shorelines with an accuracy of 98.4%, which was 22.3% higher than the TCW, and 43.2% more accurate than the NDWI. Change detection was derived using image differencing followed by density slicing and unsupervised classification. The saline lakes (Bogoria, Nakuru and Elementaita) changed more with respect to the ratio of the change in the original surface areas than the non‐saline lakes (Baringo and Naivasha). 相似文献
997.
A new micromixer incorporating integrated electrodes deposited on the bottom surface of a glass/PDMS microchannel is used
to induce a localized, perpendicular electric field within pressure driven axial flow. The presence of the electric field
drives electro-osmotic flow in the transverse direction along the channel walls, creating helical motion that serves to mix
the fluid. A numerical model is used to describe the three-dimensional flow field, where characterization is performed via
particle tracking of passive tracer particles, and the conditional entropy (S
lc) is utilized to approximate the extent of mixing along cross-sectional planes. The geometrical parameters and operating conditions
of the numerical model are used to fabricate an experimental device, and fluorescence microscopy measurements are used to
verify mixing of rhodamine B across the width of the microchannel for a wide range of fluid flow rates. The results demonstrate
that under certain operating conditions and selective placement of the electrode gaps along the width of the microchannel,
efficient mixing can be achieved within 6 mm of the inlet.
相似文献
David S. DandyEmail: |
998.
The magnification factor in transmission electron microscopy is not very precise, hampering for instance quantitative analysis of specimens. Calibration of the magnification is usually performed interactively using replica specimens, containing line or grating patterns with known spacing. In the present study, a procedure is described for automated magnification calibration using digital images of a line replica. This procedure is based on analysis of the power spectrum of Fourier transformed replica images, and is compared to interactive measurement in the same images. Images were used with magnification ranging from 1,000 x to 200,000 x. The automated procedure deviated on average 0.10% from interactive measurements. Especially for catalase replicas, the coefficient of variation of automated measurement was considerably smaller (average 0.28%) compared to that of interactive measurement (average 3.5%). In conclusion, calibration of the magnification in digital images from transmission electron microscopy may be performed automatically, using the procedure presented here, with high precision and accuracy. 相似文献
999.
Flow-Based Image Abstraction 总被引:4,自引:0,他引:4
Kang Henry Lee Seungyong Chui Charles K. 《IEEE transactions on visualization and computer graphics》2009,15(1):62-76
We present a non-photorealistic rendering technique that automatically delivers a stylized abstraction of a photograph. Our approach is based on shape/color filtering guided by a vector field that describes the flow of salient features in the image. This flow-based filtering significantly improves the abstraction performance in terms of feature enhancement and stylization. Our method is simple, fast, and easy to implement. Experimental results demonstrate the effectiveness of our method in producing stylistic and feature-enhancing illustrations from photographs. 相似文献
1000.
Dynamic congestion pricing has become an important research topic because of its practical implications. In this paper, we
formulate dynamic second-best toll pricing (DSBTP) on general networks as a bilevel problem: the upper level is to minimize
the total weighted system travel time and the lower level is to capture motorists’ route choice behavior. Different from most
of existing DSBTP models, our formulation is in discrete-time, which has very distinct properties comparing with its continuous-time
counterpart. Solution existence condition of the proposed model is established independent of the actual formulation of the
underlying dynamic user equilibrium (DUE). To solve the bilevel DSBTP model, we adopt a relaxation scheme. For this purpose,
we convert the bilevel formulation into a single level nonlinear programming problem by applying a link-node based nonlinear
complementarity formulation for DUE. The single level problem is solved iteratively by first relaxing the strick complementarity
by a relaxation parameter, which is then progressively reduced. Numerical results are also provided in this paper to illustrate
the proposed model and algorithm. In particular, we show that by varying travel time weights on different links, DSBTP can
help traffic management agencies better achieve certain system objectives. Examples are given on how changes of the weights
impact the optimal tolls and associated objective function values.
相似文献
Henry X. LiuEmail: |