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41.
Cake filtration theory and practice 总被引:2,自引:0,他引:2
Ernest Mayer 《Chemical engineering journal (Lausanne, Switzerland : 1996)》2000,80(1-3):233-236
42.
Ernest C. Njau 《Renewable Energy》2000,19(4)
It is shown analytically that if f0 represents the frequency of the 11-year sunspot cycle or that of the 22-year sunspot cycle or that of the 35- to 40-year sunspot cycle or that of the seasonal cycle, then large heat/temperature oscillations should exist in the surface–atmosphere system (SAS) at frequencies , , and 2f0. Also if f0 represents the frequency of the seasonal cycle alone, then large heat/temperature oscillations should exist in the SAS not only at the frequencies listed above but also at the additional frequencies and . Actual existence of heat/temperature oscillations in the SAS at the frequencies given above has been amply verified by means of past temperature records. Furthermore, we illustratively show that both the 11-year sunspot cycle and corresponding heat/temperature oscillations in the SAS at a period of 11 years maintain approximately stable phase relationships with each other as long as each of the latter oscillations steadily keeps to one amplitude–modulation state. The phase relationship may change if the heat/temperature oscillation involved switches into a different amplitude–modulation state. One of the spin-offs of the analysis reported herein is a realisation that the quasi-biennial oscillation is apparently composed of individual components at periods , 2 and 3 years. 相似文献
43.
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45.
Xiao-Ming Xiong Ernest S. Kuh 《International Journal of Circuit Theory and Applications》1990,18(4):411-430
We present a new geometric approach to VLSI layout compaction in this paper. In contrast to existing compaction algorithms, we rely on the geometric method and bypass both compaction grids and constraint graphs during the entire compaction process. A systematic and efficient way is introduced to enumerate all possible jogs. For the given layout topology we prove that the geometric algorithm yields the minimum-area layout in one-dimensional compaction with automatic jog insertion. In the final output, only necessary jogs are inserted and the total wire length is minimized as a secondary goal. Furthermore, the integration of local compaction tools into a layout CAD system and the practical extensions of our algorithm are addressed. 相似文献
46.
Recent advances in image reconstruction, coil sensitivity calibration, and coil array design for SMASH and generalized parallel MRI. 总被引:4,自引:0,他引:4
Daniel K Sodickson Charles A McKenzie Michael A Ohliger Ernest N Yeh Mark D Price 《Magma (New York, N.Y.)》2002,13(3):158-163
Parallel magnetic resonance imaging (MRI) techniques use spatial information from arrays of radiofrequency (RF) detector coils to accelerate imaging. A number of parallel MRI techniques have been described in recent years, and numerous clinical applications are currently being explored. The advent of practical parallel imaging presents various challenges for image reconstruction and RF system design. Recent advances in tailored SiMultaneous Acquisition of Spatial Harmonics (SMASH) image reconstructions are summarized. These advances enable robust SMASH imaging in arbitrary image planes with a wide range of coil array geometries. A generalized formalism is described which may be used to understand the relations between SMASH and SENSE, to derive typical implementations of each as special cases, and to form hybrid techniques combining some of the advantages of both. Accurate knowledge of coil sensitivities is crucial for parallel MRI, and errors in calibration represent one of the most common and the most pernicious sources of error in parallel image reconstructions. As one example, motion of the patient and/or the coil array between the sensitivity reference scan and the accelerated acquisition can lead to calibration errors and reconstruction artifacts. Self-calibrating parallel MRI approaches that address this problem by eliminating the need for external sensitivity references are reviewed. The ultimate achievable signal-to-noise ratio (SNR) for parallel MRI studies is closely tied to the geometry and sensitivity patterns of the coil arrays used for spatial encoding. Several parallel imaging array designs that depart from the traditional model of overlapped adjacent loop elements are described. 相似文献
47.
Prof. Dr. K. C. Nicolaou Derek Rhoades Dr. Yanping Wang Dr. Sotirios Totokotsopoulos Dr. Ruoli Bai Dr. Ernest Hamel 《ChemMedChem》2015,10(12):1974-1979
The design, synthesis, and biological evaluation of a series of epothilone analogues with novel side chains equipped with an amino group are described. Their design facilitates potential conjugation to selective drug delivery systems such as antibodies. Their synthesis proceeded efficiently via Stille coupling of a readily available vinyl iodide and heterocyclic stannanes. Cytotoxicity studies and tubulin binding assays revealed two of these analogues to be more potent than epothilones A–D and the anticancer agent ixabepilone, currently in clinical use. 相似文献
48.
This paper investigates the fundamental difference between a simple e-tender box and a traditional physical tender box, and
highlights a series of security traps created by the functional differences. Based on our findings, we have defined the security
requirements for an e-tender submission protocol. We also discuss functional limitations of cryptographic technologies. As
a result, two secure e-tender submission protocols are proposed which enable a secure e-tender submission. Protocols are assumed
to run under the condition that all tendering parties (principal and tenderers) are dishonest players. Our informal and formal
security analysis show that these protocols meet their security goals under well known collusion scenarios. Because security
is a process not a product, our approach will have broad industry application for developing secure electronic business processes
in areas other than e-tendering.
相似文献
Colin BoydEmail: |
49.
Corby Brooke C.; Hodges Ernest V. E.; Perry David G. 《Canadian Metallurgical Quarterly》2007,43(1):261
The generality of S. K. Egan and D. G. Perry's (2001) model of gender identity and adjustment was evaluated by examining associations between gender identity (felt gender typicality, felt gender contentedness, and felt pressure for gender conformity) and social adjustment in 863 White, Black, and Hispanic 5th graders (mean age = 11.1 years). Relations between gender identity and adjustment varied across ethnic/racial groups, indicating that S. K. Egan and D. G. Perry's model requires amendment. It is suggested that the implications of gender identity for adjustment depend on the particular meanings that a child attaches to gender (e.g., the specific attributes the child regards as desirable for each sex); these meanings may vary across and within ethnic/racial groups. Cross-ethnic/racial investigation can aid theory building by pointing to constructs that are neglected in research with a single ethnic/racial group but that are crucial components of basic developmental processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
50.
Wuchen Li Ernest K. Ryu Stanley Osher Wotao Yin Wilfrid Gangbo 《Journal of scientific computing》2018,75(1):182-197
We propose a new algorithm to approximate the Earth Mover’s distance (EMD). Our main idea is motivated by the theory of optimal transport, in which EMD can be reformulated as a familiar \(L_1\) type minimization. We use a regularization which gives us a unique solution for this \(L_1\) type problem. The new regularized minimization is very similar to problems which have been solved in the fields of compressed sensing and image processing, where several fast methods are available. In this paper, we adopt a primal-dual algorithm designed there, which uses very simple updates at each iteration and is shown to converge very rapidly. Several numerical examples are provided. 相似文献