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991.
992.
Mari Honkanen Maija Hoikkanen Minnamari Vippola Jyrki Vuorinen Toivo Lepistö 《Journal of Materials Science》2011,46(20):6618-6626
The aim of this study was to characterize two different copper grades, oxygen-free copper, and phosphorous deoxidized copper,
with aminofunctional silane layers on them and to study these silane layers as coupling agents in the injection-molded thermoplastic
urethane–copper hybrids. The copper surfaces were as-received and modified, i.e., polished and oxidized. The copper surfaces
and silane layers which were grown from solution concentrations of 0.25 and 0.5 vol% were studied with reflection absorption
infrared spectroscopy (RAIRS), atomic force microscope (AFM), scanning electron microscope (SEM), and transmission electron
microscope (TEM). The adhesive strengths of the copper–polymer joints were measured with peel tests and peeled surfaces were
further studied with RAIRS, AFM, and FESEM. On the as-received copper surface, the silane layer was irregular and existed
mainly in the surface roughness sites. This was the reason why hybrids manufactured with the as-received copper failed mostly
in the silane layer. Hybrids manufactured with the oxidized copper sheets had a uniform silane layer and the hybrids failed
mostly cohesively in thermoplastic urethane and had excellent peel strength values. In all silane-treated copper samples,
Si–O–Si groups were formed confirming the cross-linking in the silane layer. 相似文献
993.
L. Ribić-Zelenović N. Ćirović M. Spasojević N. Mitrović A. Maričić V. Pavlović 《Materials Chemistry and Physics》2012
A nanostructured Ni–Fe–W powder was obtained by electrodeposition from ammonium citrate electrolyte within the current density range of 500–1000 mA cm−2 at the electrolyte temperature of 50 °C–70 °C. XRD analysis shows that the powder contains an amorphous matrix having embedded nanocrystals of the FCC solid solution of iron and tungsten in nickel, with an average crystal grain size of 3.4 nm, a high internal microstrain value and a high density of chaotically distributed dislocations. EDS analysis exhibits that the chemical composition of the Ni–24%Fe–11%W powder does not depend upon current density and electrolyte temperature due to the diffusion control of the process of codeposition of nickel, iron and tungsten. 相似文献
994.
AbstractThis paper discusses the condition and legibility of prehistoric grave mounds and their landscape context and assesses legibility for experts and lay people by combining archaeological landscape analysis and visual historicity landscape analysis. The paper compares, on the one hand, the heritage object with inherited meanings, and on the other, how it is perceived and understood. The results reveal that legibility in archaeological terms and in visual terms sometimes overlap, but sometimes diverge. Divergences occur when visual legibility of a grave mound is high but where the prehistoric context and legibility are changed. In situations where the context of the mound is preserved and legibility of the mound is high in visual terms, the two overlap. At the fringe, the monuments were mostly both non-visible and had a changed context. Accepting that the prehistoric context has changed, within landscape planning and heritage management, recognising cultural heritage as features in the present-day landscape can be one way forward in urban fringe areas. 相似文献
995.
Gerhold Marcus Hartmanns Arnd Stoelinga Mariëlle 《Innovations in Systems and Software Engineering》2019,15(3-4):207-233
Innovations in Systems and Software Engineering - Many systems are inherently stochastic: they interact with unpredictable environments or use randomised algorithms. Classical model-based testing... 相似文献
996.
Jada Ravi Mari Annadhasan Avulu Vinod Kumar Rajadurai Chandrasekar 《Advanced functional materials》2021,31(25):2100642
Fabrication of microscale organic photonic integrated circuits (μ-OPIC) from two electronically different flexible crystals via a mechanophotonics approach is demonstrated here. The experiments focus on the mechanical micromanipulation of orange-emitting (E)-1-(4-(dimethylamino)-phenyl)iminomethyl-2-hydroxyl-naphthalene (DPIN) and green-emitting (E)-1-(4-bromo)iminomethyl-2-hydroxyl-naphthalene (BPIN) crystals with atomic force cantilever tip. The flexibility of these crystals originate from molecular H-bonding, C H∙∙∙π, and π···π stacking interactions. These mechanically compliant crystals form exceedingly bent and photonically relevant reconfigurable geometries during micromanipulation, including three μ-OPICs. Remarkably, these μ-OPICs operate through passive-, active-waveguiding and energy transfer mechanisms. Depending upon the crystal's electronic nature (either BPIN or DPIN) receiving the optical signal input, the circuit executes mechanism-selective and direction-specific optical outputs. The presented proof-of-principle concepts can be used to fabricate complex photonic circuits with diverse, flexible crystals performing multiple optical functions. 相似文献
997.
Márton Deák Tamás Telbisz Mátyás Árvai László Mari Ferenc Horváth Balázs Kohán 《International journal of remote sensing》2017,38(18):5215-5231
Hyperspectral satellite data is an efficient tool in vegetation mapping; however, previous studies indicate that classifying heterogeneous forests might be difficult. In this study, we propose a mapping method for a heterogeneous forest using the data of the Earth Observing-1 (EO-1) Hyperion supplemented by field survey. We introduced a band reduction method to raise classification accuracy of the Support Vector Machine classification algorithm and compared the results to the one reduced by principal component analysis (PCA), stepwise discriminant analysis (SDA), and the original data set. We also used a modified version of the Vegetation–Impervious–Soil model to create mixed vegetation classes consisting of the commonly mixing species in the area and classified them using Decision Tree classification method. We managed to achieve 84.28% approximately using our band reduction method which is 2.36% increase compared to PCA (81.92%), 1.43% compared to the SDA (82.85%), and 7.61% compared to the original data set (76.67%). Introducing the mixed vegetation classes raised the overall accuracy even higher (85.79%). 相似文献
998.
Ryusuke Egawa Kazuhiko Komatsu Shintaro Momose Yoko Isobe Akihiro Musa Hiroyuki Takizawa Hiroaki Kobayashi 《The Journal of supercomputing》2017,73(9):3948-3976
Achieving a high sustained simulation performance is the most important concern in the HPC community. To this end, many kinds of HPC system architectures have been proposed, and the diversity of the HPC systems grows rapidly. Under this circumstance, a vector-parallel supercomputer SX-ACE has been designed to achieve a high sustained performance of memory-intensive applications by providing a high memory bandwidth commensurate with its high computational capability. This paper examines the potential of the modern vector-parallel supercomputer through the performance evaluation of SX-ACE using practical engineering and scientific applications. To improve the sustained simulation performances of practical applications, SX-ACE adopts an advanced memory subsystem with several new architectural features. This paper discusses how these features, such as MSHR, a large on-chip memory, and novel vector processing mechanisms, are beneficial to achieve a high sustained performance for large-scale engineering and scientific simulations. Evaluation results clearly indicate that the high sustained memory performance per core enables the modern vector supercomputer to achieve outstanding performances that are unreachable by simply increasing the number of fine-grain scalar processor cores. This paper also discusses the performance of the HPCG benchmark to evaluate the potentials of supercomputers with balanced memory and computational performance against heterogeneous and cutting-edge scalar parallel systems. 相似文献
999.
This longitudinal study looks at the metaphors used in a public sector information systems development project from the perspective of cognitive metaphor theory (Lakoff & Johnson, 1980 ). We examine the use of metaphors by project team members, including representatives of the users, software developers and the managers guiding the project work. The findings indicate that project team members and managers use a rich set of metaphors to make sense of the project and the records management system they are working on. Notably, distinct sets of metaphors are used in different project phases and among the project personnel and management. As the differences in the metaphors also coincide with key events in the trajectory of the project, we contend that metaphors have significant power in sensemaking, influencing action and project outcomes. In particular, we find that in highly ambiguous, knowledge‐intensive situations, metaphor use with unclear intentions and purpose hinders learning and creates more chaos than order. From a practical perspective, our study highlights the relevance of metaphor use for project management. We suggest that intentional selection of metaphors by management could be beneficial for many complex information systems projects. © 2016 John Wiley & Sons Ltd 相似文献
1000.
Fábio Pittoli Henrique Damasceno Vianna Jorge Luis Victória Barbosa Emerson Butzen Mari Ângela Gaedke Juvenal Soares Dias da Costa Renan Belarmino Scherer dos Santos 《Telematics and Informatics》2018,35(5):1222-1236
Noncommunicable diseases are the main reason to the rise of diseases incidence in the developed world. The management and prevention of these diseases can be done by controlling the behavioral and biological risk factors which are related to them. ChronicPrediction is an intelligent system for noncommunicable diseases care which determines in real time the impact on risk factors due to actions taken by users. Based on impact information, the system presents on users’ smartphones strategic messages to help in their treatment. ChronicPrediction applies Bayesian Networks (BNs) which use risk factors for mapping the causes of noncommunicable diseases worsening. The support to multiple chronic diseases and the integrated use of multiple BNs based on risk factors are the main contributions of this work and differentiate the proposed system from related work. We have built a functional prototype that allowed us to conduct two experiments. The first one successfully tested the main functionalities provided by ChronicPrediction to support BNs based on risk factors and the sending of messages to users’ smartphones. The evaluation involved the building of a BN for predicting coronary artery disease made with real world data obtained in a prospective cohort study. The study involved 302 patients from a hospital localized in southern Brazil. The second experiment assessed the ChronicPrediction support to multiple BNs at same time. The test involved the previous BN and another from a thirty part research work to map risk factors of diabetes. The results were encouraging and show potential for implementing ChronicPrediction in real-life situations. 相似文献