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991.
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993.
Ugo Becciani Vincenzo Antonuccio-Delogu Alessandro Costa Catia Petta 《Journal of Grid Computing》2012,10(2):265-277
While new infrastructures for large computational challenges begin to be widely accessible to researchers, computational codes
need to be re-designed to exploit new facilities. The Grid and the cloud computing concepts are changing the computational
resource distribution and availability, and much effort start to be made to develop new codes for a better exploitation of
new resources. This paper presents an example of the use of Grid resources, based on gLite middleware, to run cosmological
simulations, that, up to now, are normally executed on Supercomputers. We have also used the Grid to explore and visualize
the dataset. We discuss non particular the performance of FLY a parallel code implementing the octal-tree algorithm introduced
by J. Barnes and P. Hut to compute the gravitational field efficiently. It simulates the evolution of the collisionless component
of the material content of our Universe. FLY was originally developed to run on mainframe systems using the one-side communication
paradigm, but we are now presenting a modified version of the computational algorithm to exploit the Grid environment. We
also integrated the data exploration and visualization process on the Grid, to obtain preliminary results using the distributed
facilities. 相似文献
994.
Most complex information systems are event driven: each part of the system reacts to the events happening in the other parts, potentially generating new events. Complex event processing (CEP) engines in charge of interpreting, filtering, and combining primitive events to identify higher level composite events according to a set of rules are the new breed of message-oriented middleware, which is being proposed today to better support event-driven interactions. 相似文献
995.
Paolo Colomba Simona Fontana Giuseppe Salemi Marilisa Barranca Claudia Lo Sicco Maria Antonietta Mazzola Paolo Ragonese Giovanni Savettieri Giacomo De Leo Riccardo Alessandro Giovanni Duro 《International journal of molecular sciences》2014,15(12):23269-23282
Multiple sclerosis (MS) is an autoimmune inflammatory demyelinating disease of the central nervous system. At present, the molecular mechanisms causing the initiation, development and progression of MS are poorly understood, and no reliable proteinaceous disease markers are available. In this study, we used an immunoproteomics approach to identify autoreactive antibodies in the cerebrospinal fluid of MS patients to use as candidate markers with potential diagnostic value. We identified an autoreactive anti-transferrin antibody that may have a potential link with the development and progression of MS. We found this antibody at high levels also in the serum of MS patients and created an immunoenzymatic assay to detect it. Because of the complexity and heterogeneity of multiple sclerosis, it is difficult to find a single marker for all of the processes involved in the origin and progression of the disease, so the development of a panel of biomarkers is desirable, and anti-transferrin antibody could be one of these. 相似文献
996.
Michele SalePiervincenzo Rizzo Alessandro Marzani 《Mechanical Systems and Signal Processing》2011,25(6):2241-2256
In this study an inverse procedure based on the propagation of guided ultrasonic waves is proposed for the characterization of the elastic material constants of plates. The procedure consists of an optimization problem in which the discrepancy between the dispersion curves obtained through a semi analytical finite element (SAFE) formulation and numerical or experimental dispersion curves is minimized. The numerical dispersion curves were obtained from the application of the commercial finite element analysis software ANSYS. Finally experimental data were obtained by adopting a hybrid broadband laser/PZT ultrasonic set-up in a pitch-catch configuration. For both numerical and experimental data, the joint time-frequency analysis of the continuous wavelet transform was used.The optimization scheme proposed in this study is based on an improved version of the simplex search method. The scheme inputs an initial guess of the material parameters in the SAFE formulation. The values of these parameters are iteratively updated until the discrepancy between the SAFE-based group velocity dispersion curves and the numerical or experimental curves is minimized. The scheme is designed to minimize the discrepancy associated with the lowest symmetric and anti-symmetric order mode simultaneously.The validity of the SAFE method coupled to the inverse procedure scheme is tested to characterize the elastic material properties of a 2.54 mm thick aluminum plate. As the SAFE formulation is valid for waveguides of arbitrary cross-section the paper represents the first step toward the integration of an inversion scheme applicable into the SAFE algorithm to characterize the material properties of waveguides of complex geometries and various boundary conditions. 相似文献
997.
Renato Queiroz Assis Carlos Henrique Pagno Tania Maria Haas Costa Simone Hickmann Fl?res Alessandro de Oliveira Rios 《软包装商情》2018,(3)
β-胡萝卜素可能是一种优良的天然抗氧化剂,可能有助于纳米封装新技术的发展为主动包装添加抗氧化剂。这项工作的目的是开发加自由β-胡萝卜素或β-胡萝卜素胶囊和与聚合物基体的相互作用的评估活动的可生物降解薄膜。结果表明,生物活性化合物可以作为天然抗氧化剂和疏水活性可降解包装维护食品安全添加。 相似文献
998.
Svetlana V. Malysheva Séverine Goscinny Govindan Malarvannan Giulia Poma Mirjana Andjelkovic Stefan Voorspoels 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2018,35(2):292-304
An ultra-high performance liquid chromatography – tandem mass spectrometry (UHPLC-MS/MS) method was developed and validated (in-house) for the quantification of selected brominated flame retardants (BFRs), including tetrabromobisphenol A (TBBPA), hexabromocyclododecanes (HBCDs), tetrabromobisphenol S (TBBPS) and bromophenols (BPs), in various food matrices. The sample preparation consisted of extraction of TBBPS with acidified acetonitrile followed by a fast dispersive solid-phase extraction (dSPE) clean-up and extraction of the other BFRs with a mixture of hexane and dichloromethane (1:1, v/v) with subsequent clean-up using acidified silica (44%, w/w). The limits of quantification of the method varied widely for the types of food matrices and the different classes of BFRs from 4 pg g?1 wet weight (ww) to 8 ng g?1 ww. For most of the analytes the apparent recovery was in the range 70–120%, and the method precision (under repeatability conditions) was below 20%. The method was successfully applied in proficiency testing exercises as well as for analysis of various food items. Only 25% of the collected food samples contained BFRs, with 4-bromophenol and α-HBCD as the only detected compounds. The contaminated foodstuffs were fish and eggs with concentrations in the range from 48 to 305 pg g?1 ww. 相似文献
999.
Nowadays, manufacturing firms are dealing with the unpredictability of market requirements and the frequent changes induced by technological innovation. For this reason, firms are more and more addressing the need to be responsive at an affordable cost. To do so, they are required to develop a capability called reconfigurability. This paper is a review of the existing literature because the current need makes interesting to reflect on the state of the art of reconfigurability as a concept. This reflection has led to focus on reconfigurability characteristics for both their relevance and their relationships with managerial decisions in manufacturing. To this end, a framework has been proposed. It is based on system lifecycle and production levels. These two elements have been deduced from literature and identified as relevant dimensions for decision-making. 相似文献
1000.
In recent years, the performance of deep neural networks (DNNs) is significantly improved, making them suitable for many application fields, such as autonomous driving, advanced robotics, and industrial control. Despite a lot of research being devoted to improving the accuracy of DNNs, only limited efforts have been spent to enhance their timing predictability, required in several real-time applications. This paper proposes a software infrastructure based on the Linux operating system to integrate DNNs within a real-time multicore system. It has been realized by modifying both the internal scheduler of the popular TensorFlow framework and the SCHED_DEADLINE scheduling class of Linux. The proposed infrastructure allows providing timing isolation of DNN inference tasks, hence improving the determinism of the temporal interference generated by TensorFlow. The proposal is finally evaluated with a case study derived from a state-of-the-art benchmark inspired by an autonomous industrial system. Extensive experiments demonstrate the effectiveness of the proposed solution and show a significant reduction of both average and longest-observed response times of TensorFlow tasks. 相似文献