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排序方式: 共有1130条查询结果,搜索用时 15 毫秒
91.
Douglas F. G. Santiago Renato Portugal Nolmar Melo 《Quantum Information Processing》2013,12(5):1871-1884
It is known that nonadditive quantum codes can have higher code dimensions than stabilizer codes for the same length and minimum distance. The class of codeword stabilized codes (CWS) provides tools to obtain new nonadditive quantum codes by reducing the problem to finding nonlinear classical codes. In this work, we establish some results on the kind of non-Pauli operators that can be used as observables in the decoding scheme of CWS codes and propose a procedure to obtain those observables. 相似文献
92.
An I&I‐Based Observer to Solve the Output‐Feedback Synchronization Problem for a Class of Chaotic Systems 下载免费PDF全文
Carlos Aguilar‐Ibañez Eloísa García‐Canseco Rafael Martínez‐García Juan Carlos Martínez‐García Miguel Santiago Suarez‐Castañon 《Asian journal of control》2018,20(4):1491-1503
A novel robust observer, intended to solve the output‐feedback chaos synchronization problem for the Master/Slave Configuration, is proposed here. Assuming that the given Master system belongs to a specific class of feedback‐linearized systems, our solution is based on the well‐known Immersion and Invariance (I&I) method. The proposed observer is devoted to the asymptotic estimation of the Master system's underlying dynamics, and its effectiveness is illustrated via computer‐based simulations that involve both the so‐called Duffing's oscillator and the Genesio & Tesi system. 相似文献
93.
Santiago Huerta 《Nexus Network Journal》2007,9(2):211-248
An oval dome may be defined as a dome whose plan or profile (or both) has an oval form. The word “oval” comes from the Latin
ovum, egg. The present paper contains an outline of the origin and application of the oval in historical architecture; a discussion
of the spatial geometry of oval domes, that is, the different methods employed to lay them out; a brief exposition of the
mechanics of oval arches and domes; and a final discussion of the role of geometry in oval arch and dome design. 相似文献
94.
Miguel Martínez-Espronceda Jesús D. Trigo Santiago Led H. Gilberto Barrón-González Javier Redondo Alfonso Baquero Luis Serrano 《Computer methods and programs in biomedicine》2014
Experiences applying standards in personal health devices (PHDs) show an inherent trade-off between interoperability and costs (in terms of processing load and development time). Therefore, reducing hardware and software costs as well as time-to-market is crucial for standards adoption. The ISO/IEEE11073 PHD family of standards (also referred to as X73PHD) provides interoperable communication between PHDs and aggregators. Nevertheless, the responsibility of achieving inexpensive implementations of X73PHD in limited resource microcontrollers falls directly on the developer. Hence, the authors previously presented a methodology based on patterns to implement X73-compliant PHDs into devices with low-voltage low-power constraints. That version was based on multitasking, which required additional features and resources. This paper therefore presents an event-driven evolution of the patterns-based methodology for cost-effective development of standardized PHDs. The results of comparing between the two versions showed that the mean values of decrease in memory consumption and cycles of latency are 11.59% and 45.95%, respectively. In addition, several enhancements in terms of cost-effectiveness and development time can be derived from the new version of the methodology. Therefore, the new approach could help in producing cost-effective X73-compliant PHDs, which in turn could foster the adoption of standards. 相似文献
95.
A. C. H. Barreto F. J. N. Maia V. R. Santiago V. G. P. Ribeiro J. C. Denardin Giuseppe Mele L. Carbone Diego Lomonaco S. E. Mazzetto P. B. A. Fechine 《Microfluidics and nanofluidics》2012,12(5):677-686
In this work, we present the synthesis and characterization of a new surfactant molecule obtained from a byproduct of the cashew nut processing (diphosphorylated cardol, DPC). It is herein used to overcoat magnetic nanoparticles showing spinel structures in order to create new ferrofluids. The nanoparticle structure and magnetic properties have been deeply investigated. DPC-functionalized Fe3O4 and NiFe2O4 samples exhibit higher magnetic saturation than DPC–CoFe2O4. These new ferrofluids reveal appealing as possible nanoparticle stabilizing molecules, magnetic resonance imaging agents, storage systems or in any material science field that requires the employment of biocompatible magnetic stable fluids. 相似文献
96.
The explanation of certain 3D concepts is based on 2D drawings. These drawings should contain certain depth cues, such as perspective and overlapping. Until recently, parallax has not been used as a depth cue. Nevertheless, new technologies allow it to be incorporated. This forms the background to our study of the design of interactive educational resources and stereoscopic graphics. The results obtained demonstrate that (1) the use of parallax cues improves the interpretation of the figures and (2) that the assistance they afford is most appreciated by the students with less highly developed spatial perception. 相似文献
97.
Jesús M. Hermida Santiago Meliá Andrés Montoyo Jaime Gómez 《Information Systems Frontiers》2013,15(3):411-431
Business Intelligence (BI) applications have been gradually ported to the Web in search of a global platform for the consumption and publication of data and services. On the Internet, apart from techniques for data/knowledge management, BI Web applications need interfaces with a high level of interoperability (similar to the traditional desktop interfaces) for the visualisation of data/knowledge. In some cases, this has been provided by Rich Internet Applications (RIA). The development of these BI RIAs is a process traditionally performed manually and, given the complexity of the final application, it is a process which might be prone to errors. The application of model-driven engineering techniques can reduce the cost of development and maintenance (in terms of time and resources) of these applications, as they demonstrated by other types of Web applications. In the light of these issues, the paper introduces the Sm4RIA-B methodology, i.e., a model-driven methodology for the development of RIA as BI Web applications. In order to overcome the limitations of RIA regarding knowledge management from the Web, this paper also presents a new RIA platform for BI, called RI@BI, which extends the functionalities of traditional RIAs by means of Semantic Web technologies and B2B techniques. Finally, we evaluate the whole approach on a case study—the development of a social network site for an enterprise project manager. 相似文献
98.
99.
100.
François Waldner Diego De Abelleyra Santiago R. Verón Miao Zhang Bingfang Wu Dmitry Plotnikov 《International journal of remote sensing》2016,37(14):3196-3231
Accurate cropland information is of paramount importance for crop monitoring. This study compares five existing cropland mapping methodologies over five contrasting Joint Experiment for Crop Assessment and Monitoring (JECAM) sites of medium to large average field size using the time series of 7-day 250 m Moderate Resolution Imaging Spectroradiometer (MODIS) mean composites (red and near-infrared channels). Different strategies were devised to assess the accuracy of the classification methods: confusion matrices and derived accuracy indicators with and without equalizing class proportions, assessing the pairwise difference error rates and accounting for the spatial resolution bias. The robustness of the accuracy with respect to a reduction of the quantity of calibration data available was also assessed by a bootstrap approach in which the amount of training data was systematically reduced. Methods reached overall accuracies ranging from 85% to 95%, which demonstrates the ability of 250 m imagery to resolve fields down to 20 ha. Despite significantly different error rates, the site effect was found to persistently dominate the method effect. This was confirmed even after removing the share of the classification due to the spatial resolution of the satellite data (from 10% to 30%). This underlines the effect of other agrosystems characteristics such as cloudiness, crop diversity, and calendar on the ability to perform accurately. All methods have potential for large area cropland mapping as they provided accurate results with 20% of the calibration data, e.g. 2% of the study area in Ukraine. To better address the global cropland diversity, results advocate movement towards a set of cropland classification methods that could be applied regionally according to their respective performance in specific landscapes. 相似文献