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991.
Serge Guillaume Luis Magdalena 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2006,10(9):773-784
This paper proposes a method for building accurate and interpretable systems by integrating expert and induced knowledge into a single knowledge base. To favor the cooperation between expert knowledge and data, the induction process is run under severe constraints to ensure the fully control of the expert. The procedure is made up of two hierarchical steps. Firstly, a common fuzzy input space is designed according to both the data and expert knowledge. The compatibility of the two types of partitions, expert and induced, is checked according to three criteria : range, granularity and semantic interpretation. Secondly, expert rules and induced rules are generated according to the previous common fuzzy input space. Then, induced and expert rules have to be merged into a new rule base. Thanks to the common universe resulting from the first step, rule comparison can be made at the linguistic level only. The possible conflict situations are managed and the most important rule base features, consistency, redundancy and completeness, are studied. The first step is thoroughly described in this paper, while the second is only introduced. 相似文献
992.
Abstract
We consider elliptic partial differential equations with Neumann boundary conditions on complicated domains. The discretization
is performed by composite finite elements.
The a priori error analysis typically is based on precise knowledge of the regularity of the solution. However, the constants in the regularity estimates possibly
depend critically on the geometric details of the domain and the analysis of their quantitative influence is rather involved.
Here, we consider a polyhedral Lipschitz domain Ω with a possibly huge number of geometric details ranging from size O(ε) to O(1). We assume that Ω is a perturbation of a simpler Lipschitz domain Ω. We prove error estimates where only the regularity of the partial differential equation on Ω is needed along with bounds on the norm of extension operators which are explicit in appropriate geometric parameters.
Since composite finite elements allow a multiscale discretization of problems on complicated domains, the linear system which
arises can be solved by a simple multi-grid method. We show that this method converges at an optimal rate independent of the
geometric structure of the problem. 相似文献
993.
José M. Alonso Luis Magdalena Serge Guillaume Miguel A. Sotelo Luis M. Bergasa Manuel Ocaña Ramón Flores 《Journal of Intelligent and Robotic Systems》2007,48(4):539-566
The paper describes the application of fuzzy techniques to analyze motion problems in a mobile robot. The robot is equipped
with ultrasound sensors used for obstacle detection, but, in some cases, small obstacles are out of the range of the sensors
and can be dragged by the robot without being detected. Using other variables as, measured velocity, undershoots of that velocity
or changes in battery voltage, a fuzzy system is able to determine those situations. The paper also analyzes the knowledge
extraction process for the application using expert and induced knowledge (from data collected during navigation tasks) in
a cooperative way, dealing with integration and simplification issues. The expert knowledge was used for describing the robot
behaviour in order to identify the variables that should be used with the aim of detecting a collision of the vehicle against
an undetected obstacle, as well as proposing a suitable recovery action. Data collected in real trials were used for inducing
knowledge so as to complete and validate the expert knowledge. Both kind of knowledge were integrated in the final fuzzy-based
system. The aim is to build up a knowledge base, which is interpretable and accurate at the same time, and it is used by our
fuzzy system in order to solve the motion problems under consideration. 相似文献
994.
In order to design and analyse complex systems, modelers need formal models with two contradictory requirements: a high expressivity
and the decidability of behavioural property checking. Here we present and develop the theory of such a model, the recursive
Petri nets. First, we show that the mechanisms supported by recursive Petri nets enable to model patterns of discrete event
systems related to the dynamic structure of processes. Furthermore, we prove that these patterns cannot be modelled by ordinary
Petri nets. Then we study the decidability of some problems: reachability, finiteness and bisimulation. At last, we develop
the concept of linear invariants for this kind of nets and we design efficient computations specifically tailored to take
advantage of their structure. 相似文献
995.
The authors present the history of the founding of the French journal L'Année Psychologique. The names of T. Ribot (1839–1916), H. Beaunis (1830–1921), and A. Binet (1857–1911) are closely associated with the journal. Ribot's election to the chair of Experimental and Comparative Psychology at the Collège de France in 1888 marked the official emancipation of psychology in France. Because there was no laboratory associated with the chair, Beaunis, a physiological psychologist from Nancy, proposed to Ribot the creation of the first French laboratory of experimental psychology (1889). Under Beaunis's direction, this laboratory was established at the Sorbonne in Paris but was in fact dependent on another educational institution, L'Ecole Pratique des Hautes Etudes. In 1893 the laboratory's research was first published in a yearly journal named Travaux du Laboratoire de Psychologie Physiologique (2 volumes: 1893–1894). Binet, who joined the laboratory in 1891, was not satisfied by the form of this publication. With Beaunis's agreement, he then created L'Année Psychologique in 1894 to develop the reputation of the laboratory's research. The authors present the evolution and vicissitudes of the journal from 1895 to 1912, with a glance up to the present. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
996.
997.
Public hearings in environmental and social impact assessment for energy sector projects in Cameroon
Cyrille Valence Ngouana Kengne Serge Emeran Menang Evouna Dieudonné Bitondo 《影响评估与项目评价》2013,31(1):64-73
In Cameroon, like in other countries, public hearings are the most common method of citizen involvement mentioned in Environmental and Social Impact Assessment (ESIA). To elicit various attributes of current practice and characteristics of these public hearings in Cameroon, with focus on access, process and outcomes, we used an interpretive approach. This research unveiled an array of problems, including shortcomings in public hearing practice, law and regulatory framework, limited access to information, and inconvenient location of reading rooms (depositories). Public hearings do take place in depositories but they do not provide participants with the opportunity for direct debate and consensus-building. This research demonstrated that, local economic stakes tend to take precedence over critical questioning during public hearing events. However, public hearings in Cameroon attest to the growing willingness to challenge ESIA reports that may be fully backed by the government. In order for public hearings to be worthwhile events in Cameroon, there is need to build credibility and mutual trust among stakeholders. 相似文献
998.
999.
Wichard T Gerecht A Boersma M Poulet SA Wiltshire K Pohnert G 《Chembiochem : a European journal of chemical biology》2007,8(10):1146-1153
Lipid and fatty acid composition are considered to be key parameters that determine the nutritive quality of phytoplankton diets for zooplanktonic herbivores. The fitness, reproduction and physiology of the grazers are influenced by these factors. The trophic transfer of lipids and fatty acids from algal cells has been typically studied by using simple extraction and quantification approaches, which, as we argue here, do not reflect the actual situation in the plankton. We show that cell disruption, as it occurs during a predator's grazing on diatoms can drastically change the lipid and fatty acid content of the food. In some algae, a rapid depletion of polyunsaturated fatty acids (PUFAs) is observed within the first minutes after cell disruption. This fatty acid depletion is directly linked to the production of PUFA-derived polyunsaturated aldehydes (PUA); these are molecules that are thought to be involved in the chemical defence of the algae. PUA-releasing diatoms are even capable of transforming lipids from other sources if these are available in the vicinity of the wounded cells. Fluorescent staining reveals that the enzymes involved in lipid transformation are active in the foregut of copepods, and therefore link the depletion processes directly to food uptake. Incubation experiments with the calanoid copepod Temora longicornis showed that PUFA depletion in PUA-producing diatoms is correlated to reduced hatching success, and can be compensated for by externally added single fatty acids. 相似文献
1000.
Ethanol-mediated metal transfer printing (mTP) is a soft method, which allows to efficiently deposit metals onto various organic surfaces for applications in organic electronics. This simple approach in based on the stronger adhesion of the metals to the organic materials in the presence of thin ethanol layer between the metallized PDMS and the substrate due to the capillary action. Patterns with a resolution of at least 20 μm have been obtained on organic polymeric materials and photoresists without heating or applied pressure. Compared to other methods ethanol mediated mTP is considerably faster and has smaller limitations on the stamp depth. Residual silicone layer detected on the metal surface after the transfer by XPS studies has been mostly removed by UV/ozone treatment. Organic field-effect transistors (OTFTs) based on the metal electrodes deposited by mTP have been successfully fabricated and tested. 相似文献