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21.
Enterprise architecture models can be used in order to increase the general understanding of enterprise systems and specifically
to perform various kinds of analysis. The present paper proposes a metamodel for enterprise systems modifiability analysis,
i.e. assessing the cost of making changes to enterprise-wide systems. The enterprise architecture metamodel is formalized
using probabilistic relational models, which enables the combination of regular entity-relationship modeling aspects with
means to perform enterprise architecture analysis. The content of the presented metamodel is validated based on survey and
workshop data and its estimation capability is tested with data from 21 software change projects. To illustrate the applicability
of the metamodel an instantiated architectural model based on a software change project conducted at a large Nordic transportation
company is detailed. 相似文献
22.
Primates are very good at recognizing objects independent of viewing angle or retinal position, and they outperform existing computer vision systems by far. But invariant object recognition is only one prerequisite for successful interaction with the environment. An animal also needs to assess an object's position and relative rotational angle. We propose here a model that is able to extract object identity, position, and rotation angles. We demonstrate the model behavior on complex three-dimensional objects under translation and rotation in depth on a homogeneous background. A similar model has previously been shown to extract hippocampal spatial codes from quasi-natural videos. The framework for mathematical analysis of this earlier application carries over to the scenario of invariant object recognition. Thus, the simulation results can be explained analytically even for the complex high-dimensional data we employed. 相似文献
23.
Rojas-Labanda Susana Sigmund Ole Stolpe Mathias 《Structural and Multidisciplinary Optimization》2017,56(6):1603-1612
Structural and Multidisciplinary Optimization - Structural topology optimization problems are commonly defined using continuous design variables combined with material interpolation schemes. One of... 相似文献
24.
Mathias M. Adankon Author Vitae Mohamed Cheriet Author Vitae 《Pattern recognition》2011,44(9):2220-2230
In this paper, we propose to reinforce the Self-Training strategy in semi-supervised mode by using a generative classifier that may help to train the main discriminative classifier to label the unlabeled data. We call this semi-supervised strategy Help-Training and apply it to training kernel machine classifiers as support vector machines (SVMs) and as least squares support vector machines. In addition, we propose a model selection strategy for semi-supervised training. Experimental results on both artificial and real problems demonstrate that Help-Training outperforms significantly the standard Self-Training. Moreover, compared to other semi-supervised methods developed for SVMs, our Help-Training strategy often gives the lowest error rate. 相似文献
25.
Steven Hancock Mathias Disney Jan-Peter Muller Philip Lewis Mike Foster 《Remote sensing of environment》2011,115(12):3286-3297
Lidars have the unique ability to make direct, physical measurements of forest height and vertical structure in much denser canopies than is possible with passive optical or short wavelength radars. However the literature reports a consistent underestimate of tree height when using physically based methods, necessitating empirical corrections. This bias is a result of overestimating the range to the canopy top due to background noise and failing to correctly identify the ground.This paper introduces a method, referred to as “noise tracking”, to avoid biases when determining the range to the canopy top. Simulated waveforms, created with Monte-Carlo ray tracing over geometrically explicit forest models, are used to test noise tracking against simple thresholding over a range of forest and system characteristics. It was found that noise tracking almost completely removed the bias in all situations except for very high noise levels and very low (< 10%) canopy covers. In all cases noise tracking gave lower errors than simple thresholding and had a lower sensitivity to the initial noise threshold.Finite laser pulses spread out the measured signal, potentially overriding the benefit of noise tracking. In the past laser pulse length has been corrected by adding half that length to the signal start range. This investigation suggests that this is not always appropriate for simple thresholding and that the results for noise tracking were more directly related to pulse length than for simple thresholding. That this effect has not been commented on before may be due to the possible confounding impacts of instrument and survey characteristics inherent in field data. This method should help improve the accuracy of waveform lidar measurements of forests, whether using airborne or spaceborne instruments. 相似文献
26.
This contribution provides an introduction to the Common Information Model CIM which is an international standard maintained by the International Electrotechnical Commission IEC. Today’s market requirements towards the model are discussed, furthermore, we give an introduction to the history of the CIM, its serializations and scope of application. The contribution concludes with an overview of future use of the CIM for both science and commerce. Briefly, we focus on: Message-based loose coupling of information systems Exchange of power grid topologies with minimal communication and data overhead Data quality assurance using ontology-based meta annotations and Integration of heterogeneous standards in the utility domain. The contribution presents solutions to the use cases providing a better information management for the utility utilizing the Common Information Model. 相似文献
27.
Sergey Smirnov Hajo A. Reijers Mathias Weske Thijs Nugteren 《Distributed and Parallel Databases》2012,30(1):63-99
The discipline of business process management aims at capturing, understanding, and improving work in organizations by using
process models as central artifacts. Since business-oriented tasks require different information from such models to be highlighted,
a range of abstraction techniques has been developed over the past years to manipulate overly detailed models. At this point,
a clear understanding of what distinguishes these techniques and how they address real world use cases has not yet been established.
In this paper we systematically develop, classify, and consolidate the use cases for business process model abstraction and
present a case study to illustrate the value of this technique. The catalog of use cases that we present is based on a thorough
evaluation of the state of the art, as well as on our cooperation with end users in the health insurance sector. It has been
subsequently validated by experts from the consultancy and tool vendor domains. Based on our findings, we evaluate how the
existing business process model abstraction approaches support the discovered use cases and reveal which areas are not adequately
covered, as such providing an agenda for further research in this area. 相似文献
28.
Organizations actively managing their business processes face a rapid growth of the number of process models that they maintain. Business process model abstraction has proven to be an effective means to generate readable, high-level views on business process models by showing coarse-grained activities and leaving out irrelevant details. In this way, abstraction facilitates a more efficient management of process models, as a single model can provide for many relevant views. Yet, it is an open question how to perform abstraction in the same skillful way as experienced modelers combine activities into more abstract tasks. This paper presents an approach that uses semantic information of a process model to decide on which activities belong together, which extends beyond existing approaches that merely exploit model structural characteristics. The contribution of this paper is twofold: we propose a novel activity aggregation method and suggest how to discover the activity aggregation habits of human modelers. In an experimental validation, we use an industrial process model repository to compare the developed activity aggregation method with actual modeling decisions, and observe a strong correlation between the two. The presented work is expected to contribute to the development of modeling support for the effective process model abstraction. 相似文献
29.
Deferred Splatting 总被引:2,自引:0,他引:2
30.
The quadrupole resonator, designed to measure the surface resistance of superconducting samples at 400 MHz has been refurbished. The accuracy of its RF-dc compensation measurement technique is tested by an independent method. It is shown that the device enables also measurements at 800 and 1200 MHz and is capable to probe the critical RF magnetic field. The electric and magnetic field configuration of the quadrupole resonator are dependent on the excited mode. It is shown how this can be used to distinguish between electric and magnetic losses. 相似文献