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931.
Nawel Takouachet Nadine Couture Patrick Reuter Pierre Joyot Guillaume Rivière Nicolas Verdon 《The Visual computer》2012,28(6-8):799-808
We present design principles for conceiving tangible user interfaces for the interactive physically-based deformation of 3D models. Based on these design principles, we developed a first prototype using a passive tangible user interface that embodies the 3D model. By associating an arbitrary reference material with the user interface, we convert the displacements of the user interface into forces required by physically-based deformation models. These forces are then applied to the 3D model made out of any material via a physical deformation model. In this way, we compensate for the absence of direct haptic feedback, which allows us to use a force-driven physically-based deformation model. A user study on simple deformations of various metal beams shows that our prototype is usable for deformation with the user interface embodying the virtual beam. Our first results validate our design principles, plus they have a high educational value for mechanical engineering lectures. 相似文献
932.
Guillaume Olive 《Mathematics of Control, Signals, and Systems (MCSS)》2012,23(4):257-280
In this work, we study the null-controllability properties of linear parabolic systems with constant coefficients in the case
where several controls are acting on different distributed subdomains and/or on the boundary. We prove a Kalman rank condition
in the one-dimensional case. In the case where only distributed controls are considered, we also establish related results
such as a Carleman estimate. 相似文献
933.
Within the framework of an air quality study of the French alpine valleys (POVA program), an atmospheric emission inventory concerning major pollutants: CO, NOx, SO(2), CH(4), particles (PT) and non-methane volatile organic compounds (NMVOC) was carried out. This inventory has a spatial resolution of 1 km(2) and was established for the reference year 2003. The coexistence of economic activities and the Vanoise national park makes the Maurienne valley a sensitive site, particularly representative of the problems of sustainable development in alpine areas, where air pollution is one of the most important aspects. The area, which covers 4588 km(2), is an alpine valley that is sensitive to air pollution due to the emission sources (traffic, industries, private heating, etc.), its morphology (a narrow valley surrounded by high ranges), and local meteorology (temperature inversions and slope winds). As expected, the result which includes both biogenic and anthropogenic sources shows serious emissions of pollutants that are mainly due to the presence of highways and industries around. Two emission inventories were drawn up: one with emission factors determined by CORINAIR (from the European Environment Agency) and the other with emission factors determined by BUWAL-OFEFP (from Swiss Agency for the Environment, Forests and Landscape). The inventories were then compared thanks to concentrations calculated from a numerical model. Computations were run for an intensive field observation period from 25 June to 2 July 2003. 相似文献
934.
Manuel Olbrich Holger Graf Svenja Kahn Timo Engelke Jens Keil Patrick Riess Sabine Webel Ulrich Bockholt Guillaume Picinbono 《The Visual computer》2013,29(10):1093-1105
The rapid development of geo-referenced information changed the way on how we access and interlink data. Smartphones as enabling devices for information access are main driving factor. Thus, the hash key to information is the actual position registered via camera and sensory of the mobile device. A rising technology in this context is Augmented Reality (AR) as its fuses the real world captured with the smartphone camera with geo-referenced data. The technological building blocks analyse the intrinsic sensor data (camera, GPS, inertial) to derive a detailed pose of the smartphone aiming to align geo-referenced information to our real environment. In particular, this is interesting to applications where 3D models are used in planning and organization processes as, e.g., facility management. Here, Building Information Models (BIM) were established in order to hold “as built” information, but also to manage the vast amount of additional information coming with the design, such as building components, properties, maintenance logs, documentation, etc. One challenge is to enable stakeholders involved in the overall building lifecycle to get mobile access to the management system within on-site inspections and to automatise feedback of newly generated information into the BIM. This paper describes a new AR framework that offers on-site access to BIM information and user centric annotation mechanism. 相似文献
935.
Three‐Dimensional Constrained Tracking Control Via Exact Differentiation Estimator of a Quadrotor Helicopter
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In this paper, a constructive method is presented to design a three dimensional trajectory tracking controller that forces a quadrotor helicopter to track a bounded and sufficiently smooth reference trajectory asymptotically in the presence of constant force disturbances. The quadrotor helicopter under consideration has fewer independent thrusters than degrees of freedom to be controlled. Motivated by the vehicle's steering practices, the roll and pitch angles are regarded as virtual controls along with four control forces to fulfill the task of position and yaw angle reference tracking. To prevent position constraint violation, the barrier Lyapunov function (BLF) is employed in the vectorial backstepping procedure to guarantee that the position and attitude constraints are not violated. The backstepping procedure employs an exact and robust sliding mode differentiator of order two to facilitate the implementation of the attitude command signal without calculating the virtual control signal derivative analytically. 相似文献
936.
Eduardo Steed Espinoza Octavio Garcia Guillaume Sanahuja Alejandro Malo Rogelio Lozano 《Journal of Intelligent and Robotic Systems》2013,70(1-4):151-163
This paper presents the development of a micro coaxial helicopter (MCR UAV) whose main characteristic is that it should be carried by an air shuttle transporter and then released in a desired place far away from the launching site, to develop surveillance missions in hover flight. A real-time embedded system is built in order to validate the proposed aerodynamic prototype, and a classic control law based on a classical backstepping procedure for the dynamic system is implemented to test this vehicle in autonomous flight. Finally, simulation and practical results are presented for hover flight. 相似文献
937.
2D visual servoing consists in using data provided by a vision sensor for controlling the motions of a dynamic system. Most of visual servoing approaches has relied on the geometric features that have to be tracked and matched in the image acquired by the camera. Recent works have highlighted the interest of taking into account the photometric information of the entire image. This approach was tackled with images of perspective cameras. We propose, in this paper, to extend this technique to central cameras. This generalization allows to apply this kind of method to catadioptric cameras and wide field of view cameras. Several experiments have been successfully done with a fisheye camera in order to control a 6 degrees of freedom robot and with a catadioptric camera for a mobile robot navigation task. 相似文献
938.
Dehestru G Leman M Jundt J Dryden P Sullivan M Harrison C 《The Review of scientific instruments》2011,82(3):035113
This article discusses a microfluidic vibrating wire viscometer with an internal volume of a few microliters. Accuracy of order ±10% for viscosities ranging from 0.1 to 100 cP is demonstrated for temperatures (10 °C-175 °C) and pressures (10-24,000 psi) suitable for oilfield use by prior calibration in air and toluene. Comparison between multiple data sets indicates that a large fraction of the discrepancy between literature values is systematic, indicating that future refinements may be possible with better interpretation. Confinement effects are evaluated and are not found to play a significant role, which is surprising since the ratio (6.6) of the fluid channel width to the wire diameter is very low. 相似文献
939.
Guillaume Demarcq Laurent Mascarilla Michel Berthier Pierre Courtellemont 《Journal of Mathematical Imaging and Vision》2011,40(3):269-284
The aim of this paper is to define an extension of the analytic signal for a color image. We generalize the construction of
the so-called monogenic signal to mappings with values in the vectorial part of the Clifford algebra ℝ5,0. Solving a Dirac equation in this context leads to a multiscale signal (relatively to the Poisson scale-space) which contains
both structure and color information. The color monogenic signal can be used in a wide range of applications. Two examples
are detailed: the first one concerns a multiscale geometric segmentation with respect to a given color; the second one is
devoted to the extraction of the optical flow from moving objects of a given color. 相似文献
940.