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1.
We present a simple and effective method for constructing a gallery that consists of weathering effect elements called time-dependent appearance manifolds (TDAMs). Since TDAMs are computed from sample video clips showing dynamic weathering phenomena, they represent very smooth changes in the appearance of weathered pixels over time. Once a gallery with a variety of weathering effects is prepared, users can interactively choose and apply the predefined effects onto the surface of 3D graphic models and then finally assign the most appropriate one. This video-based weathering method can be implemented with very simple algorithms and it supports predictable, intuitive, and natural effects. Our system allows users to produce photorealistic augmented videos that include 3D graphic models weathered by our method. Moreover, users can easily enhance the realism of the augmented videos by manipulating rendering parameters such as the degree of weathering, texturing, lighting, and shadowing through user-friendly graphical user interfaces (GUIs).  相似文献   
2.
Navigation system for high-speed trains is necessary for increased operational safety and efficiency, new services for customers, and low maintenance cost. This paper proposes a high accuracy navigation system for high-speed trains based on a sensor fusion algorithm, with non-holonomic constraints, for multiple sensors, such as accelerometers, gyroscopes, tachometers, Doppler radar, differential GPS, and RFID, and a map matching algorithm. In the proposed system, we consider the federated Kalman filter for sensor fusion, where local filters utilize filter models developed for various sensor types. Especially, the local Kalman filter for RFID positioning, that is detected at irregular time intervals due to the varying train speed and RFID tag spacing, is developed to maintain high performance during GPS outage. In addition, an orthogonal projection map matching algorithm is developed to improve the performance of the proposed system. The performance of the proposed system is demonstrated with numerous simulations for a high-speed train in Korea. The simulation results are analyzed with respect to the existence of tunnel, RFID deployment spacing, RFID location uncertainty, and DGPS error.  相似文献   
3.
In this study, we present a design of an optimized fuzzy cascade controller based on Hierarchical Fair Competition-based Genetic Algorithms (HFCGA) for a rotary inverted pendulum system. In this system, one controls the movement of a pendulum through the adjustment of a rotating arm. The objective is to control the position of the rotating arm and to make the pendulum maintain the unstable equilibrium point at vertical position. To control the system, we design a fuzzy cascade controller scheme which consists of two fuzzy controllers arrange in a cascaded topology. The parameters of the controller are optimized by means of the HFCGA algorithm. The fuzzy cascade scheme comprises two controllers located in two loops. An inner loop controller governs the position of the rotating arm while an outer controller modifies a set point of the inner controller implied by the changes of the angle of pendulum. The HFCGA being a computationally effective scheme of the Parallel Genetic Algorithm (PGA) has been developed to eliminate an effect of premature convergence encountered in Serial Genetic Algorithms (SGA). It has emerged as an effective optimization vehicle to deal with very large search spaces. A comparative analysis involving computing simulations and practical experiment demonstrates that the proposed HFCGA based fuzzy cascade controller comes with superb performance in comparison with the conventional Linear Quadratic Regulator (LQR) controller as well as HFCGA-based PD cascade controller.  相似文献   
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Protection of Metals and Physical Chemistry of Surfaces - Cucumis anguria L. (C. anguria L.) commonly known as Indian gherkin is originally from Africa, though now seen widely in southeast,...  相似文献   
6.
In a distributed environment, a specific right may be required while a task is controlled and processed. A user should delegate enough rights to a task for processing. Tasks cannot work correctly if delegated rights are insufficient, or security threats may occur if delegated rights are excessive. Restricted delegation is the step that delegates proper rights to a task, and that enables fine-grained authorization in the Grid. In this paper, we propose the WAS architecture as a method for supporting restricted delegation and rights management. In contrast to traditional architecture, the WAS architecture uses a workflow that describes the sequence of rights required for normal execution of a task. By using the workflow, the WAS architecture is able to check whether the task exercises allowed rights. The WAS architecture is implemented on Globus toolkit 2.0 and extended on Globus toolkit 3.0.  相似文献   
7.
We present an interactive-speed algorithm for computing the Hausdorff Distance (HD) between two freeform geometric models represented with NURBS surfaces. The algorithm is based on an effective technique for matching a surface patch from one model to the corresponding nearby surface patch on the other model. To facilitate the matching procedure, we employ a bounding volume hierarchy (BVH) for freeform NURBS surfaces, which provides a hierarchy of Coons patches and bilinear surfaces approximating the NURBS surfaces (Kim et al., 2011 [1]). Comparing the local HD upper bound against a global HD lower bound, we can eliminate the majority of redundant surface patches from further consideration. The resulting algorithm and the associated data structures are considerably simpler than the previous BVH-based HD algorithms. As a result, we can compute the HD of two freeform geometric models efficiently and robustly even when the two models are in close proximity. We demonstrate the effectiveness of our approach using several experimental results.  相似文献   
8.
PbTiO3 and/or BaTiO3 were systematically introduced into Pb(Zn1/2W1/2)O3 and resultant phase developments in terms of perovskite formation were investigated. Ceramic powders were prepared via a B-site precursor route to further assist the perovskite formation. Weak-field dielectric properties of the sintered samples were examined. For Pb(Zn1/2W1/2)O3-rich compositions, multiphase ceramics resulted and formation of monophasic perovskite turned out to be not successful even by the B-site precursor method. Values of the perovskite formation yield and the maximum dielectric constant increased with increasing fractions of the substituent species.  相似文献   
9.
Among various Cu/ZnO/ZrO2 catalysts with the Cu/Zn ratio of 3/7, the one with 15 wt.% of ZrO2 obtains the best activity for methanol synthesis by hydrogenation of CO. The TPR, TPO and XPS analyses reveal that a new copper oxide phase is formed in the calcined Cu/ZnO/ZrO2 catalysts by the dissolution of zirconium ions in copper oxide. In addition, the Cu/ZnO/ZrO2 catalyst with 15 wt.% of ZrO2 turns out to contain the largest amount of the new copper oxide phase. When the Cu/ZnO/ZrO2 catalysts is reduced, the Cu2+ species present in the ZrO2 lattice is transformed to Cu+ species. This leads to the speculation that the addition of ZrO2 to Cu/ZnO catalysts gives rise to the formation of Cu+ species, which is related to the methanol synthesis activity of Cu/ZnO/ZrO2 catalyst in addition to Cu metal particles. Consequently, the ratio of Cu+/Cu0 is an important factor for the specific activity of Cu/ZnO/ZrO2 catalyst for methanol synthesis.  相似文献   
10.
The growth of Microcystis aeruginosa UTEX 2388 was repressed by ultrasonic radiation and resulted in an increased chlorophyll a content and cell size, suggesting the inhibition of cell division. However, growth was recovered immediately after the interruption of ultrasonication. In addition to the disruption of gas vesicles, other mechanisms of growth inhibition were also investigated. Although free radicals were produced by ultrasonication and hydrogen peroxide, the resulting lipid peroxidation in the cells was not comparable, indicating minimal damage by the free radicals. Ultrasonic radiation late in the day was found to be most effective in reducing the growth rate of M. aeruginosa, and this timing also corresponded to the phase of daily cell division. In an enclosure experiment, ultrasonic radiation reduced the pH, DO, total nitrogen, and total phosphorus, whereas it increased the water temperature, conductivity, and orthophosphate concentration. The algal cell density and chlorophyll a concentration drastically decreased after 3 d of ultrasonication, plus the cyanobacterial proportion was selectively reduced as compared to other algal species. Accordingly, ultrasonic radiation would appear to have considerable potential as an effective control method for cyanobacterial blooms.  相似文献   
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