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51.
Over the years we have developed the Disciple theory, methodology, and family of tools for building knowledge-based agents. This approach consists of developing an agent shell that can be taught directly by a subject matter expert in a way that resembles how the expert would teach a human apprentice when solving problems in cooperation. This paper presents the most recent version of the Disciple approach and its implementation in the Disciple–RKF (rapid knowledge formation) system. Disciple–RKF is based on mixed-initiative problem solving , where the expert solves the more creative parts of the problem and the agent solves the more routine ones, integrated teaching and learning , where the agent helps the expert to teach it, by asking relevant questions, and the expert helps the agent to learn, by providing examples, hints, and explanations, and multistrategy learning , where the agent integrates multiple learning strategies, such as learning from examples, learning from explanations, and learning by analogy, to learn from the expert how to solve problems. Disciple–RKF has been applied to build learning and reasoning agents for military center of gravity analysis, which are used in several courses at the US Army War College.  相似文献   
52.
This paper presents our method, which simultaneously combines automatic imaging, identification, and counting with the acquisition of morphological information for at least 1000 blood cells from several three-dimensional images of the same sample. We started with seeking parameters to differentiate between red blood cells that are similar but different with respect to their development stage, i.e., mature or immature. We highlight that these cells have different diffractive patterns with complementary central intensity distribution in a given plane along the propagation axis. We use the Fresnel approximation to simulate propagation through cells modeled as spheroid-shaped phase objects and to find the cell property that has the dominant influence on this behavior. Starting with images obtained in the reconstruction step of the digital holographic microscopy technique, we developed a code for automated simultaneous individual cell image separation, identification, and counting, even when the cells are partially overlapped on a slide, and accurate measuring of their morphological features. To find the centroids of each cell, we propose a method based on analytical functions applied at threshold intervals. Our procedure separates the mature from the immature red blood cells and from the white blood cells through a decision based on gradient and radius values.  相似文献   
53.
The temporomandibular joint (TMJ) is a specialized synovial joint that is crucial for the movement and function of the jaw. TMJ osteoarthritis (TMJ OA) is the result of disc dislocation, trauma, functional overburden, and developmental anomalies. TMJ OA affects all joint structures, including the articular cartilage, synovium, subchondral bone, capsule, ligaments, periarticular muscles, and sensory nerves that innervate the tissues. The present review aimed to illustrate the main pathomechanisms involving cartilage and bone changes in TMJ OA and some therapeutic options that have shown potential restorative properties regarding these joint structures in vivo. Chondrocyte loss, extracellular matrix (ECM) degradation, and subchondral bone remodeling are important factors in TMJ OA. The subchondral bone actively participates in TMJ OA through an abnormal bone remodeling initially characterized by a loss of bone mass, followed by reparative mechanisms that lead to stiffness and thickening of the condylar osteochondral interface. In recent years, such therapies as intraarticular platelet-rich plasma (PRP), hyaluronic acid (HA), and mesenchymal stem cell-based treatment (MSCs) have shown promising results with respect to the regeneration of joint structures or the protection against further damage in TMJ OA. Nevertheless, PRP and MSCs are more frequently associated with cartilage and/or bone repair than HA. According to recent findings, the latter could enhance the restorative potential of other therapies (PRP, MSCs) when used in combination, rather than repair TMJ structures by itself. TMJ OA is a complex disease in which degenerative changes in the cartilage and bone develop through intricate mechanisms. The regenerative potential of such therapies as PRP, MSCs, and HA regarding the cartilage and subchondral bone (alone or in various combinations) in TMJ OA remains a matter of further research, with studies sometimes obtaining discrepant results.  相似文献   
54.
This paper presents the design of a new reduced order observer to estimate the state for a class of linear time-invariant multivariable systems with unknown inputs. The proposed design approach is a combination of the approaches proposed by Hou and Muller (IEEE Trans. Autom. Control 37:871–875, 1992) and Boubaker (Int. J. Autom. Control Syst. Eng. 5:45–51, 2005); matrix decompositions, state transformations, and substitutions based on coordinate changes are used. It is shown that the problem of reduced order observers for linear systems with unknown inputs can be reduced to a standard one (the unknown input vector will not interfere in the observer equations). The effectiveness of the suggested design algorithm is illustrated by a numerical example (aircraft lateral motion), and, for the same aircraft dynamics, we compare our new observer with other already existing observers from the existence conditions and dynamic characteristics point of view; the superiority of the new designed observer is demonstrated.  相似文献   
55.
In Romania, surface waters near underground salt mines represent a significant risk to the stability of the mine workings. Such problems occur in many salt exploiting facilities, i.e. Slanic Prahova, Targu Ocna, Praid. In this paper, the authors present a method of dealing with this issue at the Praid salt mine with research targeted at avoiding the hazard presented by intrusion of surface waters into old mine workings. Monitoring activities are proposed to prevent damage due to the seepage of Corund Creek water into the subsurface salt body, which could compromise and even produce collapses in the salt mine sanatorium and old and new mines.  相似文献   
56.
The transient thermoreflectance method has been used to measure the thermal conductivity of natural silicon and isotopically-pure silicon-28 layers that are epitaxially grown on natural silicon substrates. The measurements were performed at room temperature for both a low level (1016) and a higher level (2×1019) of Boron doping of the epitaxial layers. The results indicate a gain of approximately 55% in the thermal conductivity of Si28 as compared to that of natural Si, at both low and higher levels of doping, and a loss of approximately 19% for both types of silicon due to the higher level of doping.  相似文献   
57.
When Diana, Princess of Wales, was killed in 1997, a massive public outpouring of grief occurred. Six years after her death, the public and the tabloids still debate whether the paparazzi were to blame for her fatal car accident. Previous studies of celebrities suggest that psychological involvement with a celebrity will determine to what extent stories of the celebrity and their subsequent social influence will affect the general public. The same process was examined in this study of Princess Diana. To study this phenomenon, a survey administered immediately after her fatal car accident compared people's level of involvement with Princess Diana to their viewing of stories about her funeral and their attitudes toward the press. Results showed that gender and age similarities predicted involvement with Princess Diana. This involvement, in turn, predicted people's media use in response to her death and their attitudes toward the press. This finding reinforces previous studies that have shown involvement is an important variable that influences both media consumption and media effects. The authors consider implications of this research for investigating the growing international influence of celebrities through mass media.  相似文献   
58.
The temperature-programmed polycondensation of tetrachlorobisphenol A with chloromethylphosphonic dichloride is carried out in the sample tube of an NMR spectrometer. From the spectra during polycondensation, the instantaneous concentration of components can be determined. Phosphorus and chlorine-containing polymers with flame-retardant properties are obtained.  相似文献   
59.
The transfer of benchtop knowledge into large scale industrial production processes represents a challenge in the field of organic electronics. Large scale industrial production of organic electronics is envisioned as roll to roll (R2R) processing which nowadays comprises usually solution-based large area printing steps. The search for a fast and reliable fabrication process able to accommodate the deposition of both insulator and semiconductor layers in a single step is still under way. Here we report on the fabrication of organic field effect transistors comprising only evaporable small molecules. Moreover, both the gate dielectric (melamine) and the semiconductor (C60) are deposited in successive steps without breaking the vacuum in the evaporation chamber. The material characteristics of evaporated melamine thin films as well as their dielectric properties are investigated, suggesting the applicability of vacuum processed melamine for gate dielectric layer in OFETs. The transistor fabrication and its transfer and output characteristics are presented along with observations that lead to the fabrication of stable and virtually hysteresis-free transistors. The extremely low price of precursor materials and the ease of fabrication recommend the evaporation processes as alternative methods for a large scale, R2R production of organic field effect transistors.  相似文献   
60.
Science China Information Sciences -  相似文献   
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