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91.
In this article, the authors developed several hypotheses regarding both the main and interactive effects of 2 types of team inputs on backing up behaviors in teams: (a) team composition characteristics in terms of the personality of the members of the team and (b) team task characteristics in terms of the extent to which the nature of the task is one that legitimately calls for some members of the team to back up other members of the team. Results from a study of 71 4-person teams performing a computerized tactical decision-making task suggest that the legitimacy of the need for back up has an important main effect on the extent to which team members provide assistance to and receive assistance from each other. In addition, the legitimacy of the need for back up also has important interactive effects with both the personality of the back up recipient and the personality of the back up providers on backing up behaviors in teams. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
92.
This article tests the degree to which personal and situational variables impact the acquisition of knowledge and skill within interactive project teams. On the basis of the literature regarding attentional capacity, constructive controversy, and truth-supported wins, the authors examined the effects of cognitive ability, workload distribution, Agreeableness, Openness to Experience, and structure on team learning. Results from 109 four-person project teams working on an interdependent command and control simulator indicated that teams learned more when composed of individuals who were high in cognitive ability and when the workload was distributed evenly. Conversely, team learning was negatively affected when teams were composed of individuals who were high in Agreeableness. Finally, teams using a paired structure learned more than teams structured either functionally or divisionally. Theoretical and practical implications are discussed, as well as possible limitations and directions for future research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
93.
Robots facilitate exploration of hazardous environments during response to catastrophe. Autonomous robotic platforms involved in search and rescue operations require accurate position and orientation (localization) information for self-navigation from its current position to its subsequent destination. A Hybrid Routing Algorithm Model has been proposed by the SPACE (structures, pointing and control engineering) URC (university research center) at California State University of Los Angeles. This model envisions three-layered terrain mapping with obstacle representations from various information sources such as satellites, UAVs and onboard range sensors. A* path-finding algorithm is applied to the outer two layers of the model (Layer 1 and Layer 2), while dynamic A* algorithm is responsible for innermost layer (Layer 3) navigation. The mobile robot localization information is computed using data obtained from a 9 Degrees of Freedom Inertial Measurement Unit. While gyroscope sensors provide the system the instantaneous radial velocity of a turning platform, these sensors are also susceptible to drift. Accelerometers are extremely sensitive to vibrations, and along with fluctuating magnetic fields, both accelerometers and magnetometers exhibit noisy behaviors when localizing the robot. Since the IMU contains all three sensors, a Kalman Filter is implemented on a PSoC-5 microcontroller to fuse data from the IMU sensors. This reduces standard deviation between measurements and improves reported heading accuracy, hence provides reliable information on the robot's localization and improves mapping.  相似文献   
94.
This work shows a fast and economic screening of packaging materials for food using a multisensor system. The multisensor system comprises a sampling system (in most cases a headspace sampler), a sensor array, and operation and evaluation electronics. The added value of the inclusion in the sampling system of a separation unit (e.g., chromatographic column) was proved for two different cases. The first is the elimination of a major interfering gas (e.g., water vapor); this was achieved with a short packed polar column that separated water vapor and organic solvents into two peaks. The second case is the extension of the correlation capability to human sensory panels. This was made possible by the use of a long capillary column that separates the high-concentration solvent components, which might not have a strong odorous effect, from the trace odorous ones. The latter are thus detected due to the high sensitivity of the sensor array.  相似文献   
95.
The purpose of this study was to utilize the job demands-resources model to examine the direct and interactive effects of job demands and cross-training on cognitive, behavioral, and affective outcomes in teams. Results from 54 teams indicated that an increase in job demands reduced mental model accuracy and information allocation and increased tension among team members. Cross-training, on the other hand, increased mental model accuracy and decreased tension among team members. More importantly, the direct effects of cross-training were qualified by the interaction. When job demands were high, cross-trained teams evidenced higher mental model accuracy, more information allocation, and less tension than teams that were not cross-trained. Cross-training was less influential when job demands were low, indicating that cross-training acted as a resource to buffer the negative impact of job demands in teams. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
96.
The tremendous success of the World Wide Web is countervailed by efforts needed to search and find relevant information. For tabular structures embedded in HTML documents, typical keyword or link-analysis based search fails. The Semantic Web relies on annotating resources such as documents by means of ontologies and aims to overcome the bottleneck of finding relevant information. Turning the current Web into a Semantic Web requires automatic approaches for annotation since manual approaches will not scale in general. Most efforts have been devoted to automatic generation of ontologies from text, but with quite limited success. However, tabular structures require additional efforts, mainly because understanding of table contents requires the comprehension of the logical structure of the table on the one hand, as well as its semantic interpretation on the other. The focus of this paper is on the automatic transformation and generation of semantic (F-Logic) frames from table-like structures. The presented work consists of a methodology, an accompanying implementation (called TARTAR) and a thorough evaluation. It is based on a grounded cognitive table model which is stepwise instantiated by the methodology. A typical application scenario is the automatic population of ontologies to enable query answering over arbitrary tables (e.g. HTML tables).  相似文献   
97.
Microstructure Development in Low-Antimony Oxide-Doped Zinc Oxide Ceramics   总被引:1,自引:0,他引:1  
The grain growth of ZnO ceramics sintered with low additions of Sb2O3 (<500 ppm of Sb) was investigated. Additions of Sb<250 ppm resulted in a coarse-grained microstructure with large ZnO grains (55–70 μm), much larger than the grain size of ZnO ceramics without any Sb2O3 addition (45 μm). The addition of 500 ppm of Sb resulted in a fine-grained microstructure with an average ZnO grain size of about 12 μm. The results are explained by an inversion-boundary (IB) -induced grain-growth mechanism. The grain-growth exponent has a value of about 2 as long as the grains containing IBs grow at the expense of IB-free grains. It increases to about 4 after the IB-containing grains impinge on each other, and achieves values above 10 for additions of 500 ppm of Sb when IBs nucleate in nearly all the ZnO grains so that grains with IBs prevail in the microstructure at an early stage in the grain-growth process.  相似文献   
98.
Simultaneous work function change and conduction measurements have been performed on undoped SnO2 thick film sensors in order to investigate the surface reactions of CO under dry and humid conditions. On their basis, changes in the electron affinity have been observed for the reaction with water and the reaction with CO in the background of water. Additionally, by comparing the results for the changes in band bending, one can conclude that both water and CO compete for the same reaction sites, i.e. preadsorbed oxygen species. The kinetics of work function and band bending changes show that in the case of humid air more than one dipole species is involved in the reaction with CO.  相似文献   
99.
This paper describes a novel mobile virtual-distrubuted system architecture for supporting global mobile computing and communications. the principal contribution of this paper is to innovatively apply virtual memory concepts to mobile systems by deploying mobile-floating agents to de-couple services and resources from the underlying network and allow them to move around following their mobile users. The mobile-floating agents maintain data structures associated with a mobile user. By combining the mobile-floating agent functions with a predictive mobility management algorithm and location-aware caching and prefetching, services and user data structure are pre-connected and pre-assigned at the locations to which the user is moving. Thus, the users can maintain their data structures or immediately receive service with virtually the same efficiency as at the previous location.  相似文献   
100.
Human hematopoietic niches are complex specialized microenvironments that maintain and regulate hematopoietic stem and progenitor cells (HSPC). Thus far, most of the studies performed investigating alterations of HSPC‐niche dynamic interactions are conducted in animal models. Herein, organ microengineering with microfluidics is combined to develop a human bone marrow (BM)‐on‐a‐chip with an integrated recirculating perfusion system that consolidates a variety of important parameters such as 3D architecture, cell–cell/cell–matrix interactions, and circulation, allowing a better mimicry of in vivo conditions. The complex BM environment is deconvoluted to 4 major distinct, but integrated, tissue‐engineered 3D niche constructs housed within a single, closed, recirculating microfluidic device system, and equipped with cell tracking technology. It is shown that this technology successfully enables the identification and quantification of preferential interactions—homing and retention—of circulating normal and malignant HSPC with distinct niches.  相似文献   
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