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31.
The relation between a speaker's personality and his/her propensity to interrupt was examined in 30-min unstructured conversations for 36 dyads of undergraduates (12 male, 12 female, and 12 mixed sex). Two predictions were tested: (a) interruptive behavior is inversely related to speech anxiety and positively related to confidence as a speaker, and (b) interruptive behavior is inversely related to social anxiety (avoidance–distress; fear of negative evaluation). A stepwise multiple regression analysis was performed, controlling for the systematic effects of sex, the conversational partner's personality and amount of speech, and the speaker's use of back-channel responses. These hypotheses were confirmed for rate of total interruptions and rate of successful interruptions, for percentage of successful interruptions, and for mean duration of interruptions; the results withstood cross-validation analysis. (37 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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We report the first detection of the pure rotational spectra of H79 Br and H81 Br in the first excited vibrational state at room temperature. We recorded the spectra with a tunable far-infrared spectrometer equipped with an optimized Ge:Ga photodetector and an improved multiple-pass gas cell to enhance the overall sensitivity. In particular, a minimum detectable absorption of better than 10-7 cm-1 was achieved. We measured a total of 60 frequencies for the two isotopomers with an accuracy of a few parts in 108 . The hyperfine structure was observed at the lower J values. The derived spectroscopic parameters, which include nuclear and quadrupole hyperfine constants, reproduce the assigned transitions within their experimental errors.  相似文献   
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Peng  Chao  Zeng  Haibo  Natale  Marco Di 《Real-Time Systems》2019,55(3):598-638
Real-Time Systems - Synchronous reactive models are widely used in the development of embedded software and systems. The schedulability analysis of tasks obtained as the code implementation of...  相似文献   
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This paper presents the MDE process in use at Elettronica SpA (ELT) for the development of complex embedded systems integrating software and firmware. The process is based on the adoption of SysML as the system-level modeling language and the use of Simulink for the refinement of selected subsystems. Implementations are generated automatically for both the software (C++ code) and firmware parts, and communication adapters are automatically generated from SysML using a dedicated profile and open-source tools for modeling and code generation. The process starts from a SysML system model, developed according to the platform-based design paradigm, in which a functional model of the system is paired to a model of the execution platform. Subsystems are refined as Simulink models or hand-coded in C++. An implementation for Simulink models is generated as software code or firmware on FPGA. Based on the SysML system architecture specification, our framework drives the generation of Simulink models with consistent interfaces, allows the automatic generation of the communication code among all subsystems (including the HW–FW interface code). In addition, it provides for the automatic generation of connectors for system-level simulation and of test harnesses and mockups to ease the integration and verification stage. We provide early results on the time savings obtained by using these technologies in the development process.  相似文献   
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This paper focusses on a study carried out in order to increase productivity in gas metal arc welding (GMAW) processes by optimising the deposition rate of the filler metal. To reach this aim, a possible solution was found in developing an adaptive system that is able to control and keep the wire feed speed constant at a desired and optimal value. This control has been accomplished by regulating an opportune variable typical of the welding process; in this case, the attention was focussed on the welding current intensity. Typical difficulties of GMAW processes, due above all to the great number of main variables and to their interdependence, suggested the possible solution by modelling a fuzzy-logic-based system, whose elements were determined by training an artificial neural network (ANN) with experimental data, obtained from bead on plate welds. At the same time, mathematical models, based on multiple regression analysis, were developed from the same data, in order to provide a comparison term and to assess the effectiveness of the neuro-fuzzy approach versus the mathematical methods. The results of this study confirmed the effectiveness of the proposed approach in the development of an integrated welding system in order to increase productivity.  相似文献   
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In this paper the performances of an electronic nose based on metalloporphyrin‐coated quartz microbalance sensors and of an experienced panel of seven human assessors in the evaluation of gases derived from degradation reactions in tomatoes are presented and discussed. The performances are measured in terms of the capability of both systems to distinguish between samples of different quality coming from conventional and organic production systems. The study deals with the application of pattern recognition techniques based on either multivariate statistical methods (PCA, GPA) or artificial neural networks using a self‐organising map (SOM). The response pattern of the sensor array and the sensory data are analysed and compared using these methods. Similarities in the classification of the data by electronic nose and human sensory profiling are found. © 2000 Society of Chemical Industry  相似文献   
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The objective of obtaining high performance energy buildings can be reached considering the contemporaneous effects of technical characteristics and occupancy. Recent studies report that as buildings become more energy efficient, the behavior of occupants plays an increasing role in consumption. Therefore, a construction designed to be a Nearly Zero Energy Building (nZEB) might generate higher consumption than expected if the assumptions made in the simulation process are not respected during the real use. The occupant can modify the control strategies of internal variables (heating/cooling system operation, set point temperature, ventilation, lighting) and the users’ behavior has a high impact on the utilization of plants and equipment. A significant contribution is also represented by the internal gains that have a direct relation with occupancy. The aim of this study is to assess the influence of housing occupancy patterns on the definition of residential nZEB in Italian climatic conditions. The investigation has been carried out considering a case study consisting of a building designed according to the National Standards. Successively, different conditions of the building usage are analyzed using dynamic energy simulations that allow exploration of the different occupation modes. The variability of the family composition and the occupancy scenarios are defined based on the data collected in the specific context. The investigation provides information regarding the effects of human variables (occupants’ needs and preferences) on the final energy performance of low energy buildings and highlights the combination of variables that are important in the definition of nZEB as net zero source energy.  相似文献   
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Since the price of Arabica is currently more than twice higher than Robusta, a rapid and reliable method for the determination of the roasted coffee blend composition is fundamental for the authentication of commercial blends used for the Italian Espresso coffee. A GC-FID method based on the ratio between the integrated peak areas of kahweol (K) divided by the sum of K and 16-O-methylcafestol (16MCF) was developed. No internal/external standard was used. Moreover, the quantitation of the unsaponifiable compounds is not necessary, as well as the calculation of any response factors. The percentage of Robusta in 34 samples of coffee blends with known composition, and in 48 samples of pure varieties was used to build a cubic polynomial function with R(2)=0.998. The roasting conditions did not affect the results. Considering eight commercial blends (ranging 0-90% Robusta), no significant difference (two-tailed P=0.817) was registered between the claimed and the predicted composition.  相似文献   
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