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91.
Component-based development (CDB) promises to reduce complexity and cost of software development and maintenance through reuse. For CBD to be successful, a vibrant market for commercial business components is essential. One of the key requirements of an active market for business components is an effective scheme for classifying and describing them at various levels of detail, as well as a corresponding repository for storing and retrieving these components. Such a scheme needs to support various constituents such as business users, managers, and application assemblers. The scheme and repository should help users and managers to select components that match their requirements and aid application assemblers in identifying components most compatible with their deployment environment (such as the platform) and system inputs (such as data types). Drawing from the concepts of group technology and software reuse paradigm, this paper proposes a scheme for classifying and describing business components and the design of a knowledge-based repository for their storage and retrieval. The proposed scheme is implemented in a prototype repository. The effectiveness of the prototype and the underlying classification and coding scheme is assessed empirically through controlled experiments. Results support the assertion that the scheme is effective in enhancing the users' and analysts' ability to find the needed business components.  相似文献   
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93.
Phishing websites become a critical cybersecurity threat affecting individuals and organizations. Phishing-website detection tools are designed to protect users against such sites. Nevertheless, detection tools face serious user trust and suboptimal performance issues which require trust calibration to align trust with the tool’s capabilities. We employ the theoretical framework of automation trust and reliance as a kernel theory to develop the trust calibration model for phishing-website detection tools. We test the model using a controlled lab experiment. The results of our analysis show that users’ trust in detection tools can be calibrated by trust calibrators. Moreover, users’ calibrated trust has significant consequences, including users’ tool reliance, use, and performance against phishing websites.  相似文献   
94.
Anafcheh  Maryam  Zahedi  Mansour 《Catalysis Letters》2022,152(4):1224-1232
Catalysis Letters - The AlH2-catalyzed hydrogenation of carbon dioxide into formic acid by a novel catalyst of aluminum ligated NNN pincerfullerene, AlH2-bis(imino)pyrollidinofullerene, was...  相似文献   
95.
Due to the type of applications, wireless sensor nodes must always be inexpensive and small. Hence, the presence of constraints such as the limitation of energy resource is inevitable. So far, several studies have been carried out in order to present solutions for the reduction of energy consumption. In the meantime, clustering is given prime significance as an efficient method, which means partitioning network into distinct areas and is a way for managing nodes communication. In clustering algorithms, although the continuous execution of clustering phase and dynamic cluster head selection lead to energy consumption parity, they cause considerable energy dissipation due to the need for message transmitting to set new clusters and cluster heads. In this paper, the effect of using reservation to reduce message transmitting and energy dissipation has been studied. Reservation is the mechanism by the aid of which the number of communicated messages for the regular execution of clustering phase and cluster head selection can be reduced. The results of analysis and simulation show that the proposed method has significant impact on energy dissipation reduction.  相似文献   
96.
Off‐grade poly(ethylene terephthalate) (PET) of industrial manufacturers was partially depolymerized using excess ethylene glycol in the presence of manganese acetate as a transesterification catalyst to synthesize PET oligomers. Influences of reaction time, Ethylene Glycol (EG)/PET molar ratio, catalyst concentrations, and particle size of off‐grade PET on yield of partial glycolysis reaction were investigated based on Box–Behnken's design of experiment. Thermal analyses of glycolyzed products are examined by differential scanning calorimetry. The optimum samples were also well‐characterized by Fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy (1H‐NMR and 13C‐NMR). The optimal conditions to synthesize PET oligomer (melting point of about 180°C) for a 120‐min glycolysis reaction time were EG/PET molar ratio of 2 with no catalyst using granule‐shaped PET. The same results were obtained for a 60‐min glycolysis reaction time, including EG/PET molar ratio of 1 with the weight ratio (catalyst to PET) of 0.5% using average particle size of PET. Then, maleated PET as a compatibilizer for preparing PET nanocomposites was produced via reaction between maleic anhydride/phthalic anhydride composition and optimized PET oligomers based on central composite design of experiment. The combination of reaction time of 106 min and PhA/MA molar ratio of 0.85 gave the best results based on d‐spacing and peak shift of nanocomposite samples. Hence, melt mixing of maleated PET with organoclay produced a good intercalation of layered silicate and good dispersion of clay in maleated PET matrix. Analysis of variance (ANOVA) was studied for both glycolyzed products and functionalized PET oligomers. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers  相似文献   
97.
In this study, micro-machining of f.c.c. single-crystal materials was investigated based on a hybrid modelling approach combining smoothed particle hydrodynamics and continuum finite element analysis. The numerical modelling was implemented in the commercial software ABAQUS/Explicit by employing a user-defined subroutine VUMAT for a crystal plasticity formulation to gain insight into the underlying mechanisms that drive a plastic response of materials in high deformation processes. The numerical studies demonstrate that cutting force variations in different cutting directions are similar for different f.c.c. crystals even though the magnitudes of the cutting forces are different.  相似文献   
98.
Asphaltene is the heaviest fraction of oil, and if the thermodynamic conditions of oil change, it can be separated from oil precipitate. Of common methods for preventing asphaltene precipitation, using predictive methods, biological methods and injection of dispersants can be mentioned. In this study, the effect of two dispersants of toluene and dodecylbenzene sulfonic acid on asphaltene precipitation of a dead and a live oil sample has been investigated. According to the results, these dispersants in dead oil create an optimum point for asphaltene precipitation. In live oil, these dispersants reduce asphaltene precipitation down to 70%. In addition, it was observed that as an effect of injecting these dispersants, the average sizes of asphaltene flocculation have reduced.  相似文献   
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100.
This paper investigates steady-state and dynamic simulation of an industrial fixed-bed ethylene oxide reactor. A mathematical heterogeneous one-dimensional model is developed for simulation of reactor performance in the presence of long term deactivation of silver/a-alumina catalyst. In this paper, steady-state model of the reactor is solved and results of steady state simulation are fed to dynamic simulator as initial condition. When results of dynamic simulation are compared with industrial reactor data, it is found that there were good agreements between simulation results and industrial data. The proposed model is also validated by industrial process data for a period of 1100 operating days.  相似文献   
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