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31.
User Activities Outliers Detection; Integration of Statistical and Computational Intelligence Techniques 下载免费PDF全文
In this article, a hybrid technique for user activities outliers detection is introduced. The hybrid technique consists of a two‐stage integration of principal component analysis and fuzzy rule‐based systems. In the first stage, the Hamming distance is used to measure the differences between different activities. Principal component analysis is then applied to the distance measures to find two indices of Hotelling's T2 and squared prediction error. In the second stage of the process, the calculated indices are provided as inputs to the fuzzy rule‐based systems to model them heuristically. The model is used to identify the outliers and classify them. The proposed system is tested in real home environments, equipped with appropriate sensory devices, to identify outliers in the activities of daily living of the user. Three case studies are reported to demonstrate the effectiveness of the proposed system. The proposed system successfully identifies the outliers in activities distinguishing between the normal and abnormal behavioral patterns. 相似文献
32.
Lounis Kessal Nicolas Abel Si Mahmoud Karabernou Didier Demigny 《Journal of Real-Time Image Processing》2008,3(3):131-147
Technology evolution makes possible the integration of heterogeneous components as programmable elements (processors), hardware
dedicated blocks, hierarchical memories and buses. Furthermore, an optimized reconfigurable logic core embedded within a System-on-Chip
will associate the performances of dedicated architecture and the flexibility of programmable ones. In order to increase performances,
some of the applications are carried out in hardware, using dynamically reconfigurable logic, rather than software, using
programmable elements. This approach offers a suitable hardware support to design malleable systems able to adapt themselves
to a specific application. This article makes a synthesis of the Ardoise project. The first objective of Ardoise project was
to design and to produce a dynamically reconfigurable platform based on commercial FPGAs. The concept of dynamically reconfigurable
architecture depends partially on new design methodologies elaboration as well as on the programming environment. The platform
architecture was designed to be suitable for real-time image processing. The article outlines mainly the Ardoise tools aspect:
development environment and real-time management of the hardware tasks. The proposed methodology is based on a dynamic management
of tasks according to an application scenario written using C++ language.
相似文献
Lounis KessalEmail: |
33.
34.
Global decentralized discrete sliding mode control of a class of interconnected system using only output information is considered in this paper. Matched and unmatched uncertainties as well as known and unknown interconnections are treated. Bounded time-varying delays are considered within the subsystems and through interconnections. The stability of the reduced-order interconnected systems is analyzed using the Lyapunov–Kraszovskii approach and a novel reachability condition of the composite sliding surfaces is established. The resultant dynamics are proved to be globally asymptotically stable. Simulations show the efficacy of the proposed scheme. 相似文献
35.
Many video-based techniques for assessing postures at work have been developed. Choosing the most appropriate technique should be based on an evaluation of different alternatives in terms of their ability to produce posture information at low input costs, i.e. their cost efficiency. This study compared four video-based techniques for assessing upper arm postures, using cost and error data from an investigation on hairdressers. Labour costs associated with the posture assessments from the video recordings were the dominant factor in the cost efficiency comparison. Thus, a work sampling technique associated with relatively large errors appeared, in general, to be the most cost-efficient because it was labour-saving. Measurement bias and other costs than labour cost for posture assessment influenced the ranking and economic evaluation of techniques, as did the applied measurement strategy, i.e. the numbers of video recordings and repeated assessments of them. PRACTITIONER SUMMARY: The cost efficiency of four video-based techniques for assessing upper arm postures was compared. Work sampling techniques were in general more cost efficient than continuous observations since they were labour-saving. Whilst a labour cost dominated the comparison, 'hidden costs', bias and measurement strategy also influenced this dominance. 相似文献
36.
K. T. Ewida H. El-Salmawy N. N. Atta M. M. Mahmoud 《Clean Technologies and Environmental Policy》2006,8(3):188-197
A technique for controlled burning of rice straw is presented. It relies on well-designed rice straw pellets to be burned in fluidized bed. The developed pellets have high burning rate, no fly ashes emissions and minimum bed fouling. The pellets are manufactured from ground rice straw in a disc pelletizer with the aid of bonding and suitable additive materials. The pellets are tested under controlled conditions in a test rig, which represents a single pellet fluidized bed. It is equipped with a nitrogen gun to eject the pellet and freeze the reaction at any predetermined time during combustion. The ejected pellets are weighed as well as elementary analyzed for both carbon and hydrogen, to calculate the burning rate as well as the combustion efficiency, respectively. The effect of several parameters has been evaluated including straw particle size, pellet size, type and concentration of bonding material as well as anti-sintering additives. Also, the pellets’ mechanical characteristics have been evaluated. It has been found that char combustion phase represents the controlling phase of the pellet combustion. The burning rate is higher as the void fraction of the pellet is higher. Starch showed better combustion and mechanical characteristics out of the five tested bonding materials. Adding kaolin to the pellets results in improving the sintering characteristics of the pellets. The experimental results were compared with two combustion models: the oxygen diffusion controlled and the kinetic-diffusion models. It has been found that oxygen diffusion controlled model more accurately simulates the combustion of the pellet during its char combustion phase. The model has been used to evaluate the effect of some operational parameters on the pellet combustion characteristics such as bed temperature, gas flow and oxygen concentration. 相似文献
37.
Amro A. El-Baz M. Kamal T. Ewida M. Abbas Shouman Mahmoud M. El-Halwagi 《Clean Technologies and Environmental Policy》2005,7(2):78-86
The objective of this paper is to develop a systematic methodology for mass integration in drain systems and watersheds. Mass integration is a holistic approach to the tracking, transformation, and allocation of species and streams. The watershed and drain system is first discretized into reaches. The MFA model developed in part I of this work (Simulation and Application to Ammonium Management in Bahr El-Baqar Drain System) is used to describe the environmental phenomena that affect the fate and transport of targeted species and the operators that characterize the system inputs and outputs as they relate to the surroundings. Next, we develop an integration framework which encompasses sources, sinks, and interception technologies to aid in the development for nitrogen-management strategies. The simulation model was transformed into a synthesis model by introducing optimization variables and including models for the potential management strategies. The problem of minimizing negative environmental impact subject to technical, social, economic, and regulatory constraints was posed as a nonlinear optimization program whose solution identified and synthesized the most effective solution strategies. These mathematical models and management strategies were coded into a computer-aided tool using LINGO programming platform. The program can be readily modified to address a variety of cases. Tradeoffs and sensitivity analysis were established using the devised model. The devised framework was applied to an Egyptian drain system (Bahr El-Baqar) along with the outfall to Lake Manzala. The results of the case study provide solution strategies for nitrogen management along with their technical, economic, and environmental implications. 相似文献
38.
Transmission pricing has become a major issue in the discussions about the deregulated electricity markets.Consequently,open access to the transmission system is one of the basic topics to allow competition among participants in the energy market.Transmission costs have an important impact on relative competition among participants in the energy market as well as on short-and long-term economic efficiencies of the whole electricity industry,although they represent only close to 10% of the energy market price.This paper deals with the design and tests of a transmission pricing method based on the optimal circuit prices derived from the economically adapted network(EAN).Prices derived from the EAN have the advantage of being in tune with the maximum revenue allowed to the owner of transmission assets and simplifying the optimal allocation of transmission costs among participants.Beginning from the conceptual design,the proposed method is tested on a three-bus network and on the IEEE 24-bus reliability test system. 相似文献
39.
Walaa Mahmoud Shehata Abeer Mahmoud Shoaib Fatma Khalifa Gad 《Egyptian Journal of Petroleum》2018,27(4):553-565
Inter-plant hydrogen integration (IPHI) is getting more attention in recent years, as a result of the increasing demand for hydrogen in refinery processes, such as hydrotreating and hydrocracking. In this work, IPHI with regeneration scheme is analyzed. Indirect integration scheme is adopted, where hydrogen sources from different hydrogen networks are integrated via a centralized purifier, such as pressure swing adsorption (PSA) or membrane separation. The introduced model is able to select the optimum interception unit, which minimizes the total annualized cost. Besides, multi-period consideration is included in the analysis to address the effect of changes in operating conditions of the IPHI network on total hydrogen consumption. Two case studies are presented to demonstrate the applicability and usefulness of the proposed model. 相似文献
40.
Branch and bound algorithms for Mixed-Integer Linear Programming (MILP) almost universally branch on a single variable to create disjunctions. General linear expressions involving multiple variables are another option for branching disjunctions, but are not used for two main reasons: (i) descendent LPs tend to solve more slowly because of the added constraints, so the overall solution time is increased, and (ii) it is difficult to quickly find an effective general disjunction. We study the use of general disjunctions to reach the first MILP-feasible solution quickly, showing for the first time that general disjunctions can provide speed improvements for hard MILP models. The speed-up is due to new and efficient ways to (i) trigger the inclusion of a general disjunction only when it is likely to be beneficial, and (ii) construct effective general disjunctions very quickly. Our empirical results show performance improvements versus a state of the art commercial MILP solver. 相似文献