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111.
Social media has emerged as a significant and effective means of assisting and endorsing activities and communications among peers, consumers and organizations that outdo the restrictions of time and space. While the previous studies acknowledge the role of agents of culture change, it largely remains silent on the role of social media in influencing acculturation outcomes and consumption choices. This study uses self-administered questionnaire to collect data from 514 Turkish-Dutch respondents and examines how their use of social media affects their acculturation and consumption choices. This research makes a significant contribution to consumer acculturation research by showing that social media is a vital means of culture change and a driver of acculturation strategies and consumption choices. This study is the first to investigate the role of social media as an agent of culture change in terms of how it impacts acculturation and consumption. The paper discusses implications for theory development and for practice.  相似文献   
112.
This article describes the application of a multiobjective evolutionary algorithm for locating roadside infrastructure for vehicular communication networks over realistic urban areas. A multiobjective formulation of the problem is introduced, considering quality‐of‐service and cost objectives. The experimental analysis is performed over a real map of Málaga, using real traffic information and antennas, and scenarios that model different combinations of traffic patterns and applications (text/audio/video) in the communications. The proposed multiobjective evolutionary algorithm computes accurate trade‐off solutions, significantly improving over state‐of‐the‐art algorithms previously applied to the problem.  相似文献   
113.
Key relationships between molecular structure and final properties are reported for standard flow and high flow grades of commercially‐available polyetheretherketone (PEEK) resins that differ primarily in molecular weight and molecular weight distribution. Despite similar chemistry and composition, the molecular size‐dependent structural differences associated with the PEEK resins in this study are shown to influence the crystallization rate, final crystallinity, and melt rheology during processing, which subsequently affects mechanical properties, including strength, ductility, and impact resistance. These structure‐property relationships provide fundamental understanding to aid in the design and manufacturing of industrial and medical devices that leverage both the advantages common to all PEEK resins, including chemical and thermal resistance, mechanical strength, and biocompatibility, as well as more subtle differences in crystallization kinetics, melt rheology, ductility, and impact resistance. POLYM. ENG. SCI., 57:955–964, 2017. © 2016 Society of Plastics Engineers  相似文献   
114.
This paper presents new topologies for emulating floating immittance functions using three to five passive elements and only two current-feedback operational-amplifiers (CFOAs). The feasibility of using only two CFOAs and two passive components is explored. The proposed topologies can emulate lossy positive and negative inductances and capacitance-, inductance-, resistance-multipliers, and frequency dependent negative and positive conductances. The functionality of the proposed circuits was experimentally verified using the commercially available AD844 CFOA. The experimental results are in excellent agreement with theoretical calculations.  相似文献   
115.
In view of the desire to improve the water quality of the heavily polluted branches of the Shatt al-Arab River at the City of Basrah, it was proposed to maintain effective flushing as well as contracting sewerage system. The present study was conducted in order to examine the water quality of these branches in an attempt to evaluate the effectiveness of the proposed flushing system. It has been found that their waters contained very low levels of dissolved oxygen and relatively high amounts of both COD and BOD5. The annual average water quality parameters for Basrah Branches were: dissolved oxygen 3.4 ppm; pH 7.67; hydrogen sulphide 1.4 ppm; ammonia 97 μg-at. N l−1; COD 15.9 mg l−1; BOD5 12.7 mg l−1; dissolved silicates 202 μg-at. Si l−1; dissolved reactive phosphate 13.4 μg-at. P-PO43− l−1; nitrate 10.4 μg-at. N-NO3 l−1; nitrite 2.1 μg-at. N-NO2 l−1 and chlorophyll-α 14.3 mg m−3. Based on our calculations, it has been concluded that the proposed system is effective, thus within a flushing cycle all of the above mentioned parameters will become within the acceptable values of the Shatt al-Arab water quality. Moreover, this system has no appreciable effect upon the water quality characteristics of the Shatt al-Arab River due to the fact that it discharges a high volume of water annually. However, It has been recommended to dredge the deposited sludge to a minimum depth of 50 cm.  相似文献   
116.
In this paper, a new autofocus algorithm is presented for back-projection (BP) image formation of synthetic aperture radar (SAR) imaging. The approach is based on maximizing a cost function obtained by prominent points in different sub-apertures of constructed SAR image by varying the flight trajectory parameters. While image-quality-based autofocus approach together with BP algorithm can be computationally intensive, we use approximations that allow optimal corrections to be derived. The approach is applicable for focusing different signal processing algorithms by obtaining modified flight trajectory parameters. Different examples demonstrate the effectiveness of the new autofocus approach applied to the frequency modulated continuous wave mode SAR dataset.  相似文献   
117.
We present a new method to correct eye movement artifacts in electroencephalogram (EEG) data. By using an eye tracker, whose data cannot be corrupted by any electrophysiological signals, an accurate method for correction is developed. The eye-tracker data is used in a Kalman filter to estimate which part of the EEG is of ocular origin. The main assumptions for optimal correction are summed and their validity is proven. The eye-tracker-based correction method is objectively evaluated on simulated data of four different types of eye movements and visually evaluated on experimental data. Results are compared to three established correction methods: Regression, Principal Component Analysis, and Second-Order Blind Identification. A comparison of signal to noise ratio after correction by these methods is given in Table II and shows that our method is consistently superior to the other three methods, often by a large margin. The use of a reference signal without electrophysiological influences, as provided by an eye tracker, is essential to achieve optimal eye movement artifact removal.  相似文献   
118.
Natural radionuclide contents of 226Ra, 228Ra and (40)K were studied for inter-tidal sediments collected from selected locations off the745 km long Balochistan Coast using HPGe detector based gamma-spectrometry system. The sampling zone extends from the beaches of Sonmiani (near Karachi metropolis) through Jiwani (close to the border of Iran). The natural radioactivity levels detected in various sediment samples range from 14.4 +/- 2.5 to 36.6 +/- 3.8 Bq kg(-1) for 226Ra, 9.8 +/- 1.2 to 35.2 +/- 2.0 Bq kg(-1) for (228)Ra and 144.6 +/- 9.4 to 610.5 +/- 23.9 Bq kg(-1) for (40)K. No artificial radionuclide was detected in any of the marine coastal sediment samples. 137Cs, (60)Co, 106Ru and 144Ce contents in sediment samples were below the limit of detection. The measured radioactivity levels are compared with those reported in the literature for coastal sediments in other parts of the world. The information presented in this paper will serve as the first ever local radioactivity database for the Balochistan/Makran Coastal belt of Pakistan. The presented data will also contribute to the IAEA's, Asia-Pacific Marine Radioactivity Database (ASPAMARD) and the Global Marine Radioactivity Database (GLOMARD).  相似文献   
119.
120.
CoSn4 nano-particles were synthesized on Cu and Ni substrates through pulsed current electrodeposition and used as anode in lithium ion batteries. Nano particles with Flower-like morphology were obtained through applying an average current density of 85 mA/cm2 on Ni substrate while the particles formed using constant current electrodeposition are greater in size ca. 500 nm. Optimum discharge capacity of synthesized CoSn4 was obtained 848 mAh g?1 which reduced to 500 mAh g?1 at 120th cycle indicating an enhanced electrochemical performance compared to anode films synthesized through other pulsed current densities and also constant current electrodeposition. This high discharge capacity and cycleability is attributed to finer crystal grains and flower-like morphology of nano particles. Also, the sample synthesized on Ni substrate showed higher cycleability and noticeably lower resistance. High resistance of anode film synthesized on Cu substrate is due to the corrosion and passivation of copper occurred by HF formation in LiPF6 electrolyte.  相似文献   
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