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In this article, we report the synthesis and biological properties of a series of novel oxazepines related to isoCA-4 having significant antitumor properties. Among them, three oxazepin-9-ol derivatives display a nanomolar or a sub-nanomolar cytotoxicity level against five human cancer cell lines (HCT116, U87, A549, MCF7, and K562). It was demonstrated that the lead compound in this series inhibits tubulin assembly with an IC50 value of 1 μM and totally arrests the cellular cycle in the G2/M phase at the low concentration of 5 nM in HCT116 and K562 cells. Molecular modeling studies perfectly corroborates these promising results.  相似文献   
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In this paper, the compression of multispectral images is addressed. Such 3-D data are characterized by a high correlation across the spectral components. The efficiency of the state-of-the-art wavelet-based coder 3-D SPIHT is considered. Although the 3-D SPIHT algorithm provides the obvious way to process a multispectral image as a volumetric block and, consequently, maintain the attractive properties exhibited in 2-D (excellent performance, low complexity, and embeddedness of the bit-stream), its 3-D trees structure is shown to be not adequately suited for 3-D wavelet transformed (DWT) multispectral images. The fact that each parent has eight children in the 3-D structure considerably increases the list of insignificant sets (LIS) and the list of insignificant pixels (LIP) since the partitioning of any set produces eight subsets which will be processed similarly during the sorting pass. Thus, a significant portion from the overall bit-budget is wastedly spent to sort insignificant information. Through an investigation based on results analysis, we demonstrate that a straightforward 2-D SPIHT technique, when suitably adjusted to maintain the rate scalability and carried out in the 3-D DWT domain, overcomes this weakness. In addition, a new SPIHT-based scalable multispectral image compression algorithm is used in the initial iterations to exploit the redundancies within each group of two consecutive spectral bands. Numerical experiments on a number of multispectral images have shown that the proposed scheme provides significant improvements over related works.  相似文献   
4.
In order to strengthen their security issues, electrical companies devote particular efforts to developing and enhancing their fraud detection techniques that cope with the information and communication technologies integration in smart grid fields. Having been treated earlier by several researchers, various detection schemes adapted from attack models that benefit from the smart grid topologies weaknesses, aiming primarily to the identification of suspicious incoming hazards. Wireless meshes have been extensively used in smart grid communication architectures due to their facility, lightness of conception and low cost installation; however, the communicated packets are still exposed to be intercepted maliciously in order either to falsify pertinent information like the smart meter readings, or to inject false data instead, aiming at electricity theft during the communication phase. For this reason, this paper initiates a novel method based on RSA cryptographic algorithm to detect electricity fraud in smart grid. This new method consists of generating two different cryptograms of one electricity measurement before sending, after which the recipient is used to find the same value after decrypting the two cyphers in a normal case. Otherwise, a fraudulent manipulation could occur during the transmission stage. The presented method allows us to kill two birds with one stone. First, satisfactory outcomes are shown: the algorithm accuracy reaches 100%, from one hand, and the privacy is protected thanks to the cryptology concept on the other hand.  相似文献   
5.
Wireless Sensor Network (WSN) forms an essential part of IoT. It is embedded in the target environment to observe the physical parameters based on the type of application. Sensor nodes in WSN are constrained by different features such as memory, bandwidth, energy, and its processing capabilities. In WSN, data transmission process consumes the maximum amount of energy than sensing and processing of the sensors. So, diverse clustering and data aggregation techniques are designed to achieve excellent energy efficiency in WSN. In this view, the current research article presents a novel Type II Fuzzy Logic-based Cluster Head selection with Low Complexity Data Aggregation (T2FLCH-LCDA) technique for WSN. The presented model involves a two-stage process such as clustering and data aggregation. Initially, three input parameters such as residual energy, distance to Base Station (BS), and node centrality are used in T2FLCH technique for CH selection and cluster construction. Besides, the LCDA technique which follows Dictionary Based Encoding (DBE) process is used to perform the data aggregation at CHs. Finally, the aggregated data is transmitted to the BS where it achieves energy efficiency. The experimental validation of the T2FLCH-LCDA technique was executed under three different scenarios based on the position of BS. The experimental results revealed that the T2FLCH-LCDA technique achieved maximum energy efficiency, lifetime, Compression Ratio (CR), and power saving than the compared methods.  相似文献   
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Journal of Materials Science - The CuFeCr0.5Ni0.5O4 (CFO) compound was synthesized using sol–gel reaction combustion technic. The structural analysis showed that the obtained composites have...  相似文献   
7.
Multimedia Tools and Applications - In this paper, a robust additive image watermarking system operating in the Dual Tree Complex Wavelet Transform (DTCWT) domain is proposed. The system takes...  相似文献   
8.
The influence of quenched disorder on the structural properties and on low-temperature field-dependent magnetization, in terms of the spin-wave theory, of (La1?x Nd x )2/3(Ca1?y Sr y )1/3MnO3 with J 1 (x=0,y=0); J 2 (x=0.05,y=0.04); J 3 (x=0.25,y=0.20); J 4 (x=0.3,y=0.24); J 5 (x=0.98,y=0.8) is investigated by characterizing a series of samples with the same A-site cational mean radius and the same average valence of the Mn ion but different A-site ionic radii variance. Our results demonstrate that moderate-small chemical disorder does not affect the crystallographic structure, but enhance the random local distortion of MnO6 octhaedra. Magnetization measurements show that the Curie temperature (T C ) decreases with disorder. The evolution of the saturation magnetization with the disorder cannot be deduced due to the possible contribution of the Nd spins to the total magnetic moment. The thermal evolution of magnetization in the ferromagnetic phase at low temperature varies as T 3/2, in accordance with Bloch’s law. The spin wave stiffness constant D obtained from the Bloch constant is found to decrease with the increase of disorder. We found that for the range of the study disorder, the magnetic behavior corresponds to a conventional ferromagnet, where T C should be proportional to D.  相似文献   
9.
Mobile Networks and Applications - With the rapid development in wireless technologies and the Internet, the Internet of Things (IoT) is envisioned to be an integral part of our daily lives....  相似文献   
10.
Only recently has increasing use been made of computer simulation in the field of extruder engineering. This simulation is based on physico-mathematical process models. In order to achieve a closed, process engineering-based extruder layout and operating behavior simulation it is necessary to have models describing the throughput behavior, the melting process, the temperature development, the pressure profile over the screw length, the residence time distribution, the mixing and dispersion processes, and also the torque and power requirements. In the Plastics Technology Section of the University of Paderborn (KTP) a program for the computer-aided design of extruders (REX), financed by 17 companies, was developed which will permit rapid application of the models developed there and will fulfill the requirements set out above. Since no computation-intensive numerical methods like Finite Element or Finite Difference Methods (FEM, FDM) are required, the algorithms are very rapid, which means that short computing times are achieved (just a few seconds on an IBM AT).  相似文献   
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