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41.
1 IntroductionRecently ,DirectSequencespreadCodeDivisionMultipleAccess (DS CDMA)hasbecomealeadingmultipleaccesstechnologyforcellularwirelesssys tems,inwhichtherehavebeensignificantchieve ments.Intheliterature ,therehavebeenresearchesonpowercontrolalgorithm…  相似文献   
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Hepatocellular carcinoma (HCC) is the most common primary malignancy of the liver and is one of the leading causes of cancer-related deaths worldwide. Regorafenib, a multi-kinase inhibitor, is used as a second-line treatment for advanced HCC. Here, we aimed to investigate the mechanism of the antitumor effect of regorafenib on HCC and evaluate altered microRNA (miRNA) expression. Cell proliferation was examined in six HCC cell lines (HuH-7, HepG2, HLF, PLC/PRF/5, Hep3B, and Li-7) using the Cell Counting Kit-8 assay. Xenografted mouse models were used to assess the effects of regorafenib in vivo. Cell cycle analysis, western blotting analysis, and miRNA expression analysis were performed to identify the antitumor inhibitory potential of regorafenib on HCC cells. Regorafenib suppressed proliferation in HuH-7 cell and induced G0/G1 cell cycle arrest and cyclin D1 downregulation in regorafenib-sensitive cells. During miRNA analysis, miRNA molecules associated with the antitumor effect of regorafenib were found. Regorafenib suppresses cell proliferation and tumor growth in HCC by decreasing cyclin D1 via alterations in intracellular and exosomal miRNAs in HCC.  相似文献   
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Next generation wireless communication is based on a global system of fixed and wireless mobile services thatare transportable across different network back-bones,network service providers and network geographical boundaries.This paper presents an approach to investigate the effects of soft handover and perfect power control on the forward link ina DS-CDMA cellular system.Especially,the relationships between the size ofhandover zone and the capacity gain are e-valuated under the log-normal shadow channel.Then the optimization of maximum forward capacity is very necessary tobe done with the maximum size of soft handover zone to the various system characteristics.  相似文献   
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This paper presents an implementation scheme of Motion-JPEG2000 (MJP2) integrated with invertible deinterlacing. In previous work, we developed an invertible deinterlacing technique that suppresses the comb-tooth artifacts which are caused by field interleaving for interlaced scanning videos, and affect the quality of scalable frame-based codecs, such as MJP2. Our technique has two features, where sampling density is preserved and image quality is recovered by an inverse process. When no codec is placed between the deinterlacer and inverse process, the original video is perfectly reconstructed. Otherwise, it is almost completely recovered. We suggest an application scenario of this invertible deinterlacer for enhancing the sophisticated signal-to-noise ratio scalability in the frame-based MJP2 coding. The proposed system suppresses the comb-tooth artifacts at low bitrates, while enabling the quality recovery through its inverse process at high bitrates within the standard bitstream format. The main purpose of this paper is to present a system that yields high quality recovery for an MJP2 codec. We demonstrate that our invertible deinterlacer can be embedded into the discrete.wavelet transform employed in MJP2. As a result, the energy gain factor to control rate-distortion characteristics can be compensated for optimal compression. Simulation results show that the recovery of quality is improved by, for example, more than 2.0 dB in peak signal-to-noise ratio by applying our proposed gain compensation when decoding 8-bit grayscale Football sequence at 2.0 bpp.  相似文献   
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This paper proposes a directional design method of 2-D nonseparable linear-phase paraunitary filter banks. The proposed method is based on a lattice structure consisting of the 2-D separable DCT block and nonseparable support extension processes. Because of the nonseparability, the bases are allowed to be directional with the critically fixed subsampling, overlapping, orthogonal, symmetric, real-valued, and compact support properties. First, a novel vanishing moment (VM) condition is introduced as a suitable directional constraint, where the moment is referred to as the trend VM. The condition forces wavelet filters, i.e., high-pass and bandpass filters, to annihilate trend-surface components. Second, some theoretical properties of TVMs are discussed for general 2-D paraunitary systems, and then, the properties are applied to the lattice parameters. In order to verify the significance, several design examples are shown, the trend-surface annihilation properties are numerically confirmed, and the denoising capability is evaluated for images through shrinkage. It is shown that our proposed transforms yield perceptually preferable results.  相似文献   
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The amyloid fibril is a misfolded and undesirable state for proteins that has been proposed to be a causative agent for a variety of fatal diseases known as amyloid diseases, such as Alzheimer's and prion diseases. However, the fibril has a highly ordered tertiary structure in which numerous beta-strand polypeptide chains align in a regular pattern. Thus, this kind of fibril has the potential to be engineered into proteinaceous materials. Amyloid fibrils of misfolded proteins primarily comprise a single polypeptide species, that is, the self-assembly is homogeneous. We here found that three or four designed peptides can assemble heterogeneously and cooperatively into amyloid fibrils, a process accompanied by a drastic secondary structural transition from alpha helix to beta sheet. Heterogeneous assembly into fibrils is accomplished by complementary electrostatic interactions between three or four peptide species, each of which is not able to self-assemble homogeneously. These findings will lead to a novel way to study the molecular details of amyloid formation and also to design beta-sheet peptidyl materials.  相似文献   
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The sequencing of the human genome has been successfully completed and offers the chance of obtaining a large amount of valuable information for understanding complex cellular events simply and rapidly in a single experiment. Interestingly, in addressing these proteomic studies, the importance of protein-detecting microarray technology is increasing. In the coming few years, microarray technology will become a significantly promising and indispensable research/diagnostic tool from just a speculative technology. It is clear that the protein-detecting microarray is supported by three independent but strongly related technologies (surface chemistry, detection methods, and capture agents). Firstly, a variety of surface-modification methodologies are now widely available and offer site-specific immobilization of capture agents onto surfaces in such a way as to keep the native conformation and activity. Secondly, sensitive and parallel detection apparatuses are being developed to provide highly engineered microarray platforms for simultaneous data acquisition. Lastly, in the development of capture agents, antibodies are now probably the most prominent capture agents for analyzing protein abundances. Alternative scaffolds, such as phage-displayed antibody and protein fragments, which provide the advantage of increasing diversity of proteinic capture agents, however, are under development. An approach involving recombinant proteins fused with affinity tag(s) and coupled with a highly engineered surface chemistry will provide simple production protocols and specific orientations of capture agents on the microarray formats. Peptides and other small molecules can be employed in screening highly potent ligands as well as in measuring enzymatic activities. Protein-detecting microarrays supported by the three key technologies should contribute in accelerating diagnostic/biological research and drug discovery.  相似文献   
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