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1.
A novel circuit for realising negative immittance using a single plus-type second-generation current conveyor is proposed. The immittance values of the the circuit, which only use four passive elements, can be orthogonally adjusted. The circuit does not require component matching  相似文献   
2.
Due to the potential wide deployment of Radio Frequency Identification (RFID), the security of RFID systems has drawn extensive attention from both academia and industry, and the RFID authentication protocol is an important mechanism in the security of RFID systems. The desired security requirements of RFID authentication protocols include privacy, integrity, authentication, anonymity/untraceability, and even availability. To design an efficient protocol that satisfies all the requirements with limited resources is a challenge. This paper proposes a new RFID authentication protocol based on Error Correction Codes (ECC). The proposed scheme has excellent performance in terms of security, efficiency, server’s maintenance, robustness, and cost. The tag only performs simple operations, such as random number generation and simple bitwise computations. The lightweight feature makes it attractive to those low-cost RFIDs that support only simple operations.  相似文献   
3.
This work proposes a novel approach to translate Chinese to Taiwanese sign language and to synthesize sign videos. An aligned bilingual corpus of Chinese and Taiwanese sign language (TSL) with linguistic and signing information is also presented for sign language translation. A two-pass alignment in syntax level and phrase level is developed to obtain the optimal alignment between Chinese sentences and Taiwanese sign sequences. For sign video synthesis, a scoring function is presented to develop motion transition-balanced sign videos with rich combinations of intersign transitions. Finally, the maximum a posteriori (MAP) algorithm is employed for sign video synthesis based on joint optimization of two-pass word alignment and intersign epenthesis generation. Several experiments are conducted in an educational environment to evaluate the performance on the comprehension of sign expression. The proposed approach outperforms the IBM Model2 in sign language translation. Moreover, deaf students perceived sign videos generated by the proposed method to be satisfactory  相似文献   
4.
Mining Web informative structures and contents based on entropy analysis   总被引:3,自引:0,他引:3  
We study the problem of mining the informative structure of a news Web site that consists of thousands of hyperlinked documents. We define the informative structure of a news Web site as a set of index pages (or referred to as TOC, i.e., table of contents, pages) and a set of article pages linked by these TOC pages. Based on the Hyperlink Induced Topics Search (HITS) algorithm, we propose an entropy-based analysis (LAMIS) mechanism for analyzing the entropy of anchor texts and links to eliminate the redundancy of the hyperlinked structure so that the complex structure of a Web site can be distilled. However, to increase the value and the accessibility of pages, most of the content sites tend to publish their pages with intrasite redundant information, such as navigation panels, advertisements, copy announcements, etc. To further eliminate such redundancy, we propose another mechanism, called InfoDiscoverer, which applies the distilled structure to identify sets of article pages. InfoDiscoverer also employs the entropy information to analyze the information measures of article sets and to extract informative content blocks from these sets. Our result is useful for search engines, information agents, and crawlers to index, extract, and navigate significant information from a Web site. Experiments on several real news Web sites show that the precision and the recall of our approaches are much superior to those obtained by conventional methods in mining the informative structures of news Web sites. On the average, the augmented LAMIS leads to prominent performance improvement and increases the precision by a factor ranging from 122 to 257 percent when the desired recall falls between 0.5 and 1. In comparison with manual heuristics, the precision and the recall of InfoDiscoverer are greater than 0.956.  相似文献   
5.
Power management has increased its significance in mobile communications along with the growing population of mobile users and wireless connectivity. In this paper we propose a smart scheduling algorithm in Android network kernel to increase power efficiency. As periodically-updating applications start sync with a DNS query packet, we defer the packets in order to make these applications synchronize from smaller time difference to finally simultaneously. To implement the idea, we design the algorithm for two or more applications in this paper. This algorithm is composed of several mechanisms: approaching, aligning, and maintaining. By experiments we show the practicability and the comparison between the energy saving ratios in different scenarios.  相似文献   
6.
Primary liver cancer accounts for the third most deadly type of malignant tumor globally, and approximately 80% of the cases are hepatocellular carcinoma (HCC), which highly relies on the activity of hypoxia responsive pathways to bolster its metastatic behaviors. MicroRNA-29a (MIR29A) has been shown to exert a hepatoprotective effect on hepatocellular damage and liver fibrosis induced by cholestasis and diet stress, while its clinical and biological role on the activity hypoxia responsive genes including LOX, LOXL2, and VEGFA remains unclear. TCGA datasets were retrieved to confirm the differential expression and prognostic significance of all genes in the HCC and normal tissue. The Gene Expression Omnibus (GEO) dataset was used to corroborate the differential expression and diagnostic value of MIR29A. The bioinformatic identification were conducted to examine the interaction of MIR29A with LOX, LOXL2, and VEGFA. The suppressive activity of MIR29A on LOX, LOXL2, and VEGF was verified by qPCR, immunoblotting, and luciferase. The effect of overexpression of MIR29A-3p mimics in vitro on apoptosis markers (caspase-9, -3, and poly (ADP-ribose) polymerase (PARP)); cell viability and wound healing performance were examined using immunoblot and a WST-1 assay and a wound healing assay, respectively. The HCC tissue presented low expression of MIR29A, yet high expression of LOX, LOXL2, and VEGFA as compared to normal control. Serum MIR29A of HCC patients showed decreased levels as compared to that of normal control, with an area under curve (AUC) of 0.751 of a receiver operating characteristic (ROC) curve. Low expression of MIR29A and high expression of LOX, LOXL2, and VEGFA indicated poor overall survival (OS). MIR29A-3p was shown to target the 3′UTR of LOX, LOXL2, and VEGFA. Overexpression of MIR29A-3p mimic in HepG2 cells led to downregulated gene and protein expression levels of LOX, LOXL2, and VEGFA, wherein luciferase reporter assay confirmed that MIR29A-3p exerts the inhibitory activity via directly binding to the 3′UTR of LOX and VEGFA. Furthermore, overexpression of MIR29A-3p mimic induced the activity of caspase-9 and -3 and PARP, while it inhibited the cell viability and wound healing performance. Collectively, this study provides novel insight into a clinical-applicable panel consisting of MIR29, LOX, LOXL2, and VEGFA and demonstrates an anti-HCC effect of MIR29A via comprehensively suppressing the expression of LOX, LOXL2, and VEGFA, paving the way to a prospective theragnostic approach for HCC.  相似文献   
7.
The rearrangement of mirror elements has been presented. By virtue of the proposed approach, new topologies realizing the same transfer function as the initial circuit can be obtained. Moreover, we may derive the circuits with improved properties than the original circuit. A practical example has been given to demonstrate the feasibility.  相似文献   
8.
Based on the fabrication of Ag nanoparticles (NPs) with controlled geometry and surface density on an InGaN/GaN quantum well (QW) epitaxial structure, which contains indium-rich nano-clusters for producing localized states and free-carrier (delocalized) states in the QWs, and the characterization of their localized surface plasmon (LSP) coupling behavior with the carriers in the QWs, the interplay behavior of LSP coupling with carrier delocalization in the QWs is demonstrated. By using the polystyrene nanosphere lithography technique with an appropriate nanosphere size and adjusting the post-fabrication thermal annealing condition, the induced LSP resonance wavelength of the fabricated Ag NPs on the QW sample can match the QW emission wavelength for generating the coherent coupling between the carriers in the QWs and the induced LSP. The coupling leads to the enhancement of radiative recombination rate in the QWs and results in increased photoluminescence (PL) intensity, red-shifted PL spectrum, reduced PL decay time, and enhanced internal quantum efficiency. It is found that the observed effects are mainly due to the LSP coupling with the delocalized carriers in the QWs.  相似文献   
9.
IEEE 802.16j Mobile Multihop Relay Standard defines multi-hop relay operation in a WiMAX system. It uses a novel synchronous multicast and broadcast transmission mechanism to achieve macro diversity. With the newly introduced synchronous delivery constraint, the multicast data delivery algorithm should be designed differently to enhance system performance. This paper provides Multi-Rate Selection Algorithm (MRSA) for multicast and broadcast (MBS) data delivery. It could reduce the data distribution delay from the BS to all the RSs. Besides, we also propose the path selection algorithm to further improve the effectiveness of MRSA. Our simulation results show that using MRSA with our shortest-path path selection algorithm, the delay for data delivery in 802.16j MBS system could be greatly reduced. The proposed scheme could achieve the performance closed to the optimal solutions. To the authors’ best knowledge, this is the first research work to investigate the IEEE 802.16j multicast and broadcast problem.  相似文献   
10.
Traditional wireless communications only utilize fixed-rate multicast and broadcast. In other words, only the most robust modulation and coding scheme can be applied for data transmission. Such a scheme fails to sufficiently exploit the potential gains of multicast and broadcast, resulting in bandwidth waste. To overcome such a problem, investigating the rate adaptation of multicast and broadcast wireless systems is the primary task. Unlike the traditional wireless systems, this paper presents an analytical model with rate adaptation for both multicast and broadcast. Adaptive modulation and coding are applied to achieve rate adaptation. We construct a stochastic model by using Finite State Markov chains for the multicast broadcast system modeling. The model’s outputs are shown to approximate to the results of our system level simulations. The model derives the performance of rate adaptation in multicast and broadcast. With the deduced modeling results, we can predict the system throughput providing the channel states, and the modulation and coding schemes variations.  相似文献   
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