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1.
A hierarchical scheme for elastic graph matching applied to hand gesture recognition is proposed. The proposed algorithm exploits the relative discriminatory capabilities of visual features scattered on the images, assigning the corresponding weights to each feature. A boosting algorithm is used to determine the structure of the hierarchy of a given graph. The graph is expressed by annotating the nodes of interest over the target object to form a bunch graph. Three annotation techniques, manual, semi-automatic, and automatic annotation are used to determine the position of the nodes. The scheme and the annotation approaches are applied to explore the hand gesture recognition performance. A number of filter banks are applied to hand gestures images to investigate the effect of using different feature representation approaches. Experimental results show that the hierarchical elastic graph matching (HEGM) approach classified the hand posture with a gesture recognition accuracy of 99.85% when visual features were extracted by utilizing the Histogram of Oriented Gradient (HOG) representation. The results also provide the performance measures from the aspect of recognition accuracy to matching benefits, node positions correlation and consistency on three annotation approaches, showing that the semi-automatic annotation method is more efficient and accurate than the other two methods.  相似文献   
2.
Document image binarization involves converting gray level images into binary images, which is a feature that has significantly impacted many portable devices in recent years, including PDAs and mobile camera phones. Given the limited memory space and the computational power of portable devices, reducing the computational complexity of an embedded system is of priority concern. This work presents an efficient document image binarization algorithm with low computational complexity and high performance. Integrating the advantages of global and local methods allows the proposed algorithm to divide the document image into several regions. A threshold surface is then constructed based on the diversity and the intensity of each region to derive the binary image. Experimental results demonstrate the effectiveness of the proposed method in providing a promising binarization outcome and low computational cost.  相似文献   
3.
Journal of Mechanical Science and Technology - Multi-rotor unmanned aerial vehicles (UAVs) are being widely used in various military and civilian fields because they can replace manned systems in...  相似文献   
4.
With the aim of discovering new anticancer agents, we have designed and synthesized novel α-aminophosphonate derivatives containing a 2-oxoquinoline structure using a convenient one-pot three-component method. The newly synthesized compounds were evaluated for antitumor activities against the A549 (human lung adenocarcinoma cell), HeLa (human cervical carcinoma cell), MCF-7 (human breast cancer cell), and U2OS (human osteosarcoma cell) cancer cell lines in vitro, employing a standard 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay. The results of pharmacological screening indicated that many compounds exhibited moderate to high levels of antitumor activities against the tested cancer cell lines and that most compounds showed more potent inhibitory activities comparable to 5-fluorouracil (5-FU) which was used as a positive control. The mechanism of representative compound 4u (diethyl((2-oxo-1,2-dihydroquinolin-3-yl)(phenyl-amino)methyl)phosphonate) indicated that the compound mainly arrested HeLa cells in S and G2 stages and was accompanied by apoptosis in HeLa cells. This action was confirmed by acridine orange/ethidium bromide staining, Hoechst 33342 staining, and flow cytometry.  相似文献   
5.
In this paper, a novel object tracking based on a particle filter and speeded up robust feature(SURF) is proposed, which uses both color and SURF features. The SURF feature makes the tracking result more robust. On the other hand, the particle selection can lead to save time. In addition, we also consider the matched particle applicable to calculating the SURF weight. Owing to the color, spatial, and SURF features being adopted, this method is more robust than the traditional color-based appearance model. Experimental results demonstrate the robustness and accurate tracking results with challenging sequences.Besides, the proposed method outperforms other methods during the intersection of similar color and object’s partial occlusion.  相似文献   
6.
Continuous-wave green laser-crystallized (CLC) single-grain-like polycrystalline silicon n-channel thin-film transistors (poly-Si n-TFTs) demonstrate the higher electron mobility and turn-on current than excimer laser annealing (ELA) poly-Si n-TFTs. Furthermore, high drain voltage accelerates the flowing electrons in n-type channel, and hence the hot-carriers possibly cause a serious damage near the drain region and deteriorate the source/drain (S/D) current. In this study, at high drain stress voltage, it appears that CLC TFT was degraded in the initial stress time (before 50 s), but the drain current was enhanced after 50 s. After 50 s stress time, the amount of grain boundary trap states near the drain side was getting large and the reflowing holes damaged the source region or injected into gate oxide near source side as well.  相似文献   
7.
This paper reports a novel full-range vacuum pressure sensing device, capable of exceeding the sensing range of most gauges and reducing the volume by a factor of 10. The proposed device gauges the free decay rate of a micro-cantilever beam deflected using electrostatic force and measurements of capacitance are used to determine the free decay rate of the sensing beam with respect to deflection force and vacuum pressure. This novel design enables the full-range measurement of vacuum pressure from 0.2 to 1?×?10?8?torr. The trapezoidal micro-cantilever beam provides uniform in-plane stress across the surface of the beam, while a thick square plate connected to the trapezoid beam serves as a proof mass and receiver of electrostatic force. Results demonstrate that the free decay rate of the deflected beam is linearly proportional to vacuum pressure. The decay time constant was 0.69?s under low vacuum and 42.56?s under high vacuum. In addition, a change in vacuum pressure of one torr resulted in a change of 47.6 (1/s) in the decay rate. This rapid response to changes in pressure demonstrates the high degree of sensitivity demonstrated by the device. The proposed device represents a considerable advancement in the development of miniature full-range pressure gauges as well as the applicability of micro-electromechanical systems.  相似文献   
8.
9.
变频器在热力站定压补水中的应用   总被引:1,自引:0,他引:1  
文中介绍了丹佛斯Danfoss新型变频器VLT8000 AQUA的特点,阐述了定压补水控制的基本原理,设计了变频定压补水系统的控制方案,进行了变频定压补水系统的性能分析和经济效益分析.实际运行表明,系统运行稳定、可靠、节能.  相似文献   
10.
A capacitive micromachined ultrasonic transducer (CMUT) array for minimally invasive medical diagnosis has been developed. Unlike traditional ultrasonic transducers, which generally use a bulky piece of substrate, this transducer array was integrated on a 40--thick micromachined silicon substrate into a probe shape with a typical shank width of 50-80 and a shank length of 4-8 mm. For 1-D arrays, 24-96 CMUT devices were integrated on one such silicon probe and formed an accurately configured phase array. In addition to miniaturization, reduction of the substrate thickness also decreases the intertransducer crosstalk due to substrate Lamb waves. Due to its miniature size, this array can be placed or implanted close to the target tissue/organ and can perform high-resolution high-precision diagnosis and stimulation using high-frequency ultrasounds. The issue of conflict between resolution and penetration depth of ultrasonic diagnosis can therefore be resolved. A two-layer polysilicon surface micromachining process was used to fabricate this device. Suspended polysilicon membranes of diameters ranging from 20 to 90 and thicknesses from 1.0 to 2.5 were used to generate and detect ultrasounds of frequencies ranging from 1 to 10 MHz. B-mode imaging using this transducer array has been demonstrated.  相似文献   
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