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11.
Considering the robustness, stability and reduced volume of data, researchers have focused on using edge information in various
video processing applications including moving object detection, tracking and target recognition. Though the edge information
is more robust compared to intensity, it also exhibits variations in different frames due to illumination change and noise.
In addition to this, the amount of variation varies from edge to edge. Thus, without making use of this variability information,
it is difficult to obtain an optimal performance during edge matching. However, traditional edge pixel-based methods do not
keep structural information of edges and thus they are not suitable to extract and hold this variability information. To achieve
this, we represent edges as segments that make use of the structural and relational information of edges to allow extraction
of this variability information. During edge matching, existing algorithms do not handle the size, positional and rotational
variations to deal with edges of arbitrary shapes. In this paper, we propose a knowledge-based flexible edge matching algorithm
where knowledge is obtained from the statistics on the environmental dynamics, and flexibility is to deal with the arbitrary
shape and the geometric variations of edges by making use of this knowledge. In this paper, we detailed the effectiveness
of the proposed matching algorithm in moving object detection and also indicated its suitability in other applications like
target detection and tracking. 相似文献
12.
A three-axis SOI accelerometer sensing with both in-plane and vertical comb electrodes 总被引:1,自引:0,他引:1
A three-axis capacitive accelerometer based on silicon-on-insulator is designed and fabricated. In the accelerometer, totally
eight groups of capacitors are compactly arranged around an octagonal proof mass. The four groups of capacitors along orthogonal
direction with in-plane comb electrodes detect XY acceleration, while the other four groups of capacitors along diagonal direction with vertical comb electrodes detect Z acceleration.
Measurements of in-plane and vertical motion by the respective in-plane and vertical comb electrodes enable direct detection
for all the three axes with differential capacitive sensing scheme. For the fabricated accelerometer in the size of 4 × 4 mm2, the capacitance sensitivities of in-plane and out-of-plane accelerometers are 145.3 and 9.1 fF/g, respectively. 相似文献
13.
Detection of epileptic electroencephalogram based on Permutation Entropy and Support Vector Machines 总被引:2,自引:0,他引:2
The electroencephalogram (EEG) has proven a valuable tool in the study and detection of epilepsy. This paper investigates for the first time the use of Permutation Entropy (PE) as a feature for automated epileptic seizure detection. A Support Vector Machine (SVM) is used to classify segments of normal and epileptic EEG based on PE values. The proposed system utilizes the fact that the EEG during epileptic seizures is characterized by lower PE than normal EEG. It is shown that average sensitivity of 94.38% and average specificity of 93.23% is obtained by using PE as a feature to characterize epileptic and seizure-free EEG, while 100% sensitivity and specificity were also obtained in single-trial classifications. 相似文献
14.
15.
Joost Duvigneau Edit Kutnyanszky In Yee Phang Hong-Jing Chung Hairong Wu Lionel Dos Ramos Torben Gädt Siti Fairus M. Yusoff Mark A. Hempenius Ian Manners G. Julius Vancso 《Polymer》2014
We report on the morphology evolution during heating and melting of lamellar poly(isoprene)-block-poly(ferrocenyldimethylsilane) (PI76-b-PFDMS76) raft crystals deposited at the native oxide surface of silicon (SiO2) or at a highly ordered pyrolytic graphite (HOPG) surface, studied by in situ temperature controlled atomic force microscopy. Crystals deposited on hydrophilic SiO2 surfaces revealed an irreversible decrease in length at temperatures of up to tens of degrees above their expected melting temperature, while maintaining their platelet-like structure. Crystals deposited on hydrophobic HOPG surfaces initially decreased in length below their expected melting temperature, while at 120 °C and above a typical molten morphology was observed. In addition, the irreversible formation of a PI76-b-PFDMS76 wetting layer around the crystals was observed upon increasing the temperature. These observations in the morphological behavior upon heating emphasize the role of interfacial energy between a surface deposited block copolymer based macromolecular nanostructure and its supporting substrate. 相似文献
16.
The conflict between agriculture and urban development is intense in urbanizing areas of the United States and is a problem best resolved at the local level. To effectively develop and apply techniques for preserving farmland, areas of conflict must be identified. This article describes the application of a geographic information system (GIS) for determining the location and level of conflict between agriculture and other forms of human intervention. The procedures used for assessing conflicts are described through a case study in the city of Westfield, Massachusetts and the findings show that GIS can be an effective tool for local decision makers, allowing alternative strategies to be developed and evaluated for agricultural protection. 相似文献
17.
Authenticated gum samples from three plant species from Tanzania were analysed and their potential for food, pharmaceutical and other applications was determined by comparing their physicochemical properties with those of commercial Acacia gums from Tanzania, gum karaya and the specifications demanded by the international regulatory bodies for gum arabic for food and pharmaceutical applications. The gum exudate from Dichrostachys cinerea meets some specifications (moisture content, solubility, insoluble matter and ash) demanded for the identity and purity of gum arabic as stipulated by the international regulatory bodies. The aqueous solution of the gum possesses solubility and viscosity similar to commercial gum arabic. Similarly, the properties of Sterculia quinqueloba gum meet a number of the specifications demanded for gum karaya, except that it contains high levels of tannin which would limit its usefulness in food and pharmaceutical applications. The properties of the gum exudate from Acacia pseudofistula, on the other hand, are different from those of Tanzanian commercial Acacia gums. © 2002 Society of Chemical Industry 相似文献
18.
Anh Dinh 《中兴通讯技术(英文版)》2011,9(3):22-27
Most satellite digital radio (SDR) systems use orthogonal frequency-division multiplexing (OFDM) transmission, which means that variable envelope signals are distorted by the RF power amplifier (PA). It is customary to back off the input power to the PA to avoid the PA nonlinear region of operation. In this way, linearity can be achieved at the cost of power efficiency. Another attractive option is to use a linearizer, which compensates for the nonlinear effects of the PA. In this paper, an OFDM transmitter conforming to European Telecommunications Standard Institute SDR Technical Specifications 2007-2008 was designed and implemented on a low-cost field-programmable gate array (FPGA) platform. A weakly nonlinear PA, operating in the L-band SDR frequency, was used for signal transmission. An adaptive linearizer was designed and implemented on the same FPGA device using digital predistortion to correct the undesired effects of the PA on the transmitted signal. Test results show that spectral distortion can be suppressed between 6-9 dB using the designed linearizer when the PA is driven close to its saturation region. 相似文献
19.
One of the main challenges in today's solid oxide fuel cell (SOFC) technology is the reduction of their operating temperature. New types of oxygen ion conducting materials are currently under investigation to overcome the problems which SOFC faces at high temperatures. Samarium doped ceria oxide (SDC) was the material of investigation in this work. Optical quartz (SiO2) and Fe–Ni–Cr alloy (Alloy 600) were the two types of chosen substrates onto which SDC thin films were deposited by e-beam evaporation technique. The bias voltage was applied to the substrate during film growth. It had an influence on film formation, its microstructure and density because of the ionized particles presence in the SDC vapor stream. Changes in crystallite size and surface morphology were determined from X-ray diffraction data and scanning electron microscopy images. Influence of bias voltage on porosity of formed SDC thin films on optical quartz were calculated from transmittance spectra data by using Swanepoel method. The porosity decreases up to 12% by decreasing bias voltage from 0 to ?150 V. 相似文献
20.