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Based on the premise that cross-selling exists in the items belonging to different species, a new algorithm for ISM is introduced in this paper. According to the relevance of two species, the cross-selling factor of species is def...
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Based on the premise that cross-selling exists in the items belonging to different species, a new algorithm for ISM is introduced in this paper. According to the relevance of two species, the cross-selling factor of species is defined in this paper. In the same way, the cross-selling factor of two items is described. With consideration of the direct profits and indirect profits brought by the marketing items, the calculation method for the items' overall profits and the species' overall profits are described in this paper. Experiments are conducted to show that the algorithms are effective and efficient.
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The use of active phased-array antenna in communication system can bring about not only improved system performance, but also extended functions, so it has found its ever-broadly applications in communication system. This paper in...
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The use of active phased-array antenna in communication system can bring about not only improved system performance, but also extended functions, so it has found its ever-broadly applications in communication system. This paper introduces an active phased-array antenna system that has eight antenna elements without RF phase shifters. The antenna system consists of planar array, digital T/R modules, receiving DBF; system control /analysis software, etc. Its basic theory is that in transmitting channel, the traditional RFphase shifter and attenuator are replaced by direct digital synthesizer (DDS). As the operating frequency of DDS available is not sufficiently high, the upper frequency converter is used to convert the frequency to required system operating frequency (2.0 GHz). In transmitting mode, through controlling DDS, the amplitude and phase weights needed for transmit beam formation and the LO signals needed for upper frequency conversion are produced. In receiving mode, through controlling DDS, the LO signals is needed for down frequency conversion for the received signal are produced. The resultant digital I/Q signals are used to form the receive beam. This paper introduces in detail the ways and results of an experiment on an active phased array antenna based on DDS. Through the research on the eight-element active phased array antenna based on DDS, the notable virtues of DDS technology in phased array antenna, and the potential applications of the phased array antenna in communications are proven.
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摘要 :
The use of active phased-array antenna in communication system can bring about not only improved system performance, but also extended functions, so it has found its ever-broadly applications in communication system. This paper in...
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The use of active phased-array antenna in communication system can bring about not only improved system performance, but also extended functions, so it has found its ever-broadly applications in communication system. This paper introduces an active phased-array antenna system that has eight antenna elements without RF phase shifters. The antenna system consists of planar array, digital T/R modules, receiving DBF; system control /analysis software, etc. Its basic theory is that in transmitting channel, the traditional RFphase shifter and attenuator are replaced by direct digital synthesizer (DDS). As the operating frequency of DDS available is not sufficiently high, the upper frequency converter is used to convert the frequency to required system operating frequency (2.0 GHz). In transmitting mode, through controlling DDS, the amplitude and phase weights needed for transmit beam formation and the LO signals needed for upper frequency conversion are produced. In receiving mode, through controlling DDS, the LO signals is needed for down frequency conversion for the received signal are produced. The resultant digital I/Q signals are used to form the receive beam. This paper introduces in detail the ways and results of an experiment on an active phased array antenna based on DDS. Through the research on the eight-element active phased array antenna based on DDS, the notable virtues of DDS technology in phased array antenna, and the potential applications of the phased array antenna in communications are proven.
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摘要 :
The use of active phased-array antenna in communication system can bring about not only improved system performance, but also extended functions, so it has found its ever-broadly applications in communication system. This paper in...
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The use of active phased-array antenna in communication system can bring about not only improved system performance, but also extended functions, so it has found its ever-broadly applications in communication system. This paper introduces an active phased-array antenna system that has eight antenna elements without RF phase shifters. The antenna system consists of planar array, digital T/R modules, receiving DBF; system control /analysis software, etc. Its basic theory is that in transmitting channel, the traditional RFphase shifter and attenuator are replaced by direct digital synthesizer (DDS). As the operating frequency of DDS available is not sufficiently high, the upper frequency converter is used to convert the frequency to required system operating frequency (2.0 GHz). In transmitting mode, through controlling DDS, the amplitude and phase weights needed for transmit beam formation and the LO signals needed for upper frequency conversion are produced. In receiving mode, through controlling DDS, the LO signals is needed for down frequency conversion for the received signal are produced. The resultant digital I/Q signals are used to form the receive beam. This paper introduces in detail the ways and results of an experiment on an active phased array antenna based on DDS. Through the research on the eight-element active phased array antenna based on DDS, the notable virtues of DDS technology in phased array antenna, and the potential applications of the phased array antenna in communications are proven.
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For space-borne P band Synthetic Aperture Radar (SAR) application, an airborne experimental circular&linear polarimetric SAR system is developed, this paper presents the instrument and airborne test result. Compared to linear polarization of P band, circular polarimetric SAR shows remarkable penetration efficacy in tropical jungle foliage covered region and subsurface targets detection. Besides, A new phenomenon of P band circular polarimetric SAR implies potential advantage in man-made linear object detection....
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For space-borne P band Synthetic Aperture Radar (SAR) application, an airborne experimental circular&linear polarimetric SAR system is developed, this paper presents the instrument and airborne test result. Compared to linear polarization of P band, circular polarimetric SAR shows remarkable penetration efficacy in tropical jungle foliage covered region and subsurface targets detection. Besides, A new phenomenon of P band circular polarimetric SAR implies potential advantage in man-made linear object detection.
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This paper proposed a new closed sequential pattern mining algorithm.The algorithm used a list of positional data to reserve the information of item ordering .By using these positional data, we developed two main pruning technique...
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This paper proposed a new closed sequential pattern mining algorithm.The algorithm used a list of positional data to reserve the information of item ordering .By using these positional data, we developed two main pruning techniques, backward super-pattern condition and same positional data condition. To ensure correct and compact resulted lattice, we also manipulated some special conditions. From the experimental results, our algorithm outperforms CloSpan in the cases of moderately large datasets and low support threshold.
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This paper proposed a new closed sequential pattern mining algorithm.The algorithm used a list of positional data to reserve the information of item ordering .By using these positional data, we developed two main pruning techn...
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This paper proposed a new closed sequential pattern mining algorithm.The algorithm used a list of positional data to reserve the information of item ordering .By using these positional data, we developed two main pruning techniques, backward super-pattern condition and same positional data condition. To ensure correct and compact resulted lattice, we also manipulated some special conditions. From the experimental results, our algorithm outperforms CloSpan in the cases of moderately large datasets and low support threshold.
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Since Huynen's original work, there have been many other proposed target decomposition theorems. In this paper, we provide a review of the different approaches used for target decomposition theory in radar polarimetry and classify...
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Since Huynen's original work, there have been many other proposed target decomposition theorems. In this paper, we provide a review of the different approaches used for target decomposition theory in radar polarimetry and classify three main types of theorems: those based on Mueller matrix, those using an eigenvector analysis of the coherency matrix, and those employing coherent decomposition of the scattering matrix. Support vector machine (SVM), as a novel approach in pattern recognition, has demonstrated a success in many fields. Here we first extract Scattering mechanisms of radar targets by target decomposition and color composite. Then we propose a new algorithm of target classification by combining target decomposition and support vector machine. We conduct the experiment on the polarimetric synthetic aperture radar data. Experimental results show that: it is feasible and efficient to target classification by designing SVM classifiers using target decomposition, and the effects of kernel functions and its parameters on the classification efficiency are significant.
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Retrodirective array (RDA) is a new type of array antenna with automatically backtracking function, which has special application value in radar countermeasures. When it is used to jam the linear frequency modulation (LFM) pulse c...
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Retrodirective array (RDA) is a new type of array antenna with automatically backtracking function, which has special application value in radar countermeasures. When it is used to jam the linear frequency modulation (LFM) pulse compression radar, the bandwidth of the backtracking signal is broadened by the jamming modulation, resulting in the beam pointing error. A model of repeater jamming using the phase conjugate array is established, and the influences on the beam pointing error of the bandwidth variety, the number of array element, the scanning angle and the leakage coefficient of the phase conjugate circuit are analyzed. The results show that the instantaneous frequency variety of the LFM signal has little effect on the beam pointing error, and the number of array element has a great influence on the beam pointing error. The more the number of array elements, the narrower the beam and the smaller the beam pointing error. With the scanning angle increasing, the beam pointing error is increasing. The variety of the leakage coefficient has a great influence on the sidelobe and gain of radiation pattern. Those results have important guiding significance for the use of RDA in radar countermeasures.
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For the retailing, the shelf space allocation is a key issue which impacts on the retailer's product sales and profits directly. For the small-scale supermarket, due to the small store and the product variety, the traditional 'for...
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For the retailing, the shelf space allocation is a key issue which impacts on the retailer's product sales and profits directly. For the small-scale supermarket, due to the small store and the product variety, the traditional 'format style' shelf space layout is not appropriate. To solve this problem, a shelf space allocation solution based on data mining techniques is proposed in this paper. With the introduction of association distance, we realize the description of the relevance between two any items purchased together in transaction database. With the concept of promotions coefficient, we get the description of the promotions ability of two items. Based on these concepts, with the cluster analysis techniques and the association rule mining technique, we propose a resolution based on 'island style', and get the optimization and automation of shelf space allocation in the small-scale supermarket.
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