In seismic prospecting, fi eld conditions and other factors hamper the recording of the complete seismic wavefi eld; thus, data interpolation is critical in seismic data processing. Especially, in complex conditions, ...In seismic prospecting, fi eld conditions and other factors hamper the recording of the complete seismic wavefi eld; thus, data interpolation is critical in seismic data processing. Especially, in complex conditions, prestack missing data affect the subsequent highprecision data processing workfl ow. Compressive sensing is an effective strategy for seismic data interpolation by optimally representing the complex seismic wavefi eld and using fast and accurate iterative algorithms. The seislet transform is a sparse multiscale transform well suited for representing the seismic wavefield, as it can effectively compress seismic events. Furthermore, the Bregman iterative algorithm is an efficient algorithm for sparse representation in compressive sensing. Seismic data interpolation methods can be developed by combining seismic dynamic prediction, image transform, and compressive sensing. In this study, we link seismic data interpolation and constrained optimization. We selected the OC-seislet sparse transform to represent complex wavefields and used the Bregman iteration method to solve the hybrid norm inverse problem under the compressed sensing framework. In addition, we used an H-curve method to choose the threshold parameter in the Bregman iteration method. Thus, we achieved fast and accurate reconstruction of the seismic wavefi eld. Model and fi eld data tests demonstrate that the Bregman iteration method based on the H-curve norm in the sparse transform domain can effectively reconstruct missing complex wavefi eld data.展开更多
In this paper,a blind multiband spectrum sensing(BMSS)method requiring no knowledge of noise power,primary signal and wireless channel is proposed based on the K-means clustering(KMC).In this approach,the KMC algorith...In this paper,a blind multiband spectrum sensing(BMSS)method requiring no knowledge of noise power,primary signal and wireless channel is proposed based on the K-means clustering(KMC).In this approach,the KMC algorithm is used to identify the occupied subband set(OSS)and the idle subband set(ISS),and then the location and number information of the occupied channels are obtained according to the elements in the OSS.Compared with the classical BMSS methods based on the information theoretic criteria(ITC),the new method shows more excellent performance especially in the low signal-to-noise ratio(SNR)and the small sampling number scenarios,and more robust detection performance in noise uncertainty or unequal noise variance applications.Meanwhile,the new method performs more stablely than the ITC-based methods when the occupied subband number increases or the primary signals suffer multi-path fading.Simulation result verifies the effectiveness of the proposed method.展开更多
In order to improve the video quality of transmission with data loss,a spatial and temporal error concealment method was proposed,which considered both the state information of the network and the perceptual weight of...In order to improve the video quality of transmission with data loss,a spatial and temporal error concealment method was proposed,which considered both the state information of the network and the perceptual weight of the video content.The proposed method dynamically changed the reliability weight of the neighboring macroblock,which was used to conceal the lost macroblocks according to the packet loss rate of the current channel state.The perceptual weight map was utilized as side information to do weighted pixel interpolation and side-match based motion compensation for spatial and temporal error concealment,respectively.And the perceptual weight of the neighboring macroblocks was adaptively modified according to the perceptual weight of the lost macroblocks.Compared with the method used in H.264 joint model,experiment results show that the proposed method performs well both in subjective video quality and objective video quality,and increases the average peak signal-to-noise ratio(PSNR) of the whole frame by about 0.4 dB when the video bitstreams are transmitted with packets loss.展开更多
The current study represents an attempt at experiential value, perceived quality and customer satisfaction influence on customer lifetime value. The sampling frame consisted of Star Cruises purchases in Taiwan. The au...The current study represents an attempt at experiential value, perceived quality and customer satisfaction influence on customer lifetime value. The sampling frame consisted of Star Cruises purchases in Taiwan. The authors have collected yield 268 questionnaires, by screening out 13 questionnaires, including those missing value or incomplete answer, and finally a usable sample of 255 questionnaires were utilized in this study. The results show that experiential value, perceived quality and customer satisfaction have positive effects to customer lifetime value. Especially, experiential value has the strongest direct effect. Therefore, if resources are limited, the manager should focus on shaping the experiential value to increase customer lifetime value. Implications for marketing theory and practitioners are discussed, and possible directions for future research are sketched.展开更多
With the rapid development of Intemet technology, the traditional way of information transmission has undergone tremendous changes, especially in the lntemet environment. The spread of the online word of mouth as a pl...With the rapid development of Intemet technology, the traditional way of information transmission has undergone tremendous changes, especially in the lntemet environment. The spread of the online word of mouth as a platform for the Interact highlights its great influence and importance. Especially in the online shopping, these reflect the user's point of view and attitude of the online comment has been an unprecedented attention. Online reviews have become an important medium for consumers to understand their products before they buy goods, making them an important channel for potential consumers to understand the quality of goods and services. There are many studies on online reviews, but the research on the brand awareness of cruise ship companies is almost negligible. This paper provides a reference for the construction of cruise ship brand awareness system, and combines Nvivo software to analyze the online commentary system, and provides a reference for further research on cruise brand, and prospects for future research.展开更多
基金supported by the National Natural Science Foundation of China(Nos.41274119,41174080,and 41004041)the 863 Program of China(No.2012AA09A20103)
文摘In seismic prospecting, fi eld conditions and other factors hamper the recording of the complete seismic wavefi eld; thus, data interpolation is critical in seismic data processing. Especially, in complex conditions, prestack missing data affect the subsequent highprecision data processing workfl ow. Compressive sensing is an effective strategy for seismic data interpolation by optimally representing the complex seismic wavefi eld and using fast and accurate iterative algorithms. The seislet transform is a sparse multiscale transform well suited for representing the seismic wavefield, as it can effectively compress seismic events. Furthermore, the Bregman iterative algorithm is an efficient algorithm for sparse representation in compressive sensing. Seismic data interpolation methods can be developed by combining seismic dynamic prediction, image transform, and compressive sensing. In this study, we link seismic data interpolation and constrained optimization. We selected the OC-seislet sparse transform to represent complex wavefields and used the Bregman iteration method to solve the hybrid norm inverse problem under the compressed sensing framework. In addition, we used an H-curve method to choose the threshold parameter in the Bregman iteration method. Thus, we achieved fast and accurate reconstruction of the seismic wavefi eld. Model and fi eld data tests demonstrate that the Bregman iteration method based on the H-curve norm in the sparse transform domain can effectively reconstruct missing complex wavefi eld data.
基金Projects(61362018,61861019)supported by the National Natural Science Foundation of ChinaProject(1402041B)supported by the Jiangsu Province Postdoctoral Scientific Research Project,China+1 种基金Project(16A174)supported by the Scientific Research Fund of Hunan Provincial Education Department,ChinaProject([2016]283)supported by the Research Study and Innovative Experiment Project of College Students,China
文摘In this paper,a blind multiband spectrum sensing(BMSS)method requiring no knowledge of noise power,primary signal and wireless channel is proposed based on the K-means clustering(KMC).In this approach,the KMC algorithm is used to identify the occupied subband set(OSS)and the idle subband set(ISS),and then the location and number information of the occupied channels are obtained according to the elements in the OSS.Compared with the classical BMSS methods based on the information theoretic criteria(ITC),the new method shows more excellent performance especially in the low signal-to-noise ratio(SNR)and the small sampling number scenarios,and more robust detection performance in noise uncertainty or unequal noise variance applications.Meanwhile,the new method performs more stablely than the ITC-based methods when the occupied subband number increases or the primary signals suffer multi-path fading.Simulation result verifies the effectiveness of the proposed method.
基金Project(2006C11200) supported by the Science and Technology Project of Zhejiang Province of China
文摘In order to improve the video quality of transmission with data loss,a spatial and temporal error concealment method was proposed,which considered both the state information of the network and the perceptual weight of the video content.The proposed method dynamically changed the reliability weight of the neighboring macroblock,which was used to conceal the lost macroblocks according to the packet loss rate of the current channel state.The perceptual weight map was utilized as side information to do weighted pixel interpolation and side-match based motion compensation for spatial and temporal error concealment,respectively.And the perceptual weight of the neighboring macroblocks was adaptively modified according to the perceptual weight of the lost macroblocks.Compared with the method used in H.264 joint model,experiment results show that the proposed method performs well both in subjective video quality and objective video quality,and increases the average peak signal-to-noise ratio(PSNR) of the whole frame by about 0.4 dB when the video bitstreams are transmitted with packets loss.
文摘The current study represents an attempt at experiential value, perceived quality and customer satisfaction influence on customer lifetime value. The sampling frame consisted of Star Cruises purchases in Taiwan. The authors have collected yield 268 questionnaires, by screening out 13 questionnaires, including those missing value or incomplete answer, and finally a usable sample of 255 questionnaires were utilized in this study. The results show that experiential value, perceived quality and customer satisfaction have positive effects to customer lifetime value. Especially, experiential value has the strongest direct effect. Therefore, if resources are limited, the manager should focus on shaping the experiential value to increase customer lifetime value. Implications for marketing theory and practitioners are discussed, and possible directions for future research are sketched.
文摘With the rapid development of Intemet technology, the traditional way of information transmission has undergone tremendous changes, especially in the lntemet environment. The spread of the online word of mouth as a platform for the Interact highlights its great influence and importance. Especially in the online shopping, these reflect the user's point of view and attitude of the online comment has been an unprecedented attention. Online reviews have become an important medium for consumers to understand their products before they buy goods, making them an important channel for potential consumers to understand the quality of goods and services. There are many studies on online reviews, but the research on the brand awareness of cruise ship companies is almost negligible. This paper provides a reference for the construction of cruise ship brand awareness system, and combines Nvivo software to analyze the online commentary system, and provides a reference for further research on cruise brand, and prospects for future research.