Packet contention is a key issue in optical packet switch (OPS) networks and finds a viable solution by including optical buffering techniques incorporating fiber delay lines (FDLs) in the switch architecture. The pre...Packet contention is a key issue in optical packet switch (OPS) networks and finds a viable solution by including optical buffering techniques incorporating fiber delay lines (FDLs) in the switch architecture. The present paper proposes a novel switch architecture for packet contention resolution in synchronous OPS network employing the packet circulation in FDLs in a synchronized manner. A mathematical model for the proposed switch architecture is developed employing packet queuing control to estimate the blocking probability for the incoming traffic. The switch performance is analyzed with a suitable contention resolution al-gorithm through the computer simulation. The simulation results substantiate the proposed model for the switch architecture.展开更多
A surface soil moisture model with improved spatial resolution was developed using remotely sensed apparent thermal inertia(ATI).The model integrates the surface temperature derived from TM/ETM+ image and the mean ...A surface soil moisture model with improved spatial resolution was developed using remotely sensed apparent thermal inertia(ATI).The model integrates the surface temperature derived from TM/ETM+ image and the mean surface temperature from MODIS images to improve the spatial resolution of soil temperature difference based on the heat conduction equation,which is necessary to calculate the ATI.Consequently,the spatial resolution of ATI and SMC can be enhanced from 1 km to 120 m(TM) or 60m(ETM+).Moreover,the enhanced ATI has a much stronger correlation coefficient(R^2) with SMC(0.789) than the surface reflectance(0.108) or the ATI derived only from MODIS images(0.264).Based on the regression statistics of the field SMC measurement and enhanced ATI,a linear regression model with an RMS error of 1.90%was found.展开更多
In this research, a content-based image retrieval (CBIR) system for high resolution satellite images has been developed by using texture features. The proposed approach uses the local binary pattern (LBP) texture ...In this research, a content-based image retrieval (CBIR) system for high resolution satellite images has been developed by using texture features. The proposed approach uses the local binary pattern (LBP) texture feature and a block based scheme. The query and database images are divided into equally sized blocks, from which LBP histograms are extracted. The block histograms are then compared by using the Chi-square distance. Experimental results show that the LBP representation provides a powerful tool for high resolution satellite images (HRSI) retrieval.展开更多
This paper studies the tree based contention resolution algorithm over a random multi access channel, and proposes a new algorithm model which is named Improved Ternary tree Algorithm( ITA ). The channel throughp...This paper studies the tree based contention resolution algorithm over a random multi access channel, and proposes a new algorithm model which is named Improved Ternary tree Algorithm( ITA ). The channel throughput over blocked access reaches 0 422. The analytical expression and computer simulation results indicate that the performance of ITA is better than the basic binary and ternary tree algorithm.展开更多
文摘Packet contention is a key issue in optical packet switch (OPS) networks and finds a viable solution by including optical buffering techniques incorporating fiber delay lines (FDLs) in the switch architecture. The present paper proposes a novel switch architecture for packet contention resolution in synchronous OPS network employing the packet circulation in FDLs in a synchronized manner. A mathematical model for the proposed switch architecture is developed employing packet queuing control to estimate the blocking probability for the incoming traffic. The switch performance is analyzed with a suitable contention resolution al-gorithm through the computer simulation. The simulation results substantiate the proposed model for the switch architecture.
基金Project (2013CB227904) supported by the National Basic Research Program of ChinaProject (2012QNB09) supported by the Fundamental Research Funds for the Central University,ChinaProject (NCET-12-0956) supported by the Program for New Century Excellent Talents
文摘A surface soil moisture model with improved spatial resolution was developed using remotely sensed apparent thermal inertia(ATI).The model integrates the surface temperature derived from TM/ETM+ image and the mean surface temperature from MODIS images to improve the spatial resolution of soil temperature difference based on the heat conduction equation,which is necessary to calculate the ATI.Consequently,the spatial resolution of ATI and SMC can be enhanced from 1 km to 120 m(TM) or 60m(ETM+).Moreover,the enhanced ATI has a much stronger correlation coefficient(R^2) with SMC(0.789) than the surface reflectance(0.108) or the ATI derived only from MODIS images(0.264).Based on the regression statistics of the field SMC measurement and enhanced ATI,a linear regression model with an RMS error of 1.90%was found.
文摘In this research, a content-based image retrieval (CBIR) system for high resolution satellite images has been developed by using texture features. The proposed approach uses the local binary pattern (LBP) texture feature and a block based scheme. The query and database images are divided into equally sized blocks, from which LBP histograms are extracted. The block histograms are then compared by using the Chi-square distance. Experimental results show that the LBP representation provides a powerful tool for high resolution satellite images (HRSI) retrieval.
文摘This paper studies the tree based contention resolution algorithm over a random multi access channel, and proposes a new algorithm model which is named Improved Ternary tree Algorithm( ITA ). The channel throughput over blocked access reaches 0 422. The analytical expression and computer simulation results indicate that the performance of ITA is better than the basic binary and ternary tree algorithm.
基金Supported by the National Basic Research Program of China under Grant No.2003CB317003(国家重点基础研究发展计划(973))Me Strategy Grant of City University of Hong Kong of China under Grant Nos.70017097001777(香港城市大学战略发展计划)
基金The Young Junior Faculties Programme of Education Department of Henan Province(No.2011GGJS-081)the Project in Natural Science Research Foundation of Education Department of Henan Province(No.2010A510002)