The present study aimed to design,develop,operate and evaluate a sightseeing spot recommendation system as a smart tourism tool that gathers and accumulates sightseeing spot information and considers personal preferen...The present study aimed to design,develop,operate and evaluate a sightseeing spot recommendation system as a smart tourism tool that gathers and accumulates sightseeing spot information and considers personal preferences as well as priority conditions to support tourism activities,especially in urban tourist areas.The system was developed by integrating web-geographic information systems(Web-GIS),the recommendation system and the evaluation system.Additionally,the system was operated for 4 weeks in the central part of Yokohama City in Kanagawa Prefecture,Japan,and the total number of users was 62.Based on the results of the web questionnaire survey,the system was highly useful for sightseeing activities,and further utilization of each function can be expected by continuing the operation.From the results of access analysis of users’log data,it is evident that the system has been used by different types of information terminals just as it was designed for,and that the system has been used according to the purpose of the present study,which is to support the sightseeing activities of users.However,the number of visits to pages related to the evaluation function of sightseeing spots and submitting function of new sightseeing spot information was low.This may improve if the system operation is conducted on a long-term basis.展开更多
The bits and power allocation model of adaptive power-rate mixture for multi-user multi-server power-line communication systems was analyzed with the restrictions of maximal total power,fixed rate for each real time (...The bits and power allocation model of adaptive power-rate mixture for multi-user multi-server power-line communication systems was analyzed with the restrictions of maximal total power,fixed rate for each real time (RT) user,minimal rate for each non-real time (NRT) user,maximal bits and power for each subcarrier in each orthogonal frequency division multiplexing (OFDM) symbol. An algorithm of resource dynamic allocation in the first OFDM symbol of each frame and resource optimal adjustment in the latter OFDM symbol of each frame was proposed. In the first OFDM symbol of every frame,resource is firstly assigned for RT users so as to minimize their total used power until satisfying their fixed rates; secondly the remainder resource of power and subcarriers are assigned for NRT users so as to minimize their total used power until satisfying their minimal rates also; lastly the remainder resource is again assigned for NRT users according to the proportional fairness strategy so as to maximize their total assigning rate. In the latter OFDM symbol of each frame,bits are swapped and power is adjusted for every user based on the resource allocation results of anterior OFDM symbol. The algorithm is tested in the typical power-line channel scenarios and the simulation results indicate that the proposed algorithm has better performances than the classical multi-user resource allocation algorithms and it realizes the multiple aims of multi-user multi-server resource allocation for power-line communication systems.展开更多
文摘The present study aimed to design,develop,operate and evaluate a sightseeing spot recommendation system as a smart tourism tool that gathers and accumulates sightseeing spot information and considers personal preferences as well as priority conditions to support tourism activities,especially in urban tourist areas.The system was developed by integrating web-geographic information systems(Web-GIS),the recommendation system and the evaluation system.Additionally,the system was operated for 4 weeks in the central part of Yokohama City in Kanagawa Prefecture,Japan,and the total number of users was 62.Based on the results of the web questionnaire survey,the system was highly useful for sightseeing activities,and further utilization of each function can be expected by continuing the operation.From the results of access analysis of users’log data,it is evident that the system has been used by different types of information terminals just as it was designed for,and that the system has been used according to the purpose of the present study,which is to support the sightseeing activities of users.However,the number of visits to pages related to the evaluation function of sightseeing spots and submitting function of new sightseeing spot information was low.This may improve if the system operation is conducted on a long-term basis.
基金Projects(51007021, 60402004) supported by the National Natural Science Foundation of China
文摘The bits and power allocation model of adaptive power-rate mixture for multi-user multi-server power-line communication systems was analyzed with the restrictions of maximal total power,fixed rate for each real time (RT) user,minimal rate for each non-real time (NRT) user,maximal bits and power for each subcarrier in each orthogonal frequency division multiplexing (OFDM) symbol. An algorithm of resource dynamic allocation in the first OFDM symbol of each frame and resource optimal adjustment in the latter OFDM symbol of each frame was proposed. In the first OFDM symbol of every frame,resource is firstly assigned for RT users so as to minimize their total used power until satisfying their fixed rates; secondly the remainder resource of power and subcarriers are assigned for NRT users so as to minimize their total used power until satisfying their minimal rates also; lastly the remainder resource is again assigned for NRT users according to the proportional fairness strategy so as to maximize their total assigning rate. In the latter OFDM symbol of each frame,bits are swapped and power is adjusted for every user based on the resource allocation results of anterior OFDM symbol. The algorithm is tested in the typical power-line channel scenarios and the simulation results indicate that the proposed algorithm has better performances than the classical multi-user resource allocation algorithms and it realizes the multiple aims of multi-user multi-server resource allocation for power-line communication systems.