Location technology is the key part of location based service. Different technologies have different accuracy, modifying to network and cost of operating. Also these technologies have limitation to network. This paper...Location technology is the key part of location based service. Different technologies have different accuracy, modifying to network and cost of operating. Also these technologies have limitation to network. This paper compares existing popular location technologies and gives some suggestions about choosing of location technologies in GSM and CDMA systems.展开更多
Location based services is promising due to its novel working style and contents. A software platform is proposed to provide application programs of typical location based services and support new applications develop...Location based services is promising due to its novel working style and contents. A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.展开更多
The location determination technology based on simple delay evaluations or GPS is not accurate enough or even impossible in urban and indoor environments due to the multi path propagation.To enhance the location accur...The location determination technology based on simple delay evaluations or GPS is not accurate enough or even impossible in urban and indoor environments due to the multi path propagation.To enhance the location accuracy and reduce the operation cost within these environments, this paper proposes a novel hybrid location determination technology which combines CELL ID with the database correlation method. The proposed method generate the prediction database of path loss according to CELL ID, and after the computation the smallest squared error of measured path loss and the prediction path loss, the location of the mobile terminal is decided by the coordinates of the best matching matrix entry.展开更多
Despite extensive research on R-trees, most of the proposed schemes have notbeen integrated into existing DBMS owing to the lack of protocols of concurrency control. R-linktree is an acceptable data structure to deal ...Despite extensive research on R-trees, most of the proposed schemes have notbeen integrated into existing DBMS owing to the lack of protocols of concurrency control. R-linktree is an acceptable data structure to deal with this issue, but problems like phantom still exist.In this paper, we focus on a conflict detection scheme based on R-link tree for completeconcurrency control. An in-memory operation control list is designed to suspend conflictingoperations . The main features of this approach are (1) it can be implemented easily and does notneed any extra information ; (2) No deadlocks are involved in locking scheme ; (3) Non-conflictingoperations are not restricted ; and (4) Phantom problems in R-link tree are avoided throughbeforehand predication . The experiment results show that this scheme is correct and gains bettersystem performance.展开更多
基金This work is supported by University IT Research Center ProjectKorea
文摘Location technology is the key part of location based service. Different technologies have different accuracy, modifying to network and cost of operating. Also these technologies have limitation to network. This paper compares existing popular location technologies and gives some suggestions about choosing of location technologies in GSM and CDMA systems.
基金This work is supported by Korea ITRC developing plan and Sino- Korea GIS center
文摘Location based services is promising due to its novel working style and contents. A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.
基金This research was supported by University IT Research Center ProjectKorea
文摘The location determination technology based on simple delay evaluations or GPS is not accurate enough or even impossible in urban and indoor environments due to the multi path propagation.To enhance the location accuracy and reduce the operation cost within these environments, this paper proposes a novel hybrid location determination technology which combines CELL ID with the database correlation method. The proposed method generate the prediction database of path loss according to CELL ID, and after the computation the smallest squared error of measured path loss and the prediction path loss, the location of the mobile terminal is decided by the coordinates of the best matching matrix entry.
文摘Despite extensive research on R-trees, most of the proposed schemes have notbeen integrated into existing DBMS owing to the lack of protocols of concurrency control. R-linktree is an acceptable data structure to deal with this issue, but problems like phantom still exist.In this paper, we focus on a conflict detection scheme based on R-link tree for completeconcurrency control. An in-memory operation control list is designed to suspend conflictingoperations . The main features of this approach are (1) it can be implemented easily and does notneed any extra information ; (2) No deadlocks are involved in locking scheme ; (3) Non-conflictingoperations are not restricted ; and (4) Phantom problems in R-link tree are avoided throughbeforehand predication . The experiment results show that this scheme is correct and gains bettersystem performance.
