情境分享系統可以讓同一群體的使用者在公共場所，感知自己與他人的位置與狀態。此篇研究的目的為希望透過低耗能藍牙與Web服務，在智慧型手機平台上，開發出一個易部署、易維護、易擴展的多人室內位置分享系統，使用者可以透過智慧型手機感知自己的位置，並且分享位置給系統中其他使用者。在室內定位上，使用低耗能藍牙的訊號強度來感知使用者的位置。在系統底層，使用RESTful API與 WebSocket API來串接服務；在操作介面方面，使用者有兩種操作介面，第一種為使用手機App定位與存取服務，第二種為使用瀏覽器執行Web應用程式來操作服務。雛型系統使用十個商用iBeacon標籤，實際布建在一個樓層，實測所得到的距離誤差值在3公尺到5公尺之間。

Location sharing system enables a group of members to share their locations with the others. In this work, we propose an indoor location-aware and sharing system based on Bluetooth Low Energy (BLE) and Web services. The objective of this study is to design and implement an easy-to-deploy, maintainable and scalable indoor location-aware and sharing system. The location-aware infrastructure of the proposed system is built with BLE beacons. We use the BLE sensors on the smartphones to compute proximity and judge the locations of users. Users can use both Web interface and mobile app to communicate and share their locations. In the deployed environment, ten commercial iBeacon sensors were used on a floor. The errors of the proximity values measured from the deployed iBeacon sensors fluctuate between three to five meters.

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