https://blog.wongcw.com/2018/12/04/ibm%e5%bb%ba%e7%ab%8b%e5%9f%ba%e6%96%bc%e4%bd%8e%e5%8a%9f%e8%80%97%e8%97%8d%e7%89%99%e4%bf%a1%e6%a8%99%e7%9a%84%e5%ae%a4%e5%85%a7%e5%ae%9a%e4%bd%8d%e7%b3%bb%e7%b5%b1/
IBM建立基於低功耗藍牙信標的室內定位系統