Why am I frequently getting disconnected from wifi after some time of use?

Question

I use a Lenovo g50-45 with Realtek Semiconductor Co., Ltd. RTL8723BE PCIe Wireless Network Adapter. I am connected to the wifi and can access the Internet for like 10-5 min and then the wifi will still be connected but there will be no Internet. Here are some details and analysis report's wireless-info.txt