Một chiếc xe là chưa sử dụng trong một bãi đậu xe, và chủ sở hữu của chiếc xe được và đi một nơi nào đó. Trước khi được ra khỏi xe, ông quay về hệ thống báo động. Chủ sở hữu mang một điện thoại di động với anh ta, với các điện thoại kết nối với một hệ thống báo động không dây (WS) trong xe. WS có cảm biến phát hiện xem chiếc xe là cảm động bởi một ai đó. | 12 Mobile Services Computing 307 Scenario A car is parked in a parking lot and the owner of the car gets off and walks somewhere. Before he gets off the car he turns on the alarm system. The owner carries a cell phone with him with the phone connected to a wireless alarm system WAS in the car. WAS has sensors that detect whether the car is touched by someone. If the car is touched the WAS sends an alert to the owner s cell phone. Thereafter the owner sends a command to the WAS to protect his car from being stolen. Based on the thief s reaction different requests commands are sent to the WAS and the WAS gives feedbacks to the thief until the car engine is locked finally. The WAS works based on not only the owner s commands but also context information such as the time thief s attempt and resources available. The complete scenario of the WAS is shown in Fig. and is explained as follows A thief touches a car. The detector sensor of the car gets the information and sends it to the owner s cell phone. The owner of the car sends an alert invocation command to the WAS. The WAS gives a speech-based alert to the theft and the volume of the alert is determined by time if it is daytime the volume may be higher otherwise it is lower. The thief continues to tamper the car. The detector gets the information sends it to the owner s cell phone and prompts that the alert does not take effect. The owner sends a picture-taking alert command to the WAS. The WAS sends a speech-based alert that a picture will be taken if the theft continues. The thief still continues to tamper the car. The detector gets the information sends it to the owner s cell phone and prompts that the taking-picture alert did not take effect. The owner sends a picture-taking command to the WAS. The WAS invokes the corresponding service and a picture is taken of the thief and a speech alert is broadcast if the disk space is not enough to save the picture the resource manager is invoked and virtual .
