Abstract: Systems and methods are disclosed for automatically performing motion correction in dynamic positron emission tomography scans, such as dynamic positron emission tomography myocardial perfusion imaging studies. An automated algorithm can be used. The algorithm can use simplex iterative optimization of a count-based cost-function customized to different dynamic phases for performing frame-by-frame motion correction.

Abstract: A method for managing threads and an electronic device using the method are provided. In the method, a current time is obtained. A time interval from now to a time for the processor to wake up next time is calculated. The processor is released until reaching the end of the time interval. When the end of the time interval is reached or a first notice signal of the processor is received, a first newest time is obtained to update a current time, and the current time is logged as a basis time. It is respectively checked whether the current time satisfies a plurality of predetermined time conditions of the registered threads against a plurality of registered threads in the threads. When the current time satisfies the predetermined time condition of a first registered thread among the registered threads, the first registered thread is waked up.

Abstract: An embodiment of the invention provides an orientation detection method for a portable device. The method comprises acquiring an accelerometer data, determining whether the portable device is in a flat status, determining whether the portable device is in a stable status, and when the portable device is determined in both the flat status and the stable status, stopping acquiring the accelerometer data until receiving an enable signal.

Abstract: A method for managing threads and an electronic device using the method are provided. In the method, a current time is obtained. A time interval from now to a time for the processor to wake up next time is calculated. The processor is released until reaching the end of the time interval. When the end of the time interval is reached or a first notice signal of the processor is received, a first newest time is obtained to update a current time, and the current time is logged as a basis time. It is respectively checked whether the current time satisfies a plurality of predetermined time conditions of the registered threads against a plurality of registered threads in the threads. When the current time satisfies the predetermined time condition of a first registered thread among the registered threads, the first registered thread is waked up.

Abstract: An embodiment of the invention provides an orientation detection method for a portable device. The method comprises acquiring an accelerometer data, determining whether the portable device is in a flat status, determining whether the portable device is in a stable status, and when the portable device is determined in both the flat status and the stable status, stopping acquiring the accelerometer data until receiving an enable signal.