Abstract: The present invention relates to a digital portable pulse oximeter and battery-powered control method thereof. The automatic switching of the power supply is achieved by adding a Hall circuit, and the data displayed is allowed to always face the users by adding an acceleration sensor to the circuit. The advantageous effects of the present invention compared with the prior art are: Users can always read the data from the front side no matter which way they move. The digital portable pulse oximeter of the present invention can be automatically turned on just by inserting a finger, without having to press the switch button, and cut off the power supply by pulling out the finger, as well as judge intelligently whether to continue the measurement after the finger has been pulled out. If yes, the power supply will stay on, which reduces the energy waste and low efficiency caused by the restarting program initialization, improves the use efficiency of the battery and prolongs the battery life.

Abstract: A digital pulse oximeter with automatic orientation change function, comprising a housing that is configured to clamp a human finger being tested, a display window disposed at outside of and atop the housing, a circuit being disposed within the housing for calculating and analyzing the tested signals, and displaying them in the display window atop the housing via a display, wherein the said circuit has only one control key disposed on the housing, the said circuit allowing the display contents of the display to be always oriented properly for easy reading by connecting with one two-axis or three-axis accelerometer. The digital pulse oximeter of the present invention is featured with small size and convenient operation and can shift from one function to another using only one control key in conjunction with the interface display, thereby increasing the functions of small-sized pulse oximeters.

Abstract: The present invention relates to a networked differential protection method for a distribution network based on overhauling of terminal equipment. The present invention comprises the steps of detecting in real time an operation state of a terminal equipment, and reconstructing a differential logic when there is a terminal equipment under an overhaul state so as to bring it into a state in which an overhaul mode and an operation mode are in parallel; for the operation mode in the state in which an overhaul mode and an operation mode are in parallel, only calculating data of all nodes in normal operation in an electrical element by a differential protection for the electrical element, while excluding data under the overhaul state in the electrical element from taking part in calculation. With the method of the present invention, the operation switch may be reliably switched off and failures may be isolated when they appear during an experiment of a scheduled test.