According to the measurement requirements of leakage current from the national standards such as Standard GB9706.1-2007, this article describes the existing problems of isolated power earthing during leakage current measurement. Aiming at improving the measurement accuracy and protecting the security of testing engineers, we analyses several methods for isolated power earthing during the leakage current measurement, and various reasons of possible differences among test values of leakage current. Based on the existing national standards, this article proposes alternative testing methods for discussion.
Electric Power Supplies ; Equipment Safety

The source impedance of the power circuit in the x-ray machine is analyzed in the paper and based on the voltage drop generated by the impedance, the cross-sectional area of the cable is calculated. In the end, the cross-sectional areas of the cables, corresponding to their respective distances between the transformers and the switchboards are given.
Electric Power Supplies ; Radiography ; instrumentation

OBJECTIVE: To explore the optimization scheme of maintaining bus voltage stability during turbo-turbine acceleration and deceleration of ventilator. METHODS: The ideal diode is used to replace the diode in the busbar power supply circuit, and a comparative discharge circuit is added to the busbar. When the busbar voltage is higher than the preset threshold, the comparator can be opened and the energy could be discharged through the power resistor. RESULTS: When the turbine starts and stops rapidly, the optimized scheme can effectively reduce the bus impedance, and the discharge circuit can maintain the bus voltage fluctuation less than 2 V. CONCLUSIONS The optimization scheme proposed in this study can effectively improve the efficiency and stability of the turbine in the process of acceleration and braking, and provide reference for the design of the stability maintenance circuit of the ventilator turbine bus.
Electric Power Supplies ; Ventilators, Mechanical

Nanogenerator (triboelectric nanogenerator and piezoelectric nanogenerator) has experienced a rapid development since it was proposed. This technique can covert various mechanical energies into electric energy, including human motion energy, wind energy, acoustic energy and ocean energy. The converted electricity can be used for health monitoring and physiological function regulation, such as pulse detection, bioelectrical stimulation and cardiac pacing. This review summarizes the structure, working mechanism, output performance of nanogenerator and its latest progress in circulatory system, nervous system, biological tissue, sleep and rescue system. Additionally, a further analysis was also made on the application challenge of nanogenerator in clinical treatment. In the future, nanogenerator is expected to be an auxiliary power source, or even to replace battery to power medical electronic device and realize the self-powered health monitoring and physiological function regulation of human body.
Electric Power Supplies ; Electricity ; Humans

In recent years active implantable medical devices(AIMD) are being developed rapidly. Many battery systems have been developed for different AIMD applications. These batteries have the same requirements which include high safety, reliability, energy density and long service life, discharge indication. History, present and future of batteries used in AIMD are introduced in the article.
Electric Power Supplies ; Prostheses and Implants

This study aims to analyze and improve Howland current source circuit and to study the constant current source of alternating current with high output impedance and high stability. A simulation study was carried out on the constant-current characteristics of Howland current source from two aspects of resistance match value and the selection of Op amp parameters, and then the output impedance was analyzed. The simulation experiment showed that when it was with the best matched resistance, the constant-current characteristics of Howland current source was better. Op amp parameters could affect the constant-current characteristics of Howland current source. In Howland current source circuit, the current source after parameter optimization had better output impedance and load capacity. The results showed that there was the best matched resistance in the selection by Howland current source. The Op amp with large broadband, high slew rate and open loop gain, and wide range of power supply voltage is more suitable for the bioelectrical impedance detection circuit.
Electric Impedance ; Electric Power Supplies ; Electricity

The anatomy of the voice is not limited to the region of the larynx. Practically all body systems affect the voice. The larynx receives the greatest attention because it is the most sensitive and expressive component of the vocal mechanism, but anatomic interactions throughout the singer's body must be considered in making the singing voice. The physiology of voice production is exceedingly complex. The voice requires interactions among the power source, the oscillator, and the resonator. The review of functional anatomy and physiology in vocal technique would provide information on the terminology, components, and workings of the voice to permit an understanding of practical, every clinical problems and their solutions. The otolaryngologist, speech language pathologist, singing or acting teacher, singer, and actor would have benefit greatly from more extensive study of voice science.
Electric Power Supplies ; Larynx ; Physiology* ; Singing ; Voice

Investigation and analysis of accidents are critical elements of safety management. The over-riding purpose of an organization in carrying out an accident investigation is to prevent similar accidents, as well as seek a general improvement in the management of health and safety. Hundreds of workers have suffered injuries while installing, maintaining, or servicing machinery and equipment due to sudden re-energization of power lines. This study presents and analyzes two electrical accidents (1 fatal injury and 1 serious injury) that occurred because the power supply was reconnected inadvertently or by mistake.
Electric Power Supplies ; Greece* ; Safety Management

This study introduced a time-delay exposure system independent of the mobile digital radiography equipment. The system consisted of lithium battery, delay control circuit, micro electric motor and related auxiliary facilities. When the starting time was reached through the delay circuit, the motor pushed out the rod to squeeze the exposure button and completed the exposure. The accessories used in this system were easy to purchase and cheap. At the same time, the technology was mature and had good compatibility. The exposure success rate was high and the exposure effect was satisfactory. This time-delay exposure system had good practicability and popularization value.
Radiographic Image Enhancement ; Technology ; Electric Power Supplies

Macaque is a common animal model in drug safety assessment. Its behavior reflects its health condition before and after drug administration, which can effectively reveal the side effects of drugs. At present, researchers usually rely on artificial methods to observe the behavior of macaque, which cannot achieve uninterrupted 24-hour monitoring. Therefore, it is urgent to develop a system to realize 24-hour observation and recognition of macaque behavior. In order to solve this problem, this paper constructs a video dataset containing nine kinds of macaque behaviors (MBVD-9), and proposes a network called Transformer-augmented SlowFast for macaque behavior recognition (TAS-MBR) based on this dataset. Specifically, the TAS-MBR network converts the red, green and blue (RGB) color mode frame input by its fast branches into residual frames on the basis of SlowFast network and introduces the Transformer module after the convolution operation to obtain sports information more effectively. The results show that the average classification accuracy of TAS-MBR network for macaque behavior is 94.53%, which is significantly improved compared with the original SlowFast network, proving the effectiveness and superiority of the proposed method in macaque behavior recognition. This work provides a new idea for the continuous observation and recognition of the behavior of macaque, and lays the technical foundation for the calculation of monkey behaviors before and after medication in drug safety evaluation.
Animals ; Electric Power Supplies ; Macaca ; Recognition, Psychology