Please select the most similar patent number from A, B, C and D. Which number is?
An ultrasonic rainfall measurement system capable of automatic triggering and self-calibration. Said system comprises a rainfall monitoring module, a self-calibration and rainfall amount measurement module, a central processing module, a water level monitoring module and a drainage module, wherein the rainfall monitoring module is configured to monitor rainfall and send a rainfall signal; the self-calibration and rainfall amount measurement module is configured to emit, under the control of the central processing module, an ultrasonic signal and receive a signal, so as to obtain a calibration flight time, and is configured to emit, under the control of the central processing module, an ultrasonic signal to an accumulated water surface in a rainfall gauge and receive a measurement echo signal reflected by the accumulated water surface, so as to obtain a measurement flight time; the central processing module is configured to receive the rainfall signal, start the water level monitoring module and the self-calibration and rainfall amount measurement module, and is configured to calculate a rainfall amount value and output same in a fixed format; the water level monitoring module is configured to monitor the water level in the rainfall gauge and send a drainage signal; and the drainage module is configured to receive the drainage signal, and open a drainage valve to drain accumulated water in the rainfall gauge.
A: A rainfall and water vapor comprehensive measurement device and method based on a dual-frequency dual-polarization microwave link, comprising a dual-frequency transmitter, a dual-frequency receiver, a dual-polarization antenna, a data collector, and a data processing terminal. The dual-frequency transmitter is combined with the dual-polarization antenna to alternately transmit microwave signals, the dual-frequency receiver is combined with the dual-polarization antenna to synchronously receive the microwave signals with corresponding frequencies and polarization modes, and the data collector collects the microwave signals in real time and transmits the microwave signals to the data processing terminal. The method comprises: first distinguishing sunny and rainy periods, performing water vapor information inversion in the sunny period, and performing rainfall information inversion in the rainy period; and calculating attenuation caused by rainfall or attenuation caused by water vapor by utilizing the determined reference level value, and determining rainfall intensity or water vapor density according to a corresponding empirical relationship. On the basis of double-frequency determination of the sunny and rainy days, water vapor density inversion is carried out in sunny days, and rainfall intensity inversion is carried out in rainy days. More importantly, the benefit of obtaining atmospheric information by the microwave link attenuation effect is fully exerted.
B: A multi-focus ultrasonic wave generation device and generation method. The generation device comprises an ultrasonic excitation module (1), a control module (2), a monitoring module (3) and a feedback module (4). The ultrasonic excitation module (1) comprises a plurality of ultrasonic transducers (11); the control module (2) is used to respectively control, according to ultrasonic parameters of a plurality of objective targets, the plurality of ultrasonic transducers (11) to emit ultrasonic pulse signals to the plurality of objective targets; the monitoring module (3) is used to detect whether the ultrasonic pulse signals emitted by the ultrasonic transducers (11) are focused on the objective targets; the feedback module (4) is used to send a feedback signal to the control module (2) when the ultrasonic pulse signals emitted by the ultrasonic transducers (11) are not focused on the objective targets; and the control module (2) adjusts the positions of the ultrasonic transducers (11) according to the feedback signal, so that the ultrasonic pulse signals emitted by the ultrasonic transducers (11) are focused on the objective targets. The multi-focus ultrasonic wave generation device can dynamically and accurately stimulate a plurality of objective targets in real time as required.
C: A polysomnography-based system and method for monitoring sleep of a pneumonia patient. The system comprises a central processing module. The central processing module is electrically connected, via wires, to a display module, a sleep monitoring module, a breathing monitoring module, a heart monitoring module, a body position monitoring module, a data transmission module, a power supply module, and a fault monitoring and alert module. The fault monitoring and alert module is electrically connected to the display module via a wire. The system and method achieve remote data transmission and allow various data to be processed and transmitted in a centralized manner, thus enabling technicians to keep a record or make a diagnosis conveniently, while enabling detection of faults in the system to reduce data measurement errors and ensure data accuracy.
D: A preoperative beam dose measurement device, comprising a device casing (1), an optical conversion module (2), a reflection transmission module (3) and a signal detection module (4), wherein the optical conversion module (2), the reflection transmission module (3) and the signal detection module (4) are all mounted on the device casing (1); the optical conversion module (2) is used for receiving an externally transmitted beam signal, converting the beam signal into an optical signal and transmitting the optical signal to the reflection transmission module (3); the reflection transmission module (3) is used for transmitting the received optical signal to the signal detection module (4); and the signal detection module (4) is used for obtaining an optical signal distribution map according to the received optical signal and transmitting the optical signal distribution map to an image analysis system so as to obtain beam dose distribution by means of the image analysis system. The preoperative beam dose measurement device has a fast reaction speed, a high measurement precision and a small size. A computer can directly convert image data into dose data in real time due to advanced calibration of the preoperative beam dose measurement device.
Answer: A