Real-Time Synchronous Integration of Radar and Raingauge Measurements Based on the Quasi Same-Rain-Volume Sampling

A technique for real-time synchronous integration of radar and raingauge measurements based on the concept of the quasi same-rain-volume sampling（QSVS） is presented.Because of the temporal and spatial discrepancies and resolution differences,the integration of radar measurements with raingauge observations has long been a difficult task.Observations indicate that there exists a correlation that conforms to the power law between hourly accumulated raingauge measurement（Q_G） and detected radar echo（Z_（OH）） over the raingauge.On the basis of this,a concept of the QSVS and five direct correspondent formulas of radar and raingauge samples are built up,aiming to eliminate the temporal and spatial discrepancies.A convenient and practical sampling method—the time integral vertical synchronous sampling（TIVS） is proposed and the Z_（OH）—Q_G relationship is studied.It is significant that under the fixed exponent,the coefficient A_B or A_M varies flexibly in accordance with the temporal and spatial variability of natural precipitation,having the function of synchronously integrating the Z—R conversion and the gauge adjustment into a single equation,and thus the precipitation estimation errors caused by detecting resolution differences between radar and raingauge can be obviously mitigated.The real-time synchronous integration technique using the Z_（OH）—Q_G relationship to estimate the ground hourly rainfall accumulation is called the radar-gauge synchronous integration method（RASIM）.The experiments of two cases show that the accuracy of estimated surface hourly rainfall accumulation within 230 km is about 90%,and the average relative error for the point estimation over the whole process is about 20%. Through the detailed analysis of the applicability of TIVS in three environmental fields with various wind drifts,the physical essence of TIVS is explored：it is an approximate QSVS.By analyzing the data pairs of radar and raingauge,an effective quality-control procedure is established,which can greatly improve the stability and rationarity of the Z_（OH）—Q_G relationship.The forecasting product of hourly rainfall accumulation derived from the RASIM has been put into operation.It is demonstrated that the RASIM plays an important role in the quantitative monitoring and forecasting of short-term torrential rainfall.

Double Position Servo Synchronous Drive System Based on Cross-Coupling Integrated Feedforward Control for Broacher

Synchronization errors directly deteriorate the machining accuracy of metal parts and the existed method cannot keep high synchronization precision because of external disturbances. A new double position servo synchronous driving scheme based on semi-closed-loop cross- coupling integrated feedforward control is proposed. The scheme comprises a position error cross-coupling feedfor-ward control and a load torque identification with feed- forward control. A digital integrated simulation system for the dual servo synchronous drive system is established. Using a 20 t servo broacher, performance analysis of the scheme is conducted based on this simulation system and the simulation results show that systems with traditional parallel or single control have problems when the work- table works with an unbalanced load. However, the system with proposed scheme shows good synchronous perfor- mance and positional accuracy. Broaching tests are performed and the experimental results show that the maximum dual axis synchronization error of the system is only 8μm during acceleration and deceleration processes and the error between the actual running position and the given position is almost zero. A double position servo synchronous driving scheme is presented based on crosscoupled integrated feedforward compensation control, which can improve the synchronization precision.

A Low Power Non-Volatile LR-WPAN Baseband Processor with Wake-Up Identification Receiver

The paper proposes a low power non-volatile baseband processor with wake-up identification(WUI) receiver for LR-WPAN transceiver.It consists of WUI receiver,main receiver,transmitter,non-volatile memory(NVM) and power management module.The main receiver adopts a unified simplified synchronization method and channel codec with proactive Reed-Solomon Bypass technique,which increases the robustness and energy efficiency of receiver.The WUI receiver specifies the communication node and wakes up the transceiver to reduce average power consumption of the transceiver.The embedded NVM can backup/restore the states information of processor that avoids the loss of the state information caused by power failure and reduces the unnecessary power of repetitive computation when the processor is waked up from power down mode.The baseband processor is designed and verified on a FPGA board.The simulated power consumption of processor is 5.1uW for transmitting and 28.2μW for receiving.The WUI receiver technique reduces the average power consumption of transceiver remarkably.If the transceiver operates 30 seconds in every 15 minutes,the average power consumption of the transceiver can be reduced by two orders of magnitude.The NVM avoids the loss of the state information caused by power failure and energy waste caused by repetitive computation.