Effect of plunger number on hydraulic transformer's flow pulsation rate

In order to supply theoretical guidance to hydraulic transformer's design and application,the effect of the number of plungers in hydraulic transformer on its flow characteristic is analyzed,theoretical analysis and simulation are done on hydraulic transformer's flow characteristic when the number of plungers is different.Based on the working principle of swash plate piston hydraulic components,mathematical models of instantaneous flow and flow pulsation rate are built,and simulation study is done with MATLAB.As a result,the effect is found,and some conclusions worth referring to are obtained.

Cynodon dactylon andSida acuta extracts impact on the function of the cardiovascular system in zebrafish embryos

The aim of the present study was to screen cardioactive herbs from Western Ghats of India. The heart beat rate （HBR） and blood flow during systole and diastole were tested in zebrafish embryos. We found that Cynodon dactylon （C. dactylon） induced increases in the HBR in zebrafish embryos with a HBR of （3.968±0.344） beats/ s, which was significantly higher than that caused by betamethosone [（3.770±0.344） beats/s]. The EC50 value of C. dactylon was 3.738 μg/mL. The methanolic extract of Sida acuta （S. acuta） led to decreases in the HBR in zebrafish embryos [（1.877 ±0.079） beats/s], which was greater than that caused by nebivolol （positive control）. The EC50 value of Sida acuta was 1.195 μg/mL. The untreated embryos had a HBR of （2.685±0.160） beats/s at 3 d post fertilization （dpf）. The velocities of blood flow during the cardiac cycle were （2,291.667 ±72.169） μm/s for the control, （4,250± 125.000） μm/s for C. dactylon and （1,083.333±72.169） μm/s for S. acuta. The LC50 values were 32.6 μg/mL for C. dactylon and 20.9 μg/mL for S. acuta. In addition, the extracts exhibited no chemical genetic effects in the drug dosage range tested. In conclusion, we developed an assay that can measure changes in cardiac function in response to herbal small molecules and determine the cardiogenic effects by microvideography.

Performance Analysis of 32-User Spectral Phase Encoding Time Domain System for Fiber-Optic CDMA Networks

Multiple access techniques are required to meet the demand for high-speed and large-capacity commtmications in optical networks, which allow multiple users to share the fiber bandwidth. O-CDMA （optical code-division multiple-access） is receiving increased attention due to its potential apphcations for LAN optical networks. O-CDMA is attractive for next generation broadband access networks due to its features of allowing fully asynchronous transmission with low latency access, soft capacity on demand, protocol transparency, simplified network management as well as increased flexibility of QoS （Quality of Service） control and enhanced confidentiahty in the network. Hence, the authors experimentally investigate an ultra short pulse O-CDMA scheme based on spectral phase encoding and decoding of coherent mode-locked laser pulses, they proposed a technique using spectral phase encoding time domain system for 32 users. This technique is proved to be much effective to handle 32 users at 4 Gb/s bit rate and 60 km SMF （single mode fiber） transmission used for SPE O-CDMA system. Results indicate significant improvement in term low BER （beat error rate） and very high quality factor in the form of QoS. The authors have used PSO （pseudo orthogonal） codes and random phase code. The simulations are carried out using OptSim （RSOFT）.