Applied Mechanics and Materials Vols. 716-717

Abstract: In this paper, the basis function of TDCS system (Transform Domain Communication System) is used to design cognitive radar transmitter waveform. Based on the noise environment, the waveform can be adjusted adaptively. Then after clipping to reduce the PAPR (Peak to Average Power Ratio) of radar echo signal, the obtained signal is used as the next launch of the radar signal. The cognitive radar transmitter requires a nonlinear waveform to improve the efficiency of radar transmitter power amplifier, so reducing the PAPR of signal is essential. This paper presents the gray complementary sequence is applied to TDCS communication systems, and then it needs to reduce PAPR of signals by clipping. Proven, PAPR of the transmitted signal is maintained at about 3.25dB, and the signal has a low probability of intercept, high anti-interference ability and distant target detection range.

Abstract: Ocean bottom seismometers (OBS) are deployed at the interface of seawater and submarine medium for receiving the ship seismic wave signal. However, it’s difficult to extract the ship seismic wave information because of the complexity of seismic wave field source. In addition, the movement of the sea and coupling response can also lead to the same problem in the concerned frequency band. How to eliminate or reduce the external interference must be considered in the development of ocean bottom seismograph. This paper gives the basic principle of the sensor selection and structure design through the study of source characteristics and coupling theory. The improved ocean bottom seismometer can be matched with ship seismic wave signal and increase the detection distance.

Abstract: In this paper, the correlation between fused data and original data, the measured soil and the precipitation data over Huaihe river basin by exploring the inversion of soil moisture from the time and space based on the method of multi-source remote sensing data fusion has been studied. In order to fuse the AMSR-E data which is all-day and all-weather and can penetrate the earth surface to some extent, with the MODIS data that can reflect the surface condition and temperature characteristics, the method of wavelet fusion was carried out in MATLAB. The conclusions of this study are listed as follows: (1) the inversion result of the fused data based on AMSE-E and MODIS is much better than a single remote sensing data inversion; (2) the fused data based on AMSE-E and MODIS is sensitive to soil moisture change trend when the seasons alternated every year, especially in the spring, summer and autumn.

Abstract: It is important for modern agricultural production to measure temperature and humidity in a real time way. This paper combined the short-distance wireless communication technology ZigBee with the long-distance wireless communication technology GPRS to design a solar-powered temperature and humidity measuring system. The system is easy to install and can run in low cost, so it is especially suitable for small and medium agricultural producers.

Abstract: Gastrointestinal micro-bionic robot checkups system in clinical applications has very broad prospects and important significance, which has become one of the hot research fields of medical equipment at home and abroad. In this paper, based on the micro machining technology, micro actuation technology, microelectronics technology, wireless communication technology, wireless power transfer technology and clinical medical technology, this study focused on the system design and the locomotion compatibility of a miniature biomimetic robotic examination system for gastrointestinal tract. The aim is to provide a new effective approach and reference for the design of robotic endoscope system. The result shows that the miniature bionic creeping robotic system runs stably and has good move performance. This generation of miniature bionic creeping robotic system is very important for the further research. Development of the gastrointestinal tract considers running checkups micro-robots its efficacy and safety analysis of the compatibility of that robot and the human gastrointestinal tract.

Abstract: In order to make a more accurate control of temperature and humidity on the Closed Breeding Plant System (CBPS), air temperature and relative humidity changing with time and spatial distribution were monitored by temperature and humidity sensors in different space points (22) of CBPS for 6 consecutive days. The results showed that during the Bright Period , the average temperature of CBPS was 26.2 ± 0.5 °C, in the regulation of the target range and Relative humidity is 77 ± 2%, slightly higher than the control target. During Dark Period, the temperature falled from 26 °C to 19 °C and the average relative humidity reached 99%, significantly higher than control target. We could use the air switch to reduce relative humidity of CBPS.

Abstract: When detecting torque with surface acoustic wave (SAW) resonator sensors, the real strain of the host structure is not exactly consistent with the strain of SAW resonator due to material mismatch and the finite-thickness adhesive problem. A 3-layer (host structure, adhesive, and resonator layer) model is established. Finite-element Analysis (FEA) was used to investigate the strain transfer from the metal substrate to the SAW resonator (SAWR) through a bonding layer. The results show that the values of the strain transfer rate of FEA agree well with the experimental data. It can be concluded that FEA is of great value for SAW sensor design and sensing applications.

Abstract: Method to deal flight test data on take-off performance for light aircrafts was provided in this paper. Firstly, the corresponding flight test requirements of regulation CCAR23 and impact factors were analyzed. Then, subsection coefficient method, which divides take-off phrase into three sections with different mathematical model, was adopted and relevant characteristic parameters were developed by simplified these math model. Finally, the parameters which were identified and proved valuable by analyzing their feasibility were used to calculate the aircraft take-off performance, and main factors influencing take-off performance were provided. The data processing method on flight test is also applicable to analyze landing performance by constructing proper theoretical model.

Abstract: Mesoscale convective system (MCS) has a great influence on the air flight, this article used infrared cloud image data detected by FY2D static satellite, through TBB and area threshold found the MCS from cloud image, then calculated and analyzed the adjacent period of MCS’ cloud area ,centroid position, the development strength and some other characteristic changes to test whether it meet the targets matching principle, finally, discriminated whether the signed cloud were the same target cloud so as to realize the automatic tracking of MCS.

Abstract: The active power output of micrgrids is susceptible to external influences. When the load is high, the voltage of microgrids cannot be stabilized. Voltage fluctuation may cause the fan to stop working when the voltage is lower than the operating Voltage. The problem can be solved by applying SVG to the microgrid.