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Spinel Li4-xKxTi5O12(x=0, 0.03) were successfully synthesized by a traditional solid-state method and systematically investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and the charge-discharge test, respectively. The results demonstrated that Li3.97K0.03Ti5O12exhibited much better rate performance in comparsion with Li4Ti5O12. At 0.2 C and 10 C, it delivered a discharge capacity of 173 mAh g-1and 124 mAh g-1respectively, and after 100 cycles at 10 C, 96.1% of its initial capacity was retained.

Chengdao area is a multiple hydrocarbon accumulation belt with the typical tectonic background, and its main target stratum is Neogene. However, the exploration and recognition level of Minghuazhen Formation is still at the primary stage. Based on the comprehensive analysis of seismic, well-logging, logging and geochemical data, and combined with its structural characteristics, intensity of fault activity and reservoir-caprock assemblage, this paper systematically analyzed the dominant factors of hydrocarbon accumulation in Minghuazhen Formation, and clarified that the tectonic setting controlled where the hydrocarbon enriched, intensity of fault activity influenced how much of hydrocarbon enriched and the reservoir-seal assemblage dominated hydrocarbon accumulation strata. Then two types of hydrocarbon accumulation models, that is, main fault-sand body and main fault-secondary fault–sand body were established.

Based on the fault activity, geochemical data and predecessor research results on tectonic subsidence and source rock of Bohai Sea Area, this paper took Bohai Sea Area as an example to compare its structural activity factors with its source rock indexes, and then to explore fault activity’s controlling effect on source rock. And the results shows: source rock thickness is mainly controlled by fault throw of boundary fault, but it is also be influenced by others factors in different stages; Fault activity rate, climatic conditions etc. factors are all key factors influencing organic matter percentage in source rock. And the key factors may change in different stages; Present organic matter maturities in different source rock are controlled by their present tectonic subsidence. And the bigger the tectonic subsidence, the higher the maturity; Source rock qualities on different structural belts are influenced by their distances away from the boundary fault, and the closer, the better. But quality on central uplift belt is worse than that on sub-sag belt flank.

A texture feature extraction method based on Gabor wavelet transform is presented to avoid the limitations of the shape structure characteristics extraction in the palm vein image. First acquire the palm vein images by independent structures of vein acquire device then extracts ROI area of vein images by determining the centerline of the middle finger and ring finger interphalangeal. Correcting the vein image by Gamma operator will improve the contrast of the processing image. Finally, transform the image based on Gabor wavelet to extract texture feature.

Phase unwrapping (PU) is a difficult task commonly found in applications involving interferometric synthetic aperture radar (InSAR), magnetic resonance imaging (MRI) and optical surface profile measurements; all of which involve mathematically ill-posed problems. Conventional algorithms exhibit strong shortcomings in PU when phase discontinuity flaws exist. To simulate these situations, we are custom-designed test data with a phase discontinuity flaw. This simulated data is a 3D Gaussian distribution with an arc-shaped notch as a phase flaw. PU is carried out by Bayesian inference and MRF (Markov Random Field) modeling. A graph cut algorithm is employed for optimization with respect to energy minimization. Three other conventional algorithms are also employed and their PU performance is compared. The results show the good performance and effectiveness of the Bayesian MRF modeling method. These experimental results are important references for phase unwrapping problems when phase discontinuities exist.

The output characteristics of high power ytterbium-doped fiber super-fluorescent sources were analyzed. 75.7W output power can be achieved when the 915nm pump power is 100W, and the fiber length is 10m.when the pump power changes from 20 to 100W, the backward super-fluorescent power is always larger than the forward. The mean wavelength of the forward and backward super-fluorescent is very stable. The spectrum width all decrease. The spectrum width of forward ASE changes from 24.8nm to 21.4nm when the pump power changes from 20 to 100W. The spectrum width of backward ASE changes from 25.5nm to 22.3nm.

this study presents an eight array ultrasonic signal phased array sparse sampling experiment system based ultrasonic phased array technology and Compressed Sensing (CS). Proposed system considers recovery ultrasonic beam signal received eight phased array elements with sparse samples captured using sub-Nyquist model in CS recovery algorithm. We have the block defect detection test in the system. The test result approximated the actual block defect position. Based on block defect detection test, We compared sparse sampling value using spectrum estimation to Compressed Sensing recovery algorithm imaging, and no focus and focus detection effect, proved the phased array experiment system based on Compressed Sensing .it can greatly improve the detection signal to noise ratio (SNR) and sensitivity. So we verify the phased array focus can improve the detection ability.

The most basic functions of wiper test system for modern high-grade cars are to provide accurate measurement of swing times of the wipers and real-time control of LIN wiper motor. In this paper, the design of a wiper test system composed of Hall sensor, LIN bus and MCU has been developed based on the research on Hall sensor and LIN bus. In the system, MCU is used to collect information of the swing counting sensors and controls the LIN motor. USB bus is chosen to interconnect the embedded system and the computer and counting sensors are responsible for wiper swing counting. Tests and actual operation showed that the wiper test system proposed in this paper is feasible, which offered automated wiper test and ensured quality of wipers. The system is of high practical application value.