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Due to the advantages of small form factor, high performance, low power consumption, and high density integration, three-dimensional integrated circuits (3D ICs) have been generally acknowledged as the next generation semiconductor technology. Low temperature bonding is the key technology to ensure the chip (or wafer) stacking in 3D ICs. In this paper, different low temperature bonding methods for chip (or wafer) stacking were reviewed and described systematically. Materials, processing and reliability will be extremely important, their effects on the 3D IC structure were addressed in detail, the challenging reliability issues may be considered as the major concern in the future work. The latest development of low temperature bonding in 3D ICs is also given here, which helpful may provide a reference for the further study of low temperature bonding.

Recent exciting findings of the biological interactions of graphene materials have shed light on potential biomedical applications of graphene-containing composites. Owing to the superior mechanical properties and low coefficient of thermal expansion, graphene has been widely used in the reinforcement of biocomposites. In the present study, various ratios of graphene (0.25wt%, 0.5wt% and 1.0wt%) were reinforced into calcium silicate (CS) for bone graft application. Results show that the graphene was embedded in the composites homogeneously. Adding 1wt% graphene into CS increased the young's modulus by ~47.1%. The formation of bone-like apatite on a range of composites with graphene weight percentages ranging from 0 to 1 has been investigated in simulated body fluid. The presence of a bone-like apatite layer on the composites surface after immersion in simulated body fluid was considered by scanning electron microscopy. In vitro cytocompatibility of the graphene-contained CS composites was evaluated using human marrow stem cells (hMSCs). The proliferation and alkaline phosphatase, osteopontin and osteocalcin osteogenesis-related protein expression of the hMSCs on the 1wt% graphene-contained specimens showed better results than on the pure CS. In addition, the angiogenesis-related protein (vWF and ang-1) secretion of cells was significantly stimulated when the graphene concentration in the composites was increased. These results suggest that graphene-contained CS bone graft are promising materials for bone tissue engineering applications.

Quadruped robots have been widely applied for the advantage of flexible mobile way. However, most of quadruped robots have large inertia and an impact load between the foot endpoint and ground in the process of movement because of series connection way. In order to solve the problems, a new mechanism of quadruped robot is designed and analyzed based on the active flexible joint with variable stiffness.

The microstructure of pre-aged AA7085 rolled plate was studied by means of hardness tests, optical microscopy, scanning electron microscopy, transmission electron microscopy, X-ray diffraction and electrical conductivity tests. The results show that supper refined and homogeneous precipitates were formed during pre-aging, but the hardness of the alloy was still relatively low. There occurred a large number of dislocations when the warm deformation was introduced, and the size of the intragranular precipitates firstly increases and then decreases and then increases with the dislocation density increasing, which was caused by the role of dislocations on inhibiting the formation of GP zone and promoting the nucleation and transformation ofηphase. Meanwhile, the distribution of grain boundary precipitates also changed from continuous chain to coarsening interrupted distribution and the precipitate free zone (PFZ) broadened obviously.

In the environment of harsh weather or obstacles, the corresponding monitoring department can't achieve remote control and acquire the accurate location of the unmanned aerial vehicle (UAV). According to the existing problem this paper designs a logical control module based on single chip microcomputer (SCM) C8051F040 and UAV real-time tracking system which is positioned by GPS. In this design, through the analysis and extraction of the GPS data, then transmit these data to the host computer through the USB interface with high speed, the unmanned aerial vehicle (UAV) flight vector position such as longitude and altitude information will be displayed by the host computer. After tested for several times, this vector pursuit system can acquire the accurate position of the unmanned aerial vehicle (UAV) and the corresponding flight path within 20 km. To some extent, it provides an effective guarantee for the remote control and monitoring department.