Rotation-invariant and controllable space-variant optical correlation

We propose a method for designing a correlator for achieving rotation-invariant and controllable space-variant optical correlation. The design concept is based on a combination of fractional correlation and circular-harmonic decomposition of the reference object. The suggested method is described and analyzed in detail. Numerical simulations show that this new correlator might provide potential applications in practice.     

多目的IP传输设计实现

组播因其在点对多点传输方面拥有的优势,常被用于多媒体会议等应用。但是由于使用组播路由规模的限制,阻碍了在因特网推广组播技术的应用。首先对组播的原理作了分析,提出了具有组播特性的包含多个目的IP地址的IP传输设计,然后描述了一些关键问题,并讲解了具体设计和实现方法。     

Silicon-based microelectrode arrays for stimulation and signal recording of in vitro cultured neurons

Microelectrode arrays (MEAs) for stimulation and signal recording of in vitro cultured neurons are presented.Each MEA is composed of 60 independent electrodes with 59 working ones and one reference one.These electrodes are divided into 30 pairs.Through each pair of electrodes,four independent states can be realized to define the accessing modes of neurons cultured on the surface of the electrodes.A total MEA covers an area of 10 mm×10 mm.MEAs are fabricated in a silicon-based semiconductor process.An implemented MEA is bonded on a specially designed printed-circuit-board (PCB) and surrounded by a culture chamber.An impedance measurement has been made to verify the electrical characteristics of MEAs.The surface was modified to enhance the biocompatibility.A series of PC12 cells culture experiments validates the effectiveness of the modification.An extracellular signal recording experiment with acetylcholine (Ach) as a stimulant has been carried out,and the results show the feasibility of MEAs for extracellular action potential recording.Extracellular electrical stimulation and recording experiments have been carried out too.They indicate that MEAs can be used for extracellular stimulation,recording,simultaneous stimulation and recording,and isolation of PC12 cells network cultured in vitro.     

Nanotextured superhydrophobic micromesh

A superhydrophobic micromesh covered with nanoprotrusions has been introduced and its applicability to a waterproof mobile phone speaker has been evaluated. The nanotextured superhydrophobic micromesh showed excellent water repellency, self-cleaning and waterproofing performances. In a waterproof speaker test using the fabricated nanotextured micromesh, the micromesh did not lose its waterproof function at 2 m water depth and did not form a remnant water film after being removed from the water. The packaged speaker showed almost the same sound quality before and after dipping at a 2 m water depth. These results demonstrate that the superhydrophobic nanotextured micromesh could be directly applicable for various products that need to resist water penetration, yet allow the transmission of gases and sound/light waves.