摘要：The subthalamic nucleus(STN)is considered the best target for deep brain stimulation treatments of Parkinson’s disease(PD).It is difficult to localize the STN due to its small size and deep *** microelectrode arrays(MEAs)can rapidly and precisely locate the STN,which is important for precise *** this paper,16-channel MEAs modified with multiwalled carbon nanotube/poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)(MWCNT/PEDOT:PSS)nanocomposites were designed and fabricated,and the accurate and rapid identification of the STN in PD rats was performed using detection sites distributed at different brain *** results showed that nuclei in 6-hydroxydopamine hydrobromide(6-OHDA)-lesioned brains discharged more intensely than those in unlesioned *** addition,the MEA simultaneously acquired neural signals from both the STN and the upper or lower boundary nuclei of the ***,higher values of spike firing rate,spike amplitude,local field potential(LFP)power,and beta oscillations were detected in the STN of the 6-OHDA-lesioned brain,and may therefore be biomarkers of STN *** with the STNs of unlesioned brains,the power spectral density of spikes and LFPs synchronously decreased in the delta band and increased in the beta band of 6-OHDA-lesioned *** may be a cause of sleep and motor disorders associated with ***,this work describes a new cellular-level localization and detection method and provides a tool for future studies of deep brain nuclei.

摘要：Water-coupled charge blasting is a promising technique to efficiently break rock *** this study,numerical models of double boreholes with water-coupled charge are established using LS-DYNA and are calibrated by the tests of rock masses subjected to explosion loads to examine its *** crack levels of rock mass induced by water-coupled charge blasting and air-coupled charge blasting are first *** is found that water-coupled charge blasting is more appropriate to fracture deep rock mass than air-coupled charge *** addition,the effects of rock properties,water-coupled charge coefficients,and borehole connection angles on the performance of water-coupled charge blasting are *** results show that rock properties and water-coupled charge coefficients can greatly influence the crack and fragmentation levels of rock mass induced by water-coupled charge blasting under uniform and non-uniform in-situ ***,changing borehole-connection angles can only affect crack and fragmentation levels of rock mass under non-uniform in-situ stresses but barely affect those under uniform in-situ stresses.A formula is finally proposed by considering the above-mentioned factors to provide the design suggestion of water-coupled charge blasting to fracture rock mass with different in-situ stresses.

摘要：As a new three-dimensional(3-D)modulation,Polarization Quadrature Amplitude Modulation(PQAM) can be regarded as the combination of Pulse amplitude modulation(PAM) and Quadrature Amplitude Modulation(QAM) *** can better improve the digital communication efficiency and reduce the Symbol error rate(SER) of the system than one-dimensional or two-dimensional modulation *** to design a feasible constellation is the most concerned problem of PQAM *** paper first studies the relationship between the SER theoretical value of PQAM and the distribution of M and N,proposes a new M,N allocation ***,a new and straightforward design method of constructing higher-level 3-D signal constellations,which can be matched with the PQAM,and the constellation can divided into three different structures according to the ary for ***,the simulation results show that:in PQAM system,the modulation scheme and the constellation mapping scheme are proposed in this paper which can effectively reduce the system SER and improve the anti-noise performance of the system.

摘要：The recent decade has witnessed an upsurge in the demands of intelligent and simplified Internet of Things(IoT)networks that provide ultra-low-power communication for numerous miniaturized *** the research community has paid great attention to wireless protocol designs for these networks,researchers are handicapped by the lack of an energy-efficient software-defined radio(SDR)platform for fast implementation and experimental *** SDRs perform well in battery-equipped systems,but fail to support miniaturized IoT devices with stringent hardware and power *** paper takes the first step toward designing an ultra-low-power SDR that satisfies the ultra-low-power or even battery-free requirements of intelligent and simplified IoT *** achieve this goal,the core technique is the effective integration ofµW-level backscatter in our SDR to sidestep power-hungry active radio frequency *** carefully develop a novel circuit design for efficient energy harvesting and power control,and devise a competent solution for eliminating the harmonic and mirror frequencies caused by backscatter *** evaluate the proposed SDR using different modulation schemes,and it achieves a high data rate of 100 kb/s with power consumption less than 200µW in the active mode and as low as 10µW in the sleep *** also conduct a case study of railway inspection using our platform,achieving 1 kb/s battery-free data delivery to the monitoring unmanned aerial vehicle at a distance of 50 m in a real-world environment,and provide two case studies on smart factories and logistic distribution to explore the application of our platform.

摘要：The use of a reconfigurable intelligent surface(RIS)in the enhancement of the rate performance is considered to involve the limitation of the RIS being a passive *** address this issue,we propose a RIS-aided amplify-and-forward(AF)relay network in this *** jointly optimizing the beamforming matrix at AF relay and the phase-shift matrices at RIS,two schemes are put forward to address a maximizing signal-to-noise ratio(SNR)***,aiming at achieving a high rate,a high-performance alternating optimization(AO)method based on Charnes–Cooper transformation and semidefinite programming(CCT-SDP)is proposed,where the optimization problem is decomposed into three subproblems solved using CCT-SDP,and rank-one solutions can be recovered using Gaussian ***,the optimization variables in the CCT-SDP method are matrices,leading to extremely high *** reduce the complexity,a low-complexity AO scheme based on Dinkelbachs transformation and successive convex approximation(DT-SCA)is proposed,where the variables are represented in vector form,and the three decoupling subproblems are solved using *** results verify that compared to three benchmarks(i.e.,a RIS-assisted AF relay network with random phase,an AF relay network without RIS,and a RIS-aided network without AF relay),the proposed CCT-SDP and DT-SCA schemes can harvest better rate ***,it is revealed that the rate of the low-complexity DT-SCA method is close to that of the CCT-SDP method.

摘要：The style of Chinese Paintings reflects more obvious artistic characteristics of"beauty of artistic conception"and"beauty of space".However,analyzed fromthe perspective of"beauty of artistic conception",the root of beauty of artistic conception lies in the hierarchical guidance on aesthetic perspective,psychology and thinking,ultimately leading to the continuous widening of the artistic space embodied in Chinese paintings and leaving appreciators extensive artistic *** the artistic style of postmodern paintings emphasizes the abstractness of thinking as the basis and impels intuitive motivation of aesthetic perspective and psychology via the abstractness of aesthetic thinking,thus fully reflecting the postmodernist artistic characteristics of Chinese painting,and meanwhile continuously sublimating the artistic values implied in Chinese paintings.

摘要：增材制造技术凭借其生产几何复杂结构(如晶格结构)的能力而广受欢迎.在航天航空和汽车领域轻量化设计中,晶格结构具有极大的优势.众所周知,振动问题是航天航空结构设计广泛关注的问题之一,为了避免结构动力破坏,有必要开展结构振动频率研究,尤其是结构自振频率研究.本文针对一阶频率最大化问题,提出了一种维诺梯度随机晶格结构多尺度优化设计方法.首先,在微观尺度上进行了维诺随机晶格微观结构生成和分析.然后,采用无惩罚密度法进行宏观结构优化.最后,基于得到的相对密度分布和映射关系,重构了全尺度维诺梯度随机晶格结构.数值算例验证了该方法在维诺梯度随机晶格结构设计中的正确性和有效性,振动试验也验证了所提出的多尺度方法的有效性和优化的梯度晶格结构在结构动力响应方面的优势.

摘要：This paper proposes a compact polarization microstrip antenna based on double-layer *** bandwidth of the whole antenna is widened by expanding the top and bottom layers *** the design of antenna structure and adjustment of size,the proposed antenna can achieve both the left-and right-hand circular polarizations in 2.33 GHz-2.97 *** results indicate that the effective bandwidth is 640 MHz in S-band and the relative bandwidth can achieve 24% with 11 S less than 15 dB.

摘要：In this work, power efficient butterfly unit based FFT architecture is presented. The butterfly unit is designed using floating-point fused arithmetic units. The fused arithmetic units include two-term dot product unit and add-subtract unit. In these arithmetic units, operations are performed over complex data values. A modified fused floating-point two-term dot product and an enhanced model for the Radix-4 FFT butterfly unit are proposed. The modified fused two-term dot product is designed using Radix-16 booth multiplier. Radix-16 booth multiplier will reduce the switching activities compared to Radix-8 booth multiplier in existing system and also will reduce the area required. The proposed architecture is implemented efficiently for Radix-4 decimation in time(DIT) FFT butterfly with the two floating-point fused arithmetic units. The proposed enhanced architecture is synthesized, implemented, placed and routed on a FPGA device using Xilinx ISE tool. It is observed that the Radix-4 DIT fused floating-point FFT butterfly requires 50.17% less space and 12.16% reduced power compared to the existing methods and the proposed enhanced model requires 49.82% less space on the FPGA device compared to the proposed design. Also, reduced power consumption is addressed by utilizing the reusability technique, which results in 11.42% of power reduction of the enhanced model compared to the proposed design.

摘要：To obtain the peak response at 532nm, narrow-band response GaA1As photocathodes with two GaAIAs ac- tive layers of different aluminum compositions are designed in consideration of the maximum absorptivity and quantum efficiency. The transmission-mode and the corresponding reflective-mode photocathodes are grown by metalorganic chemical vapor deposition. The results indicate that the peak response and the cut-off wavelength occur at 532nm for the two kinds of photocathodes respectively. The response of the reflection-mode photoeath- ode is an order of magnitude higher than that of the transmission-mode photocathode, whereas the better growth quality and the thicker second GaAIAs active layer can improve the transmission-mode response.