摘要：1 Introduction—starting at noetic science One question that has long puzzled the artificial intelligence(Al)community is:Can Al be creative?Or,can the reasoning process be creative?Starting at noetic science,this paper discusses the issues of visual knowledge representation and its potential applications to machine *** this paper,we enumerate related research on imagery-thinking-based reasoning,then focus on a special type of visual knowledge representation,i.e.,visual scene graph,and finally review the problem of visual scene graph construction and its potential applications in detail.

摘要：Transverse pressure gradient(TPG)is one of the key factors influencing the boundary layer airflow diversion in a bump *** paper proposes a novel TPG-based hypersonic bump inlet design *** method consists of two ***,a parametric optimization approach is employed to design a series of 2D inlets with various compression ***,according to the prescribed TPG,the optimized inlets are placed in different osculating planes to generate a 3D bump *** method provides a means to directly control the aerodynamic parameters of the bump rather than the geometric *** performing this method to a hypersonic chin inlet,a long and wide bump surface is formed in the compression wall,which leads to good integration of the bump/*** show that a part of the near-wall boundary layer flow is diverted by the bump,resulting in a slight decrease in the mass flow but a significant improvement in the total pressure *** addition,the starting ability is significantly improved by adding the bump *** reveals that the bump has a 3D rebuilding effect on the large-scale separation bubble of the unstarted ***,a mass flow correction is performed on the designed bump inlet to increase the mass flow to full airflow *** results show that the mass flow rate of the corrected bump inlet reaches up to 0.9993,demonstrating that the correction method is effective.

摘要：The demand of high-end electromagnetic wave absorbing materials puts forward higher requirements on comprehensive performances of small thickness,lightweight,broadband,and strong ***,a novel multi-layer stepped metamaterial absorber with gradient electromagnetic properties is *** complex permittivity and permeability of each layer are tailored via the proportion of carbonyliron and carbon-fiber dispersing into the epoxy *** proposed metamaterial is further optimized via adjusting the electromagnetic parameters and geometric sizes of each *** with the four-layer composite with gradient electromagnetic properties which could only realize reflection loss(RL)of less than−6 dB in 2.0-40 GHz,the optimized stepped metamaterial with the same thickness and electromagnetic properties realizes less than−10 dB in the relevant frequency ***,the RL of less than−15 dB is achieved in the frequency range of 11.2-21.4 GHz and 28.5-40 *** multiple electromagnetic wave absorption mechanism is discussed based on the experimental and simulation results,which is believed to be attributed to the synergy effect induced by multi-scale structures of the ***,combining multi-layer structures and periodic stepped structures into a novel gradient absorbing metamaterial would give new insights into designing microwave absorption devices for broadband electromagnetic protections.

摘要：局部电荷的强离域和强偶极矩是影响共价有机框架(COFs)基光催化剂催化析氢性能的两个关键因素.然而,基于精确的调控结构模型来系统研究这种构效关系的报告相对较少.本研究提出了一种新的策略,通过合理的设计,制备了三种三芴酮基COFs,通过在分子水平上调控单体的结构和偶极来提高局部电荷离域指数.我们重点研究这三种三芴酮基COF的局部电荷离域与光催化性能之间的构效关系.在不同三芴酮基COF中,1,3,5-三(对甲酰基苯基)苯基COF(TeTpb-COF)展现出21.6 mmol g^(-1)h^(-1)的最高析氢速率,与2,4,6-三(4-醛基苯基)-1,3,5-三嗪基COF(TeTt-COF,0.2mmol g^(-1)h^(-1))相比,光催化析氢性能提高了108倍.这种性能的增强可归因于其强大的分子内置电场提高了供体-受体嵌段单元中光生电荷的有效分离效率.这项工作证实了调整构建块可以极大增强三芴酮基COFs中的局部偶极矩,从而显著改善光催化析氢性能.构建模块的调控策略为创建高效的新型COF基光催化析氢平台提供了新机会.

摘要：Owing to their excellent mechanical flexibility, electrical conductivity, and biocompatibility, conductive hydrogels(CHs) are widely used in the fields of energy and power, and biomedical technology. To arrive at a better understanding of the design methods and development trends of CHs, this paper summarizes and analyzes related research published in recent years. First,we describe the properties and characteristics of CHs. Using Scopus, the world’s largest abstract and citation database, we conducted a quantitative analysis of the related literature from the past 15 years and summarized development trends in the field of CHs. Second, we describe the types of CH network crosslinking and basic functional design methods and summarize the three-dimensional(3D) structure-forming methods and conductive performance tests of CHs. In addition, we introduce applications of CHs in the fields of energy and power, biomedical technology, and others. Lastly, we discuss several problems in current CH research and introduce some prospects for the future development of CHs.

摘要：At present,metal-organic framework(MOF)-derived nano-micro architectures are actively explored for electromagnetic(EM)wave absorption owing to their flexible composition and structural manipulation that enhance dielectric and magnetic ***,the basic design principles in MOF-derived microwave absorption materials have not been *** review is devoted to analyzing design principles in MOF-derived microwave absorption materials from the following perspectives:diverse monomers(ligands and ions of MOFs),topologies,chemical states,and physical *** derived essential information regarding the EM wave absorption mechanism and the structural-functional dependency is also comprehensively ***,a clear insight into the challenges and perspectives of the industrial revolution upgrading in this promising field is proposed.

摘要：Designing strong, yet ductile, and body-centered cubic(BCC) medium-entropy alloys(MEAs) remains to be a challenge *** this study, the strength–ductility trade-off of Ni_(0.6)CoFe_(1.4)MEAs was tackled via introducing a BCC + face-centered cubic(FCC) dual-phase microstructure. Ni_(0.6)CoFe_(1.4)Nbx(x = 0, 0.05, 0.08, 0.10, and 0.15, in molar ratio) MEAs were prepared using vacuum induction melting. Results show that the new alloy is composed of BCC plus FCC dual phases featuring a network-like structure, and the BCC phase is the main phase in this alloy system. Moreover, the Nb0.10 MEA shows high strength and respectable tensile ductility, representing the best combination of the strength and fracture elongation among the alloys studied here. The remarkable strength of the Nb0.10 MEA is attributed to the combined effect of the solid solution strengthening, the precipitation hardening effect and the interface strengthening effect.

摘要：In the past few decades,robotics research has witnessed an increasingly high interest in miniaturized,intelligent,and integrated *** imperative component of a robot is the actuator that determines its *** traditional rigid drives such as motors and gas engines have shown great prevalence in most macroscale circumstances,the reduction of these drives to the millimeter or even lower scale results in a significant increase in manufacturing difficulty accompanied by a remarkable performance *** robots driven by living cells can be a potential solution to overcome these drawbacks by benefiting from the intrinsic microscale self-assembly of living tissues and high energy efficiency,which,among other unprecedented properties,also feature flexibility,self-repair,and even multiple degrees of *** paper systematically reviews the development of biohybrid ***,the development of biological flexible drivers is introduced while emphasizing on their advantages over traditional ***,up-to-date works regarding biohybrid robots are reviewed in detail from three aspects:biological driving sources,actuator materials,and structures with associated control ***,the potential future applications and major challenges of biohybrid robots are explored.

摘要：Owing to the inherent central information processing and resource management ability,the cloud radio access network(C-RAN)is a promising network structure for an intelligent and simplified sixth-generation(6G)wireless ***,to further enhance the capacity and coverage,more radio remote heads(RRHs)as well as high-fidelity and low-latency fronthaul links are required,which may lead to high implementation *** address this issue,we propose to exploit the intelligent reflecting surface(IRS)as an alternative way to enhance the C-RAN,which is a low-cost and energy-efficient ***,we consider the uplink transmission where multi-antenna users communicate with the baseband unit(BBU)pool through multi-antenna RRHs and multiple IRSs are deployed between the users and *** can conduct either point-to-point(P2P)compression or Wyner-Ziv coding to compress the received signals,which are then forwarded to the BBU pool through fronthaul *** investigate the joint design and optimization of user transmit beamformers,IRS passive beamformers,and fronthaul compression noise covariance matrices to maximize the uplink sum rate subject to fronthaul capacity constraints under P2P compression and Wyner-Ziv *** exploiting the Arimoto-Blahut algorithm and semi-definite relaxation(SDR),we propose a successive convex approximation approach to solve non-convex problems,and two iterative algorithms corresponding to P2P compression and Wyner-Ziv coding are *** results verify the performance gain brought about by deploying IRS in C-RAN and the superiority of the proposed joint design.

摘要：弹性超材料可被用于实现多种特殊功能,例如振动控制和波操纵,其中吸声是声学超材料完成的典型任务.利用机器学习方法反向设计超材料因利用数据驱动且不依赖经验的优势而备受关注,成为重要的设计范式之一.但现有的工作大多集中在验证反向设计神经网络的设计准确性,很少有人探索如何利用神经网络进行反向设计以提高材料性能.为此,我们的工作研究了反向设计框架在提升3D多尺度空腔型声学超材料的声学性能方面的能力.框架中有正向和反向网络,在训练过程中将目标吸声曲线(100~10000 Hz)作为反向网络的输入,并输出具有满足此吸声曲线的相应超材料结构,随后将其输入正向网络进行声学性能评估.结果表明,经过训练的前向网络可对超过训练集结构参数范围的结构(既“未见过”的结构)进行高精度性能预测,因此具有较高泛化性能.更重要的是,反向网络能够自发地采用超出范围限制的结构参数,以确保满足平均吸声系数高于训练集中任何数据的吸声目标,因此可利用反向设计突破训练集中数据的声学性能,进行性能优化.通过超限探索,反向设计精度从仅有9.2%的设计拥有<0.0001的均方误差显着提高到99.6%.最后,利用案例证明神经网络拥有的超限探索能力对旨在提高性能的反向设计有重要意义.希望这项工作能为更高性能弹性超材料的优化设计提供支撑.