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    题名 作者 年代 出处 被引量
1具备结构感知功能的倾斜摄影测量场景三维重建显示文摘倾斜摄影测量三维重建是当前摄影测量与计算机视觉领域的研究热点之一。相对于传统的垂直航空影像,倾斜影像具有同视影像基线较短、几何变形大、色差大、地物遮挡现象较为突出、数据量较大等特点,这给全自动的高精度三维建模带来了一系列困难和问题。肖雄武 李德仁(指导) 郭丙轩(指导) Hongkai Zhao(指导) 2019测绘学报2019,48,6:32
2Angular observation of joints of geckos moving on horizontal and vertical surfaces显示文摘Because of their outstanding climbing and motor coordination ability, geckos have provided the basis for a peculiar bionic model leading to the development of a geckorobot. A three-dimensional locomotion observation system was constructed to measure angular orientations of joints while geckos trotted (337.1 mm/s) and walked (66.7 mm/s) on horizontal surfaces, and trotted (241.5mm/s) and walked (30.6mm/s) on vertical surfaces. Moving over horizontal surfaces, the joints rotated more quickly the greater the speed, and the swinging scope of forelimbs stayed nearly at 59 degrees when swinging forward, but extended from 72 degrees to 79.2 degrees when swinging backward. The lifting angle of forelimbs was always positive to keep the center of mass close to the surface when moving up vertical surfaces, the scope of the forward swinging forelimbs forward extended from 33.7 degrees to 36.7 degrees with increasing speed, while the scope of backward swinging forelimbs remained almost the same at 87.5 degrees. Alternative gaits had little effect on the swing angle of hindlimbs of the geckos moving on both horizontal and vertical surfaces.LI HongKai DAI ZhenDong SHI AiJu ZHANG Hao SUN JiuRong 2009Chinese Science Bulletin2009,54,4:13
3Architecture design for reliable and reconfigurable FPGA-based GNC computer for deep space exploration显示文摘SRAM(static random access memory)-based FPGA(field programmable gate array), owing to its large capacity, high performance, and dynamical reconfiguration, has become an attractive platform for So PC(system on programmable chip) development. However, as the configuration memory and logic memory of the SRAM-based FPGA are highly susceptible to SEUs(single-event upsets) in deep space, it is a challenge to design and implement a highly reliable FPGA-based system for spacecraft, and no practical architecture has been proposed. In this paper, a new architecture for a reliable and reconfigurable FPGAbased computer in a highly critical GNC(guidance navigation and control) system is proposed. To mitigate the effect of an SEU on the system, multi-layer reconfiguration and multi-layer TMR(triple module redundancy) techniques are proposed, with a reliable reconfigurable real-time operating system(Space OS) managing the system level fault tolerance of the computer in the architecture. The proposed architecture for the reconfigurable FPGA-based computer has been implemented with COTS(commercial off the shelf) FPGA and has firstly been applied to the GNC system of a circumlunar return and reentry flight vehicle. The in-orbit results show that the proposed architecture is capable of meeting the requirements of high reliability and high availability, and can provide the expressive varying functionality and runtime flexibility for an FPGA-based GNC computer in deep space.YANG MengFei LIU Bo GONG Jian LIU HongJin HU HongKai DONG YangYang SHI Lei ZHAO YunFu MIAO ZhiFu 2016Science China(Technological Sciences)2016,59,2:10
4PARALLEL IMPLEMENTATIONS OF THE FAST SWEEPING METHOD显示文摘快大规模方法是为夸张问题的一个有效反复的方法。它把 Gauss-Seidel 重复与轮流出现打扫订相结合。在这篇论文,快大规模方法的几平行实现被介绍。这些平行算法由于内在的部分不同方程的诱发性简单、有效。数字例子被用来验证我们的算法。数学题目分类:65N06, 65N12, 65N55。Hongkai Zhao 2007Journal of Computational Mathematics2007,25,4:8
5Manipulation of Band Degeneracy and Lattice Strain for Extraordinary PbTe Thermoelectrics显示文摘Maximizing band degeneracy and minimizing phonon relaxation time are proven to be successful for advancing thermoelectrics.Alloying with monotellurides has been known to be an effective approach for converging the valence bands of PbTe for electronic improvements,while the lattice thermal conductivity of the materials remains available room for being further reduced.It is recently revealed that the broadening of phonon dispersion measures the strength of phonon scattering,and lattice dislocations are particularly effective sources for such broadening through lattice strain fluctuations.In this work,a fine control of MnTe and EuTe alloying enables a significant increase in density of electron states near the valence band edge of PbTe due to involvement of multiple transporting bands,while the creation of dense in-grain dislocations leads to an effective broadening in phonon dispersion for reduced phonon lifetime due to the large strain fluctuations of dislocations as confirmed by synchrotron X-ray diffraction.The synergy of both electronic and thermal improvements successfully leads the average thermoelectric figure of merit to be higher than that ever reported for p-type PbTe at working temperatures.Yixuan Wu Pengfei Nan Zhiwei Chen Zezhu Zeng Siqi Lin Xinyue Zhang Hongliang Dong Zhiqiang Chen Hongkai Gu Wen Li Yue Chen Binghui Ge Yanzhong Pei 2020Research2020,,1:6
6Characteristics of motorized spindle supported by active magnetic bearings显示文摘A motorized spindle supported by active magnetic bearings(AMBs) is generally used for ultra-high-speed machining. Iron loss of radial AMB is very great owing to high rotation speed, and it will cause severe thermal deformation. The problem is particularly serious on the occasion of large power application, such as all electric aero-engine. In this study, a prototype motorized spindle supported by five degree-of-freedom AMBs is developed. Homopolar and heteropolar AMBs are independently adopted as radial bearings. The influences of the two types of radial AMBs on the dynamic characteristics of the motorized spindle are comparatively investigated by theoretical analysis, test modal analysis and actual operation of the system. The iron loss of the two types of radial AMBs is analyzed by finite element software and verified through run-down experiments of the system. The results show that the structures of AMB have less influence on the dynamic characteristics of the motorized spindle. However, the homopolar structure can effectively reduce the iron loss of the radial AMB and it is useful for improving the overall performance of the motorized spindle.Xie Zhenyu Yu Kun Wen Liantang Wang Xiao Zhou Hongkai 2014Chinese Journal of Aeronautics2014,27,6:6
7Movement behavior of a spider on a horizontal surface显示文摘Studying the locomotive behavior of animals has the potential to inspire the design of the mechanism and gait patterns of robots ('bio-inspired robots'). The kinematics characteristics of a spider (Ornithoctonus huwena), including movement of the legs, movement of the center of mass (COM) and joint-rotation angle, were obtained from the observation of locomotion behaviors recorded by a three-dimensional locomotion observation system. Our results showed that one set of the stance phase consists of four legs, which were leg-1 and leg-3 on one side and leg-2 and leg-4 on the other side. Additionally, two sets of the stance phase comprised eight legs alternately supporting and driving the motion of the spider's body. The spider primarily increased its movement velocity by increasing stride frequency. In comparison to other insects, the spider, O. huwena, has superior movement stability. The velocity and height of COM periodically fluctuated during movement, reaching a maximum during alternation of leg phase, and falling to a minimum in the steady stance phase. The small change in deflection angle of the hind-leg was effective in driving locomotion, whereas each joint-rotation angle of the fore-leg changed irregularly during locomotion. This research will help in the design of bio-inspired robots, including the selection of gait planning and its control.WANG ZhouYi WANG JinTong JI AiHong LI HongKai DAI ZhenDong 2011Chinese Science Bulletin2011,56,25:5
8Fabrication of a hydroxyapatite-PDMS microfluidic chip for bone-related cell culture and drug screening显示文摘Bone is an important part of the human body structure and plays a vital role in human health.A microfluidic chip that can simulate the structure and function of bone will provide a platform for bone-related biomedical research.Hydroxyapatite(HA),a bioactive ceramic material,has a similar structure and composition to bone mineralization products.In this study,we used HA as a microfluidic chip component to provide a highly bionic bone environment.HA substrates with different microchannel structures were printed by using ceramic stereolithography(SLA)technology,and the minimum trench width was 50μm.The HA substrate with microchannels was sealed by a thin polydimethylsiloxane(PDMS)layer to make a HA-PDMS microfluidic chip.Cell culture experiments demonstrated that compared with PDMS,HA was more conducive to the proliferation and osteogenic differentiation of the human foetal osteoblast cell line(hFOB).In addition,the concentration gradient of the model drug doxorubicin hydrochloride(DOX)was successfully generated on a Christmas tree structure HA-PDMS chip,and the half maximal inhibitory concentration(IC50)of DOX was determined.The findings of this study indicate that the HA-PDMS microfluidic chip has great potential in the field of high-throughput bonerelated drug screening and bone-related research.Qiangqiang Tang Xiaoyu Li Chen Lai Lei Li Hongkai Wu Yingjun Wang Xuetao Shi 2021Bioactive Materials2021,6,1:5
9Analysis of severe human adenovirus infection outbreak in Guangdong Province,southern China in 2019显示文摘During 2018–2019,a severe human adenovirus(HAdV)infection outbreak occurred in southern China.Here,we screened 18 respiratory pathogens in 1704 children(≤14 years old)hospitalized with acute respiratory illness in Guangzhou,China,in 2019.In total,151 patients had positive HAdV test results;34.4%(52/151)of them exhibited severe illness.HAdV infection occurred throughout the year,with a peak in summer.The median patient age was 3.0(interquartile range:1.1–5.0)years.Patients with severe HAdV infection exhibited increases in12 clinical indexes(P≤0.019)and decreases in four indexes(P≤0.007),compared with patients exhibiting nonsevere infection.No significant differences were found in age or sex distribution according to HAdV infection severity(P>0.05);however,the distributions of comorbid disease and HAdV co-infection differed according to HAdV infection severity(P<0.05).The main epidemic types were HAdV-3(47.0%,71/151)and HAdV-7(46.4%,70/151).However,the severe illness rate was significantly higher in patients with HAdV-7(51.4%)than in patients with HAdV-3(19.7%)and other types of HAdV(20%)(P<0.001).Sequencing analysis of genomes/capsid genes of 13 HAdV-7 isolates revealed high similarity to previous Chinese isolates.A representative HAdV-7isolate exhibited a similar proliferation curve to the curve described for the epidemic HAdV-3 strain Guangzhou01(accession no.DQ099432)(P>0.05);the HAdV-7 isolate exhibited stronger virulence and infectivity,compared with HAdV-3(P<0.001).Overall,comorbid disease,HAdV co-infection,and high virulence and infectivity of HAdV-7 were critical risk factors for severe HAdV infection;these data can facilitate treatment,control,and prevention of HAdV infection.Wenkuan Liu Shuyan Qiu Li Zhang Hongkai Wu Xingui Tian Xiao Li Duo Xu Jing Dai Shujun Gu Qian Liu Dehui Chen Rong Zhou 2022Virologica Sinica2022,37,3:5
10Simulated annealing algorithm for the optimal translation sequence of the jth agent in rough communication显示文摘In rough communication, because each agent has a different language and cannot provide precise communication to each other, the concept translated among multi-agents will loss some information and this results in a less or rougher concept. With different translation sequences, the problem of information loss is varied. To get the translation sequence, in which the jth agent taking part in rough communication gets maximum information, a simulated annealing algorithm is used. Analysis and simulation of this algorithm demonstrate its effectiveness.Wang Hongkai Guan Yanyong Xue Peijun 2008Journal of Systems Engineering and Electronics2008,19,3:5
11Cuprizone-induced demyelination in mice: age-related vulner-ability and exploratory behavior deficit显示文摘Schizophrenia is a mental disease that mainly affects young individuals (15 to 35 years old) but its etiology remains largely undefined. Recently, accumulating evidence indicated that demyelination and/or dysfunction of oligodendrocytes is an important feature of its pathogenesis. We hypothesized that the vulnerability of young individuals to demyelination may contribute to the onset of schizophrenia. In the present study, three different age cohorts of mice, i.e. juvenile (3 weeks), young-adult (6 weeks) and middle-aged (8 months), were subjected to a 6-week diet containing 0.2% cuprizone (CPZ) to create an animal model of acute demyelination. Then, age-related vulnerability to CPZ-induced demyelination, behavioral outcomes, and myelination-related molecular biological changes were assessed. We demonstrated: (1) CPZ treatment led to more severe demyelination in juvenile and young-adult mice than in middle-aged mice in the corpus callosum, a region closely associated with the pathophysiology of schizophrenia; (2) the higher levels of demyelination in juvenile and young-adult mice were correlated with a greater reduction of myelin basic protein, more loss of CC-1-positive mature oligodendrocytes, and higher levels of astrocyte activation; and (3) CPZ treatment resulted in a more prominent exploratory behavior deficit in juvenile and young-adult mice than in middle-aged mice. Together, our data demonstrate an age-relatedvulnerability to demyelination with a concurrent behavioral deficit, providing supporting evidence for better understanding the susceptibility of the young to the onset of schizophrenia.Hongkai Wang Chengren Li Hanzhi Wang Feng Mei Zhi Liu Hai-Ying Shen Lan Xiao 2013Neuroscience Bulletin2013,29,2:4
12Cross-Scale Synthesis of Organic High-k Semiconductors Based on Spiro-Gridized Nanopolymers显示文摘High dielectric constants in organic semiconductors have been identified as a central challenge for the improvement in not only piexoelectric,preolecric,and freeltric efcts but also photoclecric conversion eficiency in OPVs,carrier mobility in OFETS,and charge density in charge-trapping memories.Herein,we report an ultralong persistence length(≈41 nm)efet of spiro-fused organic nanopolymers on dielectric properties,together with excitonic and charge carrier behaviors.The state-of-the-art nanopolymers,namely,nanopolyspirogrids(NPSGs),are synthesized via the simple crossscale Friedel-Crafts polygridlization of AjB-type nanomonomers.The high dielectric constant(k=8.43)of NPSG is firstly achieved by locking spiro-polygridization efect that results in the enhancement of dipole polarization.When doping into a polystyrene-based dielectric layer,such a high-k feature of NPSG increases the feld-ffct carrier mobility from 0.20 to 0.90cm^(2)Vl s'in pentacene OFET devices.Meanwhile,amorphous NPSG film exhibits an ultralow energy disorder(<50 meV)for an exellent zero-field hole mobility of 3.94×10^(-1)cm^(2)V^(-1)s^(-1).surpassing most of the amorphousπconjugated polymers Onganic nanopolymers with high dielectric constants open a new way to break through the bottleneck of eficiency and multifunctionality in the blueprint of the fourth generation semiconductors.Dongqing Lin Wenhua Zhang Hang Yin Haixia Hu Yang Li He Zhang Le Wang Xinmiao Xie Hongkai Hu Yongxia Yan Haifeng Ling Jin'an Liu Yue Qian Lei Tang Yongxia Wang Chaoyang Dong Linghai Xie Hao Zhang Shasha Wang Ying Wei Xuefeng Guo Dan Lu Wei Huang 2022Research2022,,2:3
13Security in Wireless Mesh Neworks: Challenges and Solutions显示文摘Wireless mesh network is a new emerging field with its potential applications in extremely unpredictable and dynamic environments.However,it is particularly vulnerable due to its features of open medium,dynamic changing topology, cooperative routing algorithms.The article surveys the state of the art in security for wireless mesh networks.Firstly,we analyze various possible threats to security in wireless mesh networks.Secondly,we introduce some representative solutions to these threats,including solutions to the problems of key management,secure network routing,and intrusion detection.We also provide a comparison and discussion of their respective merits and drawbacks,and propose some improvements for these drawbacks.Finally,we also discuss the remaining challenges in the area.Yi Ping Xing Hongkai Wu Yue Li Jianhua 2009China Communications2009,6,3:3
14Geographical Patterns of Chinese Ethnic Minority Population Composition and Ethnic Diversity显示文摘Ethnicity is a carrier of language and culture.Spatial distribution of ethnic diversity is fundamental for identifying and reconstructing the migration patterns and evolution histories of cultures and languages.Utilizing the Chinese 4th National Census (1990) data,we investigated the specific time geographical patterns of population and diversity of Chinese ethnicminorities.As anticipated,results show that Chineseminorities are chiefly concentrated in dis-tant plateaus and mountains in the southwest,northwest and northeast of China.Further,population density centers of the 10 majorminorities are rather scattered,alternatively dominating at different parts of the country.This study pro-vides a first comprehensive quantitative test on a prevailing notion of 'six plates and three corridors' on the empirical clustering patterns of Chinese ethnicminorities.There are more consistent evidences supporting this notion in the north of China,with the central and southern regions showing more complex patterns,potentially transformed by processes such as migration,fragmentation,and percolation.The results of this study suggest that a geographical ap-proach can provide heuristic and complementary information for better understanding of historical social processes.SHEN Zehao LI Peng SUN Hongkai PANG Lihua 2011Chinese Geographical Science2011,21,4:3
15Rough communication of crisp concept in fuzzy approximation spaces显示文摘To study the problem of knowledge translation in fuzzy approximation spaces, the concept of rough communication of crisp set in fuzzy approximation spaces is proposed. In a rough communication of crisp set in fuzzy approximation spaces, the problem of uncertainty exists, for each agent has a different language and cannot provide precise communication to each other. By means of some concepts, such as CF rough communication cut, which is a bridge between fuzzy concept and crisp concept, cut analysis of CF rough communication is made, and the relation theorem between CF rough communication and rough communication of crisp concept is obtained. Finally, in order to give an intuitive analysis of the relation between CF rough communication and rough communication of crisp concept, an example is given.Wang Hongkai Guan Yanyong Yu Zhaoxia 2009Journal of Systems Engineering and Electronics2009,20,2:3
16Kruppel-like factor 10 protects against acute viral myocarditis by negatively regulating cardiac MCP-1 expression显示文摘Viral myocarditis(VMC)is a cardiac disease associated with myocardial inflammation and injury induced by virus infection.Cardiomyocytes have recently been regarded as key players in eliciting and modulating inflammation within the myocardium.Kruppel-like factor 10(KLF10)is a crucial regulator of various pathological processes and plays different roles in a variety of diseases.However,its role in VMC induced by coxsackievirus B3(CVB3)infection remains unknown.In this study,we report that cardiac KLF10 confers enhanced protection against viral myocarditis.We found that KLF10 expression was downregulated upon CVB3 infection.KLF10 deficiency enhanced cardiac viral replication and aggravated VMC progress.Bone marrow chimera experiments indicated that KLF10 expression in nonhematopoietic cells was involved in the pathogenesis of VMC.We further identified MCP-1 as a novel target of KLF10 in cardiomyocytes,and KLF10 cooperated with histone deacetylase 1(HDAC1)to negatively regulate MCP-1 expression by binding its promoter,leading to activation of MCP-1 transcription and recruitment of Ly6C^(high) monocytes/macrophages into the myocardium.This novel mechanism of MCP-1 regulation by KLF10 might provide new insights into the pathogenesis of VMC and a potential therapeutic target for VMC.Jie Yang Hongkai Zhang Xuelian Wang Jing Guo Lin Wei Yahui Song Yuan Luo YinXia Zhao Malayannan Subramaniam Thomas C.Spelsberg Lie Wang Wei Xu Min Li 2021Cellular & Molecular Immunology2021,18,9:3
17Motion Control of Capsule-like Underwater Robot Utilizing the Swing Properties of Ionic Polymer Metal Composite Actuators显示文摘Ionic Polymer Metal Composite(IPMC)is a novel electrically actuated intelligent material with the advantages of big bending displacement,low driving voltage,flexible and so on.It has been recognized as one of the most attractive actuators with prospective applications for underwater robots and bionic organs.In this work,a capsule-like robot was introduced with the pectoral and caudal fins made of IPMC.By analyzing the properties of displacement response to square waves with different frequencies and low level voltages,it was found that performance of IPMC are frequency sensitive.Besides,when the absolute value of low level voltage decreases,IPMC could swing on one side with the decrease in amplitudes,whereas the amplitude at high level voltage fluctuates within small ranges at low frequencies.IPMC tip can approximately maintain when the frequency of driving signal around 30 Hz.Such properties were employed to control the locomotion of robot combining the motions of pectoral and caudal fin.Thus,the locomotions of swimming forward,turning and positioning were realized.Hongkai Li Min Fan Yinghao Yue Guoliang Hu Qingsong He Min Yu 2020Journal of Bionic Engineering2020,17,2:3
18Bract suppression regulated by the miR156/529-SPLs-NL1-PLA1 module is required for the transition from vegetative to reproductive branching in rice显示文摘Reproductive transition of grasses is characterized by switching the pattern of lateral branches,featuring the suppression of outgrowth of the subtending leaves(bracts)and rapid formation of higher-order branches in the inflorescence(panicle).However,the molecular mechanisms underlying such changes remain largely unknown.Here,we show that bract suppression is required for the reproductive branching in rice.We identified a pathway involving the intrinsic time ruler microRNAI56/529,their targets SQUAMOSA PROMOTER BINDING PROTEIN LIKE(SPL)genes,NECK LEAF1(NL1),and PLASTOCHRON1(PLA1),which regulates the bract outgrowth and thus affects the pattern switch between vegetative and reproductive branching.Suppression of the bract results in global reprogramming of transcriptome and chromatin accessibility following the reproductive transition,while these processes are largely dysregu-lated in the mutants of these genes.These discoveries contribute to our understanding of the dynamic plant architecture and provide novel insights for improving crop yields.Lei Wang Luchang Ming Keyan Liao Chunjiao Xia Shengyuan Sun Yu Chang Hongkai Wang Debao Fu Conghao Xu Zhengji Wang Xu Li Weibo Xie Yidan Ouyang Qinglu Zhang Xianghua Li Qinghua Zhang Jinghua Xiao Qifa Zhang 2021Molecular Plant2021,14,7:2
19A simple fabricated thickness-based stiffness gradient for cell studies显示文摘In this work, we developed a simple method to fabricate a thickness-based continuous stiffness gradient for biological studies. It was made by glass slides, polydimethylsiloxane(PDMS) pre-polymer, spacer and clips only, without any sophisticated equipment. It is easy to fabricate in any general biological and pharmaceutical laboratories. The stiffness gradient was characterized in terms of apparent Young's modulus by atomic force microscopy(AFM) and the Young's modulus along the gradient was found to be 8.5–120 k Pa, which is within the physiological relevant range. He La-C3 cells were cultured on the gradient to study their morphological behavior according to the substrate stiffness. Furthermore, the drug efficiency of etoposide, an anti-cancer drug, was studied along the substrate stiffness gradient. It was found that He La-C3 cells cultured on the soft region of the gradient(8.5–11 k Pa) are more sensitive to etoposide. We believe the proposed device could promote cell investigations and drug screenings on a substrate with comparable stiffness to the native tissue.Yiwei Shu HO Nam Chan Dongshi Guan Hongkai Wu Lan Ma 2017Science Bulletin2017,62,3:2
20Mechanical property of U-Shaped 65Mn steel bumpers for seismic base isolation显示文摘This study proposes a novel U-shaped 65Mn steel bumper as the displacement restraining device for base-isolated structures with laminated elastomeric rubber bearings.A series of bumpers with different geometric parameters were designed and tested under monotonic and cyclic quasi-static loading protocols.The experimental results from a total of 232 specimens were analyzed to develop an analytical model to calculate the backbone curve and the maximum elastic restoring force for U-shaped 65Mn bumpers.Thus,the analytical equations to calculate the elastic,hardening,and unloading stiffness of U-shaped 65Mn bumpers,as well as their maximum elastic restoring force,are validated by using an additional ten groups of bumpers with varying radiuses.These analytical equations can accurately predict the mechanical parameters of U-shaped 65Mn steel bumpers for a design purpose.Han Miao Wang Yuandong Du Hongkai Cui Xiangdong 2021Earthquake Engineering and Engineering Vibration2021,20,3:2
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