|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Planar liquid crystal polarization optics for augmented reality and virtual reality: from fundamentals to applications显示文摘Planar and ultrathin liquid crystal(LC)polarization optical elements have found promising applications in augmented reality(AR),virtual reality(VR),and photonic devices.In this paper,we give a comprehensive review on the operation principles,device fabrication,and performance of these optical elements.Optical simulations methods for optimizing the device performance are discussed in detail.Finally,some potential applications of these devices in AR and VR systems are illustrated and analyzed. | Jianghao Xiong Shin-Tson Wu | 2021 | eLight2021，1，1： | 38 |
| 2 | Augmented reality and virtual reality displays:emerging technologies and future perspectives显示文摘With rapid advances in high-speed communication and computation,augmented reality(AR)and virtual reality(VR)are emerging as next-generation display platforms for deeper human-digital interactions.Nonetheless,to simultaneously match the exceptional performance of human vision and keep the near-eye display module compact and lightweight imposes unprecedented challenges on optical engineering.Fortunately,recent progress in holographic optical elements(HOEs)and lithography-enabled devices provide innovative ways to tackle these obstacles in AR and VR that are otherwise difficult with traditional optics.In this review,we begin with introducing the basic structures of AR and VR headsets,and then describing the operation principles of various HOEs and lithography-enabled devices.Their properties are analyzed in detail,including strong selectivity on wavelength and incident angle,and multiplexing ability of volume HOEs,polarization dependency and active switching of liquid crystal HOEs,device fabrication,and properties of micro-LEDs(light-emitting diodes),and large design freedoms of metasurfaces.Afterwards,we discuss how these devices help enhance the AR and VR performance,with detailed description and analysis of some state-of-the-art architectures.Finally,we cast a perspective on potential developments and research directions of these photonic devices for future AR and VR displays. | Jianghao Xiong En-Lin Hsiang Ziqian He Tao Zhan Shin-Tson Wu | 2021 | Light(Science & Applications)2021，10，11： | 27 |
| 3 | The influence of the wake of a flapping wing on the production of aerodynamic forces显示文摘The effect of the wake of previous strokes on the aerodynamic forces of a flapping model insect wing is studied using the method of computational fluid dynamics. The wake effect is isolated by comparing the forces and flows of the starting stroke (when the wake has not developed) with those of a later stroke (when the wake has developed). The following has been shown. (1) The wake effect may increase or decrease the lift and drag at the beginning of a half-stroke (downstroke or upstroke), depending on the wing kinematics at stroke reversal. The reason for this is that at the beginning of the half-stroke, the wing 'impinges' on the spanwise vorticity generated by the wing during stroke reversal and the distribution of the vorticity is sensitive to the wing kinematics at stroke reversal. (2) The wake effect decreases the lift and increases the drag in the rest part of the half-stroke. This is because the wing moves in a downwash field induced by previous half-stroke's starting vortex, tip vortices and attached leading edge vortex (these vortices form a downwash producing vortex ring). (3) The wake effect decreases the mean lift by 6%-18% (depending on wing kinematics at stroke reversal) and slightly increases the mean drag. Therefore, it is detrimental to the aerodynamic performance of the flapping wing. | Jianghao Wu Mao Sun | 2005 | Acta Mechanica Sinica2005，21，5： | 8 |
| 4 | Unsteady Aerodynamic Forces and Power Consumption of a Micro Flapping Rotary Wing in Hovering Flight显示文摘 | Chao Zhou Yanlai Zhang Jianghao Wu | 2018 | Journal of Bionic Engineering2018，15，2： | 6 |
| 5 | Control for going from hovering to small speed flight of a model insect显示文摘The longitudinal steady-state control for goingfrom hovering to small speed flight of a model insect isstudied, using the method of computational fluid dynamicsto compute the aerodynamic derivatives and the techniquesbased on the linear theories of stability and control for determiningthe non-zero equilibrium points. Morphological andcertain kinematical data of droneflies are used for the modelinsect. A change in the mean stroke angle (δ(?)) results in ahorizontal forward or backward flight; a change in the strokeamplitude (δΦ)or a equal change in the down- and upstrokeangles of attack (δα1) results in a vertical climb or decent;a proper combination of δ(?) and δΦ controls (or δ(?) and δα1controls) can give a flight of any (small) speed in any desireddirection. | Jianghao Wu Mao Sun | 2009 | Acta Mechanica Sinica2009，25，3： | 5 |
| 6 | Automated Kinematics Measurement and Aerodynamics of a Bioinspired Flapping Rotary Wing显示文摘 | Jianghao Wu Jian Qiu Yanlai Zhang | 2017 | Journal of Bionic Engineering2017，14，4： | 5 |
| 7 | Unsteady aerodynamic forces and power requirements of a bumblebee in forward flight显示文摘Aerodynamic forces and power requirements in forward flight in a bumblebee (Bombus terrestris) were studied using the method of computational fluid dynamics. Actual wing kinematic data of free flight were used in the study (the speed ranges from 0 m/s to 4.5 m/s; advance ratio ranges from 0-0.66). The bumblebee employs the delayed stall mechanism and the fast pitching-up rotation mechanism to produce vertical force and thrust. The leading-edge vortex does not shed in the translatory phase of the half-strokes and is much more concentrated than that of the fruit fly in a previous study. At hovering and low-speed flight, the vertical force is produced by both the half-strokes and is contributed by wing lift; at medium and high speeds, the vertical force is mainly produced during the downstroke and is contributed by both wing lift and wing drag. At all speeds the thrust is mainly produced in the upstroke and is contributed by wing drag.The power requirement at low to medium speeds is not very different from that of hovering and is relatively large at the highest speed (advance ratio 0.66), i.e. the power curve is Jshaped. Except at the highest flight speed, storing energy elastically can save power up to 20%-30%. At the highest speed,because of the large increase of aerodynamic torque and the slight decrease of inertial torque (due to the smaller stroke amplitude and stroke frequency used), the power requirement is dominated by aerodynamic power and the effect of elastic storage of energy on power requirement is limited. | Jianghao Wu Mao Sun | 2005 | Acta Mechanica Sinica2005，21，3： | 4 |
| 8 | Topology optimization in lightweight design of a 3D-printed flapping-wing micro aerial vehicle显示文摘Topology optimization is an effective method to obtain a lightweight structure that meets the requirements of structural strength.Whether the optimization results meet the actual needs mainly depends on the accuracy of the material properties and the boundary conditions,especially for a tiny Flapping-wing Micro Aerial Vehicle(FMAV)transmission system manufactured by 3D printing.In this paper,experimental and numerical computation efforts were undertaken to gain a reliable topology optimization method for the bottom of the transmission system.First,the constitutive behavior of the ultraviolet(UV)curable resin used in fabrication was evaluated.Second,a numerical computation model describing further verified via experiments.Topology optimization modeling considering nonlinear factors,e.g.contact,friction and collision,was presented,and the optimization results were verified by both dynamic simulation and experiments.Finally,detailed discussions on different load cases and constraints were presented to clarify their effect on the optimization.Our methods and results presented in this paper may shed light on the lightweight design of a FMAV. | Long CHEN Yanlai ZHANG Zuyong CHEN Jun XU Jianghao Wu | 2020 | Chinese Journal of Aeronautics2020，33，12： | 4 |
| 9 | Sustained‑Release Nanocapsules Enable Long‑Lasting Stabilization of Li Anode for Practical Li‑Metal Batteries显示文摘A robust solid-electrolyte interphase(SEI)enabled by electrolyte additive is a promising approach to stabilize Li anode and improve Li cycling efficiency.However,the self-sacrificial nature of SEI forming additives limits their capability to stabilize Li anode for long-term cycling.Herein,we demonstrate nanocapsules made from metal–organic frameworks for sustained release of LiNO3 as surface passivation additive in commercial carbonate-based electrolyte.The nanocapsules can offer over 10 times more LiNO3 than the solubility of LiNO3.Continuous supply of LiNO3 by nanocapsules forms a nitride-rich SEI layer on Li anode and persistently remedies SEI during prolonged cycling.As a result,lifespan of thin Li anode in 50μm,which experiences drastic volume change and repeated SEI formation during cycling,has been notably improved.By pairing with an industry-level thick LiCoO2 cathode,practical Li-metal full cell demonstrates a remarkable capacity retention of 90%after 240 cycles,in contrast to fast capacity drop after 60 cycles in LiNO3 saturated electrolyte. | Qianqian Liu Yifei Xu Jianghao Wang Bo Zhao Zijian Li Hao Bin Wu | 2020 | Nano-Micro Letters2020，12，12： | 4 |
| 10 | Three dysregulated microRNAs in serum as novel biomarkers for gastric cancer screening显示文摘 | Hui Wang Lei Wang Zheng Wu Rong Sun Haifeng Jin Jifeng Ma Lili Liu Rui Ling Jun Yi Ling Wang Jiefang Bian Jianghao Chen Nanlin Li Shifang Yuan Jun Yun | 2014 | Medical Oncology2014，，12： | 4 |
| 11 | Aerodynamics and dynamic stability of micro-air-vehicle with four flapping wings in hovering flight显示文摘Recently,a novel concept of flapping Micro-Air-Vehicles(FMAVs)with four wings has been proposed,which potentially utilizes the clap-and-fling effect for lift enhancement and agile maneuvers through an adjustment of wing kinematics.However,the application of the clap-and-fling effect in the four-winged FMAVs is underexplored and the dynamic stability is still unclear.In this paper,aerodynamics and flight dynamic stability of the four-winged FMAVs are studied experimentally and numerically.Results show that the clap-and-fling effect is observed when the flapping frequency is above 18 Hz.Due to the clap-and-fling effect,the lift generation and aerodynamic efficiency are both improved,which is mainly attributed to the fling phase.Further studies show that the clap-and-fling effect becomes weaker as the wing root spacing increases and is almost absent at a wing root spacing of 1.73 chord length.In addition,a wing with an aspect ratio of 3 can increase both lift generation and efficiency due to the clap-and-fling effect.Finally,according to the dynamic stability analysis of the four-winged FMAV,the divergence speed of the lateral oscillation mode is about 4 times faster than that of the longitudinal oscillation mode.Our results can provide guidance on the design and control of four-winged FMAVs. | Cheng Cheng Jianghao Wu Yanlai Zhang Han Li Chao Zhou | 2020 | Advances in Aerodynamics2020，2，1： | 2 |
| 12 | Aerodynamic mechanisms in bio-inspired micro air vehicles:a review in the light of novel compound layouts显示文摘Modern designs of micro air vehicles(MAVs)are mostly inspired by nature's flyers,such as hummingbirds and flying insects,which results in the birth of bio-inspired MAVs.The history and recent progress of the aerodynamic mechanisms in bio-inspired MAVs are reviewed in this study,especially focused on those compound layouts using bio-inspired unsteady aerodynamic mechanisms.Several successful bio-mimicking MAVs and the unsteady high lift mechanisms in insect flight are briefly revisited.Four types of the compound layouts,i.e.the fixed/flapping-wing MAV,the flapping rotary wing MAV,the multiple-pair flapping-wing MAV,and the cycloidal rotor MAV are introduced in terms of recent findings on their aerodynamic mechanisms.In the end,future interests in the field of MAVs are suggested.The authors'review can provide solid background knowledge for both future studies on the aerodynamic mechanisms in bio-inspired MAVs and the practical design of a bio-inspired MAV. | Long Chen Yanlai Zhang Chao Zhou Jianghao Wu | 2019 | IET Cyber-Systems and Robotics2019，1，1： | 2 |
| 13 | Aerodynamic Characteristics of the Crest with Membrane Attachment on Cretaceous Pterodactyloid Nyctosaurus显示文摘Nyctosaurus 标本 KJ1 在有膜,纳入冠的假设下面被重建;所谓的头风帆冠。对头风帆冠起作用的空气动力学的力量和时刻被分析。 KJ1 可能作为产生戳的一个方法相对空气水流调整头风帆冠的角度,这被显示出(空气动力学的力量之一,过去常克服身体在前面的飞行拖)并且戳和时刻的大小能与在头风帆冠和身体的空气动力学的中心之间的手势角度和相对地点变化,这是重心。三种情形为比较被测试:有膜附件,没有膜附件的冠和头部的冠的缺席的冠。这被显示出空气动力学的特征(增加,维持并且减少戳和时刻) 将有没有膜附件,几乎为冠消失在飞行并且没有头部的冠,是不存在的。Nyctosaurus 标本 KJ1 把膜纳入了冠并且为辅助飞行控制使用了这种重建的形式,这独自从气体动力学证据被建议。 | XING Lida WU Jianghao LU Yi Lü Junchang JI Qiang | 2009 | Acta Geologica Sinica(English Edition)2009，83，1： | 2 |
| 14 | Wing Modulation and Aerodynamics of Hoverflies in Gust Perturbations显示文摘Flapping-Wing Micro-Air Vehicles are likely to suffer from airflow perturbations.They can mimic the wing modulation of insects in airflow perturbations.However,our knowledge of wing modulation of insects to airflow perturbations remains limited.Here,we subjected hoverflies to headwind and lateral gust perturbations and filmed their wing motions.Then,computational fluid dynamics was employed to estimate the effects of hoverflies’wing kinematic modulations.We also clipped off the antennae of hoverflies to test whether the wing kinematic modulations were different.Results show that hoverflies increase the mean positional angle and modulate the deviation angle to make the wing tip paths of upstroke and downstroke close to compensate for the pitch moment perturbations in the headwind gust.Hoverflies employ asymmetric responses in positional angle in the lateral gust.The stroke amplitude of the left(right)wing increases(decreases)and the mean positional angle of the left(right)wing decreases(increases)during the right lateral gust.Antennae have little effect on the wing kinematic modulations in the lateral gust.These asymmetric responses produce a roll moment,tilting the body to resist the side force generated by the gust.This is a typical helicopter model employed by hoverflies to alleviate the gust.These results provide insight into the remarkable capacity of hoverflies to contend with gusts and can also inspire the design of flapping-wing micro-air vehicles. | Yanlai Zhang Mancang Gu Jianghao Wu | 2023 | Journal of Bionic Engineering2023，20，2： | 1 |
| 15 | Hetero‑Interfaces on Cu Electrode for Enhanced Electrochemical Conversion of CO_(2)to Multi‑Carbon Products显示文摘Electrochemical CO_(2)reduction reaction(CO_(2)RR)to multi-carbon products would simultaneously reduce CO_(2)emission and produce high-value chemicals.Herein,we report Cu electrodes modified by metal–organic framework(MOF)exhibiting enhanced electrocatalytic performance to convert CO_(2) into ethylene and ethanol.The Zr-based MOF,UiO-66 would in situ transform into amorphous ZrOx nanoparticles(a-ZrO_(x)),constructing a-ZrOx/Cu hetero-interface as a dual-site catalyst.The Faradaic efficiency of multi-carbon(C2+)products for optimal UiO-66-coated Cu(0.5-UiO/Cu)electrode reaches a high value of 74%at−1.05 V versus RHE.The intrinsic activity for C2+products on 0.5-UiO/Cu electrode is about two times higher than that of Cu foil.In situ surface-enhanced Raman spectra demonstrate that UiO-66-derived a-ZrO_(x)coating can promote the stabilization of atop-bound CO^(*)intermediates on Cu surface during CO_(2)electrolysis,leading to increased CO^(*)coverage and facilitating the C–C coupling process.The present study gives new insights into tailoring the adsorption configurations of CO_(2)RR intermediate by designing dual-site electrocatalysts with hetero-interfaces. | Xiaotong Li Jianghao Wang Xiangzhou Lv Yue Yang Yifei Xu Qian Liu Hao Bin Wu | 2022 | Nano-Micro Letters2022，14，8： | 1 |
| 16 | Understanding urban China with open data显示文摘 | Xingjian Liu Yan Song Kang Wu Jianghao Wang Dong Li Ying Long | 2015 | Cities2015，，： | 1 |
| 17 | Peroxolyxotungsten-based Ionic hybrid as a highly efficient recyclable catalyst for epoxida- tion of vegetable oil with H202 显示文摘 | Wu Jianghao Jiang Pingping Qin Xiaojie | 2014 | Bull Korean Chemical Society2014，35，： | 1 |
| 18 | The DELLA-ABI4-HY5 module integrates light and gibberellin signals to regulate hypocotyl elongation显示文摘Plant growth is coordinately controlled by various environmental and hormonal signals,of which light and gibberellin(GA)signals are two critical factors with opposite effects on hypocotyl elongation.Although interactions between the light and GA signaling pathways have been studied extensively,the detailed regulatory mechanism of their direct crosstalk in hypocotyl elongation remains to be fully clarified.Previously,we reported that ABA INSENSITIVE 4(ABI4)controls hypocotyl elongation through its regulation of cellelongation-related genes,but whether it is also involved in GA signaling to promote hypocotyl elongation is unknown.In this study,we showthat promotion of hypocotyl elongation by GA is dependent on ABI4 activation.DELLAs interact directly with ABI4 and inhibit its DNA-binding activity.In turn,ABI4 combined with ELONGATED HYPOCOTYL 5(HY5),a key positive factor in light signaling,feedback regulates the expression of the GA2ox GA catabolism genes and thus modulates GA levels.Taken together,our results suggest that the DELLA-ABI4-HY5 module may serve as a molecular link that integrates GA and light signals to control hypocotyl elongation. | Haibo Xiong Dandan Lu Zhiyuan Li Jianghao Wu Xin Ning Weijun Lin Zechen Bai Canhui Zheng Yang Sun Wei Chi Lixin Zhang Xiumei Xu | 2023 | Plant Communications2023，4，5： | 0 |
| 19 | Kinematics,Deformation,and Aerodynamics of a Flexible Flapping Rotary Wing in Hovering Flight显示文摘The Flapping Rotary Wing(FRW)is a micro air vehicle wing layout coupling flapping,pitching,and rotating motions.It can gain bencfits in high lift from a fast passive rotating motion,which is tightly related to the passive pitching motion directly caused by wing flexible deformation.Therefore,flexible deformation is crucial for the wing kinematics and aerodynamic performance of an FRW.In this paper,we explored the effct of flexibility on wing kinematics and acrodynamics on the basis of a mechanical FRW model.A photogrammetric method was adopted to capture motion images according to which wing orientations and deformations were reconstructed.Corresponding acrodynamic force was computed using computational fluid dynamic method,and wing kinematics and deformations were used as simulation inputs.The experimental measurements presented the real orientation and deformation pattem of a real FRW.The wing passive deformation of a high-intensity FRW was found to be mainly caused by inertial force,and a linear positive spanwise twist was observed in the FRW.The effects of wing deformation on aerodynamic force production and the underlying mechanism were addressed.Results showed that lift augment,rotating moment enhancement,and power efficiency improvement can be achieved when a wing becomes flexible.Wing spanwise twist mainly accounts for these changes in aerodynamics,and increment in spanwise twist could further contributes to aerodynamic improvement. | Chao Zhou Jianghao Wu | 2021 | Journal of Bionic Engineering2021，18，1： | 0 |
| 20 | Correction to:Aerodynamics and dynamic stability of micro-air-vehicle with four flapping wings in hovering flight显示文摘Following publication of the original article[1],the authors identified errors in Figs.2 and 7.The correct figures are given below.Author details 1School of Transportation Science and Engineering,Beihang University,Beijing 100191,China. | Cheng Cheng Jianghao Wu Yanlai Zhang Han Li Chao Zhou | 2020 | Advances in Aerodynamics2020，2，1： | 0 |
您所在的机构暂未开通此部分的功能，请联系管理员