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Designing a Biomimetic Ornithopter Capable of Sustained and Controlled Flight

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Journal of Bionic Engineering 2008年第1期5卷 39-47页

作者： Joon hyuk park Kwang-Joon Yoon Department of Aerospace Information System and Artificial Muscle Research Center Konkuk University Seoul 143-701 Korea

We describe the design of four ornithopters ranging in wing span from 10 cm to 40 cm, and in weight from 5 g to 45 g. The controllability and power supply are two major considerations, so we compare the efficiency and characteristics between different types of subsystems such as gearbox and tail shape. Our current omithopter is radio-controlled with inbuilt visual sensing and capable of takeoff and landing. We also concentrate on its wing efficiency based on design inspired by a real insect wing and consider that aspects of insect flight such as delayed stall and wake capture are essential at such small size. Most importantly, the advance ratio, controlled either by enlarging the wing beat amplitude or raising the wing beat frequency, is the most significant factor in an ornithopter which mimics an insect.

关键词： biomimetic ornithopter flapping wing unsteady state low Reynolds number

The Soft X-ray Imager(SXI)on the SMILE Mission

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Earth and Planetary Physics 2024年第1期8卷 5-14页

作者： S.Sembay A.L.Alme D.Agnolon T.Arnold A.Beardmore A.Belén Balado Margeli C.Bicknell C.Bouldin g.Branduardi-Raymont T.Crawford J.P.Breuer T.Buggey g.Butcher R.Canchal J.A.Carter A.Cheney Y.Collado-Vega H.Connor T.Crawford N.Eaton C.Feldman C.Forsyth T.Frantzen g.galgóczi J.garcia g.Y.genov C.gordillo H-P.gröbelbauer M.guedel Y.guo M.Hailey D.Hall R.Hampson J.Hasiba O.Hetherington A.Holland S-Y.Hsieh M.W.J.Hubbard H.Jeszenszky M.Jones T.Kennedy K.Koch-Mehrin S.Kögl S.Krucker K.D.Kuntz C.Lakin g.Laky O.Lylund A.Martindale J.Miguel Mas Hesse R.Nakamura K.Oksavik N.Østgaard H.Ottacher R.Ottensamer C.Pagani S.Parsons P.Patel J.Pearson g.Peikert F.S.Porter T.Pouliantis B.H.Qureshi W.Raab g.Randal A.M.Read N.M.M.Roque M.E.Rostad C.Runciman S.Sachdev A.Samsonov M.Soman D.Sibeck S.Smit J.Søndergaard R.Speight S.Stavland M.Steller TianRan Sun J.Thornhill W.Thomas K.Ullaland B.Walsh D.Walton C.Wang S.Yang School of Physics and Astronomy University of LeicesterLeicesterLE17RHUK Space park Leicester University of LeicesterLeicesterLE17RHUK Mullard Space Science Laboratory University College LondonDorkingRH56NTUK Centre for Electronic Imaging Open UniversityMilton KeynesMK76 AAUK Birkeland Centre for Space Science Department of Physics and TechnologyUniv.of BergenN-5007 BergenNorway University of Vienna A-1010 ViennaAustria Space Research Institute Austrian Academy of SciencesA-8042 GrazAustria National Institute of Aerospace Technology MadridSpain ESTEC European Space Agency2201 AZ NoordwijkNetherlands State Key Laboratory of Space Weather National Space Science CentreBeijing 100190China University of Applied Sciences and Arts Northwestern Switzerland CH-5210 WindischSwitzerland Koegl Space gmbH CH-8157 DielsdorfSwitzerland Space Acoustics gmbH CH-8157 DielsdorfSwitzerland Zurich University of Applied Sciences 8400 WinterhurSwitzerland genov Solutions N-5172 LoddefjordNorway STM Engineering N-5165 LaksevagNorway John Hopkins University Applied Physics Laboratory MD 20723USA NASA/goddard Space Flight Centre MD 20771USA Center for Space Physics Boston UniversityBostonMA 02215USA Department of Theoretical Physics and Astrophysics Masaryk University60177 BrnoCzech Republic Institute of Physics E¨otvo¨s Lor´and University1053 BudapestHungary Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100045China Centro de Astrobiologia(CAB) CSIC-INTAMadridSpain

The Soft X-ray Imager(SXI)is part of the scientific payload of the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)*** is a joint science mission between the European Space Agency(ESA)and the Chinese Academy of Sciences(CAS)and is due for launch in *** is a compact X-ray telescope with a wide field-of-view(FOV)capable of encompassing large portions of Earth’s magnetosphere from the vantage point of the SMILE *** is sensitive to the soft X-rays produced by the Solar Wind Charge eXchange(SWCX)process produced when heavy ions of solar wind origin interact with neutral particles in Earth’s *** provides a mechanism for boundary detection within the magnetosphere,such as the position of Earth’s magnetopause,because the solar wind heavy ions have a very low density in regions of closed magnetic field *** sensitivity of the SXI is such that it can potentially track movements of the magnetopause on timescales of a few minutes and the orbit of SMILE will enable such movements to be tracked for segments lasting many *** is led by the University of Leicester in the United Kingdom(UK)with collaborating organisations on hardware,software and science support within the UK,Europe,China and the United States.

关键词： Soft X-ray Imaging micropore optics large area CCD

Inverse Kinematics Analysis and COg Trajectory Planning Algorithms for Stable Walking of a Quadruped Robot with Redundant DOFs

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Journal of Bionic Engineering 2018年第4期15卷 610-622页

作者： hyunkyoo park Bokeon Kwak Joonbum Bae Lg-electronics Seou108592 Republic of Korea Department of Mechanical Engineering Ulsan National Institute of Science and Technology Ulsan 44919 Republic of Korea

This paper presents a new Center of gravity （COg） trajectory planning algorithm for a quadruped robot with redundant Degrees of Freedom （DOFs）. Each leg has 7 DOFs, which allow the robot to exploit its kinematic redundancy for various locomotion and manipu- lation tasks. Also, the robot can suitably adapt to different environment （e.g., passing through a narrow gap） by simply changing the body posture. However, the robot has significant COg movement during the leg swinging phase due to the heavy leg weights; the weight of all the four legs takes up 80% of the robot＇s total weight. To achieve stable walking in the presence of undesired COg movements, a new COg trajectory planning algorithm was proposed by using a combined Jacobian of COg and centroid of a support polygon including a foot contact constraint. Additionally, the inverse kinematics of each leg was solved by modified improved Jacobian pseudoinverse （mIJP） algorithm. The mIJP algorithm could generate desired trajectories for the joints even when the robot＇s leg is in a singular posture. Owing to these proposed methods, the robot was able to perform various modes of locomotion both in simulations and experiments with improved stability.

关键词： legged robot redundant degree-of-freedoms stable walking center-of-gravity planning

Design and Demonstration of a Locust-Like Jumping Mechanism for Small-Scale Robots

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Journal of Bionic Engineering 2012年第3期9卷 271-281页

作者： Quoc-Viet Nguyen Hoon Cheol park Department of Advanced Technology Fusion Konkuk University Seoul 143-701 Republic of Korea

A jumping mechanism can be an efficient mode of motion for small robots to overcome large obstacles on the ground and rough terrain. In this paper, we present a 7 g prototype of locust-inspired jumping mechanism that uses springs, wire, reduction gears, and a motor as the actuation components. The leg structure and muscles of a locust or grasshopper were mimicked using springs and wire, springs for passive extensor muscles, and a wire as a flexor muscle. A small motor was used to slowly charge the spring through a lever and gear system, and a cam with a special profile was used as a clicking mechanism for quick release of elastic energy stored in the springs to create a sudden kick for a quick jump. Performance analysis and experiments were conducted for comparison and performance estimation of the jumping mechanism prototype. Our prototype could produce standing jumps over obstacles that were about 14 times its own size （approximate to 71 cm） and a jumping distance of 20 times its own size （approximate to 100 cm）.

关键词： biomimetics locust jumping mechanism passive tibia extensor muscle

Rational design and synthesis of hierarchically structured SnO2 microspheres assembled from hollow porous nanoplates as superior anode materials for lithium-ion batteries

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Nano Research 2018年第3期11卷 1301-1312页

作者： gi Dae park Yun Chan Kang Department of Materials Science and Engineering Korea University Anam-Dong Seongbuk-Gu Seoul 136-713 Republic of Korea

Herein, hierarchically structured SnO2 microspheres are designed and synthesized as an efficient anode material for lithium-ion batteries using hollow SnO2 nanoplates. Three-dimensionally ordered macroporous （3-DOM） SnOx-C microspheres synthesized by spray pyrolysis are transformed into hierarchically structured SnO2 microspheres by a two-step post-treatment process. Sulfidation produces hierarchically structured SnS-SnS2-C microspheres comprising tin sulfide nanoplate and carbon building blocks. A subsequent oxidation process produces SnO2 microspheres from hollow SnO2 nanoplate building blocks, which are formed by Kirkendall diffusion. The discharge capacity of the hierarchically structured SnO2 microspheres at a current density of 5 Ag^-1 for the 600th cycle is 404 mA·h·g^-1. The hierarchically structured SnO2 microspheres have reversible discharge capacities of 609 and 158 mA·h·g^-1 at current densities of 0.5 and 30 Ag^-1, respectively. The ultrafine nanosheets contain empty voids that allow excellent lithium-ion storage performance, even at high current densities.

关键词： Kirkendall diffusion nanoplate tin oxide lithium-ion batter spray pyrolysis

Novel in-capsule synthesis of metal-organic framework for innovative carbon dioxide capture system

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green Energy & Environment 2023年第3期8卷 767-774页

作者： Wei Yu Ming gao guanhe Rim Tony g.Feric Mark L.Rivers Ammar Alahmed Aqil Jamal Ah-hyung Alissa park State Key Laboratory of Clean Energy Utilization Zhejiang UniversityHangzhou310027China Lenfest Center for Sustainable Energy The Earth InstituteColumbia University918 S.W.Mudd HallMail Code 4711500 W 120th St.New YorkNY10027USA Department of Earth and Environmental Engineering 918 S.W.Mudd HallMail Code 4711500 W 120th St.New YorkNY10027USA Department of Chemical Engineering Columbia UniversityNew YorkNY10027USA University of Chicago ChicagoIL60637USA Research and Development Center Saudi AramcoDhahran31311Saudi Arabia

Metal-Organic Frameworks(MOFs)have been developed as solid sorbents for CO_(2) capture applications and their properties can be controlled by tuning the chemical blocks of their crystalline units.A number of MOFs(e.g.,HKUST-1)have been developed but the question remains how to deploy them for gas-solid ***,the direct use of MOFs as nanocrystals would lead to serious problems and ***,for the first time,we report a novel MOF-based hybrid sorbent that is produced via an innovative in-situ microencapsulated *** a custom-made double capillary microfluidic assembly,double emulsions of the MOF precursor solutions and UV-curable silicone shell fluid are ***,HKUST-1 MOF is successfully synthesized within the droplets enclosed in the gas permeable *** developed MOF-bearing microcapsules uniquely allow the deployment of functional nanocrystals without the challenge of handling ultrafine particles,and further,can selectively reject undesired compounds to protect encapsulated MOFs.

关键词： Encapsulation Metal-Organic Frameworks(MOFs) Carbon capture In-situ microencapsulated synthesis

Antiproliferative and apoptosis-inducing potential of 3β-hydroxy-△5-steroidal congeners purified from the soft coral Dendronephthya putteri

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Journal of Oceanology and Limnology 2019年第4期37卷 1382-1392页

作者： Thilina U. JAYAWARDENA Won Woo LEE I. P. Shanura FERNANDO K. K. Asanka SANJEEWA Lei WANg Tee gee LEE young Jin park Chang-ik KO you-Jin JEON Department of Marine Life Sciences Jeju National University Jeju 690-756 Republic of Korea Department of Hotel Cooking Nutrition Jeonnam Provincial College Jeollanam-do Republic of Korea Department of Family Medicine College of Medicine Dong-A University Busan 602-715 Republic of Korea Choung Ryong Fisheries Co. Ltd. 7825 Iljudong-ro Namwon-eup Seogwipo-si Jeju-do Republic of Korea

The exploration and identification of antiproliferative phytochemicals have received increased attention in medicinal chemistry. In particular, research focused on the toxicology of marine natural products has increased in recent years. Terpenoids, among many secondary metabolites, have been demonstrated to act as effective anticancer agents. Soft corals, a group of marine invertebrates, produce a variety of terpenoids with biofunctional properties. The current study presents the extraction, purification, and identification of sterol congeners from the soft coral Dendronephthya putteri. The method involves 50% chloroform-methanol extraction, polar column fractionation, and analysis through gC-MSn. Dose-dependent antiproliferative activity was observed within the sterol-rich fraction (DPCMH 2-4), which consisted of 3β-hydroxy-Δ5-steroidal congeners. This fraction inhibited the growth of HL-60 and MCF-7 cells with IC50 values of 25.27±1.43 and 22.81±0.15 μg/mL, respectively. Apoptotic body formation, DNA damage, cell cycle arrest, and apoptotic cell signaling pathway activation were also observed, reinforcing the dose-dependent antiproliferative and apoptosis-inducing activity of 3β-hydroxy-Δ5-steroidal congeners. To our knowledge, this is the first report of anticancer agent identification from the soft coral D. putteri. Based on the observations, these steroidal congeners are promising candidates for the development of anticancer drugs.

关键词： Dendronephthya putteri soft coral antiproliferative agent HL-60 MCF-7 apoptosis steroidal congeners

Preparation of Li[Ni_(1/3)Co_(1/3)Mn_(1/3)]O_2 powders for cathode material in secondary battery by solid-state method

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Rare Metals 2006年第Z2期25卷 184-188页

作者： park Sook Hee KANg Chan Hyoung Department of Advanced Materials Engineering Korea Polytechnic University Shihung Kyonggi-do 429-793 Korea

Employing Li2CO3, NiO, Co3O4, and MnCO3 powders as starting materials, Li[Ni1/3Co1/3Mn1/3]O2 was synthesized by solid-state reaction method. Various grinding aids were applied during milling in order to optimize the synthesis process. After successive heat treatments at 650 and 950 ℃, the prepared powders were characterized by X-ray diffraction (XRD) analysis, scanning electron microscopy, and transmission electron microscopy. The powders prepared by adding salt (NaCl) as grinding aid exhibit a clear R3m layer structure. The powders by other grinding aids like heptane show some impurity peaks in the XRD pattern. The former powders show a uniform particle size distribution of less than 1 μm average size while the latter shows a wide distribution ranging from 1 to 10 μm. Energy dispersive X-ray (EDX) analysiss show that the ratio of Ni, Co, and Mn content in the powder is approximately 1/3, 1/3, and 1/3, respecively. The EDX data indicate no incorporation of sodium or chlorine into the powders. Charge-discharge tests gave an initial discharge capacity of 160 mAh·g-1 for the powders with NaCl addition while 70 mAh·g-1 for the powders with heptane.

关键词： lithium ion battery cathode materials layered structure solid-state method discharge density

Immune stimulatory activity of BRP-4,an acidic polysaccharide from an edible plant,Basella rubra L.

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Asian Pacific Journal of Tropical Medicine 2014年第11期7卷 849-853页

作者： Hye-Jin park Department of Food Science and Biotechnology Gachon University

Objective:To evaluated the immunomodulatory effect of BRP-4,an acidic polysaccharide from Basella rubra(***) L on the macrophage ***:Phagocytic activity was determined by the ingestion of Latex Beads-Rabbit IgC-FITC using the fluorescent microscopy and flow cytometry analysis and nitric oxide production was measured using griess reaction ***:An enhanced production of NO was observed at 10 and 100 μg/mL of *** phagocytic activity of macrophage was enhanced in BRP-4 treated RAW264.7 ***-4combined with concanavalin A(Con A) provided obvious promotion and strengthening of the proliferation of the ***:BRP-4,polysaccharide isolated from ***,is suggested to activate macrophage function and stimulate splenocyte *** strong immunomodulatory activity of BRP-4 confirmed its good potential as an immunotherapeutic adjuvant.

关键词： BRP-4 Phagocytic activity Macrophage Splenocyte proliferation Immune stimunlatory