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Development of a Biomimetic Quadruped Robot

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Journal of Bionic Engineering 2007年第4期4卷 193-199页

作者： Thanhtam ho Sunghac choi Sangyoon Lee Department of Mechanical Design and Production Engineering Konkuk University Seoul 143-701 Korea

This paper presents the design and prototype of a small quadruped robot whose walking motion is realized by two piezocomposite actuators. In the design, biomimetic ideas are employed to obtain the agility of motions and sustainability of a heavy load. The design of the robot legs is inspired by the leg configuration of insects, two joints （hip and knee） of the leg enable two basic motions, lifting and stepping. The robot frame is designed to have a slope relative to the horizontal plane, which makes the robot move forward. In addition, the bounding locomotion of quadruped animals is implemented in the robot. Experiments show that the robot can carry an additional load of about 100 g and run with a fairly high velocity. The quadruped prototype can be an important step towards the goal of building an autonomous mobile robot actuated by piezocomposite actuators.

关键词： quadruped robot piezocomposite actuator bounding locomotion

Decomposition of Nitrogen Trifluoride Using Low Power Arc Plasma

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Plasma Science and Technology 2013年第9期15卷 923-927页

作者： jee-Hun KO Sooseok choi Hyun-Woo PARK Dong-Wha PARK Department of Chemical Engineering and Regional Innovation Center for Environmental Technology of Thermal Plasma (RIC-ETTP)INHA University253 Yonghyun-dongNam-guIncheon 402-751Republic of Korea Department of Environmental Chemistry and Engineering Tokyo Institute of Technology 4259-G1-22Nagatsuta-choMidori-kuYokohama 226-8502Japan

The low power arc plasma is characterized by extremely high enthalpy and temper- ature and it is easy to generate and control, and thus thermal decomposition process based on the plasma torch is receiving a great attention for decomposing non-degradable greenhouse gases. In order to elevate the economic feasibility, the effects of input power, waste gas flow rate and additive gases on the destruction and removal efficiency （DRE） of NF3 are examined. Specific energy density （SED） deceases as the flow rate increases, and accordingly, the DRE is reduced. The DRE is basically determined by the specific energy density. The highest DRE of NF3 was 97% for the waste gas flow rate of 100 L/min at a low input power level of 2 kW with the help of hydrogen additional gas. The inlet and outlet concentration of NF3 was analyzed using Fourier transform infrared spectroscopy （FT-IR） for DRE of NF3 evaluation. As a result, large amount of NF3 can be efficiently decomposed by low power arc plasma systems.

关键词： arc plasma decomposition nitrogen trifluoride

Optimal design of auxiliary-teeth to solve circulation current reduction of permanent magnet linear synchronous motor

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Journal of Central South University 2011年第3期18卷 690-696页

作者： JANG Ki-bong KIM jee-hyun AN ho-jin KIM Gyu-tak School of Mechatronics Changwon National University

A discontinuity of magnetic circuits according to the end effect is generated in the permanent magnet linear synchronous motor （PMLSM）. Due to the unbalanced back electro-motive force （EMF） and impedance produced, unbalanced current is generated. The cireulatin8 current, which is caused by a decrease in the thrust, is generated by the unbalanced current. The optimal design of auxiliary-teeth at the end of the mover was carried out to solve the unbalance of phase by using design of experiment （DOE）, and compared with the basic model through finite element analysis （FEA）. As a result, the auxiliary-teeth model compensates for the decrease of thrust caused by the unbalanced phase. Also, this model is proven to reduce the detent force by the vibration and noise of the PMLSM and copper loss caused by the circulating current.

关键词： permanent magnet linear synchronous motor auxiliary-teeth circulation current end effect thrust reduction

Influence of the wastewater composition on denitrification and biological P-removal in the S-DN-P process: (c) Dissolved and undissolved substrates

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Journal of Environmental Sciences 2009年第8期21卷 1074-1079页

作者： Hee-Jeong choi Chul-ho choi Seung-Mok Lee Diwakar Tiwari Department of Environmental Engineering Kwandong University Department of Chemistry School of Physical Sciences Mizoram University

The denitdfication and P-removal in the sorption-denitrification-P-removal （S-DN-P） process were carded out under various wastewater compositions. It is noted that P-removal largely depends on the wastewater composition as well to the quantity of the substrates present in wastewater fraction. Three different wastewater fractions are obtained as： raw wastewater, dissolved wastewater （obtained with filtration using 0.45 μm filter）, and undissolved wastewater （i.e., infiltrate obtained by above filtration）. The ratio of P-release/CODtotal-consumption clearly inferred that undissolved wastewater possess very low value i.e., 0.0008 followed by raw wastewater 0.008 and dissolved wastewater 0.03. When this ratio was nearby 0.01, enhanced P-removal was observed. Moreover, the ratio of P-uptake to NO3^--N decomposition for raw wastewater was two times for dissolved wastewater. Interestingly, it was observed that the P-removal and denitrification depend not only on the dissolved substrates but also the undissolved substrates present in the wastewater. The result of the P-removal obtained with this S-DN-P process did not show a big difference of 36%, 34% and 30%, respectively, for raw, dissolved and undissolved wastewater.

关键词： denitrification polyhydroxybutyrate sequencing batch biofilm reactor sorption denitrification P-removals

Evaluation of the safety of hair essence containing 0.05% purified bee venom on the skin and eyes of rabbits

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Journal of Traditional Chinese Medicine 2020年第1期40卷 67-72页

作者： Mi Kyung Lim Eun Hye Han Sang ho Lee jee Hee Kim R&D Center KoreaeundanGyeonggi-do 13207Republic of Korea

OBJECTIVE:To investigate the safety of hair essence containing 0.05%purified bee venom(HE-PBV)on the skin and eyes of New Zealand White ***:HE-PBV which contained 0.05%PBV,purified water,and glycerin,was used as the test *** skin-irritation test(SIT)and eye-irritation test(EIT)were conducted according to the Draize *** the SIT,HE-PBV(0.5 m L)dropped gauze was attached both intact and abraded skin for 24 *** other side of the skin was used as *** 24 and 72 h,the treatment site was observed and scored according to evaluation criteria for skin *** the EIT,the rabbits were divided into two groups:eye-washed(three rabbits)and non-eye-washed(six rabbits).HE-PBV(0.1 m L)was squirted into the right eye of *** left eye was untreated and used as a ***,20-30-s later,the eyes of rabbits in the eye-washed group were washed with^50 m L of physiologic(0.9%)salt ***,1,2,3,4 and 7 d after the start of the EIT,the eyes and behavior of the rabbits were *** degree of eye irritation elicited by HE-PBV was determined in three steps and then the criteria of the classification of eye-irritation ***:The SIT revealed erythema and edema at the site of HE-PBV *** 72 h,the body weight of rabbits was reduced slightly,but other symptoms(except erythema and edema)were not *** Primary Irritation Index score was0.6,and HE-PBV was deemed to be a slight *** EIT did not show mortality or body-weight fluctuation,but hyperemic conjunctiva and eyelid closure were noted after HE-PBV *** for these results,the score for the ophthalmic response on days 1,2,3,4 and 7 was 0,and HE-PBV was deemed to be a ***:These data suggest that HE-PBV did not elicit eye irritation,but was a slight irritant to the skin of rabbits;the latter slight would have been due to the excipients used in manufacture of the hair essence because PBV has been shown to be safe.

关键词： Alopecia Bee Venoms Hair essence Skin irritancy tests Eye irritancy tests Complementary therapies

Aerosol-assisted rapid synthesis of SnS-C composite microspheres as anode material for Na-ion batteries

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Nano Research 2015年第5期8卷 1595-1603页

作者： Seung ho choi Yun Chan Kang Department of Materials Science and Engineering Korea University Anam-Dong Seongbuk-Gu Seou1136-713 Republic of Korea

SnS-C composite powders were prepared through one-pot spray pyrolysis for use as anode materials for Na-ion batteries. C microspheres with uniformly attached cubic-like SnS nanocrystals, which have an amorphous C coating layer, were formed at a preparation temperature of 900 ℃. The initial discharge capacities of the bare SnS and SnS-C composite powders at a current density of 500 mA·g^-1 were 695 and 740 mA·h·g^-1, respectively. The discharge capacities after 50 cycles and the capacity retentions measured from the second cycle of the bare SnS and SnS-C composite powders were 25 and 433 mA.h.g-1 and 5 and 89%, respectively. The prepared SnS-C composite powders with high reversible capacities and good cycle performance can be used as Na-ion battery anode materials.

关键词： tin sulfide anode material carbon composite sodium battery energy storage

ON THE ASYMPTOTIC DYNAMICS OF THE VLASOV-YUKAWA-BOLTZMANN SYSTEM NEAR VACUUM

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Acta Mathematica Scientia 2015年第4期35卷 887-905页

作者： Sun-ho choi Seung-Yeal HA Department of Mathematical Sciences KAIST Department of Mathematical Sciences and Research Institute of Mathematics Seoul National University

In this pape,~ we study uniform L1-stability and asymptotic completeness of the Vlasov-Yukawa-Boltzmann （V-Y-B） system. For a sufficiently small rand smooth initial data, we show that classical solutions exist globally and satisfy dispersion estimates, uniform L1-stability with respect to initial data and scattering type estimate. We show that the short range nature of interactions due to the Yukawa potential enables us to construct robust Lyapunov type functional to derive scattering states. In the zero mass limit of force carrier particles, we also show that the classical solutions to the V-Y-B system converge to that of the Vlasov-Poisson-Boltzmann （V-P-B） system in any finite time interval

关键词： asymptotic completeness collision operator the Vlasov-Yukawa-Boltzmannsystem uniform L1-stability

Characteristics of Atmospheric Circulation Associated with Cold Surge Occurrences in East Asia:A Case Study During 2005/06 Winter

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Advances in Atmospheric Sciences 2008年第5期25卷 791-804页

作者： Tae-Won PARK jee-hoon JEONG Chang-hoi ho Seong-Joong KIM School of Earth and Environmental Sciences Seoul National University Seoul Korea Department of Earth Sciences University of Gothenburg Gothenburg Sweden Korea Polar Research Institute Incheon Korea

The characteristics of the upper-level circulation and thermodynamical properties for the period when two distinct cold surges broke out over East Asia during the 2005/06 winter are investigated. From early December 2005 to early January 2006, exceptionally cold weather lasted for approximately one month due to two successive cold surges that took place on 2 December 2005 and 2 January 2006, respectively. This study reveals that both involve the upper-tropospheric circulation, which induces the amplification and expansion of the surface Siberian high toward East Asia, but arose from different causes： the former is caused by the upper-level blocking originated from the North Pacific and the latter is caused by the upper-level wave train across the Eurasian Continent. In particular, it is suggested that the lower-tropospheric anomalous wind caused by upper-level circulation anomalies and a steep meridional temperature gradient amplified by phase-locked annual cycle combined to induce very strong cold advection in East Asia, which resulted in exceptionally cold weather that lasted for several weeks. The present results emphasize that the characteristics of the upper-tropospheric circulation can be considered as important precursors to cold surge occurrences in East Asia.

关键词： cold surge Siberian high East Asia East Asian winter monsoon upper-tropospheric circulation

Development of vehicle-recognition method on water surfaces using LiDAR data:SPD^(2)(spherically stratified point projection with diameter and distance)

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Defence Technology（防务技术） 2024年第6期36卷 95-104页

作者： Eon-ho Lee Hyeon Jun Jeon Jinwoo choi Hyun-Taek choi Sejin Lee The Department of Mechanical Engineering Kongju National University1223-24 Cheonan-daeroCheonan 31080Republic of Korea Ocean System Engineering Research Division Korea Research Institute of Ships and Ocean Engineering(KRISO)Daejeon 34103Republic of Korea The Division of Mechanical&Automotive Engineering Kongju National University1223-24 Cheonan-daeroCheonan 31080Republic of Korea

Swarm robot systems are an important application of autonomous unmanned surface vehicles on water *** monitoring natural environments and conducting security activities within a certain range using a surface vehicle,the swarm robot system is more efficient than the operation of a single object as the former can reduce cost and save *** is necessary to detect adjacent surface obstacles robustly to operate a cluster of unmanned surface *** this purpose,a LiDAR(light detection and ranging)sensor is used as it can simultaneously obtain 3D information for all directions,relatively robustly and accurately,irrespective of the surrounding environmental *** the GPS(global-positioning-system)error range exists,obtaining measurements of the surface-vessel position can still ensure stability during platoon *** this study,a three-layer convolutional neural network is applied to classify types of surface *** aim of this approach is to redefine the sparse 3D point cloud data as 2D image data with a connotative meaning and subsequently utilize this transformed data for object classification ***,we have proposed a descriptor that converts the 3D point cloud data into 2D image *** use this descriptor effectively,it is necessary to perform a clustering operation that separates the point clouds for each *** developed voxel-based clustering for the point cloud ***,using the descriptor,3D point cloud data can be converted into a 2D feature image,and the converted 2D image is provided as an input value to the *** intend to verify the validity of the proposed 3D point cloud feature descriptor by using experimental data in the ***,we explore the feasibility of real-time object classification within this framework.

关键词： Object classification Clustering 3D point cloud data LiDAR(light detection and ranging) Surface vehicle