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Effect of Isothermal Annealing on Nano Ti-Carbides Precipitation

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Journal of Iron and Steel Research(International) 2011年第S1期18卷 287-289页

作者： cheol-ho park Woo-jin Kim nam-hyun Kang Hyung-hyup Do Kyung-Mox Cho Department of Materials Science and Engineering Pusan National UniversityBusan 609-735Korea Technical Research Laboratories Hyundai steelsDangjinChungnam 343-711Korea

Transmission electron microscopy was used to investigate the effect of isothermal holding temperature and time on the nano Ti-precipitates.A holding temperature was varied systematically from 400℃ to 1200℃.The isothermal holding was continued for 30s,300s and 900s,*** carbides of (Ti,Nb)C were precipitated significantly at 900℃.The size of carbides was approximately 10nm at 30s holding and increased to 20～30nm at 900s *** holding at 1000℃ showed the increased amount of carbides larger than *** 800℃,nano (Ti,Nb)C was not observed at 30s and it was examined at *** size of nano (Ti,Nb)C was smaller than that of 900℃.As the isothermal temperature decreased to 700 ℃,the nano (Ti,Nb)C was only seen at 900s holding and the size of carbides was smaller than *** (Ti,Nb)C was disappeared at isothermal holding below 600℃.The kinetics of nano (Ti,Nb)C precipitation were studied as a function of isothermal holding temperature and time,respectively,using the precipitate growth equations.

关键词： Ti carbide hot rolled steel hole expansion ratio isothermal holding nano precipitates

Simulation of wind-induced near-inertial oscillations in a mixed layer near the east coast of Korea in the East/Japan Sea

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Acta Oceanologica Sinica 2013年第9期32卷 11-20页

作者： nam SungHyun park Young-Gyu Naval Systems Development Center Agency for Defense Development Ocean Circulation and Climate Research Division Korea Institute of Ocean Science and Technology

Using a simple damped slab model, it was possible to show that a local wind induced 88% （15 of 17） of the near-inertial oscillations （NIO） observed in the mixed layer near the east coast of Korea from 1999 to 2004. The model, however, overestimated the energy level in about two-thirds of the simulated cases, because the slab model was forced with winds whose characteristic period was shorter than the damping time scale of the model at 1.5 d. At the observation site, due to typhoons and orographic effects, high-frequency wind forcing is quite common, as is the overestimation of the energy level in the slab model results. In short, a simple slab model with a damping time-scale of about 1.5 d would be enough to show that the local wind was the main energy source of the near-inertial energy in this area, but the model could not be used to accurately estimate the amount of the work done by the wind to the mixed layer.

关键词： near-inertial oscillations near-inertial waves slab model high-frequency wind forcing eastcoast of Korea

Stable Vertical Takeoff of an Insect-Mimicking Flapping-Wing System Without Guide Implementing Inherent Pitching Stability

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Journal of Bionic Engineering 2012年第4期9卷 391-401页

作者： Hoang Vu Phan Quoc Viet Nguyen Quang Tri Truong Tien Van Truong Hoon cheol park nam Seo Goo Doyoung Byun Min Jun Kim Department of Advanced Technology Fusion Konkuk University Seoul 143-701 Korea Department of Aerospace Engineering Konkuk University Seoul 143-701 Korea Department of Mechanical Engineering Sungkyunkwan University Seoul 143-701 Korea Department of Mechanical Engineering and Mechanics Drexel University Philadelphia USA

We briefly summarized how to design and fabricate an insect-mimicking flapping-wing system and demonstrate how to implement inherent pitching stability for stable vertical takeoff. The effect of relative locations of the Center of Gravity （CG） and the mean Aerodynamic Center （AC） on vertical flight was theoretically examined through static force balance considera- tion. We conducted a series of vertical takeoff tests in which the location of the mean AC was determined using an unsteady Blade Element Theory （BET） previously developed by the authors. Sequential images were captured during the takeoff tests using a high-speed camera. The results demonstrated that inherent pitching stability for vertical takeoff can be achieved by controlling the relative position between the CG and the mean AC of the flapping system.

关键词： beetle flapping-wing system insect-mimicking insect flight inherent pitching stability vertical takeoff

Thrust Analysis of a Fish Robot Actuated by Piezoceramic Composite Actuators

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Journal of Bionic Engineering 2011年第2期8卷 158-164页

作者： Quang Sang Nguyen Hoon cheol park Doyoung Byun Biomimetics and bltelligent Microsystems Laboratory Department of Advanced Technology Fusion Konkuk University Seoul 143-701 South Korea Department of Advanced Technology Fusion Konkuk University Seoul 143-701 South Korea Department of Aerospace Engineering Konkuk University Seoul 143-701 South Korea

In this work, a three-dimensional （3D） Computational Fluid Dynamics （CFD） model was built to simulate the tail fin motion of a fish robot actuated by a piezoceramic composite actuator, and to determine the maximum thrust tail-beat frequency. A simulation of the tail fin at a tail-beat frequency was performed to confirm measured thrust data from a previous study. The computed and measured thrusts were in good agreement. A series of thrust simulations were conducted for various tail-beat frequencies to confirm the maximum thrust frequency that was obtained from thrust measurements in the previous study. The largest thrust was calculated at a tail-beat frequency of 3.7 Hz and vortices around the tail were fully separated. The calculated maximum thrust tail-beat frequency was in good agreement with the measured frequency. Flow characteristics during tail fin motion were examined to explain why the largest thrust occurred at this particular tail-beat frequency.

关键词： fish robot CFD LIPCA thrust measurement thrust analysis composite actuator vortex shedding

CORE:Common Region Extension Based Multiple Protein Structure Alignment for Producing Multiple Solution

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Journal of Computer Science & Technology 2013年第4期28卷 647-656页

作者： Woo-cheol Kim Sanghyun park Jung-Im Won College of Information Sciences and Technology The Pennsylvania State University University Park Department of Computer Science Yonsei University Research Center of Information and Electronic Engineering Hallym University Chuncheon

Over the past several decades, biologists have conducted numerous studies examining both general and specific functions of proteins. Generally, if similarities in either the structure or sequence of amino acids exist for two proteins, then a common biological function is expected. Protein function is determined primarily based on the structure rather than the sequence of amino acids. The algorithm for protein structure alignment is an essential tool for the research. The quality of the algorithm depends on the quality of the similarity measure that is used, and the similarity measure is an objective function used to determine the best alignment because of their individual strength and weakness However, none of existing similarity measures became golden standard They require excessive filtering to find a single alignment. In this paper, we introduce a new strategy that finds not a single alignment, but multiple alignments with different lengths. This method has obvious benefits of high quality alignment. However, this novel method leads to a new problem that the running time for this method is considerably longer than that for methods that find only a single alignment. To address this problem~ we propose algorithms that can locate a common region （CORE） of multiple alignment candidates, and can then extend the CORE into multiple alignments. Because the CORE can be defined from a final alignment, we introduce CORE＊ that is similar to CORE and propose an algorithm to identify the CORE＊. By adopting CORE＊ and dynamic programming, our proposed method produces multiple alignments of various lengths with higher accuracy than previous methods. In the experiments, the alignments identified by our algorithm are longer than those obtained by TM-align by 17% and 15.48%, on average, when the comparison is conducted at the level of super-family and fold, respectively.

关键词： structure alignment similarity search protein structure

Cecal duplication cyst in an infant presenting as shock:A case report

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世界临床病例杂志 2023年第28期11卷 6931-6937页

作者： Seung Mo Kim Sun Hyang Lee Ga Young park Sung Shin Kim cheol Gu Lee Soo Ji Jin Department of Pediatrics Soonchunhyang University Bucheon HospitalSoochunhyang University College of MedicineBucheon 14584Gyeonggi-doSouth Korea Department of General Surgery Soonchunhyang University Bucheon HospitalSoonchunhyang University College of MedicineBucheon 14584GyeongGi-DoSouth Korea Department of Pathology Soonchunhyang University Bucheon HospitalSoonchunhyang University College of MedicineBucheon 14584GyeongGi-DoSouth Korea

BACKGROUND Although intestinal obstruction is one of the most common surgical emergencies in an infant,it is difficult to diagnose neonatal enteric duplication cysts(EDC)preoperatively owing to their rarity as a cause of intestinal *** describe a case report of a neonatal EDC presenting intestinal obstruction and *** SUMMARY A 32-d-old male infant with a prenatal sonographic finding of bladder distension was admitted to our hospital for a severely distended abdomen,fever,and *** first diagnostic hypothesis was septic shock and intestinal *** patient’s symptoms worsened;following an emergency surgical exploratory laparotomy and histopathological findings,the final diagnosis of cecal duplication cyst was *** patient’s postoperative course was uneventful,and on the fifth postoperative day,oral feeding *** days later,the patient was discharged from the *** Although EDC located in the cecum is exceptional,it should be considered when evaluating suspected intestinal obstruction and shock.

关键词： Duplication cyst Cecum Intestinal obstruction Infant Shock Case report

T cell epitopes in SARS-CoV-2 proteins are substantially conserved in the Omicron variant

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Cellular & Molecular Immunology 2022年第3期19卷 447-448页

作者： Seong Jin Choi Dong-Uk Kim Ji Yun Noh Sangwoo Kim Su-Hyung park Hye Won Jeong Eui-cheol Shin Division of Infectious Disease Department of Internal MedicineSeoul National University HospitalSeoulRepublic of Korea Graduate School of Medical Science and Engineering Korea Advanced Institute of Science and Technology(KAIST)DaejeonRepublic of Korea Division of Infectious Diseases Department of Internal MedicineKorea University College of MedicineSeoulRepublic of Korea Department of Biomedical Systems Informatics Graduate School of Medical ScienceBrain Korea 21 ProjectYonsei University College of MedicineSeoulRepublic of Korea Department of Internal Medicine Chungbuk National University College of MedicineCheongjuRepublic of Korea The Center for Viral Immunology Korea Virus Research InstituteInstitute for Basic Science(IBS)DaejeonRepublic of Korea

In November 2021,the Omicron variant(B.1.1.529)emerged and was designated a variant of concern(VOC)by the World Health ***,Omicron was reported to extensively escape neutralizing antibodies elicited by COVID-19 vaccination or natural infection[1,2,3].However,whether Omicron evades the T cell immunity elicited by COVID-19 vaccination or natural infection remains to be *** address this issue,we analyzed the amino acid sequences of T cell epitopes identified from the original SARS-CoV-2 strain(Wuhan-Hu-1)in the Omicron variant(hCoV-19/South Africa/CERI-KRISP-K032284/2021).

关键词： neutral conserved elucidated

Design and Demonstration of Insect Mimicking Foldable Artificial Wing Using Four-Bar Linkage Systems

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Journal of Bionic Engineering 2014年第3期11卷 449-458页

作者： Quang-Tri Truong Byoma Wing Argyoganendro Hoon cheol park Laboratory of Applied Mechanics Faculty of Applied Science HCMUT Ho Chi Minh City 740-128 Vietnam Biomimetics and Intelligent Microsystem Laboratory Konkuk University Seoul 143-701 Korea Department of Advanced Technology Fusion Konkuk University Seoul 143-701 Korea Artificial Muscle Research Center Konkuk University Seoul 143-701 Korea

In this work, we develop an artificial foldable wing that mimics the hind wing of a beetle （Allomyrina dichotoma）. In real flight, the beetle unfolds forewings and hind wings, and maintains the unfolded configuration unless it is exhausted. The artificial wing has to be able to maintain a fully unfolded configuration while flapping at a desirable flapping frequency. The artificial foldable hind wing developed in this work is based on two four-bar linkages which adapt the behaviors of the beetle＇s hind wing. The four-bar-linkages are designed to mimic rotational motion of the wing base and the vein folding/unfolding motion of the beetle＇s hind wing. The behavior of the artificial wings, which are installed in a flapping-wing system, is observed using a high-speed camera. The observation shows that the wing could maintain a fully unfolded configuration during flapping motion. A series of thrust measurements are also conducted to estimate the force generated by the flapping-wing system with foldable artificial wings. Although the artificial foldable wings give added burden to the flapping-wing system because of its weight, the thrust measurement results show that the flapping-wing system could still generate reasonable thrust.

关键词： beetle's hind wing folding/unfolding motion flapping-wing system foldable wing four-bar linkage configuration thrust measurement

Atomic Dispersion of Rh on Interconnected Mo_(2)C Nanosheet Network Intimately Embedded in 3D Ni_(x)MoO_(y) Nanorod Arrays for pH-Universal Hydrogen Evolution

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