http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
An aerodynamic model for insect flapping wings in forward flight
Han, Jong-Seob,Chang, Jo Won,Han, Jae-Hung IOP Publishing 2017 Bioinspiration & biomimetics Vol.12 No.3
<P>This paper proposes a semi-empirical quasi-steady aerodynamic model of a flapping wing in forward flight. A total of 147 individual cases, which consisted of advance ratios J of 0 ( hovering), 0.125, 0.25, 0.5, 0.75, 1 and infinity, and angles of attack alpha of -5 to 95 degrees at intervals of 5 degrees, were examined to extract the aerodynamic coefficients. The Polhamus leading-edge suction analogy and power functions were then employed to establish the aerodynamic model. In order to preserve the existing level of simplicity, K-P and K-V, the correction factors of the potential and vortex force models, were rebuilt as functions of J and alpha. The estimations were nearly identical to direct force/moment measurements which were obtained from both artificial and practical wingbeat motions of a hawkmoth. The model effectively compensated for the influences of J, particularly showing outstanding moment estimation capabilities. With this model, we found that using a lower value of a during the downstroke would be an effective strategy for generating adequate lift in forward flight. The rotational force and moment components had noticeable portions generating both thrust and counteract pitching moment during pronation. In the upstroke phase, the added mass component played a major role in generating thrust in forward flight. The proposed model would be useful for a better understanding of flight stability, control, and the dynamic characteristics of flapping wing flyers, and for designing flapping-wing micro air vehicles.</P>
Hung Sun Koh,Kyung Hee Jang,Jang Geun Oh,Eui Dong Han,Jae Eun Jo,Eui Jeong Ham,Seon Ki Jeong,Jong Hyek Lee,Kwang Seon Kim,Gu Hee Kweon,Seong Teak In 한국동물분류학회 2012 Animal Systematics, Evolution and Diversity Vol.28 No.2
The objective of this study was to determine the degree of mitochondrial DNA (mtDNA) divergence between two subspecies of Mustela sibirica from Korea (M. s. coreanus on the Korean Peninsula and M. s. quelpartis on Jeju Island) and to examine the taxonomic status of M. s. quelpartis. Thus, we obtained complete sequences of mtDNA cytochrome b gene (1,140 bp) from the two subspecies, and these sequences were compared to a corresponding haplotype of M. s. coreanus, downloaded from GenBank. From this analysis, it was observed that the sequences from monogenic M. s. quelpartis on Jeju Island were identical to the sequences of four M. s. coreanus from four locations across the Korean Peninsula, and that the two subspecies formed a single clade; the average nucleotide distance between the two subspecies was 0.26% (range, 0.00 to 0.53%). We found that the subspecies quelpartis is not genetically distinct from the subspecies coreanus, and that this cytochrome b sequencing result does not support the current classification, distinguishing these two subspecies by pelage color. Further systematic analyses using morphometric characters and other DNA markers are necessary to confirm the taxonomic status of M. s. quelpartis.
Bacterial Black Stem Rot on Angelica acutiloba Caused by Xanthomonas campestris
Han, Kwang-Seop,Shim, Myoung-Youg,Oh, In-Seok,Han, Kyu-Hung,Park, Jae-Eul The Korean Society of Plant Pathology 2002 Plant Pathology Journal Vol.18 No.1
Soaked black rot symptom was observed on the stem of Angelica acutiloba from July to August 2000 at Kumsan, Chungnam in Korea. This disease usually occurred under humid and high temperature conditions. The lesions on the stem appeared as soft rot with brown elliptical spots, which developed into large black spots at a later stage. When the bacterial isolates from the diseased plants were inoculated onto healthy plants by artificial needle prick method, symptoms similar to that observed in the fields developed. According to the cultural characteristics and pathogenicity of the isolates on the host plant the causal bacterium was identified as Xanthomonas campestris. This study proposed that the disease be named "bacterial black stem rot of A. acutiloba"loba".
Hung Sun Koh, Kyung Hee Jang, Eui Dong Han, Jae Eun Jo, Seon Ki Jeong, Eui Jeong Ham, Seong Taek In, Jong Hyek Lee, Gu Hee Kweon, Kwang Seon Kim 충북대학교 동물의학연구소 2012 Journal of Biomedical and Translational Research Vol.13 No.2
To identify subspecies and stocks of minke whale meats purchased from Korean markets during 2005-2007, we first obtained their complete sequences of mitochondrial DNA cytochrome b and control region sequences, and compared these sequences to the corresponding sequences of the common minke whale (Balaenoptera acutorostrata), obtained from GenBank. From analyses with partial cytochrome b sequences (383 bp) and non-coding, partial control region sequences (463 bp), Korean mink whale meats are identified as products from the North Pacific minke whale (B. a. scammoni). In addition, the sequences of the partial control region from these meats showed G at site no. 298 and G or A at site no. 463, and the meats appeared to originate from the J stock within this subspecies. Thus, because the J stock has been protected since 1986, implementation of strict regulation measures to reduce their accidental fisheries by catch seems urgent. In addition, B. a. scammoni is distinct from B. a. acutorostrata, with an average Jukes-Cantor distance of 2.21% in the complete control region sequence analysis (935 bp) and 1.31% in the complete cytochrome b gene sequence analysis; the current results support the current subspecies classification, although further sequencing analyses with nuclear genes are necessary.
Jae Ha Lee,Hang Jea Jang,Jin Han Park,Yong Kyun Kim,Ho Ki Min,Sun Young Kim,Hyun-kuk Kim 대한중환자의학회 2016 Acute and Critical Care Vol.31 No.3
Amniotic fluid embolism is rare but is one of the most catastrophic complications in the peripartum period. This syndrome is caused by a maternal anaphylactic reaction to the introduction of fetal material into the pulmonary circulation. When amniotic fluid embolism is suspected, the immediate application of extracorporeal mechanical circulatory support such as veno-arterial extracorporeal membrane oxygenation (ECMO) or cardiopulmonary bypass should be considered. Without the application of extracorporeal mechanical circulatory support, medical supportive care might not be sufficient to maintain cardiopulmonary stabilization in severe cases of amniotic fluid embolism. In this report, we present the case of a 36-year-old pregnant woman who developed an amniotic fluid embolism immediately after a cesarean section. Her catastrophic event started with the sudden onset of severe hypoxia, followed by circulatory collapse within 8 minutes. The veno-arterial mode of extracorporeal membrane oxygenation was initiated immediately. She was successfully resuscitated but with impaired cognitive function. Thus, urgent ECMO should be considered when amniotic fluid embolism syndrome is suspected in patients presenting acute cardiopulmonary collapse.
Ornithopter Modeling for Flight Simulation
Jae-Hung Han,Jin-Young Lee,Dae-Kwan Kim 제어로봇시스템학회 2008 제어로봇시스템학회 국제학술대회 논문집 Vol.2008 No.10
This paper presents the flight simulation of flapping-wing air vehicles (ornithopters) based on a refined flapping-wing aerodynamic model; the modified strip theory (MST). Compared with conventional types of micro air vehicles (MAVs), flapping MAVs show more complicated flight behaviors due to their complex wing motions and aerodynamics. In this paper, a flight dynamic model of an ornithopter is presented to analyze its stability and controllability. This paper focuses on the stabilization and path-following control of the ornithopter by adjusting the flapping frequency and tail-wing’s elevation angle. In spite of its nonlinear and complex behavior, controlling the tail-wing pitch angle can be effective for the stabilization in longitudinal motion of the ornithopter.