The State Estimator for Underwater Vehicle Systems

Kim, Hwan-Seong,You, Sam0Sang,Lee, Jin-Woo 한국해양대학교 산업기술연구소 2003 연구논문집 Vol.20 No.-

In this paper, an estimation method for extimating teh states of underwater vehicle systems with external unknown disturbance is proposed. First, the dynamics of underwater vehicle are induced by Taylor series expansion in the vertical plane and horizontal plane, respectively. For constructing the vehicle model, the external efforts, i.e., the sea surface disturbances, the current, wave and etc., are regarded as external unknown disturbances. Thus the disturbances is added as external input into state-space form of underwater vehicle systems. To estimate the state of systems with unknown disturbance, a disturbance observer which does not effected the external unknown input is proposed, and the existence condition for the observer is given. Finally, the effectiveness of the proposed disturbance observer for underwater vehicle systems is verified by using numerical simulation.

Korean English Teacher's Disempowerment in English-only Classes

Sung-Sam Hwang,Hyo-Sun Seo,Tae-Young Kim 한국사회언어학회 2010 사회언어학 Vol.18 No.1

Hwang, Sung-Sam, SeD, Hyo-Sun, Kim, Tae-Young. 2010. Korean English Teacher's Disempowerment in English-only Classes: A Case Study Focusing on Korea-specific Cultural Aspects. The Sociolinguistic journal of Korea 18(1). In this case study, we have focused on the disempowerment of a Korean English teacher (KET) in English-only classrooms. Six English as a foreign language (EFL) classrooms in a Korean high school were observed and analyzed by using interpretive discourse analysis. Out of the six classes, three representative classrooms were both video- and audio-taped. The results show that the English-only classes could weaken the KETs' power via three mechanisms: (a) calling the KETs' last name for choral greetings at the beginning of the class, (b) students' group solidarity and peer pressure between classmates, and (c) the students' excessively collaborative approach to peer assistance. It is argued that the exclusive English-only instruction disempowers the KETs' status and dismantles their vocational identity. In order to remedy the current situation, within a scaffolding supported by the eclectic use of first language where necessary for effective class management, KETs are empowered and overcome constraints imposed by the limited L2 oral competence of some non-native English teachers.

A Study of the Yang-gyeong-gyu-il-ui (兩景揆日儀) in the Joseon Dynasty

Yong Sam Lee,Sang Hyuk Kim,Byeong-Hee Mihn 한국우주과학회 2015 Journal of Astronomy and Space Sciences Vol.32 No.1

The Yang-gyeong-gyu-il-ui (兩景揆日儀) is a kind of elevation sundial using three wooden plates. Sang-hyeok Lee (李尙爀, 1810~?) and Byeong-cheol Nam (南秉哲, 1817~1863) gave descriptions of this sundial and explained how to use it in their Gyu-il-go (揆日考) and Ui-gi-jip-seol (儀器輯說), respectively. According to Gyu-il-go (揆日考) there are two horizontal plates and two vertical plates that have lines of season and time. Subseasonal (節候) lines are engraved between seasonal (節氣) lines, subdividing the interval into three equal lines of Cho-hu (初候, early subseason), Jung-hu (中候, mid subseason) and Mal-hu (末候, late subseason); there are 13 seasonal lines for a year, thus resulting in 37 subseasonal lines; also, there are 12 double-hour (時辰) lines for a day engraved on these plates. The only remaining artifact of Yang-gyeong-gyu-il-ui was made in 1849 (the 15th year of Heon-jong) and is kept at the Korea University Museum. We have compared and analyzed Yanggyeong- gyu-il-ui and similar western sundials. Also, we have reviewed the scientific aspect of this artifact and built a replica. Yang-gyeong-gyu-il-ui is a new model enhanced from the miniaturization development in the early Joseon Dynasty and can be applied to the southern part of the tropic line through a structure change.

A Study of the Yang-gyeong-gyu-il-ui (兩景揆日儀) in the Joseon Dynasty

Lee, Yong Sam,Kim, Sang Hyuk,Mihn, Byeong-Hee The Korean Space Science Society 2015 Journal of Astronomy and Space Sciences Vol.32 No.1

The Yang-gyeong-gyu-il-ui (兩景揆日儀) is a kind of elevation sundial using three wooden plates. Sang-hyeok Lee (李尙爀, 1810~?) and Byeong-cheol Nam (南秉哲, 1817~1863) gave descriptions of this sundial and explained how to use it in their Gyu-il-go (揆日考) and Ui-gi-jip-seol (儀器輯說), respectively. According to Gyu-il-go (揆日考) there are two horizontal plates and two vertical plates that have lines of season and time. Subseasonal (節候) lines are engraved between seasonal (節氣) lines, subdividing the interval into three equal lines of Cho-hu (初候, early subseason), Jung-hu (中候, mid subseason) and Mal-hu (末候, late subseason); there are 13 seasonal lines for a year, thus resulting in 37 subseasonal lines; also, there are 12 double-hour (時辰) lines for a day engraved on these plates. The only remaining artifact of Yang-gyeong-gyu-il-ui was made in 1849 (the $15^{th}$ year of Heon-jong) and is kept at the Korea University Museum. We have compared and analyzed Yang-gyeong-gyu-il-ui and similar western sundials. Also, we have reviewed the scientific aspect of this artifact and built a replica. Yang-gyeong-gyu-il-ui is a new model enhanced from the miniaturization development in the early Joseon Dynasty and can be applied to the southern part of the tropic line through a structure change.

Effect of Chungpaesagan-tang on ischemic damage induced by MCAO in spontaneously hypertensive rats

Kim, Ko-Eun,Kim, Soo-Yong,Kim, Eun-Young,Kim, Bum-Hoi,Shin, Jung-Won,Lee, Hyun-Sam,Sohn, Young-Joo,Jung, Hyuk-Sang,Sohn, Nak-Won Kyung Hee Oriental Medicine Research Center 2008 Oriental pharmacy and experimental medicine Vol.8 No.4

Chungpaesagan-tang (CPSGT) is most frequently used to treat ischemic brain injury in tradition Korean medicine. Clinically, cerebral ischemia is likely to be accompanied by preexisting or complicating disease. However, animal models used to examine the effects of herbal medicines on cerebral ischemia have not given this issue sufficient consideration. The present study was undertaken to determine the effects of CPSGT on focal cerebral ischemia in normal and SHR rats subjected to transient middle cerebral artery occlusion (MCAO). Animals were divided into four groups: Normal (Sprague-Dawley) rats subjected to MACO (the NC+MCAO group), normal rats subjected to MCAO and then administered CPSGT (NC + MCAO + CP), SHR rats subjected to MCAO (SHR + MCAO), and SHR rats subjected to MCAO and then administered CPSGT (SHR + MCAO + CP). MCAO was performed using the intraluminal method. CPSGT was administrated orally twice (1 and 4 h) after MCAO. All animals were sacrificed at 24 h postoperatively. Brain tissues were stained with hematoxylin & eosin, to examine the effect of CPSGT on ischemic brain tissues. In addition, changes in TNF-$\alpha$ expression in ischemic areas were examined by immunostaining. CPSGT was found to significantly reduce infarction areas in normal and SHR rats and infarction volumes in SHR rats. Similarly, CPGST markedly increased neuron numbers and sizes in all treated groups, except cell sizes in SHRs. Furthermore, CPSGT reduced TNF-$\alpha$ expression in MCAO administered SHR rats. The findings of the present study suggest that CPSGT effectively ameliorates neuron damage caused by MACO-induced cerebral ischemia, and that it has a significant neuroprotective effect after cerebral ischemia in SHR.

Evaluations of the Space Dose and Dose Reductions in Patients and Practitioners by Using the C-arm X-ray Tube Shielding Devices Developed in Our Laboratory

Kim, Jae Seok,Kim, Sung Ho,Lee, Bu Hyung,Kwon, Soo Il,Jung, Hai Jo,Hoe, Seong Wook,Son, Jin Hyun,Kang, Byeong Sam Korean Society of Medical Physics 2016 의학물리 Vol.27 No.4

The present study used a digital angiography x-ray device to measure the space dose and exposure dose of patients and practitioners using x-ray tube shielding devices developed in our laboratory. The intent of the study was to reduce the space dose within the test room, and to reduce the exposure dose of patients and practitioners. The patient and practitioner exposure doses were measured in five configurations in a human body model. The glass dosimeter was placed on the eye lenses, thyroid glands, left shoulder, right shoulder, and gonads. The beam was collimated at full size and at a 48% reduction for a comparative analysis of the measurements. The space dose was measured with an ion chamber at distances of 50 cm, 100 cm, and 150 cm from the x-ray tube under the following conditions: no shielding device; a shielding device made of 3-mm-thick lead (Pb) [Pb 3 mm shield], and a shielding device made of 3-mm-thick Pb (outside) and 3-mm-thick aluminum (Al) (inside) [Pb 3 mm＋Al 3 mm shield]. The absorbed dose was the lowest when the 3-mm-thick Pb＋3-mm-thick Al shield was used. For measurements made with collimated beams with a 48% reduction, the dose was the lowest at $154{\mu}Gy$ when the 3-mm-thick Pb＋3-mm-thick Al shield was used, and was $9{\mu}Gy$ lower than the measurements made with no shielding device. If the space dose can be reduced by 20% in all situations where the C-arm is employed by using the x-ray tube shielding devices developed in our laboratory, this is expected to play an important role in reducing the annual exposure dose for patients, practitioners, and assistants.

Comparison of Antioxidant and Antimicrobial Activities of Supercritical Fluid Extracts and Marc Extracts from Cinnamomum verum

Sung Jin Park(박성진),Mi Hee Yu(유미희),Ji Eun Kim(김지은),Sam Pin Lee(이삼빈),In Seon Lee(이인선) 한국생명과학회 2012 생명과학회지 Vol.22 No.3

본 연구에서는 계피 초임계 추출물(SFE oil)과 박 추출물(SFM), 80% methanol 추출물, cinnamaldehye의 항균, 항산화력을 비교하였다. 그 결과 추출조건에 따라 뚜렷한 효과의 차이를 나타내었으며, 80% methanol 추출물과 SFM이 강력한 항산화능 보였다. 반면에 항균효과에서는 cinnamaldehyde와 SFE oil에서 식중독균에 대한 항균효과가 뛰어났으며, 초임계를 이용한 추출에서 cinnamaldehyde 이외에 다른 camphene, cineole, eugenol 등의 정유성분들이 항균효과에 영향을 미친 것으로 생각된다. 이러한 결과로부터, 초임계 추출법이 항균물질 및 정유성분 추출에 매우 용이할 뿐만 아니라, 초임계 추출 후 폐기되고 있는 박에서도 유용성분이 함유되어 있음을 확인하였으므로 계피의 초임계 추출물 및 박 추출물 모두 기능성 천연소재로의 활용이 가능할 것으로 기대된다. This study was performed to evaluate the antioxidant and antimicrobiological effects of supercritical fluid extracts (SFEs) and Marc methanol extracts (SFMs) from Cinnamomum verum. Reducing effects on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and ABTS radical scavenging were investigated. SFM exhibited higher antioxidant activities in DPPH and ABTS radical scavenging assay. Measurements of the antimicrobial activity were used for Gram-positive bacteria (four strains) and Gram-negative bacteria (four strains). The antimicrobial activities of the SFE and SFM against gram-positive and gram-negative bacteria revealed that SFE had a higher inhibition zone than SFM. Cinnamaldehyde, the active compound of C. verum, had a higher content in SFM (35% at 300 bar, 30℃) than methanol extracts from C. verum (0.5%). These results indicate that not only SFE oil, but also SFM, could be a good source for the food industry.

The Mitochondrial Genome of the Oriental Mole Cricket, Gryllotalpa orientalis: Complete DNA Sequence, Genome Organization, and Phylogenetic Analysis with Other Insects

Kim Ik-Soo,Cha So-Young,Yoon Myung-Hee,Hwang Jae-Sam,Lee Sang-Mong,Jin Byune-Rae 한국응용곤충학회 2004 한국응용곤충학회 학술대회논문집 Vol.2004 No.1

M¨ossbauer Studies on Cation Distributions and Superexchange Interactions in Cu0.2Fe2.8O4

Sam Jin Kim,Hyunkyung Choi,Jung Tae Lim,Chul Sung Kim,Eun Joo Hahn 한국물리학회 2016 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.68 No.3

The cation distributions and the superexchange interactions of Cu0.2Fe2.8O4 have been studied by M¨ossbauer spectroscopy and X-ray diffraction. The crystal is found to have a cubic spinel structure with the lattice constant a0 = 8.4007 ± 0.0004 °A. The M¨ossbauer spectra show line broadening in the octahedral (B) site, which is interpreted by probability distribution of cations. The dominant superexchange interaction is found to be an antiferromagnetic intersublattice A-OB superexchange interaction, and its strength is JA−B = −20.7 kB. The intrasublattice A-O-A superexchange interaction is also antiferromagnetic and its strength is JA−A = −9.3 kB. The weakest superexchange interaction is the ferromagnetic B-O-B interaction: JB−B = 0.7 kB. The Debye temperatures of the tetrahedral and the octahedral sites are found to be A = 459 ± 5 K and B = 351 ± 5 K, respectively.

Molecular cloning and analysis of the <i>Thermus caldophilus</i> ADP-glucose pyrophosphorylase

Kim, Yong-Sam,Sohn, Hosung,Jin, Un-Ho,Suh, Seok-Jong,Lee, Sang Chul,Jeon, Jae Heung,Lee, Dae-Sil,Kim, Cheorl-Ho,Ko, Jeong Heon IPC Science and Technology Press 2007 Enzyme and microbial technology Vol.41 No.4

<P><B>Abstract</B></P><P>Previously, we have purified a highly thermostable ADP-glucose pyrophosphorylase (EC 2.7.7.27; AGPase) from <I>Thermus caldophilus</I> GK-24. In the present paper, we further report the molecular cloning and characterization of the thermostable bacterial AGPase. Using a 0.6-kb DNA probe obtained by polymerase chain reaction (PCR) with a primer set deduced from the <I>N</I>-terminal and internal amino acid sequence, the AGPase gene was cloned. The cloned AGPase gene had a 1245-bp open reading frame that encodes a protein of 414 amino acids. Then, the full-length AGPase gene was further cloned into the pHCE19T(II) vector and was expressed in <I>Escherichia coli</I> DH5α. Western analysis of the recombinant enzyme showed the same immunity as the wild-type enzyme with a molecular mass of ca. 46kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The kinetic parameters of the recombinant AGPase were basically similar to the wild type. The <I>N</I>-terminal region of <I>T. caldophilus</I> AGPase showed a partial similarity to that of <I>E. coli,</I> and R336 and P295 were identical to those of <I>E. coli</I> AGPase. In addition, sequence comparison revealed that R177 and P235 of <I>T. caldophilus</I> AGPase were aligned with K195 and K247 of <I>E. coli,</I> and K376 with R386, while K195 residue of <I>E. coli</I> was reported to be located in the glucose-1-phosphate (Glc-1-P) substrate binding region.</P>