• Journal of computational fluids engineering
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• v.21 no.2
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• pp.112-119
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• 2016

NEXTSat-1 is the next-generation small-size artificial satellite system planed by the Satellite Technology Research Center(SatTReC) in Korea Advanced Institute of Science and Technology(KAIST). For the control of attitude and transition of the orbit, the system has adopted a RHM(Resisto-jet Head Module), which has a very simple geometry with a reasonable efficiency. An axisymmetric model is devised with two coil-resistance heaters using xenon(Xe) gas, and the minimum required specific impulse is 60 seconds under the thrust more than 30 milli-Newton. To design the module, seven basic parameters should be decided: the nozzle shape, the power distribution of heater, the pressure drop of filter, the diameter of nozzle throat, the slant length and the angle of nozzle, and the size of reservoir, etc. After quasi one-dimensional analysis, a theoretical value of specific impulse is calculated, and the optima of parameters are found out from the baseline with a series of multi-physical numerical simulations based on the compressible Navier-Stokes equations for gas and the heat conduction energy equation for solid. A commercial code, COMSOL Multiphysics is used for the computation with a FEM (finite element method) based numerical scheme. The final values of design parameters indicate 5.8% better performance than those of baseline design after the verification with all the tuned parameters. The present method should be effective to reduce the time cost of trial and error in the development of RHM, the thruster of NEXTSat-1.

• Korean Institute of Interior Design Journal
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• no.1
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• pp.39-45
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• 1992

Today the design is recognized as indispensible part in business activities and it is demanded as one of the management strategies. since the ultimate goal of a hotel lines in the pursuit of profit, it is important that the design of a hotel faithfuly reflects the demands of management at the time of its construction planning. Furthermore, hotel planning undergoes a complicated design phases on a large scale, thus, utilization of a design process that accomodates retional approaches scientific and structural design activities, which will further reduce errors in design steps and pave a way for effective attainment of the target. Especially the management and designers review and confirm the design in relation to the strategic manegiable objective sat the early basic stage. The baseline set here will serve as a direction for the detailed design. In this context, this thesis formulates a reference baseline in dividing the space in view of the overall profitability and is based upon a survey conducted on the correlation between the operation of food and beverage section and the space. First, downtown hotels now take on the role of a public facility to a great extent and the number of Koreans who visit the autxiliary facilities of hotel increases. Second, recently revenue from a food and beverage section is in downtown and the trend is especially obrious at western restaurant, buffet and bar. This necessitates the reevaluation of the business space allocation. Third, sales promotion plan includes diversification, dessection and scaling down of the food and beverage section areas, Fourth, a proper number of seats must be determined in regard to the average area of one seat shown in the survey. Fifth, dense seat arrangement would entail a curtailment rather than a hike in revenue. Sixth, the installation of private dining room is on the rise and in particular, in Japanese and Chinese restaurants. Seventh, business space with declined revenue tends to induce the integration of similar businesses.

• Journal of The Korean Society of Agricultural Engineers
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• v.60 no.3
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• pp.135-148
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• 2018

Reservoir sedimentation is a major environmental issue, and various sediment load controls and plans have been proposed to secure clean and safe water resources. The objectives of this study were to estimate soil loss in the upper basins and predict sediment deposition in Ipjang reservoir using hydrologic and hydraulic model. To do so, SWAT (Soil and Water Assessment Tool) and EFDC (Environmental Fluid Dynamics Code) was used to estimate soil loss in two upper basins and to predict spatial distribution and amount of sediment deposition in the Ipjang reservoir, respectively. The hydrologic modeling results showed that annual average soil loss from the upper basins was 500 ton. The hydraulic modeling results demonstrated that sediment particles transported to the reservoir were mostly trapped in the vicinity of the reservoir inlet and then moved toward the bank over time. If long-term water quality monitoring and sediment survey are performed, this study can be used as a tool for predicting the dredging amount, dredging location and proper dredging cycle in the reservoir. The study findings are expected to be used as a basis to establish management solutions for sediment reduction.

• Korean Journal of Veterinary Service
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• v.32 no.4
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• pp.315-323
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• 2009

Foot-and-mouth disease (FMD) virus exists in seven serotypes and is known to be a highly contagious disease that is hard to eradicate from the world. The O, A, Asia1 and SAT2 serotypes commonly infected cattle, sheep and goats during 2007~2009 throughout the world. In particular, the outbreak of the Asia1 serotype in China appeared in all areas from 2005 and is still present. Surprisingly, in 2009, Taiwan reported the first outbreak of the type O serotype since 2001. Then type A appeared in China for the first time since the early 1960s. The virus shows a close relationship to the viruses from Southeast Asia suggesting one or more recent introductions into China in the OIE reports. Recently the subtype of A/Iran05 spread to nearby countries exhibiting genomic evolution. The use of molecular epidemiology is an important tool in understanding and consequently controlling the FMD virus. The phylogenetic analysis with VP1 gene was especially useful for molecular epidemiological studies and showed the same pattern which matches with serotype classification. This paper describes basic information about the disease, and the serotype-specific characteristics and evolution to perform molecular epidemiological analysis. Furthermore, we show the importance of the genetic evolution on the FMD serotypes in global surveillance and molecular epidemiology of FMD for outbreak investigation.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.40 no.4
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• pp.275-285
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• 2003

The now video coding standard H.264 employs variable block size motion compensation, multiple references, and quarter-pel motion vector accuracy. These techniques are key features to accomplish higher coding gain, however, at the same time main factors that increase overall computational complexity. Therefore, in order to apply H.264 to many applications, key techniques are requested to improve their speed. For this reason, we propose a fast motion estimation which is suited for variable block size motion communication. In addition, we propose a fast mode decision method to choose the best mode at early stage. Experimental results show the reduction of the number of SAT SATD calculations by a factor of 4.5 and 2.6 times respectively, when we compare the proposed fast motion estimation and the conventional MVFAS $T^{［8-10］}$. Besides, the number of RDcost computations is reduced by about 45%. Therefore, the proposed methods reduces significantly its computational complexity without noticeable coding loss.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.17 no.4
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• pp.379-388
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• 1995

This study was based on a series of 369 patients with Oral and Maxillofacial injuries treated at Kumi Hospital, College of Medicine, Soon-Chun-Hyang University from Jan. 1992 to Dec. 1994. The results obtained were as follows : 1. The number of male patient was 310 and that of female was 59, leading to 5.3 : 1 of male-female ratio, and the 3rd decade was the highest age group in incidence. 2. Weekly incidence was the highest in Sun. & Sat. and monthly incidence was the highest in Nov.& Oct. 3. Causes as follows : traffic accident 41.9%, slip& fall down 25.4%, human trouble 16.5%, industrial accident 7.5%, sports 6.7%, etc. 4. Site distribution as follows : mandible fracture 32.3%, maxilla fracture 4.8%, zygoma fracture 21.4%, nasal bone fracture 34.1%, orbital& ethmoidal fracture 4.6%. 5. The most common site of mandible was symphysis & angle, and the ratio of OR & CR was 1.3 : 1. 6. The most common site of maxilla was Le Fort 1, 2, and the ratio of OR & CR was 3 : 1. 7. The most common site of zygoma was body, the ratio of OR & CR was 3.3 : 1. 8 . The mean period of intermaxillary fixation was 4.33weeks. 9. Combined injury in facial fracture was 35.8% : The facial fracture were most frequently combind with head & neck(47.0%), upper extremities and abdomen(9.8%). 10. The mean elapsed time from injury to hospital was 1.9days, and that to operation was 5.1days. 11. The mean number of combined teeth injury was 0.6, and percent of combined soft tissue injury of face was 51.3%. 12. Post-operative complication occurred in 4 out of 323 cases. all of that was infection.

• Journal of architectural history
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• v.12 no.1 s.33
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• pp.43-58
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• 2003

This study is to analyze spatial structure of Eupchi(邑治) on Chungchong province with Chungchong-do regional maps(忠淸道地方地圖) and Eupjis(邑誌, topography) being compiled in the late Chosun dynasty. According to the analysis of it in this study, we make conclusions as follows; 1. Gunhyeon(郡縣) which had been Eupseong(邑城) on Chungchong-do in Chosun dynasty was 13 provinces, and the construction of Eupseong was the coast Eupseong built for the purpose of defense and military Eupseong built at Byeongyeong(兵營) and Geojin(巨鎭). And a measure used In the construction of a castle was Pobaekcheok(布帛尺) used to survey a frontier defence in Chosun dynasty, also Jucheok(周尺) or Yeongjocheok(營造尺) could be assumed to be wide use at that time. 2. Eupchi of Chungchong-do Gunhyeon was almost disposed to the south direction, also had been Jinsan(鎭山) safeguarding it. With relation to Jwahyang(坐向) and Jinsan, its Jinsan and Myeongdang-cheon(明堂川) match each other in location of Eupchi, as it get Jinsan sat, and take main river in front of it. And provincial government office to be the center of a Eupchi is organized into Gaeksa(客舍), Dongheon(東軒), Naea(內衙), Hyangcheong(鄕廳), and practical business facilities, Jakcheong(作廳) or Jangcheong etc., the others is composed for the use of support of those. 3. In most Eupchi in Chungchong province, the layout Sajikdan(社稷壇) and Yeodan(礪壇) was gone with a principle as they were disposed in the west and the north with Eupchi. Seonghwangdan(城隍壇) and Munmyo(文廟) was built in defiance of a principle, as a condition of province. Jangsi(場市) of Eupchi was opened in front of government office or Gaeksa, and the Gunhyeon which had Eupseong was established in the inside and outside of Eupseong.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.224-224
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• 2017

In plants, cysteine(Cys) is decisive for protein and glutathione that acts as an indispensable sulfur grantor for methionine and many other sulfur containing secondary products. Cys formation is involved in the consecutive two reactions using two enzymes-serine acetyl transferase (SAT) and O-acetylserine (thiol)lyase (OASTL) and appeared in plant cytosol, chloroplast and mitochondria. OASTL is able to produce mimosine with 3-hydroxy-4-pyridone (3H4P) in lieu of $H_2S$ for Cys. In this report, we describe the first time cloning, purification and characterization of cytosolic(cy)OASTL from M. pudica and its expression in Escherichia coli and try to find out the cross link between this OASTL and the mimosine formation and to elucidate the metabolic role of cy-OASTL in M. pudica. The purified recombinant protein was 34.7 KDa. The optimum reaction pH and temperature was 6.5 and $50^{\circ}C$, respectively. The Michaelis constant (Km) and the Vmax value of the enzyme was $252{\pm}25{\mu}M$ and $57{\pm}3{\mu}M\;cysteine\;min^{-1}\;{\mu}g\;protein^{-1}$ for sulfide and $159{\pm}21{\mu}M$ and $58{\pm}2.4{\mu}M\;cysteine\;min^{-1}\;{\mu}g\;protein^{-1}$ for OAS subsequently. After cleaving the His-tag, we tried to observe cy-OASTL to form mimosine with appropriate substrate but it was not successful. It may be concluded that cy-OASTL of the present study is only Cys specific, not mimosine.

• Journal of IKEEE
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• v.14 no.1
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• pp.55-64
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• 2010

In this paper, we proposed the novel TIGBT with an additional p-type MOS structure to achieve the improved trade-off between turn-off and on-state voltage drop(Vce(sat)). These low on-resistance and the fast switching characteristics of the proposed TIGBT are caused by an enhanced electron current injection efficiency which is caused by additional p-type MOS structure. In the simulation result, the proposed TIGBT has the lower on state voltage of 1.67V and the shorter turn-off time of 3.1us than those of the conventional TIGBT(2.25V, 3.4us).

• Journal of the Korean Society for Aviation and Aeronautics
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• v.17 no.3
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• pp.1-6
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• 2009

Since the success of the first flight, vast advancements have been made to the aircrafts with recent developments incorporating highly complex mechanisms, placing greater emphasis on the competence of the pilot. Studies are currently being undertaken to effectively source the trainee pilots with the most ideal level of aptitude for aviation with an aim to optimise the selection process with focus on economy and time, while research into identifying the optimal human characteristics for aviation is being done. As part of the selection process, number of tests is arranged with focus on the individual competence, suitability for flight, health status, aptitude and intelligence with the results of the tests used as reference materials during the selection procedure. This study has investigated the effect the academic competence has on the aptitude for aviation amongst many other abilities of human beings and the findings show that higher levels of aptitude have been demonstrated by the students who have displayed academic excellence across all the courses with statistics pointing to a positive correlation between the two subjects. This supports the theory that students who are academically superior have higher probability of being found to possess greater level of flight aptitude. The outcome of the study iterates the fact that academic competence of the students should not be regarded lightly in the selection process. Based on the current study, it is believed that a research into determining the relationship between the SAT results, average yearly grade and flight aptitude will help identify the key factors in possessing high level of flight aptitude with greater certainty.