모형항공기 엔진 개발

임경호,전창수,김영진 한국 항공대학교 항공산업기술연구소 1999 航空宇宙産業技術硏究所 硏究誌 Vol.9 No.-

모형항공기 엔진을 개발을 위해 우선 엔진 크기의 기초설계변수 선정은 기존 제품들에 대한 자료를 분석하여 구하였다. 엔진블럭의 외형이 블록 온도분포에 미치는 영향을 살펴본 결과, 블록의 단면적이 동일하다는 조건하에서, 원형보다는 직사각형에 가가운 형상이 조금 좋은 것으로 나타났다. 엔진 블록 휜의 기하학적 변수로 흰 가격/깊이는 0.3, 흰 두께/깊이는 1.5 정도로 설계되는 것이 블록의 온도 분포 측면에서 바람직한 것으로 판단된다. 간단한 pony-브레이크 동력계로 회전수와 로드셀에 가해지는 힘을 측정하여 엔진 축동력을 근사하게 평가할 수 있음을 확인하였고, 고회전수에서의 측정을 위해서는 보다 정밀한 측정장비가 요구될 것으로 판단된다. A preliminary design study on development of model aircraft engine were initiated. For new model engine, the database was collected which were based on various existing engine models as a function of performance parameters and engine geometries. From these data, basic engine design geometric parameters were determined. For fixing the shape of engine block, circular block and rectangular block with rounded corners were compared in view of temperature distributions in engine block under same flow/thermal conditions. As a result, the difference seems to be very minor, but a little bit better temperature distribution was developed in case of rectangular one. To improve cooling effect due to cooling fins on engine block, the effects of fin geometries on cooling were investigated using commercial CFD software. Better cooling would be anticipated with fins which has fin clearance to depth ratio of 0.3 and fin thickness to depth ratio of 1.5. Simple pony-brake dynamometer system developed for the prediction of small engine performance, measuring the force and rpm with load-cell and stroboscope.

자동차 공조용 핀형 열교환기의 성능특성에 관한 연구

홍경한,전상신,이승재,박찬수,권일욱,김재열,김병철,하옥남 한국공작기계학회 2004 한국생산제조학회지 Vol.13 No.4

Fin-tube type(Fin-type) heat exchanger has been tested in order to replace the heat exchanger of parallel flow type(P.F-type) which is now widly used in automobile air conditioning system. The following conclusions are drawn by the comparison of the characteristics of the heat exchangers. Evaporator and condenser capacities and COP(Coefficience of performance) were varied as with the compressor speed, outdoor air temperature and air flow rate changed, which much influenced on the characteristics of the air conditioning system. Evaporator and condenser capacities were increased with increasing compressor speed and outdoor air temperature. Evaporator and condenser pressures of Fin- type were decreased by 7% and 5% respectively compared with those of P.F-type. The COP of Fin-type was decreased with increasing outdoor air temperature and compressor speed. The COP of P.F-type was decreased by 14% compared with that of Fin-type.

도플러검사법을 이용한 새로운 심기능평가법 : 급성 심근경색증에 의한 심기능장애의 선별진단법으로서 심기능지표의 유용성 The Utility of Cardiac Performance Index in the Screening Test of Cardiac Dysfunction due to Acute Myocardial Infarction

김원,임경수,이영주,최옥경,전정민 대한응급의학회 1999 대한응급의학회지 Vol.10 No.4

Background : Because systolic and diastolic dysfunction frequently coexist in acute myocardial infarction (AMI), we hypothesize that a combined measure of ventricular performance using Doppler echocardiography may be more sensitive and time-saving diagnostic tool for the evaluation of patients presenting with cardiogenic chest pain. Method and Results : Seventy-one patients with AMI (47 male, 59±11 years) and 45 patients with normal coronary artery (29 male, 52±11 years) were included in the study for measurement of cardiac performance index and established parameters of ventricular function using conventional echo-Doppler methods. a new derived index of cardiac performance: (ICT+IRT)/ET, was obtained by subtracting ejection time(ET) from the interval between cessation and onset of the mitral inflow velocity to give the sum of isovolumic contraction time(ICT) and isovolumic relaxation time(IRT). The mean value of the index was significantly different between normal and AMI(p<0.01). The degree of inter-group overlap was smaller for the index compared to other parameters. within functional groups, the value of the index did not appear to be related to heart rate, mean arterial pressure and the degree of mitral regurgitation. Conclusion : cardiac performance index is a conceptually new, simple and reproducible Doppler index of combined systolic and diastolic myocardial performance, and it is useful as screening test for patients with cardiac dysfunction due to AMI

서울 시내 일부 대학생의 성지식과 성태도에 관한 연구

김보배,노은경,박서영,박영,오승희,전영란,차현진,윤희상,김수지,이자형 이화여자대학교 간호과학대학 2004 이화간호학회지 Vol.- No.38

This study surveyed and analyzed comparatively college students-knowledge' attitude, was to cultivate the right knowledge and attitude on sex, and serve the foundational data for the suitable sex education. The purpose of the study was to identify and examine: 1) students; sexual knowledge and sexual attitude; 2) the differences between variables of gender, age, and self-perceived sexual knowledge in relation to sexual knowledge and sexual attitude; and 3) the relationship between sexual knowledge and sexual attitude. For this study the questionaires were given to 300 students from five different universities located seoul areas. the questionaires were collected Jenuary 8th to 15th in 2004. Two hundred and nigty one samples were analyzed for the study. The adapted SKAT(saxual knowledge & attitude test; Lief & Reed, 1986) was used to determine sexual knowledge and the students' sexual attitude. Collected data were analyzed statistically by means of percentage, t-test, ANOVA test, and pearson correlation analysis with SPSS 12.0 package program. The main results of this analysis are as follows: Participants consisted of male(48.1%) and female(51.9%) which were mainly between the ages of 21.25(71.8%) with an age range of 19 to 30. Knowledge of sexual disease was scored highest of 92.4%, and konwledge of the knowledge of the male and female's anatomy was the lowest at 60.9%. The respondents' level of sexual attitude was tolerant as on average 3.66(on the basis of 5) Relating to the items, the respondents' score of the sexual curiosity was 4.16, sexual behavior 3.85, self-consolation 3.81, aborthon 3.23, virgine 3.19, extramarital experiences 3.17. There were no significant differences in sexual knowledge between male and females, between younger and older students, residence, sexual experience, and how students mainly obtained their sexual knowledge. But a significant difference was also found religion in their sexual attitude(p<.005). In addition, results showed the relationship between sexual knowledge and sexual attitude(P=0.332).

Development of marker-free transgenic rice expressing wheat storage protein, TaGlu-Ax1, for increasing quality processing of bread and noodle

Soo-Kwon Park,So-Hyeon Baek,Dool-Yi Kim,Myoung-Ryoul Park,Na-Ra Lee,Kyoung Soon Shin,Su-Kyoung Jeon,Eun-Jae Kim,Sun-Lim Kim,Jung-Kyoung Moon 한국육종학회 2015 한국육종학회 심포지엄 Vol.2015 No.07

Rice flour is used in many food products. However, dough made from rice lacks extensibility and elasticity, whereas that of wheat is suitable for many food products including breads. We have produced marker-free transgenic rice plants containing a wheat TaGlu-Ax1 gene encoding the HMG-GS from the Korean wheat cultivar ‘Jokyeong’ using the Agrobacteriummediated co-transformation method. The TaGlu-Bx7-own promoter was inserted into a binary vector for seed-specific expression of the TaGlu-Ax1 gene. Two expression cassettes comprised of separate DNA fragments containing only TaGlu-Ax1 and hygromycin phosphotransferase II (HPTII) resistance genes were introduced separately to the Agrobacterium tumefaciens EHA105 strain for co-infection. Each EHA105 strain harboring TaGlu-Ax1 or HPTII was infected to rice calli at a 3:1 ratio of TaGlu-Ax1 and HPTII, respectively. Then, among 210 hygromycin-resistant T0 plants, we obtained 20 transgenic lines with both TaGlu-Ax1 and HPTII genes inserted into the rice genome. We reconfirmed integration of the TaGlu-Ax1 gene into the rice genome by Southern blot analysis. Transcripts and proteins of the wheat TaGlu-Ax1 were stably expressed in the rice T1 seeds. Finally, the marker-free plants harboring only the TaGlu-Ax1 gene were successfully screened at the T1 generation.

In-situ rf plasma treatment of multiwall carbon nanotubes with Various Reactive Gases for Enhanced Field Emission

Kyoung Soo Ahn,Ji Hoon Kim,Kyoung Nam Lee,Chang Hyo Lee,Chae Ok Kim,Jin Pyo Hong,정현식,Yu Jin Jeon 한국물리학회 2004 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.45 No.1

Well-aligned multi-wall carbon nanotubes (MWNTs) were fabricated at a low temperature of 400 C by utilizing a radio-frequency plasma-enhanced chemical vapor deposition (rf-PECVD) system. The MWNTs were in-situ treated with external rf plasma sources, such as hydrogen (H2) and ammonia (NH3), in order to enhance the structural and electrical properties of the MWNTs. Structural properties of carbon nanotubes were investigated by using scanning electron microscopy, Fourier transform infrared spectroscopy, energy-dispersive spectrometry and transmission electron microscopy. Finally, the emission properties of the MWNTs treated with various gases were also measured, for application in eld emission displays in the near future.

Molecular analysis of a novel antioxidant 2-Cys Prx isolated from mungbean

Young Soo Chung,Eun Hee Jeon,Jai Heon Lee,Eun Sook Chung,Chang Woo Cho,Kyoung Mee Kim,Kyoung Soo Kim,Hyun A So,Yeon Joo Kwack 한국육종학회 2009 한국육종학회 학술발표회 발표요지 Vol.41 No.1

Dynamic Partitioning Scheme for Large-Scale RDF Data in Distributed Environments

Min-Soo Kim,Jae-Yeol Park,Jin-Woo Song,Hyeon-Wook Jeon,Do-Jin Choi,Jongtae Lim,Kyoung-Soo Bok,Jae-Soo Yoo 한국콘텐츠학회 2016 한국콘텐츠학회 ICCC 논문집 Vol.2016 No.12

Change of Isometric Contractile Force and Muscle Activity Applying Heat according to the Time on Biceps Brachii Muscle

Jae Keun Jeon,Sang Soo Kim,Da Haeng Kang,Bo Kyoung Kim,Ja Pung Koo,Ok Kon Moon,Joon Hee Lee 국제물리치료학회 2013 Journal of International Academy of Physical Ther Vol.4 No.1

This study has investigated the effect of isometric contractile force and muscle activity applying sperficial heat according to the time from the biceps brachii muscle. In this study, 20 university students participants without musculoskeletal and neurological disorders. By applying a hot pack 5min, 10min, 20min and 30min respectively. After that measurement are skin temperature, contractile force and muscle activity. Skin temperature of the hot 5 min applied that rapidly changing. Increasing the time it takes to apply a variance has been reduced(p<.001). Isometric contractile force was not statistically significant but highest when applying the hot pack 5 minutes and lowest when applying the hot pack 30 minutes(p<.001). Muscle activity and median frequency was highest when applying the hot pack 5 minutes. To analyze the above results, it was found that isometric contractile force and muscle activity changed according to the applying time. These result lead us to the conclusion that this study will be more evidence for changes in muscle contraction to apply hot pack on clinic.

폐구균의 혈청형 분포와 항생제 감수성에 관한 연구

최경민,김정현,신경미,연수인,신전수,용동은,이경원,김동수,Choi, Kyoung-Min,Kim, Jeong-Hyun,Shin, Kyoung-Mi,Yeon, Soo-In,Shin, Jeon-Soo,Yong, Dong-Eun,Lee, Kyoung-Won,Kim, Dong-Soo 대한소아감염학회 2003 Pediatric Infection and Vaccine Vol.10 No.2

목 적 : 폐구균은 비인두에 존재하는 정상균주이나 중이염 등의 국소 감염 뿐 아니라 폐렴, 뇌수막염, 패혈증 등의 침습성 질환을 유발하는 것으로 알려져 있다. 최근 전 세계적으로 다제내성 폐구균이 증가하는 추세를 보여 큰 문제가 되고 있는바 이에 저자들은 폐구균의 혈청형과 항생제 감수성을 검사하고, 향후 시행될 폐구균 예방접종의 효용성 등을 예측해 보고자 하였다. 방 법 : 2001년 9월부터 2003년 1월까지 연세의료원에 내원한 환자 중 배양 검사상 폐구균이 검출된 116명을 대상으로 하였다. 폐구균의 혈청형 검사는 Quellung 반응을 통해 결정하였고, 페니실린 내성 여부는 oxacillin 디스크 확산법으로 판정하였다. 결 과 : 폐구균은 객담 76례(65.5%), 혈액 13례(11.2%), 이루 12례(10.3%), 인두 7례(6.0%), 비강 2례(1.7%), 뇌척수액, 안구분비물, 복수, 수술 후 창상부위, 두부 농양, 도관 각 1례(0.9%)로 총 116례에서 배양되었으며, 98례에서 혈청형 검사가 가능하였다. 분리된 혈청형을 살펴보면 19F 15례(15.3%), 19A 11례(11.2%), 11A 8례(8.2%), 6A, 14와 3이 각 7례(7.1%), 6B, 23F와 35가 각 6례(6.1%)의 순이었다. 총 116례 중 82례(70.7%)에서 페니실린 내성을 보였으며, 페니실린 내성균주의 혈청형은 19F, 19A, 11A, 23F, 6A, 9V등이 49례(59.8%)를 차지하였고, cotrimoxazole(74.4%), tetracycline(69.5%), erythromycin(90.3%) 등의 다른 항생제에도 높은 내성률을 보였다. 소아 환자 22례 중 20례에서 혈청형 분석이 가능하였고, 19A, 19F가 각 5례(25.0%), 6A, 6B, 23F가 각 2례(10.0%), 11A, 14, 19, 29가 각 1례(5.0%)를 차지하여 7가 폐구균 단백결합백신에 포함되는 혈청형이 50%(10/20), 백신관련 혈청형을 포함하여 85%(17/20)이었으며, 22례 중 86.4%(19/22)에서 페니실린 내성을 보였다. 결 론 : 이전의 보고에 비해 백신포함 혈청형의 빈도가 약간 낮은 소견을 보였으며, 최근 일부 폐구균 혈청형의 변화가 보고되고 있는 바 7가 폐구균 단백결합 백신의 상용화에 앞서 전국적인 폐구균 혈청형의 조사가 필요할 것으로 사료된다. Purpose : Streptococcus pneumoniae is part of the normal flora but is also responsible for causing many invasive diseases such as pneumonia, meningitis, and sepsis in addition to noninvasive diseases such as otitis in children. Multi-drug resistant strains has raised a lot of concern worldwide and thus the importance of prevention has been emphasized. We have analyzed the current serotypes and antibiotic sensitivity of each serotype as a baseline study to estimate the efficacy of the pneumococcal vaccine in Korean children. Methods : One hundred sixteen cases of pneumococcus cultured at Yonsei Medical Center from September 2001 to January 2003 were analyzed. The serotyping was done with the Quellung reaction and penicillin resistance was tested using the oxacillin disc diffusion method. Results : Pneumococcus were cultured from the sputum in 76 cases(65.5%), from the blood in 13 cases(11.2%), from the ear discharge in 12 cases(10.3%), from the throat in 7 cases(6.0%), from the nasal cavity in 2 cases(1.7%), and one case(0.9%) each from the cerebrospinal fluid, eye discharge, peritoneal fluid, post-operational wound, brain abscess, and catheter tip. Serotyping was possible with 98 cases and the following serotypes were found; 15 cases of type 19F(15.3%), 11 cases of 19A(11.2%), 8 cases of 11A(8.2%), 7 cases each of 6A, 14 and 3(7.1%), 6 cases each of 35, 6B and 23F(6.1%). Eighty two cases(70.7%) out of 116 cases were penicillin resistant and serotypes 19F, 19A, 11A, 23F, 6A, 9V constituted the majority, 48 cases(59.8%). These serotypes showed resistance to cotrimoxazole (74.4%), tetracycline(69.5%), and erythromycin(90.3%) as well. In the 22 cases cultured from children, 19A and 19F were found in 25.0%, 6A, 6B, and 23F in 10.0%, 11A, 14, 19, and 29 in 5.0%. Fifty percent(10/20) of the clinical isolates were represented in the current 7-valent pneumococcal protein conjugate vaccine, and 85%(17/20) when the cross-reacting serotypes were included. Penicillin resistance was found in 86.4%(19/22). Conclusion : The percentage of serotypes included in the 7 valent pneumococcal protein conjugate vaccine found in our study was 40.8% which was less than other prior studies. In anticipation of a change of pneumococcal serotypes, a nationwide multicenter study is needed before the initiation of pneumococcal vaccines in Korea.