http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
탄소섬유 적층혼성부재의 계면수 변화에 따른 축 압궤 특성
서현경,박준우,양용준,황우채,양인영 朝鮮大學校 機械技術硏究所 2007 機械技術硏究 Vol.10 No.1
알루미늄과 CFRP는 대표적인 경량화 재료이다. 알루미늄 부재는 안정적인 소성 변형에 의해 에너지를 흡수하며, CFRP 부재는 비강성과 비강도가 우수하고 불안정한 취성파괴로 인해 에너지를 흡수한다. 이러한 각각 알루미늄과 CFRP 부재의 압궤 특성을 기초로 두 재 료의 결합에 의해 서로의 장점에 대한 시너지 효과를 얻기 위해 혼성구조부재를 제작하였다. 본 연구에서는 알루미늄 부재의 외측을 CFRP로 강화시킨 혼성구조부채를 제작하여 CFRP의 계면수 변화에 따른 축 방향 준정적 압궤실험을 행하여 사각 및 원형 단변 모형의 혼성구조부재의 압궤 특성을 조사하였다. 실험 결과 혼성구조부재는 내부의 알루미늄 부재의 연성 성질 때문에 CFRP 부재의 불안정한 취성 파괴를 보완하여 비교적 안정적인 압궤 모드를 보였다. 하지만 혼성구조부재는 계면수 변화에 대해 에너지 흡수성과 압궤 모드는 별다른 영향을 보이지 않았다. The aluminum or CFRP is representative of light-weight materials. The aluminum tubes absorb energy by stable plastic deformation and the CFRP tubes absorbs energy by unstable brittle failure with higher specific strength and stiffness. Based on the respective collapse characteristics of aluminum and CFRP tubes, the aluminum CFRP compound tubes were manufactured to get a synergy effect when the aluminum CFRP tubes were combined with the advantages of each tube. This paper is to investigate the collapse characteristics of square or circular shaped aluminum CFRP compound tubes subjected to quasi-static axial collapse tests which were conducted by changing the stacking conditions. Test results showed that the collapse of the aluminum CFRP compound tubes complemented unstable brittle failure of the CFRP tube due to the ductile characteristics of the inner aluminum tube. It turned out that interlaminar numbers of aluminum CFRP compound tubes have no influence on the energy absorption and collapse modes of the tubes.
좌심실비후 환자에서 베타차단제의 급중단이 임상증상 및 좌심기능에 미치는 영향
황종현,김영태,배용학,임현주,조용근,채성철,전재은,박의현 慶北大學校 醫科大學 1997 慶北醫大誌 Vol.38 No.1
목적 : 베타 차단제와 칼슘 길항제의 장기투여로 안정상태에 있는 비후형 심근증이나 고혈압성좌심실비후 환자에서 이들 약제를 갑자기 중단하였을 때 혈역학, 심기능 및 임상상에 미치는 영향을 알아보기 위하여 본 연구를 시행하였다. 대상 및 방법 : 경북대학교 병원 순환기내과에서 통원치료중인 비후형 심근중 환자 5명과 심한좌심실비후를 동반한 고혈압 환자 6명(남자 6명, 여자 5명)을 대상으로 장기투여 중이던 베타 차단제와 칼슘 길항제를 최소 5일 중단한 후 임상증상, 혈압 및 심박수의 변동, 그리고 투약중지 전후에 도플러 심초음파도를 기록하여 좌심실내경, 벽두께, 좌심실근량, 구혈율 및 승모판혈류속도곡선의 변화를 관찰하였다. 결과 : 1) 약물치료 중단 후, 베타차단제의 경우 9명 중 6명에서, 그리고 칼슘길항제 및 디소피라미드를 복용하던 각 1명, 도합 7명의 환자에서 심계항진, 호흡곤란의 악화, 흉통이 관찰되었고, 심계항진을 호소한 1예에서는 심방세동이 재발되었다. 2) 혈압, 심박수, 확장말기 및 수축말기 좌심실내경, 심실중격 및 심실후벽 두께, 좌심실근량 및 구혈을 모두는 치료약물 중단 전후에 다소 변화하였으나 유의하지 않았다. 3) E파 최고속도와 E파 시간속도적분은 약물투여 중단 전후에 유의한 변화는 없었으나, A파 최고속도와 A파 시간속도적분은 중단 후에 각각 유의하게 증가하였으며(both P<0.01), E/A 최고속도비와 E/A 시간속도적분비는 각각 유의하게 감소하였다(both P<0.01). 한편, E파 감속시간, 등용이완시간 그리고 A-Ar 간격[A파의 최고점에서 A reversal(Ar)파의 최저점간의 시간] 모두는 중단 후 유의한 변화가 없었다. 1 결론 : 비후형 심근증 이나 고혈압성 좌심실비후 환자에서 장기투여중이던 베타 차단제와 칼슘길항제를 일시적으로 중단하였을 때 임상중상의 악화와 더불어 확장기 기능의 변화를 초래하였다. 따라서 약물치료로 비록 임상적으로 안정상태에 있더라도 치료를 갑자기 중단할 때는 주의해야 할 것으로 생각된다. Objectives : This study was done to evaluate the changes in clinical findings, hemodynamics and cardiac function after abrupt withdrawal of longterm beta-blockers and/or calcium channel blockers in hemodynamically stable patients with hypertrophic cardiomyopathy and left ventricular(LV) hypertrophy associated with hypertension. Methods : Eleven patients with hypertrophic cardiomyopathy(n=5) and LV hypertrophy associated with hypertension(n=6) were studied. Symptom assessment, blood pressure, electrocardiography and echocardiography including pulsed Doppler examination were obtained before and at least 5 days after abrupt cessation of beta-blockers and calcium antagonists. Results : 1) Deterioration in symptoms(i.e. palpitation, aggravation of dyspnea and chest pain) was observed in seven patients after abrupt withdrawal. 2) There were no significant changes in blood pressure, heart rate, end-systolic and end-diastolic LV dimensions, interventricular septal thickness, LV posterior wall thickness, LV mass, and ejection fraction before and after drug withdrawal. 3) Doppler time intervals and E wave peak-velocity and time velocity integral(TVI) were not significantly changed before and after drug withdrawal. But A wave peak-velocity and TVI after abrupt withdrawal were significantly increased(both p<0.01), and E/A peak-velocity ratio and TVI ratio were significantly decreased(both p<0.01). Conclusions : These findings suggest that temporary omission of beta blockers and calcium channel blockers develops deterioration in symptoms and LV diastolic dysfunction in hypertrophic cardiomyopathy and LV hypertrophy associated with hypertension. Physicians should avoid abrupt withdrawal of longterm beta blockers in LV hypertrophy.
Metacercariocidal effects and infection status of Gymnophalloides seoi in oysters
Hyeon Cheol Kim,Eui Ju Hong,Si Yun Ryu,Joon Seok Chae,Jinho Park,Kyoung Seong Choi,Do Hyeon Yu,Bae Keun Park 한국예방수의학회 2019 예방수의학회지 Vol.43 No.2
We studied the infection rate of and various metacercariocidal approaches to controlling Gymnophalloides seoi for prevention of human infection in cultured and natural oysters in Korea. The selected survey areas were Aphae-do (Shinan-gun, Jeollanam-do), which is an endemic area for G. seoi, and Tongyeong (Geonsangnam-do), which is the main production area of oysters in Korea. In the Tongyeong area, the metacercariae of G. seoi were not detected in cultured oysters (0/201) or wild oysters (0/134). Seventy-two G. seoi metacercariae were observed in 33 of 265 natural oysters collected from Aphae-do; however, metacercariae were not detected in the cultured oysters (0/1101) purchased from the Daejeon Fish Market. To investigate the viability of G. seoi metacercariae, various metacercariocidal treatments were used with 3.5% saline and oyster juice used as positive controls. The metacercariae survived for 75.4 h in 3.5% saline and 112.6 h in oyster juice. After the metacercariocidal treatment, G. seoi metacercariae were survived for 13.29 min in tap water, < 20 sec in 4.3% vinegar, no effect in a rinse of the whole oyster body in 70°C water for 1 sec, but 1 sec in a rinse of the whole oyster body in 90°C water for 1 sec. The greatest metacercariocidal effect on G. seoi was from rinsing oysters in 90°C water followed by those from treatment with 20% ethyl alcohol, 4.3% vinegar, and tap water. However, we suggest that the most actual prevention to G. seoi human infection is rinsing the oysters with tap water for at least 30 min.
Ocular setariasis by Setaria digitata in a horse in Korea
( Hyeon-cheol Kim ),( Dong Choon Ahn ),( Jin Ho Park ),( Do-hyeon Yu ),( Joon-seok Chae ),( Jae-gyu Yoo ),( Cheol Ho Sim ),( Kyoung-seong Choi ),( Young-jae Park ),( Bae-keun Park ) 한국동물위생학회(구 한국가축위생학회) 2018 韓國家畜衛生學會誌 Vol.41 No.1
A three-year-old male Thoroughbred horse with corneal opacity in his left eye was donated to Chonbuk National University for anatomical study. Upon gross observation, two whitish parasites were moving swiftly within the vitreous chamber of the eyeball. The worms obtained from the eye after anatomical dissection were identified as Setaria digitata by morphological observation with light and scanning electron microscopes; one male (43 mm in length) and one female (55 mm) were found. This aberrant ocular infection by S. digitata is the first case reported in horses in Korea.
Ocular setariasis by Setaria digitata in a horse in Korea
Kim, Hyeon-Cheol,Ahn, Dong Choon,Park, Jin ho,Yu, Do-Hyeon,Chae, Joon-Seok,Yoo, Jae-Gyu,Sim, Cheol ho,Choi, Kyoung-Seong,Park, Young-Jae,Park, Bae-Keun The Korean Society of Veterinary Service 2018 韓國家畜衛生學會誌 Vol.41 No.1
A three-year-old male Thoroughbred horse with corneal opacity in his left eye was donated to Chonbuk National University for anatomical study. Upon gross observation, two whitish parasites were moving swiftly within the vitreous chamber of the eyeball. The worms obtained from the eye after anatomical dissection were identified as Setaria digitata by morphological observation with light and scanning electron microscopes; one male (43 mm in length) and one female (55 mm) were found. This aberrant ocular infection by S. digitata is the first case reported in horses in Korea.
An Experimental Study on Water Surface Profiles of High Froude Number Flows
Jae-Hyeon Park,Yong Sung Park,김영도,Dong Seok Chae 대한토목학회 2018 KSCE Journal of Civil Engineering Vol.22 No.8
Motivated by need to study supercritical overbank flows on floodplain, we experimentally investigate if initially supercritical flowin a rectangular flume would maintain its state throughout. Varying upstream gate opening, flow rate and angle of the slope, a total of37 experimental cases were carried out. The experimental results are compared to two existing theories: an inviscid theory based onnonlinear shallow water equations and jump conditions and a hydraulic theory that takes friction into account. The experimental dataare consistent with the two theories. Flows on downward slope were stable, while those on upward slope had unstable hydraulic jumpand transformed into subcritical flow. The reported results should serve well in designing a laboratory flume with the supercriticalinflow and in conducting hydraulic model experiments on overbank flows.