• 제목/요약/키워드: Slit hood

검색결과 4건 처리시간 0.024초

고속철도에서 슬릿커버 완충공의 터널 미기압파 저감성능 (Experimental Study on the Slit Cover Hood for Reducing the Micro Pressure Waves in High-Speed Train-Tunnel Interfaces)

  • 김동현;민동호
    • 대한기계학회논문집B
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    • 제25권6호
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    • pp.758-765
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    • 2001
  • Purpose of the present is to investigate the food configuration at a tunnel entrance for reducing the micro pressure wave that is generated according to train speed. Two configurations were examined for tunnel of 0.5 km length. The experimental results show that a slit cover hood installed at the entrance of the tunnel reduces the maximum micro pressure wave by 41.2%, and a configuration with a slit cover hood installed at the entrance and a 45$^{\circ}$slanted portal at the exit of the tunnel suppresses it by 47.7%.

300km/h급 고속철도의 터널 미기압파 저감을 위한 슬릿후드의 실험적 연구 (Experimental study on the alleviation of micro-pressure waves radiated from the tunnel exit with the slit hoods on the high-speed train operations of 300km/h)

  • 김동현;민동호
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2000년도 춘계학술대회논문집B
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    • pp.619-624
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    • 2000
  • The purpose of present study is to investigate for reducing micro pressure waves generated according to train speeds $(240km/h{\sim}380km/h)$ through tunnels with countermeasures as followings; the hood configuration in tunnel entrance. We developed hoods for tunnel of 0.5 km length in the condition of tunnel cross-section area of $107m^2$ on the slab track. According to the results the maximum micro-pressure wave is reduced by 41.2% for the slit hood installed at the entrance of the tunnel and reduced by 47.7% for the slit hood installed at the entrance of the tunnel and the $45^{\circ}$ slanted portal at the exit of the tunnel

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고속철도에서 슬릿커버후드의 터널 미기압파 저감성능에 관한 연구(II) (Experimental Study on the Slit Cover Hood for Reducing the Micro Pressure Waves in High-speed Train-tunnel Interfaces)

  • 김동현;신민호;한명식
    • 한국터널지하공간학회 논문집
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    • 제2권3호
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    • pp.3-11
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    • 2000
  • 본 연구의 목적은 고속철도 터널 입구에 슬릿 커버 후드를 적용하여, 고속열차 터널 진입시 터널 출구 쪽에서 방사되는 미기압파를 저감시키는데 있다. 경부고속철도 $107m^2$의 단면적을 갖는 슬라브 궤도 0.5 km 터널에 대하여 슬릿 커버 후드라는 구조물 대책을 마련하였다. 개발시험 결과는 터널 입구에만 후드를 설치했을 경우 미기압파가 최대 41.2 %가 저감되었으며, 터널 입구에 후드를 설치하고 출구에 $45^{\circ}$ 경사갱구를 설치했을 경우는 47.7 %가 저감되었다.

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"Letter-Box" Conjunctival Flap in a Dog with Severe Corneal Edema after Phacoemulsification

  • Sunhyo Kim;Dohyoung Kwon;Kangmoon Seo;Seonmi Kang
    • 한국임상수의학회지
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    • 제40권2호
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    • pp.152-157
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    • 2023
  • A two-year-old, spayed female, Bichon Frise, was referred for severe corneal edema and corneal ulcer in the left eye (OS). The cornea had gradually swelled over one week after phacoemulsification performed a month prior, and that was refractory to 5% sodium chloride eye drop instillation or temporary partial tarsorrhaphy. A complete ophthalmic examination was performed. Severe corneal edema with intrastromal bullae and moderate anterior chamber flare was found on slit-lamp biomicroscopy in the OS, which obstructed the fundus examination. Corneal thickness was measured using high-resolution ultrasound biomicroscopy. The thickness of the OS cornea was 2.74 mm. The "letter-box" conjunctival flap was planned. Dorsal and ventral superficial keratectomy followed by a hood conjunctival flap was performed. Topical and systemic antibiotics and 5% sodium chloride eye drops were prescribed. Decreased corneal thickness was observed at one week, two weeks, and two months postoperatively (1.53 mm, 1.32 mm, and 0.92 mm, respectively). There were no postoperative complications, such as ocular discomfort or recurrent corneal ulcers. The "letter-box" conjunctival flap, a type of superficial keratectomy and conjunctival advancement hood flap, effectively relieved the severe irreversible corneal edema. This could be a simple but effective surgical intervention for patients with endothelial cell damage especially after phacoemulsification.