• Title/Summary/Keyword: Slit hood

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

  • Kim, Dong-Hyeon;Min, Dong-Ho
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.25 no.6
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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%.

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 (300km/h급 고속철도의 터널 미기압파 저감을 위한 슬릿후드의 실험적 연구)

  • Kim, Dong-Hyeon;Min, Dong-Ho
    • Proceedings of the KSME Conference
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    • 2000.04b
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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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Experimental Study on the Slit Cover Hood for Reducing the Micro Pressure Waves in High-speed Train-tunnel Interfaces (고속철도에서 슬릿커버후드의 터널 미기압파 저감성능에 관한 연구(II))

  • Kim, Dong-Hyeon;Shin, Min-Ho;Han, Myeong Sik
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.2 no.3
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    • pp.3-11
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    • 2000
  • Purpose of this paper is to investigate the hood configuration at a tunnel entrance to reduce the micro pressure wave that is generated according to train speed. Two configurations were examined for the tunnel of 0.5 km in 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 the configuration with a slit cover hood installed at the entrance and the $45^{\circ}$ slanted portal at the exit of the tunnel suppress the pressure wave by 47.7%.

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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
    • Journal of Veterinary Clinics
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    • v.40 no.2
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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.