• Title/Summary/Keyword: Acute angle

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Parabolic Wave Equations Based on $Pad{\acute{e}}$ Approximants - Model Applicable to Incidence Angle $80^{\circ}$ ($Pad{\acute{e}}$ 근사에 의한 포물형 파랑 근사식 - 입사각 $80^{\circ}$까지 적용 모형)

  • Seo, Seung-Nam
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.19 no.4
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    • pp.375-384
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    • 2007
  • Parabolic approximation wave models based on $Pad{\acute{e}}$ approximants are presented of which the $Pad{\acute{e}}$(15, 15) is shown to be applicable to incidence angle $80^{\circ}$ in comparison with the exact solution of a constant sloping bed. After introducing a systematic way of the derivation to the parabolic wave equation, parabolic models are obtained in this study upto the 15th order and several numerical results are given to wave transformation in a constant sloping bed.

The Effect of the Diameter and Anastomotic Angle on the Compliance and the Stress Distribution of the End-to-side Anastomosis. (직경 및 문합각도가 단측 문합의 컴플라이언스 및 응력분포에 미치는 영향)

  • 한근조;김영호
    • Journal of Biomedical Engineering Research
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    • v.19 no.2
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    • pp.183-188
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    • 1998
  • Von Mises stress and compliance distribution was evaluated using a finite element analysis on the end-to-side anastomosis of an artery with length of 20-24mm, inner diameter of 4mm, thickness of 0.5mm and a PTFE graft with length of 10mm, inner diameter of 2mm, thickness of 0.2mm when the anastomotic angle was taken from 30$^{\circ}$~90$^{\circ}$ in every 10$^{\circ}$ and the diameter ratio from 0.1-1 in every 0.1. The inner pressure of 1330 dyne/$\textrm{mm}^2$ was applied inside the 2 conduits. It was found that the compliance whose magnitude is larger on the acute angle anastomotic side than on the abtuse angle side became larger as the anastomotic angle became smaller and the diameter ratio larger and that the equivalent stress on the acute angle anastomotic side was larger than that on the abtuse angle side and became larger as the anastomotic angle and the diameter ratio became larger.

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The Effect of Postural Correction and Subsequent Balloon Inflation in Deformity Correction of Acute Osteoporotic Vertebral Fractures

  • Liu, Hai-Xiao;Xu, Cong;Shang, Ping;Shen, Yue;Xu, Hua-Zi
    • Journal of Korean Neurosurgical Society
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    • v.55 no.6
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    • pp.337-342
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    • 2014
  • Objective : To determine deformity correction by postural correction and subsequent balloon inflation in acute vertebral compression fractures (OVCFs) and to examine the effect of bone mineral density on deformity correction. Methods : A totol of 50 acute OVCFs received balloon kyphoplasty. Lateral radiographs were taken and analyzed at five different time points : 1) preoperative, 2) after placing the patient in prone hyperextended position, 3) after balloon inflation, 4) after deposition of the cement, and 5) postoperative. All fractures were analyzed for height restoration of anterior (Ha), middle (Hm) and posterior (Hp) vertebra as well as Cobb angle and Kyphotic angle. The bone mineral density (BMD) of lumbar spine was measured by dual-energy X-ray absorptiometry. According to the T-score, the patients were divided into two groups which were osteoporosis group and osteopenia group. Results : Postoperative measurements of Ha, Hm and the Cobb angle demonstrated significant reduction of 4.62 mm, 3.66 mm and $5.34^{\circ}$ compared with the preoperative measurements, respectively (each p<0.05). Postural correction significantly increased Ha by 5.51 mm, Hm by 4.35 mm and improved the Cobb angle by $8.32^{\circ}$ (each p<0.05). Balloon inflation did not demonstrate a significant improvement of Ha, Hm or the Cobb angle compared with baseline prone hyperextended. Postural correction led to greater improvements of Ha, Hm and Cobb angle in osteoporosis group than osteopenia group (each p<0.05). Conclusion : In acute OVCFs, the height restoration was mainly attributed to postural correction rather than deformity correction by balloon inflation. BMD affected deformity correction in the process of postural correction.

Study on the Development of Sintered Carbide Roller Mold for Reflector(1st) -Analysis of Reflector Geometry and Design of Acute Angle Diamond Wheel System- (반사체 회전금형 초경로울러의 개발에 관한 연구(제1보) -반사체 형상 해석 및 다이 아몬드 예각지석 시스템 설계-)

  • 김정두
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.5 no.2
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    • pp.73-82
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    • 1996
  • A simtered carbide roller mold for reflector which is used for coverof automobile lamp and beacon plate of highway has been developed. The geometry of sintered carbide roller mold has been determined from the analysis of reflector geometry. An acute angle diamond wheel and dressing system also has been designed and developed to manufacture the sintered carbide roller mold.

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Acute Angle Etching of silicon Dioxide Layer (이산화실리콘 층의 예각부식)

  • 최연익
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.22 no.4
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    • pp.84-91
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    • 1985
  • Acute angle etching Process of thermally grown silicon dioxide layer has been Proposed by depositing a thin layer of silicafilm on the thermal oxide layer. As densification temper-ature of silicafilm is varied from 175$^{\circ}C$ to 1,15$0^{\circ}C$, taper angles from 3$^{\circ}$ to 40$^{\circ}$ are ob-tained. Analytical model of the acute angle etching process has also been presented and etched profile equations of the silicon dioxide layer have been derived using format's principle of lease time. Etched profiles obtained from scanning electron microscope analysis show good agreement with the theoretically calculated profiles.

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Study on the Development of Sintered Carbide Roller Mold for Reflector -Analysis of Reflector Geometry and Design of Acute Angle Diamond Wheel System (반사체 회전금형 초경로울러의 개발에 관한 연구(제1보) -반사체 형상 해석 및 다이 아몬드 예각지석 시스템 설계-)

  • 김동식
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 1996.03a
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    • pp.170-176
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    • 1996
  • A Sintered carbide roller mold for reflectors which is used for cover of automobile lamp and beacon plate of highway has been developed. The geometry of sintered carbide roller mold has been determined from the analysis of reflector geometry. An acute angle diamond wheel and dressing system also has been designed and developed to manufacture the sintered carbide roller mold.

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Five Case Reports on Acute Neck Pain Patients with Abnormal Cervical Curvature Using Chuna Manual Therapy (추나요법으로 호전된 급성 경항통을 동반한 경추 만곡이상에 대한 증례보고 5례)

  • Yeong-Sang Kim;Su-Hyeon Jeong
    • The Journal of Churna Manual Medicine for Spine and Nerves
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    • v.18 no.2
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    • pp.65-73
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    • 2023
  • Objectives This case study aimed to investigate efficacy of Chuna manual therapy (CMT) on acute neck pain patients with abnormal cervical curvature. Methods CMT was administered to five patients with abnoraml cervical curvature in the Department of Korean Medicine Rehabilitation, College of Korean Medicine, Semyung University Korean Hospital from June 2018 to May 2023. Cervical angle, Jackson's angle, Jochumsen method, Ishihara index and visual analog scale (VAS) scores were evaluated before and after treatment. Results In cases 1, 2, 3, 4, and 5, the cervical angle, Jackson's angle, Jochumsen method, Ishihara index all increased, while VAS scores decreased after CMT. Conclusions The observed improvements suggest that CMT is effective in restoring the cervical curvature and alleviating neck pain in patients with acute neck pain.

Traumatic Acute Subdural Hematoma Extending from the Posterior Cranial Fossa to the Cerebellopontine Angle

  • Gulsen, Salih;Sonmez, Erkin;Yilmaz, Cem;Altinors, Nur
    • Journal of Korean Neurosurgical Society
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    • v.46 no.3
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    • pp.277-280
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    • 2009
  • Posterior cranial fossa subdural hematomas and extension of the subdural hematoma to the cerebellopontine angle is rarely seen and the concurrent development of acute peripheral facial palsy and the management strategy have not previously been reported in this pathology because of its rarity. We present this case to emphasize that minor head trauma may lead to a posterior cranial fossa hematoma extending to the cerebellopontine angle and cause peripheral facial palsy in patients using aspirin (acetylsalicylic acid). In addition, partial evacuation and waiting for the resorption of the hematoma may help to prevent damage to the 7th and 8th cranial nerves.

Results of Early Primary Repair for Acute Severe Ankle Sprains (급성 족관절 고도 염좌에 대한 조기 일차 봉합술 결과)

  • Jeong, Un-Seob;Park, Yong-Wook;Lee, Jae-Hyung
    • Journal of Korean Foot and Ankle Society
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    • v.10 no.2
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    • pp.173-178
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    • 2006
  • Purpose: The purpose of this study is to assess the clinical and radiological results of the early primary repair for acute ankle sprains. Materials and Methods: From October 2002 to September 2005, nine patients with acute ankle sprain were analyzed. Among them, eight patients took the inversion stress X-ray at local clinics, and the mean talar tilting angle was 28 degrees. We observed avulsion fragment near lateral malleolus in the other. The average age at the time of operation was 24 years and average follow-up period was 29 months. We evaluated postoperative symptoms by Hasegawa's clinical rating system, postoperative complications, and compared the talar tilting angle and anterior draw distance between both ankles at the final follow-up X-rays. Results: Anterior talofibular ligament was ruptured at fibula in 4, at midsubstance in 3, at talus in 1 and at fibula and midsubstance simultaneously in 1. Calcaneofibular ligament was ruptured at fibula in 3 including a case of avulsion fracture, at midsubstance in 2, and at calcaneus in 4. And posterior talofibular ligament was ruptured at midsubstance in 2. Clinical results were rated as excellent in all. We did not find major postoperative complications except for one sural nerve irritation. Both (injured ankle/uninjured ankle) talar tilting angle averaged 6.8/8.2 degrees and anterior draw distance averaged 2.9/3.7 mm at final follow-up X-rays. Conclusion: Early primary repair is recommended for treating acute severe ankle sprains and in case found avulsion fracture in X-ray taken after ankle sprain.

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Conditions for Moire Free Contact-Type 3 Dimensional Displays

  • Song, Yoon-Chul;Saveljev, Vladimir V.;Son, Jung-Young;Yeom, Seok-Won;Vashpanov, Yu. A.
    • Journal of the Optical Society of Korea
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    • v.12 no.2
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    • pp.93-97
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    • 2008
  • The superposing angle of the viewing zone forming optics and the display panel in the contact type 3 dimensional imaging systems for minimizing $moir{\acute{e}}s$ is found for a rectangular shape pixel with different aspect ratios. The angles are $26.2609^{\circ}$ for square shape pixels and $13.9858^{\circ}$ for the rectangular with aspect ratio 2. These angles result in the $moir{\acute{e}}s$ with the smallest period for the respective aspect ratio. The effectiveness of the angles is also experimentally demonstrated.