• Title/Summary/Keyword: Puncture

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Voronoi Simulation on Puncture Phenomenon of ZnO Varistors (ZnO 바리스터의 평처 현상에 대한 보로노이 시뮬레이션)

  • Lee, Young-Jong;Hwang, Hui-Dong;Han, Se-Won;Kang, Hyung-Boo
    • Proceedings of the KIEE Conference
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    • 1998.07d
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    • pp.1282-1284
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    • 1998
  • ZnO Varistor is an electronic ceramic device for controlling the surge voltage from low level to high. In this study, the puncture mechanism occurring in ZnO varistor is investigated, and the simulation for restraining the puncture by formulating the relation between the applied voltage and the increase of the inside temperature of grain is applied. In order to simulate the cause of the current localization which is the primary factor causing the puncture, the localization phenomenon and the temperature distribution induced by the localized current, the Voronoi network is applied, which can realize the structure of the practical varistor better than the established simple network. Using the current through each grain and the voltage applied to the grain boundary obtained from that simulation, the Joule heating energy is calculated and the phenomenon that the puncture occurs can be analyzed quantitatively by simulating the electric and thermal characteristics according to the externally applied pulsed voltage.

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Rheological Properties of Acorn Flour Gels - Puncture Test and Back Extrusion Test - (도토리묵의 물리적 특성 -Puncture test 와 Back Extrusion test-)

  • Kim, Young-A;Rhee, Hei-Soo
    • Korean Journal of Food Science and Technology
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    • v.17 no.6
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    • pp.469-473
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    • 1985
  • The typical force-distance curves by puncture test and Back Extrusion test of acorn flour gels were investigated. Kc' and Ks' were calculated to estimate the compression and shear components of a puncture force. In this study, compression effect played a major role. The more concentration of acorn flour gel and diameter of probe increased, the more compression force contributed to the puncture force. In the Back Extrusion test, the effect of increasing the sample size was to extend the length of the plateau without affecting the maximum force. However, as the concentration of acorn flour gel increased, maximum Extrusion force became larger.

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Difference of Pain Depending on the Bed Rest Period after Lumbar Puncture in Patients with Leukemia (백혈병환자의 요추천자 후 침상안정시간에 따른 두통과 요통의 차이)

  • Jeong, Young-Nam;Lee, Hyang-Yeon;Park, Young-Mi
    • Journal of East-West Nursing Research
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    • v.14 no.1
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    • pp.36-43
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    • 2008
  • Purpose: This study was conducted for an evidence-based nursing intervention on bed rest period after puncture, by confirming whether there was a difference in scores of headache and back pain between the 1-hour bed rest group and the 6-hour bed rest group following lumbar puncture in patients with leukemia. Method: The subjects were 45 inpatients of the department of hematology at a general hospital in Seoul, from January 1 to March 31, 2005. There were 21 patients in the 1-hour bed rest group and 24 patients in the 6-hour bed rest group. A graphic rating scale was used to measure headaches and back pains. Collected data were analyzed with SPSS 12.0. Non- parametric statistics were used to analyze the data. Results: There was no significant difference between the 1-hour bed rest group and the 6-hour bed rest group in the headache level and back pain level. Conclusion: Therefore, it is considered that a long period of bed rest over 6 hours after lumbar puncture is not a necessary nursing intervention, and repeated studies are required to confirm the result.

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A Comparison of Tensile and Puncture Properties of Nonwoven Fabrics

  • Park, Tae-Y;Tushar K. Ghosh
    • Proceedings of the Korean Fiber Society Conference
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    • 1998.10a
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    • pp.283-285
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    • 1998
  • Although many papers have been published for the mechanical properties of nonwoven fabrics, there is no report on the relationship of tensile and puncture properties. For the further applications of lightweight nonwoven products like protective clothing materials, thorough understanding of the relationship should be preceded when they are subjective to puncture farce. [1,2] (omitted)

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Paradoxical Transtentorial Herniation Caused by Lumbar Puncture after Decompressive Craniectomy

  • Jung, Heyun-Jin;Kim, Dong-Min;Kim, Seok-Won
    • Journal of Korean Neurosurgical Society
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    • v.51 no.2
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    • pp.102-104
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    • 2012
  • Although decompressive craniectomy is an effective treatment for various situations of increased intracranial pressure, it may be accompanied by several complications. Paradoxical herniation is known as a rare complication of lumbar puncture in patients with decompressive craniectomy. A 38-year-old man underwent decompressive craniectomy for severe brain swelling. He remained neurologically stable for five weeks, but then showed mental deterioration right after a lumbar puncture which was performed to rule out meningitis. A brain computed tomographic scan revealed a marked midline shift. The patient responded to the Trendelenburg position and intravenous fluids, and he achieved full neurologic recovery after successive cranioplasty. The authors discuss the possible mechanism of this rare case with a review of the literature.

Roof tile frangibility and puncture of metal window shutters

  • Laboy-Rodriguez, Sylvia T.;Smith, Daniel;Gurley, Kurtis R.;Masters, Forrest J.
    • Wind and Structures
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    • v.17 no.2
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    • pp.185-202
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    • 2013
  • The goal of this study was to investigate the vulnerability of roof tile systems and metal shutters to roof tile debris. Three phases addressed the performance of tile roof systems and metal shutters impacted by roof tile debris. The first phase experimentally evaluated the tile fragment size and quantity generated by a tile striking a tile roof system. The second phase experimentally quantified the puncture vulnerability of common metal panel shutter systems as a function of tile fragment impact speed. The third phase provided context for interpretation of the experimental results through the use of a tile trajectory model. The results provide supporting evidence that while metal panel window shutters provide significant protection against a prevalent form of windborne debris, these systems are vulnerable to tile fragment puncture in design level tropical cyclones. These findings correlate with field observations made after Hurricane Charley (2004).

Traumatic Spinal Subdural Hematoma : Value of MRI (Fat Suppression Technique) and Spinal Puncture - 2 Cases Report - (외상성 요추 경막하 출혈 : MRI(Fat Suppression Technique)와 척추천자의 유용성 - 증례보고 -)

  • Park, Sang Hoon;Hyun, Dong Keun;Park, Chong Oon;Ha, Young Soo
    • Journal of Korean Neurosurgical Society
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    • v.29 no.6
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    • pp.810-814
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    • 2000
  • We report two cases of spinal subdural hematoma in the lumbar region after trauma. They developed in a 27-years old man and a 32-year-old woman. They had no other causes such as bleeding tendency, preexisting spinal lesions, lumbar puncture, vascular malformation and anticoagulant therapy. There lesions were diagnosed with MRI(fat suppression) and treated by lumbar puncture.

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Voronoi Simulation on the Puncture Phenomena of ZnO Varistors (ZnO 바리스터의 펑처 현상에 관한 보로노이 시뮬레이션)

  • Lee, Yeong-Jong;Hwang, Hwi-Dong;Han, Se-Won;Gang, Hyeong-Bu
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.48 no.2
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    • pp.109-116
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    • 1999
  • ZnO Varistor is an electronic ceramic device to absorb the surge voltage from low voltage to high. To investigate the puncture mechanism occurring in NnO varistor, the Voronoi simulation for formulating the relation between the applied voltage and the increase of the temperature inside grain is applied. The Voronoi network can realize the structure of the practical varistor better than the established simple network. Using the current through each grain and the voltage applied to the grain, Joule heating energy is calculated and the phenomenon that the puncture occurs can be analyzed quantitatively by simulating the electric and thermal characteristics according to the externally applied pulsed voltage.

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Headache and Pneumocephalus after Lumbar Epidural Block -A case report- (요부 경막외 차단후 발생한 두통 및 기뇌증 -증례 보고-)

  • Han, Chan-Soo;Yu, Jin-Sup;Kim, Il-Ho;Kim, Yu-Jae;Kim, Chun-Sook;Ahn, Ki-Rhyang
    • The Korean Journal of Pain
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    • v.9 no.1
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    • pp.251-255
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    • 1996
  • Headache after epidural block is the most frequent result of an unintentional dural puncture. This form of headache is usually caused by cerebrospinal fluid leakage through the dural puncture site. Another proposed cause of postdural puncture headache is the unintentional injection of air into the subarachnoid space. We experienced a case of severe headache with a patient after lumbar epidural block and discovered air in the intracranial subarachnoid space(pneumocephalus) with the aid of brain computerized tomography.

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Development of Postdural Puncture Headache Following Therapeutic Acupuncture Using a Long Acupuncture Needle

  • Jo, Dae-Jean;Lee, Bong-Jae;Sung, Joon-Kyung;Yi, Jae-Woo
    • Journal of Korean Neurosurgical Society
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    • v.47 no.2
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    • pp.140-142
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    • 2010
  • Acupuncture appears to be a clinically effective treatment for acute and chronic pain. A considerable amount of research has been conducted to evaluate the role that acupuncture plays in pain suppression; however, few studies have been conducted to evaluate the side effects of the acupuncture procedure. This case report describes a suspected postdural puncture headache following acupuncture for lower back pain. Considering the high opening pressure, cerebrospinal fluid leakage, and the patient's history of acupuncture in the lower back area, our diagnosis was iatrogenic postdural puncture headache. Full relief of the headache was achieved after administration of an epidural blood patch.