• Magazine of the Korean Society of Agricultural Engineers
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• v.34 no.E
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• pp.45-59
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• 1992

At downstream part of the hydraulic structures such as spiliway or drainage gate, jet flow can occur by gate opening. If stream bed is not hard or bed protection is not sufficient, scour hole will be formed due to high shear stress of the jet flow. We call this primary scour. Once the scour hole is formed, a vortex occurs in it and this vortex causes additional scour. We call this secondary scour. The primary scour proceeds to downstream together with flow direction but the secondary one proceeds to upstream direction opposite to it. If the secondary one continues and reaches to the hydraulic structure, it can undermine the bottom of hydraulic structure and this will lead to failure of structure itself. Thus, it is necessary to know the physical features of the vortex structure in a scour hole, which is the main mechanism of the secondary scour. This study deals with the characteristics of the vortex structure and its shear stress which causes the secondary scour.

• Proceedings of the KAIS Fall Conference
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• 2011.12a
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• pp.326-329
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• 2011

Mortality associated with maxillofacial infection is relatively low due to the development of antibiotics, and improved oral care. However, inappropriate treatment, delayed treatment, old age, underlying systemic disease, and drug-resistant micro-organisms can potentially result in life threatening situations such as cavernous sinus thrombosis, mediastinitis, and sepsis. Sepsis is the most dangerous state with high mortality, ranging from 20~60%. The treatment of sepsis involves properly monitoring vital functions, fluid resuscitation, surgical drainage, and empirical use of high doses of antibiotics until culture results are available. Ventilatory support maybe be required as well. We encountered a 64-year-old patient who died from sepsis that developed as the result of an odontogenic infection. The initial diagnosis was right temporal, infraorbital, buccal, pterygomandibular space abscess. Despite surgical and medical supportive care, the condition progressed to sepsis and after four days the patient died due to multiple organ failure.

• Neurospine
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• v.15 no.4
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• pp.394-399
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• 2018

Subarachnoid pleural fistula (SPF) is an aberrant communication between the pleural cavity and subarachnoid space, resulting in uncontrolled cerebrospinal fluid drainage. The negative pressure of the pleural cavity creates a continuous suctioning effect, thereby impeding the spontaneous closure of these fistulas. Dural tears or punctures in cardiothoracic procedures, spinal operations, and trauma are known to cause such abnormal communications. Failure to recognize this entity may result in sudden neurological or respiratory complications. Hence, a high index of suspicion is required for early diagnosis and prompt management. Noninvasive positive pressure ventilation has been described to be effective in managing such fistulas, thus mitigating the high morbidity associated with exploratory surgery for primary repair. Herein, we describe the typical presentation of SPF and the clinical course, treatment, and follow-up of a patient who sustained SPF following anterior thoracic spinal surgery.

• Journal of Chest Surgery
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• v.52 no.2
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• pp.109-111
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• 2019

We report the case of a female patient who underwent late reoperation following endocarditis surgery. The patient first underwent surgery at 22 years of age for endocarditis with aortic and tricuspid insufficiency. She underwent aortic root replacement with a homograft and tricuspid valve replacement with a tissue valve. Coronary artery bypass using the internal thoracic artery and ligation of the left main coronary artery were performed. Ten years later, failure of the homograft and the tricuspid valve developed. In the second operation, the patient underwent a successful Bentall operation and tricuspid valve replacement with a mechanical valve under deep hypothermia and retrograde cold cardioplegia without drainage.

• Journal of Korean Society of Forest Science
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• v.105 no.4
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• pp.449-455
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• 2016

This study was conducted to provide the basic policy information for systematic forest road planning and maintenance management by surveying two different administrator groups. The survey results showed that the high priorities of forest road planning were silviculture, disaster prevention, and timber harvesting, and main forest road type was preferred for future use. Also 92.9% of the respondents expressed difficulties due to insufficient manpower and budget. The expected damage types due to forest road construction were threat-to-life by slope failure and dispute on crossing private land. The current main maintenance tasks on forest roads included drainage and road surface maintenance works. Main forest road facilities that should be needed after the construction were installation of additional drainage structures, and slope revegetation and stabilization.

• Journal of the Korean Association of Geographic Information Studies
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• v.9 no.2
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• pp.115-126
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• 2006

The purpose of this study is to develop an urban inundation model using GIS(geographic information system). The model is combining a storm sewer system model and a overland-flow model for the estimation inundation depth in urban area caused by the surcharge of storm sewers. SWMM(storm water management model) was employed to resolve the storm sewer flow and to provide the overflow hydrographs caused by the failure of a drainage system due to the shortage of drainage capacity. The level-pool overland-flow model and DEM based overland-flow model were used to calculate the detail inundation zones and depths due to the surcharge on overland surface. The simulation results can help the decision preventing flood damages by redesigning and enlarging the capacities of storm sewer systems in the inundation-prone areas. The model can also be applied to make the potential inundation area map and establish flood-mitigation measures as a part of the decision support system for flood control authority.

• Pediatric Infection and Vaccine
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• v.8 no.1
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• pp.107-113
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• 2001

Spinal epidural abscess(SEA) is a rare condition in children. Classic symptoms are spinal ache, root pain, weakness and paralysis. The earliest symptoms of SEA in the pediatric age group are nonspecific and variable. Early diagnosis may be almost impossible when local spinal pain is inconspicuous or absent, when toxic epiphenomena divert attention from subtle signs of neurologic dysfunction and when the patient is an acutely distressed and uncooperative child. Failure to diagnosis and treat condition on a timely basis may lead to permanent neurolgic dysfunction or even death. This infection, usually located in the dorsal epidural space of the mid thoracic or lower lumbar regions, is the result of hematogenous dissemination of bacteria, usually Staphylococci, from foci of infection in the skin, or respiratory or urinary tracts. MRI was the diagnostic method of choice. A combination of antibiotics and surgical drainage remains the treatment of choice. Prognosis is excellent if surgery is performed before the development of neurologic deficit. We report a case of SEA in a child whose first presenting symptom was abdominal pain rather than spinal pain. A case is diagnosed by MRI and successfully treated with laminectomy and drainage and antibiotics.

• The Journal of Engineering Geology
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• v.17 no.3
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• pp.339-350
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• 2007

Content, swelling, concentration, drainage of clay are critical factors that could control rock failures as well as discontinuous geological structures like faults and joints. Especially, the proportional components of clay minerals can be one of few direct indicators to a rock failure caused well by rainfall. Criticality of the role of clay mineral contents gets bigger in the slope and tunnel design. This study, using a horizontal boring core of pelitic/psammitic phyllite from the OO tunnel construction site, aims to investigate mineral composition changes related to fault distribution and their mechanical effects to the activity of these discontinuous layers (i.e., clay-filled fault layers), and eventually to define correlation among rock compositions, weathering products and rock instabilities. Field survey and lab tests were carried out for the composition and strength index of fault clay minerals within the core samples and microscopic analysis of fresh and weathered rock samples.

• Korean Journal of Bronchoesophagology
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• v.13 no.1
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• pp.19-22
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• 2007

Background and Objectives: The Objective of this study was to compare the effectiveness of the needle aspiration method and the I&D method in the treatment of peritonsillar abscess. Materials and Methods: A prospective clinical study was performed on 83 patients. All the patients were hospitalized after random treatment with either I&D or needle aspiration alone, received the same intravenous antibiotic therapy. Among the 83 patients, 73 patients who could be observed for longer than 6 months and had not undergone a tonsillectomy during the follow-up period, were analyzed for treatment outcomes. Results: There was no statistically significant difference in the initial failure rate(p=0.572), the hospitalized days(p=0.956), the recurrence rate(p=0.531) for the needle aspiration(35 patients) and I&D groups(38 patients). But, The mean duration of fever were statistically different in the needle aspiration(1.51 hours) and I&D groups(3.05 hours) (p=0.031). Conclusion: Two methods are thought to be similar in effectiveness, except that duration of fever was longer in the I&D group than in the needle aspiration group. However, taking advantages of the needle aspiration method into consideration, the needle aspiration of peritonsillar abscess may be more appropriate than I&D as an initial method for peritonsillar abscess

• Magazine of the Korean Society of Agricultural Engineers
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• v.37 no.3_4
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• pp.61-71
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• 1995

Natural ground is a composite consisted of the three phases of water, air and soil paircies. Among the three components, water as a material is weU understood but soil particles are not in foundation engineering. Especially, weathered granite soil generally shows a large volumetric expansion when they freeze. And, the stability and durability of the soil have shown decreased with repetitive freezing and thawing processes. These unique charcteristics may cause various construction and management problems if the soil is used as a construction material and foundation layers. This project was initiated to investigate the soil's physical and engineering characteristics resulting from freezing and freezing-thawing processes. Research results may be used as a basic data in solving various problems related to the soil's unique characteristics. The following conclusions were obtained: The degree of decomposition of weathered granite soil in Kangwon-do was very different between the West and East sides of the divide of the Dae-Kwan Ryung. Soil particles distributed wide from very coarse to fine particles. Consistency could be predicted with a function of P200 as LL=0.8 P200+20. Permeability ranged from 10-2 to 10-4cm/sec, moisture content from 15 to 20% and maximum dry density from 1.55 to 1.73 g /cmΥ$^3$ By compaction, soil particles easily crushed, D50 of soil particles decreased and specific surface significantly increased. Shear characteristics varied wide depending on the disturbance of soil. Strain characteristics influenced the soil's dynamic behviour. Elastic failure mode was observed if strain was less than 1O-4/s and plastic failure mode was observed if strain was more than 10-2/s. The elastic wave velocity in the soil rapidly increased if dry density became larger than 1.5 g /cm$^3$ and these values were Vp=250, Vg= 150, respectively. Frost heave ratio was the highest around 0 $^{\circ}C$ and the maximum frost heave pressure was observed when deformation ratio was less than 10% which was the stability state of soil freezing. The state had no relation with frost depth. Over freezing process was observed when drainage or suction freezing process was undergone. Drainage freezing process was observed if freezing velocity was high under confined pressure and suction frost process was occurred if the velocity was low under the same confined process.