• Journal of Korean Neurosurgical Society
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• v.44 no.3
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• pp.146-150
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• 2008

Objective : The authors reviewed the experience of 19 patients with orbital tumors and summarize the clinical features, surgical treatment and outcomes. Methods : The authors searched the database for all patients who underwent surgery for the treatment of orbital tumors at a single institution between 1999 and 2007. Data from clinical notes, surgical reports, and radiological findings were obtained for the analysis. Results : Orbital tumors constituted a heterogenous array of histopathology. The presenting symptoms were exophthalmos (52.6%), visual disturbance (26.3%) and pain (21.1%). The surgical approaches used were transcranial in 17 patients. Tumors located in the intraconal or perioptic space were surgically excised using a frontoorbital approach (8 cases). while pterional (3 cases). orbital (2 cases) and combined approaches (6 cases) were used for tumors in other sites. Total resection of tumors was achieved in 12 of 19 patients. In 4 patients with glioma and lymphoma only diagnostic biopsy was done. Three patients experienced visual deterioration postoperatively. Two patients had temporary diplopia, and one patient had temporary ptosis. Conclusion : Surgical treatment could be the mainstay of therapy for the majority of symptomatic orbital tumors. Many orbital tumors can be treated safely via a transcranial approach. Frontoorbital approach allows the surgeon to reach both the intraorbital and intracranial structures. Knowledge of the microanatomy of the orbit and meticulous surgical skills are necessary to overcome the pitfalls of intraorbital surgery.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.253.2-253.2
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• 2014

Micro hollow cathode discharges (MHCDs) are high-pressure, non-equilibrium discharges. Those MHCDs are useful to produce an excimer radiation. A major advantage of excimer sources is their high internal efficiency which may reach values up to 40% when operated under optimum conditions. To produce strong excimer radiation, the optimisation of the discharge conditions however needs a detailed knowledge of the properties of the discharge plasma itself. The electron density and temperature influence the excitation as well as plasma chemistry reactions and the gas temperature plays a major role as a significant energy loss process limiting efficiency of excimer radiation. Most of the recent spectroscopic investigations are focusing on the ultraviolet or vacuum ultraviolet range for direct detection of the excimer. In our experiments we have concentrated on investigating the micro hollow cathodes from the near UV to the near infrared (300~850 nm) to measure the basic plasma parameters using standard plasma diagnostic techniques such as stark broadening for electron density and the relative line intensity method for electron temperature. Finally, the neutral gas temperature was measured by means of the vibrational rotational structures of the second positive system of nitrogen.

• The Journal of Korean Institute for Practical Engineering Education
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• v.2 no.2
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• pp.74-82
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• 2010

As the basic knowledge during designing most moving mechanical structures, vibration engineering is a subject teaching the theory on vibration control and isolation, which also cultivating the ability of analyze variety of vibration problems. However, vibration engineering is more difficult to understand than other dynamics courses in mechanical field, so the development of educational equipments in order to help understanding physical theory of vibration is really necessary. So in this paper we could see the effect after doing simple experiment process using the educational vibration equipment with multiple function, students could easily understand physical theory of vibration. The educational vibration equipment with multiple function and its application range are introduced, which could performance four kinds of typical vibration phenomenon: vibration of multidegree of freedom system, vibration of beam, vibration of beam, and vibration of plate. Finally, assessments of response and improvement plan are proposed through a survey.

• The Korean Journal of Pain
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• v.19 no.2
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• pp.146-151
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• 2006

Background: Spinal cord stimulation is a well-established method for the management of several types of chronic and intractable pain. This form of stimulation elicits a tingling sensation (paresthesia) in the corresponding dermatomes. The goal of this study was to establish a correlation between the spinal levels of the implanted epidural electrodes and the paresthesia elicited due to stimulation of the neural structures. Methods: Thirty five patients, who received trial spinal cord stimulation, were evaluated. After the insertion of the lead to the selected position, the areas of paresthesia evoked by stimulation were evaluated. Results: Seventy-one percent of cases showed paresthesia in the shoulder area when the tip of the electrode was located between the C2⁣-C4 levels. At the upper extremities, paresthesia was evoked in 86⁣-93% of cases, regardless of the location of the electrode tip within the cervical spinal segments. The most common tip placement of the leads eliciting hand stimulation was at the C5 level. The most common level of electrode tip placement eliciting paresthesia of the anterior and posterior thigh and the foot were at the T7-⁣T12, T10⁣-L1 and T11-⁣L1 vertebral segments, respectively. Conclusions: Detailed knowledge of the patterns of stimulation induced paresthesia in relation to the spine level of the implanted electrodes has allowed the more consistent and successful placement of epidural electrodes at the desired spine level.

• Journal of the Korean Society for information Management
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• v.18 no.2
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• pp.231-254
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• 2001

As contemporary thesauri have become large and complex, it is increasingly difficult to assess the intended meaning of each one of the terms. Thereby the meaning of many descriptors seems to be very similar, and it is often not possible to distinguish among them and to identify the term correctly. Purpose of this article is to induce definitions of descriptors in thesaurus by specifying the characteristics of each concept, locating it in the domain and providing clear and prescriptive information on the meaning of each descriptor in the form of a standardized terminological definition. In this study, a small prototype thesaurus using definition of term in the field of information industry in Korean Standards has been developed. In this thesaurus definitions are written for each descriptor with the help of a proposed defining model and in accordance with defining rules borrowed from the field of terminology. In addition, elements of analyzed definition have been included in the relation structure of descriptors. It is revealed that terminological definition added to thesaurus may permit extraction of separate items of information from definitions for the representation of knowledge structures and makes it easier to confine the scope of descriptors to be included in thesaurus in a given subject field.

• Clinical and Experimental Pediatrics
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• v.58 no.9
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• pp.354-357
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• 2015

Parry-Romberg syndrome (PRS) is a rare, acquired disorder characterized by progressive unilateral facial atrophy of the skin, soft tissue, muscles, and underlying bony structures that may be preceded by cutaneous induration. It is sometimes accompanied by ipsilateral brain lesions and neurological symptoms. Here we present the case of a 10-year-old girl with right-sided PRS and recurrent monoplegic ataxia of the left leg. At 4 years of age, she presented with localized scleroderma over the right parietal region of her scalp; her face gradually became asymmetric as her right cheek atrophied. Brain magnetic resonance imaging revealed hemiatrophy of the face and skull base, and T2-weighted images showed increased signal in the right hemipons and hemicerebellar peduncle. Magnetic resonance angiography findings were unremarkable. She was treated with oral prednisolone, and her recurrent gait ataxia diminished within 2 months of the follow-up period. To the best of our knowledge, this is only the second case of PRS presenting with an abnormal involvement of the ipsilateral hemipons.

• The Journal of Engineering Geology
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• v.10 no.2
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• pp.36-51
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• 2000

Almost every year, Korean suffered from the repetitive natural disasters such as typhoons and floods. During last 10 years, Korea experienced annual average of $50 million property damages caused by inundation. To estabilish the flood disaster counter plan, knowledge for flood damage causes based on the field investigations of inundated area is required. The field investigations is focused on technique to document and analyze the meteorological conditions leading to torrential rains, the causes and patterns of flooding, the performance of flood control structures in affected areas, the extent damages and the effectiveness of local emergency response and recovery actions. We did comparative analysis of field investigation techniques. As a major goal of flood hazard map design, one of non structural disaster countermeasures, it was expected to reduce flood damage losses by requiring local governments to implement land-use regulation that would result in safe building practices in flood hazard areas. This requires local governments to develop flood hazard maps to assess how to manage particularly vulnerable floodplain areas. In this study we suggested a design manual and the management system of flood hazard map.

• Journal of Elementary Mathematics Education in Korea
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• v.23 no.4
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• pp.459-479
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• 2019

The purpose of this study is to explore the research trends and knowledge structures of 『Journal of Elementary Mathematics Education in Korea』 by applying the keyword network analysis. To do this, we analyzed the frequency of the occurrence of keywords in the journal and conducted keyword network analysis using the Krkwic program and NodeXL program. The results of the analysis are as follows. Firstly, 749 keywords were extracted from keyword cleansing process and 48 keywords, including mathematics curriculum, mathematics textbooks, school mathematics, mathematical problem solving, mathematically gifted student, etc. appeared more than five times. Secondly, the keyword network analysis showed that the keywords-mathematics textbooks, school mathematics, mathematical problem solving, mathematical communications-have high connection centrality. Finally, we provided the limitations of this study and suggested future research.

• Communications of Mathematical Education
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• v.32 no.1
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• pp.37-57
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• 2018

In the early days, the use of concept maps in mathematics education focused on how to represent mathematical ideas in the concept map. In recent years, however, concept maps have proved beneficial for improving problem solving ability. Conceptual diagrams can be used for collaboration among students, tools for exploring problems, tools for introducing problem structures, tools for developing and systematizing knowledge systems. In this study, we focused on the structure analysis of mathematical problems using Concept Map based on the analysis of previous research. In addition, we have devised a method of using concept maps for problem analysis and a method of analysis of systematic mathematical problem structure. The method developed in this study was found to have significant value by applying to the university scholastic ability test.

• Natural Product Sciences
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• v.22 no.3
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• pp.154-161
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• 2016

Phytochemical investigation on the leaves of Pileostegia viburnoides Hook.f.et Thoms led to the isolation of twenty-five compounds, and their structures were identified as n-dotriacontane (1), taraxeryl acetate (2), friedelin (3), epifriedelinol (4), canophyllal (5), stigmast-4-en-3-one (6), stigmasterol (7), (24R)-5A-stigmastane-3,6-dione (8), ursolic acid (9), pomolic acid (10), umbelliferone (11), 4-epifriedelin (12), n-octatriacontanol (13), ${\beta}$-amyrin (14), ${\alpha}$-amyrin (15), taraxerol (16), nonadecanol (17), friedelane (18), arachic acid (19), protocatechuic acid (20), n-pentatriacontanol (21), hexadecanoic acid (22), vincosamide (23), daucosterol (24), and skimming (25), respectively. To our best knowledge, compounds 1, 2, 12, 13, 17 - 19 and 21-23 were new within Saxifragaceae family. Compounds 15, 16, and 20 were produced from this genus for the first time. Compounds 4, 14 and 25 were first obtained from species P. viburnoides and compounds 3, 5 - 11, and 24 were achieved from the leaves of P. viburnoides for the first time. Furthermore, the anti-neuroinflammatory activity of these isolates was evaluated.