• Radiation Oncology Journal
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• v.13 no.1
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• pp.1-7
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• 1995

Purpose : To evaluate the efficacy of radiotherapy for the low-grade astrocy-tomas and confirm the variables influencing treatment results. Materials and Methods : Forty-six patients with low-grade astrocytoma received radiotherapy after surgical removal (36 patients) or biopsy (10 patients) from 1979 to 1990. Twenty patients had grade I histology and 26 had grade II. External radiotherapy was done by conventional schedule with the total dose of 45 to 60 Gy (median: 54 Gy). The median follow-up period was 5 years. Results : The 2- and 5-year survival rates were $80\%$ and $72\%$, respectively and the 2- and 5-year progression-free survival was $75\%$ and $63\%$, respectively. The survival was influenced significantly by the histologic grade, the histologic type, and performance status. Major complication was not found. Conclusion: In spite of good survival, the local failure was still the major problem. Age and the extent of surgery as well as three favorable factors should be considered in the future treatments.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.48 no.5
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• pp.323-334
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• 2020

Since boundary layer transition has a significant impact on the aero-thermodynamic performance of hypersonic flight vehicles, capability of accurate prediction of transition location is essential for design and performance analysis. In this study, γ-Re_θt model is improved to predict transition of hypersonic boundary layers and validated. A coefficient in the production term of the intermittency transport equation that affects the transition onset location is constructed and applied as a function of Mach number, wall temperature, and freestream stagnation temperature based on the similarity numerical solution of compressible boundary layer. To take into account a Mach number dependency of transition onset momentum thickness Reynolds number and transition length, additional correlation equations are determined as function of Mach number and applied to Re_θc and F_length correlations of the baseline model. The suggested model is implemented to a commercial CFD code in consideration of practical use. Analysis of hypersonic flat plate and circular cone boundary layers is carried out by using the model for validation purpose. An improvement of prediction capability with respect to variation of Mach number and unit Reynolds number is identified from the comparison with experimental data.

• Tuberculosis and Respiratory Diseases
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• v.51 no.3
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• pp.281-288
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• 2001

Background : The most common anterior mediastinal tumors originate from the thymus. Among them, thymic carcinomas occur as an early local invasion and wide spread metastases. However, when squamous cell carcinoma in the thymus or mediastinum is identified, an occult primary lung cancer must be excluded because the histologic types resemble those found more typically in the lung. CD5 and cytokeratin immunohistochemical staining is useful in evaluating biopsy samples from those tumors. Squamous cell carcinoma of an unknown primary origin in the mediastinum is a rare occurrence and there are only a handful of case reports. Here we describe a case with an anterior mediastinal mass of squamous cell carcinoma with unknown primary origin. A resection of the mediastinal mass without an association with the lung was performed. Immunohistochemical stallings were positive using cytokeratin 13, and negative using CD5 and cytokeratin 7. This was followed by chemotherapy for presumed thymic carcinoma.

• Korean Journal of Environmental Biology
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• v.18 no.1
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• pp.153-161
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• 2000

This study was carried out to examine the drift of Gammarus sobaegensis by acid stress as pH depression in Oweol creek from April 1996 to October 1996. The behavioral drifting was revealed to the characteristics of G. sobaegensis that is tend to increase as acid stress. And, tolerance level of G. sobaegensis to pH depression was different among the size classes. Individuals belong to small to medium size classes were weak in lower pH. Pattern of response in G. sobaegensis has a lower tolerance to acid stress at below pH 4.0 than above pH 5.0 in the artificial channel and show the possibility as an effective aquatic ecotoxicity test organism. The result of analysis of variance, water temperature (F-ratio : 66.596, p< 0.0005) and the size classes (F-ratio : 71.386, p< 0.0005) except pH level (F-ratio : 353.415, p<0.0005) were showed to the major factor for drift behavior by acid depression. [Gammarus, pH, Drift, Acid stress, Ecotoxicity test].

• Archives of design research
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• no.18
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• pp.165-174
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• 1996

In the I950s the German firm Braun began to pursue a policy of uncompromising modem design for products aimed at the upper reaches of the market. Dr. Fritz Eichler as a head of design with Hans Gugelot and Otl Aicher in the Graduate School VIm developed the guide line of Braun Design strategy as the foundation of the corporate identity programme. In 1955 Dieter Rams joined the staff, and was largely responsible for establishing the formal characteristics of Braun Design and its further development. In the mid-1950s complete product programme of the firm Braun began to be re-designed, and these undoubtedly hit the market. New design line of the firm Braun, was an exclusive avantgarde movement at that time, which became to be the epitome of the idea of an objectifiable "Good Form". By the result in the 60s and 70s, when Braun product program was completely re-designed to the new line, Braun Design had a decisive influence on the design scene of the world. Braun Design is essentially functional and concrete, which depends on perfect fulfillment of purpose, precision, safety, durability, the quality of the product and, more recently, environmental compatibility is similarly balanced and unified approach, eliminating every unnecessary detail and concentrating on ordering essential elements. elements.

• The Journal of Information Technology
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• v.7 no.2
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• pp.93-104
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• 2004

Sports scene is characterized by large amount of global motion due to pan and zoom of camera motion, and includes many small objects moving independently. Some short period of sports games is thrilling to televiewers, and important to producers. At the same time that kinds of scenes exhibit exceptionally dynamic motions and it is very difficult to analyze the motions with conventional algorithms. In this thesis, several algorithms are proposed for global motion analysis on these dynamic scenes. It is shown that proposed algorithms worked well for motion compensation and panorama synthesis. When cascading the inter frame motions, accumulated errors are unavoidable. In order to minimize these errors, interpolation method of motion vectors is introduced. Affined transform or perspective projection transform is regarded as a square matrix, which can be factorized into small amount of motion vectors. To solve factorization problem, we preposed the adaptation of Newton Raphson method into vector and matrix form, which is also computationally efficient. Combining multi frame motion estimation and the corresponding interpolation in hierarchical manner enhancement algorithm of motion parameters is proposed, which is suitable for motion compensation and panorama synthesis. The proposed algorithms are suitable for special effect rendering for broadcast system, video indexing, tracking in complex scenes, and other fields requiring global motion estimation.

• Journal of Chest Surgery
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• v.29 no.4
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• pp.420-426
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• 1996

We previously reported 344 cases of esophageal reconstruction for caustic esophageal stricture between 1959 and 1982, and this is the second report of 69 cases during 12 year period from Jan. 1983 to Feb. 1995. There were 32 males and 37 females, ranging in age from 4 to 65 years(mean 36.4 years). Caustic materials were acid in 37 (53.7%) and alkali in 31 (44.9%). All cases underwent colon interposition without esophageal resection except 3 cases of cancer complication which were resected through thoracotomy. In 64 cases isoperistaltic right colon with teminal ileum interposition were performed, and 5 cases were interposed with left colon either isoperistaltic (2 cases) or antiperistaltic (3 cases) method. Anastomotic leakage was the most frequently encountered c mplication (14.4%, 10 cases), and they were 11.6%(8 cases) from cervical, 2.8% (2 cases) from ileocolostoma. Overall operative mortality was 2.9% (2169), main causes of death were sepsis due to graft necrosis and mediastinitis. During 6 months to 12years (mean 2.Syears) follow-up of survived 67 cases, 88.1% (59 cases) ate normally, 7.5% (5 cases) complained of moderate dysphagia (eating liquid diet), and 4.5% (3 cases) were unable to eat by mouth. In our experience, reconstruction of the esphagus with the colon is a satisfactory method that can be accomplished with acceptable morbidity and mortality. The right colon is a durable and functional esophageal substitute.

• Journal of Biomedical Engineering Research
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• v.31 no.3
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• pp.217-226
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• 2010

The lower limb orthosis with a pneumatic rubber actuator, which is intended for the assistance and the enhancement of muscular activities of lower limbs was developed in this study. Compared to other knee extension assistive devices being developed by other researchers, our device is designed especially for the elderly people and intended only for slight assistance so that the subjects can keep their muscular strength. For the effectiveness of system, muscular activities of major muscles in lower limbs during sit-to-stand (STS) and squat motion were measured and analyzed. Subjects were performed the STS and squat motion with and without lower limb orthosis. We made comparison muscular activities between with and without lower limb orthosis. Lower limb orthosis was controlled using muscular stiffness force feedback that is controlled by muscular activities of the measured muscle from force sensor. For analysis of muscular activities, electromyography of the subjects was measured during STS and squat motion, and these were measured using MP 150(BIOPAC Systems, Inc.). Muscles of interest were rectus femoris(RF), vastus lateralis(VL), vastus medialis(VM) and vastus intermedius(VI) muscles in lower limbs of the right side. A biodex dynamometer was used to measure the maximal concentric isokinetic strength of the knee extensors of wearing and not wearing orthosis on right side. The test were performed using the concentric isokinetic mode of test with the velocity set at 60°/s for muscles around the knee joints. The experimental result showed that muscular activities in lower limbs wearing orthosis using muscular stiffness force of a vastus medialis muscle was reduced and knee extension torque of an knee joint wearing lower limb orthosis was increased. With this, we confirmed the effectiveness of the developed lower limb orthosis.

• The korean journal of orthodontics
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• v.37 no.5
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• pp.341-350
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• 2007

The purpose of this study was to evaluate how the friction that occurs during the sliding movement of the archwire through esthetic brackets is differently affected by bracket materials, slot designs, and tip angulations of the archwire. Methods: Eight types of brackets with 0.018 inch slots (composite: Brillant (BR); composite with metal slot: Spirit MB (SP); ceramic: Inspire (IN), Signature (SI), Cristaline V (CR); ceramic with metal slot: Clarity (CL), Luxi II (LU); and metal bracket: Integra (IT)), and placed into groups of 20 brackets in each group, were tested in artificial saliva with 0.018 inch stainless steel wire. The wire tip angulations were given as 0, 4 and 8 degrees. Results: CR group significantly showed the lowest frictional force with all wire tip angulations of 0,4, and 8 degrees. IN significantly showed the highest frictional force (p < 0.001). BR (polyoxymethylene) had significantly less frictional force than SP (polycarbonate) (p < 0.001) and showed no significant difference between metal brackets. Friction was increased as the wire tip angulations were increased, but no notches were observed on any parts of the archwire. Conclusions: According to the results of this study, esthetic brackets are superior or similar to 55 brackets from a frictional point of view.

• Tuberculosis and Respiratory Diseases
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• v.67 no.1
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• pp.37-41
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• 2009

Lymphocytic interstitial pneumonia (LIP) is a rare disorder characterized by a diffuse infiltration of the alveolar space, interstitium by lymphocytes, plasma cells, and reticuloendothelial cells. Although its etiology is unknown, LIP has been associated with autoimmune disorders and with viral infections. Because it's clinical and radiographic features are nonspecific, a confirmatory diagnosis is performed by open lung biopsy. A 59-year-old female presented dry cough, which had been present for 1 month. On initial findings of multifocal consolidation at the right middle lobe on both lower lobes in chest radiography, the first diagnosis of cryptogenic organizing pneumonia was suggested. On open lung biopsy, LIP was diagnosed. The patient had no autoimmune disease, viral infection or monoclonal gammopathy. After 3 months of corticosteroid treatment, the patient experienced improved symptoms, reduced abnormalities on chest radiography, and improved pulmonary function testing.