• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.49.2-49.2
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• 2011

$PbMoO_4$ nanoparticles were successfully obtained in the presence of ethylene glycol (EG) with the assistance of a prolonged sonication process. The nanoparticles were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), diffuse reflectance spectroscopy (DRS) and adsorption-desorption $N_2$ isotherms (BET). The catalyst prepared sonochemically showed higher photocatalytic activity than $PbMoO_4$ prepared by solid-state reaction in the degradation reactions of rhodamine B (rhB), indigo carmine (IC), orange G (OG), and methyl orange (MO) under UV-Vis light radiation. In order to elucidate aspects of the degradation mechanism of the organic dyes, some experimental variables were modified such as pH, $O_2$ level in solution, and radiation source. In general, the photocatalytic activity for the degradation of organic dyes followed the sequence IC>OG>rhB>MO.

• Journal of Chest Surgery
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• v.11 no.1
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• pp.81-84
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• 1978

A 15 years Old girl was admitted with chief complaints of intermittent claudication of lower extremity, dizziness, and headache for 5 years. On admission, malignant hypertension was noted in the upper part of body [190-150/120-110] but femoral & dorsalis pedis pulse could not palpate. Once she had experienced C. V. A. due to hypertension of upper part, about years ago. On auscultation, systolic murmur was audible along the left sternal border. E.C.G. Showed left ventricular hypertrophy pattern, and others within normal limit. Retrograde aortography demonstrated diffuse narrowing of entire thoracic aorta with underdeveloped lower abdominal aorta [below the renal artery] & both common lilac artery, and rich collaterals, but normally visualized greater arteries in the aortic arch. On left posterolasteral thoracotomy, entire descending thoracic aorta revealed marked narrowing with mild perivascular adhesion, but no mediastinal pleura adhesion. These findings suggest as congenital type of atypical coarctation in the entire thoracic aorta with mild secondary change. But histopathology was showed the findings of chronic non-specific aortitis, later. Dacron by pass graft was performed with end to side anastomosis between graft and aortic wall. After operation, all her preoperative symptoms & signs were disappeared, and discharged with good general condition.

• Journal of The Korean Astronomical Society
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• v.53 no.3
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• pp.59-67
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• 2020

We propose semi-analytic models for the electron momentum distribution in weak shocks that accounts for both in situ acceleration and re-acceleration through diffusive shock acceleration (DSA). In the former case, a small fraction of incoming electrons is assumed to be reflected at the shock ramp and pre-accelerated to the so-called injection momentum, p_inj, above which particles can diffuse across the shock transition and participate in the DSA process. This leads to the DSA power-law distribution extending from the smallest momentum of reflected electrons, p_ref, all the way to the cutoff momentum, p_eq, constrained by radiative cooling. In the latter case, fossil electrons, specified by a power-law spectrum with a cutoff, are assumed to be re-accelerated from p_ref up to p_eq via DSA. We show that, in the in situ acceleration model, the amplitude of radio synchrotron emission depends strongly on the shock Mach number, whereas it varies rather weakly in the re-acceleration model. Considering the rather turbulent nature of shocks in the intracluster medium, such extreme dependence for the in situ acceleration might not be compatible with the relatively smooth surface brightness of observed radio relics.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.356-358
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• 2002

MRI, particularly diffusion weighted imaging (DWI), plays vital roles in detection of the acute brain infarction$\^$1-4/ and others metabolic changes of biological tissues. In general, every molecule in biological tissues may diffuse and move randomly in three-dimensional space. However, in clinical diagnosis, only 2D-DWI is used. The authors have developed a new method for rapid three-dimensional DWI (3D-DWI). In this method, by refocusing of the magnetized spin with the applied gradient field, direction of which is opposite to phase encoding field. Magnetized spin of $^1$H is kept under the SSFP (steady state free precession)$\^$5-6/. Under SSFP, in addition of FID, spin echo and stimulated echo are also generated, so the acquired signal is increased. The signal intensity is increased depending on flip angle (FA) of magnetized spin. This phenomenon is confirmed by human brain and phantom studies. The performance of this method is quantitatively analyzed by using both of conventional spin echo DWI and 3D-DWI. From experimental results, three dimensional diffusion weighted images are obtained correctly for liquid phantoms (water, acetone and oil), diffusion coefficient is enhanced in each image. Therefore, this method will provide useful information for clinical diagnosis.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.28 no.8
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• pp.32-39
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• 2014

In general, non-directional LED lamps including high transmittance cover are more advantageous than directional LED lamps, which are efficient enough to improve luminous efficacy and obtain certification, allowing wide manufacture, sale, and distribution. Although KS C 7651(Self-ballasted LED lamps-Safety and performance requirements) was revised in July 2013, however, many companies are having a lot of difficulties in keeping the certification and product development for the lack of the photometric analysis for non-directional LED lamps. In this paper, through the measurement of the angular distribution of luminous flux of incandescent lamp and non-directional LED lamps, we examined the reasonability of non-directional LED lamps' standards as suggested in KS C 7651. According to the results, even if non-directional LED lamps satisfy KS C 7651, when compared to an incandescent lamp, they showed less diffusive than the incandescent lamp and the distribution of the luminous flux depending on the angle fluctuated greatly even among LED lamps. Judging by the result, the current standard of the non-directional LED lamps, KS C 7651, has been comprehended that the angular distribution of the luminous flux needs to be presented after being much more thoroughly standardized.

• Journal of Korean Traditional Oncology
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• v.10 no.1
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• pp.93-98
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• 2005

Angiocentric T-cell lymphoma is a rare form of peripheral T-cell lymphoma. The disease typically manifests clinically as an aggressive, progressively destructive disorder often with a fatal outcome. It is the aim of the present paper to derive further studies evaluating the effectiveness of Korean traditional medicine on angiocentric T-cell lymphoma with intra-abdominal metastasis. A patient with high fever, weight loss, night sweat and general weakness(B symptoms) was diagnosed as angiocentric T-cell lymphoma and chemotherapy was done more than 10 times. But the response to chemotherapy was poor, finally the lymphoma involved liver and spleen. The abdominal CT showed the hepatosplenomegaly, diffuse lymphoma of liver and spleen, massive ascites, minimal pleural effusion. Then the patient gave up the chemotherapy and only herb medications (Bohyunsoamtang-A,B) were administered. The ascites, high fever and hepatosplenomegaly gradually reduced to normal. He survived for 7 years after first diagnosis, which is much longer than average survival time in angiocentric T-cell lymphoma with B symptoms. This case may give us a possibility of that Korean traditional herb medications offer potential benefits for patients with angiocentric T-cell lymphoma, and more researches are needed.

• Journal of radiological science and technology
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• v.19 no.1
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• pp.41-49
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• 1996

We have been used super sensitive screen/film system which is thought to be the limit of sensitivity, however, we think this method is not satisfactory. As a general radiographic rule, reduction of exposure is inconsistent with improvement of image quality, but it is necessary to challenge this rule to get better method. We tried air gap method for minimal diffuse lung shadow which is difficult to find out by our routine method. As a result, air gap method with super sensitive screen/film system(SRO 1000/TMH) showed lower exposure dose, 50% of our routine system(SRO 750/SRH with grid), and better image quality for pulmonary pattern in the lower lung field.

• Journal of Chest Surgery
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• v.24 no.10
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• pp.973-978
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• 1991

From January, 1982, to December, 1990, 15 patients underwent pericardiectomy for chronic constrictive pericarditis on Department Of Thoracic and Cardiovascular Surgery, School of Medicine, Pusan National University. There were 9 male and 6 female patients [male to female ratio was 1.5: 1] ranging from 15 years to 63 years old [mean age 35.0]. All patients underwent pericardiectomy through a median sternotomy, partial cardiopulmonary bypass was performed on two patients. There were 3 postoperative death [20%]. Six cases [40%] were tuberculous origin 5 cases [34%] were Idiopathic [nonspecific chronic inflammatory change was considered to idiopathic], 2 cases [13%] were malignant origin, 2 cases [13Yo] were pyogenic origin. Dyspnea on exertion was evident in all patients and abdominal distention, general weakness, palpitation, peripheral edema were found. Eleven patients showed low voltage of QRS wave, 7 patients showed diffuse ST-T wave change, 2 patients showed atrial fibrillation on EKG. There were 6 patient showed pericardial thickening, 5 patients showed evidence of restriction, 5 patients showed pericardial effusion, 4 patients showed low cardiac output on preoperative echocardiogram. Hemodynamic response to pericardiectomy were observed; preoperative CVP 26.8 cmH2O declined to 15.0 cmH2O. Preoperative NYHA Functional class showed class II - 1, class III - 10, class IV - 4, postoperative NYHA functional class showed class I - 7, class II - 4, class Ill - l.

• Journal of The Korean Society of Clinical Toxicology
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• v.2 no.1
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• pp.23-26
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• 2004

Caustic ingestion can produce a progressive and fatal injuries to esophagus, stomach and other organs. Reported exposure to acetic acid results injuries to gastrointestinal tract, hemolysis and disseminated intravascular coagulation is general, but causing hepatic necrosis by direct injuries are rare. A 47-year-old man visited our emergency medical center complaining odynophagia and abdominal pain after ingesting glacial acetic acid ($99\%$) with suicidal ideation. At the time of arrival, the patient complained mild abdominal pain but a few hours later the patient complained severe abdominal pain with markedly elevated liver enzymes. The Abdominal Computerized Tomography showed diffuse gastric wall edema and density of wedge shaped hypodense area in right hepatic dome showing focal hepatic necrosis without significant inflammation. This seems likely to be a direct effect of the noxious agent on hepatocyte involving the portal circulation.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.4
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• pp.364-375
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• 2012

This study investigates the effects of interior design elements on the satisfaction and preference for space. Field measurements and surveys were conducted in three coffeeshops where various interior design elements were applied. Results indicate that movable tables and chairs for two people were preferred in the space. They need to be placed flexibly according to the visitors' needs to improve satisfaction for convenience. To improve spatial satisfaction, the brightness of color applied to wall surfaces was recommended to be lower than that of color used for floor surfaces. The surfaces of space and interior design elements such as furniture also need to be kept clean. Lamps with lower color temperature were effective to enhance spatial satisfaction. Light sources should be shielded when a pendant lighting system with general diffuse type was used in space. Natural daylight through window was also required for better satisfaction level. Multiple linear regression implied that the cozy feeling by electric light, existence of daylight, flexible layouts for tables and chairs, color and quality of material for tables and floor were significant contributors to overall spatial satisfaction.