• Journal of Korean Society for Atmospheric Environment
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• v.17 no.2
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• pp.133-145
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• 2001

The receptor modeling is one of the statistical methods to achieve reasonable air pollution strategies. The pur-pose of this study was to survey the concentration variability oi inorganic elements and ionic species in the PM-10 particles, to qualitatively characterize emission sources by an advanced algorithm called positive matrix factoriza-tion(PMF) as a receptor model that can strictly provide results in every loading matrix. A total of 254 samples was collected by a PM-10 high volume air sampler from Mar. 1997 to Feb. 1998 in Kyung Hee University at Suwon Campus. Fourteen chemical species(Zn, Cu, Fe, Pb, Al, Mn, $Na^{+}$, NH$_4$+, $K^{+}$, $Mg^{2+}$, $Ca^{2+}$, $SO_4^{2-}$, $NO_{3}^{-}$, and $Cl^{-}$) were determined by AAS and IC methods. The study results showed that the average monthly concentration of PM-10 particles were 86.3$\mu\textrm{g}$/$\textrm{m}^3$ in March (maximum) and 28.5$\mu\textrm{g}$/$\textrm{m}^3$ in August(minimum), respectively. The concentrations of Na+, NH$_4$+, $K^{+}$ and $Cl^{-}$ in winter, $Mg^{2+}$, $Ca^{2+}$ and $NO_{3}^{-}$, in spring, and $SO_4^{2-}$ in summer showed the largest peak concentration for the respective season. Through and app-lication of a PMF program of Pm-10 concentration data of Suwon, 9 sources were qualitatively identified , such as incineration source, oil burning source, soil related source, open burning source automobile source, coal burning sources, secondary sulfate related source, and secondary nitrate related source.

• Journal of Yeungnam Medical Science
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• v.9 no.2
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• pp.321-326
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• 1992

The study consisted of all patients over 35years old undergoing surgical repair of atrial septal defect for the period from June 1985, to August 1992. The following results were observed. 1. ASD was closed with patch in 11(73%) patients. 2. The relationship of pulmonary artery systolic pressure to Qp/Qs ratio was not significant. 3. Before operation 6 patients were in NYHA functional class II, 8 were in class III, After operation 8 patients were in class I, 6 were in class II. 4. Atrial fibrillation has persisted in 3 patients and returned regular rhythm in 1 patient after surgery. 5. There was no operative mortality and we had good surgical results regardless of patient's age.

• Journal of Korean Society for Atmospheric Environment
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• v.27 no.5
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• pp.545-557
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• 2011

The objective of this study was to estimate the trends of each pollutant using the air pollution monitoring networks data from January 2005 to December 2008 in Daegu area. Also, the spatial characteristics of each pollutant were determined using the Pearson correlation coefficients and COD (coefficients of divergence). In this study, the trends of hourly, monthly, seasonal, and total average concentrations of each pollutant for the 10 sites were analyzed. The Ihyeon site showed highest concentration for the $SO_2$, $NO_2$, and PM10}. In the case of $O_3$, the Jisan site showed highest concentration among the other sites. Also, industrial area presented highest concentration for the $SO_2$, CO, and PM10. On the other hand, $NO_2$ showed highest in commercial area. The IDW (inverse distance weighting) method was used to estimate characteristics of spatial distribution. The results provide identify spatial distribution for each pollutant. Also, the Pearson correlation coefficients and COD values provide spatial variability among the monitoring sites. The COD of each pollutant showed very low values for all of the sites pairs. On the other hand, the Pearson correlation coefficients showed high values for all of the sites pairs. Finally, analysis of spatial variability can be used to characterize the spatial uniformity and similarity of concentrations from each pollutant.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.2
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• pp.207-211
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• 2007

It is a quite quality concerning to control the temperature of single crystalline growth as it does when we get most of heat treating products. It is also important factor to control the temperature when we make the $Al_2O_3$(single crystalline) used to artificial jewels, glass of watches, and heat resistant transparent glasses. Thus, it is a major interest to get the proper temperature in accordance with the time process while we are making mixture of oxygen and hydrogen to have the right temperature. In this paper, we will study of electrical valve positioning system with DC-Motor for the gas mixture to improve the quality of products.

• Resources Recycling
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• v.23 no.2
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• pp.90-97
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• 2014

The artificial dry silica used as dry aggregates in domestic is collected increasing every year. It is required drying process for the production of dry aggregates, therefore, it is main culprit of the cost up of aggregates and air pollution by using fossil fuel for the solution, it is developed alternative aggregates for the replacement of dry aggregates very ungently. In this article, the patents and papers for the recycling technology on the high-efficiency rapid cooling method of ladle furnace slag were collected and analyzed. The open patents of USA (US), European Union (EP), Japan (JP), and Korea (KR) and SCI journals from 1977 to 2013 were investigated. The patents and journals were collected using key-words and filtered by the definition of the technology. The patents and journals were analyzed by the years, countries, companies, and technologies and the technical trends were discussed in this paper.

• Journal of Chest Surgery
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• v.31 no.12
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• pp.1234-1237
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• 1998

Patients with aortic root disease, frequently seen in Marfan syndrome have progressive dilatation of the aortic sinuses and dilatation and distortion of the aortic annulus, leading to aortic incompetence. They are currently treated with composite graft replacement of the ascending aorta and aortic valve and reimplantation of the coronary arteries. Recently, we experienced an aortic root replacement with aortic valve preservation in a patient with annuloaortic ectasia. The ascending aorta and sinus was excised except the aortic annulus and aortic valve. The aortic valve was reimplanted inside of a collagen-impregnated tubular Dacron graft. The coronary arteries were also reimplanted. The patient was followed up for six months and reevaluated with the echocardiography. Postoperative Doppler echocardiography revealed normal aortic valve function. With this technique, it is possible to preserve the native aortic valve if the aortic leaflets are anatomically normal.

• Journal of Chest Surgery
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• v.30 no.7
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• pp.724-728
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• 1997

We experienced a case of thoracic aortic aneurysm combined with coronary artery disease. A 68-year-old man complained of anginal pain in the left anterior chest and nonspecific pain in the posterior chest. The aneurysm was extending from left subclavian artery to the diaphragm and sign of impending rupture was noted in the chest CT. Coronary angiograms r vealed significant obstruction of left circumflex coronary artery(>95%) and left anterior descending artery(>50%). Exposure was obtained through the left posterolateral thoracotomy incision in the 4th intercostal space and then partial femoro-femoral cardiopulmonary bypass was established. After aortic cross clamping, the aneurysmal sac was opened and repaired with interposition of 26 mm Hemashield graft. Under the beating heart with femoro-femoral cardiopulmonary bypass, aorto-left circumflex coronary bypass with autogenous saphenous vein used as conduit was performed. Postoperatively multiple cerebral infarction ensued due to intraoperative hypovolemic shock and hypoxic brain damage during cardiopulmonary bypass. Currently, the patient's mental status is drowsy and in an improving state.

• Journal of Chest Surgery
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• v.43 no.4
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• pp.458-461
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• 2010

A 53-year-old woman had right aortic arch, Kommerell’s diverticulum and aberrant left subclavian artery (LSA) without any compressive symptoms. Hybrid operation was performed. This consisted of LSA bypass using a 6 mm ringed Gore-Tex graft between the left common carotid artery and aberrant LSA via a left supraclavicular incision, and stent graft insertion into the aortic arch via the right femoral artery. Postoperative computed tomography as well as intraoperative angiography demonstrated successful occlusion of Kommerell’s diverticulum and bypass of the aberrant LSA. There were no complications related to the operation or the intervention.

• Journal of Chest Surgery
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• v.35 no.9
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• pp.688-691
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• 2002

Takayasu's arteritis is a chronic inflammatory disease of unknown cause. It predominantly affects the aortic arch and its branches. Concomitant involvement of coronary and renal arteries is a rare entity. In this report, we described successful treatment of a patient with Takayasu's arteritis associated with coronary and renal arteries stenosis. A 23-year-old woman was presented with chest pain on exertion. Angiographic studies demonstrated left main coronary, bilateral renal, and left subclavian arteries stenosis. She underwent angioplasty and stenting of bilateral renal artery. After one week, coronary artery bypass grafting using greater saphenous veins and aorto-subclavian bypass with PTFE vascular graft were done simultaneously. She was discharged on the 13th postoperative day without any complications.

• Journal of the Korea Convergence Society
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• v.8 no.11
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• pp.439-445
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• 2017

This study compares the safety of nail products by reviewing domestic and foreign literature for preparing a safety management plan for reduction of human body exposure to hazardous substances that occur in nail products. We analyzed the cases of exceeding the limit value of hazardous substances. In domestic artificial nail adhesive and nail tip, toluene content was 40.3 times higher than the standard value, chloroform was 22.8 times, and antimony was 15.4 times. In developed countries, it is obligatory to provide material safety data and workplace ventilation equipment through various policy researches. However, there is no safety standard in Korea. Therefore, if the regulations for safety management should be established with each characteristic of nail product, work environment, workers, and consumers, and the awareness of hazardous substance cosmetics should be improved through development and dissemination of various educational programs, it can contribute to disease prevention and health promotion.