• Proceedings of the KSEEG Conference
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• 2000.04b
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• pp.178-181
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• 2000

• Resources Recycling
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• v.23 no.1
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• pp.70-79
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• 2014

In this study, waste polypropylene and waste ground rubber tire(WGRT) composites were prepared by using a modular intermeshing co-rotating twin screw extruder. The effect of three main factors such as WGRT contents, particle size, compatibilizers on the properties of waste PP/WGRT composites was extensively investigated. Tensile strength of the composites was decreased with an increase in WGRT contents, whereas elongation at break and impact strength were increased. The tensile strength, elongation at break and impact strength of the composites with the smaller size of the WGRT were more enhanced. Addition of PP-g-MA into waste PP/WGRT composites exhibited better tensile strength. However, elongation at break and impact strength were slightly decreased with increasing of PP-g-MA. On the other hand, tensile strength, impact strength and elongation at break of the composites were increased by adding the EPDM-g-MA and SEBS-g-MA. Especially, elongation at break was significantly increased compared to the composite with PP-g-MA.

• Resources Recycling
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• v.3 no.2
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• pp.28-34
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• 1994

A part of used cables, such as electric and communication cables has already been recycled by using simple processing methods. However, it has been found that the main problems in recycling of the used cables are insufficient treatment of fine stranded wires and low recovery of copper by air separation process. It has been shown that copper can be effectively separated from the PE using a solvent treatment method. In the present study, the used communication wires having diameter of 0.4 mm are treated in the mixing solution of toluene and water at $86^{\circ}C$ for about 10 minutes. In the solvent treatment, the copper wires recovered have 10~15mm length, which are much longer than that of 1~2mm length copper wires recovered by air table concentration method used in current recycling plants. The process consisting of cutting, air separation and electrostatic separation would be recommendable for the treatment of mixed cables. In this investigation, fine copper powders can also efficiently be recovered from insulation materials using electrostatic separator at the conditions of 20~50RPM roller speed and 15~30KV high DC power.

• Journal of Chest Surgery
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• v.31 no.12
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• pp.1206-1211
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• 1998

Background: Pulmonary sequestration is not common and it's diagnosis needs special care such as an aortogram ar tomography. Material and Method: We have experienced 13 patients who had pulmonary sequestration from January 1990 to September 1997. Result: Six men and seven women were treated and their mean age was 25.8±14.3 years. Their chief complaints were coughing, chest pain, and no symptoms in decreasing order. There were nine intralobar(ILS) and three extralobar(ELS) pulmonary sequestrations and one patient had both. There was no preference in location of either left or right. They were mainly diagnosed by aortography and their feeding arteries commonly originated from the lower thoracic aorta. The patients with ILS were treated by lobectomy and those with ELS by sequestrectomy. Conclusion: to treat pulmonary sequestration properhy, aortogram or chest CT is warranted to iidenty the abnormal origin of feeding artery.

• Korean Chemical Engineering Research
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• v.52 no.2
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• pp.272-277
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• 2014

In this study the nanofiltration (NF) membrane treatment of a sulfuric acid waste solutions containing copper ion ($Cu^{+2}$) discharging from the etching processes of the printed circuit board (PCB) manufacturing industry has been studied for the recycling of acid etching solution. SelRO MPS-34 4040 NF membrane from Koch company was tested to obtain the basic NF data for recycling of etching solution and separation efficiency (total rejection) of copper ion. NF experiments were carried out with a cross-flow membrane filtration laboratory system. The permeate flux was decreased with the increasing copper ion concentration in sulfuric acid solution and lowering pH of acid solution, and its value was the range of $4.5{\sim}23L/m^2{\cdot}h$. Total rejection of copper ion was decreased with the increasing copper ion concentration, lowering pH of acid solution and decreasing cross-flow rate. The total rejection of copper ion was more than 70% at the experimental condition. The SelRO MPS-34 4040 NF membrane was represented the stable flux and rejection for 1 year operation.

• Progress in Medical Physics
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• v.20 no.3
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• pp.174-179
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• 2009

To track moving tumor in real time, CyberKnife system imports a technique of the synchrony respiratory tracking system. The fiducial marker which are detectable in X-ray images were demand in CyberKnife Robotic radiosurgery system. It issued as reference markers to locate and track tumor location during patient alignment and treatment delivery. Fiducial marker implantation is an invasive surgical operation that carries a relatively high risk of pneumothorax. Most recently, it was developed a direct lung tumor registration method that does not require the use of fiducials. The purpose of this study is to measure the accuracy of target applying X-sight lung tracking using the Gafchromic film in dynamic moving thorax phantom. The X-sight Lung Tracking quality assurance motion phantom simulates simple respiratory motion of a lung tumor and provides Gafchromic dosimetry film-based test capability at locations inside the phantom corresponding to a typical lung tumor. The total average error for the X-sight Lung Tracking System with a moving target was $0.85{\pm}0.22$ mm. The results were considered reliable and applicable for lung tumor treatment in CyberKnife radiosurgery system. Clinically, breathing patterns of patients may vary during radiation therapy. Therefore, additional studies with a set real patient data are necessary to evaluate the target accuracy for the X-sight Lung Tracking system.

• Journal of Yeungnam Medical Science
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• v.17 no.1
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• pp.66-74
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• 2000

Background: During the follow up period after transarterial embolization(TAE), cases of pulmonary metastasis were more prevalent in TAE-treated patients than in TAE-untreated patients. Therefore, a study was conducted to evaluate whether TAE increases the incidence of pulmonary metastasis of hepatocellular carcinoma and to clarify the risk factors for pulmonary metastasis. Methods: From March 1991 to March 1995, 156 patients who had been diagnosed with hepatocellular carcinoma by serology, and radiographic and histologic methods at Yeungnam University hospital were involved in this study. We excluded 12 patients with lung metastasis on initial diagnosis and the others. The remaining 144 patients had been followed up for at least 5 months and, divided into four groups according to lung metastasis and trans-arterial embolization treatment, and evaluated for age, sex, child-pugh score, liver cirrhosis, and level of AFP. Results: Pulmonary metastasis was found in 18.0% (26/144), of which 92.3%(24/26) and 7.7%(2/26) of the patients with and without transarterial chemoembolization, respectively. Of the patients, 23.5% (24/102) with TAE had lung metastais during follow-up periods and 4.7% (2/42) without TAE had lung metastasis. There was more likelihood for lung metastasis after TAE. but there was no difference between two groups in age, sex, child-pugh class, the presence of liver cirrhosis, and AFP. Conclusions: The incidence of pulmonary metastasis of hepatocellular carcinoma after TAE was higher. Child-pugh class was the only related clinical preciptating factors for pulmonary metastasis in TAE in our study. Our results suggest that regular chest X-ray check-ups may be more frequently needed by patients who had TAE treatment for hepatocellular carcinoma.

• Journal of Chest Surgery
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• v.39 no.11 s.268
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• pp.822-827
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• 2006

Background: Lung transplantation is a definitive therapy for a variety of end stage lung diseases. Since 1996, we have performed thirteen cases of lung transplantation including two retransplantations, and we analyzed the outcomes, complications, and survivals of these patients. Material and Method: We retrospectively analyzed the medical records of thirteen cases from July, 1996 to July, 2005. Result: During the period, 11 patients had undergone 43 lung and heart-lung transplantations, and two patients had retransplantation due to allograft failure. Mean age of recipients were $45.2{\pm}10.7$ years(range, $25{\sim}59$). Early complications were bleeding, reperfusion injury, and infection and late complications were mainly infection and post-transplantation lymphoproliferative disease. Excluding the operative mortality, the mean survival period was 16.5 months($2{\sim}60$ months). Two retransplantations had been performed 2 weeks and 13 months after single lung transplantations. Conclusion: In order to achieve long term survival, early detection of complications and proper treatment in addition to surgical skills are necessary, and these efforts can promote better lung transplantation programs in the near future.

• Applied Chemistry for Engineering
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• v.19 no.5
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• pp.568-573
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• 2008

Kinetic tests on pyrolysis of waste fishing net [WFN; nylon-6], waste ship lubricating oil [WSLO] and their mixture were carried out by thermogravimetric analysis (TGA) with heating rate of 0.5, 1.0, and $2.0^{\circ}C/min$. Pyrolysis of waste fishing net started at $300^{\circ}C$, and the main region of decomposition temperature was between 360 and $440^{\circ}C$ at each heating rate. Decomposition temperature of the mixture of WFN and WSLO was lower than that of WFN and WSLO, and the shape of thermogravimetic graph of mixture was different as well. The corresponding kinetic parameters including activation energy and pre-exponential factor were determined by differential method over the degree of conversions. The values of activation energies for the mixture of WFN and WSLO were between 98 and 427 kJ/mol as the conversion increased from 5% to 95%. Tubing reactor was used to analysis of pyrolyzed oil at $440^{\circ}C$ for 80 min. The selectivity of specific hydrocarbons was not detected and the carbon number distribution of the pyrolyzed oil was below $C_{22}$.

• Tuberculosis and Respiratory Diseases
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• v.54 no.1
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• pp.5-14
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• 2003

Background : According to the study in ICOPER (International Cooperative Pulmonary Embolism Registry), the overall mortality rate of acute pulmonary thromboembolism (APTE) at 3 months is 17.4%. According to the study for current status of APTE in Japan, the hospital mortality rate is 14%. Although the incidence and mortality rate of APTE has been increasing, patient characteristics, management strategies, and outcome of APTE in the Korean population have not yet been assessed in large series. We therefore performed the national survey for the current status of APTE in the Korean population. Methods : 808 registry patients with APTE were analyzed with respect to clinical characteristics, risk factors, diagnostic procedures, treatment, and clinical outcome. Results : Main risk factors were immobilization, recent major surgery, and cancer. Common symptoms were dyspnea and chest pain. Common signs were tachypnea and tachycardia. The majority of registry patients underwent lung perfusion scanning. Spiral CT was used in 309 patients(42.9%), and angiography in 48 patients(7.9%). Heparin was the most widely used treatment. On multivariate logistic regression analysis, onset in hospital (odds ratio 1.88, p=0.0385), lung cancer (odds ratio 9.20, p=0.0050), tachypnea (odds ratio 3.50, p=0.0001), shock (odds ratio 6.74, p=0.0001), and cyanosis (odds ratio 3.45, p=0.0153) were identified as significant prognostic factors. The overall mortality rate was 16.9% and mortality associated with APTE was 9.0%. Conclusions : The present registry demonstrated the clinical characteristics, diagnostic strategies, management and outcome of patient with APTE in Korea. The mortality rate was 9.0%, and the predictors of mortality were onset in hospital, lung cancer, tachypnea, shock, and cyanosis. These results may be important for risk stratification as well as for the identification of potential candidates for more aggressive treatment.