• Korean Journal of Environment and Ecology
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• v.23 no.4
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• pp.353-364
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• 2009

This study was conducted to evaluate the effect of erosion control works on the stream ecosystem in a mountain torrential stream. The species composition of benthic macroinvertebrates and biological water quality were investigated before and after construction of erosion control works at 5 sites. The total number of benthic macroinvertebrates before construction was 3,086 individuals including 4 phyla, 6 classes, 11 orders, 22 families, and 25 species, but after construction it has decreased to 1,208 individuals including 4 phyla, 6 classes, 10 orders, 17 families, and 19 species. Especially, the diversity, richness, and evenness indices, which were calculated based on existing number of biological species, have decreased or not produced at the erosion control sites, where biological species were not found or the minimum number of species were found. The results of community analysis of benthic macroinvertebrates and ESB(Ecological Score of Benthic macroinvertebrate community) indicated that the environmental qualities of the stream based on saprobity, environmental condition, and water quality decreased after the construction at all sites: before construction, the top of the stream was satisfactory and some satisfactory, the middle was some defectiveness, and the lower was defectiveness and very defectiveness; after construction, all parts of the stream except some parts of the top were very defectiveness. Moreover, the water quality of torrential stream was rated between I to III before construction, but after construction, it declined to $IV{\sim}V$ except control. The habitat damage of benthic macro invertebrates occurred at all investigation sites after the construction of erosion control works led to reduction of the number of biological species and water quality deterioration. The results reported in this study were collected directly after the construction of erosion control works. Therefore, additional studies are needed to further explore the effect of disaster-prevention of erosion control works and the recovery process of stream ecosystem through long term monitoring.

• Clean Technology
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• v.20 no.2
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• pp.189-201
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• 2014

Partial oxidation, $CO_2$ reforming and the oxidative $CO_2$ reforming of $CH_4$ to produce synthesis gas over supported Ni hydrotalcite-type ($Ni_{0.5}Ca_{2.5}Al$ catalyst) catalysts were carried out and the effects of metal supports (i.e.; Mg and Ca) on the formation of a stable double-layer structure on the catalysts were evaluated. The $CH_4$ reforming stability was determined to be affected by the differences in the interaction strength between the active Ni ions and support metal ions. Only a Ni-Mg-Al composition produced a highly stable hydrotalcite-type double-layered structure; while the Ni-Ca-Al-type composition did not. Such structure provides excellent stability for the catalyst (-80% efficiency) as confirmed by the long-term $CO_2$ reforming test (-100 h), while the Ni-Ca-Al catalyst exhibited deactivation phases starting at the beginning of the reaction. The interaction strength between the active metal (Ni) and the supporting components (Mg and Al) was determined by temperature-programed reduction (TPR) analyses. The affinity was also confirmed by the TPR temperature because the Ni-Mg-Al catalyst required a higher temperature to reduce the Ni relative to the Ni-Ca-Al catalyst. The highest initial activity for synthesis gas production was observed for the $Ni_{0.5}Ca_{2.5}Al$ catalyst; however, this activity decreased quickly due to coke formation. The $Ni_{0.5}Ca_{2.5}Al$ catalyst exhibited a high reactivity and was more stable than the other catalysts because it had a higher resistance to coke formation.

• Management & Information Systems Review
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• v.31 no.4
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• pp.559-592
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• 2012

In spite of the transitional changes in the shoe industry in Busan area, regular academic studies on the management plan to improve the practical competitiveness of footwear industry focused in the materials, bio-dynamics, components, and designs, etc. in the engineering viewpoint are very rare. Many reports of policies were published from late 190's to 2000's but they were limited to the identification of practical situations and the measures for strategic alternatives and were not developed to be the academic studies to improve the competitiveness in terms of management control. It is intended to seek for the measures to be reviewed as the alternatives to improve the self-competitiveness of footwear companies by approaching the problems limited to such specific area in the viewpoint of management control. The core of this study is to provide the alternative plans for expansion of the industrial foundation by seeking for the measures to improve competitiveness with application of knowledge management as an alternative for improvement of not transient but sustainable industrial competitiveness, in order to help the export of shoes from Busan area which has been rapidly increased since the Korea-USA FTA and Korea-EU FTA. In such viewpoint, in the study, a questionnaire survey was performed related with the issues of Busan's footwear industry and the plan to implement knowledge management was discussed for improvement of the competitiveness of footwear industry based on the result of such questionnaire survey. As most of studies and directions have been focused in functional shoes, designs, materials, and components, etc., which are related with the properties of human dynamics, as the alternatives for improvement of the footwear industry of Busan area and did not suggest the measures to make basic changes in the management of companies, the implementation of knowledge management was emphasized in order to seek for the direction of such plan. The purpose of this study is to suggest an alternative for construction of industrial eco-system for high added value by seeking for the probability of knowledge management for conversion of footwear industry into knowledge industry. In order to accomplish the effect of increased export as the result of FTA, current management method of footwear companies is limited and the effect of FTA should be maximized by improving the competitiveness with implementation of knowledge management methods. Settlement of such knowledge management will act as the momentum to improve the competitiveness of footwear companies and, in a long-term viewpoint, will be able to maximize the improvement of knowledge industry and creation of job opportunities.

• Tuberculosis and Respiratory Diseases
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• v.40 no.6
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• pp.638-645
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• 1993

Objectives: The functional effects of pulmonary resection are dependent on the preexisting function of resected and remaining tissue as well as on the compensatory potential of the remaining tissue. Nowadays, large pulmonary resections are usually applied to lung cancer patients often already compromised by chronic lung disease. It is important to evaluate the pulmonary reserve after lung resection preoperatively in the decision of operability and extent of resection. The aim of this study was to evaluate the changes of pulmonary function after pulmonary resection. Methods: 8 lobectomized and 8 pneumonectomized patients were evaluated. The pulmonary function test was performed preoperatively and in immediate postoperative period and thereafter to 5 years at 3 months interval. Results: 1) The pulmonary function 1 week after operation was significantly low compared with predicted values in, lobectomy and pneumonectomy groups(p<0.05), and improved closely to their predicted values 3 months after operation. 2) The FVC was maintained above predicted value at 6-24 months and similar to predicted value thereafter in lobectomy group. In pneumonectomy group, the FVC maintained similar to predicted value at 6-36 months and improved above its predicted value thereafter. 3) The FEV1 was maintained similar to their predicted values from 6 months to 5 years after operation in both groups. 4) The FEV1/FVC did not change in the course of time in both groups. 5) The FEF25-75% was maintained similar to predicted value at 6-60 months after operation in lobectomy group, but it decreased under predicted value after 1 year in pneumonectomy group. 6) The MVV was maintained similar to predicted value at 6-24 months and decrease thereafter in lobectomy group. In pneumonectomy group, the MVV was maintained at 6-60 months after operation. 7) The differeces in the pulmonary function(FVC, FEV1, FEF25-75%, MVV) between two groups were seen only at 6 months after operation(p<0.05). Conclusion: The pulmonary function was markedly decreased immediately after operation, improved similar to predicted value at 1-3 months, highest at 6 months, and maintained similar to the predicted value to 5 years after pulmonary resection. The difference in the pulmonary function between two groups was the most at 6 months after operation.

• Tuberculosis and Respiratory Diseases
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• v.42 no.4
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• pp.474-480
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• 1995

Background: In spite of initial intensive and long-term chemotherapy for pulmonary tuberculosis, many problems remain in the treatment of the residual lesion. The role of surgical intervention for pulmonary tuberculosis is getting rid of such residual lesion of pulmonary tuberculosis to support the healing process and to induce bacteriologically negative conversion in the end. Method: We experienced 30 cases of pulmonary resection for pulmonary tuberculosis from Aug. 1994 through Apr. 1995 in National Masan Tuberculosis Hospital. We conducted retrospective study to analyze several variables for the cases. Results: 1) The ratio between male and female was 4:1(male 24, female 6) and the age of peak incidence was in 3rd and 4th decades. 2) Indications for pulmonary resection in the radiographic findings were cavitary lesions of 19 cases(63.3%), destroyed one side of 8 cases(26.7%) and destroyed one lobe of 3 cases(10%). 3) 16 of 20 cases with unilateral lesions and all of 10 cases with bilateral lesions on chest X-ray films showed AFB positive on preoperative sputum smears. 14 cases(87.5%) of unilateral lesions and 9 cases(90%) of bilateral ones were converted into AFB negative postoperatively. Negative conversion rates of pneumonectomy and lobectomy cases were 100% and 85.7%, respectively. 4) Preoperative combined disease was 3 cases(10%) of DM and postoperative complications were 2 cases(6.7%) of dead space and no death. Conclusion: Chemotherapy only has some limitation in treatment of all tuberculosis. So, surgical intervention for pulmonary tuberculosis is an effective method as partner of chemotherapy.

• Tuberculosis and Respiratory Diseases
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• v.44 no.6
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• pp.1225-1233
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• 1997

Background : Cervical tuberculous lymphadenitis(CTL) is one of the most common extra-pulmonary tuberculosis. Recently overall incidence of pulmonary tuberculosis has decreased, but the incidence of tuberculous lymphadenitis has not decreased. Its duration of treatment is still controversial and the pathogenesis, prognosis and relationship with other site tuberculous are poorly published. So we did a retrograde study of 120 cases of confirmed CTL about its clinical manifestations. Method : All patients were applied fine needle aspiration(FNA) of palpable enlarged cervical lymph nodes and 114 patients were examined for AFB smear and 34 patients for TB culture with aspirated fluid. 57 patients were examined Mantoux test(5TU with PPD-S). With above methods, a total of 120 patients was diagnosed as having CTL. Results : 1) CTL is most prevalent in young women between the age of 20~30 years and the incidence of CTL in female is 2.5 times higher than that of male. It is located most commonly in the posterior cervical area. The most common presenting symptom is painless palpable enlarged cervical lymph nodes. 2) With FNA of enlarged cervical lymph nodes, the percentage of histopathological positivity is 82.3%. The percentage of AFB smear positivity is 38.6%, and that of TB culture positivity is 17.6%(p<0.001). 3) Pulmonary tuberculosis is noted in 79 cases(65.8%). And 42 cases(53.5%) of them had minimal pulmonary tuberculosis. In 14 cases(11.7%), other extrapulmonary tuberculosis coexsisted and pleural tuberculosis was most Common in the order. 4) CTL was treated with anti-tuberculous medication(first line drug) and median treatment duration was 18.5months. During treatment, the size of involved lymph nodes decreased gradually in 62 cases(75.8%), newly developed lymph nodes were found in 25 cases(30.4%), fluctuation formation in 22 cases(26.8%) and fistula formation in 14 cases(17.0%). Conclusion : CTL is prevalent in women between the age of 20~40 years and it involves posterior cervical area most commonly. CTL is treated with long-term anti-tuberculous chemotherapy. We think it is one manifestation of systemic disease and frequently coexisting with pulmonary tuberculosis. Despite anti-tuberculous chemotherapy, the size of involved lymph nodes was increased, new lymph nodes were developed or fluctuation and fistula formed in involved lymph nodes. After sufficient medication, when the patient felt pressure discomfort from enlarged lymph node or fistula was formed, we recommended total excision of involved lymph nodes.

• Tuberculosis and Respiratory Diseases
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• v.44 no.3
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• pp.629-638
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• 1997

Background : Surgical intervention is known as the principle management for hemoptysis of significant amount. But surgical procedure is applicable to only small number of patients because of increased mortality in emergency surgery and various functional and structural problems after lung resection. Bronchial artery embolization(BAE) has been used as an alternative interventional technique for immediate control of patients with increased risk for surgery due to recurrent or massive hemoptysis. BAE also has limitations such as recurrent bleeding after procedure and its role for the application to small amount of hemoptysis is still not established. Method : To evaluate immediate and long term effectiveness of BAE, we analysed 65 patients with hemoptysis according to therapeutic modalities they received ; BAE versus conservative management. Results : The success rate for immediate control of hemoptysis was significantly higher in BAE group with 43 cases(100%) among 43 cases compared with 17 cases(77%) among 22 cases in conservative group (p < 0.001). The disease control duration was $19.5{\pm}8.06$ months in BAE group and $18.8{\pm}6.06$ months in conservative group(p > 0.05). The therapeutic response in BAE group was 82%(36/43 cases) and 95%(21/22 cases) in conservative group (p > 0.05). According to the amount of hemoptysis, the therapeutic response were seen in 91%(29/32 cases) in less than 100ml and 85%(28/33 cases) in 100~400ml (p > 0.05). According to the manifestation of hemoptysis, the therapeutic response in groups of recurrent and nonrecurent were 87%(20/23 cases) and 88%(37/42 cases)(p > 0.05). Conclusion : The difference of therapeutic response between BAE and conservative group in patients with small amounts of hemoptysis was not found except for immediate control of hemoptysis.

• Tuberculosis and Respiratory Diseases
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• v.52 no.1
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• pp.46-53
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• 2002

Background: Pulmonary aspergilloma is relatively common in korea. It arises from the colonization and proliferation of Aspergillus in preexisting lung parenchymal cavities, in particular tuberculosis. The most common symptom in this disorder is hemoptysis, which mayor may not be massive and life threatening. A routine chest radiography and computed tomography (CT) are the most important diagnostic procedures. A surgical resection of the aspergilloma has recently been recommended, because of the relatively low incidence of postoperative complications than in the past. A more concentrated sample of patients with aspergilloma, who either underwent a thoracotomy or tested positive for aspergillus antibodies, were reviewed. Method : The medical records of twenty-two patients with aspergilloma, who had a proven thoracotomy (9 cases), or who tested positive for the diagnostic procedure and/or aspergillus antibodies (13 cases) from January 1995 to December 2000, were reviewed retrospectively. Results : The most common underlying lung disease was a current or old healed tuberculosis, and 3 patients had cultures of mycobacterium other than tuberculosis (MOTT). The mean time until the aspergilloma was detected 5.91 years in the healed tuberculosis cases. The others cases involved a lung abscess, bronchiectasis and without lung disease. The extrapulmonary disease was alcoholism and diabetes. Hemoptysis was most common in 72.7%. A computed tomography (CT) is useful for diagnosis. The right upper lobe, especially the posterior segment, is the most common location. Bronchial artery embolization is ineffective for a long term follow-up. A lobectomy is most common in a thoracotomy, and intra-operative and post-operative complications are rare. During follow-up, the mortality rate, not from the aspergilloma but from respiratory failure, was 13.6%. Conclusion : Aspergilloma is a common cavitary lung disease, It mainly arises from tuberculosis, either current or healed, but extra-pulmonary disease including alcoholism or diabetes are other possible risk factors. Their most common problem in aspergilloma is hemoptysis. Surgery has a low risk of post-operative complications and is recommended in relatively preserved lung function or healthy patients. Medical maneuvers including embolization, and the local insertion of certain materials needs to be studied more closely.

• The Journal of Korean Academy of Prosthodontics
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• v.48 no.1
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• pp.28-40
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• 2010

Purpose: The aim of this retrospective study was to provide long-term data about the correlation between multifactorial local factors and the survival of implants. Material and methods: During 19 years (1991 to 2009), 2796 implants were placed in 879 patients. From dental charts and radiographs, the following data were collected: patient's age at implant placement, gender, implant system, surface, length, diameter, location of implant placement, bone quality, primary stability, type of prosthesis. The correlations between these data and implant survival were analyzed. Statistical analysis was performed using Kaplan-Meier survival analysis, Chi-square test, odds ratio. Results: 1. Among the 2796 implants, 150 implants failed that resulted in a cumulative survival rate of 94.64%. The cumulative survival rate of smooth surface implants (91.76%) was lower than rough surface implants (96.02%). 2. Anatomic location, implant surface, diameter of smooth surface implant, primary stability, type of prosthesis, patient's age and gender were significantly associated with implant survival (P < .05). 3. No significant difference in implant survival was found in relation to the following factors: implant length, bone quality, diameter of rough surface implants and type of rough surface according to implant manufacturer (P < .05). Conclusions: Local factors such as anatomic location, implant surface, diameter of smooth surface implant, primary stability and type of prosthesis have a significant effect on implant survival.

• The Journal of Korean Academy of Prosthodontics
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• v.47 no.2
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• pp.215-221
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• 2009

Statement of problem: Recently the populations of patients receiving implant surgery are greatly increase for maintaining oral health. Purpose: This study was conducted for implanted patients to assess the chewing ability patient satisfaction level and changes in quality of life before and after the implant surgery. Material and methods: The current study subjected 109 adult patients, older than 20 years of age, who received implant surgery from December, 2006 to October, 2007 at the 6 dental clinics located at Daegu and Ulsan metropolitan cities. Twice of surveys were conducted for the patients before and after receiving the dental implant surgery. Results: As the motivation of receiving implant surgery, 45.9% of the patients selected the surgery for the chance o "f chewing function recovery", and " failure of treatment and complications" was found to be the most worrisome at the time of surgery by recording 38.5%.The satisfaction level before the implant surgery scored 30.37, while the score was increased to 45.01 after the surgery by showing a significant difference before and after receiving the surgery(P<.001). Regard on the surgery, 91.8% of the patients responded as "Satisfy", and 89% of the study subjects responded that they have willingness to recommend the surgery to their families and friends. The chewing ability score measured by using the surveys on edible foods, the score before the surgery was 15.24, while the score was increased to 19.11 after the surgery by showing a significant difference before and after receiving the surgery(P<.001). The quality of life score was also found to be increased to 11.17 after the surgery from 9.99 before the surgery by showing a significant difference(P<.001). Conclusion: In a future, the studies on the numbers of implanted loss teeth and the location of tooth loss are necessary, more long-term follow study are needed, and it is thought to be necessary to enlarge the sample size of subjects in conducting the studies.