• Journal of Chest Surgery
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• v.43 no.5
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• pp.475-481
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• 2010

Background: We evaluated mid-term results of mitral annuloplasty using a flexible band and a completely rigid ring for mitral valve repair in patients with degenerative mitral regurgitation (MR). Material and Method: From January 2004 to September 2008, 71 patients (M:F=36:35, $55{\pm}13$ years) underwent mitral valve repair with mitral annuloplasty for degenerative MR. Ring annuloplasty was done using a Cosgrove-Edwards flexible band (Group I, n=43) or a Carpentier-Edwards classic ring (Group II, n=28). There were no differences in preoperative characteristics of the participants. Average duration of follow-up was 36 months (range: 2~69 mos). Result: There was no in-hospital mortality. Postoperative morbidity, which included atrial fibrillation (n=7) and low cardiac output syndrome (n=5) in groups I and II were similar. There was one late death in group II. The proportion exhibiting freedom from recurrent mitral regurgitation ($\geq$moderate) at 4 years in Groups I and II were, respectively, 94.5 and 91.8%, (p=0.695). Left ventricular ejection fraction decreased in the early postoperative period ($7{\pm}2$ days) and recovered by last follow-up ($25{\pm}16$ mos; p=0.002). The pattern was similar in groups I and II (p=0.905). Re-operation was performed in 3 patients (1 in Group I and 2 in Group II, p=0.316). Four-year event-free survival (free of adverse valve-related events) was 95.2% for Group I and 92.6% for Group II; this difference was not significant, p=0.646). Conclusion: The type of technique used in mitral annuloplasty to repair the mitral valve repair after degenerative MR did not affect mid-term clinical and functional results.

• Tuberculosis and Respiratory Diseases
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• v.49 no.4
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• pp.421-431
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• 2000

Background : The length of postoperative drug therapy remains controversial in pulmonary tuberculosis. We analyzed our experiences to determine the postoperative duration of chemotherapy after resection. Method : A retrospective review was performed in 66 of 95 patients that underwent pulmonary resection for pulmonary tuberculosis between January 1993 and December 1998. We compared the relapse rates according to the length of postoperative chemotherapy in each group, classified by the results of sputum AFB culture before the surgery, the number of resistant drugs, the number of prior treatment and the division of anti-TB drugs used postoperatively. Results : Fifty three of 66(80.3%) were men and 13(19.7%) were women with a median age of 33.5 years(range, 16 to 63). The mean lengths of the pre- and post-operative chemotherapies were 4.9 months, and 12.9 months respectively. Five of 66 patients (7.6%) relapsed during the mean period of follow up (39.7 months). In the group less than three times of the prior treatment, there were two relapses (20%) in Ed-the highlight above-rephrase 10 patients that were medicated for 6 months or less, and one relapse in 43 patients (2.3%) that took medicine for more than 6 months (p=0.03). In the group using second-line drugs postoperatively, there was one relapse (25%) in four patients that were medicated for 12 months or less. No patient in a total of 17 that received medicine for more than 12 months relapsed (p=0.03). Conclusion : We recommend that patients with the prior treatment less than three times should be treated for more than 6 months after resection and patients using the second-line drugs postoperatively should be medicated for more than 12 months.

• Journal of the Korean Arthroscopy Society
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• v.10 no.2
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• pp.178-183
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• 2006

Purpose: We reported the results and efficiency of arthroscopic treatment in a state of the lateral traction about the degenerative arthris of elbow Materials and Methods: Twenty one elbows with the degenerative arthritis who were followed up for at 12 months were enrolled in this study. Male were 15 cases, female were 6 cases, the mean age was 47 years and right dominant hand was 14 cases. In all cases, during arthroscopic treatment under the traction of 10 pounds, we had done synovectomy, excision of loose body and anteroposterior spur. After operation, immobilization was done in the full extension state, and then continuous passive motion (CPM) was started two day Results: The average preoperative ROM of the elbow joint was $30{\sim}l15$ degree and the average postoperative ROM of the elbow joint was $5{\sim}130$ degree. The increasement of ROM was totally 41 degree in extension 25 degree and flexion 16 degree. The decrement of VAS in pain was from 7.5 into 2.3 and the increasement of the satisfactory function was from 1.8 into 9.0. Complication was in two cases. One was paresthesia of ulnar nerve, but resolved. The other was bullae formation around the elbow joint, but cured. Conclusion: Regarding degenerative arthritis of elbow, arthroscopic treatment showed excellent result in recovery of range of motion and relief of pain. We could obtain good visual field with distraction in lateral position.

• Journal of the Korean Arthroscopy Society
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• v.16 no.2
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• pp.153-159
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• 2012

Purpose: This study aims at evaluating our results with a 5-year follow up of arthroscopic pull-out suture repair of posterior root tear of the medial meniscus. Materials and Methods: This study enrolled 30 cases who underwent a arthroscopic pull-out suture repair to treat the posterior root tear of the medial meniscus from January 2001 to May 2005 and followed up at least 5 years. The average follow-up period was 76 months (range, 60-90 months). Clinical results by use of the Lysholm knee score and radiographic grade by use of the Kellgren-Lawrence classification were evaluated and second-look arthroscopy was done in all cases. The clinical results were compared with trauma history, obesity, varus deformity and time to operation. Results: At the last follow up, the Lysholm knee score improved from 55 points to 86 points. For the radiological results, 23 cases displayed maintenance or improvement of the medial joint space on the follow up X-ray, but 7 cases displayed decrease of the medial joint space, and 1 case was lately performed total knee replacement due to progressive osteoarthritic change. Conclusion: Arthroscopic pull-out suture repair has a good result at 27 cases (90%) in minimum 5 years follow-up. The clinical improvement was significantly reduced in more severe varus angle.

• Korean Chemical Engineering Research
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• v.44 no.4
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• pp.410-416
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• 2006

For highly efficient operation of a Bunsen process section in an iodine-sulfur thermochemical hydrogen production cycle using nuclear heat, the process characteristics of $H_2SO_4-HI-H_2-O-I_2$ mixture system for separating into two liquid phases ($H_2SO_4$-rich phase and $HI_x$-rich phase) and the distribution of $H_2O$ to each phase were investigated.The experiments for process variables were carried out in the temperature range, from 298 to 353 K, and in the $H_2SO_4/HI/H_2O/I_2$ molar ratio of 1/2/14~20/0.5~8.0. As the results, for the $SO_2-I_2-H_2O$ Bunsen reaction system, the ranges between the starting point and the saturation point for two liquid phases separation were determined by calculation. The best result for the minimization of impurities (HI and $I_2$ in $H_2SO_4$ phase and $H_2SO_4$ in $HI_x$ phase) in each phase was obtained in an optimum condition with the highest temperature of 353 K and the highest $I_2$ molar composition. In this condition, the $HI/H_2SO_4$ molar ratio in the $H_2SO_4$-rich phase and the $H_2SO_4/HI_x$ molar ratio in the $HI_x$-rich phase were 0.024 and 0.028, respectively. For the distribution of $H_2O$ to each phase, it is appeared that the affinity between $HI_x$ and $H_2O$ was more superior to that between $H_2SO_4$ and $H_2O$. The affinity between $HI_x$ and $H_2O$ was decreased with increasing temperature but increased with increasing $I_2$ molar composition.

• Journal of the Korea Organic Resources Recycling Association
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• v.20 no.4
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• pp.106-117
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• 2012

Indirected heating dryer is used as one of the food waste treatment technologies for the production of the drier material supplied to the recycling facilities or end user. This study investigated the effect on drying efficiency for the operation of rotating screw with the circulating and falling movements on indirected drying process of food waste. The screw operating condition showed higher drying efficiency despite of the shorter drying time compared to the screw non-operating condition. The moisture content decreased to 14.4% from the initial moisture content of 77.1% after drying 5 hours in the screw operating condition. On the other hand, in the screw non-operating condition, the moisture content decreased slightly to 35.6% after drying 16 hours. During the drying process, variations of the water evaporation rate and particle size showed different tendencies depending on the moisture content regions. In the higher moisture content region above the glue zone(moisture content of about 50%-60%), the particle size increased and the water evaporation rate reached the highest peak. In the range of glue zone, the particle size maximized while the water evaporation rate decreased sharply. In the lower moisture content region below the glue zone, the water evaporation rate and particle size both decreased at the same time. The particle size distribution was widely ranged from 25.0mm to 0.25mm in the screw operating condition while it was narrowly distributed in the screw non-operating condition from 25.0mm to 3.56mm, especially highly concentrated to 25.0mm. It was regarded that the hygroscopic, capillary and gravitational water evaporated more easily from the intra-particle during the circulating and falling movement caused by the rotating of the screw and the difference of the cohesional force of water within intra-particle depending on the moisture content regions. Comparing the effect of the circulating and falling movement on drying efficiency, the water evaporation rates per time and per weight of dry solid in the screw operating condition were higher about 364% and 356%, respectively, than those of the screw non-operating condition.

• Journal of the Korea Organic Resources Recycling Association
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• v.24 no.3
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• pp.23-33
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• 2016

The characteristics of ammonia generated from alkaline stabilization facilities was investigated which are for organic sewage sludge from wastewater treatment plants. The highest concentration of ammonia was found in mixing and curing process in alkaline stabilization facility and ammonia mainly showed a range of 87.78 ppm($66.62mg/m^3$) to 1,933 ppm($1,467.01mg/m^3$) by detection tube. This is presumed to occur because nitrogen oxides are converted into ammonia as the sewage sludge is mixed with lime. In some facilities, hydrogen sulfide and methyl mercaptan were detected in relatively high concentrations, but odor materials except ammonia were not detected in most of the facilities. The concentration of ammonia caused by process was generally high in the order of "mixing > curing > output > storage > drying > input." It was found that odor compounds are removed by wet absorption using sulfuric acid and sodium hypochlorite in the 5 alkaline stabilization facilities currently in operation. Each facility was designed to meet the concentration of after-treatment emission in 1 ppm($0.76mg/m^3$), 50 ppm($37.95mg/m^3$) or 100 ppm($75.89mg/m^3$), but no facility satisfied the design standard for their emssion limit. In case of ammonia, some workplaces in alkaline stabilization facilities exceeded the exposure limits established by the Ministry of Labor. It appears that proper ventilation should be provided for the safety of workers in future. No odor compound including ammonia was found by detection tubes in the border of the facilities, but trace amounts of odor compounds are expected to exist, given the current operational status of facilities.

• Radiation Oncology Journal
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• v.15 no.2
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• pp.113-119
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• 1997

Purpose : Radical gastrectomy is main treatment of gastric cancer. But the result is not satisfactory with surgery alone. Most of pattern of failure remain locoregional recurrence. To improve 5 year survival postoperative chemotherapy with or without radiotherapy has been used. We analyzed patients with stage III and IV stomach cancer who had radical operation and received postoperative radiation therapy combined with or without chemotherapy retrospectively. Material and Method : From March 1985 to June 1993, 68 patients treated with curative resection and received postoperative adiuvant radiotherapy with 36Gy or more were evaluated. Median age was 60 years(range 28-66 yrs) . Patients were followed from 3 to 133 months with median follow up of 48 months. Thirty seven patients had non signet ring adenocarcinoma, 29 signet ring cell, 2 other cell. Patients with stage IIIA, IIIB, IV disease were 19, 25 and 24 respectively Chemotherapy was given to all patients except two. Results : Five-year overall survival and disease-free survival rate were 36.6% and 33.6%, respectively. Prognostic factor affecting survival were assessed. High ratio of jnvolved/dissected Iymph node, signet ring histology showed Poor Prognosis with statistical significance. Presence of residual tumor after surgery, stageIV. split course of radiation therapy, age, number of involved Iymph node, number of Iymph node dissection and grade of tumor affected survival without statistical significance, Type of chemotherapy did not affect survival. Recurrence was documented in 34 patients. High recurrence was seen in omentum and peritoneum with 23.5%, and remnant stomach, anastomosis site, A-loop and I-loop had also high recurrence with 13.2%. In field locoregional recurrence was 20.7% and total distant metastases were 39.7%. Total intraabdominal failure was 47.1% and extraabdominal failure was 13.2%. Treatment toxicity was considered to be acceptable. 22.1% of patients had grade 3 and only 1 patient had grade 4 leukopenia. Six Patients(8.8%) had weigh loss more than 10%. Conclusion : Treatment toxicity was acceptable with combined treatment with chemotherapy and radiotherapy. Locoregional recurrence was relatively low compared to distant failure with addition of irradiation. Peritoneal and omental seeding was high Five-rear surival was increased with combined modality. Radiation may eradicate minimal residual disease and improve survival, To evaluate role of radiation Prospective randomized study employing chemotherapy alone and chemotherapy plus radiation is necessary. Futhermore to reduce intraabdominal failure, role of intraabdominal chemotherapy in addition to combined chemotherapy plus radiation has to be explored.

• Journal of Chest Surgery
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• v.39 no.10 s.267
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• pp.759-764
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• 2006

Background: We analyzed post-operative angiography performed in symptomatic patients to evaluate the patency rates and the roles of grafts. Material and Method: We reviewed 52 (15%) coronary angiograms performed for recurrent angina after prior coronary artery bypass surgery from January 1995 to June 2005. A total of 345 patients underwent coronary artery bypass surgery during this period. There were 41 men and 11 women and the mean age was $64.07{\pm}15.58$ years. The median period from operation to re-angiogram was 68.5 months (range, 1 to 126 months). The numbers of grafts and peripheral anastomoses were 42 and 43 for internal thoracic artery (ITA), 14 and 20 for radial artery (RA), and 49 and 89 for saphenous vein. The mean number of anastomosis was 2.9 per patient, Result: The patency rates of ITA, RA and saphenous vein graft (SVG) were 37/43 (86%), 17/20 (85%) and 34/89 (38.2%). The patency rate of arterial grafts was significantly higher than that of SVG (p< 0.001) and the patency rate of the RA was comparable to that of ITA (p=0.942). The patency rate of sequential SVGs was higher than that of single SVG (40.3% vs 31.8%, p=0.478) and the patency rate of proximal segments in sequential anastomosis was higher than that in single anastomsis (55.6% vs 31.8%, p=0.097), but statistically not significant. Conclusion: Arterial grafts have markedly superior patency rates than SVGs, so consideration should be given to the vigorous use of arterial grafts. The patency rate of the RA was comparable to that of ITA.

• Archives of design research
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• v.16 no.1
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• pp.181-198
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• 2003

The purpose of this study is to develop a on-line design tool for effectively coping with e-Business environment, or product design process into a Cyber model for traditional manufacturers which attempts new product development under such environment. It was finally developed as a model named $\ulcorner$Design Vortal Site; e-BVDS) that was based on the structure and style of internet web site. Results of the study can be described as follows ; \circled1 e-Business is based on the Internet. All processes in the context of e-Business require models whose structure and method of use are on-line styles. \circled2 In case that a traditional manufacturing business is converted into e-Business, it is better to first consider Hybrid Model that combines resources and advantages of both such traditional and digital businesses. \circled3 The product design process appropriate for e-Business environment has to have a structure and style that ensure utilization of the process as an Internet web site, active participation by product developers and interactive communication between participants in designing and designers. \circled4 $\ulcorner$e-BDVS) makes possible the use of designers around the wend like in-house designers, overcoming lack in creativity, ideas and human resources traditional business organizations face. However, the operation of $\ulcorner$e-BDVS$\lrcorner$ requires time and budget investments in securing related elements and conditions. \circled5 Cyber designers under $\ulcorner$e-BDVS$\lrcorner$ can easily perform all design projects in cyber space. But they have some limits in playing a role as designers and they have difficulty in getting rewards if such projects completed by them are not finally accepted. \circled6 $\ulcorner$e-BDVS) ensures the rapid use of a wide range of design information and data, reception of a variety of solutions and ideas and effective design development, all of which are not possible through traditional processes. However, this process may not be suitable to be used routine process or tool. \circled7 $\ulcorner$e-BDVS$\lrcorner$ makes it possible for out-sourcing or partners businesses to overcome restrictions in time and space and improve productivity and effectiveness. But such they may have to continue off-line works that can not be treated on-line.