• Korean Journal of Cleft Lip And Palate
• /
• v.3 no.1
• /
• pp.23-31
• /
• 2000

Objective: When an alveolar cleft is too large to close with adjacent mucobuccal flaps or large secondary fistula following a primary bilateral palatoplasty exists, a one-stage procedure for bone grafting becomes challenging. In such a case, we used the tongue flap to repair the fistula and cleft alveolus in the first stage, and bone grafting to the cleft defect was performed in the second stage several months later. The purpose of this paper is to report our experiences with the use of an anteriorly-based Y-shaped tongue flap to fit the palatal and labial alveolar defects and the ultimate result of the bone graft. Patients: A series of 14 patients underwent surgery of this type from January 1994 to December 1998.The average age of the patients was 15.8 years old (range: 5 to 28 years old). The mean period of follow-up following the 2nd stage bone raft operation was 45.9 months (range: 9 to 68 months). In nine of the 14 cases, the long-fork type of a Yshaped tongue flap was used for extended coverage of the labial side alveolar defects with the palatal fistula in the remaining cases the short-forked design was used. Results: All cases demonstrated a good clinical result after the initial repair of cleft alveolus and palatal fistula. There was no fistula recurrence, although Partial necrosis of distal margin in long-forked tongue flap was occurred in one case. Furthermore, the bone graft, which was performed an average of 8 months after the tongue flap repair, was always successful. Occasionally, the transferred tongue tissue was bulging and interfering with the hygienic care of nearby teeth; however, these problems were able to be solved with proper contour-pasty performed afterwards. No donor site complications such as sensory disturbance, change in taste, limitations in tongue movement, normal speech impairments or tongue disfigurement were encountered. Conclusion: This two-stage reconstruction of a bilateral cleft alveolus using a Y-shaped tongue flap and iliac bone graft was very successful. It may be indicated for a bilateral cleft alveolus patient where the direct closure of the cleft defect with adjacent tissue or the buccal flap is not easy due to scarred fibrotic mucosa and/or accompanied residual palatal fistula.

• Journal of Korean Society of Forest Science
• /
• v.102 no.3
• /
• pp.390-397
• /
• 2013

The study, utilizing a data envelopment analysis (DEA) which is one of the nonparametric estimation methods, aims to evaluate the management efficiency of chestnut tree cultivators in such provinces in Chungchungnam-do as Cheong-yang, Gong-ju, Bu-yeo and so on. The analysis data of this study is based on inputs and outputs of 20 forestry households surveyed in the 2012 survey titled 'A Study on Current Level and Condition of Chestnut Cultivation and Management', which was conducted from March 2012 to October 2012. The elements of inputs are composed of management cost, harvesting cost, material cost, non-operation expenses and cultivation area, while the element of output is a gross margin only. Then the study analyzes a technical efficiency, a puretechnical efficiency and a scale efficiency using CCR and BCC model among DEA methods. Based on that, it also provides improvement methods for forestry households that turned out to be inefficient. In order to verify the result of DEA analysis, the study additionally compares a result of this efficiency study with that of chestnuts management standard diagnostic table. According to the result, the average value of technical efficiency analyzed was 0.667, proving to be inefficient in general. Given that the average value of pure-technical efficiency was 0.944 and that of scale efficiency was 0.703, it can be inferred that inefficiency exists in the field of scale, not in the field of cultivation techniques. As for forestry households with the efficiency score of 1, it is shown that there were 6 households that recorded 1 in the technical efficiency field and 13 households that recorded 1 in the pure technical efficiency. Meanwhile, there were 6 households that recorded 1 in all of the three aspects. In the comparison with the scores from chestnuts management standard diagnostic table, there were 5 households made a high score of over 80, among which are 3 households with score 1 in the technical efficiency. Also, the results of this study and the chestnuts management standard diagnostic table are proved to have the same result, both of them showing the same households that recorded the highest score and the lowest score. This means the management efficiency evaluation using DEA can be applied to the fieldwork along with the chestnuts management standard diagnostic table.

• Journal of Gastric Cancer
• /
• v.8 no.2
• /
• pp.97-103
• /
• 2008

Purpose: Radical surgery is the standard therapy for patients with resectable cardia cancer. In the case of type II disease with esophageal invasion, a transhiatal extended radical total gastrectomy is needed or a gastroesophagectomy through an abdomino-thoracotomy, depending on the extent of the esophageal invasion. We analyzed the indications and outcome of left colon interposition as an esophageal substitution. Materials and Methods: Between 1 January 1994 and 31 December 2006, 10 patients underwent left colon interposition after gastroesophagectomy through an abdomino-thoracotomy or the tanshiatal approach for type II cardia cancer at the Department of surgery, Yonsei University College of Medicine. The outcomes of these patients were reviewed and compared, with those who underwent a Roux-en-Y, by gender and age matched analysis, retrospectively. Results: There were nine males and one female with a mean age of 52.5 (range, 16~72). The operation time was $449.00{\pm}87.39minutes$. The mean distance between the proximal resection margin and the cancer was $6.56{\pm}3.65cm$; the maximum size of the tumor was $9.90{\pm}3.97cm$. These measures differed significantly from patients who underwent Roux-en-Y. The patients had a double primary cancer in the cardia and esophagus. There were no events of colon necrosis. However, a pneumothorax occurred in one patient (10%) and a proximal anastomotic stricture occurred in one patient. There were no reports of heartburn, regurgitation, thoracic or epigastric fullness, and one patient even gained weight, 16 kg. Conclusion: Colon interposition after esophagogastrectomy was safe and effective and should be considered as an additional surgical option for locally advanced type II cardia cancer patients with esophageal invasion.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.22 no.2
• /
• pp.206-216
• /
• 2000

Predictional study for lateral change between pre- and post-orthognathic surgery has been emphasized mainly on anterior area of lateral profile; upper lip, lower lip and chin et al. So interest for lateral profile change has been less in posterior area of lateral profile and literature analyzing gonial angle change is rare. The purpose of this study is to make prediction for gonial angle change possible and to offer somewhat treatment guidance for gonial angle to be improved by investigating overall gonial angle change between pre- and post-orthognathic surgery and inquiring into factors influencing on pattern of genial angle change. For this study 35 patients were selected retrospectively. Lateral cephalometric radiographs were taken in just pre-op time, pod 1 day, pod 1 year. They were analyzed and genial angles were measured. The results were as follows : 1. Gonial angle at pod 1 day was decreased about $9.3^{\circ}$ than pre-op and gonial angle at pod 1 year was increased about $4.0^{\circ}$ than pod 1 day. So genial angle at pod 1 year was decreased about $5.3^{\circ}$ than pre-op genial angle(p<0.01). 2. Mean pre-op gonial angle was $129.4^{\circ}$, showing significantly high value than normal and mean gonial angle at pod 1 year was $124.1^{\circ}$, showing value near to normal. 3. Mean gonial angle change between pre-op and pod 1 year was decreased about $5.4^{\circ}$ in female and $5.3^{\circ}$ in male. There was no statistically significant difference between male and female(p>0.05). 4. Principal factor influencing on decreased gonial angle in gonial angle change between pre-op and pod 1 year was amount of mandibular setback. 5. Principal factor influencing on increased gonial angle in gonial angle change between pod 1 day and pod 1 year was % horizontal relapse, and it was thought that resorption and bone remodelling on posterior area in mandibular distal segment also were related to increased gonial angle. 6. It is thought that sagittal split ramus osteotomy in mandibular prognathic patients with high value of gonial angle is effective to improvement of gonial angle, and In patients who have normal range of gonial angle and are required with excessive mandibular setback, short lingual cut method, additional resection of posterior margin of distal segment, Obwegeser II method will be considerd. 7. More prudent operation and careful post-op management will be responsible for maintenance of postoperative stable gonial angle.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.13 no.6
• /
• pp.521-528
• /
• 1988

Into the telecommunications industry, which had been monopolistic, a few advanced countries introduced competition through 70's and 80's. And this trend is going on worldwide. The introduction of competition into the industry is made mainly in the long distance, international and enhanced market. This liberalisation results from the fundamental change of the cost function. Suggesting that the cost comprises of that of the facility sector and that of the operation sector there exists the economies of scale in the facility sector in general. The major ground for the monopolistic industrial structure in the past was the natural monopoly depending on the economies of scale. But the rapid advance of the technology by a large margin. This decrease has resulted in the change of the cost function. That is while there exists the economies of scale in the smaller production scale, the average cost increases beyond a certain scale. This means that the natural monopoly collapsed, and that the competitive structure is more efficient than the monopolistic structure. But, because there exists economies of scale in the smaller scale, the desirable number of players, which could result in efficient industry structure depends on the market size. Such correlation between technological level market size and the degree of regulation is found in the case of U.S.A., Japan and U.K., where deregulation policy of the telecommunications market has already been carried out. In U.S.A., which has the largest market and the highest technological level the degree of regulation is lowest. Also in the order of Japan and U.K. the regulation is severer. Japan and U.K. are likely to liberalize still more, as the technology advances and the market grows. This article is just the beginning of the research, and this hypothesis requires more detailed research.

• Radiation Oncology Journal
• /
• v.21 no.2
• /
• pp.118-124
• /
• 2003

Purpose: The goal of this study was to determine the role of postoperative radiation therapy in extrahepatic bile duct cancers. Materials and Methods: Between 1997 and 2001, 41 patients with extrahepatic bile duct cancer having undergone surgical resection were retrospectively analyzed. Of the 41 patients, 22 were treated by surgery alone (Group I) with remaining 19 treated by surgery and postoperative radiation therapy (Group II). A gross total surgical resection with pathologically negative margins was peformed in 11 of the patients (50$\%$) in Group 1, and in 7 of the patients (36.8$\%$) in Group II. There were no significant differences in the disease stage, surgical procedure or pathological characteristics of the two groups. The patients in group II received 45$\~$54 Gy (median: 50.4 Gy) of external beam radiation therapy to the tumor bed and draining nodal area. Results: The local failure rate was significantly higher In group I (54.5$\%$) than in group II (15.8$\%$)(p=0.01). Of the 12 failed patients in Group I and the 3 failed patients in group II, 7 and 3 had a positive resection margin. The overall 3-year survival rates were 38.3 and 38.9$\%$ and the 3-year disease free survival rates were 18.8 and 26.3$\%$ in groups I and II, respectively. However, the patients with positive resection margins who received adjuvant radiation therapy had higher 3-year overall survival rates than those with surgery alone (36.4$\%$ vs. 24.2$\%$, p=0.06), and 3-year disease free survival rate was significantly higher in the group II patients who had positive margins compared with those in group I (25.0$\%$ vs. 18.2$\%$, p=0.04). Conclusion: Postoperative adjuvant radiation therapy appeared to reduce the incidence of local failure in patients with extrahepatic bile duct cancer, and might improve the survival rate in the patients with positive resection margins.

• The Korean Journal of Air & Space Law and Policy
• /
• v.23 no.2
• /
• pp.115-136
• /
• 2008

The development of the aviation technology is beyond the people's imagination. For example, with some exaggeration, If the autopilot engage upon take off, You will realize that you are on the centerline of the foggy JFK runway 13R after 15 hours with only once or twice of intervention. But the more aviation technology develops, the more responsible the pilot will be who has the final authority of the aviation safety. In the JAL 706 accident caused by unidentified reason, the pilot increased pitch abruptly and overrode the control from the autopilot. The result of this process made the death of a flight attendant and some injuries of a few passengers. The district court found the pilot not guilty at the first trial on the ground that the control override was not connected to the possibility of foresight and avoidance of the human death. The pilot was proved to be innocent through the analysis of the DFDR and ADAS that the override did not precede the unidentified pitch up motion. The judicial precedent related to aviation accidents in Korea requires pilots' absolute and extended care compared to the ordinarily prudent or reasonably careful behaviors in the vehicle and medical accidents. Although there is some controversy about the standard care, the care required in the actual operation of high tech aircraft by a pilot should include objective and standard care and be judged by analysis of the scientific data. Although the pilot maintained the unusual hi speed that doesn't have safety margin and descended under turbulence in case of the JAL 706 accident, the court negatived its relation to the cause of pitch up. Also, the override of the control after initial pitch up might have caused the possibility of the death and injury, but the court denied it. Because of this complex cause of the aviation accidents, it is important for a court to figure out the core reason of the event and casual relationship with the pilot Now, It is required that the judgement of negligence in the aviation accidents should include an objective care with scientific data from simulated circumstances(or a simulator) as the Japanese court not from the theory of vehicle's negligence.

• Journal of Gastric Cancer
• /
• v.8 no.4
• /
• pp.210-216
• /
• 2008

Purpose: Siewert's classification of adenocarcinoma of the esophagogastric junction (AEG) has been widely adopted, but there is a wide discrepancy of the clinicopathological features of AEG of the Asian patients as compared to that of the Western patients. The aim of this study was to investigate the clinicopathological characteristics of AEG according to the Siewert classification. Materials and Methods: Among the patients who underwent surgery for gastric carcinoma in our institution between May 2004 and February 2008, the AEG patients were selected based on their operation records and the photographs according to Siewert's classification. Results: There were 70 AEG patients (3.9%) among the total of 1,778 patients. There were 3 patients (4.3%) with type I, 30 patients (42.8%) with type II and 37 patients (52.8%) with type III. Curative resection (R0) was achieved in 68 cases (97.1%). No significant differences in gender, stage, Barrett's esophagus and the proximal margin were found between the patients with type II and type III AEG. The patients with type III were younger than the patients with type II (59 vs 64 years, respectively, P=0.049). Well differentiated histology (P=0.045) and the intestinal type (P=0.055) were significantly more frequent in the patients with type II as compared with that in the patients with type III. Conclusion: There was a striking difference of the Asian patients from the Western patients for the incidence of AEG (and especially type I). Some of the differences between type II and type III patients were similar to those of the previous Western studies. A large study is needed to investigate whether these features are typical in the Korean population.

• Radiation Oncology Journal
• /
• v.9 no.2
• /
• pp.285-291
• /
• 1991

One hundred and twenty six patients with early uterine cervical cancer who had been treated at Departmen of Radiation Oncology of Korea University Hospital from Jan.1981 to Dec.1988 were analysed retrospectively by the treatment result and pattern of of failures. All patients had stage Ia to IIa disease and were grouped whether they had combination of operation and postop irradiation or radiation therapy alone. 1) Sixty six patients belonged to the combination treatment group and 60 patients to the radiation alone group. 2) Combination group consisted of $18.1\%$(12/66) stage Ia, $71.2\%$(47/66) stage Ib and $10.6\%$ (7/66) stage IIa patients. There were no stage Ia, 18.8$\%$(l1/60) stage Ib and 81.6$\%$(49/60) stage IIa patients for RT alone gronp. 3) There were total 23$\%$(29/126) treatment failures,13 patients in combination group and 16 patients in RT alone group. In 66 patients of combination group, they were found to have 5 locoregional failures, 7 distant failures and 1 at both sites. In 60 patients of RT alone group, 9 locoreginal failure and 7 distant failures occured. Eighty six percent (25/29) of total failures appeared within 18 month after completion of treatment. About 60$\%$ of the patients with regional recurrences which were located at pelvic side wall or pelvic lymph nodes paesented their recurrent disease after 1 year of completion of treatment, whereas same percent of distant failures appeared within 6 month. 5) In RT alone group, the first sites of distant failure were mostly para-aortic lymph node and/or left supraclavicular lymph node (71.4$\%$,5/7). In combination group, various sites such as inguinal lymph node, mediastinal lymph node, liver, lung and bone appeared first or at the same time with para-aortic and supraclavicular lymph node metastasis. 6) Logistic regression analysis was done for multivariate analysis of the factors contributing to locoregional and distant failures. In combination group, adequacy of the resection margin and the presence of positive pelvic node were found to be the most significant factors (p=0.0423 & 0.0060 respectively). In RT alone group, less than complete regression of the tumor at the end of treatment was the only significant contributing factor for the treatment failures (p=0.0013) with good liklihood ratio.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.30 no.1
• /
• pp.127-134
• /
• 2024

With the growth of offshore wind power generation market, the corresponding installation vessel market is also growing. It is anticipated that approximately 100 installation vessels will be required in the of shore wind power generation market by 2030. With a price range of 300 to 400 billion Korean won per vessel, this represents a high-value market compared to merchant vessels. Particularly, the demand for large installation vessels with a capacity of 11 MW or more is increasing. The rapid growth of the offshore wind power generation market in the Asia-Pacific region, centered around China, has led to several discussions on orders for operational installation vessels in this region. The seabed geology in the Asia-Pacific region is dominated by clay layers with low bearing capacity. Owing to these characteristics, during vessel operations, significant spudcan and leg penetration depths occur as the installation vessel rises and descends above the water surface. In this study, using penetration variables ranging from 3 to 21 m, the unique vibration period, structural safety of the legs, and conductivity safety index were assessed based on penetration depths. As the penetration depth increases, the natural vibration period and the moment length of the leg become shorter, increasing the margin of structural strength. It is safe against overturning moment at all angles of incidence, and the maximum value occurs at 270 degrees. The conditions reviewed through this study can be used as crucial data to determine the operation of the legs according to the penetration depth when developing operating procedures for WTIV in soft soil. In conclusion, accurately determining the safety of the leg structure according to the penetration depth is directly related to the safety of the WTIV.