• Korean Journal of Radiology
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• 제25권8호
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• pp.756-766
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• 2024

Objective: To evaluate the efficacy and safety of thermal ablation in treating solitary low-risk T2N0M0 papillary thyroid cancer (PTC) and compare the outcomes of microwave ablation (MWA) and radiofrequency ablation (RFA). Materials and Methods: This retrospective, single center study involved 34 patients (age: 40.0 ± 13.9 years; 28 female) who had low-risk T2N0M0 PTC with a maximum diameter >2 cm and ≤4 cm and underwent MWA (n = 15) or RFA (n = 19) from November 2016 to April 2023. The primary outcomes were the cumulative rate of disease progression and delayed surgery rates. In contrast, the secondary outcomes included changes in tumor size, cumulative rate of complete tumor disappearance, and complication rates. Results: The median follow-up period was 18.0 months (interquartile range [IQR]: 9.0-40.0 months). At 12 months, the median volume reduction rate of the ablation zone was 74.2% (IQR: 53.7%-86.0%). Disease progression was noted in two patients within 1 year, including one patient with local tumor progression post-RFA and one with a new tumor post-MWA, resulting in a constant cumulative disease progression rate of 8.8% (95% confidence interval [CI]: 0%-19.8%) throughout the remaining follow-up period. Both patients were subsequently treated with additional ablation and did not require surgery. The cumulative rates of complete tumor disappearance at 1, 3, and 5 years were 4.0% (95% CI: 0%-11.4%), 26.8% (95% CI: 2.7%-44.9%), and 51.2% (95% CI: 0%-79.1%), respectively. No significant differences were observed in the disease progression (P = 0.829) or complete tumor disappearance (P = 0.633) rates between the MWA and RFA groups. Complications occurred in 14.7% (5/34) of patients presenting with transient hoarseness. RFA had a higher but not statistically significant complication rate than MWA did (21.1% [4/19] vs. 6.7% [1/15]; P = 0.355). Conclusion: Both MWA and RFA demonstrated promising short-term outcomes in terms of efficacy and safety in treating solitary low-risk T2N0M0 PTC, with no significant differences.

• The Journal of Asian Finance, Economics and Business
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• 제7권4호
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• pp.163-171
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• 2020

The study aims to examine the effects of inward every presence of foreign investment, import, and real exchange rate shocks on export performance in Vietnam. This study employs a time-series sample dataset in the period of 2009 - 2018. All data are collected from the General Statistics Office of Ministry of Planning and Investment in Vietnam, World Development Indicator and Ministry of Finance, State Bank of Vietnam. This study employs the Augmented Dickey-Fuller test and the vector error correction model with the analysis of cointegration. The results demonstrate that a higher value of import significantly accelerates export performance in the short run, but insignificantly generates in the long run. When the volume of registered foreign investment goes up, the export performance will predominantly decrease in the both short run and long run. Historically, countries worldwide are more likely to devaluate their currencies in order to support export performance. According to the study, the exchange rate volatility has an effect on the external trade in the long run but no effect in the short run. Finally, Vietnam's export performance converges on its long-run equilibrium by roughly 6.3% with the speed adjustment via a combination of import, every presence of foreign investment, and real exchange rate fluctuations.

• 한국전자파학회논문지
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• 제23권11호
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• pp.1272-1279
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• 2012

본 논문에서는 기상청의 10년간의 1분 단위 강수량 측정 데이터를 이용하여 국내 환경에 대한 연평균 강우율 분포 및 강우율 분포와 최악월 강우율 분포의 상관 관계 모델을 제시하였다. 본 논문에서 제시한 모델을 기존의 ITU(International Telecommunication Union)-R 권고 모델과 비교한 결과, 시간율 0.01 %에 대해서 국내 연평균 강우율의 전국 평균값은 ITU-R 권고 문서의 강우율에 비하여 약 28 % 높게 나타났다. 또한, 연평균 및 최악월 강우율 분포 간의 상관 관계도 본 논문의 모델과 ITU-R 권고 문서의 모델은 상당히 큰 차이를 보였다. 앞으로 국내 무선 통신 시스템 설계에 필수적인 강우 감쇠의 통계적 특성(시간율 분포) 계산을 위해서는 국내 환경에 적합한 강우율 분포 모델을 사용하여야 할 것으로 판단된다.

• Journal of Welding and Joining
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• 제32권3호
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• pp.74-80
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• 2014

Due to environmental regulations (RoHS, WEEE and ELV) of the European Union, electronics and automotive electronics have to eliminate toxic substance from their devices and system. Especially, reliability issue of lead-free solder joint is increasing in car electronics due to ELV (End-of-Life Vehicle) banning from 2016. We have prepared engine control unit (ECU) modules soldered with Sn-40Pb and Sn-3.0Ag-0.5Cu (SAC305) solders, respectively. Degradation characteristics of solder joint strength were compared with various conditions of automobile environment such as cabin and engine room. Thermal cycle test (TC, $-40^{\circ}C$ ~ ($85^{\circ}C$ and $125^{\circ}C$), 1500 cycles) were conducted with automotive company standard. To compare shear strength degradation rate with eutectic and Pb-free solder alloy, we measured shear strength of chip components and its size from cabin and engine ECU modules. Based on the TC test results, finally, we have known the difference of degradation level with solder alloys and use environmental conditions. Solder joints degradation rate of engine room ECU is superior to cabin ECU due to large CTE (coefficient of thermal expansion) mismatch in field condition. Degradation rate of engine room ECU is 50~60% larger than cabin room electronics.

• 한국산학기술학회논문지
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• 제13권9호
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• pp.4284-4293
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• 2012

건설사업 수행의 초기단계에서 가장 중요한 과제는 적정 예정공사비를 산정하는 일이다. 따라서 본 연구에서는 공동주택 건설사업 초기단계에서 합리적이고 정확한 토목공사비의 예측을 위하여 170개의 공사비자료를 활용한 회귀분석을 실시하였고, 종속변수인 토목공사비를 지역위치에 따른 전국, 부지조건에 따른 사유지, 조합부지, 공공부지로 구분하여 다양한 분석을 함으로써 예측모델의 이용의 편리성과 정확성을 높였다. 회귀식을 이용한 공동주택 토목공사비의 예측 결과 오차율은 전국 적용 예측모델 15.59%, 사유지 적용 예측모델 17.53%, 조합부지 적용 예측모델 21.86%, 공공부지 적용 예측모델 13.08%로 나타났다.

• 산경연구논집
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• 제9권3호
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• pp.57-68
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• 2018

Purpose - The purpose of this study is to classify that the quality factors for comparing the Visegrard Group with the Nordic Council have historical similarities against Germany and the Soviet Union. However, this is because in the integrated European market, the competitiveness possessed by the two groups of countries is invested in the priority order to grow. Research design, data, and methodology - The study was conducted on the research design, and the reason for trying to compare the competence of the automobile industry in the assessment of industrial capability is that the Visegrard Group focuses on automotive production and the Nordic Association focuses on the commercialization of the automobile(market). In this study, searching and quantifying indirect evidence was made through standards are more complementary in Europe since each country acts like the role of the European automotive industry for example, which is different from the realistic evaluation criteria, are more important than those of the United States(first in the world) or Germany(first in Europe). Results - The results of this study are as follows: In the global EV market U.S.(export: $ 2.62 billion /share: 36.7%), Germany($ 1.29 billion /18.1%), France($ 390 million /5.4%), United Kingdom($ 380 million /5.4%), and South Korea($ 320 million/ 4.4%). South Korea's share of the EV market is 4.4%, while TSI reaches at +0.9 which measures the comparative advantage of a specific commodity in the world trade market. There is great potential for evaluated as products processing in export competition. But, commercialization, standardization, and overall market expansion did not have a positive impact on global satisfaction. Conclusions - EVs put importance on various utilities. So this suggests that Korea's exports to the EU, including the Visegrard Group, should be more focused on marketability when illuminating with a sharing industrial system under the European Union. It is necessary to specialize in manufacturing and commercialization by country(region) to prepare sharing economy and blockchain in order to create a smart-sharing city linked on artificial intelligence, as the commercialization of electric vehicles, which will have a larger growth rate than that of manufacturing in the fourth revolutionary era.

• 대한족부족관절학회지
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• 제9권1호
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• pp.105-109
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• 2005

Purpose: We compared the clinical features of the ankle fractures treated by operation between the elderly and the young, and reviewed the principles of treatment of the ankle fractures in the elderly. Materials and Methods: We reviewed 49 cases of the ankle fractures, which were treated by open reduction from August 1991 to July 2002. Patients aged more than 60 were designated as the elderly, and patients aged between 15 and 33 were designated as the young. The average follow-up period was 13.2 months. Using the Lauge-Hansen classification, We defined stage I or II fractures as low stage and stage III or IV fractures as high stage fractures. Results: There were 15 cases of high stage fractures (78.9%) in the elderly and 11 cases (36.7%) in the young. High stage fracture rate was significantly higher in the elderly (P=0.004). Hospital day, period between primary injury and operation, and union time were significantly longer in the elderly (P<0.001). However, there was no statistical difference in immobilization time between the two groups. The results of treatment were satisfactory clinically and radiologically by the Meyer's criteria in both groups. Conclusion: In the elderly, high stage fractures were more common and longer hospitalization and union time were needed than the young. However, the result of surgical treatment was satisfactory.

• Archives of Reconstructive Microsurgery
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• 제1권1호
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• pp.31-38
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• 1992

The management of giant cell tumor involving juxta-articular portion has always been a difficult problem. In certain some giant cell tumors with bony destruction, a wide segmental resection may be needed for preventing to recur. But a main problem is preserving of bony continuity in bony defect as well as preservation of joint function. The traditional bone grafts have high incidence in recurrence rate, delayed union, bony resorption, stress fracture despite long immobilization and stiffness of adjuscent joint. We have attemped to overcome these problems by using a microvascular technique to transfer the fibula with peroneal vascular pedicle as a living bone graft. From Apr. 1984 to Nov. 1990, we performed the reconstruction of wide bone defect after segmental resection of giant cell tumor in 4 cases, using Vascularized Fibular Graft, which occur at the distal radius in 3 cases and at the proximal tibia in 1 case. An average follow-up was 2 years 8 months, average bone defect after wide segmental resection of lesion was 11.4cm. These all cases revealed good bony union in average 6.5months, and we got the wide range of motion of adjacent joint without recurrence and serious complications.

• Clinics in Shoulder and Elbow
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• 제18권3호
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• pp.128-132
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• 2015

Background: We described a surgical method for osteosynthesis and reported the resultant strength after application of a PHILOS plate through the anterolateral approach for the treatment of fractures of the distal humerus. Methods: Between February 2010 and March 2012, open reduction and internal fixation operations with the PHILOS plate for treatment of fracture of the distal humerus were performed on a total of nine patients (five men, four women). The mean age was 40.8 years (range, 24-50 years), and the average follow-up period was 9.1 months (range, 6-15 months). Clinical evaluations were performed 6 months after the operation. Clinical assessment included determination of the range of motion of the elbow, the Mayo and Oxford elbow scores, and any postoperative complications. Results: Fracture union was noted in all patients, with an average period of 12.4 weeks. The average Mayo elbow and Oxford elbow scores were 87.2 (of a total of 100) and 43.3 (of a total of 48), respectively. For the postoperative range of motion of the elbow, all patients showed complete recovery to the preoperative range of motion. No other conditions, such as neurolepsis, plate breakage, or rotational deformity, were observed. Conclusions: Open reduction and internal fixation of distal humerus fractures with a PHILOS plating system via anterolateral approach can be effective. A high rate of union with good outcomes can be assumed.

• Journal of Yeungnam Medical Science
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• 제23권2호
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• pp.152-161
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• 2006

담낭암은 조기에 진단되지 않아 예후가 아주 나쁜 소화기암 중의 하나로, 담낭암 발생의 위험성을 예견한 담낭절제술의 대상을 정확히 규명하는 것이 중요하다. 담낭 용종의 크기, 개수, 담석의 유무, 환자의 나이가 담낭암 발생과 관련된 인자이며, 용종 크기 1 cm 이상, 동반된 담석증, 50세 이상, 증상이 있을 때, 관찰 기간 중 급격한 크기 변화가 있을 때 수술을 권하는 것이 좋을 것으로 판단되며, 췌담관 합류 기형이 발견되면 담낭을 반드시 절제 하여야 하며 수술 전 및 수술중 담낭암의 존재 여부를 세밀히 조사하는 것이 좋겠다. 만성 담낭염에서 보이는 담낭 점막의 화생 변화는 전암 병변으로 생각이 되며, 담낭염의 변종으로 생기는 황색육아종성 담낭염, 도재담낭 및 담낭 장관루 등에서 고빈도로 담낭암이 발생하고 있어, 염증성 변화 및 이의 지속되는 기간과 암 발생과는 밀접한 관계가 있을 것으로 사료 된다.