• Archives of Plastic Surgery
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• 제50권5호
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• pp.507-513
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• 2023

Background Free tissue transfer is considered the gold standard option for the reconstruction of distal leg defects. Free tissue transfer using recipient vessels in the contralateral leg (cross-leg bridge) is a potential option to supply the flap if there are no suitable recipient vessels in the injured leg. Most studies have described this technique using end-to-end anastomosis which sacrifices the main vessel in the uninjured leg. This study evaluated the use of a cross-leg free latissimus dorsi muscle flap for the reconstruction of defects in single-vessel legs, using end-to-side anastomosis to recipient vessels in the contralateral leg without sacrificing any vessel in the uninjured leg. Methods This is a retrospective study that included 22 consecutive patients with soft tissue defects over the lower leg. All the reconstructed legs had a single artery as documented by CT angiography. All patients underwent cross-leg free latissimus dorsi muscle flap using end-to-side anastomosis to the posterior tibial vessels of the contralateral leg. Results The age at surgery ranged from 12 to 31 years and the mean defect size was 86 cm². Complete flap survival occurred in 20 cases (91%). One patient had total flap ischemia. Another patient had distal flap ischemia. Conclusion Cross-leg free latissimus dorsi muscle flap is a reliable and safe technique for the reconstruction and salvage of mutilating leg injuries, especially in cases of leg injuries with a single artery. As far as preservation of the donor limb circulation is concerned, end-to-side anastomosis is a reasonable option as it maintains the continuity of the donor leg vessels.

• Journal of Chest Surgery
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• 제21권6호
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• pp.1030-1039
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• 1988

From 1985 through Oct. 1988, we have experienced 5 cases of Aorto-Coronary Bypass Surgery [ACBS] and 3 cases of Percutaneous Transluminal Coronary Anogioplasty [PTCA]under the diagnosis of unstable angina. There were 6 males and 2 females who ranged from 48 to 70 years old. Almost all patients had a evidence of hypertension & hyperlipidemia. Two patients showed old myocardial infarction and remaining patients showed myocardial ischemia on resting state. The patterns of involvement of coronary artery disease were single vessel disease [4 cases], double vessel disease [3 cases], Triple vessel disease [1 case]. Among 5 cases of ACBS, double bypass graft was in 3 cases and single bypass graft was in 2 cases. Mode of anastomosis were all individual anastomosis, using Saphenous vein graft. Postoperative complications were perioperative myocardial infarction [2 cases], postoperative bleeding [1 case], leg wound disruption [1 case]. Perioperative myocardial infarction cases didn*t survive. In cases of PTCA, there were no complications. Follow up periods were ranged from 1 month to 25 months. All survived cases were asymptomatic except one case, who showed Functional Class II.

• 한국해양공학회지
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• 제29권2호
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• pp.135-142
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• 2015

The float over method is the most preferred method for installing heavy topside onto a jacket platform. A very complex platform with multiple jacket structures on a specific field requires multiple installation procedures. This study validated the installation of two topsides using a single installation barge to reduce the operation and installation cost. The hydrodynamic properties of the installation barge during the installation of two topsides were calculated. The tension and fender forces during docking were investigated to show the validity of the proposed dual topside installation method. In conclusion, the operational safety of the proposed procedure was validated through the calculation of the motion of the installation vessel and loads on the jacket legs.

• 설비공학논문집
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• 제29권12호
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• pp.654-662
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• 2017

When emergency core cooling system (ECCS) is operated during loss of coolant accident (LOCA) in a pressurized water reactor (PWR), pressurized thermal shock (PTS) phenomenon can occur as cooling water is injected into a cold leg, mixed with hot primary coolant, and then entrained into a reactor vessel. Insufficient flow mixing may cause temperature stratification and steam condensation. In addition, flow vibration may cause thermal stresses in surrounding structures. This will reduce the life of the reactor vessel. Due to the importance of PTS phenomenon, in this study, calculation was performed for Test 1 among six types of OECD/NEA ROSA tests with ANSYS CFX R.17. Predicted results were then compared to measured data. Additionally, because temperature difference between the hot coolant at the inlet of the cold leg and the cold cooling water at the inlet of the ECCS injection line is 200 K or more, buoyancy force due to density difference might have significant effect on thermal-hydraulic characteristics of flow. Therefore, in this study, the necessity to include buoyancy force term in governing equations for accurate prediction of single phase thermal stratification in both cold legs and downcomer by ECCS injection was numerically studied.

• 해양환경안전학회지
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• 제27권6호
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• pp.846-855
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• 2021

최근 친환경, 신재생 에너지 수요에 따라서 해상풍력발전 분야는 빠른 성장세와 설비의 대형화에 따른 전용설치선박의 관련 기술개발이 요구되고 있다. 해상풍력설치선박(WTIV: Wind Turbine Installation Vessel)은 설치 작업 시 선체를 파도의 영향을 받지 않는 높이로 이동시키고 모든 환경하중은 레그가 담당한다. 특히 파랑하중은 불규칙파로 구성되어 있기 때문에, 정확한 동적응답특성을 파악하는 것은 아주 중요한 문제이다. 이러한 동적응답해석은 간이법의 하나인 단자유도법을 널리 활용하고 있으나, 불규칙 파를 고려하지 못하는 제약조건이 있다. 따라서 현재 설계 시 불규칙 파에 대한 시간영역 계산이 가능한 다자유도 계산법을 사용하고 있다. 그러나 다자유도 계산법에서 시간영역 해석은 정도 높은 계산 결과를 제공하지만, 데이터의 수렴도가 민감하고 복잡성에 있어 설계 시 어려움이 있다. 따라서 본 논문은 다양한 변수를 기준으로 한 시간영역 해석을 통하여 불규칙 파의 동적응답 특성을 표현 할 수 있는 동적증폭계수 추정식을 개발하였다. 기존 다자유도 모델 대비 계산시간 단축 및 정확도 확보를 확인하였다. 개발된 동적증폭계수 추정식은 WTIV 및 유사 구조물 설계에 활용이 가능할 것으로 판단된다.

• Archives of Plastic Surgery
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• 제47권2호
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• pp.165-170
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• 2020

Background Perforator mapping has been well described in the literature. Once the suprafascial plane is reached, the course of perforators is considered constant. However, the surgeon must be aware of whether an anastomosis exists between perforators superficially to the fascia, in order to choose the best vessel upon which to base the reconstruction. Our retrospective in vivo anatomical study of lower leg perforator flaps presents the first description of variations in the suprafascial path of perforators, which may influence preoperative flap design. Methods An anatomical study of lower limb perforators was performed on 46 nonconsecutive patients who were referred to our department from June 2012 to October 2018. Reconstruction with perforator-based propeller flaps was planned for each of the patients. In total, 72 perforators were preoperatively identified and surgically isolated. The suprafascial course of each perforator was reported. Results During suprafascial surgical exploration, branching patterns were observed in four perforators. These perforators had been classified as single vessels in the preoperative ultrasonographic analysis. However, after surgical dissection, distal converging branches were noted in two of them. Conclusions Our study is the first description in the literature of suprafascial converging perforators, which might constitute an obstacle to planned reconstruction procedures. Despite the accuracy of preoperative evaluations, anatomical variations were present. Knowledge of suprafascial perforator variations may help surgeons to choose the correct perforator upon which to base a planned flap.

• 대한의용생체공학회:의공학회지
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• 제41권5호
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• pp.173-178
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• 2020

Remote control intervention surgery robotic system improves treatment effect on cardiovascular patients and reduces X-ray exposure. However, at the time of the first procedure, CT (computerized tomography) and other ultrasound diagnostic equipment should be used because the operator must insert the cannula directly into the patient's leg. Improvements to this have been un-met-needs of hospitals. In this paper, we developed a system that can insert the cannula intuitively and quickly by displaying blood vessels at a glance through the system using smart wearable glasses. The core development method is as follows. In order to project augmented reality onto the surgical image, CT scan angiography image is extracted and processed. In the process, three CT-Markers are used to create a coordinate system of blood vessel images. Additionally, a reference marker is photographed on a single camera to obtain a camera coordinate system. Since the CT marker and the reference marker are in the same position, 3D registration is performed. In the text, a detailed explanation will be given.

• Nuclear Engineering and Technology
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• 제55권5호
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• pp.1651-1664
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• 2023

It is very difficult to capture the multi-dimensional phenomena such as asymmetric flow and temperature distributions with the one-dimensional (1D) model, obviously, due to its inherent limitation. In order to overcome such a limitation of the 1D representation, many state-of-the-art system codes have equipped a three-dimensional (3D) component for multi-dimensional analysis capability. In this study, a standard multi-dimensional analysis model of APR1400 (Advanced Power Reactor 1400) has been developed using TRACE (TRAC/RELAP Advanced Computational Engine). The entire reactor pressure vessel (RPV) of APR1400 has been modeled using a single 3D component. The fuels in the reactor core have been described with detailed and coarse representations, respectively, to figure out the impact of the fuel description. Using both 3D RPV models, a comparative analysis has been performed postulating a double-ended guillotine break at a cold leg. Based on the results of comparative analysis, it is revealed that both models show no significant difference in general plant behavior and the model with coarse fuel model could be used for faster transient analysis without reactor kinetics coupling. The analysis indicates that the asymmetric temperature and flow distributions are captured during the transient, and such nonuniform distributions contribute to asymmetric quenching behaviors during blowdown and reflood phases. Such asymmetries are directly connected to the figure of merits in the LBLOCA analysis. Therefore, it is recommended to employ a multi-dimensional RPV model with a detailed fuel description for a realistic safety analysis with the consideration of the spatial configuration of the reactor core.

• 대한약침학회지
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• 제7권2호
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• pp.65-73
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• 2004

Objective : This study was to review on the prostate disease-related studies with Acupuncture therapy in renowned medical internet site of PubMed, and to make master plan of the study, especially, on Bee Venom Acupuncture(BVA) of Prostate disease and then to devise the idealistic therapeutic ways of it. Method : We made the internet search with the key words of bee venom(bee venom therapy, apitoxin, apitherapy, bee sting, bee sting therapy), acupuncture, prostate, prostatitis, prostrate cancer in Pubmed, from June 1st to July 1st,2004. Results : 1.25 papers were found in 19 publised jounals. of which two named'Urology'and Prostate' had three papars, two called 'JUrology' and 'Cancer Immunol Immunother' had two papers, and the others had a paper respectively. 2. In the classification by papers' types, Review papers were 8 and Original were 17 where there were 5 clinical trials, 11 experimental studies and 1 epidemiologic paper. Of 5 clinical trials, 2 belonged to Randomized Control Study, and of 11 experimental studies, 4 belonged to in vitro and 7 belonged to in vivo with in viro studies, and 1 epidemeologic belonged to meta-analysis. 3. In the classification by prostate diseases, 4 were about prostatitis, 3 were about prostate related symptoms, 16 were about prostate cancer, and two were about the others. 4. In the classification by applied treatment methods, 5 were related with Acupuncture, 10 were related with BVA(Bee Venom, Bee), and 10 were related with the others. Of 5 related with Acupuncture, 3 used general acupuncture, 1 used electrical acupuncture, and 1 used general acupuncture and electrical acupuncture at the same time. 5. In 2 RCTs of Clinical trials, Control group was set up to the group using different compatible treatment method or using meridians not related with treating prostate disease. Single or double blind methods couldn't be found. 6. In the clinical trials, IPSS, NIH, CPSI or subjective global assessment were used as the Index of Evaluation. 7. The Leg Greater Yang Bladder Meridian(B), The Leg Lesser Um Kidney Meridian(K) and Conception Vessel Meridian(CV) were used as major meridians, and B10(Taejo, Dazhu), B23(Shinsu, Shenshu), B28(Panggwangsu, Pangguangshu), B35(Hoeyang, Huiyang), B39(Wiyang, Weiyang), B40(Wijung, Weizhong), B54(chilbyon, Zhibian), K1(Yongchon, Yongquan), K10(Umgok, Yingu), CV3(Chungguk, Zhongji), CV4(Kwanwon, Guanyuan),S6(Hyopko, Jiache) were used as acupoints. Electrical acupuncture(EA) was considered to be more important and CV3(Chungguk, Zhongji), CV4(Kwanwon, Guanyuan) were mainly selected as EA applied acupoints. 8. It is mostly said that Acupuncture appeared to be a safe, effective, and durable treatment alternative in improving symptoms of patients with prostate diseases, refractory to conventional medicine. A larger controlled study was required to confirm these encouraging initial results. Conclusion : Papers about BVA of Prostate cancer or Prostatitis were not found, and low permeability of Prostate is concerned, BVA with the anti-inflammatory and anti-cancer effect can be adopted as a new alternatives of Prostate disease treatment, so it is thought that Study of how to make access to prostate, animal experiment including in vivo and in vitro and more clinical trials with using acupoints on related meridian should be followed.