• Archives of Plastic Surgery
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• 제33권3호
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• pp.289-293
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• 2006

By means of microsurgical free-tissue transfer providing a large amount of required tissue, the surgeon can resect tumoral tissue more safely, which allows tumor-free margins and enhances the reliability of the ablative surgery that otherwise could not be performed radically. The morbidity of elective free-tissue transfer seems to be quite low, carrying acceptable risks for most patients. But the elderly patients are at risk for cardiac and respiratory problems, deep vein thrombosis, pulmonary emboli and infection merely as a function of age. This study was undertaken to define further risks of the elderly population with regards to free-tissue transfer. We retrospectively reviewed our experience with 110 microsurgical free-tissue transfers for head and neck reconstruction in patients greater than 60 years of age. Microsurgical procedures in all cases were preformed by the plastic and reconstructive department at Yonsei medical center. The investigated parameters were patient demographics, past medical history, American Society of Anesthesiologists(ASA) status, site and cause of defect, the free tissue transferred and postoperative complication including free-flap success or failure. There were 46 patients in the age group from 60 to 64 years, 34 patients from 65 to 70 years, and 30 patients 70 years or older. There happened 3 flap losses, resulting in a flap viability rate of 97%. Patients with a higher ASA designation experienced more medical complication(p=0.05, 0.01, 0.03 in each age group I, II, III) but not surgical complication p=0.17, 0.11, 0.54 in each age group I, II, III). And the relationship between postoperative complication and age groups was not significant. These observations suggest that major determinant for postoperative medical complication be the patient's American Society of Anesthesiologists score, and chronologic age alone should not be an exclusion criterion when selecting patients for free-tissue transfer

• Archives of Reconstructive Microsurgery
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• 제21권1호
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• pp.56-60
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• 2012

Purpose: Thumb reconstruction plays most important role in hand injuries because total loss of a thumb constitutes about 40% disability in the hand. The reconstruction can be accomplished by pollicization, free toe-to-thumb transfer, wrap around procedure and lengthening extraction. However, we sometimes need consecutive or double free flaps in the reconstruction of mutilating hand injuries. Methods: We reconstructed a mutilating hand injury in a 54-years old man. Because of severe crushing injury of right thumb and index fingers, we reconstructed a thumb with pollicization using nearly amputated middle finger. Although it survived completely, the adjacent soft tissues which had been covered by fillet flap from the space past was necrosed on 1 month. We debrided the necrotic tissues and covered it with anteromedial thigh perforator free flap consecutively because he had an anatomical variation in branches of lateral femoral circumflex artery. Results: He had an uneventful postoperative course without any complication such as infection, dehiscence and flap necrosis. Three months later, he had undergone tenolysis and defatting procedure of flap site. He recovered the some amount of grip function and was happy with the result. Conclusion: In severe hand trauma including thumb amputation, thumb reconstruction using pollicization and perforator free flap could be an alternative option. It provides minimal donor site morbidity and an acceptable functional result.

• 물과 미래
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• 제15권3호
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• pp.23-36
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• 1982

The stochastic variations and structures of time series data on water quality were examined by employing the techniques of autocorrelation function, variance spectrum, Fourier series, autoregressive model and ARIMA model. These time series included hourly and daily observation on DO, turbidity, conductivity pH and water temperature. The measurement was made by automatic recording instrument at Noryangjin and Dook-do located in the downstream part of Han River during 1975 and 1976. Hourly water quality time series varied with the dominant 24-hour periodicity, and the 12-hour periodicity was also observed. An important factor affecting 24-hour periodic variation of DO is believed to be photosynthesis by algae. These phenomena might be attributable to periodic discharges of municipal sewage. Noryangjin site showed the more distinct 12-hour periodicity than Dook-do site did, and tidal effect might be responsible for the difference. The water quality, as measured by DO and turbidity, was better in the afternoon compared with the quality in the morning. This change can be explained by the periodic variation of DO, temperature and the amount of municipal wewage discharge. It was also observed that the water temperature at Noryangjin was higher than the temperature at Dook-do. This difference might have been caused by the pollutants that were added to the section between two sites. The correlation coefficients between some of the variables were fairly high. For example, the coefficient was -0.88 between DO and water temperature, 0.75 between turbidity and river flow, and 0.957 between water temperature and air temperature. The lag time of heat transfer from the air to the water was estimated as 24 days. The first order auto-regressive model was appropriate for explaning standardized hourly DO time series. The ARIMA model of (1, 0, 0) type provided relatively satisfactory results for daily DO time series after the removal of significant harmonic value.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 추계학술대회 논문집
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• pp.1877-1882
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• 2007

The Yongsan International Business District development work is a 20 billion$ project to raise facilities for national business, trade, residence, and culture. The project site is $566,800m^2$ and it covers the railroad maintenance center and Dongbuichon-dong. Developing railroad station region used to be done by private investment. However, problems existed; simple function as a massive selling market, traffic jam caused by massive market users, inadequacy to transfer to other transportations, interruption of the pedestrian way and separation of zone of life by the station. To solve this problem it is important to consider developing cases of other countries and devise a plan that is applicable to our circumstances. In the study, we compared our station development case with foreign station development cases and analyze the element for the plan what we should consider in our station development. In addition, The results of the study can be used as a preliminary data in the future planning the Yongsan International Business District development.

• 한국인터넷방송통신학회논문지
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• 제13권5호
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• pp.101-105
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• 2013

본 논문은 셀 사이트에서 다양한 트래픽을 수용하기 위한 이동 백홀 네트워크에서 QoS 기능에 관한 것이다. RAN 시스템의 스위칭 기능에 할당된, 이더넷 프레임, IP 패킷, 그리고 ATM 셀과 같은 트래픽은 세그먼트된 후 이동백홀 네트워크로 전달되기 전에 캡슐화 된다. ISP는 표준의 pseudowire 캡슐화를 통하여 all IP RAN 상에 음성 및 HSPA와 같은 모든 세대의 트래픽을 통합할 수 있다. 이것들은 다양한 QoS 방법뿐만 아니라 포괄적인 모니터링 및 진단 능력을 통하여 강화될 수 있다. 따라서 본 논문에서는 이와 같은 동작상에서 QoS 기능들이 서로 다른 갭슐 방법에 따라 시뮬레이션 되었다.

• Geomechanics and Engineering
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• 제6권6호
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• pp.531-544
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• 2014

Studies of earthquakes over the last 50 years and the examination of dynamic soil behavior reveal that soil behavior is highly nonlinear and hysteretic even at small strains. Nonlinear behavior of soils during a seismic event has a predominant role in current site response analysis approaches. Common approaches to ground response analysis include linear, equivalent linear and nonlinear methods. These methods of ground response analysis may also be categorized into time domain and frequency domain concepts. Simplicity in developing analytical relations and accuracy in considering soils' dynamic properties dependency to loading frequency are benefits of frequency domain analysis. On the other hand, nonlinear methods are complicated and time consuming mainly because of their step by step integrations in time intervals. In part Ι of this paper, governing equations for seismic response analysis of surcharged and layered soils were developed using fundamental of wave propagation theory based on transfer function and boundary conditions. In this part, nonlinear seismic ground response is analyzed using extended HFTD method. The extended HFTD method benefits Newton-Raphson procedure which applies regular iterations and follows soils' fundamental stress-strain curve until convergence is achieved. The nonlinear HFTD approach developed here are applied to some examples presented in this part of the paper. Case studies are carried in which effects of some influencing parameters on the response are investigated. Results show that the current approach is sufficiently accurate, efficient, and fast converging. Discussions on the results obtained are presented throughout this part of the paper.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제16권2호
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• pp.113-121
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• 1994

Large oral defects following tumor resection pose formidable challenge for the reconstructive surgeon. Ideally, wound closure should utilize like tissue in providing expedient, single-stage closure, returning maximum function while minimizing deformity. Recent methods have reported and utilize variable mucocutaneous flaps. However, the ideal reconstruction has yet to defined. The small bowel serves as a readily available donor site for satisfying reconstructive needs in oropharyngeoesophageal defects. Segments of jejunum may be opened along the antimesenteric border and transferred to oral defect as free tissue transfers. Some of the benefits of this technique have included a one-stage procedure, abundant donor tissue with characteristics similar to oral mucosa, near normal facial appearance, preservation of maximum tongue function and relief of annoying xerostomia by jejunal mucous secretion. Three cases re presented in which two cases show successful use of this flap. The other one patient developed total necrosis of this flap. We report cases of reconstruction using free jejunal flap transfer in oral reconstruction.

• 생명과학회지
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• 제14권5호
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• pp.752-760
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• 2004

Nitrogenase 촉매에서 Fe-단백질을 포함하는 [4Fe-4S] 클라스터의 기능은 기질의 결합과 환원 자리를 포함하는 MoFe-단백질로 핵산 의존 전자 주개로 작용하는 것이다. 이러한 방법의 Fe-단백질의 기능은 Mofe-단백질과 상호작용을 위해 적합한 구조를 갖추며 전자 전달을 위한 추진력을 제공하기 위해 산화 환원 퍼텐셜을 변화시키는 능력에 의존한다. Nitrogenase Fe-단백질에 MgADP가 결합한 (혹은 떨어진) 구조적 정보는 핵산 결합 자리로부터 MoFe-단백질과의 결합력을 조절하기 위한 장거리 상호작용 메커니즘을 제시한다. 스위치 I과 II의 두 가지 경로가 뉴클레오티드의 신호전달 메커니즘을 담당한다. MgADP가 결합된 Fe-단백질의 구조는 Fe 단백질이 핵산과 결합할 때 관찰되는 [4Fe-4S] 클라스터의 생물리학적 특성 변화의 기초를 제공한다. 스위치, I과 II의 핵산 의존 신호전달 경로에서 특정 아미노산이 치환된 nitrogenase Fe-단백질의 구조들이 X-선 회절법에 의해서 결정되었다. 이들 경로는 아미노산 치환 연구, 구조 분석, 유사한 핵산 의존 신호전달 경로에 이용된 다른 단백질 등에 의해서도 분석되었다. 이들 경로가 거대분자 착물 형성과 분자간 전자 전달을 위한 MgADP 결합과 가수분해의 신호전달 경로로의 타당성이 조사되었다. 이러한 결과는 nitrogenase Fe 단백질과 MoFe-단백질 착물에서 Fe-단백질의 변이와 상호작용의 생물리학적 및 생화학적 특성을 위한 기초적 자료를 제공할 것이다.

• 헤리티지:역사와 과학
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• 제52권2호
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• pp.122-141
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• 2019

고려궁성은 개성에 위치하고 있다는 유적의 특수성으로 인해 유물에 대한 단편적인 접근만이 가능하였으나, 본고에서는 고려궁성 내 전각군의 배치와 역사 기록들에 대한 이해를 바탕으로 출토 자기들을 해석해보았다. 그중 명문 기호 자기는 유적에 대한 보다 구체적인 정보들을 제공하므로 해당 건물지의 시기와 성격, 궁궐의 운영 등을 종합적으로 추정해볼 수 있다. 8차에 걸쳐 진행된 고려궁성의 발굴조사에서 출토된 자기들의 전반적인 양상을 살펴보았으며, 고려궁성에서 출토된 18종의 명문 기호 청자들을 특징 시기별로 분류하였다. 본고에서는 13세기 후반으로 편년되었던 '소전(燒錢)'명 청자들을 고려궁성 발굴조사 결과와 문헌 기록에 근거하여 13세기 전반에 사용되었던 것으로 보았다. 이는 '소전'명 청자와 공반하는 기호(${\circ}$, ${\odot}$) 청자, '성(成)'명 청자의 편년, 그리고 이들 청자가 중앙건축군의 선경전(宣慶殿, 회경전) 뒤편에서 출토되었다는 점을 종합적으로 검토한 결과이다. 13세기 후반에는 초제가 서부건축군의 강안전(康安殿, 대관전)에서 대부분 행해졌고, '소전'명 청자가 출토된 선경전 구역에서 초제가 거행된 것은 강화 천도(1232~1270) 직전인 13세기 전반에 집중되어 있기 때문이다. 따라서 8차 발굴조사에서 출토된 '소전'명 청자 잔을 비롯한 다수의 잔과 잔탁은 13세기 전반 선경전에서 거행된 초제에서 사용되었을 가능성이 크다.

• Archives of Reconstructive Microsurgery
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• 제6권1호
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• pp.73-79
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• 1997

Complete denervation after severe brachial plexus injury make significant muscle atrophy with loss of proper function. It is much helpful to reconstruct the essential function of the elbow flexion movement in patient with total loss of elbow flexion motion after brachial plexus lesion which was not recovered with nerve surgery or long term conservative treatment from onset. In whole arm type brachial plexus injury, if there were no response to neurotization or neglected from injury, the volume of the denervated muscle is significantely reduced month by month. About 18 months most of the muscle fibers change to fibrous tissues and markedly atrophied irreversibly, further waiting is no more meaningful from that period. Authors performed 14 cases of functioning gracilis muscle transfer from 1981 to 1995 with microneurovascular technique, neuromusculocutaneous free flaps were performed for reconstruction of lost elbow flexion function. Average follow-up period was 5 years and 6 months. We used couple of intercostal nerves as a recipient nerve which were anastomosed to muscular nerve from obturator nerve in all cases. Recipient vessels were three deep brachial artery and eleven brachial artery which were anastomosed to medial femoral circumflex artery with end to end or end to side fashion. Average resting length of the transplanted gracilis were 24 cm. We can get average 54 degree flexion range of elbow with fair muscle power from flail elbow. There were one case of muscle necrosis with lately developed thrombosis of microvascular anastomosed site which comes from insufficient recipient arterial condition, 3 cases of partial marginal necrosis of distal skin of the transplanted part which were not significant problem with spontaneously solved with time goes by gracilis muscle has constant neurovascular pattern with relatively easy harvesting donor with minimal donor morbidity. Especially it has similar length and shape with biceps brachii muscle of upper arm and longer nerve pedicle which can neurorrhaphy with intercostal nerve without nerve graft if sufficient mobilization of the nerves from both sides of gracilis and intercostal region. Authors can propose gracilis muscle transplantation with intercostal nerves neurotization is helpful method with minimal donor morbidity for neglected brachial plexus palsy patients.