• Archives of Plastic Surgery
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• 제36권5호
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• pp.555-558
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• 2009

Purpose: The high success rate of free flap transfers is well documented in previous literature, and is possible due to the early detection of vascular compromise and timely reoperation. We specifically analyzed the operative results of immediate and delayed reconstruction with free transverse rectus abdominis musculocutaneous(TRAM) flap respectively in order to reveal its distinctive features on timing and causes of vascular compromise. Methods: The senior author operated on 158 patients, 161 cases of free TRAM flap for breast reconstruction. 51 patients underwent delayed reconstruction, whilst immediate reconstruction was performed in the other 107 patients. All patients were monitored every 3 hours for the first 3 days. We reviewed medical records of all patients, and tested statistical significance with the Fisher's test. Results: Reoperation was performed in 20 cases, but the cases include hematoma with bleeding focus and arterial anastomosis site rupture due to abrupt arm abduction. We performed reoperation in 15 cases of suspicious vascular compromise. Flap compromise was noticed mostly within 24 hours, but not longer than 72 hours. Venous compromise was dominant by 11 cases (73.3%). There was difference in the timing of flap compromise between immediate and delayed reconstruction. All the cases of delayed reconstruction did not show signs of vascular compromise after 12 hours postoperatively. On the other hand, cases of vascular compromise were observed until 72 hours postoperatively in cases of immediate reconstruction. Conclusion: Delayed reconstruction showed vascular compromise within 12 hours postoperatively, while immediate reconstruction showed compromised until the 3rd postoperative day. If more aggressive monitoring is maintained during this period, we believe salvage of flaps may be increased with more efficiency.

• 품질경영학회지
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• 제29권3호
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• pp.49-65
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• 2001

This paper presents new compromise ALT plan which is applied to situations that true relationship between stress and parameters is not known exactly. The assumed failure distribution of this study is one of location-scale family, i. e., exponential, Weibull, and lognormal distributions which have been ones of the popular choices of failure distributions. The method of applying the stress is constant, and the censoring mechanism is Type I censoring. Compared with existing compromise plans under true simple linear model in terms of statistical efficiency, the efficiency of new compromise plan is better than the corresponding other compromise ones in most cases. For case when true model is quadratic, this plan can be used without any severe loss in statistical efficiency. The proposed new compromise ALT plan is illustrated with a numerical example and sensitivity analyses are conducted to study effects of pre-estimates of design parameters.

• 직업교육연구
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• 제37권5호
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• pp.79-100
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• 2018

본 연구는 대학생의 진로타협이 진로관련 변인들과 어떠한 관계가 있는지를 확인하고자 하였다. 이를 위해 대학생 278명을 대상으로 진로타협, 진로결정자기효능감, 진로결과기대, 직업희망, 진로동기, 진로관여행동의 수준을 측정하는 설문을 실시하였다. 자료분석은 SPSS 22.0을 활용하여 신뢰도 분석, 기초 통계 분석, 상관 분석, 회귀 분석을 실시하였고 연구 결과는 다음과 같다. 첫째, 진로결정자기효능감, 진로결과기대 및 직업희망이 높을수록 진로타협 수준은 낮아졌으며, 그 상대적 영향력은 직업희망이 가장 컸다. 또한 진로타협 수준이 높을수록 진로동기와 진로관여행동이 모두 낮아지는 것으로 나타났다. 따라서 우리나라 대학생들의 진로타협은 진로관련 요인들과 부정적인 영향을 주고받고 있음을 확인하였다. 본 연구 결과를 토대로 진로상담자는 진로지도 및 상담 시 대학생들이 진로타협 상황에 효율적으로 대처할 수 있도록 도울 필요가 있다는 점을 밝혔다는 데 의의가 있다.

• International Journal of Aeronautical and Space Sciences
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• 제16권2호
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• pp.137-147
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• 2015

Hypersonic vehicles exhibit distinct dynamic and static characteristics, such as unstable dynamics, strict altitude angle limitation, large control bandwidth, and unconventional system sensitivity. In this study, compromise relations between the dynamic features and static performances for hypersonic vehicles are investigated. A compromise optimal design for hypersonic vehicles is discussed. A parametric model for analyzing the dynamic and static characteristics is established, and then the optimal performance indices are provided according to the different design goals. A compromise optimization method to balance the dynamic and static characteristics is also discussed. The feasibility of this method for hypersonic vehicles is demonstrated.

• 한국시뮬레이션학회논문지
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• 제14권3호
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• pp.43-54
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• 2005

For the effective design of automated distribution center composed of Automated Storage/Retrieval System, Automated Guided Vehicle System, and Conveyor System, we proposed an analysis method to determining. design and control parameters with multiple performance objectives using Compromise Programming, which can resolve the dilemma of conflicting objectives. The Evolution Strategy generates the optimal solutions for each objectives. The Analytic Hierarchy Process selects the best solution among the alternatives generated from Evolution Strategy. The Regression Analysis formulates the objective functions for each objectives. By reducing deviations between goal values and target values generated from Analytic Hierarchy Process, Compromise Programming determines design and control parameters by compromising the multiple objectives formulated using Regression Analysis. When the parameters of system are changed, this proposed analysis method has a benefit of reducing costs and time without repeating whole simulation run.

• 한국콘텐츠학회논문지
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• 제9권10호
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• pp.59-66
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• 2009

강한 지정된 검증자 서명(Strong Designated Verifier Signature Scheme)은 지정된 검증자에게 서명자와 같이 서명을 생성할 수 있는 능력을 줌으로써 주어진 서명이 실제 서명자와 검증자 중에 누가 만든 것인지를 알 수 없도록 하는 서명자의 익명성을 보장하는 특별한 서명 방식으로 소프트웨어 분배 또는 전자 투표 등에서 이용될 수 있다. 본 논문에서는, 강한 지정된 검증자 서명 방식의 중요한 성질인 소스 하이딩(source hiding)과 키 노출 공격 (key-compromise attack)의 관계를 살피고 두 성질을 동시에 만족하는 강한 지정된 검증자 서명을 생성할 수 없음을 보인다. 마지막으로 키 노출 공격에 안전한 ID 기반의 강한 지정된 검증자 서명 기법을 제안한다.

• 산업경영시스템학회지
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• 제21권47호
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• pp.1-10
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• 1998

Testing high reliability devices under nomal operating condition is difficult, because the devices are not likely to fail in the relatively short time available for tests. For most applications it is necessary to accelerate the causes of failure by increasing a stress above its nomal value. Previous accelerated life test(ALT) plans have shown how to find optimum allocation, lowest stress and sample size subject to minimizing the variance of mean life estimator. In these ALT plans, the highest acceptable test-stress was assumed to be specified in advance by the experimenter but there is no guidance for selecting it. This assumption is, however, inappropriate for many applications. Testing devices at too-high stress levels can invalidate the extrapolation model, or introduce failure mechanisms that are not anticipated under nomal operating conditions. In this paper, we propose new 4:2:1 compromise plans using Min-Max method to minimize this risk and present minimized test-stress levels(max, middle, min), and find sample allocation based on Min-Max 4:2:1 compromise plans. In result, we compare previous 4:2:1 compromise plans specified maximum test-stress with Min-Max 4:2:1 compromise plans minimized maximum test-stress.

• 정보보호학회논문지
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• 제30권5호
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• pp.835-846
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• 2020

이메일을 통해서 거래처나 경영진을 사칭하여 금전이나 민감한 정보를 탈취하는 BEC(Business Email Compromise) 공격이 빈번하게 발생하고 있다. 이러한 공격 형태는 최근 발생한 무역사기 중 가장 큰 비중을 차지하며 FBI에서 추정 2019년 피해 금액만 약 17억 달러에 이른다. 하지만 이에 비해서 기업들의 대응 실태를 살펴보면 전통적인 SPAM 차단시스템에 의존하고 있어 보다 치밀해져만 가는 BEC 공격에는 사실상 무방비 상태이며, 임직원에 관련 사고를 안내하고 주의를 당부하는 변화관리 수준의 대응에 머물고 있다. 이에 BEC 사고 유형과 방법들을 분석하고, AI를 통한 기업에서의 효과적인 BEC 공격 대응방안을 제안하고자 한다.

• Journal of Korean Neurosurgical Society
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• 제49권2호
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• pp.128-130
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• 2011

The low lumbar spine is deeply located in flexible segments, and has a physiologic lordosis. Therefore, burst fractures of the low lumbar spine are uncommon injuries. The treatment for such injuries may either be conservative or surgical management according to canal compromise and the neurological status. However, there are no general guidelines or consensus for the treatment of low lumbar burst fractures especially in neurologically intact cases with severe canal compromise. We report a patient with a burst fracture of the fourth lumbar vertebra, who was treated surgically but without fusion because of the neurologically intact status in spite of severe canal compromise of more than 85%. It was possible to preserve motion segments by removal of screws at one year later. We also discuss why bone fusion was not necessary with review of the relevant literature.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.1187-1192
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• 2008

In this paper, a versatile multi-objective optimization concept for fatigue life prediction is introduced. Multi-objective decision making in engineering design refers to obtaining a preferred optimal solution in the context of conflicting design objectives. Compromise decision support problems are used to model engineering decisions involving multiple trade-offs. These methods typically rely on a summation of weighted attributes to accomplish trade-offs among competing objectives. This paper gives an interpretation of the decision parameters as governing both the relative importance of the attributes and the degree of compensation between them. The approach utilizes a response surface model, the compromise decision support problem, which is a multi-objective formulation based on goal programming. Examples illustrate the concepts and demonstrate their applicability.