• 한국데이터정보과학회:학술대회논문집
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• 한국데이터정보과학회 2004년도 추계학술대회
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• pp.25-32
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• 2004

In this study, we use various change-point detection methods to detects Korea economic crisis of 1997, and then compares their performance. In change-point detection method, there are three major categories: (1) the parametric approach, (2) the nonparametric approach, and (3) the model-based approach. Through the application to Korea foreign exchange rate during her economic crisis, we compare the employed change-point detection methods and, furthermore, determine which of them performs better.

• Journal of the Korean Data and Information Science Society
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• 제15권3호
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• pp.585-592
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• 2004

This study detects Korea economic crisis of 1997 using various change-point detection methods and then compares their performance. In change-point detection method, there are three major categories: (1) the parametric approach, (2) the nonparametric approach, and (3) the model-based approach. Through the application to Korea foreign exchange rate during her economic crisis, we compare the employed change-point detection methods and, furthermore, determine which of them performs better.

• Archives of Reconstructive Microsurgery
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• 제17권1호
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• pp.19-27
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• 2008

Purpose: Microvascular reconstructive surgery has become an integral part of the treatment of head and neck cancer patients. This review of 121 free flaps for head and neck cancer patients performed over the last 11 years was done to evaluate circulatory crisis, salvage, and secondary reconstruction and to investigate which factors may contribute to these rates. Method: Nine emergent explorations among 121 head and neck reconstruction with free flaps were reviewed to analyze detection of vascular crisis, the time interval from detection of circulatory crisis to exploration, operation procedures and results, and secondary reconstructions. Emergent exploration was done with our protocol. Result: Nine free flaps exhibited signs of vascular problems between 1 day and 6 days postoperatively. The emergent exploration rate of this series was 7.4% (9/121). The salvage rate was 55.6% (5/9), giving an overall flap viability of 96.7% (117/121). In our study, preoperative radiation therapy, positive smoking history, alcohol consumption history, combined disease such as diabetes mellitus and hypertension, recipient vessels and types of vascular anastomosis were not related to the causes of circulatory crisis. The mean time interval between the onset of clinical recognition of impaired flap perfusion and re-exploration of the salvaged 5 flaps was 3.2 hours, that of failed 4 flaps was 11.25 hours. Conclusion: Despite high overall success rate, relatively low salvage rate may be attributed to late detection of circulatory crisis and in long time interval between detection and exploration. We conclude that early detection of circulatory crisis and expeditious re-exploration are a matter of great importance for the success of salvage operation.

• 한국병원경영학회지
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• 제22권3호
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• pp.144-156
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• 2017

Purpose: Crisis is inevitable to every organization and therefore, successful crisis management is critical to the organizations' survival and prosperity. With the understanding, this study aims to draw propositions for successful crisis management of hospitals when facing infectious disease outbreak. For the purpose, a case of a small and medium sized hospital's experience of crisis management during 2015 Middle East Respiratory Syndrome outbreak was analyzed. Methodology/Approach: The detailed internal circumstances and experiences of the hospital during the MERS outbreak were identified by in-depth interview as well as the extensive material review, and analyzed under the view of the theories of accident, error, and crisis in relation of organization management Findings: Overall, nine propositions are drawn by the phase of crisis. In pre-crisis phase, for example, 'the hospital preparedness has positive influence on the effective responding to the crisis'. In detection phase, 'the mindfulness of the hospital organizations' as well as the individuals' has positive influence on detecting the crisis signals'. In crisis phase, for example, 'improvising naturally occurs in crisis by the unknown disease, therefore, a component site supervisor coordinating such improvision is important'. Lastly, in post-crisis phase, 'successful crisis responding experience facilitates the positive hospital culture'. Practical implication: From the experience of a small and medium size hospital, it is suggested that proactive system approach oriented by safety is beneficial for effective crisis management.

• Journal of Information Technology Applications and Management
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• 제23권4호
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• pp.25-39
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• 2016

Asset prices decline sharply and stock markets collapse when financial crisis happens. Recently we have encountered more frequent financial crises than ever. 1998 currency crisis and 2008 global financial crisis triggered academic researches on early warning systems that aim to detect the symptom of financial crisis in advance. This study proposes a risk recovery index for detection of good opportunities from financial market instability. We use SVM classifier algorithms to separate recovery period from unstable financial market data. Input variables are KOSPI index and V-KOSPI200 index. Our SVM algorithms show highly accurate forecasting results on testing data as well as training data. Risk recovery index is derived from our SVM-trained outputs. We develop a trading system that utilizes the suggested risk recovery index. The trading result records very high profit, that is, its annual return runs to 121%.

• 한국정보전자통신기술학회논문지
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• 제14권2호
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• pp.128-133
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• 2021

현재 자율주행차량 시장은 3레벨 자율주행차량을 상용화하고 있으나, 안정성의 문제로 완전 자율주행 중에도 사고가 발생할 가능성이 있다. 실제로 자율주행차량은 81건의 사고를 기록하고 있다. 3레벨과 다르게 4레벨 이후의 자율주행차량은 긴급상황을 스스로 판단하고 대처해야 하기 때문이다. 따라서 본 논문에서는 CNN을 통하여 차량 외부의 정보를 수집하여 저장하고, 저장된 정보와 차량 센서 데이터를 이용하여 차량이 처한 위기 상황을 0~1 사이의 수치로 출력하는 차량 내·외부 데이터 및 딥러닝 기반 차량 위기 감지 시스템을 제안한다. 차량 위기 감지 시스템은 CNN기반 신경망 모델을 사용하여 주변 차량과 보행자 데이터를 수집하는 차량 외부 상황 수집 모듈과 차량 외부 상황 수집 모듈의 출력과 차량 내부 센서 데이터를 이용하여 차량이 처한 위기 상황을 수치화하는 차량 위기 상황 판단 모듈로 구성된다. 실험 결과, VESCM의 평균 연산 시간은 55ms 였고, R-CNN은 74ms, CNN은 101ms였다. 특히, R-CNN은 보행자수가 적을 때 VESCM과 비슷한 연산 시간을 보이지만, 보행자 수가 많아 질수록 VESCM보다 많은 연산 시간을 소요했다. 평균적으로 VESCM는 R-CNN보다 25.68%, CNN보다 45.54% 더 빠른 연산 시간을 가졌고, 세 모델의 정확도는 모두 80% 이하로 감소하지 않으며 높은 정확도를 보였다.

• Journal of the Korean Data and Information Science Society
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• 제18권2호
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• pp.345-356
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• 2007

This study deals with an early detection problem of structural change in won/dollar exchange market. A CUSUM algorithm is developed to monitor relevant economic variables indicating structural change in won/dollar exchange market. We applied the CUSUM algorithm to examine whether or not it was possible to alarm the 1997 economic crisis of Korea in advance.

• International Journal of Advanced Culture Technology
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• 제10권1호
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• pp.294-301
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• 2022

COVID-19 is a crisis with numerous casualties. The World Health Organization (WHO) has declared the use of masks as an essential safety measure during the COVID-19 pandemic. Therefore, whether or not to wear a mask is an important issue when entering and exiting public places and institutions. However, this makes face recognition a very difficult task because certain parts of the face are hidden. As a result, face identification and identity verification in the access system became difficult. In this paper, we propose a system that can detect masked face using transfer learning of Yolov5s and recognize the user using transfer learning of Facenet. Transfer learning preforms by changing the learning rate, epoch, and batch size, their results are evaluated, and the best model is selected as representative model. It has been confirmed that the proposed model is good at detecting masked face and masked face recognition.

• 한국컴퓨터정보학회논문지
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• 제8권3호
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• pp.179-187
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• 2003

이 논문에서는 정보보안 분야의 각종의 위험신호(risk signal)에 대해 조직이 왜 적절한 대응을 하지 못하는 가를 조직의 구조적 측면에서 그 원인을 분석하고자 하였다. 위기는 갑자기 오지 않으며, 많은 경우 위기는 위기와 관련한 위험신호(risk signal)를 제기하면서 진전된다. 이러한 위험신호에 대해 적절하게 대응하는 경우, 위험은 새로운 기회를 만들어내게 되지만 그러하지 않은 경우 위험은 경제적, 비경제적인 측면에서 재난적인 결과를 초래할 가능성을 갖는다. 이 논문에서는 인과지도(causal diagram)을 이용하여 시스템적인 관점에서 환류하는 인과 고리의 관점에서 현상을 분석하는 시스템 다이나믹스적인 분석을 시도하였다. 분석결과, 조직의 성장과 업적 위주의 분위기가 일종의 압력이 되어, 안전에 대한 불감을 강화하게 되며, 이는 각종의 위험신호들에 내재된 위험성에 대해 과소평가하는 압력으로 작용하게 되는 점을 분석하였다. 이는 나아가서 기술적 기반에 대해 적절한 투자가 이루어지 못하게 하고, 정보보안과 관련한 학습을 적절하게 하지 못하도록 한 것으로 나타난다. 이 논문은 탐색적으로 정보보안 분야에서의 위험신호와 조직학습과의 관계를 분석한 탐색적 연구로서의 성격을 가진다.

• Clinical and Experimental Vaccine Research
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• 제12권1호
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• pp.77-79
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• 2023

The Philippines is still in a tight battle with the coronavirus disease 2019 pandemic since many cases are detected daily. With the continuous spread of another disease worldwide-monkeypox, many Filipinos are alarmed if the country's healthcare system is prepared enough, especially with the detection of its first case. Learning from the unfortunate experiences of the country during the current pandemic is essential in facing another health crisis. With this, recommendations for a robust healthcare system are proposed centered on: a massive digital information campaign about the disease; training healthcare workers to raise awareness about the virus and its transmission, management, and treatment; an intensified surveillance and detection procedure to monitor cases and execute contact tracing properly; and a persistent procurement of vaccines and drugs for treatment, with a well-designed vaccination program.