• 인터넷정보학회논문지
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• 제13권4호
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• pp.95-102
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• 2012

차량 애드 혹 네트워크(VANETs)를 위한 응용들의 개발은 지능적 안전 운송시스템 제공이라는 매우 제한적인 명확한 목표를 가지고 있다. 공공의 안전을 위한 긴급경고 기술은 제한된 시간에 신속하고 효율적으로 경고 메세지를 전달하는 지능형 방송 기법을 필요로 하는 응용중의 하나이다. VANETs 방송 프로토콜 설계 시에 접근제어 계층에서 여러 노드들이 동시에 전송을 시도할 경우, 다수 패킷들의 충돌과 여분의 지연을 발생하는 방송폭풍 문제가 고려되어야 한다. 본 논문에서는, 효율적으로 방송폭풍 문제와 시간 한계를 해결할 수 있는 조기 지능형 경보 방송(EI-CAST) 알고리즘을 제안한다. 제안 알고리즘은 충돌시간(TTC)에 기초한 조기경보 기술과 퍼지논리에 기초한 지능형 방송 기술을 사용하며, 시뮬레이션을 통해 제안 알고리즘과 기존 경보방송 알고리즘의 성능을 비교 평가 하였다. 실험결과 제안 알고리즘의 경우 경보 전송거리 4 km 이내의 차량들은 사고발생 이전에 경보메시지를 수신할 수 있으며 패킷 충돌이 없음을 확인할 수 있었다.

• 정보보호학회논문지
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• 제20권4호
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• pp.145-154
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• 2010

종단간 암호화는 계좌 비밀번호 및 계좌번호 등 주요 금융거래정보를 암호화하여 이용자 PC에서부터 전자금융거래 서버까지 보호하는 것을 의미한다. 초기에 적용된 종단간 암호화는 이용자 PC내에 평문으로 존재하는 구간이 없어야 한다는 기본적인 보안요구사항을 만족하지 못하여 전자금융거래 시 여러 해킹기법에 의해 취약함이 발견되었다. 따라서 확장 종단간 암호화 기술은 이용자의 금융거래정보에 대해 기밀성 및 무결성을 제공하여 유출, 위 변조 등의 위협으로부터 보호하고 있다. 본 논문에서 확장 종단간 암호화 기술에 대해 살펴보고 금융회사에서 확장 종단간 암호화 기술 적용 시 고려해야 할 보안 고려사항에 대해 알아본다.

• Physical Therapy Rehabilitation Science
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• 제12권1호
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• pp.43-47
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• 2023

Objective: To present a case study of a 69-year-old woman with COVID-19 who developed neurological complications due to Extracorporeal Membrane Oxygenation (ECMO) therapy and highlight the importance of daily neurological examinations and rehabilitation in the early detection and management of ECMO-related neurological complications in an isolation ICU. Design: A case report Methods: The patient received ECMO therapy, followed by neurological monitoring and rehabilitation in an isolation ICU. Daily neurological examinations were conducted to monitor the patient's neurological symptoms. Computed tomography was performed to confirm the presence of a hematoma in the left hamstring, which was identified as the cause of the neurological complication. Ultrasound-guided aspiration was immediately performed, and sciatic neuropathy predominantly involving the peroneal division was identified after aspiration. Results: Successful recovery was made possible by the early detection of neurological complications and rehabilitation in an isolation ICU. Although electrodiagnostic tests were not performed due to limited access to the isolation ICU, the appropriate intervention time could be determined through daily neurological examinations and rehabilitation, thereby minimizing neurological sequelae. Conclusions: ECMO-related neurological complications are well known, and their recognition in the ICU can be challenging. The presented case highlights the importance of daily neurological examinations and rehabilitation in the early detection and management of ECMO-related neurological complications in an isolation ICU, which can minimize neurological sequelae.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제27권4호
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• pp.246-257
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• 2024

Purpose: Administering early parenteral amino acids to very low birth weight (VLBW) premature infants (birth body weight [BBW]<1,500 g) is challenging due to factors such as holidays, cost, and access to sterile compounding facilities. Using advance-prepared parenteral nutrition (PN) may address this issue and should be evaluated for its safety and potential benefits. Methods: We extracted data from medical records collected between July 2015 and August 2019. VLBW infants received PN for at least seven days and were split into two groups: the traditional group (n=30), which initially received a glucose solution and then PN on workdays, and the pre-preparation group (n=16), which received advance-prepared PN immediately upon admission to the neonatal intensive care unit. Results: The median BBWs of the traditional and pre-preparation groups were 1,180.0 vs. 1,210.0 g. In the initial two days, the pre-preparation group had a significantly higher amino acid intake (2.23 and 2.24 g/kg/d) than the traditional group (0 and 1.78 g/kg/d). The pre-preparation group exhibited greater head circumference growth ratio relative to birth (7th day: 1.21% vs. -3.57%, p=0.014; 21st day: 7.71% vs. 3.31%, p=0.017). No significant differences in metabolic tolerance were observed. Conclusion: Advanced preparation of PN can be safely implemented in VLBW preterm infants, offering advantages such as early, higher amino acid intake and improved head circumference growth within the first 21 days post-birth. This strategy may serve as a viable alternative in settings where immediate provision of sterile compounding facilities is challenging.

• 한국자동차공학회논문집
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• 제11권6호
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• pp.7-13
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• 2003

The purpose of this study is to investigate the effect of the in-cylinder flows and different injection timings on fuel behavior in the cylinder of a GDI engine. Three different flows types induced by using masked port, unmasked port, and port deactivation were tumble, swirl&tumble, and high swirl respectively. LIEF technique was applied to investigate the mixture formation and fuel distribution at ignition time in the transparent engine with optical access through the piston top and upper part of cylinder liner. Injection timings of 180,90, and 60 degrees before TDC were examined. It was found that tumble flow was more effective on the homogeneous mixture formation than other flow and swirl flow transported more fuel vapor to the exhaust side at early injection mode, and swirl and swirl & tumble flow made fuel vapor concentrate around the cylinder center at late injection mode.

• Archives of Plastic Surgery
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• 제47권5호
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• pp.483-486
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• 2020

Midline clefts of the upper lip are rare, and it is therefore important that surgeons have access to a methodical approach for when these presentations are encountered. We adapted principles of the anatomic subunit approximation for unilateral cleft lip, to the repair of midline clefts. The overt use of anatomic landmarks to define the repair results in a design that inherently adjusts to varying degrees of clefts and can accommodate asymmetries. The "measure twice, cut once" style is an advantage to new surgeons and to surgeons who seldom encounter this presentation. We describe the details of surgical repair in the context of a patient with Pai syndrome and associated nasal hamartomas that resulted in nasolabial asymmetry. This is the first report of surgical outcome following treatment of Pai syndrome and includes early and 5-year follow-up. The system of repair that we describe is applicable to both symmetric and asymmetric midline clefts.

• 노동경제논집
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• 제38권2호
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• pp.25-58
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• 2015

본 연구에서는 소득과 소비의 불평등을 비교하고, 소득과 소비의 상호 연계에 있어서 항상소득가설의 역할을 분석하였다. 1990년 이후 소득 불평등도는 계속 심화되는 추세를 보였으나, 소비의 불평등도는 2000년대 초반까지 오히려 완화되다가 이후 소득의 불평등도와 동행하는 양상을 보이고 있다. 이는 2000년대 초반 이후 소비에 대한 제약이 충분히 완화되어 우리나라 가구의 소비가 항상소득에 의해 결정되는 양상이 정착되고 있음을 반영하는 것으로 판단된다. 결과적으로 2003년 이후 소비와 소득의 불평등도가 동행하는 양상은 소득의 불평등도 변화에 있어서 항상적 요인의 불평등도가 변동하고 있음을 의미하는 것으로 평가된다.

• 천문학회보
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• 제39권2호
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• pp.56.1-56.1
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• 2014

Although the growth of structure, as traced by galaxy clusters, has been extensively studied through cosmological simulations and large-scale surveys, the early formation and evolution of their galaxy content, and its relation to the transformation of the host environment, are still somewhat poorly understood. This is particularly true of the processes that give rise to the quiescent galaxy population between z=3 and z=2. Recent discoveries at z~2 are now bridging the gap between the well-established massive clusters of the last 9 Gyr and the high-redshift universe, and new datasets are now giving us access to statistical populations of intermediate-mass structures at this epoch. I will discuss the properties of quiescent galaxies in the most distant confirmed X-ray detected galaxy clusters, their implications for galaxy quenching at high-redshift as well as the regulation of star formation at group scales at z~2.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.1266-1269
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• 2003

Many studies have indicated that most of a product's cost is fixed early in its lift cycle, before the original design cycle is complete. This implies that we should consider various aspects of product lift cycle at the design stage. This means the need of collaboration in design stage. Because the Internet provides instant access to a wealth of design information, the Internet is used by the collaborative design team members as a medium to share data, information and knowledge, and in some cases for product data management and project management by integrating the Web with appropriate technologies. This paper presents a real-time collaborative design system for powerful interaction performance, based on the Internet and Web technologies. Using The system use the client/server architecture and the purpose of the system is to provide a method that enables real-time view, review and modification of the 3D model through the Internet.

• 대한인간공학회지
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• 제11권1호
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• pp.67-79
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• 1992

Cardiac systolic time intervals (STLs) and Heather index (HI) were used to access changes in left ventricular function of six male subjects exposed to postural changes,$0^{\circ}C$, ${\pm}2^{\circ}C$, ${\pm}45^{\circ}C$, ${\pm}90^{\circ}C$, Significant prolongation of the pre-ejection period (PEP) and PEP/ LVET ratio, shortening of the left ventricular ejection time (LVET), STI, HI and $1/PEP^{2}$were observed during exposure to both $+45^{\circ}C $ and $+90^{\circ}C $But the values measured during $-45^{\circ}C $ and$-90^{\circ}C $ were reversed. Changes in fluid shift, filling volume, preload, after load and sympathetic activities may account for the observed findings. Early response of cardiac foctions was recorded using impedance cardiography. This method is very simple but accurate. Thus it will be useful in this aerospace and work physiology. In conclusion, STIs appear to provide reliable noninvasive method for examining changes of cardiac function during exposure to postural changes.