• 융합보안논문지
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• 제19권5호
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• pp.19-24
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• 2019

MANET은 이동 노드로만 구성되어 있기 때문에 기존의 유선 환경에서의 라우팅 프로토콜을 그대로 적용할 수 없다. 따라서 이러한 특성이 고려된 라우팅 프로토콜이 필요하다. 특히 라우팅 단계에서 악의적인 노드들을 배제하지 못한다면 네트워크 성능은 크게 떨어질 수 밖에 없다. 본 논문에서는 라우팅 성능을 향상시키기 위해 영역기반 침입탐지 기법을 제안하였다. 제안한 기법에서는 전체 네트워크를 일정한 영역으로 분할한 후 영역관리 노드를 이용하여 영역내 공격 탐지가 이루어지도록 하였으며, 멤버 노드로부터 수신한 완료 메시지를 이용하여 서로간 협업을 통해 경로상에 존재하는 공격 노드를 탐지할 수 있는 방법을 제안하였다. 그리고 탐지한 공격노드 정보를 블록체인에 저장하여 공유함으로써 네트워크에 참여하는 모든 노드들이 공격노드 정보를 공유할 수 있도록 하는 방법을 적용하였다. 제안한 기법의 성능 평가는 기존의 보안 라우팅 기법들과 비교 실험하였으며, 실험을 통해 제안한 기법의 우수한 성능을 확인할 수 있었다.

• 대한소아치과학회지
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• 제36권3호
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• pp.475-480
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• 2009

저위교합이란 치아가 출은한 이후 유착 등의 원인으로 맹출이 정지되어 주위 인접치 보다 교합평면이 낮아지는 것을 말한다. 저위교합은 인접치들의 경사, 저위교합된 부위의 공간상실, 대합치의 정출, 해당부위 치아우식 감수성의 증가, 후속 영구치의 맹출경로 변위, 매복, 회전 등의 문제점을 유발할 수 있으므로 조기 진단 및 정기검진을 통한 적절한 치료가 필요하다. 저위교합된 유구치는 대부분 영구 계승치가 존재하며 일반적으로 정상 탈락한다. 그러나 저위교합된 유구치의 탈락이 지연되고 저위교합의 정도가 심화되어 해당부위의 공간상실이 발생하면, 공간부족으로 인하여 후속 영구치의 매복을 야기할 수 있다. 이러한 경우 교정적으로 공간확장술을 시행한 후 외과적 발치를 고려해야 한다. 본 증례는 하악 제 2유구치의 저위교합이 관찰된 3명의 환아를 대상으로 공간에 대한 평가 후 필요한 경우 공간확장술을 시행하고 발치를 시행함으로써 저위교합으로 인해 발생된 문제점을 개선하고, 추후에 발생될 합병증을 예방하였기에 이를 보고하는 바이다.

• 한국콘텐츠학회논문지
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• 제12권5호
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• pp.525-540
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• 2012

본 연구에서는 사이버대학에서 고립감, 상호작용, 콘텐츠만족도, 성취도 및 학습지속의향 간의 구조적 관계를 검증하고 직장유무에 따른 차이를 분석하는 것을 목적으로 하였다. 이를 위해 2011년 2학기 A 사이버대학 학생을 대상으로 연구를 수행하였다. 연구결과 첫째, 상호작용은 고립감에 영향을 미치는 것으로 나타났다. 둘째, 상호작용은 콘텐츠만족도에 유의한 영향을 미치는 것으로 나타났으며 셋째, 상호작용이 성취도에 미치는 영향력이 유의한 것으로 나타났다. 넷째로 고립감과 상호작용은 학습지속의향에 영향을 미치는 것으로 나타났다. 마지막으로 직장 유무에 따른 고립감, 상호작용, 콘텐츠만족도, 성취도 및 학습지속의향에서 경로계수 차이를 분석한 결과 집단 간 유의미한 차이는 없는 것으로 드러났다. 이러한 결과를 바탕으로 사이버대학에서의 사이버교육콘텐츠 및 교육의 질 제고를 위해 요구되는 콘텐츠 설계 및 운영전략을 제언하였다.

• Asia pacific journal of information systems
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• 제5권2호
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• pp.79-100
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• 1995

Internal Control(IC) comprises the plan of organization and all of the coordinating methods and measures adopted in a business to safeguard its assets, check the accuracy and reliability of its accounting data, promote operational efficiency and encourage adherence to the prescribed managerial policies. If an organization's IC is not adequate, Accounting Information System (AIS) will be vulnerable to accomplish the organizations successes. Therefore, an effective and efficient IC is essential to its successes. The purpose of this study is to analyze the impact of EDP IC on the perceived usefulness of AIS. Do the general controls indirectively affect to the usefulness of AIS through th application controls? To solve these problems, a research model and a set of hypotheses were established and empirically tested. 60 financial institutions (banks, insurance companies, security companies) agreed to participate in the study. Data were gathered through structured interviews with 60 information systems managers and 537 users of accounting information of each company. Survey forms were designed and collected from financial institutions in Seoul. Information systems' managers of financial institutions responded to questionnaire(1) which consists of a series of 70 questions related to practice and perceived importance. Questionnaire (2) was received from 537 users, who responded to series of 17 questions related to the perceived usefulness. The results of analysis are summarized below. Effects of general controls are more direct on AIS's usefulness than those of application controls. Whereas, indirect effects of application controls are geater than those of general controls. Therefore, the greater the effects of application controls on general controls, the higher the perceived usefulness of AIS. In conclusion, this study supports that the perceived usefulness of AIS is affected by IC which are composed of general controls and application controls. The results of this study has significant implication to financial institution as computer fraud potential increases. Because of global competitions, financial institutions should restructure to IC and AIS in order to take advantage of the technological progress in Information System.

• Architectural research
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• 제13권3호
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• pp.31-40
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• 2011

Profit-keeping behaviors naturally occur in the market to satisfy consumers, and the logic behind it lies in the economies of scale. On the flip side, some commodities transacted in the market are not available or can not be easily acquired unless the demand is high enough. Under this proposition, some consumers rise and find their own solution to meet the services at a reasonable cost or at an adequate level. The commonly adopted way is to establish a cooperative, and it stirs purchasing power by pooling resources and further bargains price and service quality. As a consumer cooperative, housing cooperatives notably found in rural towns enable the elderly to continue independent living. This study is to take a closer look at residential life of the rural elderly in housing cooperatives. Utilizing in-depth focus group interviews with 40 residents in four housing cooperatives, this qualitative research draws main factors affecting the decision to move in, residential assessment, and strengths and weakness of living in a housing cooperative. The primary factor influencing the moving decision is to continue to independent living in a familiar community, and the bottom line is planning ahead. Frailty and bereavement are found to be the leading occasions for them to move. The participants are satisfied with the independent living arrangement, and particularly, cited such features as safety and security, elderly-friendly design, common spaces, freedom, social activities and efficient living. Also, it is stated that some cooperative natures such as control over the property and giving a voice on management render positive impacts on the satisfaction with communal living. In spite of all the benefits and strengths, participants face with a public notion that an independent living arrangement like a housing cooperative has never done before in rural towns, so that most people recognize it as part of dependent living arrangements like nursing home.

• 복식문화연구
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• 제22권4호
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• pp.619-631
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• 2014

This study proposes an educational direction to be followed by the clothing departments of Korea's specialized high schools in order to help achieve high levels of job placements and to strengthen their students' competitiveness. A comparison was made of the curricula in Korea's specialized high schools and in several fashion schools in other countries including the United States, Italy, France, Taiwan, and Japan. To this end, publicly available educational records were retrieved from domestic school documentation, vocational high school portals, and domestic/overseas school web sites, and were then reviewed. The archival data extracted from these sources shows that the curricula of the three chosen domestic schools uniformly focus on foundational courses such as general computer skills, general design, accounting principles, design principles, and drawing, as well as practical courses such as the design of western clothing, fashion design, fashion CAD, management of clothing material, design of Korean clothing, and knitting. Unlike these standardized courses, it was found that overseas fashion schools provide a more technically-advanced and design-focused education based on the interests of the individual student. Moreover, their education system nurtures the students' creativity through adequate field experience and history/language education. The findings of this study suggest that Korean specialized high schools should find a way to accommodate their students' interests and to provide them with personalized fashion education by adopting a more flexible curriculum. An educational line that considers the individual student's aptitudes and career path will help foster creativity and novel ideas, which, in turn, will contribute to the development of the fashion industry.

• 대한전자공학회논문지TC
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• 제45권3호
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• pp.61-67
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• 2008

Proxy MIPv6(PMIPv6)는 이동 노드를 대신하여 액세스 망에서 노드의 이동성을 지원하기 위한 네트워크-기반 이동성 관리 프로토콜이다. 기존의 PMIPv6 프로토콜에서는 이동 노드가 통신하고자 하는 상대 노드가 동일한 PMIPv6 도메인에 있는 또 다른 이동 노드인 경우에는, 두 이동 노드간에는 최적화되지 않은 경로를 따라서 패킷이 교환되는 문제가 발생한다. 이를 해결하기 위하여 PMIPv6 기반 망에서의 경로 최적화 기법이 제안되었다. 그렇지만, 이 기법에서는 송신측에서 전송한 패킷이 순서에 어긋나게 수신측에 도착하여 응용 계층에서의 성능 저하 문제가 발생한다. 이 논문에서는 PMIPv6 프로토콜에서 패킷의 순서 어긋남 문제를 해결할 수 있는 flush 기반의 경로 최적화 메커니즘을 제안한다. 제안된 메커니즘의 성능을 모의실험을 통하여 분석하였으며, 제안된 방법이 기존의 PMIPv6 기반의 경로 최적화보다 우수한 성능을 제공함을 알 수 있었다.

• 디지털융복합연구
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• 제18권5호
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• pp.105-114
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• 2020

본 연구는 OTT 서비스 이용자들을 대상으로 유료지불의사에 영향을 미치는 요인을 탐색하였으며, 주요 결과는 다음과 같다. 첫째, OTT 서비스 이용자들의 지각된 유용성은 이용만족에 정적 영향을 미치는 것으로 나타났다. 둘째, OTT 서비스 이용자들의 지각된 유희성은 이용만족에 정적 영향을 미치는 것으로 나타났다. 셋째, OTT 서비스 이용자들의 지각된 비용은 이용만족에 정적 영향을 미치는 것으로 나타났다. 넷째, OTT 서비스 이용자들의 지각된 유용성은 유료지불의사에 정적 영향을 미치는 것으로 나타났다. 다섯째, OTT 서비스에 대한 이용만족은 유료지불의사에 정적 영향을 미치는 것으로 나타났다. 결론적으로 OTT 서비스 이용자들의 지각된 유용성, 지각된 유희성, 지각된 비용은 이용만족을 높이며, 지각된 유용성과 이용만족은 유료지불의사를 예측하는 핵심요인이라는 사실을 확인하였다. 본 연구는 OTT 서비스 이용자들의 유료지불의사를 예측하고 설명할 수 있는 경로를 밝혔다는 점에서 의의가 있을 것이다.

• 대한인간공학회지
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• 제31권6호
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• pp.725-731
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• 2012

Objective: The aim of this study is to investigate visual feedback effects and human performance in the foot mouse control. Background: Generally, computer mouse tasks are controlled by visual feedback. In order to understand the characteristics of a foot mouse control, it is important to investigate the patterns of visual feedback involved in foot-mouse control tasks. Human performance of foot mouse control is also an important factor to understand the foot mouse control. Method: Three types of mouse control were determined to investigate visual feedback effects and human performance in the foot mouse control. Visual feedback effects in the foot mouse control were compared with those of a typical hand mouse. The cursor movement speed and mental workload were measured in the three types of tasks and two types of mouses. Results: Mouse control tasks with an element of homing-in to the target were more quickly performed by the hand mouse than the foot mouse. Mental workload was also higher in the foot mouse than the hand mouse. However, in the steering movement, human performance of the foot mouse control was not lower than that of the hand mouse control. Visual feedback in the foot mouse control was less required than in the hand mouse control. Conclusion: The foot mouse was not efficient in the most mouse control tasks, compared to the hand mouse. However, the foot mouse was efficient in the steering movement, moving a cursor within a path with lateral constraints. Application: The results of this study might help to develop the foot mouse.

• 마이크로전자및패키징학회지
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• 제12권4호통권37호
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• pp.331-338
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• 2005

The rapid advances in high power light sources and arrays as encountered in incandescent lamps have induced dramatic increases in die heat flux and power consumption at all levels of high power LED packaging. The lifetime of such devices and device arrays is determined by their temperature and thermal transients controlled by the powering and cooling, because they are usually operated under rough environmental conditions. The reliability of packaged electronics strongly depends on the die attach quality, because any void or a small delamination may cause instant temperature increase in the die, leading sooner or later to failure in the operation. Die attach materials have a key role in the thermal management of high power LED packages by providing the low thermal resistance between the heat generating LED chips and the heat dissipating heat slug. In this paper, thermal transient characteristics of die attach in high power LED package have been studied based on the thermal transient analysis using the evaluation of the structure function of the heat flow path. With high power LED packages fabricated by die attach materials such as Ag paste, solder paste and Au/Sn eutectic bonding, we have demonstrated characteristics such as cross-section analysis, shear test and visual inspection after shear test of die attach and how to detect die attach failures and to measure thermal resistance values of die attach in high power LED package. From the structure function oi the thermal transient characteristics, we could know the result that die attach quality of Au/Sn eutectic bonding presented the thermal resistance of about 3.5K/W. It was much better than those of Ag paste and solder paste presented the thermal resistance of about 11.5${\~}$14.2K/W and 4.4${\~}$4.6K/W, respectively.