• 전기학회논문지
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• 제64권7호
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• pp.1081-1087
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• 2015

Recently, the researches of aerial drones are actively executed in various areas, the researches of surface drones and underwater drones are also executed in marine areas. In case of surface drones, they essentially utilize acoustic information by the sonar and consequently have the local information in the obstacle avoidance as the sonar has the limitations due to the beam width and detection range. In order to overcome this, more global method that utilizes optical images by the camera is required. Related to this, the aerial drone with the camera is desirable as the obstacle detection of the surface drone with the camera is impossible in case of the existence of clutters. However, the dynamic-floating aerial drone is not desirable for the long-term operation as its power consumption is high. To solve this problem, a collaborative obstacle avoidance method based on the acoustic information by the sonar of the surface drone and the optical image by the camera of the static-floating aerial drone is proposed. To verify the performance of the proposed method, the collaborative obstacle avoidances of a MSD(Micro Surface Drone) with an OAS(Obstacle Avoidance Sonar) and a BMAD(Balloon-based Micro Aerial Drone) with a camera are executed. The test results show the possibility of real applications and the need for additional studies.

• 한국멀티미디어학회논문지
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• 제16권9호
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• pp.1044-1056
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• 2013

본 논문에서는 피부 색소 침착 영역을 검출하고 침착 정도를 측정하는 알고리즘을 제안한다. 제안한 알고리즘에서는 먼저 훈련 영상(training image)의 통계적 분석을 통해 피부 영역에 대한 GMM-EM 클러스터링 기반 컬러 모델을 구축하고 이를 통해 피부 영역을 추출한 후, 형태학적 처리(morphological processing)를 통해 피부 영역에 존재하는 잡음을 제거한다. 이후 ICA (independent component analysis) 알고리즘을 통해 피부 영역을 헤모글로빈 및 멜라닌 성분으로 분리하고, 각 성분에 대한 투영 변환 블록 계수에 의하여 색소 침착 영역 및 크기를 결정한다. 성능 평가를 위한 모의실험으로부터 제안한 색소 침착 검출 알고리즘은 피부 색소 침착 영역의 크기 및 침착 정도를 정확하게 검출할 수 있음을 확인하였다.

• 대한간호
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• 제29권5호
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• pp.46-53
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• 1991

In the past, management had been done over nurses rather than nursing and this brought the existence of general manager and as a result, nurse-manager's position and role are being threatend. For the up-bringing of nursing to firm professional recognition in the 21st century, it is firmly believed that nursing managers are to be in the position to play the role of general manager with professional qualifications; personal qualities and exact understandings on the role and function of each tier group under her/his management. 124 top(3 nursing superintendents), middle-range(23 supervisors) and unit managers(98 head-nurses) from 3 university hospitals in Seoul were interviewed in order to investigate their belief in the role, professional qualifications, personal qualities as well as the strategy for the development of their leadership qualities. The frame of reference for the interview were developed by the researcher in reference to relevant literatures. It was the common belief that qualifications o[ top-managers and mid-managers require an educational background of master's preparation or higher and clinical career for at least 15 years for top-managers and 5 -10 years for mid-managers. The personal qualities required by nurse managers include; leadership, initiative, judgement, self-confidence, flexibility, open-mindedness and strong motivation. Achievment-orientedness would greatly help them become excellent managers. On the other hand, [or more effective management, managers of each teir group are to fully understand their role and perform "their job responsibilities ie. Top managers are supposed to study with emphasis on organization, function and conceptual s~ill while mid-managers concentrate their effort on the development of skills for direction, guidance and human relationship. Unit managers also supposed to have abilities to manage their function with emphasis on development of clinical performance skill, for direction on operative aspects. The strategies for the development of leadership qualities include program-planning at individual instutional level as well as local, national and international level. Nurse-managers are to be motivated and encouraged to participate in the programs in order to effectively communicate within tier groups.oups.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집A
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• pp.561-566
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• 2001

A long bar impact test to alumina plates(AD 85 and AD 90) was carried out by using fabricated impact testing apparatus. The apparatus adopting a long bar of 2.1m in length made it possible to measure directly the applied impact force to the specimen during bar impact. The dimension of specimens was $33{\times}33mm$ and thickness was 3.4mm. Confinement of D2=18mm outer diameter and D1=10.5mm inner diameter was used to provide contact pressure to the specimen. Contact pressure of p=100 or 200MPa was applied to specimen before impact test. Damage caused in those cases were compared with the case of without contact pressure. The damage of specimen was different depending upon the pressure level of confinement. The existence of confinement had suppressed the development of radial cracks from the bottom of specimen and reduced the extent of damage as compared with cases without contact pressure(p=0MPa). Because the application of contact pressure to the specimen increased the apparent flexural stiffness of specimen during bar impact, it had produced the change of developed damage in the specimen; from the radial cracks to the local contact stress dominant damage. It would contribute to the improvement of the ballistic property in ceramic plates.

• 한국유통학회지:유통연구
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• 제2권2호
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• pp.153-172
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• 1997

The distribution sector is affected by a wide range of regulations. Many of these are related to health and safety, others are related to urban planning and environmental issues, whereas some mainly have an economic basis. But, regulations many be unduly restrictive, in which case they can drive up costs and ultimately prices, or they may, in some cases, reduce consumer choice. Unduly restrictive regulations could also increase costs indirectly, by reducing competition and thus lead to lower productivity growth. In the past few years, distribution sector has gone through drastic changes due to deregulation and market opening. Implementation of regulatory reforms served as an opportunity to change laws and systems which had been an obstacle to development of distribution sector. Market opening of distribution sector became a turning point to promote competition among domestic and foreign firms. However, for small and medium scale of the typical retail enterprises which were in no position to compete in terms of prices, additional facilities, and services, faced a threat of diminished trading area, and even of their existence. Because, large firms may have greater market power than small firms, as they can more easily extract favorable terms when procuring goods, and may also be able to deter entry by advertising outlays or access to the best sites. In addition, larger chain stores armied with sufficient capital dominated trading area and reduced customer's welfare by abusing their monopoly power when competing with other shops, and are often cited as an example of adverse effects of local monopoly. In order to minimize such adverse effects and to foster competition, regulatory reforms in distribution sector should set its goal to promote sound and stable distribution activities through market principle and restoring competition principle, and ultimately to boost customers welfare. Therefore, deregulation in distribution sector should be implemented in a way to promote customers welfare, eliminate entry barriers, and expand competition principle such as productivity and efficiency competition. However, it should be also recognized that deregulation of system alone is not enough to develop the distribution sector. To compete in a increasingly concentrated industry, small enterprises increasingly engage in co-operative arrangements, such as buying groups, strategic alliances or franchise agreements.

• 한국재난정보학회 논문집
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• 제9권4호
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• pp.383-391
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• 2013

본 연구는 기업의 재난 대비활동에 대한 기업의 인식과 현황에 대해 서울과 동경의 기업들을 대상으로, 설문조사하였다. 한국은 일본에 비해 자연재해에 대해 위험도의 인지가 매우 낮았으며, 방재계획 작성, 재해시 직원에 대한 응급지원과 지역사회에 대한 지원의사도 일본에 비해 미미하였다. 다만, 직원의 피난과 귀사계획은 일본보다 더 높은 수준을 기록하였는데, 한국은 민방위 계획에 의거한 소집이 규정되어 있는 데 기인한 것으로 해석된다. 일본의 경우에, 기업의 재해대책과 관련하여 기업이 활용하여 독자적으로 계획할 수 있을 만큼 상세한 가이드라인이 마련되어 있었고, 그 또한 지속적으로 개선된다는 점이 한국이 앞으로 벤치마킹해야 할 부분이다. 이러한 차이는 기본적으로는 정부의 기업 재해대책에 대한 중요성의 인식에 기반한 것으로 판단된다.

• 대한교통학회지
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• 제26권6호
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• pp.29-38
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• 2008

서울의 오피스 시장은 빠르게 성장하고 있으며, 앞으로도 그 성장세는 계속될 것으로 전망되고 있다. 그에 따라 오피스 시장에 관한 연구들이 많이 이루어지고 있다. 교통여건은 오피스 임대료를 결정하는 가장 중요한 요소중 하나지만, 교통여건이 오피스 임대료에 미친 영향을 실증적으로 규명한 연구는 매우 드문 실정이다. 이 연구는 교통여건이 오피스 임대료에 미친 영향을 규명하기 위해 도심 80개, 강남 96개, 여의도 74개의 오피스 빌딩을 대상으로 임대료 회귀모형을 구축하였다. 실증분석결과 교통여건은 오피스 임대료를 결정하는 중요 요인이며, 교통량이 많아져 교통혼잡이 발생할 경우 오피스 빌딩 임대료는 하락한다는 사실을 규명할 수 있었다. 또한 이 연구를 통해 서울의 3대 오피스 중심 지역(도심, 강남, 여의도)별로 교통여건이 오피스 임대료에 미치는 영향이 다르다는 점도 규명할 수 있었다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권2호
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• pp.1057-1069
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• 2017

The applications of Wireless Sensor Networks (WSN) are progressively adopting for various smart home services such as home automation, controlling smart home household appliances, constrained application services in a smart home, etc. However, enabling a seamless and ubiquitous WSN communication between the smart home appliances is still a challenging job. Therefore, in this paper, we propose a smart home control system using an Actuator based ZigBee networking (AZNET). The working of the proposed system is further divided into three phases, 1) an interference avoidance system is adopted to mitigate the effect of interference caused due to the co-existence of IEEE 802.11x based wireless local area networks (WLAN) and WSN, 2) a sensor-based smart light control system is used to fulfill the light requirement in the smart home using the sunlight with light source, and 3) an autonomous home management system is used to regulate the usage time of the electronic appliances in the smart home. The smart is tested in real time environment to use the sunlight with light sources in a various time of the day. Similarly, the performance of the proposed smart home is verified through simulation using C# programming language. The results and analysis revealed that the proposed smart home is less affected by the interference and efficient in reducing the energy consumption of the appliances available in the smart home scenario.

• 한국콘텐츠학회논문지
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• 제12권7호
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• pp.183-193
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• 2012

본 연구는 효과적인 갈등해소를 위한 공동체 형성 전략을 도출하는데 그 목적을 두고 있다. 지역공동체 관련 이론의 정립과 더불어 천안지역주민 조사를 통하여 전략방안을 모색해 보았다. 연구결과, 공동체의식과 주민참여의 상관성에서는 충족감, 연대감, 소속감이 높은 유의관계를 보였으며, 이중 소속감이 사회참여의 욕구에 크게 작용한다는 것을 알 수 있었다. 지역공동체 형성의 요건은 다음과 같다. 첫째, 다양한 지역의 특성과 주민들의 요구에 대응할 수 있는 지역공동체형성 전략의 적용이다. 둘째, 지역공동체의 형성을 위하여 지자체들의 적극적인 지원, 지역공동체의 자체적인 노력과 지역주민들의 협력과 이해가 필요하다. 우리가 생각하는 이상적인 지역공동체란 물적 풍요와 사회구조의 평등실현 뿐만 아니라 성숙된 관계를 이끌어가는 건전한 사고의 각성이 어우러져서 성립된다.

• Nuclear Engineering and Technology
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• 제22권4호
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• pp.326-336
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• 1990

최근 수행된 일련의 실험들을 통하여 핵연료 집합체 지지격자(Spacer Grid)의 존재가 냉각재상실사고시에 핵연료봉으로부터의 열제거에 긍정적인 효과를 미치고 있음이 밟혀졌다. 그 이유는 열원이 없는 지지격자가 연료봉보다 먼저 ？칭이 일어나며 물방울이 지지격자에 부딪쳐서 잘게 부수어져 증발이 쉽게 일어나게 되고 또한 난류효과를 증대시키는 요인이 되기 때문이다. 따라서 냉각재상실사고의 진행 과정에서 첨두피복관온도가 발생하는 재관수 구간의 수면 위쪽에서 유지되는 DFFB에서의 정확한 열전달을 계산하기 위해서는 이들의 고려가 필요하다. 본 논문에서는 DFFB에서 지지격자의 존재로 인해 물방울이 잘게 부수어져 증발이 쉽게 이루어지도록 하는 Droplet Breakup Model을 냉각재상실사고 최적해석 코드인 RELAP5/MOD2에 삽입하였다. 재관수 구간에서 지지격자의 영향을 체계적으로 조사한 FEBA실험에 대해서 검증계산을 수행하여 실험자료와 비교하였다.