• Journal of the Institute of Electronics Engineers of Korea CI
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• v.45 no.6
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• pp.68-76
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• 2008

It is difficult to maintain mutes in the mobile ad hoc network (MANET) due to the high probability of disconnected routes break by frequent change of topology. The links can have the different reliability about data transmission due to these characteristics. Hence a measure which can evaluate this reliability and a algorithm which reflects this are required. In this paper, we propose routing algorithm based on reliability about transmission. First the bayesian inference which infers the hypothesis by past information is considered to obtain the link's transmission reliability. The other is that the link-based reliability estimation model which considers each link's reliability additionally is proposed while the standard uses only Dijkstra's shortest path algorithm. the simulation results using NS-2 show that the performance of proposed algorithm is superior to the standard OLSR in terms of throughput and stability.

• Aerospace Engineering and Technology
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• v.6 no.2
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• pp.150-156
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• 2007

In this paper, we focus on the fault detection and isolation(FDI) method for inertial navigation system with three two-degree of freedom dynamically tuned gyros(DTG) on orthogonal sensor configuration. we propose the FDI method which can detect the fault of each DTGs rather than the fault of each sensing axis. The proposed FDI method is separated into two FDI modules according to the fault magnitude in order to improve the reliability of fault detection information. For large fault detection, only instantaneous DTG measurement is used to detect a fault DTG within a short time. For small fault detection, the integrated value of DTG measurements are used to detect a fault DTG. It takes a more time to detect a fault but it serves more reliable fault detection information. Using the proposed FDI method with consideration of DTG fault characteristic, we could find out a fault DTG successfully.

• Journal of Korea Game Society
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• v.8 no.3
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• pp.15-22
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• 2008

Recently, Our average life span of korean people is extended and fast-growing an elderly population caused by Being Improved our living conditions and medical science level. Our another problems which being faced by an aging population are that marked psychological and social changes of the aged. The psychological changes of the aged is related to how they make their living and it strong influences on their successful aging process. For health of the aged, there is an urgent need of recreation which can be social activities to void decline their own process of thinking and the executive ability to adapt for controlling health. Therefore, thepurpose of this recreation Courseware program is to help the alienated minorities to achieve the optimal health and best quality of life based on the knowledge of the social-activities and to understand the korean traditional culture plays. Finally, This study could contribute it as a baseline model for the empirical study and to develop further recreation program for the elderly social activities and sufficient for needs of understanding our traditional culture plays.

• The Journal of the Korea Contents Association
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• v.12 no.1
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• pp.112-124
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• 2012

The remarkable development of digital technologies and the success of 3D stereoscopic films have led to started drawing attention to stereoscopic images. The stereoscopic images have not become a passing fad in the present time unlike in the past, but have constantly showed their potentials. Unfortunately, the domestic stereoscopic images market is faced with difficulties, such as lack of the capital strength and of insufficient production infrastructure, and the production of 3D from 2D. As a result, it is not easy to produce creative stereoscopic animation contents. Therefore, in Korea, more efforts should be made in accumulating a plenty of data on production techniques. In order to make film production reflecting stereoscopy and effective stereoscopic implementation, which are necessary to produce high-quality stereoscopic contents, this thesis gave an explanation about a production technique studied on the basis of 3D graphic. Stereoscopic images are definitely one of the most promising image contents in the 21st digital contents industry. For the reason, in order to produce stereoscopic animation contents with high quality, fundamental studies on the stereoscopic images should be performed in a constant and cautions way.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.213-213
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• 2011

남강은 낙동강에 유입되는 지류 중 가장 큰 하천으로서 낙동강 하류의 수질에 매우 큰 영향을 미치고 있다. 남강댐은 저수 용량에 비해 유역면적이 주요 저수지들에 비하여 월등하게 크므로 홍수시 순간적으로 다량의 유량 및 오염물질이 방류되어 낙동강에 유입되는 특성을 가지고 있다. 남강댐은 서북측에서 유입되는 경호강과 남쪽에서 댐축과 가까이 유입되는 덕천강이 공간적으로 멀리 떨어져 있음으로 인해, 주요 유입물질이 유입되는 시기에 횡방향 및 종방향으로 농도차이를 나타내고 있으며, 과거에 설치되었던 댐이 수중에 존재함으로 인해 국지적인 정체현상이 발생하고 있다. 남강은 현재 경남권은 물론, 거제 및 부산권의 용수원을 공급하거나 예정으로 있으므로 수질관리에 가장 큰 우선순위를 두어야 한다. 남강댐의 합리적인 수질관리를 위해서는 호 내의 공간적 시간적 수질변화에 대한 이해와 수질변화 여건에 있으며 이용되는 만큼 호 내의 정밀한 유체거동 해석이 필수적이다. 본 연구에서는 남강댐의 수리-수질 특성을 진단하고 예측하기 위하여 3차원 수리동역학 모델인 EFDC와 수질모델인 WASP을 연계하여 사용하였다. 유량 경계조건은 한국수자원공사 및 국가수자원관리 종합 정보시스템(WAMIS)의 남강댐 운영 자료를 바탕으로 남강댐의 유입량과 유출량 자료를 작성하였다. 남강으로 유입되는 지천 및 호 내의 수온, SS 및 수질농도 등은 환경부의 물환경정보시스템의 월 측정자료를 사용하였으며, 기상조건은 진주 기상대의 자료를 사용하였다. 본 연구에서 가용한 입력자료를 이용하여 남강댐의 수리 및 수질 및 부유물질 특성을 모의하였으며 EFDC-WASP 모델을 이용하여 성공적인 보정이 가능한 것을 확인하였다. 그러나 자세한 분석과 대책을 수립하기 위해서는 남강댐의 유입 수질 및 유량 자료에 대한 실질적인 모니터링이 수행되는 것이 필요하다고 판단된다.

• Journal of Technology Innovation
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• v.18 no.1
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• pp.153-175
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• 2010

Firms must focus on innovative activities via R&D investment in order to secure competitive advantage and sustainable growth. However, their innovative activities do not always result in successful outcomes and are often obstructed by uncertainty and non-appropriability of technology being developed and by insufficient internal resources and capabilities to tap into it. In this situation, collaboration with external partners can be a part of good alternative strategy to solve those problems. This paper aims to analyze what factors lead to Korean manufacturing companies’ decision to collaborate with external partners for technology innovation. For empirical analysis, we used the Korean Innovation Data compiled by STEPI, government-funded research institute in Korea. The research findings are: 1) firms tend to participate in external collaboration for product innovation with greater firm size, more past collaboration experiences and when they belong to high-tech industries 2) unlike our expectation, our chosen ‘innovation-impeding’ factors are found not to contribute to the enhancement of collaboration for product innovation.

• Journal of Chest Surgery
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• v.41 no.1
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• pp.61-67
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• 2008

Background: Conventional ascending aortic cross clamping is often limited. This study was carried out to evaluate the safety and efficacy of an endovascular aortic clamping technique with an intraaortic balloon catheter. Material and Method: From April 2004 to January 2007, surgery with endoaortic clamping was performed in seven patients. A retrograde access perfusion (RAP) catheter was used in six patients and a Pruitt's balloon catheter in two patients. The indication for the operation was a retrosternal pseudoaneurysm of the aortic root in six patients, diffuse calcification of the ascending aorta with aortic regurgitation in 2 patients and an atrial septal defect in one patient. Five patients had at least two prior cardiac surgeries. Result: Successful insertion of the catheter and endoaortic clamping was achieved in all patients. Conclusion: The endovascular aortic clamping technique with a balloon catheter was a useful alternative method for patients in whom conventional cardiac surgery was limited.

• Journal of Internet Computing and Services
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• v.12 no.2
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• pp.47-53
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• 2011

When some sensors under Wireless Sensor Networks fail or become energy-exhausted, redundant mobile sensors might be moved to recover the sensing holes. Within rugged terrain where wheeled sensors are unsuitable, other type of mobile sensors, such as hopping sensors, are needed. In this paper, we address the problem of relocating hopping sensors to the detected sensing holes. Recent study for this work considered the relocation using the shortest path between clusters; however, the shortest path might be used repeatedly and create other sensing holes. In order to overcome the mentioned problem, we propose relocation schemes using the most disjointed paths or multi-paths. Simulation results show that the proposed schemes guarantee more balanced migration distributions of efficient sensors and higher movement success ratios of required sensors than those of the shortest path-based scheme.

• The Journal of the Korea Contents Association
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• v.11 no.5
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• pp.157-171
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• 2011

James Cameron's Avatar was a stunning success for digital characters. Digital animation character creation was not suddenly enabled by visual technology, rather it was a result of numerous attempts of combining animation and live action film with the help of technology advancement. Two pioneers in this field are James Cameron and Robert Zemeckis. Although continuous interest and research in visual technology existed, the two directors differed in how they viewed the use of technology. The difference is demonstrated in their two recent movies which will be covered in details. How these two directors differed in their approach remains a topic of study for us who continuously are exposed on advance visual technology and our reaction to the changing nature of the industry.

• The Journal of the Korea Contents Association
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• v.12 no.7
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• pp.40-53
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• 2012

In the past, the elements that determine the movie performance were directors, movie stars, the number of opening screens, on-line ratings or distributing agencies. However, the word-of-mouth effect has changed this trends. So the influence of word of mouth grows more and more strong at this stage of the Internet and smart phones being widely prevalent. I fix my sight upon SNS which is one of the medium of arousing the word-of-mouth effect, and I have a purpose to cast light upon a real example of the influence of SNS on the movie performance. The way is to analyze SNS activities that accompany the process of production and showing of , which is said to have had an beneficial effect of SNS among the enormously successful movies last year. It is relevant to provide a new milestone regarding the movie performance through the successful case of SNS activities by examining the word-of-mouth activities through SNS in the manner of the period division of the pre-release, the early stage of release and the maturity.