• Journal of Korean Society of Coastal and Ocean Engineers
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• v.23 no.2
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• pp.139-146
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• 2011

The breaking wave pressure occurs when a plunging breaker instantaneously impinges on structural surface, and appears differently depending on whether or not to form air pockets at the instant of contact. The Wagner type normally forms a single pressure peak at the contact spot due to the direct collision of water volume to the structure whereas in the Bagnold type the time lagged oscillation of the air pocket causes pressure peaks even at areas away from the spot. In the present study, the Bagnold's impact pressure is numerically and experimentally investigated for the bulkhead of an underwater tunnel under construction which is subjected to nearby breaking waves. A numerical solver of Navier-Stokes equations was applied to reproduce the breaking waves near a bulkhead, and the results showed the Bagnold's impact pressure occurring on the back (land side) face of the bulkhead. The existence of the impact pressure was also verified by a hydraulic model testing, and it was found that the experimental results well conformed to their numerical counterparts.

• International Journal of Highway Engineering
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• v.12 no.4
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• pp.165-174
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• 2010

This study was conducted to evaluate the feasibility of expedite repairing of concrete pavements using precast concrete pavement method and to investigate the effectiveness of slab connection methods. In the demonstration construction, four slabs of jointed concrete pavements were replaced with the precast slabs. First, precast concrete slabs were designed and fabricated, then existing slabs were cut and removed, and finally precast slabs were installed. The slabs were leveled and pockets, holes, and space between the slab bottom and the underlying layer were grouted. From the demonstration construction, details about the design and construction of the precast pavements for repairing of pavements were evaluated. In addition, the slab connection methods such as pocket and hole connection methods were applied in the construction and the slab curling behaviors at the joints that include those connection methods were compared. The results showed that both slab connection methods were applicable, and the hole connection method was superior.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.10a
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• pp.803-806
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• 2016

'Pokemon Go',which is game program, provides a clue to solve the problem of healthcare in the sense of leading changes in behavior of the users. 'Pokemon Go'is a spin-off of the $Pok{\acute{e}}mon$ game series and uses Augmented Reality(AR) technology. AR, which can be said to complement the real world, has been used in many fields such as medical applications, broadcasting, manufacturing, the mobile sector as a wide range of technologies. In particular, the medical field as area of the active application from the start of AR, provides a great help in medical fields, that is accurate medical diagnosis and prevention of unnecessary dissection by synthesizing the patient information and the image of actual patient on three-dimensional data of the sensor such as MRI or ultrasonic wave. In this study, we analyze the VR technology trends, application examples, and the future of VR and AR based medical services in healthcare.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.1 no.2
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• pp.15-22
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• 1991

When $YBa_2Cu_3Ox$ is liquid-phase sintered at $925^{\circ}C$ in $O_2$ for 16h, liquid pockets are entrapped within the grains. The liquid pockets show a thin parallelepiped shape with short edge lengths in the c axis, even after reannealing $925^{\circ}C$ in $O_2$ for 16h. All grains in contact with the liquid matrix show the same shape. However, when liquid-phase sintered at 925^{circ}C in $N_2$ for 16h, the grains dispersed in the liquid matrix show a thicker parallelepiped shape than in $O_2$, and their shape remains intact even after reannealing at $925^{\circ}C$ in $N_2$ for 16h. The effect of atmosphere on the grain shape is expected to be due to the variation of oxygen vacancy concentraion in $CuO_2$ plane of tetragonal unit cell.

• The Korean Publising Journal, Monthly
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• s.135
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• pp.19-19
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• 1993

현재 네덜란드에서는 양장본이 줄고 상대적으로 페이퍼백이 늘고 있는 추세이며, 따라서 센츄럴 북 하우스에서는 여러 출판사가 동일한 규격의 포켓판 책을 제작해 유통비용을 줄이는 방안을 검토중에 있습니다. 책가격은 올라가고 1쇄의 부수는 줄어들고 있는 게 네덜란드의 출판계 현실입니다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.11a
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• pp.211-212
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• 2008

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.11a
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• pp.101-102
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• 2007

• 정보화사회
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• s.182
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• pp.8-11
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• 2006

유선과 무선 통신환경이 발달되면서 두 네트웍간 연동 또는 통합시킨 서비스가 속속 등장하고 있다. KT의 '원폰' 및 '안폰', 그리고 LG텔레콤의 '기분존' 이 대표적인 유무선 통합서비스이다. 이 외에도 '블랙베리' 등 e메일을 주고 받을 수 있는 서비스들도 있으며, 모바일 오피스를 구현한 SK텔레콤의 '포켓원' 도 유무선 통합서비스 계열이다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.1339-1340
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• 2013

• The Science & Technology
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• v.31 no.4 s.347
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• pp.75-80
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• 1998

기계가 말하고 알아듣는 시대가 빠른 걸음으로 다가오고 있다. 21세기 초에는 외국어를 모르는 사람들도 외국인과 대화할 때 거추장스럽게 통역관을 내세우지 않아도 된다. 통역용 소프트웨어가 내장된 전화기가 등장하는가 하면 포켓용 통역장치가 그때그때 대화내용을 우리말과 외국어로 옮겨 합성소리로 알려준다.