• Steel and Composite Structures
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• 제48권3호
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• pp.263-273
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• 2023

This paper investigates dynamic characteristics of a graphene nanoplatelets reinforced composite (GNPRC) sandwich doubly curved shell based on the first-order shear deformation theory (FSDT) and Hamilton's principle. The sandwich doubly curved shell is fabricated from a core made of honeycomb materials sandwiched by composite GNPs reinforced face-sheets. Effective materials properties of composite face-sheets are assumed to vary based on Halpin-Tsai micromechanical models and rule of mixture. Furthermore, the material properties of honeycomb core are estimated using Gibson's formula. The fundamental frequencies of the shell are computed with changes of main geometrical and material properties such as amount and distribution type of graphene nanoplatelets, side length ratio, thickness to length ratio of and side length ratio of honeycomb. The Navier's technique is presented to obtain responses. Accuracy and trueness of the present model and analytical solution is confirmed through comparison of the results with available results in literature. It is concluded that an increase in thickness to length ratio yields a softer core with lower natural frequencies. Furthermore, increase in height to length ratio leads to significant decrease in natural frequencies.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2002년도 정기총회 및 제4회 특별심포지움
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• pp.1-15
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• 2002

In the present paper, the marine reflection seismic survey, the survey using Chirp sonar, the detail topographic survey by narrow multi-beam sounding machine, the sea bottom geological condition survey by side-scan sonar, the sea bottom sampling by core sampler and the positioning by DGPS as the geophysical survey in shallow and transitional region are introduced by placing emphasis on hardware configuration.

• 건축역사연구
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• 제16권5호
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• pp.55-66
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• 2007

Through analysing on construction cases of stupa built in A.D. 7,8th, I have researched about these : constructive methods of inner soil of stupa, spatial compositions, characteristics of structures, arrangements of inner soil and etc. And cases analysed are six ; Mireuksajiseoktap(stone pagoda of Mireuksa Temple site), Gameunsajisamcheumgseoktap(three storied stone pagoda of Gameunsa Temple site), Goseonsajisamcheungseoktap(three storied stone pagoda of Goseonsa Temple site), Wolseong nawolliocheungseoktap(five storied stone pagoda in Nawonri, Wolseong), Guksagokseoktap(three storied stone pagoda in Guksa valley), Giamgokseoktap(three storied stone pagoda in Giam valley). Additionally we researched about inner soil of Sacheonwangsaji tapji(basement of stone stupa site in Sacheonwang Temple site) to speculate on composition of Synthetically, the foundation could be divided as core space and outer space. ; the former as structural function and the latter as ornamental function. And the core area could be divided again as center column space and buffer space. The relationship between core spaces and its formation are as belows; First, according to the area of foundation and scale of stone pagoda, formations of core are differed. As the scale of stone pagoda goes bigger, and the area of foundation goes larger, the structure of stone pagoda comprised by center column type and layered-core which endure upper load independently. On the contrary, as the scale of stone pagoda goes smaller, and the area of foundation goes lesser, the structure of stone pagoda tend to use only center column to endure upper part. Second, spatial composition of core area is comprised as two spaces, one which endure upper load and buffer space which absorb side pressure and upper pressure. The buffer space tend to be used in case of those structures which could not endure side pressure or have lots of joint. In some cases, it was located below the cover stone of foundation and gained upper load. And in case that have not gained pressure from side stone, the buffer space are comprised by smalle stone or roof tile to get structural supplement.

• International Journal of Internet, Broadcasting and Communication
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• 제15권4호
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• pp.185-190
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• 2023

With the continuous development of the game field, the subdivision of game types is becoming more and more precise. There are also more and more games that draw on some achievements in other fields in their game design. Among them are meta-fiction games based on metafiction. This article will explore whether the combination of a meta-fiction game and a side-scrolling game with a unique visual experience is appropriate. If the side-scrolling game is the external form of the game, then the meta-fiction game is the internal content core of the game. The degree of fit between the external form and the internal core will undoubtedly determine the lower limit and upper limit of the game quality. Based on alienation theory, this article takes several highly rated side-scrolling games on the market as examples to conduct a theoretical analysis on the compatibility of side-scrolling games and metafiction games. The analysis results suggest that compared to first-person games, side-scrolling games with a unique third-person perspective have the best compatibility with meta-games.

• Nuclear Engineering and Technology
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• 제31권5호
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• pp.476-485
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• 1999

In order to evaluate the gravity-injection capability to maintain core cooling after a loss-of-shutdown-cooling event during shutdown operation, the plant conditions of the Yong Gwang Units 3&4 were reviewed. The six cases of possible gravity-injection paths from the refueling water tank (RWT) were identified and the thermal-hydraulic analyses were performed using the RELAP5/MOD3.2 code. The core cooling capability was significantly dependent on the gravity-injection path, the RCS opening, and the injection rate. In the cases with the pressurizer manway opening higher than the RWT water level, the coolant was held up in the pressurizer and the system pressure continued increasing after gravity-injection. The gravity injection eventually stopped due to the high system pressure and the core was uncovered. In the cases with the injection path and opening on the same leg side, the core cooling was dependent on whether the water injected from the RWT passed the core region or not. However, in the cases with the injection path and opening on the different leg side, the system was well depressurized after gravity-injection and the core boiling was successfully prevented for a long-term transient. In addition, from the sensitivity study on the gravity-injection flow rate, it was found that about 54 kg/s of injection rate was required to maintain the core cooling and the core cooling could be provided for about 10.6 hours after event with that injection rate from the RWT. Those analysis results would provide useful information to operators coping with the event.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2012년도 제38회 춘계학술대회논문집
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• pp.597-602
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• 2012

화염유도로는 추진기관 시스템 시험설비 요소 중 추진기관시스템, 시험설비, 인적자원의 보호측면에서 매우 중요한 설계대상 중에 하나이다. 본 연구에서는 75톤과 300톤의 추진기관 시스템의 성능을 평가할 시험설비의 화염유도로 설계 방안에 대해 제안하였다. 설비가 구축될 장소의 경사로를 이용하여 화염유도로의 높이를 30m정도로 설계하였다. 개방형과 밀폐형 형상에 따라서 화염유도로의 적합성을 고려하였다. 또한 냉각을 위한 덕트를 core와 side분사 형태에 따라 모델링하였다.

• 대한기계학회논문집
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• 제16권6호
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• pp.1064-1074
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• 1992

본 연구에서는 제품에 분할선을 입력하여 상, 하판 금형을 만든 후 제품의 추 출을 방해하는 금형의 면들을 간섭검사를 통하여 찾아내는 프로그램을 개발하였다. 그리고 찾아낸 간섭면들을 이용하여 금형 설계자가 적합한 형상의 사이드 코어를 설계 할 수 있도록 설계과정을 CAD화 하였다.물론, 내부적으로는 사이드 토어의 생성과 동시에 금형의 형상도 수정되도록 프로그램 되어있다. 이러한 일련의 과정은 Fig.2 와 같이 나타낼 수 있는데 앞으로 2장에서는 금형의 생성 및 간섭면 검색 과정을 다루 고 3장에서는 사이드 코어의 설계 및 금형의 수정과정을 단계별로 자세히 설명하도록 하겠다. 그리고 결론에서는 현재 갭ㄹ한 프로그램의 효용 및 적용 범위, 문제점 및 개선 방안 등에 대해서 논의해 보겠다.

• Ocean and Polar Research
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• 제24권3호
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• pp.227-236
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• 2002

For ten firn cores, from both the eastern and the western side of Lambert Glacier basin (LGB), snow accumulation rate and isotopic temperature were measured far the recent 50 years. Results show that snow accumulation for five cores over the eastern side of LGB (GC30, GD03, GD15, DT001, and DT085) at Wilks Land and Princess Elizabeth Land increases, whereas it decreases at the western side (Core E, DML05, W200, LGB 16, and MGA) at Dronning Maud Land, Mizuho Plateau and Kamp Land. For the past decades, the increasing rate was $0.34-2.36kg\;m^{-2}a^{-1}$ at the eastern side and the decreasing rate was $-0.01\;-\;-2.36kg\;m^{-2}\;a^{-1}$ at the western side. Temperatures at the eastern LGB were also increased with the rate of $0.02%o\;a^{-l}$. At the western LGB it was difficult to see clear trends, which were confirmed by Instrumental temperature records at coastal stations. Although statistic analysis and modeling results display that both surface temperature and accumulation rate has increased trends in Antarctic ice sheet during 1950-2000, the regional distributions were much more different for different geographic areas. We believe that ice-core records at Wilks Land and Princess Elizabeth Land reflect the real variations of SST and moisture change in the southern India Ocean. For the Kamp Land and Dronning Maud Land, however circulation pattern was different, by which the climate was more complicated. The International Trans-Antarctic Scientific Expedition (ITASE) aimed to reveal an overall spatial pattern of climate change over Antarctic ice sheet for the past 200 years. This study points the importance of continental to regional circulation to annual-decadal scale climate change in Antarctica.

• 한국환경과학회지
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• 제20권7호
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• pp.829-837
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• 2011

A study on the grain size change, sedimentary facies and age indicator of volcanic tephra was analysis through four cores (P1 ~ P4) at the Ulleung Basin in the East Sea of Korea. The two cores (P1 and P2) were collected in the northeastern side of the Ulleung Basin (about 2,000 m in water depth), while the other two cores (P3 and P4) with the water depth of about 1,500 m and 1,700 m, respectively, were collected from the continental slope of the southwestern and western side of the Ulleung Basin. Four sedimentary facies and eight sedimentary subfacies were identified. The four facies were massive sand, bioturbated mud, homogeneous mud, and laminated mud. The eight subfacies were further divided as pumiceous ash massive sand, scorieaous massive sand, plain bioturbated mud, pyrite filamented bioturbated mud, distinctly laminated mud, indistinctly laminated mud, thinly laminated mud and homogeneous mud. The homogeneous mud was not found in the core of P3 which is located in the western side of Ulleung Basin (close to the Korean coast). In the case of laminated mud facies, the thinly laminated mud facies was dominated in the lower part of core sequences of the Ulleung Basin (P1 and P2), while the indistinctly laminated mud were overally distributed in the core sequences from the continental slope of Ulleung Basin. The Tephra layers from the core sequences of central Ulleung Basin were more dominated and distinctive than those from the core sequences of continental slope. This is related to the distance from the volcanic source and the amount of sediment supply. The core locations of Ulleung-Oki Tephra layers in the central Ulleung Basin were in the upper part of core sequences, while those in the continental slope were in the lower part of core sequences. This is indicated that the amounts of sediment supply in the continental slope after the Ulleung-Oki eruption were very high and different sedimentary environment between upper and lower of Tephra layer.

• 한국정보과학회논문지:시스템및이론
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• 제36권1호
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• pp.33-39
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• 2009

본 논문은 Advanced Encryption Standard(AES) 암호화 코아가 내장된 System-on-a-Chip(SoC)의 스캔 기반 사이드 채널 공격에 의해 발생될 수 있는 비밀 키 정보 누출 방지를 위한 효과적인 시큐어 스캔 기술을 제안한다. 본 논문에서 제안하는 시큐어 스캔 설계 기술은 어플리케이션에 최적화 되어있는 암호화 코아를 수정하지 않고 적용을 할 수 있다. 또한 SoC 상의 IEEE1149.1 제어기 표준을 유지하며 기존 방식보다 적은 면적 오버 헤드와 전력 소모 및 높은 고장 검출율을 갖는 기술을 제안한다.