• 대한조선학회논문집
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• 제48권2호
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• pp.171-177
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• 2011

Tensile tests were conducted at low temperatures for the steel materials which are used for outer shell of the vessels making transit through the polar regions. The selected steel materials were GL-DH32, GL-DH36 and GL-EH36. In comparison with the results at room temperature, the yield stress increases approximately by 10 to 13 percent at $-30^{\circ}C$ and by 13 to 19 percent at $-50^{\circ}C$ while the tensile strength increases about by 9 percent at $-30^{\circ}C$ and 11 to 14 percent at $-50^{\circ}C$. To obtain true stress-true strain, i.e. correct plastic hardening characteristics, Bridgman's(1952) necking correction formula was introduced taking triaxial state of stresses after onset of diffuse necking into consideration. Photographs of fractured surfaces were taken by using Scanning Electron Microscope immedately after tensile tests completed and one for GL-EH36 has been presented in this paper.

• Advances in concrete construction
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• 제10권2호
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• pp.113-125
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• 2020

This paper presents experimental results on bond-slip behavior of steel reinforced high-strength concrete (SRHC) after exposure to elevated temperatures. Three parameters were considered in this test: (a) high temperatures (i.e., 20℃, 200℃, 400℃, 600℃, 800℃); (b) concrete strength (i.e., C60, C70, C80); (c) anchorage length (i.e., 250 mm, 400 mm). A total of 17 SRHC specimens subjected to high temperatures were designed for push out test. The load-slip curves at the loading end and free end were obtained, the influence of various variation parameters on the ultimate bond strength and residual bond strength was analyzed, in addition, the influence of elevated temperatures on the invalidation mechanism was researched in details. Test results show that the shapes of load-slip curves at loading ends and free ends are similar. The ultimate bond strength and residual bond strength of SRHC decrease first and then recover partly with the temperature increasing. The bond strength is proportional to the concrete strength, and the bond strength is proportional to the anchoring length when the temperature is low, while the opposite situation occurs when the temperature is high. What's more, the bond damage of specimens with lower temperature develops earlier and faster than the specimens with higher temperature. From these experimental findings, the bond-slip constitutive formula of SRHC subjected to elevated temperatures is proposed, which fills well with test data.

• 전자공학회논문지C
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• 제34C권2호
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• pp.12-18
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• 1997

An efficient synthesis method of cellular architecture FPgA is proposed in this paper. To generate a logical representation called complex term which is to be directly mapped onto the cellular architecture FPGA, and SO or ESOP minimization tool was used in previous methods. Instead, we use a logic function transformed into BDD (binary decision diagram) in the actual generation of the complex temrs. In this process it estimates the cost(i.e. the number of complex terms) for three branches, 0-branch and 1-branches. This process is continued over the whole BDD to do such computation, and we observed that the number of complex terms has been reduced compared to the previous results.

• 한국조경학회지
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• 제18권3호통권39호
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• pp.137-141
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• 1990

This study was carried out to investigate the propagation methods of the Rhododendron micranthum as a landscape plant The results obtained are as follows :　1. The optimum temperature for seed germination was $20^{\circ}C$, and the seed germination needs light. 2. GA and thiourea did not affect the seed germination under light, but GA gad substitutive effect. 3. 87% and over of germination rates were obtained in room temperature and $5^{\circ}C$ dry storages. 4. The rooting rate was high on sandy loam, vermiculite, and vermiculite 50%+sand 50%, at softwood and hardwood cutting(hardwood ; 45~48%, softwood ; 45~48%). 5. The significant effects on rooting were found with the treatment of NAA 500~2000ppm.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2005년도 추계종합학술대회
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• pp.643-646
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• 2005

This paper presents CARMA (Cycle-Accurate Retargetable Micro-Architecture) as efficient framework for SoC-centric pipelined instruction-set architectures. It is based on ADL (Architecture Description Language) and provides more concise and manifest semantics to describe behavior of instruction set by mixing efficiency of instruction-set simulators and flexibility of RTL simulators. It exploits new timing model method based on process scheduling so it can support general timing model with cycle accuracy for large-scaled architectures usually used in SoC multimedia chip-set. According to experiments, the proposed framework was shown to be 5.5 times faster than HDL and 2.5 times faster than System-C in simulation speed so it is applicable for complex instruction-set pipelined architectures.

• IEIE Transactions on Smart Processing and Computing
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• 제3권6호
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• pp.353-357
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• 2014

This paper, presents an efficient hardware architecture of high performance SVC(Scalable Video Coding). This platform uses dedicated hardware architecture to improve its performance. The architecture was prototyped in Verilog HDL and synthesized using the Synopsys Design Compiler with a 65nm standard cell library. At a clock frequency of 266MHz, This platform contains 2,500,000 logic gates and 750,000 memory gates. The performance of the platform is indicated by 30 frames/s of the SVC encoder Full HD($1920{\times}1080$), HD($1280{\times}720$), and D1($720{\times}480$) at 266MHz.

• Geomechanics and Engineering
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• 제6권6호
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• pp.577-592
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• 2014

The methods for estimating in-situ hydraulic conductivity ($k_{hp}$) and coefficient of consolidation ($c_{hp}$) in the horizontal direction from piezocone penetration and dissipation test results have been investigated using test results at two sites in Saga, Japan. At the two sites the laboratory values of hydraulic conductivity ($k_v$) and coefficient of consolidation ($c_v$) in the vertical direction are also available. Comparing $k_{hp}$ with $k_v$ and $c_{hp}$ with $k_v$ values, suitable methods for estimating $k_{hp}$ and $c_{hp}$ values are recommended. For the two sites, where $k_{hp}{\approx}k_v$ and $c_{hp}{\approx}2c_v$. It is suggested that the estimated values of $k_{hp}$ and $c_{hp}$ can be used in engineering design.

• 한국통신학회논문지
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• 제15권1호
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• pp.58-70
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• 1990

본 논문에서는 저 전송률 비디오 코덱의 영상 데이터 압축을 위한 실시간 이차원 이상여현변환기 구현에 대해 기술한다. 제안된 구조는 벡터 내적 연산의 병렬 처리에 효율적인 분산연산을 이용하였으며 동시성을 최대로 활용하고 있어 CCITT에서 제안하는 완전 CSIF 30 프레임/초의 처리성능을 만족한다. 또한 제안된 구조를 비트 수준으로 모의시험을 수행하여 CCITT에서 제안하는 IDCT 정확도 사양을 만족함을 보였다. 실제로 효율적인 VLSI 실현을 위해 설계방법론을 연구하고 SUN3/150C를 중심으로 모듈발생기 지향적 설계환경을 구축하였다. 구축된 설계환경을 이용하여 제안된 구조의 핵심모듈을 이중 금속선 2m CMOS 기술로써 구현하였으며 설계된 이차원 DCT 칩의 크기는 약 3.9mmx4.8mm이다.

• 국제지역연구
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• 제20권2호
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• pp.195-214
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• 2016

지금까지 우리나라의 도시 간 연계는 산업적 여건을 기반으로 한 경제적 요구에 의해 이루어져 왔다. 그러나 국제적 가치실현에 대한 고려와 국내외 수요와 여건변화에 대응하기 위해서는 경제뿐만 아니라 환경과 사회적 측면을 포괄하는 방안마련이 필요하다. 특히 환경적인 문제는 개별 도시의 노력만으로는 불가능하기 때문에, 지방정부 간의 협력이 중요하다. 국내에서는 도시 간 복합적인 이해관계에 의해 다양한 방법으로 도시 간 연계가 추진되고 있다. 도시 간 연계는 서로 다른 도시 간 교류에 의해 창조적인 환경을 조성하는 촉매 작용을 하고 있으며, 그 목적과 과정 및 결과가 도시의 환경 사회 경제적 지속가능성 측면에서 나타나고 있다. 이에 본 연구는 국내외 도시 간 연계의 사례를 환경 사회 경제적 가치를 추구하는 유형별로 구분하여 분석한다. 이를 통해 도시 간 연계의 중요성에 대해 환기(喚起)하고 성공적인 도시 간 연계 실현과 활성화를 위한 방향을 모색하고자 한다. 본 연구의 결과는 향후 사업의 유형별로 성공적 도시 간 연계를 달성하기 위한 방향 설정에 길잡이가 될 수 있다.

• 한국조경학회지
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• 제32권6호
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• pp.82-94
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• 2005

This study was undertaken to measure and analyze the thermal environment characteristics of the grey permeable cement concrete pavement(GPCCP), the permeable cement concrete brick pavement(PCCBP) compared with impermeable cement concrete pavement(ICCP) and bare soil(BS) under the summer outdoor environment. Following is a summary of major results. 1) The peak surface temperature was greatest in the GPCCP$(54.2^{\circ}C)$ followed by ICCP$(47.2^{\circ}C)$ rut August 2, 2002, the hottest day$(35.3^{\circ}C\;of\;highest\;temperature)$ during the experiment; peak temperature in the ICCP and BS were $45.5^{\circ}C)$ and $45.3^{\circ}C)$ respectively. 2) Analysis of heat budget of the pavements has revealed that the heat environment was worse in the GPCCP than that in the ICCP and that this was mainly due to a low albedo in the former(0.2) relative to that of the latter(0.4). 3) Analysis of heat budget of the pavements has revealed that the heat environment was worse in the GPCCP than that in the PCCBP, BS and that this was mainly due to a decreased latent heat resulting from a time dependent decreasing impact of rainfall. 4) It is necessary to make cool pavements to further studies on light-colored surface materials for attaining high albdo and construction methods which can enhance the latent heat through the continuous evaporation from pavements surface. 5) Vertical arrangement of pavement layers has not been considered in the present study, which has been focuses on the heat characteristics of the surface layer materials. Accordingly, future studies will have to be empasized on pavement methods including the vertical arrangement of the pavement layers.