• 제목/요약/키워드: Time response analysis

검색결과 4,032건 처리시간 0.036초

가상고정점기법이 적용된 잔교식 구조물의 응답스펙트 럼해석법 개선사항 도출 연구 (Study on the Improvement of Response Spectrum Analysis of Pile-supported Wharf with Virtual Fixed Point)

  • 윤정원;한진태
    • 한국지진공학회논문집
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    • 제22권6호
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    • pp.311-322
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    • 2018
  • As a method of seismic-design for pile-supported wharves, equivalent static analysis, response spectrum analysis, and time history analysis method are applied. Among them, the response spectrum analysis is widely used to obtain the maximum response of a structure. Because the ground is not modeled in the response spectrum analysis of pile-supported wharves, the amplified input ground acceleration should be calculated by ground classification or seismic response analysis. However, it is difficult to calculate the input ground acceleration through ground classification because the pile-supported wharf is build on inclined ground, the methods to calculate the input ground acceleration proposed in the standards are different. Therefore, in this study, the dynamic centrifuge model tests and the response spectrum analysis were carried out to calculate the appropriate input ground acceleration. The pile moment in response spectrum analysis and the dynamic centrifuge model tests were compared. As a result of comparison, it was shown that the response spectrum analysis results using the amplified acceleration in the ground surface were appropriate.

Comparative Expression of Stress Related Genes in Response to Salt-stressed Aspen by Real-time RT-PCR

  • Ku, Ja-Jung;Kim, Yong-Yul
    • 한국자원식물학회지
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    • 제21권3호
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    • pp.210-215
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    • 2008
  • Gene-expression analysis is increasingly important in biological research, with real-time reverse PCR (RTPCR) becoming the method of choice for high-throughput and accurate expression profiling of selected genes. However, this technique requires important preliminary work for standardizing and optimizing the many parameters involved in the analysis. Plant stress studies are more and more based on gene expression. The analysis of gene expression requires sensitive and reproducible measurements for specific mRNA sequence. Several genes are regulated in response to abitoic stresses, such as salinity, and their gene products function in stress response and tolerance. The design of the primers and TaqMan probes for real-time PCR assays were carried out using the Primer $Express^{TM}$ software 3.0. The PCR efficiency was estimated through the linear regression of the dilution curve. To understand the expression pattern of various genes under salt stressed condition, we have developed a unique public resource of 9 stress-related genes in poplar. In this study, real-time RT-PCR was used to quantify the transcript level of 10 genes (9 stress-related genes and 1 house keeping gene) that could play a role in adaptation of Populus davidiana. Real-time RT-PCR analyses exhibited different expression ratios of related genes. The data obtained showed that determination of mRNA levels could constitute a new approach to study the stress response of P. davidiana after adaptation during growth in salinity condition.

DEVELOPMENT OF TIMING ANALYSIS TOOL FOR DISTRIBUTED REAL-TIME CONTROL SYSTEM

  • Choi, J.B.;Shin, M.S.;M, Sun-Woo
    • International Journal of Automotive Technology
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    • 제5권4호
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    • pp.269-276
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    • 2004
  • There has been considerable activity in recent years in developing timing analysis algorithms for distributed real-time control systems. However, it is difficult for control engineers to analyze the timing behavior of distributed real-time control systems because the algorithms was developed in a software engineer's position and the calculation of the algorithm is very complex. Therefore, there is a need to develop a timing analysis tool, which can handle the calculation complexity of the timing analysis algorithms in order to help control engineers easily analyze or develop the distributed real-time control systems. In this paper, an interactive timing analysis tool, called RAT (Response-time Analysis Tool), is introduced. RAT can perform the schedulability analysis for development of distributed real-time control systems. The schedulability analysis can verify whether all real-time tasks and messages in a system will be completed by their deadlines in the system design phase. Furthermore, from the viewpoint of end-to-end scheduling, RAT can perform the schedulability analysis for series of tasks and messages in a precedence relationship.

A Study on response time measurement of FPD using statistical techniques of histogram

  • Lee, Yeun-Woo;Park, Gi-Chang;Lee, Sang-Dae
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.I
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    • pp.506-510
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    • 2005
  • As FPD technology is getting improved, there are a lot of issues on signal processing and analysis, and its relative importance has been increasing day by day. In particular, response time sad in the evaluation item of FPD has been measured by oscilloscope. In this paper, we propose an effective measurement method of response time in FPD. The proposed method is to calculate the rising/ falling time by using statistical techniques of histogram and analyzing an energy distribution. Ultimately, the method has proved the utility and reliability by comparison of oscilloscope

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LNG 탱크 방열구조의 슬로싱 충격 응답 해석법에 관한 연구 (A Study on the Sloshing Impact Response Analysis for the Insulation System of Membrane Type LNG Cargo Containment System)

  • 노인식;기민석;이재만;김성찬
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2011년도 정기 학술대회
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    • pp.531-538
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    • 2011
  • 멤브레인형 LNG 탱크의 구조적 안전성을 확보하기 위해서는 슬로싱에 의한 작용 압력과 구조응답을 정확히 평가할 수 있어야 한다. 탱크 방열구조에 작용하는 슬로싱 충격하중은 매우 불규칙적이며 이로 인한 구조 응답 역시 유탄성 거동을 포함하는 매우 복잡한 물리 현상이기 때문에 최신의 이론적 실험적 접근 방법을 동원하더라도 정확한 평가가 어렵다. 본 연구에서는 실험이나 수치해석으로부터 얻어진 슬로싱 압력 시계열을 이용하여 탱크 방열 구조의 구조응답을 간편하게 해석할 수 있는 방안을 제안하였다. 이 간이 해석법은 기본적인 삼각형 impulse 형태의 충격 압력에 대한 구조응답을 시간영역에서 과도응답해석법으로 계산한 후, 이렇게 구해진 구조물의 삼각형 응답함수를 조합하여 임의 형상의 압력 시계열에 대한 구조 응답을 구하는 방식이다. 여러 가지 예제 해석을 통하여 제안된 해석법의 타당성을 검토하였고, 이를 이용하여 실제 모형실험에서 얻어진 압력시계열을 바탕으로 구조응답을 계산하고 그 결과를 고찰하였다.

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응답시간으로 결정되는 최적 이용률 (The Optimal Utilization Determined By The Response Time)

  • Lim, Jong-Seul;Kim, Seong-Ho
    • 한국컴퓨터산업학회논문지
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    • 제2권9호
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    • pp.1155-1162
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    • 2001
  • 본 논문은 UNIX 시스템의 최적 이용률(Optimal Utilization)을 결정하는 방법을 제시한다. 제시된 방법은 사용자가 인내할 수 있는 응답시간(Tolerable Response Time)을 제공하는 범위에서 사용자에게 허용될 수 있는 최대 이용률이 최적 이용률이 된다는 정의(Definition)를 근거로 하여 개발되었다. 인내할 수 있는 응답시간이 길어지면 최적 이용률도 높아지므로 최적 이용률은 인내할 수 있는 응답시간의 최대값에서 구해진다. 인내할 수 있는 응답시간은 서비스 목표(Service Objective)가 주어지면 도출해 낼 수 있다. 본 논문에서는 인내할 수 있는 응답시간이 0.24초라는 것과 최적 이용률의 세 가지 구성요소는 %wio, %sys, %usr 이라는 것을 보여준다. 또한 최적 이용률을 결정하는 실제의 과정을 예시하기 위하여 UNIX 운영체제를 사용하는 IBM 컴퓨터의 최적 이용률을 구하는 과정을 예시한다.

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Spatiotemporal Routing Analysis for Emergency Response in Indoor Space

  • Lee, Jiyeong;Kwan, Mei-Po
    • 한국측량학회지
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    • 제32권6호
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    • pp.637-650
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    • 2014
  • Geospatial research on emergency response in multi-level micro-spatial environments (e.g., multi-story buildings) that aims at understanding and analyzing human movements at the micro level has increased considerably since 9/11. Past research has shown that reducing the time rescuers needed to reach a disaster site within a building (e.g., a particular room) can have a significant impact on evacuation and rescue outcomes in this kind of disaster situations. With the purpose developing emergency response systems that are capable of using complex real-time geospatial information to generate fast-changing scenarios, this study develops a Spatiotemporal Optimal Route Algorithm (SORA) for guiding rescuers to move quickly from various entrances of a building to the disaster site (room) within the building. It identifies the optimal route and building evacuation bottlenecks within the network in real-time emergency situations. It is integrated with a Ubiquitous Sensor Network (USN) based tracking system in order to monitor dynamic geospatial entities, including the dynamic capacities and flow rates of hallways per time period. Because of the limited scope of this study, the simulated data were used to implement the SORA and evaluate its effectiveness for performing 3D topological analysis. The study shows that capabilities to take into account detailed dynamic geospatial data about emergency situations, including changes in evacuation status over time, are essential for emergency response systems.

TRANSIENT PERFORMANCE OF AN SI ENGINE BY TRANSIENT RESPONSE SPECIFICATIONS

  • Kwark, J.H.;Jeon, C.H.;Chang, Y.J.
    • International Journal of Automotive Technology
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    • 제4권3호
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    • pp.109-117
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    • 2003
  • The analysis and evaluation of the transient performance by the transient response specifications under various acceleration speeds and types based on driver's typical acceleration habit are implemented by the experimental study to provide the appropriate direction for the transient control in a gasoline engine. The concept of the transient response specifications which consist of delay time, rising time, maximum overshoot and settling time, and the analysis method using them are introduced to evaluate the characteristics of the transient performance quantitatively. Furthermore four acceleration speeds and four acceleration types are set respectively to realize the various transient states which are similar to the real drive. Several performance parameters in terms of engine speed, manifold absolute pressure, fuel injection duration and air excess ratio are measured simultaneously during the various acceleration using a throttle actuator controlled by a PC. The transient response specifications characterized well the transient performance for the various acceleration speed and types quantitatively. Delay and rising time with increment of the acceleration speed became shorter, but settling time did longer. Intensified acceleration type appeared to be the most economical in view of fuel consumption, and linear acceleration type was found to have the least harmful emission concentration.

지진기반 가진효과를 고려한MW 급 풍력발전기 타워의 구조진동 특성연구 (Structural Vibration Characteristics of a MW-Class Wind Turbine Tower Considering Earthquake Base Excitation)

  • 김동만;박강균;김동현;김수현
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2009년도 춘계학술대회 논문집
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    • pp.616-620
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    • 2009
  • Modern wind turbines have been mainly erected in region where earthquake are rare or normally weak, especially Korea was thought as safety zone from earthquake. But recently, the earthquake occurs more and more frequently. So, the wind turbine design is required the structural and functional stability under the earthquake. The earthquake can influence normal operation, even if a weak earthquake. There are two ways to review the design under earthquake using Computer Applied Engineering (CAE). One is the Response Spectrum Analysis (RSA) the other is Time History Analysis (THA). In this research, dynamic response on time is obtained under the earthquake by taking into account ground accelerogram consistent with the relevant standards applied to the turbine foundation.

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An efficient seismic analysis technique for PCSG assembly using sub-structuring method and homogenization method

  • Gyogeun Youn;Wanjae Jang;Gyu Mahn Lee;Kwanghyun Ahn;Seongmin Chang
    • Nuclear Engineering and Technology
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    • 제56권6호
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    • pp.2120-2130
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    • 2024
  • This study significantly reduced the seismic analysis time of PCSG assembly by introducing a reduced model using homogenization and sub-structuring methods. The homogenization method was applied to the primary and secondary micro-channel sheets, and the sub-structuring method was applied to the PCSG module sets. Modal analysis and frequency response analysis were then performed to validate the accuracy of the reduced model. The analysis results were compared with the full model and it was confirmed that the reduced model provided almost the same analysis results as the full model. To verify the computational efficiency of the reduced model, the computational time was then compared with the full model, and it was confirmed that the modal analysis time was reduced by 3.42 times and the frequency response analysis time was reduced by 4.59 times.