선택한 단어 수는 입니다.
최소 단어 이상 선택하여야 합니다.
최소 단어 이상 선택하여야 합니다.
선택한 단어 수는 30입니다.
최대 10 단어까지만 선택 가능합니다.
최대 10 단어까지만 선택 가능합니다.
가설 설정
- The ICRS prediction procedure used in this study is summarized in Fig. 1. This procedure starts from generating an artificial earthquake motion compatible with the target response spectrum. The artificial earthquake motion may be a time-history acceleration as shown in Fig.
- The simulated and predicted earthquake responses at nodes 3 and 4 are compared in Fig. 17. The predicted response shows reasonable agreement with the measured response even with some differences in the time variation. The comparison of predicted and simulated mean ICRS shows good matches as shown in Fig.
제안 방법
- The artificial earthquake motion may be a time-history acceleration as shown in Fig. 2. The procedure also includes identification of the state-space equation by measuring the response and the impulse from impact tests. The seismic responses under generated artificial earthquakes are then predicted and converted to ICRS.
- The ICRS prediction procedure is presented and verified by numerical simulation tests using three structural models. From comparisons of the predicted and simulated ICRS of the numerical models, the proposed algorithm appears to efficiently predict the ICRS of the cabinet structures.
- Practically, with more times of impacts at each node, a more reliable estimation of the state space equation can be achieved. In this study, two times of impacts at each node were simulated to show the effectiveness and efficiency of the proposed procedure. Based on a set of input and output measurements, a statespace equation model was identified using N4SID.
- Numerical simulation tests for a given earthquake motion were performed on an electrical equipment cabinet to verify the algorithm of this study. The predicted seismic responses were obtained by applying the procedure proposed in this study.
- The ICRS prediction procedure is presented and verified by numerical simulation tests using three structural models. From comparisons of the predicted and simulated ICRS of the numerical models, the proposed algorithm appears to efficiently predict the ICRS of the cabinet structures.
- In this section, three different analytical models are presented to be used in the numerical verification of the proposed algorithm, which are a lumped-mass beam stick model, a frame model, and a 3-dimensional finite element model to represent the cabinet structure, respectively. The models were constructed by considering the characteristics of a seismic monitoring system cabinet for nuclear pore plants whose main functions are alarming and monitoring seismic signals at the site of the plant. As shown in Figure 4, the cabinet includes very complex units and components inside.
- This study proposes a procedure to estimate the ICRS of electrical equipment based on an in-situ vibration test using an impact hammer. The proposed procedure eliminates the uncertainty associated with constructing an analytical model of an electrical cabinet that has a complex mass distribution and stiffness.
- The simulated and predicted seismic responses were then converted to ICRS to verify the effectiveness of the proposed procedure. The comparison of mean ICRS from ten sets of simulated and predicted seismic responses shows a good convergence as shown in Fig.
- 14. This model was constructed by combining 3-dimension plate elements and frame elements. The plate elements represent the roof and exterior wall plates, interior diaphragm plates, and floor plates.
- This study developed a discrete-time state-space equation (SSE) to predict the equivalent seismic forces applied at the cabinet and a method to estimate the seismic responses of the cabinet by numerical integration of the equation of motion. This paper introduces the procedure to predict the ICRS and describes the numerical simulation tests for its verification.
- Further studies are required to extend this study to predict the ICRS of the cabinet and to present further verifications for more complex models. This study developed a discrete-time state-space equation (SSE) to predict the equivalent seismic forces applied at the cabinet and a method to estimate the seismic responses of the cabinet by numerical integration of the equation of motion. This paper introduces the procedure to predict the ICRS and describes the numerical simulation tests for its verification.
- The seismic response of a structure can be estimated after its dynamic characteristics are reasonably identified. This study proposes a procedure to estimate the ICRS of electrical equipment based on an in-situ vibration test using an impact hammer. The proposed procedure eliminates the uncertainty associated with constructing an analytical model of an electrical cabinet that has a complex mass distribution and stiffness.
- 8967 x 10-6m4. To predict the seismic response based on the SSE model, the equivalent earthquake force fe was calculated by idealizing the model to a lumped-mass system.
대상 데이터
- The frame elements were additionally modeled to represent the horizontal and vertical stiffeners in the interior of the cabinet. 108 frame elements and 203 plate elements were used to represent the stiffness of the model. The structural masses were automatically computed by inputting the mass density of the structural element.
이론/모형
- In this study, two times of impacts at each node were simulated to show the effectiveness and efficiency of the proposed procedure. Based on a set of input and output measurements, a statespace equation model was identified using N4SID. The order of the state-space equation was selected as 8 by inspecting the singular values obtained by Eq.
- The numerical simulation tests were performed in a manner similar to the lumped-mass beam stick model case. The impact hammering was applied at the four points from node 2 to node 5 on the frame model continuously in time, and the acceleration responses were also collected at these nodes.
- Various algorithms have been developed for identification of the discrete-time SSE. This study uses the N4SID algorithm proposed by Overschee and Moor [9, 10], which is a variant of the subspace identification method and uses very simple parameters. N4SID has major advantages that are non-iterative and rapidly converged.
후속연구
- [7] focused on verification of the predicting method by the shaking table test for a simple specimen. Further studies are required to extend this study to predict the ICRS of the cabinet and to present further verifications for more complex models. This study developed a discrete-time state-space equation (SSE) to predict the equivalent seismic forces applied at the cabinet and a method to estimate the seismic responses of the cabinet by numerical integration of the equation of motion.
- The proposed algorithm can be developed as a candidate algorithm for ICRS prediction of cabinet structures. It is expected that the procedure proposed in this study will be used in the SQ of electrical equipment installed in operating plants.
※ AI-Helper는 부적절한 답변을 할 수 있습니다.