Efficient time simulation method for predicting the 100-year extreme responses of an offshore platform

Offshore structures are exposed to random wave loading in the ocean environment and hence the probability distribution of the extreme values of their response to wave loading is required for their safe and economical design. To this end, the conventional (Monte Carlo) time simulation technique (CTS) is frequently used for predicting the probability distribution of the extreme values of response. However, this technique suffers from excessive sampling variability and hence a large number of simulated extreme responses (hundreds of simulated response records) are required to reduce the sampling variability to acceptable levels. In this paper, three different versions of a more efficient time simulation technique (ETS) are compared by exposing a test structure to sea states of different intensity. The three different versions of the ETS technique take advantage of the good correlation between extreme responses and their corresponding surface elevation extreme values, or quasi-static and dynamic linear extreme responses.

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Analysis on Equivalence between Transfer Function and Equivalent Circuit Simulation in General Hamiltonian Modeling

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.204-208.4896 ◽

2012 ◽

Vol 204-208 ◽

pp. 4896-4899

Author(s):

Jing Qian ◽

Yun Zeng ◽

Li Xiang Zhang ◽

Tian Mao Xu

Keyword(s):

Transfer Function ◽

Equivalent Circuit ◽

Circuit Simulation ◽

Hamiltonian Function ◽

Simulation Method ◽

Generator System ◽

Time Simulation ◽

Internal Parameters ◽

Hamiltonian Model ◽

System Stabilizer

Take generator system included AVR (automatic voltage regulator) and PSS (power system stabilizer) as an example, Using the time simulation method, Study the equivalence between the transfer function model and the equivalent circuit simulation, and establish the corresponding relations between the circuit structures, internal parameters and transfer function parameters, based on the energy of equivalent circuit, the Hamiltonian function of transfer function is derived indirectly, and the Hamiltonian model is established. The study in this paper provides a new way to establish generalized Hamiltonian model for linear system based on transfer function.

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The Research on Real-Time Simulation of Wavers Based Parallel DSP System

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.373-375.2175 ◽

2013 ◽

Vol 373-375 ◽

pp. 2175-2179

Author(s):

Ying Li ◽

Jing Qiu

Keyword(s):

Real Time ◽

Simulation Method ◽

Ocean Wave ◽

Practical Significance ◽

Real Time Simulation ◽

Wave Simulation ◽

Time Simulation ◽

Dsp System ◽

Low Efficiency ◽

The Waves

3D ocean wave simulation has long been hot issues in the field of computer graphics and real-time simulation and has practical significance in many areas of society. Complexity and randomness of the waves led to large areas of ocean wave simulation calculation exists for compute-intensive, low efficiency, memory requirements and other limitations. In response to the phenomenon of a decline in real-time with the fidelity lifting, this paper proposes a parallel simulation method, in which the wave data is calculated by each DSP and the results will be stitched as large ocean area. Experimental results show that the multi-DSP parallel processing method can satisfy the feeling of reality and real-time requirements of the waves at the same time, which will improve the system real-time performance without loss the wave details.

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Simulation-based Virtual Prototyping of Customized Catheterization Devices

Journal of Computing and Information Science in Engineering ◽

10.1115/1.1705667 ◽

2004 ◽

Vol 4 (2) ◽

pp. 132-139 ◽

Cited By ~ 7

Author(s):

Y. Y. Cai ◽

C.-K. Chui ◽

X. Ye ◽

J. H. Anderson ◽

K.-M. Liew ◽

...

Keyword(s):

Virtual Prototyping ◽

Vascular Anatomy ◽

Simulation Method ◽

Therapeutic Interventions ◽

Patient Specific ◽

Anatomic Variations ◽

Pathological Changes ◽

Time Simulation ◽

Simulation Based ◽

Vascular Catheterization

Human vascular systems have considerable anatomic variations. In diseased situation, significant pathological changes will be developed with the systems. However, vascular catheterization devices commercially available are essentially designed on normal or average anatomy. Their inadequacies in representing major deviations in human vascular anatomy may present problems during diagnostic or therapeutic interventions. A virtual reality (VR) based simulation method is described in this paper for prototyping of customized patient-specific catheterization devices. Techniques are developed to model patient-specific vascular network, to design catheterization devices, and to simulate physical-based interactions between blood vessels and the devices. Emphasis is made on the integration of normal and variant vascular models, the integration of modeling, visualization and interaction, and the integration of real-time simulation and virtual prototyping.

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High Flexibility Hybrid Architecture Real-Time Simulation Platform Based on Field-Programmable Gate Array (FPGA)

Energies ◽

10.3390/en14196041 ◽

2021 ◽

Vol 14 (19) ◽

pp. 6041

Author(s):

Ruyun Cheng ◽

Li Yao ◽

Xinyang Yan ◽

Bingda Zhang ◽

Zhao Jin

Keyword(s):

Real Time ◽

Simulation Method ◽

Hybrid Architecture ◽

Simulation Platform ◽

Real Time Simulation ◽

Interactive Operation ◽

Time Simulation ◽

Simulation Step ◽

High Flexibility ◽

Network Simulation Method

With the expansion of system scale and the reduction in simulation step size, the design of a power system real-time simulation platform faces many difficulties. The interactive operation of real-time simulation presents the characteristics of phased and centralized. This paper proposes selecting the appropriate simulation method for each sub-network according to the system operation requirements, and the sub-network simulation method can be changed with the change in system operation requirements in the simulation process. In order to change the sub-network simulation method in the simulation process, a high flexibility hybrid architecture real-time simulation platform based on FPGA was designed. The main body of the architecture runs in the high control mode of instruction flow and uses instruction flexibility to realize the requirement of changing methods. The algorithm modularity architecture is used as an auxiliary architecture to reduce the instruction cost and increase the computing power. Finally, the hybrid architecture real-time simulation platform was implemented in the Xilinx VC709 board (Xilinx corporation, San Jose, CA, USA), and the verification results show that under the same system scale, the hybrid architecture simulation platform combined with simulation method changing realizes shorter simulation step and complex interactive operation.

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Design of real-time simulation method for infrared earth sensor signal based on FPGA architecture

Journal of Physics Conference Series ◽

10.1088/1742-6596/1213/4/042033 ◽

2019 ◽

Vol 1213 ◽

pp. 042033

Author(s):

Yan Wang ◽

Ziyan Xie ◽

Jinjiang Zhang

Keyword(s):

Real Time ◽

Simulation Method ◽

Sensor Signal ◽

Real Time Simulation ◽

Fpga Architecture ◽

Time Simulation

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The enhancement of the prescribed track for unmanned air vehicles

Aircraft Engineering and Aerospace Technology ◽

10.1108/aeat-12-2019-0255 ◽

2020 ◽

Vol 92 (10) ◽

pp. 1469-1473

Author(s):

Oznur Usanmaz ◽

Murat Karaderili ◽

Ozlem Sahin ◽

Tamer Savaş

Keyword(s):

Real Time ◽

Traffic Control ◽

Simulation Method ◽

Flight Time ◽

Flight Distance ◽

Content Type ◽

Real Time Simulation ◽

Vehicle Simulation ◽

Unmanned Air Vehicle ◽

Time Simulation

Purpose Unmanned aerial vehicles (UAVs) are more affected by adverse wind conditions in especially landing. Therefore, they need to change the runway in use. In case of this change, to eliminate the uncertain maneuvers, there is a need for a special prescribed track. The purpose of this study is the construction of a prescribed track at a single runway to provide a facility to change the runway in use. Design/methodology/approach Two forms of prescribed tracks, as standard and alternate, were constructed for UAVs by taking into consideration the key parameters to design flight procedures. Both tracks were assessed in a real-time simulation method. Moreover, unmanned vehicle simulation was used for a validation process. Findings According to the real-time simulation results, 8.14 NM and 6.64 NM of flight distance and 5.43 min and 4.43 min of flight time for the standard and alternate prescribed tracks were found, respectively. The obtained results were in favor of the alternate prescribed track. Furthermore, the prescribed track was assessed and validated in both air traffic control and UAV simulations. The feedback of pilots and controllers was very positive for a prescribed track, as it provided them with foresight and time to take care in any situations. Practical implications The prescribed track in this paper may be applied by airspace designers and UAV users to perform safe and efficient landing in adverse wind conditions. Originality/value In this study, a prescribed track was constructed for UAVs. Quantitative results were achieved using a real-time simulation method in terms of flight distance and flight time. Additionally, validation of the prescribed track was achieved by unmanned air vehicle simulation.

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