Multi-Platform Simulation of Infilled Shear-Critical Reinforced Concrete Frames Subjected to Earthquake Excitations

This paper proposes a multi-platform simulation method for seismic performance assessment of masonry infilled reinforced concrete (RC) frames, especially for those who tend to fail in shear during an earthquake due to inadequate reinforcing details. The method is based on a micro-macro modeling approach where a detailed finite element (FE) model of the RC frame is incorporated with a strut model of the infill wall. It takes advantage of the strut model in terms of computational efficiency and the FE model based on the Modified Compression Field Theory (MCFT) to capture the nonlinear behaviour of the RC frame with explicit modeling of the beam-column joint failure and shear failure of the frame. The proposed method is validated against previously tested frames subjected to lateral loads, and its advantages over the conventional struct models are demonstrated through both quasi-static and dynamic analyses.

Macro-Modeling for N-Type Feedback Field-Effect Transistor for Circuit Simulation

In this study, we propose an improved macro-model of an N-type feedback field-effect transistor (NFBFET) and compare it with a previous macro-model for circuit simulation. The macro-model of the NFBFET is configured into two parts. One is a charge integrator circuit and the other is a current generator circuit. The charge integrator circuit consisted of one N-type metal-oxide-semiconductor field-effect transistor (NMOSFET), one capacitor, and one resistor. This circuit implements the charging characteristics of NFBFET, which occur in the channel region. For the previous model, the current generator circuit consisted of one ideal switch and one resistor. The previous current generator circuit could implement IDS-VGS characteristics but could not accurately implement IDS-VDS characteristics. To solve this problem, we connected a physics-based diode model with an ideal switch in series to the current generator circuit. The parameters of the NMOSFET and diode used in this proposed model were fitted from TCAD data of the NFBFET, divided into two parts. The proposed model implements not only the IDS-VGS characteristics but also the IDS-VDS characteristics. A hybrid inverter and an integrate and fire (I&F) circuit for a spiking neural network, which consisted of NMOSFETs and an NFBFET, were simulated using the circuit simulator to verify a validation of the proposed NFBFET macro-model.

Inclusion of frequency dependences into prediction model of conducted electromagnetic emissions for a VFD motor system

This paper presents a quantitative prediction model of conducted electromagnetic emissions (EME) for a variable frequency drive (VFD) motor system based on the macro-modeling approach. This model relies on the effective representations of the frequency dependent characteristics of the parasitic behaviors between converter arms and heatsink, of shielded power cable, and of motor windings. The frequency dependent performances between converter arms and heatsink, and of the motor windings are obtained by processing measurement data. Then the vector fitting method (VFM) with passivity enforcement and circuit synthesis method are adopted to obtain the corresponding equivalent circuits. The equivalent circuit implementation of shielded power cable is achieved by applying a node-to-node admittance functions (NAFs) model, which considers the propagation phenomenon and frequency dependent losses accurately. The conducted EME model is compatible with commonly used transient circuit solvers since it only includes constant circuit elements. The conducted emissions of the VFD system are then evaluated by analyzing the common mode (CM) and differential mode (DM) voltages and currents.

Modeling and Simulation of Monolithic Single-Supply Power Operational Amplifiers

In this paper a simple PSpice (Personal Simulation Program with Integrated Circuit Emphasis) macro-model was developed, and verified for monolithic power operational amplifiers operated with a single-supply voltage. The proposed macro-model is developed using simplification and build-up techniques for macro-modeling of operational amplifiers and simulates the basic static and dynamic characteristics, including input impedance, small-signal frequency responses at various voltage gains, output power versus supply voltage, slew-rate-limiting, voltage limiting, output offset voltage versus supply voltage ripples, and output resistance. Furthermore, the macro-model also takes into account the ground reference voltage in the amplifier at a single power supply voltage. The model is implemented as a hierarchical structure suitable for the PSpice circuit simulation platform. The sub-circuit is built using standard PSpice components and analog behavioral modeling blocks. The accuracy of the model is verified by extracting the model parameters for single-supply power operational amplifier TDA2005 from ST Microelectronics as example. The effectiveness of the model is validated by comparing the simulation results of the electrical parameters with the corresponding measured values obtained by experimental testing of sample circuits. The comparative analysis shows that the relative error of the modeled large-signal parameters is less than 15%. Moreover, an error of 15% is quite acceptable, considering the technological tolerances of the electrical parameters for this type of analog ICs.

Macro Modeling of V-Shaped Electro-Thermal MEMS Actuator with Human Error Factor

The V-shaped electro-thermal MEMS actuator model, with the human error factor taken into account, is presented in this paper through the cascading ANSYS simulation model and the Fuzzy mathematics calculation model. The Fuzzy mathematics calculation model introduces the human error factor into the MEMS actuator model by using the BP neural network, which effectively reduces the error between ANSYS simulation results and experimental results to less than 1%. Meanwhile, the V-shaped electro-thermal MEMS actuator model, with the human error factor included, will become more accurate as the database of the V-shaped electro-thermal actuator model grows.