Tungnan University

This study proposes a robust proportional integral-fractional order proportional derivative-fractional order proportional derivative (PI-FOPD<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup>) cascade controller to stabilize stable and unstable high-order time delay (HOTD) processes satisfying pre-specified gain and phase margin (GPM) specifications. This method employs two cascaded robust fractional-order PD (FOPD) controllers and a PI controller to enhance tracking performance, ensure robustness, and withstand disturbance-induced effects. The two robust FOPD controllers accelerates transient response. The PI controller reduces steady-state error. These three independent and robust controllers are designed successively, consistently satisfying the pre-specified GPM specifications. This method is applicable to both integrating and non-integrating HOTD processes with minimum-phase or non-minimum-phase zeros. It does not require any delay approximation or model order reduction. Finally, an illustrative example proves the effectiveness of the presented method.

This study proposes a direct torque control (DTC) application-specific integrated circuit (ASIC) equipped with a neural network and a fuzzy hysteresis controller to achieve seamless control of a three-phase induction motor. In the proposed DTC system, feedback currents and voltages measured at the stator are fed into the hysteresis controller and a switching table. Subsequently, six-arm voltages are generated based on the voltage vector selector table to drive the RM5G inverter. However, severe switching noise is present in the power transistors of the inverter. These problems lead to numerous large ripples, instability, and delayed torque and flux responses at the stator. To address the aforementioned challenges, this study proposes a fuzzy controller to enhance flux signals. This controller incorporates a fuzzifier, a fuzzy rule base, and a defuzzifier. Additionally, a backpropagation neural network control is employed to improve torque signals. The multilayer neural network is utilized not only to calculate torque rapidly but also to enhance calculation accuracy. The proposed control method effectively reduces flux and torque errors, facilitating smooth control of the three-phase induction motor. After functional verification on an FPGA board, the proposed design is implemented on an ASIC fabricated using the TSMC <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$0.18-\mu \mathrm{m}$</tex> CMOS process. The results indicate a chip area of approximately <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$0.959\times 0.9584\text{mm}^{2}$</tex> and a power consumption of 2.2524 mW at a supply voltage of 1.8 V and an operating frequency of 10 MHz.

Interactive two-input two-output processes with time delays (TITOTD) generally have strong loop interactions and exhibit complex response characteristics. This study develops an alternative method to rapidly and graphically tune optimal and robust decentralized PID (ORDPID) controllers to stabilize TITOTD systems using the designer-defined frequency domain robustness specifications. To eliminate loop interactions, a decoupler is initially used to decompose the TITOTD system, so two independent time-delayed single-input single-output subsystems (SISOTD) are derived. To guarantee the frequency domain specifications for a controlled system in terms of gain margin (GM) and phase margin (PM), each SISOTD subsystem is incorporated with a gain-phase margin tester (GPMT). Without approximating the delay terms and reducing the orders of the SISOTD processes, the stability equation method determines the GM and PM-associated boundaries in the parameter plane. For each decoupled SISOTD process, a GM and PM specification-oriented region (GPMSOR) that encloses all admissible robust decentralized PID (RDPID) controllers is graphically characterized in the parameter plane. Two independent ORDPID controllers are searched within the determined GPMSORs by minimizing the IAE or the ISE performance index. For verification, the determined ORDPID controllers are evaluated using the original TITOTD processes with four simulation examples from the literature.

The possibility of a normal distribution indicates that few particles are in the same phase during a breath and their reflections can be observed on the chest wall, then a few explosive waves with relatively large power occurr occasionally. Therefore, the one-cycle sine wave which is simulated as a single burst of the explosive effect phenomenon penetrates through the chest wall and was analysed to explore the reason of the crackle sounds. The results explain the differences between the definitions of crackle proposed by Sovijarvi et al. (2000a). The crackles in the lungs were synthesised by a computer simulation. When the coarse crackles occur, the results indicate that higher burst frequency carriers (greater than 100 Hz) directly penetrate the bandpass filter to simulate the chest wall. The simulated coarse crackle sounds were low pitched, with a high amplitude and long duration. The total duration was greater than 10 ms. However, for a lower frequency carrier (approximately 50 Hz), the fundamental frequency component was filtered out. Therefore, the second harmonic component of the lower frequency carrier, i.e., the fine crackle, penetrated the chest wall. Consequently, it is very possible that the normal lung sounds may contain many crackle-shaped waves with very small amplitudes because of the filtering effects of the chest wall, environment noises, electric devices, stethoscopes, and human ears, the small crackles disappear in the auscultations. In addition, our study pointed out that some unknown crackles of the very low frequency under the bandwidth of the human ears cannot penetrate the airways and be detected by medical doctors. Therefore, it might be necessary to focus advanced electronic instrumentation on them in order to analyse their possible characteristics for diagnosis and treatment of the respiration system.

In this study, we utilised multi-layer perceptron neural networks (MLPNNs) to assess the issue of school closures. Specifically, this study uses the MLPNN model to conduct learning assessments to identify schools that may suffer from poor management. The empirical findings are briefly summarised as follows: (1) The research shows that more than half of the private schools in this study will face bankruptcy. In Taipei City, out of the 23 existing private schools, only four operate normally, while the remaining 19 private vocational high schools require assistance. About 12 schools face severe problems in terms of poor management, accounting for 63% of the total, while seven schools had a prediction value below 50, indicating a severe problem. These schools have expressed an immediate need for government assistance. (2) According to the MLPNN model in this study, reducing the number of full-time teachers is a primary factor contributing to school closures. First, since full-time teachers are a fixed cost, the dismissal of teachers tends to be prioritised to bring down school management costs. This, in turn, reduces the teacher-student ratio. Other factors that contribute to school bankruptcy are dismissing staff and part-time teachers, reducing expenditure, and poor operational maintenance. When the above policies are implemented in schools with poor management, a vicious cycle is created, leading to the bankruptcy of schools.

Abstract In Taiwan, the digitalization of banks has imparted a future trend and a national financial technology (FinTech) policy. This paper aims to study which factors will affect the promotion of digital banking amongst digital accounts. Categorically, we applied the principal components analysis (PCA) method to analyze and identify the main factors of digital banking development. In addition, this study used three years of data from 2017 to 2020 since the data were relatively comprehensive and included all the large financial holding companies (15 in total) in Taiwan. The empirical findings can briefly be summarized as follows: a bank that wants to promote digital accounts must start with a credit card since that is what digital finance must be bound to. They also need to let people know that digital accounts have many advantages, such as no deposit limits or interest-free cross-bank withdrawals. There are a few crucial factors that need to be considered, including the number of free transfers, the card in force, active cards, and the number of free withdrawals. If banks effectively promote and attract people to apply for digital accounts, it could strongly contribute to the development of digital banking in Taiwan. JEL classification numbers: C45, G10. Keywords: Financial technology, Digital banking, Digital account, Principal components analysis.