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A new series of triphenylamine (TPA)‐functionalized isomeric polythiophenes are developed as hole transporting materials (HTM) for inverted tin‐based perovskite solar cells (TPSCs). Bithiophene (BT) is first functionalized with two TPA (electron donor; D) at 3 and 5 positions to give two structural isomeric compounds (3BT2D and 5BT2D). The functionalized BT2Ds are then coupled with 3,3′‐bis(tetradecylthio)‐2,2′‐bithiophene (SBT‐14)/3,3′‐ditetradecyl‐2,2′‐bithiophene (BT‐14) to produce structural isomeric polythiophenes (1‐4), which are compared to conventional poly[N,N″‐bis(4‐butylphenyl)‐N,N″‐bis(phenyl)‐benzidine] (poly‐TPD) as HTMs for TPSCs. With the appropriate alignment of energy levels with regard to the perovskite layer, the TPA‐functionalized polymers‐based TPSCs exhibit enhanced operational stability and efficiency. Moreover, the long thiotetradecyl chain in SBT‐14 with intramolecular S(alkyl)∙∙∙S(thio) interactions restricts the molecular rotation and has a strong impact on the molecular solubility and wettability of the film during device fabrication. Among all the polymers studied, TPSCs fabricated with 3‐SBT‐BT2D polymer exhibit the highest hole mobility as well as the slowest charge recombination and achieve the highest power conversion efficiency of 8.6%, with great long‐term stability for the performance retaining ≈90% of its initial values for shelf storage over 4000 h, which is the best efficiency for non‐PEDOT:PSS‐based TPSCs ever reported. [ABSTRACT FROM AUTHOR]

Properties of a compensator with adaptive balancing and harmonic blocking features for correcting the power factor of the load, balancing an unbalanced load, and reducing the waveform distortion caused by harmonic generating loads are presented in the paper. It combines a harmonic blocking compensator and a thyristor-controlled susceptance circuit which makes adaptive compensation possible. Therefore, it is referred to as an 'adaptive harmonic blocking compensator.' A harmonic blocking compensator is built of a series harmonic filter tuned to the fundamental frequency and a shunt capacitor. A suitable thyristor-controlled susceptance circuit, which contains a thyristor-switched inductor, needs to provide a variable susceptance without injecting an excessive amount of harmonic current. This paper presents the fundamentals, operation, and design of such a compensator. This research is supported with results from experiments with a laboratory prototype. Index Terms--Power system harmonic, reactive power, adaptive compensation, balancing compensation.

Reactive power compensators with thyristor switched inductors and shunt capacitors enable an adaptive compensation at the price of the harmonic distortion increase. This distortion is even higher if the compensator is controlled asymmetrically to reduce the effects of the load unbalance. Harmonic distortion may increase, moreover, because of the compensator resonance with the supply system reactance. This paper suggests a modification of the balancing compensator structure that reduces the harmonic currents injected by the compensator into the supply. The structure suggested also reduces the possibility of the compensator resonance with the supply source inductance. The paper discusses the required control range of the compensator susceptances and their frequency properties and suggests an efficient method of measuring the load parameters needed for the compensator control. Key Words: Unbalance, compensation, thyristor switched inductors.

A response of the author to the article concerning thyristor switched inductor and balancing an unbalanced system is presented. The author makes positive remarks and critical comments on the subject.

Purpose: This study attempts to explore and identify critical ethical incidents encountered by senior managers employed in international hotels in Taiwan. Design/methodology/approach: An in-depth interview was conducted to collect data from 22 senior managers. By using the critical incident technique (CIT) to analyze the interview data, 161 critical ethical incidents were identified and discussed. Findings: The analytical results show that the identified ethical incidents can be divided into 3 main categories, 7 sub-categories, and 13 underlying factors. The main and sub-categories include: (1) personal issues: personal integrity, executive leadership, and customer equity; (2) organizational issues: corporate integrity, organizational climate, and cross-cultural management; (3) external issues: customer integrity. Practical implications: Currently in Taiwanese hotels, ethics are not generally emphasized by management. The results of this research can contribute to hospitality ethics research and provide suggestions for ethics education and employee training in the hospitality industry. Originality/value: This study investigates critical ethical issues that exist in the hospitality workplace, with a focus on critical ethical concerns confronted by employees and managers in the hotel industry. [ABSTRACT FROM AUTHOR]

Comments on the study by Jen-Hung Chen et al. on the use of static var compensators (SVC) or thyristor-controlled susceptance circuits to balance a distribution system. Structure of the system; Means to overcome the resonant problem between the shunt capacitor and the system inductance.