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Auxiliary power system is an indispensable part of the train; the auxiliary systems of both electric locomotives and EMUs mainly are powered by one of the two ways, which are either from auxiliary windings of traction transformers or from DC-link voltage of traction converters. Powered by DC-link voltage of traction converters, the auxiliary systems were maintained of uninterruptable power supply with energy from electric braking. Meanwhile, powered by traction transformers, the auxiliary systems were always out of power while passing the neutral section of power supply grid and control system is powered by battery at this time.

Uninterrupted power supply of auxiliary power system powered by auxiliary winding of traction transformer was studied. Failure reasons why previous solutions cannot be realized are analyzed. An uninterruptable power supply scheme for the auxiliary systems powered by auxiliary windings of traction transformers is proposed in this paper. The validity of the proposed scheme is verified by simulation and experimental results and on-site operation of an upgraded HXD3C type locomotive. This scheme is attractive for upgrading practical locomotives with the auxiliary systems powered by auxiliary windings of traction transformers.

This scheme regenerates braking power supplied to auxiliary windings of traction transformers while a locomotive runs in the neutral section of the power supply grid. Control objectives of uninterrupted power supply technology are proposed, which are no overvoltage, no overcurrent and uninterrupted power supply.

The control strategies of the scheme ensure both overvoltage free and inrush current free when a locomotive enters or leaves the neutral section. Furthermore, this scheme is cost low by employing updated control strategy of software and add both the two current sensors and two connection wires of hardware.

This study investigates the moderating effect of CEO power on the relationship between labor productivity and financial performance in the Tehran Stock Exchange (TSE).

In this study, the power of the CEO variable was measured using the power index method and its effect on the relationship between labor productivity and financial performance was tested using a multivariate regression. The study sample consisted of 1,040 observations and 130 firms listed on the TSE over an eight-year period between 2012 and 2019. Panel data and appropriate statistical techniques were applied to estimate models. In this study, Tobin’s Q and return on assets (ROA) are the two variables used to measure financial performance.

The results of the hypotheses show that the link between labor productivity and financial performance based on Tobin’s Q and ROA strengthens with increasing CEO power. Thus, the stewardship theory is approved on the TSE. In addition, CEO power and labor productivity have a positive impact on firm performance.

To the best of the author’s knowledge, this is the first study to examine the moderating impact of CEO power on the relationship between labor productivity and firms' financial performance in emerging capital markets. Therefore, the results of this study can be used by investors, board of directors, policymakers and regulations.

Taking into consideration the sanctions on Iran's economy during the study period and to increase the productivity and financial performance of the company, the results of this study can provide a practical guide for the board of directors to consider the characteristics of CEO power and how to choose it in the emerging capital market. Additionally, the study results show that investors should choose companies with strong CEO to invest in the Iranian capital market.

The current study is the first study conducted in an emerging economy to examine the moderating impact of CEO power on the link between labor productivity and financial performance.

Downward line extension is a valuable growth strategy that enables multiple products and services to meet diverse customer needs. However, downward extended products launched by high-status brands may be challenged by horizontal extended products launched by relatively low-status brands when these two types of products target similar consumers. This study aims to examine the impact of product type (horizontal extended versus downward extended) on consumers’ purchase intentions, the underlying mechanism and the moderating role of power distance belief.

Four scenario-based experiments were conducted to probe the research questions.

Consumers develop lower purchase intentions for downward (versus horizontal) extended products due to the reduction of perceived fit and self-congruity (Study 1). Beyond that, power distance belief moderates the impact of product type on consumers’ purchase intentions, as a low power distance belief reduces the negative effect of downward line extension (Studies 2a, 2b and 2c). Perceived fit and self-congruity mediate the interaction effect between product type and power distance belief on consumers’ purchase intentions (Study 2c).

This study provides marketing practitioners with guidance on implementing the strategy of downward line extension.

This study serves as a preliminary effort to compare consumers’ responses between downward and horizontal extended products, which deepens the understanding of downward line extension. It also contributes to the body of knowledge about line extension and power distance belief by demonstrating the moderating role of power distance belief in a line extension context.

This study presents the results of a field research designed to assess the seven bases of supervisory influence over respondents in industrial organisations working in Saudi Arabia. These seven bases of influence are: referent, experience, reward, coercive, legitimate, connection and information. The sample is composed of Saudi subjects as well as non‐Saudi subjects. The respondents ranked the seven methods of influence according to their importance. Results pertaining to factor analysis indicate that culture can decide the significance of an influence method over another. This points to the fact that Saudi participants and non‐Saudi participants have different sets of power bases.

Existing control circuits for piezoelectric energy harvesting (PEH) suffers from long startup time or high power consumption. This paper aims to design an ultra-low power control circuit that can harvest weak ambient vibrational energy on the order of several microwatts to power heavy loads such as wireless sensors.

A self-powered control circuit is proposed, functioning for very brief periods at the maximum power point, resulting in a low duty cycle. The circuit can start to function at low input power thresholds and can promptly achieve optimal operating conditions when cold-starting. The circuit is designed to be able to operate without stable DC power supply and powered by the piezoelectric transducers.

When using the series-synchronized switch harvesting on inductor circuit with a large 1 mF energy storage capacitor, the proposed circuit can perform 322% better than the standard energy harvesting circuit in terms of energy harvested. This control circuit can also achieve an ultra-low consumption of 0.3 µW, as well as capable of cold-starting with input power as low as 5.78 µW.

The intermittent control strategy proposed in this paper can drastically reduce power consumption of the control circuit. Without dedicated cold-start modules and DC auxiliary supply, the circuit can achieve optimal efficiency within one input cycle, if the input signal is larger than voltage threshold. The proposed control strategy is especially favorable for harvesting energy from natural vibrations and can be a promising solution for other PEH circuits as well.

There is a worldwide need to amplify the usage of renewable energy in the manufacture of electrical energy. Thus, the integrated energy systems (IESs) have become a major part of today’s power systems. Wind and solar energies are intermittent power sources and may lead to voltage and power flow instabilities. The purpose of this paper is to use the interline power flow controller (IPFC) for limiting the overloading of the transmission lines and improving the voltage stability of the IES.

This paper deals with an integrated system consisting of wind and solar energies and conventional systems. An appropriate position for the IPFC in the IES is proposed based on the disparity line utilization factor. The IPFC is then tuned for decreasing the loss of power and lessening the voltage deviation using the grey wolf algorithm.

The method is implemented on a modified IEEE 30-bus system. Results from the study show that the mega volt ampere (MVA) loading of the overloaded lines is reduced for the IES. Also, the voltage stability and the voltage profile of the system are improved to a major extent. The real and reactive power loss of the system is also brought down.

The use of renewable energy sources is a need of the present world to overcome environmental problems. This research focuses on the use of flexible AC transmission system (FACTS) devices with renewable sources incorporated in the power system. Very limited research has been done in this field. The IPFC, which is one of the most advanced FACTS device, is used for the study.

Builds on work in organisational buying. Examines the relationship between power bases and influence strategies in an organisational buying situation, specifically, the decision to purchase the services of an advertising agency. Hypothesises the influence strategies of consultation, coalition, legitimating pressure, exchange, rational persuasion, inspirational appeals and personal appeals, related to source characteristics (power bases). Findings from 150 organisational buying decisions support findings from a recent study in the USA. Suggests that the use of an influence strategy is positively related to the corresponding type of power.

The purpose of this paper is to discuss medium‐power amplifier (MPA) design using parasitic‐aware core‐based approach.

This paper discusses a core‐based design approach, which can also deliver multi‐band radio frequency integrated circuit.

A fabricated 3.5 GHz MPA achieved a P1dB of 16.81 dBm, power‐added efficiency (PAE) of 16.74 percent and gain of 6.81 dB at the 10 dBm of input power under a low‐power supply of 3 V. The maximum current, I_max is 80.7 mA and the power consumption of the device is 242.10 mW. A fabricated 2.4 GHz MPA achieved a P1dB of 14.83 dBm, PAE of 11.73 percent and gain of 9.83 dB at the 5.0 dBm of input power under a low‐power supply of 3.0 V. The maximum current, I_max is 84.4 mA and the power consumption for this device is 253.20 mW.

This paper shows the merits of the parasitic‐aware design methods used in designing the core circuit.

Drawing from the literature on channels of distribution, four hypotheses concerning the relationships between power, satisfaction and conflict are developed. These hypotheses are tested using data from the channel of distribution for bulk beer. Finally, the causal model underlying the hypotheses is tested, using causal path analysis and an alternative causal model is presented which provides a better fit with the data and which also helps to explain some troublesome findings from previous research.

The purpose of this paper is to reveal the multi‐scale relation between power law distribution and correlation of stock returns and to figure out the determinants underlying capital markets.

The multi‐scale relation between power law distribution and correlation is investigated by comparing the original series with the special series. The eliminating intraday trend series approach developed by Liu et al. is utilized to analyze the effects of power law decay change on correlation properties, and shuffling series originated by Viswanathan et al. for the impacts of special type of correlation on power‐law distribution.

It is found that the accelerating decay of power law has an insignificant effect on correlation properties of returns and the empirical results indicate that time scale may also be an important factor maintaining power law property of returns besides correlation. When time scale is under critical point, the effects of correlation are crucial, and the correlation of nonlinear long‐range presents the strongest influence. However, for time scale beyond critical point, the impact of correlation begins to diminish or even finally disappear and then the power law property shows complete dependence on time scale.

The 5‐min high frequency data of the Shanghai market as the empirical benchmark is insufficient to depict the relation over the entire time scale in the Chinese stock market.

The paper identifies the determinants of market dynamics to apply them to risk management through analysis of multi‐scale relations, and supports endeavors to introduce time parameter into further risk measures and control.

The paper provides the empirical evidence that time scale is one of the key determinants of market dynamics by analyzing the multi‐scale relation between power law distribution and correlation.