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The purpose of this paper is to present optimization of a single-phase capacitor induction motor with respect to efficiency and starting torque by using surrogate field-circuit model for steady-state. As variables, dimensions of the rotor slots and capacitor capacitance were assumed, whereas outputs were the motor performance characteristics. Searching for a motor design of maximum starting torque or maximum efficiency were objectives of the optimization. To verify design solutions, rated load and locked rotor tests of the optimized motors were performed by computer simulation which confirmed better performance parameters of the optimized motors.

The paper presents optimization procedure of a single-phase capacitor induction motor by applying response surface methodology for surrogate 2D field-circuit model of the motor. For solving the problem a single-objective and bi-objective approach were applied.

The carried out calculations showed that obtained new structures of the capacitor induction motor have better starting properties – the higher ratio of starting to rated torque. It was also obtained the motor construction with higher efficiency and lower stator current at the same time.

The main advantage of the formulated optimization procedure was application of the SSO (sequential surrogate optimization) algorithm which exploits a polynomial surrogate model and genetic algorithm to find minimum of the objective functions and also to speed up computations.

This study aims to answer the question whether investment funds managers exhibit behavioural biases in their investment decisions. Furthermore, it investigates if fund managers, as a group of institutional investors, make decisions in response to central bank’s communication as well as other information in relation to various behavioural inclinations.

A comprehensive study was conducted based on a questionnaire, which is composed of three main parts exploring: (1) general information about the funds under the management of the surveyed group of fund managers, (2) factors that influence the investment process with an emphasis on the National Bank of Poland communication and (3) behavioural inclinations of the surveyed group. Cronbach’s alpha statistic was applied for measuring the reliability of the survey questionnaire and then chi-squared test was used to investigate the relationships between the answers provided in the survey.

The central bank’s communication matters for investors, but its impact on their decisions appears to be only moderate. Interest rates were found to be the most important announcements for investment fund managers. The stock market was the most popular market segment where the investments were made. The ultra-short time horizon played no, or only small, role in the surveyed fund managers’ decisions as most of them invested in a longer horizon covering 1 to 5 years. Moreover, most respondents declared that they considered in their decisions the information about market expectations published in the media. Finally, majority of the fund managers manifested limited rationality and were subject to behavioural biases, but the decisions and behavioural inclinations were independent and, in most cases, they did not influence each other.

The results reported in this study can be used in practice to better understand and to improve the fund managers’ decision-making processes.

Apart from the commonly tested behavioural biases in the group of institutional investors in the existing literature, such as loss aversion, disposition effect or overconfidence, this paper also focuses on the less intensively analysed behavioural inclinations, i.e. framing, illusion of the control, representativeness, sunk cost effect and fast thinking. The originality of this study further lies in the way the research was conducted through interviews with fund managers, who were found to be subject to behavioural biases, although those behavioural inclinations did not influence their investment decisions. This finding indicates that professionalism and collectivism in the group of institutional investors protect them from irrationality.

Across the globe, every organization is striving to enhance the productivity and growth rate, but the prosperity and success of an organization is determined by the type of work environment in which it operates. To address this apprehension, this paper aims to determine the effect of toxic workplace environment on job stress that can badly affect the job productivity of an employee.

As an independent variable, toxic workplace environment was used as a complete spectrum consisting multiple dimensions named as workplace ostracism, workplace incivility, workplace harassment and workplace bullying. Job stress was used as a mediating variable between the spectrum of toxic workplace environment and job productivity. In this regard, self-administered close-ended questionnaire was used to collect the data from 267 employees of the health sector (HS) of Lahore region in Pakistan. For analysis purpose, we used confirmatory factor analysis to ensure the convergent and discriminant validity of the factors. AMOS 22 was used to check the direct and indirect effect of selected variables. Hayes mediation approach was used to check the mediating role of job stress between four dimensions of toxic workplace environment and job productivity.

The output demonstrated that the dimensions of toxic workplace environment have a negative significant relationship with job productivity, while job stress was proved as a statistical significant mediator between dimensions of toxic workplace environment and job productivity. Finally, we conclude that organizations need to combat/cleanse the roots of toxic workplace environment to ensure their prosperity and success.

This study aims to determine the effect of toxic workplace environment on job stress that can badly affect the job productivity of an employee. An empirical study in the context of the HS of Pakistan. This study, which is based on HS, has never been reported before in literature.