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The purpose of this article is to treat the nonlinear optimal control problem in EV traction systems which are based on 5-phase induction motors. Five-phase permanent magnet synchronous motors and five-phase asynchronous induction motors (IMs) are among the types of multiphase motors one can consider for the traction system of electric vehicles (EVs). By distributing the required power in a large number of phases, the power load of each individual phase is reduced. The cumulative rates of power in multiphase machines can be raised without stressing the connected converters. Multiphase motors are also fault tolerant because such machines remain functional even if failures affect certain phases.

A novel nonlinear optimal control approach has been developed for five-phase IMs. The dynamic model of the five-phase IM undergoes approximate linearization using Taylor series expansion and the computation of the associated Jacobian matrices. The linearization takes place at each sampling instance. For the linearized model of the motor, an H-infinity feedback controller is designed. This controller achieves the solution of the optimal control problem under model uncertainty and disturbances.

To select the feedback gains of the nonlinear optimal (H-infinity) controller, an algebraic Riccati equation has to be solved repetitively at each time-step of the control method. The global stability properties of the control loop are demonstrated through Lyapunov analysis. Under moderate conditions, the global asymptotic stability properties of the control scheme are proven. The proposed nonlinear optimal control method achieves fast and accurate tracking of reference setpoints under moderate variations of the control inputs.

Comparing to other nonlinear control methods that one could have considered for five-phase IMs, the presented nonlinear optimal (H-infinity) control approach avoids complicated state-space model transformations, is of proven global stability and its use does not require the model of the motor to be brought into a specific state-space form. The nonlinear optimal control method has clear implementation stages and moderate computational effort.

In the transportation sector, there is progressive transition to EVs. The use of five-phase IMs in EVs exhibits specific advantages, by achieving a more balanced distribution of power in the multiple phases of the motor and by providing fault tolerance. The study’s nonlinear optimal control method for five-phase IMs enables high performance for such motors and their efficient use in the traction system of EVs.

Nonlinear optimal control for five-phase IMs supports the deployment of their use in EVs. Therefore, it contributes to the net-zero objective that aims at eliminating the emission of harmful exhaust gases coming from human activities. Most known manufacturers of vehicles have shifted to the production of all-electric cars. The study’s findings can optimize the traction system of EVs thus also contributing to the growth of the EV industry.

The proposed nonlinear optimal control method is novel comparing to past attempts for solving the optimal control problem for nonlinear dynamical systems. It uses a novel approach for selecting the linearization points and a new Riccati equation for computing the feedback gains of the controller. The nonlinear optimal control method is applicable to a wider class of dynamical systems than approaches based on the solution of state-dependent Riccati equations.

New technologies have provided new tools we may use as finance professors to communicate with our students. Instant messaging (IM) has become a common communication tool in industry and among students. The purpose of this paper is to investigate the use of IM as a communication tool in finance courses.

After reviewing the advantages and disadvantages of IM, the students were surveyed to determine how they viewed IM in comparison to other communication techniques.

The paper finds that 50 per cent or students use IM at any time (not just for class). The majority of the IM users, use it several times a day and have used it for two to three years. Only about 15.7 per cent of our students have used IM for our classes. The range of IM usage in the classes is 7‐25 per cent. Of those students who have used IM for our courses, they have used it 2‐5 times during the semester and almost all students found it useful. Students were asked to rate various methods of professor/student communication. The students strongly like face‐to‐face communication, followed by (in order of preference) email, IM, and telephone. Students disagree with the statement that IM is a substitute for face‐to‐face interaction and agree that IM is a supplement to face‐to‐face interaction.

The findings suggest ways to improve communications with students and other persons.

The purpose of this paper is to make a quantitative comparison between induction machine (IM) and interior permanent magnet machine (IPM) for electric vehicle applications, in terms of electromagnetic performance and material cost.

The analysis of IM is based on an analytical method, which has been validated by test. The analysis of IPM is based on finite element analysis. The popular Toyota Prius 2010 IPM is adopted directly, and the IM is designed with the same stator outer diameter and stack length as Prius 2010 IPM for a fair comparison.

The torque capability of IM is lower than IPM for low electric loading and competitive to IPM for high electric loading. The maximum torque/power-speed characteristic of IM is competitive to IPM; while the rated torque/power-speed characteristic of IM is poorer than IPM. The power factor of IM is competitive and even better than IPM for high electric loading in low-speed region. The torque ripple of IM is comparable to IPM for high electric loading and much lower than IPM for low electric loading. The overall efficiency of IM is lower than IPM, and the maximum efficiency of copper squirrel cage IM is approximately 2-3 percent lower than IPM. The material cost of IM is about half of IPM when IM and IPM are designed with the same stator outer diameter and stack length.

The electromagnetic performances and material costs of IM and IPM are quantitatively compared and discussed.

The purpose of this paper is to provide guidelines for entrepreneurs for implementing effective inventory management (IM) practices and presents the results of a survey of machine tool enterprises in Bangalore, India.

A descriptive analysis is used to present aspects of the findings, which reflect the current state of IM in machine tool enterprises. In addition, percentages, bar diagrams and correlation analysis provide a more accurate assessment of this industry sector.

The study identified several major problems in the context of IM in machine tool enterprises including the use of rule‐of‐thumb for IM, a low importance given to forecasting, random ordering of materials, low levels of training and development, and low computer use as well as a low importance given to purchasing and variable lead‐time. The study confirmed the need for managers in the machine tool sector to alter drastically their approach to IM.

This study of 40 SMEs in Bangalore should be extended using a larger sample representative of Indian SMEs in order to arrive at findings that are more generalizable across the machine tool sector in India.

The managers of SMEs should consider seriously IM as a strategic concept simply because effective IM positively influences productivity. There is profound scope for improving the operations and performance of SMEs through the application of quality practices in IM.

Considering the lack of studies about IM in the context of Indian small and medium sized enterprises (SMEs), this paper helps fill a gap in the literature. A review of the policy framework concerned with SMEs suggests that policymakers do not consider critically the role of IM and related issues. It is significant to note that there is no exclusive reference to improvement in IM within the policy documents. At the same time, the literature review suggests that effective approaches to IM can improve the productivity and competitiveness of SMEs.

To identify controls that can harness the power and capabilities of instant messengers (IM) while minimizing potential security risks.

A risk analysis method and (CIS)² model are used.

IM is a great tool for enterprise productivity. However, it has so many risks, but one could identify and control these risks with technical and managerial countermeasures.

This paper fails to provide detailed and specific risks of commercial IMs, and the case study provided in this paper focuses on the technical rather than managerial issues.

A very helpful case study which provides general risks and controls of recent IMs for the security officers of various organizations.

This paper outlined the risks of IM and potential controls for securing public IM in the workplace.

The purpose of this study is to look at the structure of the interactions between the board of directors’ chairman qualities such as chairman independence, tenure, ethnicity, age- and impression management (IM).

The research population consists of non-financial Malaysian companies listed on Bursa Malaysia’s Main Market, using data gathered via annual reports and DataStream. The study relies on the ordinary least square regression to test the direct relationships between the directors’ chairman characteristics and IM. Moreover, robustness and sensitivity tests were used to examine the effectiveness of chairman characteristics with IM. Furthermore, the results rely on the FGLS regression as an additional test. The study found that chairman independence, chairman ethnicity and chairman age have a significant impact on IM.

The results reveal that chairman independence has a negative association with qualitative IM (IMSC1). Moreover, chairman ethnicity has a positively significant relationship with qualitative IM (IMSC1) and quantitative IM (IMSC2). Also, the effectiveness of chairman characteristics has a negative and significant association with IMSC1.

The primary goal of this paper is to fill a gap in the literature and to open up opportunities for more in-depth research on the subject. So far, there has been no research into the impact of the board chairman’s (BC) personality on IM. This study serves as a warning to policymakers, businesses and their stakeholders, as well as researchers, about the importance of BC characteristics, which may impede the effectiveness of corporate governance mechanisms. The paper provides a framework for investigating these characteristics in the context of IM.

High-stake crime investigations include cases such as murder and rape. The purpose of this paper is to outline the components of an interview strategy for suspects. In the UK, these interviews are often managed by Interview Managers who are tasked with developing effective interview strategies with the aim of ensuring all parties involved in the interview process are dealt with ethically and legally using research-based methods.

This practitioner paper is based on the experience of the authors who have provided advice and support during high-stake crime investigations both nationally and internationally using the research-base to underpin their practical advice.

To be effective, a suspect strategy constructed by an Interview Manager in high-stake crime investigations should be designed within a framework that covers the provision of strategic advice on research-based interview processes including: co-ordination of the interview process, monitoring of the interview process and evaluation of the interview process.

To ensure interviews are effectively managed during high-stake crime investigations, the suspect interview strategy must be developed to a professional standard to allow for quality assurance and outside scrutiny.

To the best of the authors’ knowledge, this is the first published paper that outlines the nature of a suspect strategy that is based on a Framework consistent with elements of the UK National Occupational Standards.

Drawing upon theories of ethical ideologies (idealism and relativism) and work locus of control, this study aims to examine how ethical ideology in job seekers influences their use of deceptive impression management (deceptive IM) behavior during job interviews.

A time-lagged study was conducted with two measurement waves to test our hypotheses. AMOS-SEM, which included bootstrapping (5,000 re-sampling) procedures to analyze the data, was used.

Results indicate that a job seeker's relativistic ethical ideology influences their use of deceptive IM behavior during job interviews and work locus of control – internal [WLOC (internal)] mediates this relationship. Exploring the relationship between ethical ideologies of job seekers and their deceptive IM behavior at job interviews, this study found that relativistic individuals with WLOC (internal) were more inclined to engage in deceptive IM.

To the best of the authors’ knowledge, this is one of the first studies to explore the role of ethical ideology in influencing deception IM behavior during job interviews. Knowledge of the relationship between job seekers ethical ideologies and deception IM behavior at job interviews would alert HR managers to adopt additional screening processes to detect candidates who indulge in deceptive IM behavior to exaggerate their image to influence the interviewer's perception.

This study attempts to examine the performance differences between firms with and without integrated management systems (IMSs), and the impact of three integration strategies (i.e. implementing quality management system (QMS) first, then environmental management system (EMS) (QMS + EMS); implementing EMS first, then QMS (EMS + QMS); implementing QMS and EMS simultaneously (QMS − EMS)) on firm performance to reveal the IMS–performance relationship and provide empirical evidence.

Two panel datasets were collected during 2009–2019. This study used the Mann–Whitney non-parametric test and a sample of 33,155 observations from 4,316 Chinese listed firms to compare the performance differences between the IMS and non-IMS groups through performance indicators. This study also examined the effects of three integration strategies on firm performance using a cross-sectional time-series feasible generalized least squares (FGLS) regression model and a sample of 11,289 observations from 2,037 firms.

The results show that significant performance differences exist between IMS and non-IMS firms; however, the performance of firms with an IMS is not always better than that of firms without IMS. Furthermore, the simultaneous integration strategy has a positive impact, whereas sequential integration strategies (QMS + EMS and EMS + QMS) negatively affect firm performance. Compared with the EMS + QMS strategies, the QMS + EMS strategies have a more prominent effect on firm performance. Simultaneous strategies are more effective than sequential strategies.

Firms should fully consider the potential benefits and costs associated with the difficulties of IMS implementation and the implementation order of different management systems and the potential effects of the management systems in different conditions. Firms also should try to develop internal capabilities through implementing different integration strategies.

By comparing performance differences between firms with and without IMS, this study enriches the understanding of the performance benefits of IMS implementation in the Chinese context. By examining the impact of integration strategies that follow different sequences on firm performance, this study promotes an in-depth understanding of the integration strategies and their performance implications beyond simple descriptions and also provides new insights into operations strategy models.

The concept of corporate social responsibility of the enterprise covers a vast territory! This paper proposes to limit the analysis and evaluation of this concept to three distinct aspects. The first will treat the comparatively new and evolving common law implied term in corporated into the contract of employment relating to the enterprise’s social responsibility of respect towards the employee. The second will analyse an other generically linked recent common law development in the field of the enterprise’s social responsibility of respect towards the employee, namely the implied over‐riding term. Thirdly, the novel and developing wider concept of corporate social responsibility will be addressed and assessed. Some concluding thoughts will follow.