Correction to: Towards Intelligent Interactive Theatre: Drama Management as a Way of Handling Performance

Background: Although research shows that almost all listed companies have corporate websites with dedicated investor relations (IR) sections that enable companies to ‘push’ information to investors, it was argued that such an asymmetrical approach to communication is insufficient for companies wishing to exercise good IR. The purpose of this study was to test the effectiveness of the Internet to act as a mechanism to achieve more interactive communication between companies and investors.Objectives: The objectives of the study were to measure the responsiveness, timeliness and relevance of companies’ responses to e-mail requests, and to test for the determinants (size, market-to-book ratio, profitability, leverage and liquidity) thereof.Method: The mystery investor approach and a content analysis were used to study the e-mail handling performance of companies. The associations between company-specific characteristics were statistically tested.Results: It was found that the e-mail handling performance of companies in this study was poor compared with previous studies. Significant relationships between company size and responsiveness and relevance, and between market-to-book ratio and relevance were reported, as well as between the contact method used to request information and relevance and the use of social media and timeliness.Conclusion: Specific areas where companies could improve their investor communications were identified. The need for further research was discussed to explain some of the relationships found, as well as those not found, in contrast to what was expected. Future research is warranted to examine the relationship between the e-mail handling performance of companies and information asymmetry and the cost of equity of companies.

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A New Torque Distribution Control for Four-Wheel Independent-Drive Electric Vehicles

Actuators ◽

10.3390/act10060122 ◽

2021 ◽

Vol 10 (6) ◽

pp. 122

Author(s):

Dejun Yin ◽

Junjie Wang ◽

Jinjian Du ◽

Gang Chen ◽

Jia-Sheng Hu

Keyword(s):

Electric Vehicles ◽

Vehicle Stability ◽

Hardware In The Loop ◽

Control Performance ◽

Torque Distribution ◽

Handling Performance ◽

Control Approach ◽

Tire Forces ◽

Yaw Moment ◽

New Distribution

Torque distribution control is a key technique for four-wheel independent-drive electric vehicles because it significantly affects vehicle stability and handling performance, especially under extreme driving conditions. This paper, which focuses on the global yaw moment generated by both the longitudinal and the lateral tire forces, proposes a new distribution control to allocate driving torques to four-wheel motors. The proposed objective function not only minimizes the longitudinal tire usage, but also make increased use of each tire to generate yaw moment and achieve a quicker yaw response. By analysis and a comparison with prior torque distribution control, the proposed control approach is shown to have better control performance in hardware-in-the-loop simulations.

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Comparison of Typical Controllers for Direct Yaw Moment Control Applied on an Electric Race Car

Vehicles ◽

10.3390/vehicles3010008 ◽

2021 ◽

Vol 3 (1) ◽

pp. 127-144

Author(s):

Andoni Medina ◽

Guillermo Bistue ◽

Angel Rubio

Keyword(s):

Handling Performance ◽

Electric Cars ◽

Control Techniques ◽

Race Car ◽

Yaw Rate ◽

Direct Yaw Moment Control ◽

Yaw Moment Control ◽

Moment Control ◽

Race Track ◽

Yaw Moment

Direct Yaw Moment Control (DYC) is an effective way to alter the behaviour of electric cars with independent drives. Controlling the torque applied to each wheel can improve the handling performance of a vehicle making it safer and faster on a race track. The state-of-the-art literature covers the comparison of various controllers (PID, LPV, LQR, SMC, etc.) using ISO manoeuvres. However, a more advanced comparison of the important characteristics of the controllers’ performance is lacking, such as the robustness of the controllers under changes in the vehicle model, steering behaviour, use of the friction circle, and, ultimately, lap time on a track. In this study, we have compared the controllers according to some of the aforementioned parameters on a modelled race car. Interestingly, best lap times are not provided by perfect neutral or close-to-neutral behaviour of the vehicle, but rather by allowing certain deviations from the target yaw rate. In addition, a modified Proportional Integral Derivative (PID) controller showed that its performance is comparable to other more complex control techniques such as Model Predictive Control (MPC).

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