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Open Access
Article
Publication date: 6 December 2022

Peiqing Li, Taiping Yang, Hao Zhang, Lijun Wang and Qipeng Li

This paper aimed a fractional-order sliding mode-based lateral lane-change control method that was proposed to improve the path-tracking accuracy of vehicle lateral motion.

Abstract

Purpose

This paper aimed a fractional-order sliding mode-based lateral lane-change control method that was proposed to improve the path-tracking accuracy of vehicle lateral motion.

Design/methodology/approach

In this paper the vehicle presighting and kinematic models were established, and a new sliding mode control isokinetic convergence law was devised based on the fractional order calculus to make the front wheel turning angle approach the desired value quickly. On this basis, a fractional gradient descent algorithm was proposed to adjust the radial basis function (RBF) neuron parameter update rules to improve the compensation speed of the neural network.

Findings

The simulation results revealed that, compared to the traditional sliding mode control strategy, the designed controller eliminated the jitter of the sliding mode control, sped up the response of the controller, reduced the overshoot of the system parameters and facilitated accurate and fast tracking of the desired path when the vehicle changed lanes at low speeds.

Originality/value

This paper combines the idea of fractional order calculus with gradient descent algorithm, proposed a fractional-order gradient descent method applied to RBF neural network and fast adjustment the position and width of neurons.

Details

Journal of Intelligent Manufacturing and Special Equipment, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2633-6596

Keywords

Article
Publication date: 6 December 2022

Xinhong Zou, Hongchang Ding and Jinhong Li

This paper aims to present a sliding mode control method based on disturbance observer (DO) for improving the reaching law of permanent magnet synchronous motor (PMSM).

Abstract

Purpose

This paper aims to present a sliding mode control method based on disturbance observer (DO) for improving the reaching law of permanent magnet synchronous motor (PMSM).

Design/methodology/approach

Aiming at the insufficiency of the traditional exponential reaching law used in sliding mode variable structure control, an exponential reaching law related to the speed error is proposed. The improved exponential reaching law can adaptively adjust the size of the constant velocity term in the reaching law according to the size of the speed error, so as to adaptively adjust the speed of the system approaching the sliding mode surface to overcome the control deviation and improve the dynamic and steady state performance. To improve the anti-interference ability of the system, a DO is proposed to observe the external disturbance of the system, and the observed value is used to compensate the system. The stability of the system is analyzed by Lyapunov theorem. The effectiveness of this method is proved by simulation and experiment.

Findings

Simulation and experiment show that the proposed method has the advantages of fast response and strong anti-interference ability.

Research limitations/implications

The proposed method cannot observe the disturbance caused by the change of internal parameters of the system.

Originality/value

A sliding mode control method for PMSM is proposed, which has good control performance. The proposed method can effectively suppress chattering, ensure fast response speed and have strong anti-interference ability. The effectiveness of the algorithm is verified by simulation and experiment.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0332-1649

Keywords

Book part
Publication date: 15 December 1998

Jarkko Niittymäki

Traffic signal control is one of the oldest application areas of fuzzy sets in transportation. In general, fuzzy control is found to be superior in complex problems with…

Abstract

Traffic signal control is one of the oldest application areas of fuzzy sets in transportation. In general, fuzzy control is found to be superior in complex problems with multi-objective decisions. In traffic signal control, several traffic flows compete for the same time and space, and different priorities are often set to different traffic flows or vehicle groups

The public transport priorities are a very important part of the effective traffic signal control. Normally, the public transport priorities are programmed by using special algorithms, which are tailor-made for each intersection. The experiences have proved that this kind of algorithms can be very effective if some compensation algorithms and the traffic-actuated control mode are used. We believe that using the fuzzified public transport priority algorithms, the measures of effectiveness of traffic signal control can be even better. In this paper, our fuzzy control algorithm of the public transport priorities will be presented.

Details

Mathematics in Transport Planning and Control
Type: Book
ISBN: 978-0-08-043430-8

Book part
Publication date: 3 September 2003

Shaoming Zou, Charles R Taylor and Er (Eric) Fang

While it is widely acknowledged that host governments play some role in framing the governance structure that is available to multinational corporations, some argue that…

Abstract

While it is widely acknowledged that host governments play some role in framing the governance structure that is available to multinational corporations, some argue that in recent years the influence of host governments on MNCs in terms of the level of ownership and control over their foreign ventures has diminished. The authors examine the degree of MNC’s control in foreign investment by presenting and testing a model of government influences on MNC’s control over its foreign market venture. Based on a survey of U.S. MNCs, the authors find that host government preference does influence MNC’s ownership control over its foreign market venture, which in turn influences its management control over the venture.

Details

Reviving Traditions in Research on International Market Entry
Type: Book
ISBN: 978-0-76231-044-9

Book part
Publication date: 2 May 2006

Kevin W. Williams

The most basic solution for monitoring position and attitude of an UA is through direct line-of-sight. Because they are usually standing outside, a pilot that maintains…

Abstract

The most basic solution for monitoring position and attitude of an UA is through direct line-of-sight. Because they are usually standing outside, a pilot that maintains direct line-of-sight with the aircraft is usually referred to as the EP, as opposed to an internal pilot (IP) who obtains position and attitude information electronically while inside of a ground control station (GCS). Flight using an EP represents the most basic solution to the problem of separating the pilot from the aircraft while still enabling the pilot to monitor the location and attitude of the aircraft. Pilot perspective is changed from an egocentric to an exocentric point of view. Maintaining visual contact with the UA, the EP can control the aircraft using a hand-held radio control box. Many of these control boxes are similar to those used by radio-controlled aircraft hobbyists and provide direct control of the flight surfaces of the aircraft through the use of joysticks on the box. Very little automation is involved in the use of such boxes, which control the flight surfaces of the aircraft.

Details

Human Factors of Remotely Operated Vehicles
Type: Book
ISBN: 978-0-76231-247-4

Abstract

Details

Circular Economy in Developed and Developing Countries: Perspective, Methods and Examples
Type: Book
ISBN: 978-1-78973-982-4

Article
Publication date: 30 November 2022

Ruchi Moolchandani and Sujata Kar

This paper examines whether family control exerts any influence on corporate cash holdings in Indian listed firms. It also examines how this accumulated cash of family…

Abstract

Purpose

This paper examines whether family control exerts any influence on corporate cash holdings in Indian listed firms. It also examines how this accumulated cash of family firms impacts firm value.

Design/methodology/approach

The study uses dynamic panel data regression estimated using two-step system generalized method of moments (GMM) on S&P BSE 500 firms during 2009–2018 for testing the repercussions of family control on the cash levels of a firm. Further, fixed effects regression has been employed for the valuation analysis.

Findings

Estimation results showed that family control negatively impacts cash holdings in Indian firms. Further, the cash accumulation by family firms adversely affects the market valuation of the firm. These findings signal a principal–principal (P-P) agency conflict in Indian family firms, i.e. friction between family owners and minority shareholders' interests. Minority shareholders fear that a part of the cash reserves will be used by family members for personal benefits. Thus, they discount cash reserves in family firms.

Originality/value

The study adds to the determinants of corporate cash holdings in emerging markets. To the best of the authors’ knowledge, this is the first study from India investigating family control as a determinant of cash policy. It sheds light on the P-P agency conflict in Indian family firms. P-P agency conflict is less researched in cash holdings literature as opposed to the principal–agent managerial disputes. Also, the study uses a more comprehensive definition of family control rather than just considering the ownership as used in prior cash holding research.

Details

International Journal of Emerging Markets, vol. 17 no. 10
Type: Research Article
ISSN: 1746-8809

Keywords

Article
Publication date: 23 November 2022

Chetan Jalendra, B.K. Rout and Amol Marathe

Industrial robots are extensively used in the robotic assembly of rigid objects, whereas the assembly of flexible objects using the same robot becomes cumbersome and…

Abstract

Purpose

Industrial robots are extensively used in the robotic assembly of rigid objects, whereas the assembly of flexible objects using the same robot becomes cumbersome and challenging due to transient disturbance. The transient disturbance causes vibration in the flexible object during robotic manipulation and assembly. This is an important problem as the quick suppression of undesired vibrations reduces the cycle time and increases the efficiency of the assembly process. Thus, this study aims to propose a contactless robot vision-based real-time active vibration suppression approach to handle such a scenario.

Design/methodology/approach

A robot-assisted camera calibration method is developed to determine the extrinsic camera parameters with respect to the robot position. Thereafter, an innovative robot vision method is proposed to identify a flexible beam grasped by the robot gripper using a virtual marker and obtain the dimension, tip deflection as well as velocity of the same. To model the dynamic behaviour of the flexible beam, finite element method (FEM) is used. The measured dimensions, tip deflection and velocity of a flexible beam are fed to the FEM model to predict the maximum deflection. The difference between the maximum deflection and static deflection of the beam is used to compute the maximum error. Subsequently, the maximum error is used in the proposed predictive maximum error-based second-stage controller to send the control signal for vibration suppression. The control signal in form of trajectory is communicated to the industrial robot controller that accommodates various types of delays present in the system.

Findings

The effectiveness and robustness of the proposed controller have been validated using simulation and experimental implementation on an Asea Brown Boveri make IRB 1410 industrial robot with a standard low frame rate camera sensor. In this experiment, two metallic flexible beams of different dimensions with the same material properties have been considered. The robot vision method measures the dimension within an acceptable error limit i.e. ±3%. The controller can suppress vibration amplitude up to approximately 97% in an average time of 4.2 s and reduces the stability time up to approximately 93% while comparing with control and without control suppression time. The vibration suppression performance is also compared with the results of classical control method and some recent results available in literature.

Originality/value

The important contributions of the current work are the following: an innovative robot-assisted camera calibration method is proposed to determine the extrinsic camera parameters that eliminate the need for any reference such as a checkerboard, robotic assembly, vibration suppression, second-stage controller, camera calibration, flexible beam and robot vision; an approach for robot vision method is developed to identify the object using a virtual marker and measure its dimension grasped by the robot gripper accommodating perspective view; the developed robot vision-based controller works along with FEM model of the flexible beam to predict the tip position and helps in handling different dimensions and material types; an approach has been proposed to handle different types of delays that are part of implementation for effective suppression of vibration; proposed method uses a low frame rate and low-cost camera for the second-stage controller and the controller does not interfere with the internal controller of the industrial robot.

Details

Industrial Robot: the international journal of robotics research and application, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 28 November 2022

Hafiez Sofyani, Haslida Abu Hasan and Zakiah Saleh

This study investigates internal control implementation contribution to quality management at higher education institutions (HEIs).

Abstract

Purpose

This study investigates internal control implementation contribution to quality management at higher education institutions (HEIs).

Design/methodology/approach

This study employed a qualitative method by conducting semi-structured interviews. The research respondents (interviewees) consisted of internal auditors, HEI management members and accreditation assessors of Indonesian HEIs. A total of 15 respondents were successfully interviewed to collect the data; 12 were from different HEIs, and 3 were from the HEI accreditation board.

Findings

This study deduced that internal control implementation could contribute to HEI quality management and improvement if integrated with other control policies, such as internal quality assurance, performance measurement systems and performance-based budgeting. By doing so, internal control corroborates total quality management (TQM) implementation within HEIs since it promotes employee empowerment and supervision, reduces budget wastage, increases the achievement of budget targets on output and outcome of programs and activities, enhances strategic and integrated system practices, provides reliable information for better decision-making, and promotes effective communication and coordination and good leadership culture.

Practical implications

The current study presents beneficial suggestions for HEI management on how internal control contributes to quality management at HEIs.

Originality/value

As suggested by Chalmers et al. (2019), most studies related to internal control were conducted in profit-oriented organisation settings, i.e. companies, and focused on their impact on economic aspects, such as profitability, cost efficiency and fraud mitigation. Meanwhile, internal control-related studies in the context of non-profit-oriented organisations, such as HEIs, and their role in non-economic aspects, in this case, the quality management in HEIs, is still lacking.

Details

The TQM Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1754-2731

Keywords

Article
Publication date: 5 December 2022

Januário José Monteiro, Rogério João Lunkes and Fabricia Rosa

This study aims to analyze the influence of formal and informal controls on trust and individual creativity.

Abstract

Purpose

This study aims to analyze the influence of formal and informal controls on trust and individual creativity.

Design/methodology/approach

A survey was conducted with managers of companies listed in Brazil Stock Exchange (Brazil, Bolsa, Balcão-B3), and the final sample was 124 valid responses. The data were analyzed using structural equation modeling and fuzzy set qualitative comparative analysis (FsQCA).

Findings

The results show that the influence of informal controls (cultural and personnel controls) on individual creativity is greater than that of formal controls (action and results controls). It was also found that formal and informal controls facilitate social exchanges between managers by influencing trust. Moreover, the results confirmed the mediation of trust in the relationship between controls and individual creativity. FsQCA demonstrates that formal and informal controls are complemented and, when combined with trust, enable high individual creativity.

Originality/value

The findings contribute to the literature by demonstrating that the effective use of management controls generates greater trust and awakens creative skills in managers.

Details

Journal of Accounting & Organizational Change, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1832-5912

Keywords

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