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Article
Publication date: 15 June 2010

Yanhui Lai, Xiaofeng Zhang and Lizhong Song

The purpose of this paper is to overcome the shortcoming that discrete variable structure control (VSC) system trajectory oscillates in a neighborhood of the origin.

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Abstract

Purpose

The purpose of this paper is to overcome the shortcoming that discrete variable structure control (VSC) system trajectory oscillates in a neighborhood of the origin.

Design/methodology/approach

Among all the proposed reaching laws, W. Gao's theory is most perfect. It makes great progress in revealing the motion mechanism of discrete‐time VSC systems. However, it has an obvious defect, i.e. the system trajectory oscillates in a neighborhood of the origin rather than converges to the origin. So, a new reaching law named variable rate reaching law to which the stability at the origin can be expected is proposed. The special feature of this new reaching law is that it is directly proportional to the norm of the state vector and can result in a sector‐shaped switching region. On the basis of analyzing the characteristic of the variable rate and the conventional reaching laws, a new combined control algorithm that discards the shortcomings of the two reaching laws and carries on their merits is formed, so satisfactory control performance can be achieved.

Findings

A new combined reaching law control algorithm, which uses the exponential rate reaching law in the reaching mode and in the front phase of the sliding mode, and uses the variable rate reaching law in the back phase of the sliding mode and in the steady‐state mode, is formed.

Practical implications

The paper is a very useful reference for control system designers.

Originality/value

The new control strategy is applied to the controller design for a brushless DC servomotor and good control performance is obtained.

Details

Kybernetes, vol. 39 no. 6
Type: Research Article
ISSN: 0368-492X

Keywords

Article
Publication date: 23 May 2008

Paraskevas C. Argouslidis

Drawing upon theory on organizational decision speed, this study aims to take a first step toward an understanding of the temporal aspect of the elimination decision‐making…

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Abstract

Purpose

Drawing upon theory on organizational decision speed, this study aims to take a first step toward an understanding of the temporal aspect of the elimination decision‐making process in financial services (i.e. the process of withdrawing an item from the product line) and in particular of the organizational, product‐specific and environmental determinants of the speed of the elimination decision‐reaching and the elimination implementation processes.

Design/methodology/approach

Data were collected through a mail survey to a stratified random sample of 500 UK financial institutions, yielding 167 returns.

Findings

The paper finds first, the speed of elimination decision‐reaching is shaped by product line length, market orientation, formalization, technological change, and the austerity of the regulatory context. Second, the speed of the elimination implementation process is influenced by whether the item that is considered for elimination is a typical bank, insurance, or mortgage product, by its delivery method, and by whether it is for the retail or the corporate market.

Practical implications

By responding to an array of issues highlighted as important research directions by previous studies on organizational decision‐speed, this study has useful theoretical implications. The findings also provide practitioners with a first picture of how the pace of their line rationalization plans may be impeded or accelerated by a set of contextual factors.

Originality/value

The study represents the first attempt to examine the service elimination process (i.e. a marketing decision area) in relation to decision speed (i.e. a central aspect of organizational decision making). As such, it makes a clear inter‐disciplinary contribution.

Details

Journal of Services Marketing, vol. 22 no. 3
Type: Research Article
ISSN: 0887-6045

Keywords

Book part
Publication date: 5 October 2018

Nasir Bedewi Siraj, Aminah Robinson Fayek and Mohamed M. G. Elbarkouky

Most decision-making problems in construction are complex and difficult to solve, as they involve multiple criteria and multiple decision makers in addition to subjective…

Abstract

Most decision-making problems in construction are complex and difficult to solve, as they involve multiple criteria and multiple decision makers in addition to subjective uncertainties, imprecisions and vagueness surrounding the decision-making process. In many instances, the decision-making process is based on linguistic terms rather than numerical values. Hence, structured fuzzy consensus-reaching processes and fuzzy aggregation methods are instrumental in multi-criteria group decision-making (MCGDM) problems for capturing the point of view of a group of experts. This chapter outlines different fuzzy consensus-reaching processes and fuzzy aggregation methods. It presents the background of the basic theory and formulation of these processes and methods, as well as numerical examples that illustrate their theory and formulation. Application areas of fuzzy consensus reaching and fuzzy aggregation in the construction domain are identified, and an overview of previously developed frameworks for fuzzy consensus reaching and fuzzy aggregation is provided. Finally, areas for future work are presented that highlight emerging trends and the imminent needs of fuzzy consensus reaching and fuzzy aggregation in the construction domain.

Details

Fuzzy Hybrid Computing in Construction Engineering and Management
Type: Book
ISBN: 978-1-78743-868-2

Keywords

Article
Publication date: 28 January 2014

Hye-Jin Paek, Elizabeth Taylor Quilliam, Sookyong Kim, Lorraine J. Weatherspoon, Nora J. Rifon and Mira Lee

The purpose of this paper is to investigate the content of food advergames and the nutritional quality of foods promoted in those advergames with the presence of child visitors…

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Abstract

Purpose

The purpose of this paper is to investigate the content of food advergames and the nutritional quality of foods promoted in those advergames with the presence of child visitors.

Design/methodology/approach

This study integrates three different sources of data, first, characteristics of the audience from internet audience measurement metrics; second, an analysis of food advergame content; and third, an analysis of the dietary quality of the foods in advergames.

Findings

The results show that 83.2 percent of the total 143 advergames are sponsored by CFBAI participating companies and 79.5 percent of the total 44 advergames reaching children are sponsored by those companies. About 87 percent of the advergames reaching children do not include age limit specification. By contrast, about 71 percent of the advergames reaching children include ad breaks and about half of the advergames reaching children include healthy lifestyle information. Compared to the total, advergames reaching children seem to have a higher level of brand integration. Moreover, most foods that the advergames promote are classified as unhealthy. Finally, the results show that ad breaks and number of brand identifiers are the two significant predictors of food advergames with child unique visitors.

Originality/value

Despite the increased attention to and scrutiny of innovative and interactive food marketing targeting children, little is known about the extent to which such techniques actually reach children, nor about the content and nutritional quality of foods they promote. This study attempts to fill in the gap by focussing on food advergames.

Details

Internet Research, vol. 24 no. 1
Type: Research Article
ISSN: 1066-2243

Keywords

Article
Publication date: 8 March 2010

José González, Wenwei Yu and Alejandro Hernandez Arieta

It is widely agreed that amputees have to rely on visual input to monitor and control the position of the prosthesis while reaching and grasping because of the lack of…

Abstract

Purpose

It is widely agreed that amputees have to rely on visual input to monitor and control the position of the prosthesis while reaching and grasping because of the lack of proprioceptive feedback. Therefore, visual information has been a prerequisite for prosthetic hand biofeedback studies. This is why, the underlying characteristics of other artificial feedback methods used to this day, such as auditive, electro‐tactile, or vibro‐tactile feedback, has not been clearly explored. The purpose of this paper is to explore whether it is possible to use audio feedback alone to convey more than one independent variable (multichannel) simultaneously, without relying on the vision, to improve the learning of a new perceptions, in this case, to learn and understand the artificial proprioception of a prosthetic hand while reaching.

Design/methodology/approach

Experiments are conducted to determine whether the audio signals could be used as a multi‐variable dynamical sensory substitution in reaching movements without relying on the visual input. Two different groups are tested, the first one uses only audio information and the second one uses only visual information to convey computer‐simulated trajectories of two fingers.

Findings

The results show that it is possible to use auditive feedback to convey artificial proprioceptive information instead of vision as a guide, thus assist users by internalizing new perceptions.

Originality/value

This way, the strong and weak points of auditive feedback can be observed and can be used to improve future feedback systems or schemes, which can integrate different feedback methods to provide more information to the user.

Details

Industrial Robot: An International Journal, vol. 37 no. 2
Type: Research Article
ISSN: 0143-991X

Keywords

Book part
Publication date: 13 November 2017

Robert Kozielski, Michał Dziekoński and Jacek Pogorzelski

It is generally recognised that companies spend approximately 50% of their marketing budget on promotional activities. Advertising belongs to the most visible areas of a company’s…

Abstract

It is generally recognised that companies spend approximately 50% of their marketing budget on promotional activities. Advertising belongs to the most visible areas of a company’s activity. Therefore, it should not be surprising that the average recipient associates marketing with advertising, competitions and leaflets about new promotions delivered to houses or offices. Advertising, especially Internet advertising, is one of the most effective forms of marketing and one of the fastest developing areas of business. New channels of communication are emerging all the time – the Internet, digital television, mobile telephony; accompanied by new forms, such as the so-called ambient media. Advertising benefits from the achievements of many fields of science, that is, psychology, sociology, statistics, medicine and economics. At the same time, it combines science and the arts – it requires both knowledge and intuition. Contemporary advertising has different forms and areas of activity; yet it is always closely linked with the operations of a company – it is a form of marketing communication.

The indices of marketing communication presented in this chapter are generally known and used not only by advertising agencies but also by the marketing departments of many organisations. Brand awareness, advertising scope and frequency, the penetration index or the response rate belong to the most widely used indices; others, like the conversion rate or the affinity index, will get increasingly more significant along with the process of professionalisation of the environment of marketing specialists in Poland and with increased pressure on measuring marketing activities. Marketing indices are used for not only planning activities, but also their evaluation; some of them, such as telemarketing, mailing and coupons, provide an extensive array of possibilities of performance evaluation.

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. 42 no. 6
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 20 February 2017

Rusmir Cimirotić, Verena Duller, Birgit Feldbauer-Durstmüller, Bernhard Gärtner and Martin R.W. Hiebl

Although the number of women working in management accounting has increased, the percentage of female executives in this area remains low. Previous studies examining the…

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Abstract

Purpose

Although the number of women working in management accounting has increased, the percentage of female executives in this area remains low. Previous studies examining the underrepresentation of women in accounting leadership positions have analyzed factors that hinder women from reaching these positions. The purpose of this paper, by contrast, is to identify factors that support the advancement of those female executives who have reached a leadership position. Further, this paper highlights the self-reported obstacles and difficulties faced by respondents in reaching their current positions.

Design/methodology/approach

Semi-structured interviews were conducted face-to-face with ten female executives in the management accounting departments of Austrian firms. The interview transcripts were analyzed by using the general inductive approach.

Findings

The results of the study show that most women classified their social skills and professional expertise as the key factors leading to their successful advancement; however, they also highlighted that ambition and luck played important roles. The authors found that support from both life partners and superiors was essential for these women in reaching their current positions and in handling difficulties when in a leadership position. Further difficulties include working time, work-life balance and motherhood.

Research limitations/implications

As the findings are based on interviews conducted with female Austrian executives in large (more than 250 employees) manufacturing- or service-sector firms, they are not readily generalizable.

Practical implications

This study identifies factors that may help prospective female management accounting executives reach leadership positions. Furthermore, less senior female management accountants may learn from this paper that women who have already reached leadership positions in management accounting may have had to cope with problems similar to those that younger and less senior female management accountants currently experience.

Originality/value

This paper is among the first to address gender in the field of management accounting.

Details

Management Research Review, vol. 40 no. 2
Type: Research Article
ISSN: 2040-8269

Keywords

Article
Publication date: 17 October 2008

Huaishu Li, Lizhong Song and Yanhui Lai

In order to improve performance robustness of control systems, the discrete variable structure control (VSC) design for uncertain systems and its application to a ship autopilot…

Abstract

Purpose

In order to improve performance robustness of control systems, the discrete variable structure control (VSC) design for uncertain systems and its application to a ship autopilot are to be discussed in this paper.

Design/methodology/approach

Discrete‐time variable structure control (DVSC) becomes worth investigating and various DVSC methods have been suggested by many papers. The approach that used the reaching law for controller design can describe how the switching function decreases toward zero and easier to obtain the control law, but this conventional method has some defects not to be ignored. First, due to the influence of the conventional discrete reaching law itself, the system trajectory oscillates in a neighborhood of the origin rather than converges to the origin. Second, this method requires that the uncertainty bound is known as a premise to assure robustness, so creates an over‐conservative controller and enlarges chattering.

Findings

It can be shown that the estimation error dynamics can be decoupled from sliding surface dynamics using the proposed scheme. Robust stability of the closed‐loop system can be ensured in the presence of uncertainties with bounded changing rate. No chattering occurs.

Practical implications

To supply useful references to controller design.

Originality/value

A new approach in the design of discrete VSC based on the reaching law approach is presented, a new discrete reaching law, which is stable at the origin, is proposed, and an algorithm for uncertainty estimation is developed in this paper. The proposed algorithm is applied to the control of a ship autopilot servo system. Simulation results show that the controller designed here can track a desired course well and exhibits very good performance robustness.

Details

Kybernetes, vol. 37 no. 9/10
Type: Research Article
ISSN: 0368-492X

Keywords

Article
Publication date: 2 September 2013

Jian Liu, Peng Liu, Sifeng Liu, Yizhong Ma and Wensheng Yang

Process mining provides a new means to improve processes in a variety of application domains. The purpose of this paper is to abstract a process model and then use the discovered…

Abstract

Purpose

Process mining provides a new means to improve processes in a variety of application domains. The purpose of this paper is to abstract a process model and then use the discovered models from process mining to make useful optimization via predictions.

Design/methodology/approach

The paper divides the process model into a combination of “pair-adjacent activities” and “pair-adjacent persons” in the event logs. First, two new handover process models based on adjacency matrix are proposed. Second, by adding the stage, frequency, and time for every activity or person into the matrix, another two new handover prediction process models based on stage adjacency matrix are further proposed. Third, compute the conditional probability from every stage to next stage through the frequency. Finally, use real data to analyze and demonstrate the practicality and effectiveness of the proposed handover optimization process.

Findings

The process model can be extended with information to predict what will actually happen, how possible to reach the next activity, who will do this activity, and the corresponding probability if there are several people executing the same activity, etc.

Originality/value

The contribution of this paper is to predict what will actually happen, how possible it is to reach the following activities or persons in the next stage, how soon to reach the following activities or persons by calculating all the possible interval time via different traces, who will do this activity, and the corresponding probability if there are several people executing the same activity, etc.

Details

Kybernetes, vol. 42 no. 7
Type: Research Article
ISSN: 0368-492X

Keywords

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