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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.

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.

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.

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

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

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.

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

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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).

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.

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

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

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.

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.

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.

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.

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.

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.

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

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.

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.

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.

To supply useful references to controller design.

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.

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.

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.

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.

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.

Admittance control is a typical complaint control methodology. Traditionally, admittance control systems are based on a dynamical relationship described by Voigt model. By contrast, after changing connection of spring and damper, Maxwell model produces different dynamics and has shown better impact absorption performance. This paper aims to design a novel compliant control method based on Maxwell model and implement it in a robot catching scenario.

To achieve this goal, this paper proposed a Maxwell model based admittance control scheme. Considering several motion stages involved in one catching attempt, the following approaches are adopted. First, Kalman filter is used to process the position data stream acquired from motion capture system and predict the subsequent object flying trajectory. Then, a linear segments with parabolic blends reaching motion is generated to achieve time-optimal movement under kinematic and joint inherent constraints. After robot reached the desired catching point, the proposed Maxwell model based admittance controller performs such as a cushion to moderate the impact between robot end-effector and flying object.

This paper has experimentally demonstrated the feasibility and effectiveness of the proposed method. Compared with typical Voigt model based compliant catching, less object bounding away from end-effector happens and the success rate of catching has been improved.

The authors proposed a novel Maxwell model based admittance control method and demonstrated its effectiveness in a robot catching scenario. The author’s approach may inspire other related researchers and has great potential of practical usage in a widespread of robot applications.

The presence of previous awarded public-private partnership (PPP) infrastructure projects that significantly delays reaching financial close constrain the likely success of new PPP projects. However, effort at investigating financial close delays of PPP projects through empirical studies by the research community received scant attention. Thus, the purpose of this paper is to identify and assess the factors causing delays in PPP projects from reaching financial close in developing countries.

The study adopted literature review and questionnaire survey. In order to capture a broad perception, a questionnaire survey was adopted, which was administered to three different primary stakeholder categories comprised public sector authorities (i.e. ministries, department, and agencies), concessionaires, and lenders/banks already involved in PPP infrastructure projects implementation in Nigeria. The data obtained were analysed using mean score, Kruskal-Wallis test, and factor analysis.

The study revealed the mean score ranking of 39 identified causes of financial close delays in PPP projects, and the mean score values for all the identified 39 causes of financial close delays are very high. The study, through factor analysis, categorised the 39 identified causes of financial close delays into eight principal factors. The factors are: decreased bankability of PPP projects; unstable economic policy; weak financial, technical, and managerial capabilities of the concessionaires; weak public institutions; lack of creditworthiness of both the project sponsors and active partner; unfavourable economy of the host country; weak legal and unfavourable environment; and high contingent liabilities, respectively.

The identification and evaluation of the factors delaying PPP projects development from reaching financial close in a reasonable time manner would be useful for PPP primary stakeholders to develop strategies to safeguard the present and future PPP projects implementation in developing countries.

The study findings would be useful for both policymakers considering PPP projects and private investors seeking to finance PPP projects in developing countries. This study is crucial as not many empirical studies have been conducted in developing countries.