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The purpose of this study is to test the performance of the designed automatic control system based on the Linear Quadratic Regulator (LQR) and Linear Quadratic Gaussian (LQG) algorithms during landing of the helicopter on the ship deck. This paper is a further development of the series based on Topczewski et al. (2020).

The system consists of two automatic control algorithms based on LQR and the LQG. It is integrated with the ship motion prediction system based on autoregressive algorithm with parameters calculated using Burg’s method. It is assumed that the source of necessary navigation data is integrated Inertial Navigation System with Global Positioning System. Landing of the helicopter on the ship deck is performed in automatic way, based on the preselected procedure. Performance of the control system is analyzed when all necessary navigation data is available for the system and in case when one of the parameters is unavailable during performing the procedure.

In this paper, description of the designed control system developed for performing the approach and landing of the helicopter using selected procedure is presented. Helicopter dynamic model is validated using the manufacturer data and by test pilots, overview is presented. Necessary information about ship motion model is also included. Tests showing mission performance while using LQR and LQG algorithms applied to the control system are presented and analyzed, taking into account both situations when full navigation data is available/unavailable for the control system.

Results of the system performance analyses can be used for selection of the proper control methodology for prospective helicopters autopilots. Furthermore, the system can be used to analyze the mission safety when information about one of the navigation parameters is identified by the navigation system as unavailable or incorrect and therefore unavailable during landing on the ship deck.

In this paper, control system dedicated for the automatic landing of the helicopter on the ship deck, based on two different control algorithms is presented. Influence of lack of information about one of the navigation parameters on the mission performance is analyzed.

The purpose of this paper is to test the performance of the control system developed for the helicopter automatic approach and landing on the moving vessel deck, when different values of backlashes are applied to the four control actuators.

The system consists of automatic control algorithm based on the linear quadratic regulator and the vessel motion prediction algorithm based on autoregressive method with parameters calculated using Burg’s method. Necessary navigation data is provided by on-board inertial navigation system/Global Positioning System. Calculated control commands are executed by four electromechanical actuators. Performance of the mission, which is based on selected procedure of approach and landing of the helicopter on the moving vessel deck, is analyzed taking into account different values of backlashes applied to the actuators.

In this paper, a description of the control system dedicated for automatic approach and landing of the helicopter on the moving vessel deck is shown. Necessary information about helicopter dynamic model, control system and vessel motion model is included. Tests showing influence of actuator backlashes on the mission performance are presented.

The developed control methodology can be adapted for selected helicopter and used in prospective development of an automatic flight control system (AFCS) or in a simulator. The system can be used to define in which conditions helicopter can perform safe and successful automatic approach and landing on a moving vessel deck.

In this paper, an integrated control system is presented; influence of the control actuator backlashes on the mission performance is analyzed.

The authors study how enabling perceptions (flexibility, reparability and internal and global transparency) of a budgetary control system are formed, and whether enabling perceptions empower lower-level managers and make them form less negative attitudes about red tape in the organization. This study research is warranted because of the lack of knowledge on how perceptual variation in flexibility, repairability and transparency of a control system within an organization, where managers experiencing the same control system design, can be explained.

Survey data with answers from 211 managers from a large local government organization in Sweden is analyzed with structural equation modeling.

The extent to which the budget system is perceived as having enabling qualities (being flexible, reparable and transparent) is explained by the safeness of the individual manager's psychological climate. This climate is characterized by trust and fairness perceptions in upper management. In turn, enabling perceptions positively affect a sense of psychological empowerment and reduces attitudes toward red tape in the organization.

The authors contribute by identifying an important factor explaining individual-level variability in enabling perceptions of control systems within organizations. Compared to previous research that has taken an interest in the organizational-level climate, the authors theorize about and investigate (parts of) the individual-level psychological climate as an explanation of within-system variability.

This study aims to address how the ISO 14001 standardisation and certification process improves substantive performance in small to medium-sized enterprises (SMEs) through the development of an environmental management control system (EMCS).

A qualitative cross-case interview design with those responsible for the implementation of an environmental management system (certified to ISO 14001) in SMEs is adopted to inductively “theorise” the EMCS.

The design and monitoring of environmental controls are often beyond the scope of the SMEs’ top management team and include extra-organisational dimensions such as the external audit and institutional requirements. This suggests more complex control pathways for SMEs to produce EMCS that primarily function as packages and are broader than the analytical level of the firm. Here, controlling for environmental performance exists at strategic and operational levels, as well as beyond the SMEs’ boundaries.

Various internal controls are put forward for SME owner-managers to meet environmental targets (e.g. gamification and interpersonal communication strategies). This builds upon a broader accountability perspective wherein formalised hierarchical control is only one route for ensuring sustainable action within the ISO 14001-certified SMEs.

This study contributes to a more sustainable society through developing an understanding of how environmental sustainability is substantively managed by SMEs to improve performance for current and future generations.

This paper, to the best of the author’s knowledge, is one of the first to establish how SMEs control for environmental sustainability from empirically derived evidence. In doing so, it provides an example of the EMCS for the SME context.

Internal control systems are critical to an organization's efficiency and promotes the adherence to norms and rules. The purpose of this study is to evaluate the impact of internal control systems on banking industry effectiveness.

Data were collected from 15 commercial and 20 rural banks. The hypothesized relationships were supported by the data. A structural equation modeling was applied in testing the conceptual model and hypothesis. Confirmatory factor analysis was conducted to establish validity and reliability of the dimensions.

The results show that organizational effectiveness was significantly impacted by three dimensions of internal control systems: control activities, control environments and risk assessment. However, the impact of monitoring of control on organizational effectiveness was not significant. The results also show a nonsignificant impact of information and communication on organizational effectiveness.

Since the current study concentrated on the banking sector with its distinct characteristics, the generalizability of the conclusions may be limited.

The study's findings may aid decision-makers and stakeholders in the adoption, designing and implementation of proactive internal control system to enhance operational efficiency, effectiveness and competitive advantage.

The study advances the literature by empirically evidencing that internal control systems impact organizational effectiveness.

This study aims to propose an offline exploratory method that consists of two stages: first, the authors focus on completing the kinematics model of the system by analyzing the Jacobians in the vicinity of the starting point and deducing a virtual input to effectively navigate the system along the non-holonomic constraint. Second, the authors explore the sensorimotor space in a predetermined pattern and obtain an approximate mapping from sensor space to chained form that facilitates controllability.

In this paper, the authors tackle the controller acquisition problem of unknown sensorimotor model in non-holonomic driftless systems. This feature is interesting to simplify and speed up the process of setting up industrial mobile robots with feedback controllers.

The authors validate the approach for the test case of the unicycle by controlling the system with time-state control policy. The authors present simulated and experimental results that show the effectiveness of the proposed method, and a comparison with the proximal policy optimization algorithm.

This research indicates clearly that feedback control of non-holonomic systems with uncertain kinematics and unknown sensor configuration is possible.

This study aims at investigating the extent of SysTrust’s framework (principles and criteria) as an internal control approach for assuring the reliability of accounting information system (AIS) were being implemented in Jordanian business organizations.

The study is based on primary data collected through a structured questionnaire from 239 out of 328 shareholdings companies. The survey units were the shareholding companies in Jordan, and the single key respondents approach was adopted. The extents of SysTrust principles were also measured. Previously validated instruments were used where required. The data were analysed using t-test and ANOVA.

The results indicated that the extent of SysTrust being implemented could be considered to be moderate at this stage. This implies that there are some variations among business organizations in terms of their level of implementing of SysTrust principles and criteria. The results also showed that the extent of SysTrust principles being implemented was varied among business organizations based on their business sector. However, there were not found varied due to their size of business and a length of time in business (experience).

This study is only conducted in Jordan as a developing country. Although Jordan is a valid indicator of prevalent factors in the wider MENA region and developing countries, the lack of external validity of this research means that any generalization of the research findings should be made with caution. Future research can be orientated to other national and cultural settings and compared with the results of this study.

The study provides evidence of the need for management to recognize the importance of the implementation of SysTrust principles and criteria as an internal control for assuring the reliability of AIS within their organizations and be aware which of these principles are appropriate to their size and industry sector.

The findings would be valuable for academic researchers, managers and professional accounting to acquire a better undemanding of the current status of the implementation of the SysTrust principles (i.e., availability, security, integrity processing, confidentiality, and privacy) as an internal control method for assuring the reliability of AIS by testing the phenomenon in Jordan as a developing country.

Steer-by-wire (SBW) system mainly relies on sensors, controllers and motors to replace the traditionally mechanical transmission mechanism to realize steering functions. However, the sensors in the SBW system are particularly vulnerable to external influences, which can cause systemic faults, leading to poor steering performance and even system instability. Therefore, this paper aims to adopt a fault-tolerant control method to solve the safety problem of the SBW system caused by sensors failure.

This paper proposes an active fault-tolerant control framework to deal with sensors failure in the SBW system by hierarchically introducing fault observer, fault estimator, fault reconstructor. Firstly, the fault observer is used to obtain the observation output of the SBW system and then obtain the residual between the observation output and the SBW system output. And then judge whether the SBW system fails according to the residual. Secondly, dependent on the residual obtained by the fault observer, a fault estimator is designed using bounded real lemma and regional pole configuration to estimate the amplitude and time-varying characteristics of the faulty sensor. Eventually, a fault reconstructor is designed based on the estimation value of sensors fault obtained by the fault estimator and SBW system output to tolerate the faulty sensor.

The numerical analysis shows that the fault observer can be rapidly activated to detect the fault while the sensors fault occurs. Moreover, the estimation accuracy of the fault estimator can reach to 98%, and the fault reconstructor can make the faulty SBW system to retain the steering characteristics, comparing to those of the fault-free SBW system. In addition, it was verified for the feasibility and effectiveness of the proposed control framework.

As the SBW fault diagnosis and fault-tolerant control in this paper only carry out numerical simulation research on sensors faults in matrix and laboratory/Simulink, the subsequent hardware in the loop test is needed for further verification.

Aiming at the SBW system with parameter perturbation and sensors failure, this paper proposes an active fault-tolerant control framework, which integrates fault observer, fault estimator and fault reconstructor so that the steering performance of SBW system with sensors faults is basically consistent with that of the fault-free SBW system.

In recent years, owing to the rapidly increasing labor costs, the demand for robots in daily services and industrial operations has been increased significantly. For further applications and human–robot interaction in an unstructured open environment, fast and accurate tracking and strong disturbance rejection ability are required. However, utilizing a conventional controller can make it difficult for the robot to meet these demands, and when a robot is required to perform at a high-speed and large range of motion, conventional controllers may not perform effectively or even lead to the instability.

The main idea is to develop the control law by combining the SMC feedback with the ADRC control architecture to improve the robustness and control quality of a conventional SMC controller. The problem is formulated and solved in the framework of ADRC. For better estimation and control performance, a generalized proportional integral observer (GPIO) technique is employed to estimate and compensate for unmodeled dynamics and other unknown time-varying disturbances. And benefiting from the usage of GPIO, a new SMC law can be designed by synthesizing the estimation and its history.

The employed methodology introduced a significant improvement in handling the uncertainties of the system parameters without compromising the nominal system control quality and intuitiveness of the conventional ADRC design. First, the proposed method combines the advantages of the ADRC and SMC method, which achieved the best tracking performance among these controllers. Second, the proposed controller is sufficiently robust to various disturbances and results in smaller tracking errors. Third, the proposed control method is insensitive to control parameters which indicates a good application potential.

High-performance robot tracking control is the basis for further robot applications in open environments and human–robot interfaces, which require high tracking accuracy and strong disturbance rejection. However, both the varied dynamics of the system and rapidly changing nonlinear coupling characteristic significantly increase the control difficulty. The proposed method gives a new replacement of PID controller in robot systems, which does not require an accurate dynamic system model, is insensitive to control parameters and can perform promisingly for response rapidity and steady-state accuracy, as well as in the presence of strong unknown disturbances.

The implementation of control systems allows marketing managers to improve operational decisions and organizational results. This paper aims to identify the relationship between control combinations and organizational results and analyze the relationships between the variables attributed to the marketing managers and with marketing control combinations. Decisions involving marketing control combine formal and informal mechanisms and generate control systems that have a favorable relationship with organizational results.

The paper is based on 301 cross-sectional surveys among marketing managers. The classification procedure based on metric distance was implemented to identify the marketing control combinations. A hierarchical cluster analysis was carried out with perceptions about formal and informal control, to validate the control combination classifications. Finally, a discriminant analysis and ANOVA test were carried out for exploring factors associated with the managers. The data analysis was supported by IBM SPSS Statistics 24 software.

The authors found evidence that, when managers perceive high-control systems, the perception of non-financial and financial results is always better, but the presence of high-clan control also returns optimal results. In addition, the manager's satisfaction levels and work motivation are higher with high control systems than with other control systems.

This study contributes to the existing knowledge by providing a broader empirical basis to extend conceptual frameworks about marketing control combinations that emerge in practice.

企業設置營銷控制系統來進行營銷控制,這可讓市場經理能改善其營運決策和組織成果。本文擬確定控制合併與組織成果的關係;本文亦擬分析涉及市場經理的變數與營銷控制合併的關係。涉及營銷控制的決策會結合正式和非正式的機制,而這些決策會帶來與組織成果有良性關係的控制系統。

本研究乃基於對市場經理進行的301項橫斷調查。研究人員實施基於度量距離的分類程式,來確定營銷控制合併;為了證實有關的控制合併分類是正確的,研究人員就對正式控制和非正式控制的觀感和看法、進行了階層式分群法分析;最後,研究人員進行了判別分析和變異數分析 (ANOVA), 以探索與經理有關聯的因素。有關的數據分析得到IBM公司的SPSS (統計產品與服務解決方案) Statistics 24 (統計軟體) 的支持。

我們證實了、若主管感知高控制的系統,其對非財務結果和財務結果的看法必會較好的,但高社群控制亦會帶來最佳的結果。我們亦證實了高控制系統,較其它控制系統,更能提高主管的滿意程度和工作動機。

本研究提供了一個更廣闊的經驗基礎,以擴展涉及在實踐中出現的營銷控制合併的概念框架,就此,本研究豐富了這方面的知識。