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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.

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.

Most of the 3D printing machines do not comply with the requirements of on-site, large-scale multi-story building construction. This paper aims to propose the conceptualization of a tower crane (TC)-based 3D printing controlled by artificial intelligence (AI) as the first step towards a large 3D printing development for multi-story buildings. It also aims to overcome the most important limitation of additive manufacturing in the construction industry (the build volume) by exploiting the most important machine used in the field: TCs. It assesses the technology feasibility by investigating the accuracy reached in the printing process.

The research is composed of three main steps: firstly, the TC-based 3D printing concept is defined by proposing an aero-pendulum extruder stabilized by propellers to control the trajectory during the extrusion process; secondly, an AI-based system is defined to control both the crane and the extruder toolpath by exploiting deep reinforcement learning (DRL) control approach; thirdly the proposed framework is validated by simulating the dynamical system and analysing its performance.

The TC-based 3D printer can be effectively used for additive manufacturing in the construction industry. Both the TC and its extruder can be properly controlled by an AI-based control system. The paper shows the effectiveness of the aero-pendulum extruder controlled by AI demonstrated by simulations and validation. The AI-based control system allows for reaching an acceptable tolerance with respect to the ideal trajectory compared with the system tolerance without stabilization.

In related literature, scientific investigations concerning the use of crane systems for 3D printing and AI-based systems for control are completely missing. To the best of the authors’ knowledge, the proposed research demonstrates for the first time the effectiveness of this technology conceptualized and controlled with an intelligent DRL agent.

The results provide the first step towards the development of a new additive manufacturing system for multi-storey constructions exploiting the TC-based 3D printing. The demonstration of the conceptualization feasibility and the control system opens up new possibilities to activate experimental research for companies and research centres.

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.

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.

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.

This paper aims to evaluate the usefulness of two conceptual frameworks: levers of control (LOC) (Simons, 1995) and performance management systems (PMSs) (Ferreira and Otley, 2009) for studying PM practices using a case study.

A case study method is used whereby data are collected through semi-structured interviews, examination of the group’s annual reports and internal documents.

A key finding of this study is the use of a PMS at the case company which is formally structured and with objectives, mechanisms and processes designed beyond a mere “performance measurement system.” While the case analysis indicates that most of the key components of the two frameworks are featured in the company’s PMS design, the uses of Simons’ (1995) LOC, however, are not consistent with the notion of “balance” as advocated by the model.

The evidence presented in this study is based on one large manufacturing company, and hence the findings cannot be generalized.

The findings of this study can be used in enriching the design of current proposed theoretical frameworks and also in encouraging management accounting researchers to continue the efforts of studying performance management (PM) practices.

A deeper understanding of PM practices using holistic frameworks has yet to receive more contested efforts from management accounting researchers. This paper attempts to contribute to this endeavor and fill in the gap in this area of research.

This paper aims to examine the recommendation system of the video-sharing website YouTube to study how control of users is effected on online platforms.

This paper conceptualises algorithmic systems as protocols – technological and social infrastructures that both facilitate and govern interactions between autonomous actors (Galloway and Thacker, 2004, 2007). It adopts a netnographic approach (Kozinets, 2002) to study not only the formal, technological systems of the platform but also the systems as they were made sense of, understood and enacted upon by actors. It relies both on information as revealed by the organisation itself, as well as discussions between lay users in online forums and press coverage.

The results of this study indicate that the ways in which platforms selectively facilitate interactions between users constitute a form of control. While maintaining the appearance of an open and neutral marketplace, interactions on the platform are in fact highly structured. The system relies on the surveillance of user interactions to rapidly identify and propagate marketable contents, so as to maximise user “engagement” and ad revenue. The systems place few demands or restrictions on individual users, instead control is effected in a probabilistic fashion, over the population of users as a whole, so as to, in aggregate, accomplish organisational goal.

This paper contributes to the literature on accounting and control practices in online spaces, by extending the notion of control beyond overt rankings and evaluations, to the underlying technical and social infrastructures that facilitate and shape interactions.

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.