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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 propose an adaptive fractional-order sliding mode controller to solve the problem of train speed tracking control and position interval control under disturbance environment in moving block system, so as to improve the tracking efficiency and collision avoidance performance.

The mathematical model of information interaction between trains is established based on algebraic graph theory, so that the train can obtain the state information of adjacent trains, and then realize the distributed cooperative control of each train. In the controller design, the sliding mode control and fractional calculus are combined to avoid the discontinuous switching phenomenon, so as to suppress the chattering of sliding mode control, and a parameter adaptive law is constructed to approximate the time-varying operating resistance coefficient.

The simulation results show that compared with proportional integral derivative (PID) control and ordinary sliding mode control, the control accuracy of the proposed algorithm in terms of speed is, respectively, improved by 25% and 75%. The error frequency and fluctuation range of the proposed algorithm are reduced in the position error control, the error value tends to 0, and the operation trend tends to be consistent. Therefore, the control method can improve the control accuracy of the system and prove that it has strong immunity.

The algorithm can reduce the influence of external interference in the actual operating environment, realize efficient and stable tracking of trains, and ensure the safety of train control.

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.

Architectural theorists have a long tradition of acknowledging the centrality of building users to architectural production. This article contributes to the discourse on architecture, actor–network theory (ANT), and users by proposing a typology of user translations ranging from supporting to tinkering to adjusting to resisting.

The research utilises an ANT-inspired ethnography of sustainable lighting scripts at the Masdar Institute of Science and Technology (MIST). It comprises semi-structured interviews with MIST designers and students, and site visits and participant observation to understand how the users interpret the scripts and how they interact and change them on a daily basis.

There is a shared understanding that users do not simply receive architectural designs but interpret and change them to suit their preferences. The findings reveal the multiple ways that users interpret and respond to the assumptions of designers and in the process, recast the relations between themselves and their material surroundings.

The research contributes to acknowledging the centrality of users to architectural design processes and the interpretation of design scripts, addressing the limitation in current literature in demonstrating the diversity of ways that users react to such scripts. The research suggests that user actions have significant implications on long-term building performance. It accordingly points to the need for devising multiple means of user involvement in the design process and allowing greater flexibility in design scripts to improve the alignment with user preferences.

The purpose of this paper is to measure Farmer’s adoption tendency towards drought shock, risk-taking networks and modern irrigation technology.

Based on this assumption, this paper evaluated the data gathered from 498 household surveys of Zhangye, Gansu province, PRC, by using the binary probit model. First, the empirical data was analyzed for evaluating the impact of drought shock and risk-taking tendencies on the adoption of modern irrigation technology by farmers. Second, the authors introduced informal risk-bearing networks with formal risks. Final, based on the empirical results, the sustainability test, along with the marginal effect analysis and the degree of impact was carried out.

The results show that the drought shock has a significantly deferent effect on the modern irrigation technology of the farmers. The probability of using technology for each level of drought loss is reduced by 15.02%. The risk-taking network has a significant role in promoting the modern irrigation technology of farmers. The probability of adoption for each additional unit of rural household labor security supply, the likelihood of adoption by farmers increased 23.11%, the probability of approval for each level of relative support, and neighborhood assistance by farmers increased by 13.11% and 17.88% respectively. This study further revealed that insurance purchases enabled farmers to adopt new irrigation technology with the probability increased by 24.99%; easily available bank loans increased the probability of farmers using irrigation technology by 31.89%. From the perspective of interactions between farmers, the risk-taking network can alleviate the inhibitory effect of drought impact towards the adoption of irrigation technology. Among the control variables, the number of years of education, the age of farming, the degree of arable land, the distance from home to the market, and the price of water all has significant effects on the adoption of modern irrigation technology by farmers.

The novelty of the study is that it illustrated the interactive influence of drought shock and risk-taking networks on the farmer’s adoption tendencies of modern irrigation technologies, the inner relationship among drought impact, the risk-taking network and the farmer’s adoption behavior and provide an interactive relationship between the formal risk-taking network and the non-risk-taking network in farmer’s technology adoption.

The purpose of this paper is to analyze how “New Deal” regulatory initiatives, primarily the Securities Acts and the Securities and Exchange Commission (SEC), changed US auditors’ professional knowledge conception, culminating in the 1938 expansion of the Committee on Accounting Procedure (CAP), the first US body to set accounting principles.

The paper combines Halliday’s (1985) knowledge mandates with Hancher and Moran’s (1989) regulatory space to attain a theory-based understanding of auditors’ changing knowledge conceptions amid regulatory pressure. It draws on a range of primary and secondary sources to examine the period from 1929 to 1938.

Following the stock market crash, the newly created SEC aimed to engage auditors as a means to regulate companies’ accounting practices based on a set of codified principles. While entailing increased status, this new role conflicted with the auditors’ knowledge conception, which was based on professional judgment and personal integrity. Pressure from the SEC and academics eventually made auditors agree to a codification of their professional knowledge and create the CAP as a cooperative regulatory solution.

The paper explores the role of auditors’ knowledge conceptions in the emergence of today’s standard setting. It is suggested that auditors’ incomplete control of their professional knowledge made standard setting a form of co-regulation, located between the actors occupying the regulatory space of accounting.

This paper aims to investigate whether revenue diversification affects the financial sustainability of microfinance institutions (MFIs).

The study uses a worldwide panel data set of 443 MFIs in 108 countries for the period 2013–2018 and two-step system Generalized Method of Moments estimation model.

The study finds that revenue diversification has a significant and positive effect on the financial sustainability of MFIs.

The findings of this study actually offer important managerial and policy lessons on MFIs’ financial sustainability. Microfinance managers and policymakers should consider revenue diversification as a strategy through which MFIs can attain financial sustainability instead of overreliance on donations and government subsidies

Unlike previous studies that examined revenue diversification in the context of banking firms, this study contributes to literature by examining the impact of revenue diversification of the financial sustainability of MFIs.

Healthcare systems receive criticism from both providers and recipients. The diversity in these systems throughout the world makes innovation and change difficult. However, a structured analysis of healthcare systems is crucial to identify areas for improvement and to share best practices for the betterment of healthcare throughout the world.

The paper uses organizational theory as an unbiased tool for evaluating healthcare systems. This theory analyses healthcare systems across five dimensions: environment, culture, social structure, physical structure and technology. This analysis provides an in-depth understanding of the organization's surroundings, formation and function. It offers a lens through which healthcare systems can be envisioned and establishes a vocabulary for communication.

Organizational theory presents a multifaceted approach to initiate assessments aiming to enhance existing healthcare systems and customize them to serve all stakeholders within the focused ecosystem. It alters the dynamics of criticism and presents an opportunity to sustainably address unforeseen healthcare challenges in the future. As the author proceeds to understand healthcare organizations through the perspective of organizational theory, the author also uncovers subtle yet crucial issues such as resource dependence, cultural clashes, organizational silence, bureaucracy, hierarchy, ethics, values, engagement and burnout.

This paper was crafted from a collaborative paper for the final of a master's degree. A collaboration was conceptualized using organisation theory as the tool to align processes and achieve successful outcome. The narrative of the collaboration has been edited and paper presented highlighting the importance of the tool of organisation theory in healthcare systems.