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Asteroids have the characteristics of noncooperative, irregular gravity and complex terrain on the surface, which cause difficulties in successful landing for conventional landers. The purpose of this paper is to study the trajectory tracking problem of a multi-node flexible lander with unknown flexible coefficient and space disturbance.

To facilitate the stability analysis, this paper constructs a simplified dynamic model of the multi-node flexible lander. By introducing the nonlinear transformation, a concurrent learning-based adaptive trajectory tracking guidance law is designed to ensure tracking performance, which uses both real-time information and historical data to estimate the parameters without persistent excitation (PE) conditions. A data selection algorithm is developed to enhance the richness of historical data, which can improve the convergence rate of the parameter estimation and the guidance performance.

Finally, Lyapunov stability theory is used to prove that the unknown parameters can converge to their actual value and, meanwhile, the closed-loop system is stable. The effectiveness of the proposed algorithm is further verified through simulations.

This paper provides a new design idea for future asteroid landers, and a trajectory tracking controller based on concurrent learning and preset performance is first proposed.

Additive lamination manufacturing (ALM), as a novel additive manufacturing technology, builds up the geometry via the lamination of fiber-reinforced polymer (FRP) fabric laterally, rendering it suitable for fabricating large-scale Stay-in-Place concrete formwork. This paper aims to investigate the control parameters and structure performance of ALM and assess its application for the fabrication of large-scale concrete formwork.

Based on previous feasibility studies, this research systematically investigates the control and material parameters that influence horizontal and vertical extrusion speeds, as well as the overall quality of ALM. Once the system parameters are established, a series of prototypes are fabricated and tested to validate the tensile strength of the formwork and its reinforcement capabilities. In addition, this study assesses the potential geometric freedom and implementation constraints of ALM.

This research identifies the essential control parameters for path planning in ALM and examines their impact on fabrication. In addition, this paper evaluates ALM’s strengths and limitations in producing concrete formwork for large-scale concrete structures, comparing these to industry benchmarks.

A critical challenge in additive manufacturing lies in its scalability and compatibility with existing construction processes. In comparison to concrete, FRP offers advantages such as being lighter, easier to handle and providing surface protection and reinforcement. These qualities make FRP superior for formwork and compatible with existing building standards. Despite its advantages and potential, the current path planning and control model in 3D printing do not apply to ALM due to its novel build-up process. Also, the performance of fabricated parts as part of integrated large-scale structures is yet to be studied.

This study aims to improve the control accuracy and antidisturbance performance of the manipulator with the flexible link, a combined controller, which combines the novel backstepping sliding mode controller based on the extended state observer (ESO) and super-twisting sliding mode controller.

First, the dynamic of the system is constructed by Lagrange method and assumed mode method, and then the dynamic is decoupled by the singular perturbation theory to obtain the slow-varying subsystem and fast-varying subsystem. For the slow-varying subsystem, the novel backstepping sliding mode controller based on ESO is used to achieve joint tracking. For the fast-varying subsystem, the super-twisting sliding mode controller is used for vibration suppression. At the same time, to suppress chattering, the tanh function is used to replace the sign function in the reaching law.

The simulation results show that the combined control has better trajectory tracking performance, antiinterference performance and vibration suppression performance than traditional sliding mode control (SMC).

A novel backstepping sliding mode controller based on ESO is designed to guarantee the performance of the tracking trajectory. The new controller improves the converge rate. A super-twisting sliding mode controller, which can stabilize the fast-varying subsystem, is used to suppress the vibration of flexible link.

The pharmaceutical industry is facing significant pressure to tackle antimicrobial resistance (AMR). Other ecological, societal and regulatory pressures are also driving the industry to “go green”. While such a (green) transition could be possible through appropriate green practices’ implementation, the present understanding about it is superficial and vague. A key reason is the lack of green practices’-related studies on pharmaceuticals, which are also insufficiently comprehensive. This knowledge gap is sought to be addressed.

A systematic literature review (SLR) was conducted with 73 carefully selected articles, then subjected to thematic content analyses for synthesising the relevant themes and sub-themes.

Around 76 operational-level green practices covering all key stakeholders across the drug lifecycle were identified. It was revealed that designing drugs having accelerated environmental degradability is important to combat AMR. Also, redesigning existing drugs is environmentally more resource-intensive than developing new ones with significant cost-saving potential in solvent recycling and flexible manufacturing, both of which are not common at present. With regards to green-related barriers, stringent quality requirements on drugs (and therefore risks in making relevant green-oriented modifications) and time-consuming and costly regulatory approvals were found to be the key ones.

The operational green practices’ framework developed for individual pharmaceutical supply chain stakeholders could help practitioners in benchmarking, modifying and ultimately, adopting green practices. The findings could also assist policymakers in reframing existing regulations, such as Good Manufacturing Practices or GMP-related, to promote greener drug development.

This work is the first systematic attempt to identify and categorise operational-level green supply chain practices across stakeholders in the pharmaceutical sector.

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  Biodegradability of drugs is more important than environmental degradability.

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  Flexible manufacturing process design (or quality by design) reduces resource wastage.

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  Ecopharmacovigilance is effective in combating PIE and AMR-related issues.

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  Upstream and downstream coordination is key to greening pharma operations.

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  Costly and time-consuming regulatory approval is a key barrier to greening pharma processes.

Biodegradability of drugs is more important than environmental degradability.

Flexible manufacturing process design (or quality by design) reduces resource wastage.

Ecopharmacovigilance is effective in combating PIE and AMR-related issues.

Upstream and downstream coordination is key to greening pharma operations.

Costly and time-consuming regulatory approval is a key barrier to greening pharma processes.

This study examined the implementation of an agile-blended learning (ABL) approach in a master-level early childhood research course and assessed its impact on the learning experience. The purpose was to understand how incorporating ABL concepts affected flexibility, learner autonomy, collaboration and technology mediation, the core principles of ABL.

A participatory case study methodology was employed to gather insights from 40 students regarding their experiences in the redesigned research course. Data were collected through interviews, observations and document analysis. Qualitative data were thematically analyzed and quantitative data descriptively analyzed.

ABL fostered flexibility, convenience and learner autonomy. However, students desired richer interpersonal interactions. Technological integration enhanced learning, but social presence was lacking.

The study was limited to a specific master-level early childhood education course and focused on a particular group of students. Further research is needed to examine the generalizability of the findings in different educational contexts and student populations.

Recommendations include ongoing professional development and support systems to optimize ABL realization. Sustaining ABL practices necessitates flexible, empowering institutional structures.

This study contributes to the literature by exploring the potential of ABL in the context of early childhood research education. It provides empirical evidence of the benefits of ABL for increased flexibility, learner autonomy, collaboration and technology mediation. The case study design adds to the originality by offering insights into the practical implementation of ABL in an educational setting.

User diversity has been discussed in many fields of study for decades. Nevertheless, some cohorts are rarely included in mainstream research. According to the concept of universal design of research (UDR), people with disabilities should be more often included in participant pools. There is, however, a need for certain methodological considerations to achieve UDR.

The suggested guidelines are based upon existing guidelines and research in addition to key takeaways from studies conducted by the authors over the past 15 years. Six studies are used to show how the guidelines can be applied in research involving three example cohorts, namely people with dyslexia, aphasia and intellectual disability.

Extensive guidelines are needed to increase user inclusion in mainstream studies and support researchers in conducting purposeful and ethical research. The suggested guidelines should be examined for other cohorts to ensure that all types of user needs are accommodated.

This study contributes with methodological approaches to enhance inclusion of all types of participants in mainstream research.

The main contribution is The seven principles of UDR, a further development of the original principles for UDR.

The purpose of this paper is to actively calibrate power density to match the application requirements with as small an actuator as possible. So, this paper introduces shape memory alloy to design variable stiffness elements. Meanwhile, the purpose of this paper is also to solve the problem of not being able to install sensors on shape memory alloy due to volume limitations.

This paper introduces the design, modeling and control process for a variable stiffness passive ankle exoskeleton, adjusting joint stiffness using shape memory alloy (SMA). This innovative exoskeleton aids the human ankle by adapting the precompression of elastic components by SMA, thereby adjusting the ankle exoskeleton’s integral stiffness. At the same time, this paper constructs a mathematical model of SMA to achieve a dynamic stiffness adjustment function.

Using SMA as the driving force for stiffness modification in passive exoskeletons introduces several distinct advantages, inclusive of high energy density, programmability, rapid response time and simplified structural design. In the course of experimental validation, this ankle exoskeleton, endowed with variable stiffness, proficiently executed actions like squatting and walking and it can effectively increase the joint stiffness by 0.2 Nm/Deg.

The contribution of this paper is to introduce SMA to adjust the stiffness to actively calibrate power density to match the application requirements. At the same time, this paper constructs a mathematical model of SMA to achieve a dynamic stiffness adjustment function.

The purpose of this paper is to propose and validate a theoretical model to investigate the relationship between self-organisation, information integration, adaptability and supply chain agility in humanitarian organisations.

A theoretical model was developed from extant studies and assessed through a structured questionnaire survey of 86 humanitarian organisations operating in South Sudan. The data were analysed using partial least square structural equation modelling.

The study found that self-organisation has a discernible positive influence on supply chain agility not only directly but also indirectly through adaptability. Further, information integration does not significantly influence supply chain agility directly but is fully mediated by adaptability. Together, the antecedent variables account for 53.9% variance in supply chain agility.

This study contributes to providing an empirical understanding of a humanitarian supply chain as a complex adaptive system and hence the need to incorporate self-organising and adaptive dimensions in supply chain management practice. Furthermore, it confirms the centrality of the complex adaptive system feature of adaptability when building supply chain agility through self-organisation and information integration.

The findings provide a firm ground for managerial decisions on investment in self-organisation and information integration dimensions so as to enhance adaptability and improve supply chain agility in humanitarian organisations.

This study is distinctive in the sense that it uses the complex adaptive system variables to empirically validate the relationships between self-organisation, information integration, adaptability and supply chain agility in humanitarian organisations in the world’s youngest developing economy with a long history of conflict and humanitarian intervention. The mediating influence of adaptability examined in this study is also novel.

In today’s rapidly evolving work landscape, the design of office spaces is a crucial concern for organizations. Companies are redefining offices as collaboration hubs to entice employees back to in-person work. However, the understanding of how employees choose their workspaces, especially for collaborative activities, and how this should inform office design is lacking. Workers’ collaborative activity patterns can help better understand workspace choice behavior (WCB). In two studies, this paper aims to explore which characteristics of collaborative activities to consider when reshaping offices.

Data collected in a cross-sectional study design at a research institution (n = 285) and a university (n = 352) were used for confirmatory factor analyses and regression analysis.

The first study shows that collaborative activities can be classified into three distinct types: coordinative activities (planned and formal), deep collaboration (planned and complex) and spontaneous communication (informal and short encounters). The second study revalidates this classification and reveals patterns impacting WCB. Frequency and location preference of spontaneous communication and work environment satisfaction are strong predictors of on-site work. Personal characteristics like gender, age, managerial position or commute time are less consequential than assumed.

The results pinpoint guidelines for office designers and leaders in shaping effective workspaces and policies.

This paper provides new insights into classifying collaborative activities and personal characteristics, activity characteristics and environmental factors influencing WCB.

This study aims to develop a methodology that extracts an architectural concept from a biological analogy that integrates forms and kinetic behavior to identify whether complex forms work better or simple forms with proper kinetic behavior for improving visual comfort and daylight performance.

The research employs a transdisciplinary approach using several methods consisting of a biomimetic functional-morphological approach, kinetic design strategy, case study comparison using algorithmic workflow and parametric simulation and inverse design, to develop an interactive kinetic façade with optimized daylight performance.

A key development is the introduction of a periodic interactive region (PIR), which draws inspiration from the butterfly wings' nanostructure. These findings challenge conventional perspectives on façade complexity, highlighting the efficacy of simpler shapes paired with appropriate kinetic behavior for improving visual comfort. The results show the façade with a simpler “Bookshelf” shape integrated with a tapered shape of the periodic interactive region, outperforms its more complex counterpart (Hyperbolic Paraboloid component) in terms of daylight performance and glare control, especially in southern orientations, ensuring occupant visual comfort by keeping cases in the imperceptible range while also delivering sufficient average spatial Daylight Autonomy of 89.07%, Useful Daylight Illuminance of 94.53% and Exceeded Useful Daylight Illuminance of 5.11%.

The investigation of kinetic façade studies reveals that precedent literature mostly focused on engineering and building physics aspects, leaving the architectural aspect underutilized during the development phase. Recent studies applied a biomimetic approach for involving the architectural elements besides the other aspects. While the biomimetic method has proven effective in meeting occupants' visual comfort needs, its emphasis has been primarily on the complex form which is difficult to apply within the kinetic façade development. This study can address two gaps: (1) the lack of an architectural aspect in the kinetic façade design specifically in the development of conceptual form and kinetic behavior dimensions and (2) exchanging the superficial biomimetic considerations with an in-depth investigation.