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Fully-actuated unmanned aerial vehicles (UAVs) are a growing and promising field of research, which shows advantages for aerial physical interaction. The purpose of this paper is to construct a force sensor-denied control method for a fully-actuated hexarotor to conduct aerial interaction with accurate force exerted outward.

First, by extending single-dimension impedance model to the fully-actuated UAV model, an impedance controller is designed for compliant UAV pose/force control. Then, to estimate the interaction force between UAV end-effector and external environment accurately, combined with super-twisting theory, a nonlinear force observer is constructed. Finally, based on impedance controller and estimated force from observer, an interaction force regulation method is proposed.

The presented nonlinear observer-based impedance control approach is validated in both simulation and environments, in which the authors try to use a fully-actuated hexarotor to accomplish the task of aerial physical interaction finding that a specified force is able to be exerted to environment without any information from force sensors.

A solution of aerial physical interaction for UAV system enabling accurate force exerted outward without any force sensors is proposed in this paper.

This study aims to propose a methodology aimed at understanding the cognitive and physiological processes inherent in cadet pilot operations. Through analyzing responses from two cadet pilots with varied experience levels across diverse simulation scenarios, the research uses descriptive statistics, t-test, one-way ANOVA and percentage change analysis to explore crucial variables, including heart rate (HR), heart rate variability (HRV) and respiratory rate (RR).

The investigation meticulously examines HR, HRV and RR under circumstances encompassing resting state, visual flight rules and instrument flight rules with engine failure. Pilots undergo comprehensive analyses employing statistical techniques and visual representations to comprehend cognitive loads and physiological adaptations.

Significant disparities emerge between the two pilots, elucidating the profound impact of experience on cognitive and physiological outcomes. Novice cadet pilots exhibit heightened variability during scenario transitions, while experienced cadet pilot demonstrate controlled responses, indicative of adaptability. Visual flight simulations evoke distinct responses, whereas instrument-based scenarios, particularly those simulating emergencies, lead to pronounced physiological changes.

The findings of this research hold practical significance in introducing the proposed novel methodology for monitoring Cadet pilots to refine pilot training simulation protocols and enhance aviation safety by illuminating the interplay between experience levels and scenario complexities.

This study proposes a novel methodology for investigating cognitive and physiological responses in pilot operations, mainly investigating cadet pilots’ vital parameters through diverse analytical methods and an exploration of scenario-specific demands.

The study aims to equip robots with the ability to precisely maintain interaction forces, which is crucial for tasks such as polishing in highly dynamic environments with unknown and varying stiffness and geometry, including those found in airplane wings or thin, soft materials. The purpose of this study is to develop a novel adaptive force-tracking admittance control scheme aimed at achieving a faster response rate with higher tracking accuracy for robot force control.

In the proposed method, the traditional admittance model is improved by introducing a pre-proportional-derivative controller to accelerate parameter convergence. Subsequently, the authors design an adaptive law based on fuzzy logic systems (FLS) to compensate for uncertainties in the unknown environment. Stability conditions are established for the proposed method through Lyapunov analysis, which ensures the force tracking accuracy and the stability of the coupled system consisting of the robot and the interaction environment. Furthermore, the effectiveness and robustness of the proposed control algorithm are demonstrated by simulation and experiment.

A variety of unstructured simulations and experimental scenarios are designed to validate the effectiveness of the proposed algorithm in force control. The outcomes demonstrate that this control strategy excels in providing fast response, precise tracking accuracy and robust performance.

In real-world applications spanning industrial, service and medical fields where accurate force control by robots is essential, the proposed method stands out as both practical and straightforward, delivering consistently satisfactory performance across various scenarios.

This research introduces a novel adaptive force-tracking admittance controller based on FLS and validated through both simulations and experiments. The proposed controller demonstrates exceptional performance in force control within environments characterized by unknown and varying.

The building sector contributes one-third of the energy-related carbon dioxide globally. Therefore, framing appropriate energy-related policies for the next decades becomes essential in this scenario to realize the global net-zero goals. The purpose of the proposed study is to evaluate the impact of the widespread adoption of such guidelines in a building community in the context of mixed-mode buildings.

This study decentralizes the theme of improving the energy efficiency of the national building stock in parcels by proposing a community-based hybrid bottom-up modelling approach using urban building energy modelling (UBEM) techniques to analyze the effectiveness of the community-wide implementation of energy conservation guidelines.

In this study, the UBEM is developed and validated for the 14-building residential community in Mumbai, India, adopting the framework. Employing Energy Conservation Building Code (ECBC) compliance on the UBEM shows an energy use reduction potential of up to 15%. The results also reveal that ECBC compliance is more advantageous considering the effects of climate change.

In developing countries where the availability of existing building stock information is minimal, the proposed study formulates a holistic framework for developing a detailed UBEM for the residential building stock from scratch. A unique method of assessing the actual cooling load of the developed UBEM is presented. A thorough sensitivity analysis approach to investigate the effect of cooling space fraction on the energy consumption of the building stock is presented, which would assist in choosing the appropriate retrofit strategies. The proposed study's outcomes can significantly transform the formulation and validation of appropriate energy policies.

This paper aims to evaluate the accessibility of digital information systems as a key usability attribute in information retrieval by users with visual impairment (VI), to inform development of accessible information systems.

This study used a cross-sectional survey design based on the quantitative research paradigm. Data was collected from 117 students with visual impairments from selected public universities in Kenya, using a semi-structured questionnaire adapted from Web Content Accessibility Guidelines.

This study revealed that gender did not influence screen reader compatibility, alternative format preferences, perceptions of accessible content or digital library navigability. Instead, type of visual impairment, prior assistive technology (AT) training and digital library use frequency significantly impacted these attributes. Blind students reported positive experiences, favouring alternative formats, and expressed positive views on accessible content while those with low vision faced more challenges. Prior training in assistive technology and frequent digital library use resulted in higher screen reader compatibility and better navigability. Increased digital library use was linked to access to alternative content for those with prior assistive technology training.

This study contributes to the existing literature on accessibility of digital information systems for users with visual impairments. Further research is needed to explore other factors that may influence the accessibility of digital systems, such as the design of user interfaces as well as an evaluation of accessibility of digital systems for other categories of disabilities such as hearing impairment, physical impairment, autism and intellectual disability, among others.

The findings of this study have practical implications for the design and development of digital systems such as digital libraries. Developers can leverage findings of this study to enhance compatibility of digital platforms with screen readers and provide alternative formats and accessible content. User-centred design principles can be used to create interfaces that are easy to navigate and friendly to users with visual impairments. Training programmes on assistive technology should be provided to users to enhance their skills and confidence in using digital systems.

This study contributes towards design and creation of navigable systems that are compatible with screen readers. The study also points out the importance of creating more inclusive and usable digital environments for persons with visual impairments.

This study aims to introduce a predictive homogenization model incorporating electrical percolation considerations to forecast the electrical characteristics of unidirectional carbon-epoxy laminate composites.

This study presents a method for calculating the electrical conductivity tensor for various ply arrangement patterns to elucidate phenomena occurring around the interfaces between plies. These interface models are then integrated into a three-dimensional (3D) magneto-thermal model using the finite element method. A comparative study is conducted between different approaches, emphasizing the advantages of the new model through experimental measurements.

This research facilitates the innovative integration of electrical percolation considerations, resulting in substantial improvement in the prediction of electrical properties of composites. The validity of this improvement is established through comprehensive validation against existing approaches and experimentation.

The study primarily focuses on unidirectional carbon-epoxy laminate composites. Further research is needed to extend the model's applicability to other composite materials and configurations.

The proposed model offers a significant improvement in predicting the electrical properties of composite materials by incorporating electrical percolation considerations at inter-ply interfaces, which have not been addressed in previous studies. This research provides valuable information to improve the accuracy of predictions of the electrical properties of composites and offers a methodology for accounting for these properties in 3D magneto-thermal simulations.

The performance of a bladeless Tesla turbine is closely tied to momentum diffusion, kinetic energy transfer and wall shear stress generation on its rotating disks. The surface roughness adds complexity of flow analysis in such a domain. This paper aims to assess the effect of roughness on flow structures and the application of roughness models in flow cross sections with submillimeter height, including both stationary and rotating walls.

This research starts with the examination of flow over a rough flat plate, and then proceeds to study flow within minichannels, evaluating the effect of roughness on flow characteristics. An in-house test stand validates the numerical solutions of minichannel. Finally, flow through the minichannel with corotating walls was analyzed. The k-ω SST turbulent model and Aupoix's roughness method are used for numerical simulations.

The findings emphasize the necessity of considering the constricted dimensions of the flow cross section, thereby improving the alignment of derived results with theoretical estimations. Moreover, this study explores the effects of roughness on flow characteristics within the minichannel with stationary and rotating walls, offering valuable insights into this intricate phenomenon, and depicts the appropriate performance of chosen roughness model in studied cases.

The originality of this investigation is the assessment and validation of flow characteristics inside minichannel with stationary and corotating walls when the roughness is implemented. This phenomenon, along with the effect of roughness on the transportation of kinetic energy to the rough surface of a minichannel in an in-house test setup, is assessed.

There are several studies showing that end-users' participation in the architectural design process of houses is critical to their satisfaction (e.g. Önder et al., 2010; Ammar et al., 2013). Housing that is not adjusted to inhabitants' needs leads to modification works (Davidson et al., 2007) that could be avoided if their design was defined from the beginning with their participation. Digital technologies, such as 3D interactive visualization, benefit co-design processes by helping non-specialists better understand space and design possibilities (Salter et al., 2009; Schroth et al., 2006). However, the available literature shows that existing co-design digital tools were not developed based on potential users’ requirements. This paper aims to define the user requirements of a co-design tool for housing customization.

Interviews were conducted to gather information on how participatory processes occur in housing cooperatives and identify how potential users can collaborate in the design definition of their houses using a digital tool.

The interviews were analyzed, and requirements were defined.

This work contributes to the advancement of knowledge since the tool is defined based on requirements collected from potential end-users. By using a user-centered approach, the tool can contribute to more effective and informed collaboration.

The paper’s main goal is to examine the relationship between the video marketing of financial technologies (Fintechs) and their vulnerable website customers’ brand engagement in the ongoing coronavirus disease 2019 (COVID-19) crisis.

To extract the required outcomes, the authors gathered data from the five biggest Fintech websites and YouTube channels, performed multiple linear regression models and developed a hybrid (agent-based and dynamic) model to assess the performance connection between their video marketing analytics and vulnerable website customers’ brand engagement.

It has been found that video marketing analytics of Fintechs’ YouTube channels are a decisive factor in impacting their vulnerable website customers’ brand engagement and awareness.

By enhancing video marketing analytics of their YouTube channels, Fintechs can achieve greater levels of vulnerable website customers’ engagement and awareness. Higher levels of vulnerable customers’ brand engagement and awareness tend to decrease their vulnerability by enhancing their financial knowledge and confidence.

Fintechs should aim to increase the number of total videos on their YouTube channels and provide videos that promote their customers’ knowledge of their services to increase their brand engagement and awareness, thus reducing their vulnerability. Moreover, Fintechs should be aware not to over-post videos because they will be in an unfavorable position against their competitors.

This research offers valuable insights regarding the importance of video marketing strategies for Fintechs in promoting their vulnerable website customers’ brand awareness during crisis periods.

The purpose of this study is to explore the knowledge, attitude and practices (KAP) of Industry 4.0 between the academicians and industry players in construction engineering, further suggesting a mechanism to narrow the gap between the distinct parties.

This study was conducted through structured online and face-to-face interviews, using KAP survey, and semi-structured interviews. This constructive research was conducted among Malaysian construction industry players and academicians from the construction engineering department in public universities.

The findings exhibit the similarities and differences of KAP between academics and industry on Industry 4.0 in construction engineering. In general, both categories of respondents have displayed more similarities than differences in all aspects, except for knowledge. The better knowledge profile of Industry 4.0 among the academicians reflects the nature of the academic works that constantly seek new knowledge, thus suggesting the establishment of an industry-academic (I-A) knowledge equilibrium framework to leverage the knowledge profile between both parties.

This exploratory study that showcases the perspective of the academia and industry practitioners on Industry 4.0 acts as a cornerstone for bridging the gap between the two distinct sectors within the same field.

The gap between the academic and industry was highlighted, further establishing the I-A knowledge equilibrium framework that could also be applied to other fields of study.

The originality of this paper was the profiling of the KAP of Industry 4.0 for the academicians and industry players in construction engineering, further distinguishing the gap between both parties.