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The purpose of this review is to comprehensively consider the material properties and processing of additive titanium alloy and provide a new perspective for the robotic grinding and polishing of additive titanium alloy blades to ensure the surface integrity and machining accuracy of the blades.

At present, robot grinding and polishing are mainstream processing methods in blade automatic processing. This review systematically summarizes the processing characteristics and processing methods of additive manufacturing (AM) titanium alloy blades. On the one hand, the unique manufacturing process and thermal effect of AM have created the unique processing characteristics of additive titanium alloy blades. On the other hand, the robot grinding and polishing process needs to incorporate the material removal model into the traditional processing flow according to the processing characteristics of the additive titanium alloy.

Robot belt grinding can solve the processing problem of additive titanium alloy blades. The complex surface of the blade generates a robot grinding trajectory through trajectory planning. The trajectory planning of the robot profoundly affects the machining accuracy and surface quality of the blade. Subsequent research is needed to solve the problems of high machining accuracy of blade profiles, complex surface material removal models and uneven distribution of blade machining allowance. In the process parameters of the robot, the grinding parameters, trajectory planning and error compensation affect the surface quality of the blade through the material removal method, grinding force and grinding temperature. The machining accuracy of the blade surface is affected by robot vibration and stiffness.

This review systematically summarizes the processing characteristics and processing methods of aviation titanium alloy blades manufactured by AM. Combined with the material properties of additive titanium alloy, it provides a new idea for robot grinding and polishing of aviation titanium alloy blades manufactured by AM.

The purpose of this paper is to analyze if the sport trajectory could be an impact factor in leadership development.

A qualitative research method has been adopted by conducting 17 in-depth, semi-structured interviews. The data were analyzed with the program Open Code (4.03).

The findings of this study revealed that the interviewed managers perceived that their sport trajectory has had an important influence in the development of their leadership. This influence is determined by four factors: (1) sport profile, (2) sport referents, (3) competences, values and abilities and (4) experiences from different sport roles played during their lifespan.

The research is based on interviews with a small sample of managers. In order to develop the research further, a more extensive sample is required.

The paper is unique as it examines the impact of the sport trajectory as an impact factor in leadership development.

This paper aims to present numerical simulations for a series of flight processes for the postlaunching stage of the “balloon-borne UAV system.” It includes the balloon further ascent motion after airborne launching. In terms of unmanned aerial vehicles (UAVs), the tailspin state and the charge-out process with an anti-tailspin parachute-assisted suspending are analyzed. Then, the authors conduct trajectory optimization simulations for the long-distance gliding process.

The balloon kinematics model and the parachute Kane multibody dynamic model are established. Using steady-state tailspin to reduced-order analysis and achieving change-out simulation by parachute suspension dynamic model. A reentry optimization control problem is developed and the Radau pseudo-spectral method is used to calculate the glide trajectory.

The established dynamic model and trajectory optimization method can effectively simulate the motion process of balloons and UAVs. The system mass reduction for launching UAVs will not cause damage to the balloon structure. The anti-tailspin parachute can reduce the UAV attack angles effectively. The UAV can glide to the designated target position by adjusting the attack angle and sideslip angle. The farthest flight distance after launching from 20 km height is 94 km and the gliding time is 40 min, which demonstrates the potential application advantage of high-altitude launching.

The research content and related conclusions of this article achieve a closed-loop analysis of the flight mission chain for the “balloon-borne UAV system,” which provides simulation references for relevant balloon launching experiments.

This paper establishes a complete set of numerical simulation models and can effectively analyze various postlaunching behaviors.

The purpose of this paper is to propose a new velocity prediction navigation algorithm to develop a conflict-free path for robots in dynamic crowded environments. The algorithm BP-prediction and reciprocal velocity obstacle (PRVO) combines the BP neural network for velocity PRVO to accomplish dynamic collision avoidance.

This presented method exhibits innovation by anticipating ahead velocities using BP neural networks to reconstruct the velocity obstacle region; determining the optimized velocity corresponding to the robot’s scalable radius range from the error generated by the non-holonomic robot tracking the desired trajectory; and considering acceleration constraints, determining the set of multi-step reachable velocities of non-holonomic robot in the space of velocity variations.

The method is validated using three commonly used metrics of collision rate, travel time and average distance in a comparison between simulation experiments including multiple differential drive robots and physical experiments using the Turtkebot3 robot. The experimental results show that our method outperforms other RVO extension methods on the three metrics.

In this paper, the authors propose navigation algorithms capable of adaptively selecting the optimal speed for a multi-robot system to avoid robot collisions during dynamic crowded interactions.

This paper delves into cross-border E-business, unraveling its intricate dynamics and forecasting its future trajectory.

This paper projects the prospective market size of cross-border E-business in China for the year 2023 using the GM (1,1) gray forecasting model. Furthermore, to enhance the analysis, the paper attempts to simulate and forecast the size of China’s cross-border E-business sector using the GM (1,3) gray model. This extended model considers not only the historical trends of cross-border E-business but also the growth patterns of GDP and the digital economy.

The forecast indicates a market size of 18,760 to 18,934 billion RMB in 2023, aligning with the consistent growth observed in previous years. This suggests a sustained positive trajectory for cross-border E-business.

Cross-border e-commerce critically shapes China’s global integration and traditional industry development. The research in this paper provides insights beyond statistical trends, contributing to a nuanced understanding of the pivotal role played by cross-border e-commerce in shaping China’s economic future.

Research highlights that residential care experienced children and young people in Scotland have poorer educational outcomes than their peers within the wider population. Despite this, poor educational attainment is not inevitable, and further research is needed to increase the understanding of long-term trajectories. This paper aims to address a gap in contemporary literature that is of benefit to practitioners, academics and policymakers. Despite experiencing adversity, attachment, separation and loss, school attainment data on leaving care only reflects part of the educational journey.

Using a mixed methodology and social constructionist theoretical framework, a practitioner-led PhD study gathered data from questionnaires and qualitative information from 13 semi-structured interviews with young people who had experienced residential care in Scotland. Recruitment was through a gatekeeper within a national third-sector organisation. The educational trajectories for young people with experience of residential care in Scotland are complex. A lived experience perspective from a PhD study illustrates that statistical data only captures part of the journey and the author needs to reconsider how success is measured.

Of the 13 participants in the study, 12 achieved success educationally, although for the majority of those interviewed, attainment continued after leaving compulsory education. Barriers to greater success included placement uncertainty and movement, stigma, low expectations, pressure to not become a statistic, procedural obstacles and inconsistency or poor relationships.

Supportive relationships and stable placements can create circumstances conducive to effective learning, but evidence reflects that support is necessary throughout the life course if children, young people and adults with care experience are to reach their full academic potential.

Research into the educational outcomes for those with experience of residential care in Scotland is limited. This paper, from a PhD, provides lived experience accounts from a practitioner-led study.

This paper focuses on the application of a robotic technique for modeling a three-wheeled mobile robot (WMR), considering it as a multibody polyarticulated system. Then the dynamic behavior of the developed model is verified using a physical model obtained by Simscape Multibody.

Firstly, a geometric model is developed using the modified Denavit–Hartenberg method. Then the dynamic model is derived using the algorithm of Newton–Euler. The developed model is performed for a three-wheeled differentially driven robot, which incorporates the slippage of wheels by including the Kiencke tire model to take into account the interaction of wheels with the ground. For the physical model, the mobile robot is designed using Solidworks. Then it is exported to Matlab using Simscape Multibody. The control of the WMR for both models is realized using Matlab/Simulink and aims to ensure efficient tracking of the desired trajectory.

Simulation results show a good similarity between the two models and verify both longitudinal and lateral behaviors of the WMR. This demonstrates the effectiveness of the developed model using the robotic approach and proves that it is sufficiently precise for the design of control schemes.

The motivation to adopt this robotic approach compared to conventional methods is the fact that it makes it possible to obtain models with a reduced number of operations. Furthermore, it allows the facility of implementation by numerical or symbolical programming. This work serves as a reference link for extending this methodology to other types of mobile robots.

This research study aims to minimize autonomous flight cost and maximize autonomous flight performance of a slung load carrying rotary wing mini unmanned aerial vehicle (i.e. UAV) by stochastically optimizing autonomous flight control system (AFCS) parameters. For minimizing autonomous flight cost and maximizing autonomous flight performance, a stochastic design approach is benefitted over certain parameters (i.e. gains of longitudinal PID controller of a hierarchical autopilot system) meanwhile lower and upper constraints exist on these design parameters.

A rotary wing mini UAV is produced in drone Laboratory of Iskenderun Technical University. This rotary wing UAV has three blades main rotor, fuselage, landing gear and tail rotor. It is also able to carry slung loads. AFCS variables (i.e. gains of longitudinal PID controller of hierarchical autopilot system) are stochastically optimized to minimize autonomous flight cost capturing rise time, settling time and overshoot during longitudinal flight and to maximize autonomous flight performance. Found outcomes are applied during composing rotary wing mini UAV autonomous flight simulations.

By using stochastic optimization of AFCS for rotary wing mini UAVs carrying slung loads over previously mentioned gains longitudinal PID controller when there are lower and upper constraints on these variables, a high autonomous performance having rotary wing mini UAV is obtained.

Approval of Directorate General of Civil Aviation in Republic of Türkiye is essential for real-time rotary wing mini UAV autonomous flights.

Stochastic optimization of AFCS for rotary wing mini UAVs carrying slung loads is properly valuable for recovering autonomous flight performance cost of any rotary wing mini UAV.

Establishing a novel procedure for improving autonomous flight performance cost of a rotary wing mini UAV carrying slung loads and introducing a new process performing stochastic optimization of AFCS for rotary wing mini UAVs carrying slung loads meanwhile there exists upper and lower bounds on design variables.

This study aims to address the noted gap in comprehensive overviews detailing the developmental trajectory of Islamic finance (IF) as an interdisciplinary academic field.

The study introduces a unique approach using the combined methodologies of co-word analysis and main path analysis (MPA) by examining a broad collection of IF research articles.

The investigation identifies dominant themes and foundational works that have influenced the IF discipline. The data reveals prominent areas such as Shariah governance, financial resilience, ethical dimensions and customer-centric frameworks. The MPA offers detailed insights, narrating a journey from the foundational principles of IF to its current challenges and opportunities. This journey covers harmonizing religious beliefs with contemporary financial models, changes in regulatory landscapes and the continuous effort to align with broader socioeconomic aspirations. Emerging areas of interest include using new technologies in IF, standardizing global Islamic banking and assessing its socioeconomic effects on broader populations.

This study represents a pioneering effort to map out and deepen the understanding of the IF field, highlighting its dynamic evolution and suggesting potential avenues for future academic exploration.

Lead is a well-established environmental contaminant that over the last 50 years has become recognized as a neurotoxin with its greatest concern for the developing child (i.e. both in-utero and postnatally). What is problematic is that children exposed to lead often come from lower socioeconomic status (SES), are largely Black communities and are further at increased risk for developing adverse childhood experiences (ACEs). The literature on ACEs had focused much on trauma, single parenting, child abuse, lack of finances and stress, etc., but has not considered the intersectionality of these ACEs as risk factors within environmental neurotoxic exposures such as lead poisoning. This is important as most low SES communities are Black. In particular, within the New York City Housing Authority (NYCHA), Black families have been neglected of proper lead-abatement to their apartments for nearly 70 years.

This is a viewpoint/perspective paper that examines the lived experiences of Black folxs in NYCHA through a Black critical theory (BlackCrit) and antiblackness framework pertaining to ACEs, and lead poisoning within the NYCHA system of New York City. This perspective paper draws upon the last three years of news reports, five decades of publicly available data sets from NYCHA and the comptroller to raise an awareness of how Black children are treated by NYCHA generation after generation which can be argued as a mass atrocity against NYCHA residents. Furthermore, the systematic and institutionalized racism and environmental injustices by NYCHA and the state can also be considered as a crime against humanity. As such, BlackCrit could help to position awareness, advocacy and knowledge about Black folxs residing in NYCHA to achieve fair, safe and affordable public housing to experience Black joy across future generations.

Thus, rather than civic and state government response efforts focusing their full attention and resources to serving and supporting individuals affected by ACEs they should equally consider the environments in which Black people live and also allocate funds proportionally to address these areas often overlooked. Moreover, proportions of these funds should be redirected especially to lead-abatement and removal of known sources of lead exposures, evaluation of suspected sources of lead exposures (i.e. drinking water, baby food and formula, children’s juice and cereal products, superfund and other waste sites, electronic recycling plants, etc.) and accompanied by all affected children undergoing full and comprehensive neuropsychological testing and follow up studies paid for by the state. The goal should have two fundamental objectives: (1) accepting accountability for failing to address these preventable neuropsychological issues directly affecting Black children generation after generation and (2) offering the proper waived or reimbursable supports and resources to help Black children sustain the best quality of life (QOL) trajectory possible when diagnosed with lead poisoning.

The manuscript is a viewpoint/perspective paper grounded in BlackCrit and an antiblackness framework. There are ample public news reports and public data available from NYCHA on these matters over the last three years. However, the scope of this paper was not to delve too deep into these numbers per se, but rather to address the concerns leading up to and arguably contributing to, at least in part, to these numbers of lead-exposed Black children in NYCHA. Lead poisoning has never been considered as an ACE and its relationship to mass atrocity research is novel which may pave a new avenue for research of this kind through the utility of BlackCrit and antiblackness framework to support and advocate for change so that Black children can be provided with a basic human right of safe housing and experience Black joy.

BlackCrit has not been used in the context of lead poisoning research. Mostly individuals and families of middle- and low-income have been studied in the context of poverty and lead poisoning. However, many people who live in poverty, in public housing, within New York are Black. Thus, Black children are generation after generation exposed to unaddressed lead-abatement and it appears that now more than ever BlackCrit should become the framework for how this work should be discussed in the literature to raise awareness to state governments regarding Black folx's persistent lead poisoning, NYCHA's neglect and mass atrocity research as a long overdue advocacy effort to bring the necessary voice, authentic narrative, and actual knowledge of the lived experiences of Black families in NYCHA with lead poisoning.

The goal of this viewpoint/perspective paper should have two fundamental objectives (1) NYCHA and New York State accepting accountability for failing to address these preventable lead poisoning issues directly affecting Black children; and (2) offering the proper support and resources to help Black children sustain the best QOL trajectory possible when diagnosed with lead poisoning.

Lead poisoning research has never been approached through a mass atrocity and BlackCrit framework and perspective. This is the first report on bridging these fields within the context of NYCHA public housing neglect of lead-abatement and continued poisoning of current and future generations of Black children. This failure of NYCHA lead-abatement contributes annually to economic loss in New York State for many years to come which could be entirely avoided.