Artiles
Open Access
Article
07 May 2026Research on Trajectory Generation Method for Multi-Objective Optimization of Thrust Vector Vehicle in Constrained Space
Thrust-vectoring UAVs can realize decoupling of position and attitude compared with conventional quadrotors due to the ability to change thrust direction, and are used to perform various complex indoor and outdoor missions. However, existing trajectory generation frameworks are mostly for quadrotors with fixed thrust direction and a coplanar surface, and do not consider the dynamics of thrust-vectoring UAVs. To address this, this paper proposes a multi-objective trajectory generation method for thrust-vectoring UAVs in constraint space. By parametrically modeling the constraint space, the method considers the effects of environmental boundary constraints and platform dynamics characteristics on the collision constraints and motion decoupling of the trajectory, and comprehensively optimizes the trajectory’s indicators of stability, speed, and safety to plan the states and input actions of the flight trajectory. Meanwhile, a trajectory generation evaluation system is proposed, given that compared with the conventional quadratic objective function, the proposed method is effective in reducing the attitude change of the trajectory, improving the rapidity and safety, in which $$L_{\theta}$$ and $$L_{r i s k}$$ are reduced by 70.4% and 19.1%, respectively. Meanwhile, by comparing with the conventional quadrotor, the advantages of the thrust-vectoring in decoupling motion are quantified, especially in reducing the attitude change during flight, the pitch angle of the generated trajectory is reduced from ±30° to within ±20° degrees, which exerts the motion decoupling advantages of the thrust-vectoring.
Open Access
Article
06 May 2026Dispersion During Underground Hydrogen Storage in Depleted Gas Reservoirs
Dispersion in porous media is a multiscale process that governs the distribution and mixing of fluids in the subsurface. In underground hydrogen storage, dispersion is particularly critical due to hydrogen’s low molecular weight and large density contrast relative to natural gas. In addition to this, cyclic operations amplify mixing and transport effects beyond what is typically observed during conventional gas injection and storage. The apparent mixing observed during storage arises from the combined influences of localized dispersion, heterogeneity-driven channeling, and gravity segregation. Distinguishing between local, echo, and transmission dispersion provides a start for understanding reversible and irreversible components of mixing, and for connecting localized processes with field-scale performance. This study develops a systematic method to quantify dispersion in hydrogen storage within depleted gas reservoirs by combining analytical solutions of the convective–diffusive equation with multidimensional numerical simulations. The approach translates concentration fields into effective dispersion coefficients using different methods for mixing-zone length analysis. This enables evaluation across different permeability distributions, anisotropies, and spatial correlation lengths. The method is applied under both linear and radial flow conditions, including cyclic injection and production, to capture the distinct roles of gravity segregation, heterogeneity, and boundary conditions. Across the studied cases, the effective dispersion coefficient increases from approximately 1.03 to 3.5 m2/day as the Dykstra–Parsons coefficient increases from 0.3 to 0.9. Gravity segregation significantly alters plume evolution, reducing effective mixing zone lengths and introducing asymmetric displacement behavior. Under cyclic radial injection–production, incomplete plume reversal leads to persistent concentration halos, indicating irreversible mixing. The ratio of echo to transmission dispersion further quantifies the degree of irreversibility in the system. This work establishes a quantitative framework for characterizing dispersive transport in hydrogen storage systems and provides a basis for evaluating storage performance and reversibility under realistic subsurface conditions.
Open Access
Perspective
06 May 2026Eyewitness Memory: A Plea for a Detailed Study of Social Influence at Encoding
The evaluation of eyewitness memories has benefited greatly from basic memory research, which has shown that suggestive information or misinformation presented by a social source after an event can create substantial memory biases in participants’ memory, or even completely fabricated false memories. However, possible social influence occurring already at the stage of encoding (during the event) has so far been widely neglected. In basic research, meanwhile, several studies address this issue specifically with regard to incidental encoding of information (non-intentional encoding “along the way”, as it also occurs in eyewitness memories). The studies demonstrate that the social context at encoding influences how stimuli are encoded, and in one case even supports the occurrence of rich and detailed false memories. There are still many differences between the laboratory studies performed so far and any conceivable real-life scenarios of eyewitness situations. However, based on the results, it seems highly promising to evaluate the actual relevance of these initial findings for forensic science by modifying the paradigms to better reflect social encoding contexts that more closely resemble typical real-life eyewitness situations.
Open Access
Review
06 May 2026Recycling of Post-Consumer Cotton Waste
This review aims to address the environmental issues associated with the textile sector and explores innovative and optimal approaches for the zero-waste recycling of post-consumer cotton waste. The textile industry can transition toward a circular economy by implementing various recycling techniques. This will significantly cut the waste and raw material consumption, while promoting sustainability and environmental responsibility in textile manufacturing and consumption practices. This study focuses on several key techniques, including producing carbon fibres from waste, which provides a sustainable alternative to petroleum-based precursors. In addition, the regeneration of viscose fibres is achieved by chemical recycling of cotton waste and enzymatitc recycling. Method of Gasification and Thermochemical Valorisation, ioncell process is also discussed, emphasizing its potential to encourage resource conservation and lessen dependency on virgin resources. It also explains how cellulose nanofibrils (CNFs) can be extracted from post-consumer textiles and utilised to produce high-performance materials. Additionally, despite difficulties in preserving fibre quality, the potential of mechanical recycling techniques to yield viable yarns from recycled fibres is investigated.
Open Access
Communication
30 April 2026Peculiarities of Radiation Synthesis of MeWO4 Ceramics
We report the results of MeWO4 ceramics synthesis by the direct exposure of metal (Mg, Ca, Zn, W) oxides mixture to a high-power flux of high-energy electrons. The oxide powder particle sizes are 1–10 microns. The synthesis occurs with high efficiency in less than 1 s without the use of any additional substances and energy sources. The purpose of this work is to establish the main processes that ensure the effective synthesis of MgWO4, CaWO4, and ZnWO4 ceramics from ZnO, CaO, MgO, and WO4 oxides, which differ significantly in their physical and chemical properties. It has been found that the dependence of synthesis efficiency on the electron beam power density and the power density threshold at which synthesis begins varies significantly for simple metal oxides and is very close for the tungstates of these metals. The most probable explanation for the observed effect is redistribution of absorbed radiation energy. WO3 powder particles have a high absorptance of the incident electron radiation. The result is a cascade multiplication of primary electrons into secondary electrons with much lower energy. Secondary electrons are efficiently absorbed by MgO, CaO, and ZnO particles, leading to their efficient decomposition and the formation of a new phase.
Open Access
Article
30 April 2026Spatial and Temporal Changes in Shifting Cultivation in Mizoram: Drivers and Implications
Shifting cultivation is a way of life and the major source of livelihood in Mizoram, Northeast India. More than 80% of the rural population traditionally practices shifting cultivation. Since production is largely subsistence-oriented, a significant proportion of people live below the poverty line. This study aims to examine the spatial and temporal changes in shifting cultivation, identify the major drivers influencing it, and analyze its implications for the economy and environment. Data were primarily collected from satellite imagery for four years—2009, 2014, 2019, and 2024—during February and March, which is the period of burning Jhum plots. The data were analyzed using Geographical Information System (GIS) tools, and changes in the area under shifting cultivation were calculated using the exponential growth rate. The study reveals that between 2009 and 2024, the area under shifting cultivation declined by more than 80%. The major factors affecting the decline of shifting cultivation were assessed. These factors were climate variability and change, shortened Jhum cycles, reduced production and productivity, increasing population, higher levels of education, inadequate markets, and greater availability of jobs. Land degradation, reduction of biological diversity and gene pool, and food insecurity were also identified as significant implications. Transforming Jhum plots into permanent agricultural land could make farming practices more sustainable and improve livelihoods.
Open Access
Article
29 April 2026Advances in Smart Structures Using Control Algorithms for Sustainable Manufacturing
This paper presents developments in the intelligent control of smart structures for sustainable manufacturing. This study aimed to develop advanced control approaches for the intelligent control of piezoelectric structures and suppression of oscillations. A significant achievement is the development of advanced-control algorithms. Robust control techniques, such as H-infinity control, guarantee system performance and stability in the face of uncertainties and disruptions. The addition of white noise and uncertainty to advanced finite element models is a novel aspect of this study. The outcomes of the analysis were used to present the advances made using this method. This approach is innovative because it employs intelligent control strategies that consider construction optimization by reducing the oscillations and measurement noise. By accounting for modeling uncertainty, these methods optimize construction. Optimizing smart structures makes them more sustainable and ideal for practical applications. The proposed construction is sustainable and creates an innovative design for civil and mechanical engineering applications.
Open Access
Article
29 April 2026Family Factors and Children’s Academic Performance: The Mediating Role of Anxiety and the Moderating Role of Student Type
Family-related factors have been consistently linked to children’s academic performance and may also be associated with academic outcomes through psychological processes. Based on this perspective, the present study investigated the association between different family factors (parental involvement, parenting styles, and family functioning) and academic performance among Chinese primary school children. In addition, the potential mediating role of anxiety was examined, as well as whether the associations between these family factors and anxiety differed by student type (students with low versus typical school performance). Data were collected through a cross-sectional survey of 1083 students in Grades 3–5 and their parents from three primary schools in China, with parental involvement, parenting styles, family functioning, and children’s anxiety assessed via parent-reported questionnaires, along with measures of academic performance. The results showed that parental involvement, parenting styles, and family functioning were each significantly associated with children’s academic performance, and that anxiety played an indirect role in these relationships. Student type did not significantly moderate the relationship between these family factors and anxiety. Overall, the findings highlight the relevance of both the family environment and children’s anxiety in understanding variations in academic performance, and they suggest the importance of considering family- and child-related factors in educational research.
Open Access
Article
29 April 2026Design of an Industrial Facility for Recycled Polymer Granule Production
With the global increase in the production and disposal of polymeric waste, it becomes crucial to develop sustainable solutions that promote the circular economy of recyclable materials. This work presents a technical feasibility study for the implementation of a production unit for recycled polymer pellets, using a mixture of High-Density Polyethylene (HDPE), Low-Density Polyethylene (LDPE), and Polypropylene (PP) as raw material. The proposal aims to map the complete production process, from the collection and receipt of the recycled material to the granulation and sale of the pellets, including the characterization of the materials and the necessary compatibilizers and additives. The definition of production capacity, equipment selection, and industrial layout will also be addressed. The study includes a logistical and financial analysis, even if preliminary, for a hypothetical organization located in the region of São José dos Pinhais—PR, for the processing of recycled PP-PE blend. To carry out this study, basic concepts of industrial engineering design were applied. Information on the process and characteristics of a hypothetical PP-PE formulation was obtained through bibliographic research. The study allowed for important considerations regarding the development of a basic industrial design for processing recycled polymer. Preliminary results indicate existing demand in the metropolitan region of Curitiba (southern Brazil) and potential for job creation, including the use of labor from waste pickers distributed throughout the region.
Open Access
Article
28 April 2026Framing the ‘Double Burden’: A Critical Policy Discourse Analysis of the Climate-Poverty Nexus in the World Bank’s CCDRs for LDCs
Climate change and poverty are intertwined global challenges that disproportionately impact Least Developed Countries (LDCs). However, how global institutions discursively construct the climate-poverty nexus to legitimize their policy recommendations remains underexplored. Drawing on Critical Policy Discourse Analysis (CPDA), this study investigates how the World Bank Group frames the relationship between climate change and poverty in its Country Climate and Development Reports (CCDRs) for LDCs, as well as the discursive legitimation strategies embedded in these constructions. Findings identify two dominant, complementary discursive frames: the vulnerability frame and the causality frame. The vulnerability frame constructs poor and marginalized groups as passive victims of climate impacts, leveraging on attributive relational and passive material processes, and deploys moral evaluation as a legitimization strategy to position adaptation policies as a non-negotiable moral imperative. In contrast, the causality frame positions climate change as an active, causal agent driving poverty dynamics, utilizing active material processes and extended causal chains, and employs scientific rationalization to legitimize mitigation policies as rational, long-term investments aligned with LDCs’ development priorities. These two frames collectively shape a hybrid policy agenda that integrates ethical imperatives with technocratic efficiency, reflecting the World Bank’s attempt to legitimize its institutional influence on LDC climate-development trajectories. This research contributes to the scholarship on discourse in global climate governance by equipping stakeholders to engage with international policy advice critically and fostering more context-sensitive strategies for LDCs.
