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A data-driven heuristic for the dynamic vehicle routing problem with multiple soft time windows
Get PDFIn the Dynamic Vehicle Routing Problem with Multiple Soft Time Windows (Dynamic VRPMSTW), customer requests arrive in real time and must be scheduled within flexible service intervals. This problem is complicated by operational constraints, such as vehicle capacities, travel durations, and heterogeneous fleets, which make it difficult for classical optimization methods to adapt quickly to changing conditions. Following recent trends in contextual optimization, we propose a Data-Driven Dynamic Heuristic that integrates Artificial Neural Networks for predicting travel times and demands into a Dynamic Hybrid Adaptive Large Neighborhood Search (DD-Dynamic HALNS). Using cluster assignment and genetic crossover operators, the method generates high-quality initial solutions and continuously re-optimizes them as new requests emerge, ensuring adaptability and service reliability. The effectiveness of the proposed method is evaluated on real-world logistics data and benchmark instances. Results from real-world delivery operations demonstrate an average distance reduction of 11.6% compared with the current solution, with further improvements up to 15.5% when a 10-minute time window flexibility is introduced. These findings highlight the practical benefits of integrating predictive analytics with heuristic optimization, leading to improved cost efficiency, reduced operational constraints, and enhanced service reliability.</p
Ten questions on indoor greening and environmental quality
Get PDFWhile outdoor urban greening is recognised for its benefits, indoor green infrastructure (iGI) in shaping indoor environmental quality (IEQ) - including air quality, thermal comfort, and bioaerosols - remains underexplored. This ten-question paper identifies key challenges, opportunities, and research gaps in the iGI-IEQ nexus, organised under 10 questions across five thematic clusters: (1) biophysical and technical performance; (2) ecological and microbiological dynamics; (3) human health and wellbeing; (4) equity, access, and socio-economic factors; and (5) implementation and systems integration. Findings indicate that iGI can improve air quality, regulate humidity, and enhance thermal comfort. However, its performance depends strongly on plant density, species selection, and ventilation. Most evidence comes from controlled settings. iGI may offer positive psychological and cognitive benefits, and can reduce health inequalities through affordable indoor interventions. However, significant data scarcity exists for long-term field studies, indoor microbial ecosystem effects, and socio-economic accessibility. Widespread adoption of iGI requires quantification of proven benefit conditions, followed by overcoming technical, operational, and regulatory barriers via adaptive design, digital monitoring, and interdisciplinary collaboration. As a culminating synthesis, this study introduces a newly developed comprehensive matrix that classifies twenty-six indoor greening types across twenty IEQ parameters, incorporating an assessment of current data confidence. This matrix lays a foundational framework for informed decision-making and design guidance. This review offers evidence-based insights for researchers, policymakers, and practitioners to effectively leverage iGI where suitable, in creating healthier, climate-resilient residential and commercial buildings, addressing both immediate IEQ challenges and supporting long-term sustainability objectives.</p
What are the experiences of fulfilling Care Act 2014 duties for social workers in mental health settings?
No full textTowards a Patient Specific Computational Model of Coronary Flow, Myocardial Perfusion, and Ventricular Mechanics
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Investigation of Non-Inductive Bifilar Pancake SFCL Losses in Electric Aircraft Cryogenic Propulsion
Get PDFSuperconducting powertrain is critical for nextgeneration electric aircraft, allowing for lossless power transmission and significantly increasing efficiency, performance, and range. A superconducting fault current limiter (SFCL) is a device on the DC side that uses superconducting materials to control excessive current during faults, thereby protecting the powertrain and enhancing system stability. Among several superconducting fault current limiters (SFCLs), resistive SFCLs (R-SFCLs) have benefits such as compactness, lightweight, high reliability, and a fail-safe nature. When subjected to alternating magnetic fields or currents, superconducting materials exhibit hysteresis, eddy currents, and flux flow effects, which lead to energy dissipation and reduced efficiency. This also applies to RSFCLs operating under normal conditions in the superconducting state, where AC losses occur and require appropriate thermal management to mitigate heat generation and prevent unexpected quenching. DC current ripple and its harmonic contents in an R-SFCL cause additional losses, increasing joule heating and potentially driving the superconductor out of its superconducting state, reducing its efficiency and fault-limiting capability. This research was conducted from two perspectives: theoretical calculations and experiments. The objective is to study the losses in the R-SFCL within the superconducting system, including ripple and harmonic effects, and to determine the design parameters of the R-SFCL cooling system to minimise thermal impacts
The Impact of Inter-Departmental Distance on Joint Sales in Retail Stores
Get PDFWe find that inter-departmental distance between two departments in a store can significantly impact joint (combined) sales of that pair. Using data from blueprints and sales across 64 stores for 52 weeks, along with an experimental study to test our theorizing, we find a curvilinear (inverted U-shaped) relationship between inter-departmental distance and joint sales. Specifically, close departments are perceived to be substitutes, decreasing the likelihood of buying products from both departments. As distance increases, departments are perceived as somewhat related but different, increasing their diversity and the likelihood of buying from both departments. As distance between departments becomes large and products are seen as unrelated, the likelihood of buying from both departments decreases. This relationship is moderated when departments have non-identical layouts and when there are larger variety differentials across departments. Accordingly, we determine an optimal store layout using BARON solver by maximizing total store revenue. Our results suggest an increase in weekly revenue of about 4.08% for supermarkets (range of -.67% to 9.50%) and 3.20% for hypermarkets (range of .82% to 8.5%). While strategic locations of departments can help retailers increase overall sales, prior empirical work has not studied the impact of distance between departments at the store level
Large-amplitude periodic solutions to the steady Euler equations with piecewise constant vorticity
Get PDFWe consider steady solutions to the incompressible Euler equations in a two-dimensional channel with rigid walls. The flow consists of two periodic layers of constant vorticity separated by an unknown interface. Using global bifurcation theory, we rigorously construct curves of solutions that terminate either with stagnation on the interface or when the conformal equivalence between one of the layers and a strip breaks down in a (Formula presented.) sense. We give numerical evidence that, depending on parameters, these occur either as a corner forming on the interface or as one of the layers developing regions of arbitrarily thin width. Our proof relies on a novel formulation of the problem as an elliptic system for the velocity components in each layer, conformal mappings for each layer, and a horizontal distortion, which makes these mappings agree on the interface. This appears to be the first local formulation for a multi-layer problem, which allows for both overhanging wave profiles and stagnation points.</p
Fabrication and characterization of taste-masked core-shell nanofibre mats for dual drug delivery of antihypertensives in pediatrics
Get PDFDrug adherence in pediatrics can be challenging due to bitter drug taste, dysphagia and polypharmacy. With pediatric hypertension on the rise worldwide, this study investigated the use of electrospinning to create a novel taste-masked, fixed-dose combination of lisinopril dihydrate (LIS) and amlodipine besylate (AML) for paediatric use. Electrospun nanofibres of the antihypertensives were formulated as core–shell fibres with polyvinylpyrrolidone (PVP), and Eudragit® EPO (EEPO) by applying an electrical charge to a viscous mixture of the drugs, polymers and solvents. The drug loading, release kinetics, morphology, thermal analysis, physical and solid-state characterization of the fibre mats were evaluated. Taste-masking was investigated in vitro by electronic-tongue analysis. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses showed smooth, non-beaded core–shell fibres with diameters in the nanorange. Fourier transform infra-red (FTIR) spectroscopy and x-ray diffraction (XRD) studies confirmed the drugs were amorphously dispersed within the fibres and thermal analysis studies showed acceptable stability profile of the formulations. Both drugs were over 90 % released in 15 mins consistent with immediate release formulations. The e-tongue mean sensor response plot showed the nanofibre mats achieved a statistically significant enhanced taste-masking (p < 0.0001) compared to raw amlodipine which registered a high bitterness reading of 87 mV. This study therefore indicates that coaxial electrospinning may be used to produce a fixed-dose taste masked nanofibre mat of LIS and AML that can potentially be used to improve adherence in children.</p
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