Extreme heat poses growing challenges to age-friendly renewal in older residential neighborhoods, where compact urban form, aging infrastructure and a large elderly population often coexist. Nearby streets frequently support daily mobility and access to local services, making their thermal usability particularly important for elderly. However, existing assessments often focus on environmental performance without fully translating behavioral and microclimatic evidence into renewal priorities. This study proposes and applies a behavior-informed street-level thermal resilience assessment framework as a pre-design screening tool. Using two aging neighborhoods in Xi’an, China, as empirical cases, the framework integrates questionnaire surveys, map-assisted route identification, 24-hour street-canyon monitoring, pedestrian-level micrometeorological measurements and multi-scale morphological analysis. Results show that neighborhood streets were the most frequently reported outdoor activity spaces, selected by 66% of respondents, while 78% regarded sidewalks as the hottest or most sun-exposed spaces. Street-canyon Temperature–Humidity Index (THI) exceeded the “very hot” threshold for 21–24 hours, and Universal Thermal Climate Index (UTCI) remained above 32°C throughout daytime monitoring and exceeded 38°C for 8–9 h. Shaded microsites exhibited UTCI values up to 6.3°C lower than the exposed microsites, primarily in association with lower mean radiant temperature. Morphological associations were generally context-sensitive, with the most robust relationships observed between surrounding green coverage and daytime humidity. The study provides an initial empirical application of a structured screening approach for identifying behaviorally relevant streets, critical periods, potential thermal protection gaps and directions for subsequent detailed assessment.
Light perception is a fundamental aspect of human sensory experience and lighting a key element of building design. However, light’s effect goes beyond vision - illuminance is the primary external driver of melatonin suppression. The discovery of intrinsically photoreceptive retinal ganglion cells (ipRGCs) shifted attention toward spectral composition beyond the simple 3 cone model. The 24‐hour solar cycle remains the benchmark, providing strong midday suppression, mild evening suppression, and no suppression at night. Advances in LED technology have enabled dynamic lighting systems to replicate these non‐visual effects. However, despite extensive work, energy efficiency, in particular, melanopic efficacy, has not been addressed—a critical omission given the demand for sustainable, cost‐effective building solutions.Spectral power distributions were synthesized utilizing combinations of commercial LED strips, including warm‐white (WW), ice‐blue (IB), cool‐white (CW), cyan, and RGB, with the three objectives: (1) maximize melanopic illuminous efficacy (for daytime lighting), (2) maximize melanopic efficacy of luminous radiation (m-ELR) tunability, and (3) maximize photopic illuminous efficacy at low m-ELR(for evening lighting); under the constraint of high colour fidelity (CRI > 95, Duv|<0.001, CCT<6500 K).Results show that a four‐LED system (WW, IB, red, green) achieves high melanopic illuminous efficacy (daytime), broad m‐ELR tunability, and strong photopic illuminous efficacy at low m‐ELR. Incorporating Cyan LEDs offered negligible gains. Amber extended the m‐ELR range for improved nighttime performance. Considering the North American Electrical Codes (96 W/circuit maximum) and simplicity of installation, we recommend a streamlined three‐strip configuration (WW, IB, RAG) for 24 hr dynamic white lighting.
Accurate prediction of turbulent flow within urban canopies is essential for microclimate assessment and pollutant dispersion. While Large-Eddy Simulation (LES) is well-suited to capture these highly three-dimensional, unsteady turbulent structures, its sensitivity to numerical setups often necessitates extensive, case-specific calibrations. To overcome this methodological fragmentation, the present study establishes a transferable LES configuration and evaluates it across both aligned and staggered cube arrays. As a recommended baseline, the guidance adopts a non-conformal nested grid, the dynamic Smagorinsky–Lilly subgrid closure, the Werner–Wengle wall function, second-order bounded central discretization, and synthetic-vortex inflow turbulence. The framework further standardizes grid evaluation by adopting the resolved energy spectrum and LESIQ index as explicit verification metrics, combined with strict flow-through time requirements for initialization and sampling. Resolution analysis shows that the simulations resolve more than 85% of the turbulent kinetic energy across the full domain and more than 95% within the core region. Comparisons with multiple wind-tunnel and numerical datasets show good agreement for both mean velocities and higher-order turbulence statistics. Applying this validated baseline, the fixed configuration captures the transport regimes of the two arrays, with longitudinal, channeling-dominated exchange in the aligned case and sweep-dominated vertical exchange in the staggered case, confirming its transferability across topologically distinct urban morphologies.
