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When renewing building facades in most Chinese cities, covers are often designed and installed to conceal the outdoor units of residential split air conditioners for congruousness of building facades. However, how those covers impact airflow and energy efficiency should be thoroughly examined. This study investigates two popular designs of cover (louver and circular-hole) and selects Nanjing, renowned for its hot summers, as the case city. This study employs Computational Fluid Dynamics models to simulate airflow obstruction caused by the covers surrounding the outdoor units. Grey Model, trained from the CFD results, quantifies interactions between design of cover and inlet air temperature. Additionally, a thermodynamic model assesses the covers' impact on the coefficient of performance of air conditioners. The findings reveal that the primary cause of outdoor unit overheating is warm air backflow from the outlet to the inlet. A mere 1 °C increase in inlet air temperature can reduce COP by 4.1%–8.7%. The maximum temperature differences caused by different designs of cover are 4.5 °C for the louver type and 4.4 °C for the circular-hole type. To mitigate these negative impacts, optimal design recommendations are provided: a minimum distance between the cover and outdoor unit of 0.29 m for louver type and 0.1 m for circular-hole type, both feasible in most installations. These findings can help designers, manufacturers, installers and policymakers, to facilitate the design and installation of optimal covers for outdoor air-conditioning units, thus minimizing energy efficiency losses.

Urban energy-efficient retrofit is an important path to reduce energy consumption and carbon emission. However, balancing environmental and economic benefits and making choices among numerous retrofit packages is challenging for decision-makers. This study proposes a data-driven framework that integrates physical UBEM and machine learning model to evaluate the energy retrofit performance of urban building clusters and assists decision-makers in rapidly selecting the optimal energy-efficient retrofit packages through NSGA-II. The feasibility of the proposed framework is validated using the building clusters of Sipailou campus in Southeast University as a case study and identified 25, 19, and 13 optimal retrofit packages for office, public and education building clusters that minimizes the total energy consumption and carbon emissions while maximizing economic benefits from 343 retrofit packages of each cluster in a 30-year retrofit period.

Background: Both Wood's lamp and reflective confidential laser scanning microcopy are helpful for the diagnosis and treatment of vitiligo. However, there is few research that contains large samples and consistent observations. Aims: To analyze the characteristics of Wood's lamp images and reflectance confocal microscopy (RCM) images of vitiligo lesions and to evaluate their significance in vitiligo staging. Methods: We analyzed the characteristics of RCM images, Wood's lamp images, the vitiligo disease activity (VIDA) score, and clinical features to guide vitiligo staging and treatment. Results: The expert consensus based on the clinical features, VIDA score, Wood's lamp findings, and isomorphic response was consistent with the Wood's lamp findings (χ2 = 3.63, p > 0.05) and RCM findings (χ2 = 3.60, p > 0.05) in diagnosing vitiligo and assessing the disease stage. There was a correlation between the three lesion grades based on the Wood's lamp findings and the stage of vitiligo (p < 0.01). Lesions that appeared porcelain white under the Wood's lamp were in the slowly progressive stage; lesions that appeared gray‐white or trichromatic under the Wood's lamp were in the rapidly progressive stage; lesions with clear borders under the Wood's lamp needed further analysis by RCM for the stage to be determined; lesions with blurred borders under the Wood's lamp were in the rapidly progressive stage; lesions that were visible under the naked eye and under the Wood's lamp were in the rapidly progressive stage. Conclusion: The study demonstrates a reliable correlation between the findings of RCM (a sophisticated expensive tool) and Wood's lamp examination (a simple, readily available, inexpensive tool) in the assessment of the disease activity of vitiligo lesions. [ABSTRACT FROM AUTHOR]