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Many of China’s older buildings, built in the 1970s and 1980s, faces several indoor temperature and heating energy consumption problems. Based on an investigation and analysis of an old hotel in Urumqi, this paper proposes a renovation plan to improve the indoor temperature and reduce the heating energy consumption, thereby introduce a sustainable development strategy for the winter. The effects of different renovation plans on the hotel were simulated using DesignBuilder and PVsyst software. The results show that improving the insulation performance of the building envelope, including reforming the roof, exterior wall, doors, and windows and adjusting the window-to-wall ratio, is the primary way to improve indoor temperature and reduce heating energy consumption in winter. If economic conditions allow, we can also install photovoltaic systems on the roof to save a significant amount of energy. This paper puts forth specific reconstruction plans for old buildings in cold regions as well as some possible reconstruction paths for other structures according to the local economic development level to provide a reference for future related studies.

Under carbon peaking and neutrality constraints, low-carbon retrofitting of residential buildings (LRRB) has become a strategic need for most countries worldwide. However, the development of China’s LRRB market still relies on government guidance without moving towards the goal of autonomous orientation. This area is still a concern for academics. Moreover, many stakeholders are involved in the LRRB, and the secondary stakeholders’ behavioral strategies do not substantially impact the LRRB. So, this paper adopts Mitchell’s score-based approach to identify the core stakeholders, followed by a tripartite evolutionary game model of government, ESCOs, and owners. Based on the system dynamics (SD) model, the evolution rules of the three parties’ behavior strategies and evolution stabilization strategies are analyzed, and the key factors influencing the equilibrium are found. The results of the study show that under the condition that the government adopts the same level of subsidy for ESCOs and owners, ESCOs are more sensitive to the subsidy; with the introduction of penalties under the premise of subsidy, ESCOs can reach evolutionary equilibrium faster; and when the benefits of owners accepting LRRB outweigh the losses, owners will eventually choose to accept retrofit regardless of whether the government subsidizes owners or not. Finally, the paper ends with suggestions for developing an LRRB market. The game model proposed in this paper can provide a scientific reference for stakeholders’ carbon reduction decisions.

Net-zero energy buildings (NZEB) have received widespread attention for their excellent energy and carbon reduction potential in various countries. However, relatively little research has been conducted on the life performance of its primary form: the ultra-low energy building (ULEB). This paper proposes an optimization method combining meta-models to investigate the carbon reduction potential of ultra-low energy buildings in severely cold regions of China. The XGBoost algorithm is used to construct a meta-model of building performance, and the grid search method is used to obtain a high-precision meta-model with an R2 of 0.967. Secondly, NSGA-II is used to find passive technical solutions based on the meta-model that minimize the global warming potential (GWP), global cost (GC), and operation energy consumption (OE). Finally, the variables affecting the life-cycle performance of buildings were ranked by sensitivity analysis. The results show that GWP, GC, and OE are reduced by 12.7%, 6.7%, and 7.4% compared with the original building through the optimization process proposed. Sensitivity analysis showed that for GWP, the top four sensitivities are window type (TW) > WWR of south wall (WWRS) > roof insulation thickness (IR) > WWR of north wall (WWRN). For GC, the top four sensitivities are: TW > WWRS > IR > WWR of west wall (WWRW); for OE, the top four sensitivities are: TW > IR > WWRS > WWRN. This paper’s optimization framework and research results can effectively guide the design of the ULEB in severely cold regions.

The high intensity of solar radiation and long sunshine time in the Turpan area lead to the necessity of sunshade construction. Sunshade components can effectively block direct solar radiation and the secondary heating of buildings. Through the analysis of the importance and sensitivity of sunshade components, it was found that the importance of sunshade components accounts for the largest proportion of multi-parameters, and the sensitivity of sunshade components accounts for about 60% of the total. At the same time, the change in sunshade length has an important influence on the proportion of air conditioning energy consumption and space comfort when the sunshade length reached the 0.6 m–0.8 m range. The energy consumption curve of air conditioning no longer decreased and tended to be horizontal, which showed that a sunshade could effectively reduce the energy consumption of air conditioning, while the PMV comfort curve gradually increased and tended to be horizontal, indicating that a sunshade could effectively improve indoor comfort; therefore, a sunshade could reduce direct solar radiation, reduce the energy consumption of air conditioning and improve indoor thermal comfort. In view of the extremely harsh climate characteristics of Turpan, although Turpan needs to carry out shading design, as a typical wind-sensitive component, the structural safety of the visor under the action of an extreme wind environment is the primary focus of designers. The design requires wind loads as control loads. Based on the ANSYS Workbench platform, this study used the fluid–structure coupling technology to calculate and solve for the wind load stress and strain of a horizontal sunshade and a vertical sunshade in a cantilevered external sunshade of different buildings orientations. In this study, by solving for the maximum principal stress and maximum principal elastic strain under 10 working conditions, the results showed that the maximum principal stress of the sun visor under all working conditions was 0.39 MPa, which is much smaller than the tensile strength of C25 concrete. The calculated maximum principal elastic strain of the sun visor was 0.12 × 10−4, which is much smaller than the maximum strain value of concrete. Therefore, the wind load under this research condition had no great influence on the structural safety of the concrete sunshade, which proves the structural feasibility of the building sunshade member in the Turpan area, and provides a reference for the future practical engineering of cantilever members in the Turpan area.

BackgroundPeople hospitalized with COVID-19 often exhibit hematological alterations, such as lower lymphocyte and platelet counts, which have been reported to associate with disease prognosis. It is unclear whether inter-individual variability in baseline hematological parameters prior to acute infection influences risk of SARS-CoV-2 infection and progression to severe COVID-19.MethodsWe assessed the association of blood cell counts and indices with incident SARS-CoV-2 infection and severe COVID-19 in UK Biobank and the Vanderbilt University Medical Center Synthetic Derivative (VUMC SD). Since genetically determined blood cell measures better represent cell abundance across the lifecourse, we used summary statistics from genome-wide association studies to assess the shared genetic architecture of baseline blood cell counts and indices on COVID-19 outcomes.ResultsWe observed inconsistent associations between measured blood cell indices and both SARS-CoV-2 infection and COVID-19 hospitalization in UK Biobank and VUMC SD. In Mendelian randomization analyses using genetic summary statistics, no putative causal relationships were identified between COVID-19 related outcomes and hematological indices after adjusting for multiple testing. We observed overlapping genetic association signals between hematological parameters and COVID-19 traits. For example, we observed overlap between infection susceptibility-associated variants at PPP1R15A and red blood cell parameters, and between disease severity-associated variants at TYK2 and lymphocyte and platelet phenotypes.ConclusionsWe did not find convincing evidence of a relationship between baseline hematological parameters and susceptibility to SARS-CoV-2 infection or COVID-19 severity, though this relationship should be re-examined as larger and better-powered genetic analyses of SARS-CoV-2 infection and severe COVID-19 become available.

With the need for a green economy and the introduction of low-carbon policies, more and more old buildings are being transformed to improve the thermal performance of buildings and reduce energy consumption. However, people ignore the village buildings and the old public buildings. Based on the investigation of a typical health center in Linyi City, this paper proposed improvement measures using EnergyPlus simulation software and JePlus parameter chemical tools. The various factors analyze the various parts of the enclosure, and the energy-saving effect of the roof is better than that of the exterior wall: When the thickness of the insulation layer gradually increases from 0 cm to 30 cm, the unit energy consumption of the building gradually decreases from 57 kW·h/m2 to 42.8 kW·h/m2, while that of the roof is gradually reduced to 24.41 kW·h/m2. Double exterior windows effectively reduce the energy consumption of the building in all renovation schemes. The optimal scheme is selected through the parameterized design of all the overall enclosure reconstruction schemes and the initial investments. The results showed that the investment recovery of the selected scheme was between 1.36–5.28 years. Plan 5 (12 cm XPS is used as insulation material for the exterior wall and roof, and the exterior window is replaced with 6 mm medium transmittance Low-e + 12 mm air + 6 mm clear) had the highest energy efficiency (91.11%). Plan 2 (6 cm XPS is used as insulation material for the exterior wall and roof, and the exterior window is replaced with 12 mm single medium transmittance heat-reflecting glass) had the shortest investment recovery period (2.04 years).

In recent years, energy consumption has continuously been increasing, and the energy consumption proportion in buildings has risen yearly. In order to promote the carbon-neutral goal of carbon peaking, the building sector realizes green and low-carbon transformation. This paper proposes a new type of solar flat plate collector with an additional transparent cover made by the ETFE film, which is tested for thermal performance under different environmental and operational parameters. The Ansys Fluent software was used to build a three-dimensional steady-state model of the collector, which can simulate the collector components’ temperature and the mass outlet temperature under the test conditions. The collector’s instantaneous heat collection efficiency curve fitted by comparing and analyzing the theoretical, experimental, and simulated data. The instantaneous efficiency intercept was 0.72, and the heat loss coefficient was 3.94 W/(m2·K). The results show that the collector efficiency of the ETFE film structure collector is 18.6% higher, and the heat loss coefficient is 27.3% lower than that of an ordinary collector under standard mass flow conditions.