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In recent years, the promotion of nearly zero-energy buildings (NZEBs) in China has emerged as a crucial step for the building industry in shifting towards a green and low-carbon future. Starting from scratch, the development of NZEBs in China has included the application and fundamental research, the compilation of national and local standards, and the rapid emergence of projects encompassing 23.89 million square meters nationwide. These efforts have yielded preliminary results in national standards, technology systems, technical roadmaps, and large-scale project demonstrations. However, challenges, including further reducing incremental costs, developing industries for retrofitting existing buildings into NZEBs, and expanding the range of policy incentives, remain to be addressed. This article provides an overview of the last decade’s progress in NZEBs in China, covering key technological research, policy development, engineering demonstrations, and the current industrial development status. Finally, the prospects of the NZEB industry are discussed.

Building air tightness increased quickly in recent years as nearly zero energy buildings concept gradually drawn more attentions from the industry. Ventilation system plays an important role for the indoor air quality control in residential buildings with good air tightness. The energy consumption of the ventilation system is a significant part of the overall energy consumption of low energy residential building. The influence of the building air tightness on the energy consumption of ventilation system was not addressed sufficiently in previous studies. This paper analyses the quantitative relations between building air tightness, energy recovery efficiency and ventilation system control strategy. A mathematical model of the heating and cooling energy consumption in residential buildings is proposed, which takes building air tightness, energy recovery efficiency and control strategy of ventilation system as major input parameters. Equivalent COP of ventilation energy recovery system is proposed as an energy efficiency index of the ventilation system. It can be used as a criterion to decide the optimal design parameters of nearly zero residential buildings in different climate conditions.

This paper studied the retrofit project of an existing office building in Beijing to meet the requirements of nearly zero energy buildings. The office building is the first retrofit nearly zero energy building project in China. There are technical difficulties under the constraints of the building and resources. In order to study the technical solutions applicable to the project, we analyzed the suitability of different energy-saving technologies based on the resources and characteristics of the project. Then we obtained the key energy-saving factors. This paper also discussed the energy saving effects of different energy efficiency technology solutions, proposing an optimized nearly zero energy technology solution and verifying the energy-saving level of the optimized plan. Compared with normal new constructions complied with national energy efficiency standard, the energy efficiency of this retrofit building increased by 60%.

This laboratory study explores the development of plastering mortar modified by feather fibers, so as to lay the groundwork for utilizing poultry feathers in thermal-insulation materials and removing them from waste streams. The laboratory testing measured the consistency value, porosity, compressive strength and thermal conductivity of various cement mortar mixes as a function of feather fiber dosage. The experimental data were used to determine the appropriate weight fraction of feather fibers in the mortars for thermal insulation. The results indicate that the incorporation of feather fibers decreased the consistency value of fresh mortar and increased the surface roughness and porosity of hardened mortar. Under the investigated conditions, as the content of admixed fiber increased, both the compressive strength and thermal conductivity of hardened mortar decreased remarkably before leveling off. The desirable dosage of feather fibers falls in the range of 0.2–0.7% by mass of dry mixture.

Accurate segmentation of the breast tissue is a significant challenge in the analysis of breast MR images, especially analysis of breast images with low contrast. Most of the existing methods for breast segmentation are semi-automatic and limited in their ability to achieve accurate results. This is because of difficulties in removing landmarks from noisy magnetic resonance images (MRI). Especially, when tumour is imaged for scanning, how to isolate the tumour region from chest will directly affect the accuracy for tumour to be detected. Due to low intensity levels and the close connection between breast and chest portion in MRIs, this study proposes an innovative, fully automatic and fast segmentation approach which combines histogram with inverse Gaussian gradient for morphology snakes, along with extended Stein's unbiased risk estimator (eSURE) applied for unsupervised learning of deep neural network Gaussian denoisers, aimed at accurate identification of landmarks such as chest and breast.

Existing literature increasingly identifies the effect of CEO passion on firm innovation. However, the understanding on how and when CEO passion promotes firm innovation remains limited. We examine the role of the top management team (TMT) creativity as the intervening mechanism in the link between CEO passion and firm innovation, and explore the different roles of flexibility-oriented and control-oriented cultures as contingencies. By using survey data of 245 firms in China, we find that flexibility-oriented culture positively moderates the relationship between CEO passion and TMT creativity, but negatively moderates the relationship between TMT creativity and firm innovation. By contrast, control-oriented culture negatively moderates the relationship between CEO passion and TMT creativity, and insignificantly moderates the relationship between TMT creativity and firm innovation. We also discuss our theoretical contributions and provide some practical implications., Author(s): Wenjun Cai [sup.1] , Jibao Gu [sup.1] , Jianlin Wu [sup.1] Author Affiliations: (1) grid.59053.3a, 0000000121679639, School of Management, University of Science and Technology of China, , 96 Jinzhai [...]

Existing research has established leadership antecedents of team voice behavior. However, the content of team voice has not been distinguished, and limited findings have been generated about the effect of relational leadership, leader-member exchange (LMX), on team voice. Drawing on conservation of resource theory, this research explores the unique and interactive effects of LMX mean and LMX differentiation on promotive and prohibitive team voice. Two multisource studies (Study 1: 293 members and 51 leaders; Study 2: 524 members and 90 leaders) have been conducted to examine the hypotheses. Both studies have revealed that LMX mean is positively related to promotive team voice, and LMX differentiation is negatively related to prohibitive team voice. In addition, LMX differentiation weakens the effect of LMX mean on prohibitive team voice. Study 2 has further verified that LMX differentiation strengthens the effect of LMX mean on promotive team voice. Findings have demonstrated the significant and complex influence of team LMX on team voice. We suggest that team leaders can improve LMX mean and reduce LMX differentiation to encourage team voice behavior., Author(s): Di Zhao [sup.1] , Jianlin Wu [sup.2] , Jibao Gu [sup.2] Author Affiliations: (1) grid.440718.e, 0000 0001 2301 6433, School of Business, Guangdong University of Foreign Studies, , 510420, [...]

Accurate segmentation of the breast region of interest (BROI) and breast density (BD) is a significant challenge during the analysis of breast MR images. Most of the existing methods for breast segmentation are semi-automatic and limited in their ability to achieve accurate results. This is because of difficulties in removing landmarks from noisy magnetic resonance images (MRI) due to similar intensity levels and the close connection to BROI. This study proposes an innovative, fully automatic and fast segmentation approach to identify and remove landmarks such as the heart and pectoral muscles. The BROI segmentation is carried out with a framework consisting of three major steps. Firstly, we use adaptive wiener filtering and k-means clustering to minimize the influence of noises, preserve edges and remove unwanted artefacts. The second step systematically excludes the heart area by utilizing active contour based level sets where initial contour points are determined by the maximum entropy thresholding and convolution method. Finally, a pectoral muscle is removed by using morphological operations and local adaptive thresholding on MR images. Prior to the elimination of the pectoral muscle, the MR image is sub divided into three sections: left, right, and central based on the geometrical information. Subsequently, a BD segmentation is achieved with 4 level fuzzy c-means (FCM) thresholding on the denoised BROI segmentation. The proposed method is validated using the 1350 breast images from 15 female subjects. The pixel-based quantitative analysis showed excellent segmentation results when compared with manually drawn BROI and BD. Furthermore, the presented results in terms of evaluation matrices: Acc, Sp, AUC, MR, P, Se and DSC demonstrate the high quality of segmentations using the proposed method. The average computational time for the segmentation of BROI and BD is 1 minute and 50 seconds.

An important step in implementing geospatial digital twins is to enhance the expressiveness of virtual geographical scenes for the physical world. However, the existing virtual geographical scenes cannot quickly express the dynamically changing geographic environment for remote users due to the inefficient handling of modeling processes, user perception, and remote sharing. The research analysed the concept and characteristics of geospatial digital twins, and constructed the virtual geographical scene ontology, based on which we developed geographical spatiotemporal semantic rules and designed a dynamic annotation algorithm to enhance the representation of virtual geographical scenes. Finally, we investigated a real-time transmission method of panoramic video based on 5 G and used immersive virtual reality (IVR) to realize the user experience of remote immersion in geographical scenes. We selected a specific geographic environment containing multiple typical geographic entities to develop three prototype systems for experimental analyses. The results showed that the proposed method enabled users to view the virtual geographical scene on a VR device. The average latency for this process was 14.72 seconds. Compared with the virtual geographical scenes constructed by traditional methods, the experiments showed the proposed method advantageous in comprehensiveness, timeliness, and photorealism and abilities to enhance the user's geographical scene perception. [ABSTRACT FROM AUTHOR]

Under the background of "dual carbon" development goals, the rapid expansion of internet data centers driven by advancements in 5G technology has led to increased energy consumption and elevated heat densities within the server rooms in these facilities. In this study, the modular data center is taken as the research object for the purpose of figuring out a way to improve the thermal environment of the computer room, reduce power consumption, and ensure the safe and stable running of servers. To this end, this study established an airflow organization model for the modular data center and verified this model through experimental methods. Computational Fluid Dynamics (CFD) simulations were employed to investigate the effects of raised floor height, floor opening rate, and cold/hot air channel closure on airflow organization. Furthermore, the efficiency of airflow organization was evaluated using entransy loss metrics. The results show that optimal airflow conditions are achieved when the height of the raised floor is 600–800 mm, the opening rate is 40%, and the combined opening is 40%. Additionally, the closure of either the cold channel or both the cold and hot channels significantly improves airflow performance. Specifically, cold channel closure is recommended for new data centers with underfloor air supply systems, while combined cold and hot channel closure is suitable for data centers with high power density and extended air supply distances. [ABSTRACT FROM AUTHOR]

The factors that influence graduate student creativity have drawn attention in higher education research. It is controversial whether leader-member exchange (LMX), here representing supervisor-student exchange relationship, can promote creativity. Previous studies on the LMX-creativity relationship have ignored the roles of negative psychological processes and personality differences. From the resource allocation perspective, we consider challenge stress and hindrance stress as the mediators and identify personal initiative (PI) as a moderator to examine the relationship between LMX and graduate student creativity. The results obtained from 576 Chinese samples confirm that LMX promotes graduate student creativity by reducing their hindrance stress; the interaction term between high PI and high LMX increases challenge stress. These findings support the importance of developing high quality supervisor-student exchange relationship for graduate students, adding their challenge stress, reducing their hindrance stress, and cultivating their PI so as to improve their creativity., Author(s): Di Zhao [sup.1] , Jianlin Wu [sup.1] , Jibao Gu [sup.1] Author Affiliations: (1) grid.59053.3a, 0000000121679639, School of Management, University of Science and Technology of China, , 96 Jinzhai [...]