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• The performance of building PV system were analyzed in Hainan province. • The potential of PV system used on building roof was investigated. • Carbon emission reduction during 2020–2060 was calculated. • This study would provide references for using PV system in Hainan province. Energy balance in the building industry and the potential of building PV systems are indispensable to achieve carbon peaks and carbon neutrality in Hainan Province. This research investigated load matching for different types of buildings and the electricity generation potential of building PV systems in Hainan Province. The tilt angle, orientation, PV conversion efficiency and available area of the building were adopted as research parameters to analyze the chance of realizing zero carbon in the building industry. The potential of roof PV systems and economic analysis in Hainan Province were studied. The results show that when a high-performance PV system (20%) is utilized, the electricity demand of buildings can be covered, and 86.9% of the total electricity demand of Hainan Province can be provided by roof PV systems. If all available roof area was used appropriately, carbon emission reduction is up to 13.49 million tons CO 2 every year. The cumulative carbon emission reduction could be 408.7 million tons CO 2 by using roof PV systems during 2020–2060. The initial cost and pay back period were 117.4 billion CNY and 6.3 years, respectively. All residential buildings, office buildings and small hotels are able to achieve an energy balance when the PV conversion efficiency is 20%. Electricity generation reaches the maximal value when the tilt angle is 15°. When the tilt angle is in the range of 0° to 30°, energy generation is larger than 270 kWh/m2a, and the difference is less than 5%. Electricity production on the east and west facades is greater than that on the south façade. This research provides some references for using building PV systems in Hainan Province. [ABSTRACT FROM AUTHOR]

Infrastructure construction results in transportation cost and regional economy changes. Based on the exogenous infrastructure change of a county highway opening as a natural experiment, this paper uses the spatial difference-in-differences (DID) model to analyze the impact of highway construction in three different provinces of China from 2004 to 2017. It was proved that highway connectivity had no significant or negative impact on the economy of the counties in three provinces that the highway passes through. In addition, highway connectivity was claimed to have obvious spatial spillover effects, which could promote the economic development of the whole region. For counties belonging to provinces in different regions and stages of economic development, we establish a spatial DID model that integrates time and space dimensions to study the impact of expressways on county economic development, to make up for the traditional DID model's dependence on SUTVA assumptions, and to obtain spatial spillover effects. [ABSTRACT FROM AUTHOR]

The application of air source heat pumps is mainly restricted by the outdoor ambient temperature, which causes poor application effects in the severe cold region of China. This paper proposes an innovative hybrid energy system of "solar air collector + air source heat pump + energy storage" that is utilized to save energy for ultra-low energy building in severe cold region. The feasibility and performance of this hybrid energy system is studied in Hailar which is located in severe cold region of China. The hybrid energy system is introduced and the dynamic characteristics of the key components of the system are analyzed in combination with the local meteorological conditions. The results indicate that, in Hailar, where the outdoor heating calculation temperature is lower than −30 °C and solar energy resources are not particularly abundant, the peak inlet air temperature of the air source heat pump increases by no less than 10 °C and the coefficient of performance of the system is expected to be higher than 3.0 under extremely low temperature conditions. Warm air from solar air collector can be supplied for heating without ASHP operation if its temperature is higher than 25 °C. These results provide some references for the application of the hybrid energy system in the severe cold region of China. • The hybrid system applied in the severe cold region of China has be proposed. • Performance of the hybrid system has be investigated deeply. • The hybrid energy system can be used for passive ultra-low energy building. • The temperature range of air source heat pump application is broadened. [ABSTRACT FROM AUTHOR]

The application of a photovoltaic (PV) system for zero energy buildings is crucial to balance energy consumption. This paper investigated the potential of PV systems for buildings in different climate zones of China. The tilt angle, orientation, plot ratio, PV conversion efficiency and location were selected to study their influences on electricity production. The performance of the PV system was analyzed based on a residential building, and employed RETScreen in combination with TRNSYS. The results indicate that southwest China is the best place to develop zero energy buildings. Low-rise residential buildings can realize zero energy in China when the PV conversion efficiency is higher than 20%. However, an energy balance only occurs in the southwest when the PV conversion efficiency is 10%. For different building heights, with a high conversion efficiency (20%), the energy consumptions rates are less than 15 kW h/m2a all over China. In the southeast, the effect of the building shape on energy generation can be ignored due to the high solar elevation angle in the summer. Although the optimal tilt angle varies for different cities, the energy deviations are less than 10% when tilt angle is within 10° of the optimal angle. This study proposed a formula to evaluate the potential of a building PV system. The maximum difference between the simulated and calculated results is approximately 10%, which is reasonable and acceptable. This paper provides some references for the application of PV systems in zero energy buildings. [ABSTRACT FROM AUTHOR]

The 3D engineering surfaces are considered as having a range of spatial frequency components including roughness, waviness and form. Before the characterization of a 3D engineering surface, filtering is done first to separate these different components. To overcome the shortcomings of the traditional filtering methods, this paper presents a shearlet-based separation method using high definition metrology (HDM) that has the ability to measure a huge number of data points to represent a 3D surface. The 3D engineering surface is decomposed into different sub-bands of coefficients with non-subsampled shearlet transform (NSST). Then the surface components at different levels are reconstructed by applying an inverse NSST on the shearlet coefficients and combined into the above three surface components. The performance of the proposed method is validated by both simulated surface data and real-world 3D surface data, and the results demonstrate that the proposed shearlet-based method is effective for the separation and extraction of different surface components. [ABSTRACT FROM AUTHOR]

Load matching is an inevitable problem that restricts the development of photovoltaic (PV) system used in buildings. The objective of this paper is to solve this problem by conducting a load matching assessment and optimization of PV system in different climate zones of China. The influences of the tilt angle, orientation, PV plot ratio and building height on the achievement of zero energy buildings (ZEBs) were evaluated. The PV potentials of roofs and facades were analyzed and optimized based on self-sufficiency and self-consumption. Net load variance and the maximum electricity import were employed as indices to evaluate the performance of PV systems in different climate zones of China. The results of the load matching assessment show that electricity generations from roof PV systems in low-rise buildings can meet most of the energy demand (at least 70%) in all climate zones of China. East and west facades of mid-rise buildings have an advantage over south façades in Kunming and Guangzhou in terms of load matching. It is necessary to combine roofs, south, east and west facades to meet the ZEBs requirement of for high-rise building. When the heating/cooling demand is dominant, the tilt angle should be higher/lower than the latitude of the specific location. This research will be helpful in designing building PV systems in different climate zones of China. Load matching analysis is helpful in designing building PV system in different climate zones of China. The results show that east and west facades of mid-rise buildings have an advantage over south façade in Kunming and Guangzhou. It is necessary to combine roof, south, east and west facades to meet the requirement of ZEBs for high-rise building. Image 1 • Load matching with PV system were analyzed for zero energy buildings. • PV potential were investigated based on self-sufficiency and self-consumption. • The optimal combinations of PV system were obtained in different climate zones. • East and west facades have advantages over south façade in Kunming and Guangzhou. [ABSTRACT FROM AUTHOR]

The combinatorial auction is one of the important methods used for multi-item auctions, and the solution to the winner determination problem (WDP) is the key factor in the widespread application of combinatorial auctions. This paper explores the use of the cross-entropy method to solve the WDP, which is an NP problem. The performance of the proposed approach is evaluated on the basis of two well-known benchmark test cases. The experimental results show that, compared with the genetic algorithm and the particle swarm optimization algorithm, the cross-entropy（CE）method has the advantages of a higher success rate and a shorter time for solving the WDP. Therefore, the CE method provides a high-quality solution for the effective solution of the problem of determining winning bids in combined auctions. [ABSTRACT FROM AUTHOR]

With the wide applications of face recognition techniques, spoofing detection is playing an important role in the security systems and has drawn much attention. This research presents a multispectral face anti-spoofing method working with both visible (VIS) and near-infrared (NIR) spectra imaging, which exploits VIS-NIR image consistency for spoofing detection. First, we use part-based methods to extract illumination robust local descriptors, and then the consistency is calculated to perform spoofing detection. In order to further exploit multispectral correlation in local patches and to be free from manually chosen regions, we learn a confidence factor map for all the patches, which is used in final classifier. Experimental results of self-collected datasets, public Msspoof and PolyU-HSFD datasets show that the proposed approach gains promising results for both intra-dataset and cross-dataset testing scenarios, and that our method can deal with different illumination and both photo and screen spoofing. [ABSTRACT FROM AUTHOR]

Previous studies show a decline in parent–child co-residence among the elderly. This study examined the effect of living away from adult children on upward intergenerational monetary transfers by analysing a 2006 survey of 19,947 persons aged 60 and above and selected from 20 provinces in China. Results indicate that elderly who were not co-residing but had at least one adult child living in another community/village within the city/county were likely to receive more intergenerational monetary transfers than those who were living with children. Living close to children, rather than co-residing with them, might be the primary living arrangement for older Chinese people in the foreseeable future. The findings have important programme and policy implications for countries such as China, which has the largest elderly population in the world. There is a strong need for the development of specific public care support systems focused on the elderly population, in general, and elderly in rural areas, in particular. [ABSTRACT FROM PUBLISHER]

• First time to measure microclimatic parameters before an intact tomb excavated. • Short variable phase in burial time is as short as 0.3 h. • Rapid variation of microclimate will trigger deteriorations of historical artifacts. • Local average annual temperature is the optimal preservation temperature. The development and utilization of urban underground space have contributed to more excavation of ancient tombs in recent years. The microclimate in the burial environment is crucial for the sustainability of historical artifacts. In this paper, the variation in thermal and humid conditions during the burial time from the closure of a tomb to excavation was investigated by field testing and computational fluid dynamics (CFD) modeling. The selected object is the famous M1 tomb chamber of the mausoleum Zhang An-shi, which has a 2000-year history. It was found that the average air temperature (T) and relative humidity (RH) of the M1 tomb chamber before excavation were 12.7 °C and 93.0%, respectively. The results of the CFD simulation suggest that the burial time of an ancient tomb consists of a very short variable phase and a long stable phase. The very beginning phase may be as short as 0.3 h. The dramatic changes in temperature and RH were more than 10 °C and 20%, respectively. Consequently, dramatic changes in the thermal and humid environment will trigger the deterioration of historical artifacts. Current findings further suggest that the local annual average temperature is optimal for the conservation of underground artifacts excavated from the soil thermostatic layer. This study paves the way for characterizing the environment of an ancient tomb chamber, as well as museum design, energy savings that support cultural heritage protection and preventive conservation. [ABSTRACT FROM AUTHOR]

• Effect of external venetian blind on nearly zero-energy buildings was studied. • Energy performance of external shading in different climate regions was quantified. • Multiple optimization design of shading arrangement parameters was discussed. • A new index was proposed for evaluating the energy efficiency of external shading. The development and promotion of nearly zero-energy buildings (NZEBs) is an inevitable trend of building energy conservation, and external venetian blind shading (EVBS) is one of the most effective technologies for NZEBs. Therefore, this study aims to analyze and optimize the energy-saving performance of EVBS for NZEBs in different climate regions of China. Based on EnergyPlus, the optimal shading arrangements of NZEBs are obtained by evaluating the shading performance of different shading slat angles, orientations, window-to-wall ratios (WWRs) and locations. The results show that the energy saving potential of EVBS for NZEBs is significant, especially in southwest of China. And the energy-saving trends of EVBS with different shading arrangements are similar regardless of the climates, and the maximum energy saving potential per unit window area of EVBS is obtained in slat angle of 0°, west orientation and low WWR. The total energy saving potential (P) gradually decreases first and then increases rapidly as the slat angle increases for all slat angle (0°~180°) shading conditions. And the multi-orientation shading effect is the sum of each single-orientation shading effect. In addition, the cooling efficiency index (CEI) is proposed to evaluate the importance of shading to reduce the cooling demand of buildings, and to guide the improvement of the self-performance of shading. This research will be helpful in guiding the application of EVBS for residential NZEBs in different climate regions of China. [ABSTRACT FROM AUTHOR]

Objective Scintigraphy using 99mTc-3PRGD2 targeting integrin αvβ3 could assess activation of hepatic stellate cells (HSCs). Liver fibrogenesis is intimately associated with activation of HSCs, and the fibrolytic process is accompanied by the reduction of the activated HSCs. In this study, we aimed to evaluate the feasibility of this method to assess the severity of liver fibrosis and the reversal after the fibrotic stimulus withdrawal. Methods Liver fibrosis of different stages was induced by thioacetamide (TAA) injection for 2, 4 and 6 weeks (n = 6 for each time point). Another 6 rats with 8-week TAA administration (the 8-week group) and 6 rats which were injected with TAA for 6 weeks, and then withdrawn of TAA for 2 weeks (spontaneous recovery rats, SRR) were designed. The ratios of radioactivity detected in the liver vs. the heart at 30 min post-injection of 99m Tc-3PRGD2 (L/H30 min ), the collagen proportionate area (CPA), the protein and mRNA levels of integrin α v , integrin β 3 were analyzed and compared among groups. Results The Ishak stage scores of the livers in the control and 2, 4, 6-week groups increased when the TAA administration period was extended. L/H30 min increased with the upgrading of liver fibrosis and the differences between each pair of groups were statistically significant ( p 30 min in the 8-week group was similar to that in the 6-week group ( p > 0.05), but was significantly higher than that in the SRR group ( p = 0.005). Conclusions Scintigraphy using 99m Tc-3PRGD2 may provide a non-invasive method for grading liver fibrosis and assessing liver fibrosis reversal. [ABSTRACT FROM AUTHOR]

Objective: Integrated positron emission tomography/magnetic resonance imaging (PET/MRI) scanners provide combined MR-based anatomic and metabolic image information. The aim of this study was to evaluate qualitative and quantitative diagnostic performance of PET/MR with (18)fluoro-2-deoxyglucose ((18)F-FDG) using a diagnostic MR sequence in patients with abdominal and pelvic tumors, compared to positron emission tomography/computed tomography (PET/CT). Materials and Methods: Forty five patients underwent a single-injection ((18)F-FDG), dual-imaging protocol including whole-body PET/CT and subsequent regional PET/MR hybrid imaging. A regional PET/MR scan followed the PET/CT. Images from both modalities were analyzed using a 3-point scale for PET/CT and PET/MR image quality, image alignment, and lesion visibility on PET images. PET-CT/PET-MR functional and anatomical correlation was analyzed. Results: A total of 66 lesions were studied, from which 63 were identified using PET/CT and 59 were identified using PET/MR. The (18)F-FDG PET images had good diagnostic quality (P<0.001); alignment was found to be excellent in PET/MR data as well as PET/CT data (P=0.102), and there was no difference in lesion visibility (P=0.18). The average rating score regarding anatomical correlation for PET-positive lesions was 2.75 for combined MR sequence images and 2.04 for CT, with a significant difference (P=0.317), Standard uptake value (SUV) for focal lesions had excellent correlation (SUVmax/mean: R=0.948/0.948); furthermore, the SUVmean of background organs combined, bone marrow and the muscle tissue showed good correlation (R=0.329/0.398/0.298). No correlations were found in the liver and spleen. Conclusions: PET/MR with diagnostic MR sequence was able to detect abdominal and pelvic lesions and had good image quality compared to PET/CT. SUVmax and SUVmean values in focal lesions, and the SUVmean of background organs generally correlated well in abdominal and pelvic oncology patients examined using PET/CT and PET/MRI. [ABSTRACT FROM AUTHOR]

Objective Hepatic stellate cell (HSC) activation, which is accompanied by increased expression of integrin αvβ3, is an important factor in liver fibrogenesis. Molecular imaging targeting the integrin αvβ3 could provide a non-invasive method for evaluating the expression and the function of the integrin αvβ3 on the activated HSCs (aHSCs) in the injured liver, and then provide important prognostic information. 99m Tc-3PRGD2 is such a radiotracer specific for integrin αvβ3. In this study, we aimed to compare the differences in liver uptake and retention of the 99m Tc-3PRGD2 between normal liver and injured liver to evaluate the feasibility of 99m Tc-3PRGD2 scintigraphy for this purpose. Methods We used planar scintigraphy to assess changes in integrin αvβ3 binding of intravenously-administered 99m Tc-3PRGD2 in the livers of rats with thioacetamide (TAA)-induced liver fibrosis compared with the controls. We co-injected cold c(RGDyK) with 99m Tc-3PRGD2 to assess the specific binding of the radiotracer. We performed Sirius red staining to assess liver fibrosis, immunofluorescent colocalization to identify the location of integrin αvβ3 expressed in the fibrotic liver, and we measured protein and messenger RNA expression of integrin αvβ3 and alpha smooth muscle actin (α-SMA) in the control and fibrotic livers. Results The fibrotic livers showed enhanced 99m Tc-3PRGD2 uptake and retention. The radiotracer was demonstrated to bind specifically with the integrin αvβ3 mainly expressed on the aHSCs. The liver-to-heart ratio at 30 min post-injection was higher in the fibrotic livers than in the control livers (TAA, 1.98 ± 0.08 vs. control, 1.50 ± 0.12, p < 0.01). The liver t 1/2 was longer than in the controls (TAA, 27.07 ± 10.69 min vs. control, 12.67 ± 4.10 min, p < 0.01). The difference of heart t 1/2 between the two groups was not statistically significant (TAA, 3.13 ± 0.63 min vs. control, 3.41 ± 0.77 min, p = 0.94). Conclusions 99m Tc-3PRGD2 molecular imaging can provide a non-invasive method for assessing activation of HSCs. [ABSTRACT FROM AUTHOR]

Objective: To clarify the usefulness of (18)F-FDG PET/CT for detecting primary gastric cancer via gastric distention using a mixture of milk and Diatrizoate Meglumine. Materials and Methods: A total of 68 patients (male: 47, female: 21; age: 41-87 years) suspected of gastric carcinoma underwent (18)F-FDG PET/CT imaging. After whole-body PET/CT imaging in a fasting state, the patients drank a measured amount of milk with Diatrizoate Meglumine. Local gastric district PET/CT imaging was performed 30 min later. The imaging was analyzed by semi-quantitative analysis, standardized uptake value (SUV) of the primary tumor was measured in a region of interest. The diagnosis results were confirmed by gastroscopy, pathology, and follow-up results. Results: Of the 68 patients, 56 malignant gastric neoplasm patients (male: 37, female: 19) were conformed. The sensitivity, specificity, positive predictive value and negative predictive value of fasting whole-body PET/CT imaging for a primary malignant tumor were 92.9%, 75.0%, 94.5%, and 69.0%, respectively. The values for distension with a mixture of milk and Diatrizoate Meglumine were 91.1%, 91.7%, 98.1%, and 68.8%, respectively. The area under the curve was 0.919 ± 0.033 and 0.883 ± 0.066 for the diagnosis of gastric cancer with SUVmax in a fasting state and after intake of mixture respectively, the differences were not statistically significant (P=0.359). Using gastric distension with a mixture of milk and Diatrizoate Meglumine, the mean ratio of the lesion's SUVmax to the adjacent gastric wall SUVmax increased significantly from 3.30 ± 3.05 to 13.50 ± 15.05, which was statistically significant (P<0.001). Conclusions: (18)F-FDG PET/CT imaging is highly accurate for the diagnosis of primary gastric carcinoma. Gastric distention can display the lesions more clearly, however, it cannot significantly improve diagnostic accuracy. [ABSTRACT FROM AUTHOR]

Objective: To clarify the usefulness of 18F-FDG PET/CT for detecting primary gastric cancer via gastric distention using a mixture of milk and Diatrizoate Meglumine. Materials and methods: A total of 68 patients (male: 47, female: 21; age: 41–87 years) suspected of gastric carcinoma underwent 18F-FDG PET/CT imaging. After whole-body PET/CT imaging in a fasting state, the patients drank a measured amount of milk with Diatrizoate Meglumine. Local gastric district PET/CT imaging was performed 30min later. The imaging was analyzed by semi-quantitative analysis, standardized uptake value (SUV) of the primary tumor was measured in a region of interest. The diagnosis results were confirmed by gastroscopy, pathology, and follow-up results. Results: Of the 68 patients, 56 malignant gastric neoplasm patients (male: 37, female: 19) were conformed. The sensitivity, specificity, positive predictive value and negative predictive value of fasting whole-body PET/CT imaging for a primary malignant tumor were 92.9%, 75.0%, 94.5%, and 69.0%, respectively. The values for distension with a mixture of milk and Diatrizoate Meglumine were 91.1%, 91.7%, 98.1%, and 68.8%, respectively. The area under the curve was 0.919±0.033 and 0.883±0.066 for the diagnosis of gastric cancer with SUVmax in a fasting state and after intake of mixture respectively, the differences were not statistically significant (P =0.359). Using gastric distension with a mixture of milk and Diatrizoate Meglumine, the mean ratio of the lesion's SUVmax to the adjacent gastric wall SUVmax increased significantly from 3.30±3.05 to 13.50±15.05, which was statistically significant (P <0.001). Conclusions: 18F-FDG PET/CT imaging is highly accurate for the diagnosis of primary gastric carcinoma. Gastric distention can display the lesions more clearly, however, it cannot significantly improve diagnostic accuracy. [ABSTRACT FROM AUTHOR]