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This paper takes an old office building in Hefei as the research object to explore the influence of the thermal buffering performance of the case building buffer space on the air speed and thermal environment of the office space based on the field measurement and simulation. As the thermal buffer layer of the main space, the buffer space is the layout mode that follows the thermal transfer law. Building buffer space variables were evaluated and compared by orthogonal tests to determine the better combination of buffer space sizes. The results show that when the air speed is taken as the evaluation index, the influence of each buffer space on the indoor environment is ordered: courtyard > corridor > foyer; when the temperature is taken as the evaluation index, the influence of each buffer space on the indoor environment is ordered: courtyard > foyer > corridor. From the perspective of green transformation, this paper selects two better schemes. Through comparison, it is found that when the buffer space size is: corridor (16 m × 2 m × 3.3 m), courtyard (16 m × 12 m) and foyer (7.2 m × 6 m × 3.3 m) is the optimal scheme, the indoor air speed is increased by 0.1 m/s, and the temperature is reduced to 27.0 °C, which is within the thermal comfort range of the human body. It is found that optimizing the buffer space size of the case building can effectively improve its indoor air speed and thermal environment, and provide theoretical basis and reference for the green transformation of existing buildings of the same type in this area. [ABSTRACT FROM AUTHOR]

With the development of urban built-up areas, accurately extracting the urban built-up area and spatiotemporal pattern evolution trends could be valuable for understanding urban sprawl and human activities. Considering the coarse spatial resolution of nighttime light (NTL) data and the inaccurate regional boundary reflection on point of interest (POI) data, land surface temperature (LST) data were introduced. A composite index method (LJ–POI–LST) was proposed based on the positive relationship for extracting the boundary and reflecting the spatial-temporal evolution of urban built-up areas involving the NTL, POIs, and LST data from 1993 to 2018 in this paper. This paper yielded the following results: (1) There was a spatial-temporal pattern evolution from north-east to south-west with a primary quadrant orientation of IV, V, and VI in the Hefei urban area from 1993–2018. The medium-speed expansion rate, with an average value of 14.3 km2/a, was much faster than the population growth rate. The elasticity expansion coefficient of urbanization of 1.93 indicated the incongruous growth rate between the urban area and population, leading to an incoordinate and unreasonable development trend in Hefei City. (2) The detailed extraction accuracy for urban and rural junctions, urban forest parks, and other error-prone areas was improved, and the landscape connectivity and fragmentation were optimized according to the LJ–POI–LST composite index based on a high-resolution remote sensing validation image in the internal spatial structure. (3) Compared to the conventional NTL data and the LJ–POI index, the LJ–POI–LST composite index method displayed an extraction accuracy greater than 85%, with a similar statistical and landscape pattern index result. This paper provides a suitable method for the positive relationship among these LST, NTL, and POI data for accurately extracting the boundary and reflecting the spatial-temporal evolution of urban built-up areas by the fusion data. [ABSTRACT FROM AUTHOR]

Strong diurnal variation of aerosol has been observed in many heavy polluted regions in China. This variation could alter the distribution of the direct aerosol radiative forcing (DARF) during the whole daytime that could increase the uncertainty of the normally used averaged values To quantify the effect of using the daily averaged DARF, 196 days of high temporal resolution ground-based data collected in SKYNET Hefei site during the period from 2007 to 2013 is used to perform an assessment. We demonstrate that strong diurnal changes of heavy aerosol loading have an impact on the 24 h averaged DARF when daily averaged optical properties are used to retrieve this quantity. Though there is a high temporal sampling of aerosol properties to be used for calculation of daily averaged ones, statistical errors (up to 5.3Wm-2 absolutely and 14.6% relatively) in the computed DARF still occur. These errors increase with increasing daily aerosol optical depth (AOD) is also found which indicated the high temporal resolution DARF dataset should be used in the model instead of the normal daily-averaged one, especially under heavy aerosol loading condition. [ABSTRACT FROM AUTHOR]

Sunken green space is one of the urban rainwater collection facilities, which belongs to Low Impact Development (LID) techniques. It plays a key role in the construction of sponge city, and the amount of runoff collection is usually affected by the area of the sunken green space, the infiltration rate of the soil, and the annual runoff collection rate. To determine the minimum soil infiltration rate of sunken green space considering the annual runoff collection ratio of sponge cities, this paper selects a residential district in Hefei city, China, as the case study. Based on 45 years of precipitation data, the designed rainfall corresponding to annual runoff collection ratios of 75%, 80% and 85% is 21.3 mm, 23.4 mm and 27.5 mm, respectively. The characteristics of rainfall infiltration in sunken green space are analyzed by using the water balance model and runoff yield and conflux model. The results reveal that the soil infiltration rate is 1.16×10−4 cm/s~3.88×10−3 cm/s when the sunken depth is 0.1 m~0.3 m and that the ratio of green space area is 5%~25%. The runoff collection of the reconstructed sunken green space is 2.87 times and 1.98 times that of the nonsunken green space and the nonreconstructed sunken green space, respectively. That is to say, under the comprehensive performance of the sunken depth, sunken green space area, the steady soil infiltration rater of the reconstructed sunken green space cannot be less than the value obtained in this paper. Otherwise, the requirements of annual total runoff reduction ratio of the sponge city cannot be met. Therefore, this study provides references for realizing the ratio of annual runoff collection and sponge city construction in similar urban areas. It can also be applied to optimal selection of sunken green space in some sponge city projects. [ABSTRACT FROM AUTHOR]

In multi-criteria group decision-making (MCGDM) problems with incomplete fuzzy preference relations (FPRs), the consistency based on bounded rationality is preferred to depend on the historical preferences of decision makers to generate complete FPR matrices. There are two factors in influencing the effect of historical preferences on complete FPR matrices and further decision makers' satisfaction of group solutions. One is the effectiveness of historical preferences and the other is their relative weights. On this basis, this paper proposes a new MCGDM method with FPRs based on the filtration-and-weighting-based triangular bounded consistency (FWBTBC), where historical FPRs between three adjacent pairs of alternatives are characterized by triangles and these two factors are considered comprehensively. A triangle filtration process is designed based on the Grubbs criterion to filter the abnormal triangles in the collected ones. A weight determination process is developed, where a distance measure between remaining triangles is constructed to calculate their weights. Based on the combination of the two processes, the FWBTBC of FPRs is created and then the proposed method is presented. The validity of the proposed method is demonstrated by its application in analyzing a drainage tube supplier selection problem for a tertiary hospital located in Hefei, Anhui, China. [ABSTRACT FROM AUTHOR]

The general population's assessment and perception of a city can be influenced by its skyline, which is one of its representatives. This paper uses semantic segmentation and exploratory factor analysis to conduct a study from two different perspectives, aiming to analyse the development and current situation of the skyline of Hefei's political and cultural new district. By collecting pictures of the skyline of the New Administrative and Cultural District, the New Administrative and Cultural District of Hefei's skyline is being studied for overall changes using the semantic segmentation method, and to evaluate the quality of the skyline in various years, the entropy weight–TOPSIS is employed. Through the literature investigation and creation status of the new political and cultural district, the index system is scientifically formulated to conduct a questionnaire survey, and its reliability and validity are tested. This study is conducted with exploratory factor analysis of factors that are vital in the city skyline. The results of this study show that (1) after the semantic segmentation of the pictures, it is found that the proportion of buildings and the proportion of vegetation are both rising; the proportion of buildings tends to level off after 2018, and the proportion of vegetation shows a uniform increase. In the relative proximity ranking, the overall trend is increasing, and the skyline is ranked first in 2024. (2) Two variables were identified based on the findings of the exploratory factor analysis: 'skyline value' and 'neighbourhood ecological quality'. The results of this study show that the skyline of Hefei's New Administrative and Cultural District in 2024 is the best overall, and that the skyline of the New Administrative and Cultural District has developed into one of the city images of Hefei, and that its optimisation can be considered in terms of the "quality of the surrounding ecological environment". [ABSTRACT FROM AUTHOR]

This study aims to apply performance-based safety-assessment methods to the monitoring and numerical simulation of excavation engineering projects in order to comprehensively enhance engineering risk management and decision support. In this paper, a deep excavation project in Hefei with thick silty clay layers was studied. The analysis included the surface settlement, the deformation of support structures, the vertical and horizontal displacements of pile tops, axial forces in steel braces, settlement, and the horizontal displacement of a gravity retaining wall on the south side of the excavation using field-monitoring data. A refined three-dimensional finite element model was established to further analyze the distribution of uplift displacement at the bottom of the excavation, horizontal displacement, and bending moments of piles based on simulation results. The research findings indicate that phased excavation can reduce the spatial extent of disturbance to the surrounding soil caused by excavation. Additionally, the closer the location to the excavation and the thicker the underlying silty clay layer, the faster the rate of settlement change and the greater the surface settlement. The spatial structure formed by steel braces and pile foundations effectively reduced the horizontal displacement of the engineering piles. The study's use of field monitoring and finite element simulation provided valuable insights into the deformation of support structures and the response of the surrounding soil to excavation, confirming the rationality and applicability of the support structure in this paper. The proposed method can serve as a reference for similar complex stratum excavation design and construction. The performance-based safety assessment is introduced, and the monitoring data, numerical simulation results, and performance targets are comprehensively analyzed to provide a reliable scientific basis for engineering decision making. [ABSTRACT FROM AUTHOR]

The construction of an urban metro will inevitably involve deep excavation. Risk assessment before deep excavation, risk reduction measures, and real-time monitoring during excavation can effectively ensure the safety of deep excavation. Taking the deep excavation pit of Lingbi Road Station of Hefei Rail Transit Line 8 as the research object, this paper first analyses and evaluates the self-risk, groundwater risk, and surrounding environmental risk of the deep excavation pit, and gives the corresponding measures to reduce the risk of the deep excavation pit. Then, the monitoring content of the excavation process is determined according to the environment of the excavation, the hydrogeological conditions, and the type of supporting structure, and the monitoring scheme is designed. Finally, the entire excavation process is monitored in real time. By analyzing the monitoring data of 13 projects, such as horizontal displacement of the wall top, axial support force, groundwater level, etc., it is found that the monitoring values of 13 projects do not exceed the control value. This proves that the composite internal bracing structure of the underground diaphragm wall is suitable for deep foundation pit support in the Hefei area, as the selection of the water-bearing deep foundation pit support structure, the value of the support structure parameters, and the design of the foundation pit dewatering scheme are all reasonable. The study of this paper also serves as a case reference for the support design of water-bearing deep excavation of subway station in Hefei area. [ABSTRACT FROM AUTHOR]

This paper aims to analyse how to effectively protect and scientifically utilize the natural enemies of Pentatomidae in tea plantations in the peak period. In this paper, the spatial, quantitative and temporal relationships between Pentatomidae and its natural enemies in "Pingyangtezao", "Wuniuzao", "Huangshandayezhong", "Anjibaicha","Longjing 43″ and "Nongkangzao" tea gardens in Hefei, China were comprehensively compared and analyzed with the methods of geostatistical analysis, gray system analysis and temporal ecotone overlap index analysis. According to the size of the closeness index, the top three natural enemies with the largest sum of spatial, quantitative, and temporal closeness indexes in the six tea gardens were Clubiona japonicola (X7, 16.514), Oxyopes sertatus (X5, 16.390) and Xysticus ephippiafus (X2, 16.270). The size of the ratio between the number of Pentatomidae individuals and natural enemies largely determines whether the natural enemies follow Pentatomidae pests closely or not. The better the growth of tea plantations and the richer the diversity of pest species, the more accurately the predation preference of natural enemies can be reflected. In the control of Pentatomidae, specific analysis should be made according to the occurrence characteristics of target pests in different tea plantations and the basic attributes of tea plantations (species, growth, population characteristics of natural enemies and pests, etc.) in order to scientifically utilize its natural enemies. [ABSTRACT FROM AUTHOR]

The existing prediction methods have complex model application, high requirements for data parameters, and are limited to the prediction of a single observation point. To address this problem, this paper proposes a deep learning-based surface subsidence prediction method. Taking Hefei City of China as the research area, the time-series surface deformation results of this area are obtained by using SBAS-InSAR, and then the SFLA intelligent algorithm and Elman neural network model are combined to predict the surface deformation of key urban areas, and the prediction results are compared and analyzed.The experimental results show that the prediction model proposed in this paper can not only accurately predict a single deformation point, but also predict regional land subsidence, and can be used for auxiliary decision-making of urban spatial planning, early warning of geological hazards and hazard mitigation. [ABSTRACT FROM AUTHOR]

Urban land subsidence is one of the important limiting factors for urban development, and strengthening the monitoring of urban surface subsidence contributes to long-term urban planning and construction needs. As a subcentral city in the Yangtze River Delta region of China, it is particularly important for Heifei to enhance the monitoring of surface subsidence. In this study, the persistent scatterer interferometric synthetic aperture radar (PS-InSAR) and small baseline subset (SBAS) techniques were used to process 139 scenes of Sentinel-1A SAR satellite ascending orbit data covering the central urban area of Hefei from July 2015 to July 2020, obtaining subsidence information for the region. The results show that the overall urban area of Heifei is relatively stable, but there are certain deformation trends in local areas. Four regions with obvious deformation were selected for the in-depth analysis of their deformation time series. The experimental study in this paper demonstrates that the PS-InSAR and SBAS techniques can achieve the accurate monitoring of large-scale ground subsidence in urban areas, ensuring the safety of buildings and their surrounding environments, and providing information support for urban security maintenance monitoring. [ABSTRACT FROM AUTHOR]

This paper proposes a novel aviation CO 2 emissions reduction method by introducing a market-based incentive mechanism. An aviation carbon emissions prediction model is proposed to characterize both the microscopic flight dynamics and the macroscopic air traffic demand trend. Based on emissions prediction, a linear climate response model is applied to evaluate the environmental impact of the aviation carbon emissions. Finally, a market-based framework for aviation CO 2 emissions reduction is established based on a two-phase carbon trading model, which provides a piecewise charge method through emission taxation and cap-and-trade. A case study is carried out to demonstrate the effectiveness of the proposed framework using a real-world dataset from the Hefei Air Traffic Control Zone in China. Three scenarios are defined to describe the possible development speed of sustainable aviation fuel application in the future: not applied, medium-speed development, and high-speed development. The results show that the carbon peak will be reached in 2025 in the high-speed development scenario, when the emission amount and associated environmental impact will be reduced by 23.7% and 22.3%, respectively. Thus, the market-based framework proposed in this paper can effectively reduce aviation CO 2 emissions and mitigate the effects of global warming. • An aviation CO 2 emissions prediction model is proposed considering both microscopic flight dynamics and macroscopic traffic demand. • A more efficient market-based CO 2 emission reduction framework is developed based on a two-phase carbon trading model by means of taxation and cap-and-trade. • Case study shows that the proposed method has a more optimal incentive for CO 2 emission reduction. [ABSTRACT FROM AUTHOR]

Due to the complications in the measurement of fine particulate matter (PM2.5), this paper proposes a method using lidar for assessing PM2.5. By calculating the aerosol optical depth (AOD) for MODIS, CALIPSO, and ground-based lidar, the corrected PM2.5 was predicted. The results showed that AOD and PM2.5 had a linear relationship. The linear correlation coefficient between ground-based lidar AOD and PM2.5 was 0.81, and the root-mean-square error (RMSE) and mean deviation (MD) were 24.43 and 18.41, respectively. The linear correlation coefficient between CALIPSO AOD and PM2.5 was 0.8, and its RMSE and MD were 42.91 and 33.25, respectively. The linear correlation between AOD and PM2.5 for VIIRS was approximately 0.7. This paper provides more possibilities for lidar observation and prediction of the environment. [ABSTRACT FROM AUTHOR]

Accurately forecasting the demand of urban online car-hailing is of great significance to improving operation efficiency, reducing traffic congestion and energy consumption. This paper takes 265-day order data from the Hefei urban online car-hailing platform from 2019 to 2021 as an example, and divides each day into 48 time units (30 min per unit) to form a data set. Taking the minimum average absolute error as the optimization objective, the historical data sets are classified, and the values of the state vector T and the parameter K of the K-nearest neighbor model are optimized, which solves the problem of prediction error caused by fixed values of T or K in traditional model. The conclusion shows that the forecasting accuracy of the K-nearest neighbor model can reach 93.62%, which is much higher than the exponential smoothing model (81.65%), KNN1 model (84.02%) and is similar to LSTM model (91.04%), meaning that it can adapt to the urban online car-hailing system and be valuable in terms of its potential application. [ABSTRACT FROM AUTHOR]

Hefei, the capital city of Anhui Province, China, has been experiencing rapid development due to fast population growth and continuous city expansion since 2010. The Hefei government began to operate the subway system in 2017 and introduced the concept of transit-oriented development (TOD) as a strategy to reduce traffic pressure and environmental pollution. By 2020, there were 77 TODs in operation. However, some TODs could not attract enough public transport passengers or increase the economic activities. This study analyzed the Hefei City TOD network and tried to identify TODs that need development priority among the existing TODs to guide the efficient allocation of resources for the development of the TOD network. First, this study measured the accessibility and activity intensity at each TOD by using the node–place model. Second, the 77 existing TODs were divided into 4 priority levels by applying the silhouette method. Level 1 and level 2 TODs have development priority and are referred to as "Unstable TODs" and "Unbalanced TODs," respectively. Finally, this paper provides some strategies for developing these priority TODs. [ABSTRACT FROM AUTHOR]

Land use/cover change (LUCC) detection and modeling play an important role in global environmental change research, in particular, policy-making to mitigate climate change, support land spatial planning, and achieve sustainable development. For the time being, a couple of hybrid models, such as cellular automata–Markov (CM), logistic–cellular automata-Markov (LCM), multicriteria evaluation (MCE), and multicriteria evaluation–cellular automata–Markov (MCM), are available. However, their disadvantages lie in either dependence on expert knowledge, ignoring the constraining factors, or without consideration of driving factors. For this purpose, we proposed in this paper a new hybrid model, the logistic–multicriteria evaluation–cellular automata–Markov (LMCM) model, that uses the fully standardized logistic regression coefficients as impact weights of the driving factors to represent their importance on each land use type in order to avoid these defects but is able to better predict the future land use pattern with higher accuracy taking Hefei, China as a study area. Based on field investigation, Landsat images dated 2010, 2015, and 2020, together with digital elevation model (DEM) data, were harnessed for land use/cover (LUC) mapping using a supervised classification approach, which was achieved with high overall accuracy (AC) and reliability (AC > 95%). LUC changes in the periods 2010–2015 and 2015–2020 were hence detected using a post-classification differencing approach. Based on the LUC patterns of the study area in 2010 and 2015, the one of 2020 was simulated by the LMCM, CM, LCM, and MCM models under the same conditions and then compared with the classified LUC map of 2020. The results show that the LMCM model performs better than the other three models with a higher simulation accuracy, i.e., 1.72–5.4%, 2.14–6.63%, and 2.78–9.33% higher than the CM, LCM, and MCM models, respectively. For this reason, we used the LMCM model to simulate and predict the LUC pattern of the study area in 2025. It is expected that the results of the simulation may provide scientific support for spatial planning of territory in Hefei, and the LMCM model can be applied to other areas in China and the world for similar purposes. [ABSTRACT FROM AUTHOR]

With the rapid development of the economy, the air quality is facing increasingly severe pollution challenges. The air quality is related to public health and the sustainable development of the environment of China. In this paper, we first investigate the changes in the monthly air quality index data of Hefei from 2014 to 2020. Second, we analyze whether the Spring Festival factors lead to the deterioration of the air quality index according to the time sequence. Third, we construct an improved model to predict the air quality index of Hefei. There are three primary discoveries: (1) The air quality index of Hefei has obvious periodicity and a trend of descent. (2) The influencing factors of Spring Festival have no significant effect on the air quality index series. (3) The air quality index of Hefei will maintain a fluctuating and descending trend for a period of time. Finally, some recommendations for the air quality management policy in Hefei are presented based on the obtained results. [ABSTRACT FROM AUTHOR]

In nature, expansive soil is generally in a state of swelling during rainfall, and its soil–water characteristic curve (SWCC) exhibits a three-dimensional space shape under the action of an increasing void ratio. In this study, expansive soil from Hefei, China, was used. SWCC and hygroscopic tests were performed. A three-dimensional hygroscopic swelling mathematical model of the dry density–void ratio–saturation degree was constructed based on the volume change behavior of expansive soils resulting from the hygroscopic test. In addition, depending on the variation in suction with the saturation degree of expansive soil under different values of dry densities, an SWCC mathematical model considering the swelling effect was constructed. The three-dimensional surface model of the hygroscopic swelling of the expansive soil was steeper in the lower saturation degree area. As the saturation degree increased, the three-dimensional surface gradually became flat. The SWCC model of the expansive soil under the action of swelling in a three-dimensional space is an S-shaped surface. The model exhibited dynamic changes in the suction and saturation degrees as the dry density of the soil decreased continuously. The model comprehensively revealed the hydraulic and swelling properties of expansive soil. [ABSTRACT FROM AUTHOR]

Driven by the concept of landscaping, this paper analyzed the impact of plant diversity on landscaping function, arrangement methods and community structure by taking plot sampling method as the experimental axis and 3 urban parks in Hefei as the blueprint. Six plots with the size of 20 m x 20 m were selected for investigation. There were 56 species of plants belonging to 50 genera and 42 families in the plots of Zhongshan Road City Park, 48 species of plants belonging to 44 genera and 40 families in the plots of Four Seasons Flower Sea City Park, and 69 species of plants belonging to 57 genera and 45 families in the plots of Xiaoyaojin Park. The survey results show that there are following problems in city parks: lack of plant effectiveness, too homogeneous plant community, disharmony between landscape and environment, poor plant maintenance and lack of attention to ecological maintenance. Based on this, the optimization measures are put forward: increasing evergreen plants to avoid no scenery in autumn, developing plants with excellent landscape effects and a variety of colorful plants, paying attention to the shaping of spatial structure and landscape pattern, regularly taking care of plants and their surrounding environment. It is expected to provide some reference for the construction and development of Hefei city parks, ensure the healthy and stable development of city parks, and provide ideas and methods for the improvement of plant landscaping in city parks. [ABSTRACT FROM AUTHOR]

The aim of this paper is to clarify the difference of spatial closeness between natural enemies and Frankliniella intonsa, and to provide a scientific basis for rational protection and utilization of natural enemies. This paper applied the block‐sample square difference analysis method, Gray correlation degree method, the aggregation intensity index method and ρ index method to study the difference in the closeness of the spatial relationship between F. intonsa and natural enemies when the number of F. intonsa and their natural enemies was the highest and the minimum area occupied by F. intonsa individuals and colonies in five tea plantations in Hefei, Anhui province in 2021 and four tea plantations in 2020. The results were as follows: 1) Tetragnatha squamataKarsch, Xysticus ephippiafus, Erigonidium graminicolum and Theridion Octomaculatum were the top four natural enemies closely related to F. intonsa in 2021. The top three natural enemies closely related to F. intonsa in 2020 were Tetragnatha squamata Karsch, Xysticus ephippiafus and Theridion Octomaculatum. Two years ago, Tetragnatha squamata Karsch and Xysticus ephippiafus were the same. 2) Cluster size did not change the distribution patterns of natural enemies and F. intonsa. 3) The aggregation of F. intonsa was caused by their own causes or some environmental factors, and the aggregation of natural enemies was caused by environmental factors. 4) In 2021, the minimum area occupied by individuals and groups of F. intonsa in tea gardens was 2m2, and in 2020, it was 8 m2. [ABSTRACT FROM AUTHOR]

With the increasing aging and the accelerating urbanization of China, the layout of urban medical facilities should be adjusted to meet the needs of the elderly population. This paper takes Hefei, China, as the research object. A questionnaire survey was conducted on the elderly who went to different levels of medical facilities for daily medical treatment, and 2,271 valid questionnaires were collected. The survey found that an accessibility factor of medical facilities is a common concern for the elderly who go to facilities of different levels, which indicates that it is reasonable to optimize the layout of medical facilities at all levels from the perspective of accessibility. Results revealed that the elderly in Hefei considered living within 10 km from a tertiary hospital (referred to as a Grade A facility in this paper) was most ideal. Meanwhile, a primary or secondary hospital (a Grade B facility) was most accessible within 6 km, and within 1.5 km was the optimum accessibility distance for a community health service center (a Grade C facility). This study considered the aforementioned medical service radii suitable for the elderly. From this, the study evaluated the accessible service range of different levels of medical facilities suitable for the elderly through the network analysis in ArcGIS. Then, the scarce areas of medical services in the city could be determined. Through location–allocation models, it was found that to realize the ideal medical distance for the elderly, 2 additional facilities were needed for Grade A, 1 for Grade B, and 61 for Grade C. The results could provide references for subsequent urban medical construction and aging development in China. [ABSTRACT FROM AUTHOR]

There are many advantages of reasonably determining the affected zone and its construction sequence for the multiline parallel pipe-jacking construction, such as convenient to reasonably arrange the pipeline section distribution mode, reducing the construction safety risk, and construction difficulty. Combined with the engineering construction practice of the multiline parallel pipe-jacking project for the north city drainage and flood control project through Chu River in Hefei, the strength reduction method has been utilized to study the surrounding stratum FOS for the pipe-jacking construction unloading under different overburden thickness Hs, different clear distance D, and different river water depth H w in this paper. The formula of the minimum critical overburden thickness Hsmin and the minimum critical clear distance Dmin of the surrounding stratum self-stability during pipe-jacking construction unloading have been derived. The division method of the affected zone for the multiline parallel river-crossing pipe-jacking construction which behaves as the mutual influence nonself-stability zone, the mutual influence self-stability zone, and the no mutual influence self-stability zone has been proposed. For further discussion, the construction sequence of the multiline parallel river-crossing pipe jacking has been studied. [ABSTRACT FROM AUTHOR]

In this paper, we investigate a technology to change the method and principle of n+ a‐Si:H etching from conventional dry etch to the innovative wet etch in TFT LCD fabrication. The technology is based on the development of a new wet metal etching solution and the design of the thinnest film thickness of a‐Si:H in the industry, combined with the etching process development, to achieve the etching of two different film layers of metal and N+ a‐Si:H in the back channel of TFT switches in one‐ step(Abbreviated as NW process). The process can effectively improve the capacity of Dry Etch process (Skip N+ Dry Etch); improve the uniformity of back channel a‐Si:H Remain (16.3%‐ >7.6%); improve product characteristics (Dark I on（ TFT working current） 5.5‐>6.0); improve yield (Yield rate↑0.3%).The process has been successfully developed for the first time in Wuhan BOE and has been widely used for batch products, meanwhile, the process has been extended to Hefei BOE and Fuzhou BOE, and other BOE line sites are also actively exploring the experiment. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Beijing University of Civil Engineering & Architecture is the property of Journal of Beijing University of Civil Engineering & Architecture Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The accumulated historical data are beneficial for generating solutions that are more satisfactory to decision makers because their preferences and experience are characterized by historical data. However, this might be infeasible when only few data are available. Suppose that the few data are collected from a domain called the target domain. There may be some domains correlated to the target domain, which are called source domains. The data from source domains might be useful for helping generate solutions to the problem in the target domain. Following this idea, this paper proposes a cross-domain decision making method based on the combination of TrAdaBoost, an instance-based transfer learning method, and a decision making method in the context of the evidential reasoning approach. This may be the first attempt to combine transfer learning with a decision making method to help generate high-quality solutions satisfactory to decision makers when only few data are available for the problem in the target domain. A data selection strategy is designed to increase the similarity between the data from source and target domains and a weight initialization strategy is designed based on the available gold standards. The two strategies are intended for improving the performance of the proposed method. With the two strategies, the process of the proposed method is presented. The effectiveness of the proposed method is validated by its application in helping diagnose breast lesions with the diagnostic data of five radiologists collected from a tertiary hospital located in Hefei, Anhui, China. [ABSTRACT FROM AUTHOR]

For the demand of rapid monitoring of pollution gas disorganized emissions in industrial parks, this paper studies the solar fast tracker system of vehicle-mounted SOF-FTIR (Solar Occultation Flux Fourier Transform Infrared Spectroscopy) system, where the spectrometer directly measures the broadband absorption spectrum of solar radiation light. A fast portable solar tracking system based on PSD (position sensitive detector) is designed, the mathematical model of solar spot position on the PSD surface source is established, and the optimal optical design parameters are simulated using the model. The dead-zone integral separation PID (Proportion Integration Differentiation) control algorithm is used to track the trajectory of the solar, and the light spot position model is used to nonlinearly compensate the output of PID control so that the PID controller has the same control precision and response speed in different error areas. Experimental analysis of the solar tracking performance of the vehicle-mounted SOF-FTIR under static and dynamic conditions, as well as the spectral effects on the measurements under static vehicle, constant speed, and turning driving conditions. The remote sensing application experiment of vehicle-mounted SOF-FTIR pollution gas emission flux was carried out in a tire factory in Hefei City, Anhui Province. A vehicle-mounted SOF-FTIR system realized the qualitative and quantitative analysis of the pollution gas at the boundary of the tire plant and calculated the flux of each component pollution gas. The emission flux of pollution gas was highly consistent with the actual pollution distribution of the tire plant. The results show that the positioning accuracy of PSD in the vehicle tracking experiment can also meet SOF-FTIR requirements for solar tracking. The remote sensing system will be useful in the field of atmospheric environment monitoring, and the mobile monitoring of regional pollutant gases based on solar infrared spectroscopy has application value. [ABSTRACT FROM AUTHOR]

Ground surface ozone (O3) is an emerging concern in China due to its complex formation process. In August 2020, field measurements of O3, NOx, and volatile organic compounds (VOCs) were carried out in Hefei's western suburbs. The pollution features of VOCs and O3 formation were thoroughly analyzed. The total VOC concentration was 42.26 ppb, with the dominant contributor being oxygenated VOCs (OVOCs). Seven emission sources were recognized using the positive matrix factorization (PMF) model, including aged air masses, combustion sources, fuel evaporation, industrial emissions, vehicular emission, solvent utilization, and biogenic emission. Ozone generation mainly occurred under an NOx-limited regime based on the zero-dimensional box model analysis. According to the scenario analysis, the 13% cut in O3 might be achieved by the 10% and 30% reduction in NOx and VOCs, respectively. The O3 budget analysis demonstrates its high ozone production rate during the pollution period. The influence of regional transport cannot be ignored for high O3 pollution. This paper provides scientific evidence for O3 production and the strategies of reducing O3 by controlling its precursors. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Yangtze Normal University is the property of Journal of Yangtze Normal University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

X-band weather radar can provide high spatial and temporal resolution data, which is essential to precipitation observation and prediction of mesoscale and microscale weather. However, X-band weather radar is susceptible to precipitation attenuation. This paper presents an X-band attenuation correction method based on the light gradient machine (LightGBM) algorithm (the XACL method), then compares it with the ZH correction method and the ZH-KDP comprehensive correction method. The XACL method was validated using observations from two radars in July 2021, the X-band dual-polarization weather radar at the Shouxian National Climatology Observatory of China (SNCOC), and the S-band dual-polarization weather radar at Hefei. During the rainfall cases on July 2021, the results of the attenuation correction were used for precipitation estimation and verified with the rainfall data from 1204 automatic ground-based meteorological network stations in Anhui Province, China. We found that the XACL method produced a significant correction effect and reduced the anomalous correction phenomenon of the comparison methods. The results show that the average error in precipitation estimation by the XACL method was reduced by 39.88% over 1204 meteorological stations, which is better than the effect of the other two correction methods. Thus, the XACL method proved good local adaptability and provided a new X-band attenuation correction scheme. [ABSTRACT FROM AUTHOR]

• A soil-tunnel periodic model with a track slab was proposed based on wave transform. • Train load and its component were mathematically decomposed in the generalised modal space. • Two measures to improve calculation efficiency without loss of accuracy were presented. • Accuracy and efficiency were verified by comparing the results with literature and measurements. The prediction of ground-borne vibrations induced by underground trains in tunnels is advantageous for guiding vibration-mitigation designs. The supporting forces of the fastener acting on the track bed that is induced by the train operation are spatially periodic in the tunnel axis direction. Utilising this feature, this paper proposes a novel periodic tunnel-soil model with a track slab to simulate the propagation of train-induced vibrations. The periodic tunnel-soil model based on wave transformations is briefly introduced, and then the slab beam is solved analytically and combined with the tunnel invert using equivalent springs based on the generalised modal function series. The train load and its single component are mathematically decomposed in a generalised modal space for application to the semi-analytical periodic model. Two measures for further improving the calculation efficiency of the semi-analytical model under the moving train load are presented and discussed in detail. The formulation correctness of this model is ensured by literature verification. Furthermore, an in-situ measurement of the vibration on the tunnel wall and ground surface by the train passage in the Hefei metro is conducted to validate this semi-analytical model. It is demonstrated that the proposed model is accurate and efficient for predicting ground-borne vibrations generated by train loads, thus it has the potential to predict vibration levels at a large number of receiver points around a newly constructed metro line. [ABSTRACT FROM AUTHOR]

To analyze the temporal variation characteristics of PM2.5 concentration and its influencing factors in Hefei, this paper utilizes mixed frequency data of air pollution and socio-economic development from 2013 to 2021, and constructs an adaptive change point detection model and fusion of Lightgbm in Machine Learning Models and LGBNN in multilayer neural networks to examine the change point characteristics and significant factors affecting PM2.5 concentration changes in Hefei. The findings indicate evident periodic oscillation patterns in PM2.5 concentration in Hefei, with a greater number of decreasing variables compared to rising variables in the sequence, and the change points exhibit a distinct "phased" characteristic. Regarding the influencing factors, the feature selection analysis conducted on multiple machine learning models like LGBNN reveals that policy factors exhibit the highest prominence, followed by social economy development, air pollution, and meteorological factors. [ABSTRACT FROM AUTHOR]

Copyright of Railway Signalling & Communication Engineering is the property of Railway Signalling & Communication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As an essential parameter to represent vehicle following characteristics, distance headway (DHW) plays an essential role in microtraffic flow simulation, traffic control, and traffic safety alarm. However, due to the randomness, nonlinearity, and correlation of DHW data, constructing DHW prediction models is difficult. Moreover, few studies have considered the time correlation between the historical DHW and the target DHW. To solve the above problems, a DHW prediction model is proposed in this paper by integrating entropy-based grey relation analysis (EB-GRA) and temporal convolutional network (TCN), named as EB-GRA-TCN model. In the model, the EB-GRA is adopted to calculate the correlation between the target DHW and historical DHW sequences, and the DHW data with high correlation are dynamically selected as the optimal input of the DHW prediction model. Then, the TCN algorithm is used to train the DHW prediction model. The TCN architecture integrates the advantages of recurrent neural network (RNN) and convolutional neural network (CNN), which could fully use the previous DHW information. In the experiment, the DHW data from Hefei Expressway are utilized for training the EB-GRA-TCN model. The prediction results showed that the average root mean square error (RMSE) and mean absolute error (MAE) of the proposed model were 0.115 and 0.090, respectively, in the 5, 10, and 15 predicted steps. Compared with the autoregressive integrated moving average (ARIMA), TCN, RNN, and long short-term memory (LSTM) models, the EB-GRA-TCN model achieved the best prediction accuracy. The results indicated that the EB-GRA-TCN model obtained good predictive performance and could provide support for road traffic control and traffic safety warming. [ABSTRACT FROM AUTHOR]

Cataract is the first cause of blindness and the major cause of visual impairment worldwide. Under conditions of global warming, researchers have begun to give attention to the influence of increasing temperature on cataract patients. Our paper aimed to investigate the association between extreme heat and hospital admissions for cataract in Hefei, China. Based on data from the New Rural Cooperative Medical System and National Meteorological Information Center, we used a generalized additive model and a distributed lag nonlinear model to examine the relationship between extreme heat and hospitalizations for cataract, with consideration of cumulative and lagged effects. When current mean temperature was above 28 °C, each 1 °C rise was associated with a 4% decrease in the number of cataract admissions (RR = 0.96, 95% CI = 0.94–0.98). The cumulative relative risk over 11 days of lag was the lowest, which indicated that every 1 °C increase in mean temperature above 28 °C was associated with a 19% decrease in the number of hospital admissions for cataract (RR = 0.81, 95% CI = 0.75–0.88). In subgroup analyses, the negative association between extreme heat and hospital admissions for cataract was stronger among patients who were not admitted to provincial-level hospitals. In conclusion, this paper found that extreme heat was negatively associated with cataract hospitalizations in Hefei, providing useful information for hospitals and policymakers. [ABSTRACT FROM AUTHOR]

Bioaerosols are usually defined as aerosols arising from biological systems such as bacteria, fungi, and viruses. They play an important role in atmospheric physical and chemical processes including ice nucleation and cloud condensation. As such, their dispersion affects not only public health but also regional climate. Lidar is an effective technique for aerosol detection and pollution monitoring. It is also used to profile the vertical distribution of wind vectors. In this paper, a coherent Doppler wind lidar (CDWL) is deployed for aerosol and wind detection in Hefei, China, from 11 to 20 March in 2020. A wideband integrated bioaerosol sensor (WIBS) is used to monitor variations in local fluorescent bioaerosols. Three aerosol transport events are captured. The WIBS data show that, during these transport events, several types of fluorescent aerosol particles exhibit abnormal increases in their concentration, number fractions to total particles, and number fractions to whole fluorescent aerosols. These increases are attributed to external fluorescent bioaerosols instead of local bioaerosols. Based on the HYbrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) backward trajectory model and the characteristics of external aerosols in WIBS, their possible sources, transport paths, and components are discussed. The results prove the influence of external aerosol transport on local high particulate matter (PM) pollution and fluorescent aerosol particle composition. The combination of WIBS and CDWL expands the aerosol monitoring parameters and provides a potential method for real-time monitoring of fluorescent biological aerosol transport events. In addition, it also helps to understand the relationships between atmospheric phenomena at high altitudes like virga and the variation of surface bioaerosol. It contributes to the further understanding of long-range bioaerosol transport, the roles of bioaerosols in atmospheric processes, and in aerosol–cloud–precipitation interactions. [ABSTRACT FROM AUTHOR]

CRTS III slab track adopts unit block structure, which has become the main track structure of 300km/h and above high-speed railway in China. The geometry of ballastless track is the key to ensure the comfort of train operation. In order to realize the geometric shape and position control of CRTS III slab track in the whole process and provide high-speed, stable and comfortable operation conditions for trains, this paper studies the design, manufacture and construction of the track. In the design phase, the layout software is used to realize the intelligent generation of vertical and plane layout scheme. In the manufacturing stage, the supporting mold, tooling and software are developed according to the production process of the track slab to implement automatic measurement and control, and manufacturing accuracy of the track slab platform is ensured by means of information technology. In the construction stage, construction control software is used to dynamically modify the geometric shape and position of the track slab and fulfill layered control of the ballastless track bed, which can effectively improve the smoothness of the high-speed railway line. This technology has been used in Nanchang - Ganzhou High-speed Railway, Shangqiu-Hefei-Hangzhou High-speed Railway, Hefei - Anqing High-speed Railway successively, and played a decisive role in ballastless track bed structure control, fine adjustment and smoothness index control, etc. [ABSTRACT FROM AUTHOR]

The concept of the "no-waste city" has focused increasing attention on the recycling of solid waste. One such waste is reclaimed asphalt pavement (RAP), which is generated during road maintenance. The potential to reuse this resource has attracted extensive attention in recent years. This paper explores this concept via a case study of the reconstruction of two sections of the Beijing-Taipei Expressway (from Bengbu to Hefei, sections K69–K69 + 500 and K69 + 500–K69 + 900). The upper base layer of one section was paved with a novel mixture of emulsified asphalt, mixed with a high proportion of RAP made using plant-mixed cold recycling technology (EAPM-HPRAP). For comparison, the upper base layer of the other section was paved with a conventional large-stone porous asphalt mix (LSPM). The proportions of the components of EAPM-HPRAP were optimized via laboratory-based proportioning design followed by proportioning verification. The results showed that the high-temperature stability, water damage resistance and pavement strength of the EAPM-HPRAP met the specifications of relevant engineering standards. Next, the economic and environmental benefits of this novel approach were estimated. The approach was estimated to save CNY (China Yuan) 1.5–1.8 million in engineering costs per km of road (roadbed width = 27.5 m) and CNY 158–189 million for the whole project (105 km in length). It was also estimated to reduce energy consumption equivalent to 67.41 tons of standard coal per km. Further calculations showed that every km of pavement could reduce CO2 emissions by 176.6 tons, SO2 emissions by 0.6 tons, NOX emissions by 0.5 tons, ash emissions by 17.6 tons and soot emissions by 1.0 tons compared with conventional methods. For the whole road section, this is equivalent to reducing CO2 emissions by 18,543 tons, SO2 emissions by 60.2 tons, NOX emissions by 52.5 tons, ash emissions by 1848 tons, and soot emissions by nearly 105 tons. In summary, it is feasible for EAPM-HPRAP to be used as the upper base layer in highway renovation projects. It reduces the need to mine new ores and allocate land to RAP storage, which is associated with soil and water pollution due to chemical leaching from aged asphalt. This approach provides great economic and environmental benefits compared with the use of conventional pavement technology. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is to investigate the impact of e-government usage on citizen engagement during the COVID-19 crisis in China, in relation to the mediating role of how citizens perceive the government. A model was also proposed to explain the relationship between e-government usage during the COVID-19 crisis and the mediating role that different perceptions of government play in influencing citizens level of engagement. Design/methodology/approach: The research model was tested empirically through a survey conducted online with 866 research participants, comprising of Chinese citizens from three large cities, which include Hefei, Shanghai and Nanjing. Findings: The results in structural equation modeling showed that e-government usage has a significant positive influence on citizens' perception about trust in government, government transparency and government reputation but not significant influence on citizens' engagements. However, an indirect relationship was found out in the mediation analysis. There was also a significant relationship between the different perceptions of government. Mediation analysis showed that all the different perceptions of government mediate the relationship between e-government usage and citizens' engagements during the COVID-19 crisis. The single mediation pathways were found to be most effective mediators, identifying citizens' perception about trust in government to be the most effective mediator. Originality/value: This study filled the gap in literature by examining how e-government usage by Chinese citizens during the COVID-19 crisis helped influence their attitude and behavior. Specifically, this study is one of the first to integrate citizens' usage of e-government and citizens' engagement through the different citizens' perceptions of government such as trust in government, transparency of government and government reputation in a non-liberal country. [ABSTRACT FROM AUTHOR]

In urban traffic systems, alleviating traffic congestion originated from left-turn/U-turn lanes at highly demanded intersections plays an important role in enhancing the traffic efficiency. For a typical intersection, the layout with double left-turn (DLT) lanes is a relatively common geometric feature. However, the effect of DLT scheme on the performance of the entire traffic system is not clear. This paper compares the performance of urban traffic system with different lane function schemes with extended cellular automaton (CA) model considering the car-following, lane-changing, intersection-traversing and route-choice behavior of vehicles. Using the flow-density relation, three macroscopic parameters (average trip completion rate, average traffic flow and average velocity) are examined to evaluate the system performance. With the wide application of DLT scheme, the vehicles can be distributed more evenly among the lanes. As a result, the traffic flow and the trip completion rate will be higher, especially at high density. Case studies of realistic Hefei city network and Sioux Falls networks are also carried out. The results show that the performance of traffic network will be better if more intersections adopt the DLT scheme. [ABSTRACT FROM AUTHOR]

The extraction and timely updating of land use /cover information is a key issue in remote sensing change detection. The change vector analysis (CVA) is a better method of change detection. However, the CVA method is the blindness of artificial choice of threshold. Moreover, the direction cosine of CVA cannot represent the unique point in change vector space and it can't distinguish the change category effectively. In order to avoid this defect, the midline vector is added to CVA method. In this paper, we use the midline change vector analysis (MCVA) method to detect the land use /cover change in multi temporal remote sensing images. We proposed the two-step threshold method to get the optimal threshold and determine the change and the unchanged region of the difference remote sensing image. We chose Hefei city of Anhui Province as the study area, and adopted two Landsat5 TM images in 2000 and 2008 year as experiment data. We use the MCVA and two-step threshold method to achieve remote sensing change detection. In order to compare the detection accuracy between MCVA method and the traditional post classification comparison method, the paper choose the same area (178 pixels × 180 pixels) in the two images to analyse the accuracy, and compare the accuracy of MCVA method with that of the traditional post classification comparison method based on SVM. The experiment results show that the MCVA method has higher overall accuracy, lower allocation disagreement and quantity disagreement. What's more, the overall accuracy of MCVA method can reach nearly 60%, much higher than the traditional post classification comparison method (less than 40%). And the MCVA method can effectively avoid the problem of change vector direction cosine values are not unique, and the result is much better than the traditional post classification (SVM) comparison method. It indicates that MCVA is a more effective method in land use / cover change detection for middle resolution multispectral images. [ABSTRACT FROM AUTHOR]

In order to investigate the equivalent complex refractive index of atmospheric aerosols near the Earth's surface, we conducted measurements in the Hefei region from March to April 2022. These measurements utilized a micro-pulse lidar, an Aethalometer, and a Portable Optical Particle Profiler. These measurements encompassed aerosol particle size distribution as well as standard meteorological parameters including temperature, humidity, atmospheric pressure, and wind speed. Subsequently, this dataset was employed to develop an optimization algorithm for retrieving the equivalent complex refractive indices of near-surface aerosols. The methodology relies on lookup tables containing data for extinction efficiency and absorption efficiency factors. It operates on the premise of aerosol property stability within a defined time frame, utilizing measured extinction and absorption coefficients as simultaneous constraints during this period to inversely derive both the real and imaginary parts of the aerosol complex refractive index. Results from the simulation analysis reveal that the newly optimized retrieval algorithm, which relies on lookup tables, exhibits reduced sensitivity to instrument errors when compared to single-point constraint algorithms. This enhancement results in a more efficient and dependable approach for retrieving the aerosol complex refractive index. Empirical inversion and simulation studies were carried out to determine the aerosol equivalent complex refractive index in the Hefei region, utilizing measured data. This inversion process yielded an average complex refractive index of 1.48-i0.017 for aerosols in the Hefei region throughout the experimental period. Correlation analysis unveiled a positive association between the real part of the aerosol complex refractive index and the single-scattering albedo (SSA), whereas the imaginary part displayed a linear negative correlation with the SSA. The mathematical relationship between the real part and the SSA is y = 0.19 x + 0.62 , and the corresponding relationship between the imaginary part and the SSA is y = − 5.3 x + 0.99 . This research offers a novel method for the retrieval of the aerosol equivalent complex refractive index. [ABSTRACT FROM AUTHOR]

Taking the domestic waste reverse logistics network in Hefei as the research object, considering the multi frequency recycling and vehicle sharing scheduling strategy, a reverse logistics network optimization scheme based on the operation cost of the reverse logistics network is proposed. Firstly, a reverse logistics recycling operation cost model is constructed, which includes the construction cost of reverse logistics infrastructure, equipment maintenance cost, the sum of the transportation cost of municipal solid waste and the treatment cost of non-recyclable waste at all levels, and a product maximization revenue model of the recycling center is established. Secondly, according to the characteristics of the model, a k-means spatio-temporal clustering algorithm considering the geographical location of waste transfer stations, recycling frequency and recycling time window is designed, and then an improved GA-PSO hybrid algorithm is proposed. The effectiveness of the model and algorithm is verified by comparing with HGA, GA-TS and HACO algorithms. Finally, according to the actual data of Hefei domestic waste reverse logistics network, the optimization research was carried out, and the recycling frequency and vehicle scheduling of transfer stations in different locations were analyzed. The results show that the model and algorithm proposed in this paper can carry out the optimal selection of recycling cost, resource sharing of recycling vehicles and reasonable vehicle routing optimization scheduling, and the operation cost of reverse logistics network is reduced by 8% compared with the previous one; As the transportation distance is reduced, the transportation cost is greatly reduced, and the treatment efficiency of municipal solid waste is improved. [ABSTRACT FROM AUTHOR]

Ma'anshan City, located in the Yangtze River Delta region, is a demonstration city for handling the industrial transfer of the Nanjing, Hefei, and Wanjiang Metropolitan Areas in China. Developing and utilizing underground space can effectively alleviate the land scarcity issue in urban development. The suitability evaluation of underground space development in Ma'anshan City offers valuable information support for the economic and efficient use of land resources. Drawing on POI, night light radiance, and population data, this study selects six indices, including POI kernel density, road node connection rate, night light radiance in the most recent year, change amplitude of night light radiance over the years, population density in the most recent year, and change amplitude of population density over the years. The study conducts a comparative analysis of the suitability of underground space development in Ma'anshan City using the Analytic Hierarchy Process (AHP) and the Combination Weight Method. Comparing the results of AHP and Combination Weight Method reveals that the latter can identify a more extensive range of highly suitable development zones than the former. This study provides an effective method for evaluating the suitability of underground space development in urban planning, which contributes to promoting sustainable urban development. [ABSTRACT FROM AUTHOR]

• Pedestrian spatial violations at unmarked roads were collected by an unmanned aerial vehicle and a camera. • Male pedestrianshave a higher violation lkelihood. Younger pedestrians waited a shorter time before crossing and had fewer observations while crossing. • The illegal crossing probability with companions is higher than that of crossing alone. • Shorter intersections spacing, higher vehicle flow and longer crossing length all reduce the illegal propensity. Pedestrian violations are a major cause of pedestrian accidents. Considering that pedestrians are vulnerable to mortality and severe injury in traffic accidents, it is necessary to conduct a study of the factors influencing the occurrence of unmarked street crossing violations and to improve pedestrian safety in a targeted manner. This paper investigated pedestrian spatial violations on unmarked roadways at six high-traffic locations in Hefei and examined the effects of the road environment, pedestrian crossing behaviour, and pedestrian characteristics on pedestrian spatial violation decisions. Thirty variables with a total of 723 samples were obtained by an unmanned aerial vehicle (UAV) and a camera. The purpose of this study was to gain an understanding of pedestrian spatial crossing violations at unmarked roadways. A random parameter logit model was used to establish a pedestrian crossing decision model for roadway violations. The results indicate that males are more likely to violate than females; the probability of violation with companions is higher than that of crossing alone; when pedestrians cross with other strangers in the same direction, the rate will decrease; and shorter intersection spacing, a higher vehicle flow, and a longer pedestrian crossing length all reduce the illegal crossing propensity. The findings should be indicative to help traffic road construction departments and traffic participants take effective measures to improve road safety. [ABSTRACT FROM AUTHOR]

Copyright of Railway Signalling & Communication Engineering is the property of Railway Signalling & Communication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Spatial Markov chain can effectively explore the spatial evolution trend of housing price under the influence of lag factor. This paper uses spatial autocorrelation and spatial Markov to study 353 second-hand houses in Hefei. The results show that (1) the housing price of Hefei urban area presents a situation of "two points and one side," the high housing price is concentrated in the south and southwest of the urban area, and the price level gradually weakens from south to north, and the housing development shows a north-south differentiation. (2) There is a significant spatial autocorrelation between second-hand housing prices in Hefei. The "high-high" residential price clusters are mainly distributed in Shushan District and Binhu New Area, while the "low-low" residential price clusters are mostly in Yaohai district and its surrounding areas. The number of "low-high" agglomeration and "high-low" agglomeration is small, and the degree of change is not big. (3) Under the influence of different neighborhood environments, the housing prices in urban Area of Hefei show club convergence overall. At the same time, under the short-term influence of the policy, the housing prices of low level and middle and low level are promoted in the same neighborhood environment, while the housing prices of high level and middle and high level are negatively affected. [ABSTRACT FROM AUTHOR]

In the context of disaster normalization, the concept of "resilience" has been gradually introduced into the field of disaster prevention and mitigation in urban communities. In order to resist the increasingly frequent disasters caused by extreme weather, it is necessary to shift the focus of building resilient urban communities to the level of stormwater management. Community resilience is a disaster prevention and mitigation capability based on community resources. In order to solve the deficiency of storm and flood management in the current construction of resilient communities in China, it is necessary to establish a quantitative evaluation system to evaluate it. This paper uses the analytic hierarchy process and Delphi method to establish a community resilience evaluation system from the perspectives of community material space level, community management level and individual level. Then three communities in Hefei City, Anhui Province are selected for practical application of the system, and corresponding optimization and transformation strategies are proposed. The results show that: (1) The resilience of community stormwater management is closely related to the integrated environment of the community, the allocation of flood control facilities and the daily disaster prevention and mitigation management; (2) The ability of disaster prevention and mitigation and the awareness of public participation of the residents in all communities are relatively weak, and the communities invest less in the popularization of stormwater management wisdom; and (3) Resilient communities should not only pay attention to the construction of non-engineering disaster prevention measures, but also to the application of small-scale green infrastructure oriented toward stormwater management. [ABSTRACT FROM AUTHOR]

It is an important content to analyze the uncertainty of emission from greenhouse gases in compiling the emission inventory. Reliable uncertainty estimates can also be used to increase the quality of emission inventories. This paper took the emission of CH4 from the solid waste landfill in Hefei City in 2014 as an example, and employed the mass balance method to compute its emission. Monte Carlo method was used to carry out the sensitivity analysis and compute uncertainty. Through computing, 95% confidence interval of CH4 emission from landfill in Hefei City was (1.89~3.40) × 104 t. The mean value was 2.61 × 104 t with uncertainty range of –27.59%~30.27%. Among all the parameters, the decomposable proportion of DOC (DOCf) showed the greatest impact on the emission of CH4 from the landfill and its contribution to emission result was 26.33%. Followed by the degradable organic carbon (DOC) was 26.29%, the amount of solid waste (MSW) was 13.63%, methane correction factor (MCF) was 6.93% and the proportion of methane in landfill gas (F) was 6.58%. The results showed that compared with traditional error propagation method, it improved the accuracy and quality of assessment and provided a scientific basis to improve the quality of inventory as well. [ABSTRACT FROM AUTHOR]