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Cable-stayed bridges have been widely used in large-span bridge engineering because of their large span capacity and novel structure. The frequent traffic of vehicles transporting flammable and explosive materials has increased the incidence of bridge fires. After being burned, the cable-stayed bridge will suffer from varying degrees of damage, which affects its performance. Therefore, mechanical analysis and evaluation of the fire-damaged cable-stayed bridge are necessary. Due to the development of technology, the structural analysis of cable-stayed bridges has gradually shifted from experimental methods to numerical simulation or artificial intelligence methods, and from local performance research to holistic research. In this paper, a fire accident in the Sifangtai Bridge in Harbin, China, is taken as a case study. Finite element software and damage theory calculation methods were used, and the static and dynamic performances of the bridge under the condition of cable fire damage were analyzed. The results show that the variation of cable force during the movement of vehicle load along the bridge is relatively small, within the range of 7% to 12%. The fusing of the upper cables of the bridge tower has the greatest impact on the deflection of the beam, while the fusing of lower cables has the same impact on the deflection of the entire bridge as the undamaged state. Near the fused cables, cable forces change significantly, increasing by over 20%. As the degree of damage increases, the increase in deflection of the beam becomes more pronounced. The impact of different degrees of cable damage on the dynamic performance of cable-stayed bridges is reflected in quantitative changes. As the degree of cable damage and the amount of fusing increase, the change in structural frequency becomes more pronounced. This paper not only provides technical support and a theoretical basis for the performance analysis of cable-stayed bridges damaged by fire, but it also improves the research content of combining static and dynamic performance, which provides important reference values for similar research in the future. [ABSTRACT FROM AUTHOR]

The connotation and measurement standard of "fairness" in parkland planning is closely related to the level of urban development and residents' needs, with solid realism and dynamics, and it is still a complex problem to control accurately in planning. Therefore, to conduct a more comprehensive study, taking the main urban area of Harbin as an example, this paper combined urban development background and practical problems at different stages and, based on POI and AOI data, divided the connotation of "equity" in park green space planning into two levels: "spatial equity" and "social equity". Based on these two levels of fairness, the research framework of urban park green space layout is constructed. Kernel density estimation and GIS-based network analysis were used to study the spatial layout and accessibility of urban parkland. The ability to match supply and demand for parkland in the study area as a whole was analyzed using a gridded two-step moving search method, as well as the degree of equity in the enjoyment of urban parkland by vulnerable groups including the elderly and children using the Lorenz curve with the Gini coefficient, the share index, and the entropy of the locality. The results show that: (1) the parkland is concentrated in the seven main urban areas of the two–two junctions, and the cohesion distribution trend is outside the distribution. (2) Motorized vehicles have the best 15-min accessibility for travel, but it still does not cover all the parkland. (3) Supply and demand within the region are unsatisfactory, with the area with the strongest supply and demand capacity for parkland accounting for only 3.19% of the total area. (4) The Gini coefficient of parkland enjoyed by the residents of Harbin city center is 0.407, with a massive gap in the overall distribution. In addition, the share index of vulnerable groups of the elderly and children all have share indices below 1, and the results of the analysis of locational entropy indicate that the level of street park green space resources enjoyed by these two groups belongs to the low socio-spatial equity pattern, which is not balanced. This study investigates the spatial layout of urban parkland from two equity levels, which can provide new ideas for the equity study of urban green space planning. [ABSTRACT FROM AUTHOR]

Realizing the building of urban resilience and improving urban resilience has become important contents of urban development. In view of this phenomenon, relying on the framework of trio spaces, which includes physical space, societal space, and cyberspace, the evaluation index system of urban resilience is established. The evaluation model of urban resilience is constructed by using CRITIC-entropy weight and the cloud evaluation method. Four sub-provincial cities in Northeast China, Harbin, Changchun, Shenyang, and Dalian, are selected as the analysis objects, and the resilience of each city is comprehensively evaluated and spatially evaluated. From the urban resilience comprehensive evaluation, this paper found the cities with the highest resilience levels in 2014, from 2015 to 2018, and from 2019 to 2020 are Dalian, Changchun, and Shenyang, respectively. The city with the lowest resilience level is Harbin. Although there are differences in resilience evaluation values of four cities, the resilience levels of these cities are all "qualified". From the urban resilience sub-space evaluation, this paper explored the shortcomings of the resilience of physical space, societal space, and cyberspace of each city through the comparison. Then, some suggestions about highlighting the enhancement of cyberspace resilience, emphasizing resilience-building balance, conducting resilience evaluation, and monitoring regularly, and local government policy support are proposed to help to promote urban resilience from the concept of trio spaces. [ABSTRACT FROM AUTHOR]

Surface water is a vital resource for human survival. However, economic and social development has resulted in significant pollutants from human activities, causing environmental pollution in watersheds. This pollution has had a profound impact on the surface water environment. However, limited studies have been conducted on the environmental risk evaluation of the watershed. In this study, we accounted for agricultural, industrial, and domestic source discharges in the districts and counties of the Harbin section of the Songhua River Basin for 2021. Data were collected from Statistical Yearbooks and governmental departments, and the characteristics of pollutant discharges in Harbin's districts and counties were analyzed. Subsequently, we employed the Back Propagation neural network optimization method, combining remote sensing data, accounting data, pollution discharge data from each district and county, and economic and social data from the Statistical Yearbook and literature. This fusion of multiple data sources facilitated the construction of a watershed environmental risk evaluation system. The analysis considered four levels: economic and social, resource load, environmental infrastructure, and pollution discharge. Via this comprehensive evaluation, we identified the reasons for environmental risks in the water environment of the Harbin section of the Songhua River Basin. The evaluation results indicate that Nangang District, Xiangfang District, and Pingfang District face a higher risk to the water environment. Consequently, recommendations for mitigating water environment risks in these areas and across Harbin City are presented. The research methods and findings in this paper contribute valuable insights for developing control strategies to manage water quality in critically polluted areas of the Harbin section of the Songhua River Basin, providing a scientific foundation for regional river water quality management studies. [ABSTRACT FROM AUTHOR]

Situated at middle-to-high latitudes with limited thermal resources, Northeast China is the primary maize-producing region in China. It is also one of the regions most significantly impacted by climate change. Given the persistent impact of climate change, it is crucial to elucidate the effects of the varying thermal conditions and low temperatures for different sowing dates on the growth, development, and grain maturity of spring maize. To ensure secure maize production and disaster prevention, choosing the optimal sowing time for spring maize holds significant implications for the judicious utilization of climatic resources, risk mitigation, and the provision of meteorological guidance. Moreover, it can serve as a technical reference for relevant departments to conduct climate evaluation, disaster monitoring, prediction, and assessment, as well as impact analysis of corn production safety. Additionally, it can provide meteorological evidence to ensure food security and promote the sustainable development of modern agriculture. An interval sowing experiment of spring maize was conducted in Harbin in the north of Northeast China. Two varieties were used in the experiment. Four sowing dates were set, and the interval between adjacent sowing dates was 10 days. The local perennial sowing time, 5 May, was set as the second sowing date, with one date set later and two dates set earlier. During the experiment, the growth process, grain dry matter, seed moisture content, yield components, and temperature of spring maize were observed. The impact of temperature conditions on maize growth and yield formation was analyzed in this paper through mathematical statistics, which further led to the establishment of a monitoring and evaluation model for assessing the effect of thermal conditions and temperature on maize. The results showed that the growth rate of spring maize was closely related to temperature. When the average temperature, minimum temperature, and maximum temperature increased by 1 °C, the average emergence rate increased by 1.05%, 0.99%, and 1.07%, respectively, and the average vegetative growth rate increased by 0.16%, 0.16%, and 0.09%, respectively. The change rate of ≥10 °C active accumulated temperature was significantly correlated with the change rate of the dry weight of the grain kernel, which conformed to the quadratic equation of one variable. The temperature influence coefficients of different sowing dates varied from 1.0% to 1.7%. The relationship between the accumulated values of 10 ℃ active accumulated temperature and the grain moisture content of spring maize was a logarithmic function. From 10 to 50 days after anthesis, the effect of temperature can explain about 95% of the change in grain moisture content. After physiological maturity, the effect of thermal conditions can only explain 56–83%. The temperature influence coefficient ranges from 1.3% to 13.8%. Comparatively speaking, the second sowing date is the most suitable sowing date. Early sowing is prone to encounter low temperatures, resulting in underutilization of the early heat, while late sowing is prone to less heat. Both conditions are not conducive to better improve the yield of spring maize. [ABSTRACT FROM AUTHOR]

In the knowledge economy, innovation is playing an increasingly important role in urban sustainable development. Thus, how to strengthen the construction of innovation spaces has become a significant issue. Based on data from high-tech enterprises in the central urban area of Harbin, this study analyzes the distribution, agglomeration characteristics, and influencing factors of urban innovation spaces. The influencing factor index system was constructed based on four aspects: innovation support, service facilities, the social environment, and the natural environment. After analyzing these influencing factors through comparing the results obtained with an ordinary least squares (OLS) model and a geographical weighted regression (GWR) model, the GWR model was determined to have a better fitting effect and was thus used for further analysis. The findings are as follows: (1) Five closely related clusters of innovation spaces are identified. Innovation space has a significant agglomerating distribution pattern. (2) Overall, factors supporting innovation and transportation station factors have a positive effect on the agglomeration of innovation spaces, while natural environment factors have a negative effect on small innovation areas. (3) By region, the aggregation of innovation spaces in downtown areas is slightly negatively affected by service facilities, whereas those in the Harbin New District are mainly supported by policies and those in the Pingfang District are positively affected by the quantity of the labor force. Finally, based on the research results, some suggestions are put forward to promote the development of urban innovation spaces. This paper has certain guiding significance for optimizing and improving the construction and development of urban innovation spaces. [ABSTRACT FROM AUTHOR]

Forest floor dead fuel moisture content (DFMC) is an important factor in the occurrence of forest fires, and predicting DFMC is important for accurate fire risk forecasting. Large areas of forest surface DFMC are difficult to predict via manual methods. In this paper, we propose an unmanned aerial vehicle (UAV)-based forest surface DFMC prediction method, in which a UAV is equipped with a multispectral camera to collect multispectral images of dead combustible material on the forest surface over a large area, combined with a deep-learning algorithm to achieve the large-scale prediction of DFMC on the forest surface. From 9 March to 23 March 2023, 5945 multispectral images and 480 sets of dead combustible samples were collected from an urban forestry demonstration site in Harbin, China, using an M300 RTK UAV with an MS600Pro multispectral camera. The multispectral images were segmented by a K-means clustering algorithm to obtain multispectral images containing only dead combustibles on the ground surface. The segmented multispectral images were then trained with the actual moisture content measured by the weighing method through the ConvNeXt deep-learning model, with 3985 images as the training set, 504 images as the validation set, and 498 images as the test set. The results showed that the MAE and RMSE of the test set are 1.54% and 5.45%, respectively, and the accuracy is 92.26% with high precision, achieving the accurate prediction of DFMC over a large range. The proposed new method for predicting DFMC via UAV multispectral cameras is expected to solve the real-time large-range accurate prediction of the moisture content of dead combustible material on the forest surface during the spring fire-prevention period in northeast China, thus providing technical support for improving the accuracy of forest fire risk-level forecasting and forest fire spread trend prediction. [ABSTRACT FROM AUTHOR]

The unique climate and the landscape of severely cold regions in winter attract many tourists. The outdoor thermal environment affects the space use and the tourist experience, becoming one of the key factors in the design of tourist attractions. The outdoor thermal comfort of tourists from different regions should be considered, but it has been poorly studied in winter in severely cold regions. This paper explores the differences in outdoor thermal comfort in winter between local and non-local tourists through the field measurement of the thermal environment and a questionnaire survey of thermal comfort at tourist attractions in Harbin, China. The results show that the proportion of local tourists who expect the air temperature and solar radiation to rise in winter is higher than that of non-local tourists. The thermal sensation vote of local tourists is generally higher than that of non-local tourists. When the Physiologically Equivalent Temperature (PET) < −6 °C, the thermal satisfaction of non-local tourists is higher than that of local tourists. When the PET value is −10 °C, the thermal comfort of non-local tourists is the highest. The thermal comfort decreases with the rise or fall of the PET value. When −28 °C < PET < −7 °C, the thermal comfort of non-local tourists is generally higher than that of local tourists. This paper provides a reference and evaluation basis for urban tourist attractions' outdoor thermal environment design in severely cold regions. [ABSTRACT FROM AUTHOR]

Harbin, as a popular tourist city in China, and the host of the 2025 Asian Winter Games, boasts rich tourism resources and significant potential for further development. The structure of the urban road network is a crucial factor influencing the spatial distribution of tourism service facilities. However, the current research on the correlation between the two, analyzed at multiple scales based on tourists' travel preferences, is not sufficient. First, utilizing the questionnaire survey method to analyze tourists' travel preferences and combining it with the theory of 15-min life circle, we determine the study scales at 500 m, 1000 m, 3000 m, and 5000 m. Secondly, the integration value and choice value of roads in the main urban area of Harbin are analyzed based on the theory of spatial syntax. The spatial distribution characteristics of tourism service facilities are then revealed through kernel density analysis. Finally, the correlation between the road network structure and the distribution of various types of tourism service facilities in Harbin at different scales is determined through buffer analysis and Pearson bivariate correlation analysis. The results show that: (1) Integration value plays a significant positive role in promoting the clustering of tourism service facilities, especially tending to cluster in areas with high integration value formed at a scale of 500 m; (2) At the scale of 3000 m, the distribution of tourism service facilities exhibits a significant correlation with the choice value; (3) The correlation between dining, shopping, and entertainment facilities and the integration value decreases with the increase in scale, whereas the spatial distribution of accommodation and attraction facilities does not exhibit a regular pattern with changes in integration value. In addition, this paper also puts forward targeted suggestions for optimizing the urban road network structure, reasonably locating tourism service facilities, and implementing balanced regional development. The contribution of this study is that it will help improve tourists' travel experience in the city and provide scientific support for promoting the overall sustainable development of tourism in Harbin. [ABSTRACT FROM AUTHOR]

The walkability of the built environment has been shown to be critical to the health of residents, and open data have been widely used to assess walkability. However, previous research has focused on the relationship between the built environment and walking behavior rather than perceived walkability, and there is a lack of systematic research on walkability at the urban scale using open data. This paper presents a methodological framework for systematically measuring and assessing perceived walkability at the urban scale, considering general and specific features. The walkability indices are obtained using variables from open data or calculated automatically through machine learning and algorithms to ensure they can be evaluated at a larger urban scale. The proposed method is applied to Harbin, China, to assess the perceived walkability of streets using hundreds of thousands of street view images and points of interest obtained from open data. The results are compared with a subjective evaluation of walkability to validate the proposed method. The results demonstrate that measures of the urban built environment can describe perceived walkability. Thus, the proposed framework shows promise for assessing the walkability of urban spaces, supporting policy proposals, and establishing design guidelines for optimising urban spaces. [ABSTRACT FROM AUTHOR]

Urban high-temperature disasters have gradually emerged as a significant threat to human society. Therefore, it is crucial to assess and identify areas at risk of such disasters and implement urban planning measures aimed at mitigating their impact. Additionally, a multitude of studies have demonstrated the significant cooling effect of urban blue-green spaces (UGBS), which play a pivotal role in urban environments. Incorporating a UBGS layout into planning and evaluation processes has substantial potential for mitigating high-temperature disasters. This paper presents the construction of a set of assessment processes for mitigating urban high-temperature disaster risk using a UBGS structure layout specifically for the main urban area of Harbin, China. We employed GIS and multi-source remote sensing imagery to develop local climate zone (LCZ) maps applicable to the designated study area. The differentiated impact of UBGS factors on high-temperature disaster risk was determined using the multi-scale geographical weighted regression model (MGWR). The results showed the following: (a) There was an overall low risk level, with 19.61% of the high-risk areas concentrated within the second ring road, forming a spatial pattern characterized by "one line, one cluster". (b) The risk of the building category LCZs was generally higher than that of the natural category LCZs. The risk of the architectural LCZs could be summarized as the risk of low-density LCZs being smaller than that of the high-density LCZs, except LCZ 5. The mean value of the LCZ 2 and LCZ 5 types was the highest. (c) Through indicator screening, AREA_MN, SHAPE_MN, PD, and NP were found to be significant determinants influencing the risk, and the effectiveness and spatial differentiation of these main factors exhibited notable disparities. (d) By comparing different LCZ types, we concluded that the mitigation effect of these factors on risk may be interfered with by building height (BH); NP may be positively interfered with by BH; and PD and SHAPE_MN may be negatively interfered with by BH. The research results provided a new perspective and practical scientific basis for high-temperature disaster risk-mitigation planning based on UBGSs under LCZ classification. [ABSTRACT FROM AUTHOR]

Simple Summary: This study explored how urbanization (urban heat island effect and air pollution) affects urban tree growth. The radial growth and xylem anatomical characteristics of trees in urban and rural areas of Harbin were compared by means of tree-ring anatomy. Results showed that there were significant differences in the growth of both broadleaf trees and conifers between urban and rural areas. Urbanization may have the effect of slowing down tree growth, and conifers may be more sensitive to urbanization. Warming and drying climate in Harbin may be an important factor affecting tree growth. Our findings provide a theoretical basis for the future evaluation of the effect of urbanization on tree growth and ecological benefits, as well as the selection of tree species in urban forests. In the context of the intensification of global urbanization, how urbanization (urban heat island effect and air pollution) affects urban tree growth is not fully understood. In this paper, the radial growth and xylem anatomical characteristics of three different tree species (Quercus mongolica, Fraxinus mandshurica, and Pinus sylvestris var. mongolica) in urban and rural areas of Harbin were compared by means of tree-ring anatomy. The results showed that there were significant differences in the growth of both broadleaf trees and conifers between urban and rural areas. The vessel number, cumulative area of vessels, and theoretical hydraulic conductivity of all tree species in rural areas were higher than those in urban areas, indicating that urbanization may have the effect of slowing down growth. However, broadleaf trees in urban areas had higher vessel density and a greater percentage of a conductive area within xylem and theoretical xylem-specific hydraulic conductivity. The thickness of cell walls and cell wall reinforcement index of P. sylvestris var. mongolica were strongly reduced by air pollution, implying that it may be more sensitive to urbanization. Compared to Q. mongolica, F. mandshurica showed less sensitivity to urbanization. Warming and drying climate in Harbin may be an important factor affecting tree growth. [ABSTRACT FROM AUTHOR]

To study the heating performance of a solar-assisted cold-water phase-change-energy heat pump system, its heating performance under series and parallel connections is simulated for a community in Harbin, the influence of ice thickness on the different operation modes is analyzed, and the economy of the system is calculated for series and parallel connections in this paper. The results show that the water supply temperature is higher and more uniform in the parallel operation, and more terminal heat is supplied; the ice thickness has more of an influence on the series connection compared to the parallel connection; and the dynamic payback period is 6.72 years for the series connection and 7.28 years for the parallel connection. This case study can serve as a guide for practical engineering application projects and act as a reference for heating and economic data for the promotion of this heat pump system. [ABSTRACT FROM AUTHOR]

The sustainable use of water resources has become increasingly crucial given the present water supply and demand situation. In this study, the degree of sustainable water resource utilization in Harbin City from 2014 to 2021 was calculated using a fuzzy identification model with a combination of the "sequential relationship analysis method (G1) and coefficient of variation method (CVM)" and 18 evaluation indicators retrieved for water resources, reflecting social, economic, and ecological aspects. The study shows that (1) in terms of the research method, the combined weighting of "G1-CVM" is a feasible approach to avoid the shortcomings of single weighting and (2) in terms of the evaluation of water resources sustainable utilization, the spatial distribution of water resources in each district (county) of Harbin City has been stable over the past 8 years. The spatial distribution pattern is relatively stable, with the three regions of Binxian, Bayan, and Shuangcheng showing better sustainable water resource utilization and the three regions of Tonghe County, including the main urban area and Wuchang City, showing deteriorating sustainable water resource utilization. As a whole, the spatial distribution of sustainable water resources in the 13 districts (counties) of Harbin City from 2014 to 2021 shows a negative correlation, with the main urban area, Wuchang City, Hulan District, Bayan County, Shuangcheng District, and Yilan County showing a clustering type in the local spatial autocorrelation analysis. Based on the evaluation results, the spatial and temporal distribution characteristics of the sustainable use of water resources in Harbin are identified and found to be conducive to the timely adjustment of water resources allocation and the rational use of water resources in each district (county). Meanwhile, the research ideas and methods used in this paper can be applied to research on the sustainable use of water resources in other regions. [ABSTRACT FROM AUTHOR]

With the rapid development of urbanization and the widening gap between urban and rural areas, how to effectively enhance the balanced development of urban and rural areas as well as promote the integrated development of urban and rural areas have become heated topics. Based on the basic theory of urban–rural integration and spatial balance, this paper establishes a comprehensive evaluation system. Using a coupling coordination model and an obstacle degree model, this paper selects 32 indicators from aspects of economy, society and ecology to measure the development level of urban–rural integration in 34 prefecture-level cities in Northeast China from 2000 to 2019. We also analyze the spatial pattern, evolution type characteristics and obstacle factors of urban–rural relations. The results show that: (1) The growth rate of urban development in Northeast China is higher than that of rural development. Except for rural ecology, all dimensions of urban and rural areas have increased year by year, but there are large spatial differences within the region. (2) The urban–rural integration development level of Northeast China is growing constantly and the types of urban and rural coordination are all rising to a higher level. Areas with high urban–rural coordination levels are concentrated in the Harbin–Changchun urban agglomeration and the central and southern Liaoning urban agglomeration, with obvious agglomeration effects. (3) In the coordinated development of urban and rural areas, the restrictive degree of the rural social subsystem was higher than that of the urban subsystem. The restrictive factors in the coordinated development of urban and rural areas are relatively stable, and include per capita consumption expenditure, per capita public budget expenditure, books in public libraries per thousand people, etc. (4) The functions of rural social elements should be enhanced, and the social urban–rural integrated development mechanism should be established to promote the integrated development of urban and rural society. [ABSTRACT FROM AUTHOR]

Maximizing the carbon reduction in substations with minimum cost investments can be achieved by taking advantage of the potential of substations in terms of the envelope and renewable energy, which is significant in promoting carbon reduction in substations. Therefore, firstly, the relationship between building cost–energy consumption–carbon emissions is explored, and then the global optimal calculation model of substation envelope–renewable energy is established, with the lowest life-cycle carbon emission of the substation as the optimization goal. Finally, the validity of the model is verified based on a case study of a typical 110 kV outdoor substation. The model calculation results show that, without considering the cost constraint, Harbin has the highest maximum carbon reduction of 180,350 kg, which is 25.15% and 13.74% higher than the maximum carbon reduction in Shanghai and Haikou, respectively. Furthermore, based on the comparison of the cost and benefits of each carbon reduction technology, a prioritization of various carbon reduction technologies is given for each climate zone. The model established in this paper can provide the optimal configuration of substation carbon reduction technologies with different incremental cost constraints, and provide a reference for the low-carbon design of substations. [ABSTRACT FROM AUTHOR]

The global express market has expanded significantly in recent years. High-speed rail express freight transportation has been implemented between multiple cities in China, significantly improving transportation efficiency and effectively meeting demand. In this paper, an optimization model for HSR (high-speed railway) express transport plan is constructed using a space-time-state network, and an improved adaptive genetic algorithm is designed to solve the model. Reasonable transport schemes could be arranged for each cargo flow with the objective of maximizing operational revenue. The numerical experiment based on the Harbin–Dalian high-speed railway in China verifies the effectiveness and applicability of the proposed model. The results show that for HSR operators, appropriate transport strategies can be planned in terms of delivery priorities and transportation mode selection to make full use of the remaining capacity of HSR trains and increase operational revenue. [ABSTRACT FROM AUTHOR]

The structural characteristics of an urban road network directly affect the urban road network's overall function and service level. Because the hierarchical division and layout form of an urban road network has self-similarity and scale invariance, the urban traffic network has certain time-space fractal characteristics, and fractal theory has become a powerful tool for evaluating traffic networks. This paper calculates and compares five fractal dimensions (FD) of nine districts in Harbin. Meanwhile, each calculated FD is linearly regressed with the area, population, built-up area, building area, the total number and length of roads, and the number of buildings in the region. The results show that the fractal dimensions of the five types are between 1 and 2. In the same district, the values of the FD perimeter and FD ruler are lower compared to the FD box, FD information, and FD mass, whereas those of the FD box and FD information are higher. Compared to the FD box and FD information, the value of FD mass shows unevenly. Based on the current research results, this study discusses the feasibility of using relevant indicators in the fractal process to evaluate the layout of the urban road network and guide its optimization and adjustment. [ABSTRACT FROM AUTHOR]

To scientifically measure the water environment carrying capacity of Harbin City and its change trend, based on analysis of the implications of the sustainability of the urban water environment's carrying capacity, an evaluation index system for the sustainability of the water environment carrying capacity of Harbin City was constructed. Most existing evaluation methods rely on static data to construct correlation functions between research objects and rank criteria, while the dynamic nature of the information is not considered enough. In this paper, we use hierarchical analysis (analytic hierarchy process, AHP) to determine the weights of each index of the system and then apply the projection tracing method (projection pursuit, PP) to optimize the determined weights. Combining the set pair analysis posture evaluation method and bias coefficients method to explore the dynamic balance mechanism between different index factor levels, a sustainability evaluation model for water environment carrying capacity integrating informational evolution is constructed. Finally, the applicability of the optimization model is tested by comparing the confidence criterion judging method. The model realizes quantitative evaluation of the carrying capacity of the urban water environment. It provides a new and effective means for accurate and reasonable determination of the coefficient of variance and the number of links and dynamic analysis of the water environment carrying capacity system and judgment of its sustainable development trend. The results show that the weight for water resource quality is 0.55, which is the subsystem with the greatest overall impact on the carrying capacity of the water environment in Harbin. The evaluation level of the set-to-potential eigenvalue for 2010–2017 is biased positive 2, and the rest of the years are quasi 2. The reduced value of the coefficient of oppositeness corresponding to the years 2010–2017 is more significant. The maximum value of the dynamic evolution of the load-carrying capacity level is nearly −0.35. From the vertical comparison of different levels, it is found that the water environment carrying capacity of Harbin City gradually recovered to the normal loadable level over time. This overall shows an improving trend. [ABSTRACT FROM AUTHOR]

Sound is a memory carrier in places with rich history and culture, which can invoke place memories and images. The purpose of this paper is to explore the effect of soundscape on place attachment in different types of historical blocks. Six historical blocks in Harbin, China, were selected, and a questionnaire survey was conducted to evaluate place attachment and soundscape. The soundscape evaluations of harmony, quietness and nature were significantly higher in residential historical blocks than in tourism historical blocks. The mechanical sound source preference of residential historical blocks was lower than that of tourism historical blocks. The main components of place attachment were place bonding and identity, and place dependence, but in different orders in different types of historical blocks. In tourism historical blocks, the preference of sound source helps to enhance place attachment, especially the sounds of activities and equipment related to the history and culture of the blocks. Soundscapes promote place attachment in tourism historical blocks and are positively correlated with place satisfaction. There was no significant correlation between soundscape and place attachment in the residential historical blocks surveyed. [ABSTRACT FROM AUTHOR]

Ecological security pattern (ESP) can bridge the paradox between ecological conservation and socioeconomic development. Although various methods have been applied to establish ESP successfully, improving its scientificity and reliability for regional sustainability are still great challenges. Taking Harbin administrative region as the study area, this paper integrated the merits of the function-oriented method (assessing the importance of ecological services using the InVEST model) and the structure-oriented method (extracting the connectivity of landscapes based on the MSPA model) to improve the identification of ecological sources more scientifically. Night light data were used to modify the natural resistance surface to reveal the real natural and human disturbance for ES loss during species migration and ecological flows. Then, the ESP was established by combining the ecological nodes after extracting and grading the ecological corridors. The results showed that the individual ES performed with a high spatial heterogeneity and was highly correlated with land use patterns. The extremely important and slightly important were the dominant level types in the study area, and the proportion of extremely important declined greatly from 44.78% in 1980 to 30.14% in 2020. Core was the main landscape type with a proportion of 57.13% and mainly distributed in the Lesser Khingan Mountains and Zhangguangcai Mountains. More than 700 ecological corridors were extracted according to the MCR model and the important ecological corridors were selected based on the gravity model, with 86 ecological nodes obtained from the intersection points of ecological corridors. An ESP of "two zones, two barriers, one axis and one belt" was proposed, and relevant protection measures were put out for the sustainable development in the study area. The findings indicated that imposing ESP could form a stable secure frame for social economic development and ecological protection, avoiding irrational land use modes and excessive dispersion of landscapes. This study could provide valuable references for land use planning and the formulation of related ecological protection policies and regional sustainable development strategies. [ABSTRACT FROM AUTHOR]

As the urban underground space environment gets more complex, the cases of shield machines encountering and cutting through piles are becoming more common. The interaction between the cutter head and pile foundation directly affects the tunneling performance of the shield machine and the safety of the existing structure. To study the interaction between the pile and the shield machine, a calculation model of the interaction force is established. A field test of cutting two piles was conducted and the rationality of the model is verified by comparing the calculation results with field test data. The model is applied in the project of a shield machine cutting bridge piles in Harbin Metro Line 3, China. The shield operation parameters are predicted and compared with field test results. Besides, the impacts of cutting surface width and eccentric distance on interaction force are discussed. The study shows that there is a significant interaction between the cutter head and the piles when the shield machine cuts reinforced concrete piles, which causes obvious changes in the shield operation parameters and shield performance. The number of tools that are inside the cutting area has a significant effect on the additional torque. The additional torque fluctuates with the rotation of cutter head and increases with the increase of the number of tools. The number of these tools is determined by factors such as the layout of tools in the cutter head, cutting surface width and eccentric distance, which influence the position of each tool relative to the cutting area. As the cutting distance increase, the additional torque of the cutter head shows a trend of first increasing and then decreasing and reaches the maximum value when the cutting distance reaches the radius of the pile. Besides, the additional force and additional moment of the cutter head increase with the increase of the cutting surface width. The impacts of eccentric distance on additional force and additional moment are complicated. The results in this paper can provide reference for similar engineering. [ABSTRACT FROM AUTHOR]

Campus lockdown during COVID-19 and the post-pandemic era has had a huge negative effect on college students. As a vital part of interior teaching spaces, colour deeply influences college students' mental health and can be used for healing. Nevertheless, research on this topic has been limited. Based on colour psychology and colour therapy, this paper discusses the relationship between interior teaching space colours (hue and brightness) and emotions among college students. The HAD scale and questionnaire survey method were used. It was concluded that: (1) Anxiety and depression were prominent among the college student population during the quarantine of the university due to the epidemic. (2) Warm colours have an advantage over both cold and neutral colours in creating pleasure, relaxation, and mental attention, with the second in line being the cold and the last being the neutral. Warm colours make it pleasant for individuals while cold colours boost attention. (3) When subjects have higher values of anxiety and depression, they are less satisfied with the colour of the teaching space. (4) In most cases, there is no significant difference in the colour preference of teaching spaces across the gender, grade, and major groups, with females having a higher preference for warm high-brightness classrooms than males. These findings provide crucial ideas for future interior teaching space design and enrich the theories in colour psychology. [ABSTRACT FROM AUTHOR]

In this paper, a solar-assisted enhanced vapor injection air-source heat pump (SC-EVIHP) system was built to investigate its heating performance in cold regions. A typical-weather day in Harbin was selected for the experiment, and the heating characteristics of the SC-EVIHP system were explored under variable working conditions. The experimental results showed that the system was greatly affected by solar radiation intensity. On typical-weather days in winter, the maximum values for the heating capacity and COP of the system appeared at the time of maximum radiation intensity. Compared with conventional enhanced vapor injection air-source heat pump systems (EVI-ASHPs), the heating capacity and COP were increased by 24.9% and 12.5% at most, respectively. The COP of the system increased by at most 11.1% under conditions where the outdoor temperature was −12 °C and the outlet hot air temperature of the solar air collector was 40 °C. The SC-EVIHP system works well in a low-temperature environment and can be widely applied in cold regions. [ABSTRACT FROM AUTHOR]

In this paper, an experimental rig of a prefabricated temporary house (PTH) was first established. Then, predicted models for the thermal environment of the PTH with and without considering long-wave radiation were developed. Next, the exterior-surface, interior-surface and indoor temperatures of the PTH were calculated by using the predicted models. The calculated results were then compared with the experimental results to study the influence of long-wave radiation on the predicted characteristic temperature of the PTH. Finally, the predicted models were used to calculate the cumulative annual hours and the intensity of the greenhouse effect of four different climate cities (Harbin, Beijing, Chengdu, Guangzhou, China). The results showed that: (1) the predicted temperature values of the model considering long-wave radiation were closer to the experimental results; (2) the effect level of the long-wave radiation on the three characteristic temperatures of the PTH from big to small was: exterior-surface temperature, interior-surface temperature, and indoor temperature; (3) the long-wave radiation had the greatest impact on the predicted temperature value of the roof; (4) under different climate conditions, the cumulative annual hours and the intensity of the greenhouse effect considering long-wave radiation were smaller than those without considering long-wave radiation; (5) the duration of the greenhouse effect considering and ignoring long-wave radiation varied significantly with the climate region, and that in Guangzhou was the longest, followed by Beijing and Chengdu, and that in Harbin was the shortest. [ABSTRACT FROM AUTHOR]

Due to the coupling impacts of solar radiation, wind, air temperature and other environmental parameters, the temperature field of steel structures is significantly non-uniform during their construction and service stages. Corrugated web steel beams have gained popularity in structural engineering during the last few decades, while their thermal actions are barely investigated. In this paper, both experimental and numerical investigations were conducted to reveal the non-uniform features and time variation of the corrugated web steel beams under various environmental conditions. The heat-transfer simulation model was established and verified using the experimental temperature data. Both the experiment and simulation results demonstrate that the steel beam has a complicated and non-uniform temperature field. Moreover, 2-year continuous numerical simulations of steel beams' thermal actions regarding eight different cities were carried out to investigate the long-term temperature variations. Finally, based on the long-term simulation results and extreme value analysis (EVA), the representative values of steel beams' daily temperature difference with a 50-year return period were determined. The extreme temperature difference of the steel beam in Harbin reached up to 46.9 °C, while the extreme temperature difference in Haikou was 28.8 °C. The extreme temperature difference is highly associated with the steel beam's location and surrounding climate. Ideally, the outcomes will provide some contributions for the structural design regarding the corrugated web steel beam. [ABSTRACT FROM AUTHOR]

Reasonable building height distribution in urban residential areas is conducive to smoother vertical airflow exchange and promotes sustainable development. This paper studies the influence of building layouts on vertical ventilation in high-rise residential areas in Harbin, China, and discusses typical building layout objectives. The ideal area of 220 × 220 m was determined using statistical analysis and specification requirements, and seven typical layouts were defined based on the distribution of building heights. The computation fluid dynamics (CFD) simulation was verified using wind tunnel testing to improve the accuracy of the Phoenics simulation software. Wind speed, wind pressure, and the Universal Thermal Climate Index (UTCI) in residential areas distributed at different heights were analyzed and evaluated. The results indicated that the Phoenics simulation parameter settings, verified via wind tunnel testing, could achieve reasonable simulation results and different height distribution modes had an impact on the changes in wind speed and wind pressure. The equal-height layout that conformed to the row spacing of the buildings and the layout of taller buildings on the east side could provide higher comfort, and did not require enclosed and downwind layouts. This research can inform the green and livable design of residential buildings and provide a new perspective for the construction of high-rise residential areas in cold cities. [ABSTRACT FROM AUTHOR]

Featured Application: The findings of this study can serve as a valuable reference for the cross-regional integration and optimal utilization of energy resources. Simultaneously, they also contribute to enhancing the accuracy of global solar radiation forecasting by integrating meteorological data and air quality conditions. The majority of the energy required for human survival is derived either directly or indirectly from solar radiation, thus it is important to investigate the periodic fluctuations in global solar radiation over time. In this study, six cities—Harbin, Shenyang, Beijing, Shanghai, Wuhan, and Guangzhou—located in the utilizable areas of solar energy in China, were selected, and the periodicity of the daily global solar radiation of these six cities with time were investigated by means of wavelet power spectrum analysis. Furthermore, Harbin, which has the lowest monthly average of global solar radiation in the cold of winter, was selected to explore the temporal evolution relationship between global solar radiation and other meteorological factors, and air quality factors by wavelet coherence analysis. Among the meteorological factors, the correlation between global solar radiation and sunshine duration exhibits the highest level of consistency. Global solar radiation demonstrates a positive association with atmospheric temperature/wind speed/precipitation over the annual cycle. Conversely, it displays a negative correlation with atmospheric pressure during this time frame. Additionally, on shorter timescales, global solar radiation is negatively correlated with air humidity and precipitation. Among air quality factors, the relationship between global solar radiation and CO/NO2/O3/PM2.5/PM10/SO2 primarily manifests in the broader annual cycle time scale. Within this context, global solar radiation shows a positive correlation with O3, while displaying negative associations with the other five air quality indicators. These findings contribute to urban environmental planning and the effective management and utilization of solar radiation, thereby providing valuable insights to guide the future development of cross-regional comprehensive energy utilization projects under diverse climatic and geographical conditions. Additionally, they serve as a reference for subsequent research aimed at enhancing the accuracy of global solar radiation prediction models. [ABSTRACT FROM AUTHOR]

As the largest freshwater river flowing through Harbin, the Songhua River is a standby water source. It is very important to know the species and distribution of antibiotic-resistant bacteria (ARB) in the river. In this study, five antibiotics were selected to screen and identify ARB in spring and autumn. The results showed that the concentration of cefotaxime-resistant bacteria was the highest, and the maximum concentration at S6 in spring was up to 1.40 × 104 CFU/mL. In spring and autumn, bacteria resistant to three antibiotics were screened at S1 of the Songhua River, and bacteria resistant to five antibiotics were screened at S6. No multiple antibiotic-resistant bacteria (MARB) were screened in the other four sites in autumn, while MARB were screened in the other three samples except S2 in spring. In all sample areas in spring and autumn, the probability of screening MARB at S1 and S6 was the highest, reaching 100%. The identification results of 16S rDNA polymerase chain reaction (PCR) products of ARB showed that a total of 51 ARB strains from 15 bacterial genera were screened in the Songhua River, of which 20 ARB strains were from Pseudomonas. Among the 15 bacterial genera, bacteria from 8 bacterial genera have pathogenicity. The results of this study revealed the concentration, spatial distribution, and seasonal variation of culturable ARB in the Songhua River, providing data support for the remediation of antibiotic resistance gene (ARG) pollution in the river. [ABSTRACT FROM AUTHOR]

Increasingly, cities worldwide are striving for green travel and slow traffic, and vigorously developing people-oriented urban pedestrian traffic with sustainability has become a fixture in recent discourse. This paper comprehensively considers the sidewalk's facilities environment and the status of pedestrian traffic flow; divides the urban pedestrian road system (UPRS) into five subsystems around the underpass, overpass, crosswalk, sidewalk, and road crosswalk; and introduces the basic structure as well as the function of each system. Then, the indicators are classified into two types of crosswalk facilities and sidewalk facilities, and a comprehensive pedestrian road indicator system with the combination of subjective and objective is established. Consequently, the integration of the fuzzy AHP and DEA-based symmetrical technique for the subjective evaluation indicator combined with pedestrian traffic characteristics is developed. A nine-step semantics scale of relative importance was used so that the symmetry of the response of pedestrian satisfaction was maintained. Fuzzy evaluation based on AHP is further modeled, and the DEA is employed to achieve an overall evaluation of the quality of service (QoS) for UPRS. The applicability of the established evaluation system is finally verified through a real case study in Harbin, China. The serviceability assessment method in this paper provides a new idea for planners to conduct sustainability evaluation for UPRS in future urban renewal development. [ABSTRACT FROM AUTHOR]

In order to reveal the characteristics of the competition and cooperation of multi-modal public transportation in the cities of cold areas and to study the competitive relationship of multi-modal public transportation in cold areas, the urban public transportation system in cold areas is divided into three sub-systems, namely, conventional buses, urban mass transit, and cabs, to analyze the competitive relationship and evolution mechanism of multi-modal public transportation in cities of cold areas. We construct a multi-modal public transit Lotka–Volterra competitiveness model, considering that conventional buses and urban mass transit are mainly dominant in urban public transit systems in cold regions, and introduce the competitive influence effect coefficients and cooperative influence effect coefficients to analyze the mechanism of the evolution of the competitiveness between conventional buses and urban mass transit. The data on traffic supply and demand and travel of the Harbin bus system, a typical city in China, are collected, and the simulation analysis of multi-modal competing relationship and evolution mechanism of conventional bus and urban mass transit competition is carried out, respectively, with Harbin as the research object. The results show that the constructed model can better describe the multi-modal bus competition relationship and evolution mechanism. [ABSTRACT FROM AUTHOR]

Cross-view geolocation is a valuable yet challenging task. In practical applications, the images targeted by cross-view geolocation technology encompass multi-domain remote sensing images, including those from different platforms (e.g., drone cameras and satellites), different perspectives (e.g., nadir and oblique), and different temporal conditions (e.g., various seasons and weather conditions). Based on the characteristics of these images, we have designed an effective framework, Image Reconstruction and Multi-Unit Mutual Learning Net (IML-Net), for accomplishing cross-view geolocation tasks. By incorporating a deconvolutional network into the architecture to reconstruct images, we can better bridge the differences in remote sensing image features across different domains. This enables the mapping of target images from different platforms and perspectives into a shared latent space representation, obtaining more discriminative feature descriptors. The process enhances the robustness of feature extraction for locating targets across a wide range of perspectives. To improve the network's performance, we introduce attention regions learned from different units as augmented data during the training process. For the current cross-view geolocation datasets, the use of large-scale datasets is limited due to high costs and privacy concerns, leading to the prevalent use of simulated data. However, real data allow the network to learn more generalizable features. To make the model more robust and stable, we collected two groups of multi-domain datasets from the Zurich and Harbin regions, incorporating real data into the cross-view geolocation task to construct the ZHcity750 Dataset. Our framework is evaluated on the cross-domain ZHcity750 Dataset, which shows competitive results compared to state-of-the-art methods. [ABSTRACT FROM AUTHOR]

In their natural state, snow crystals are influenced by the atmosphere during formation and multiple factors after landing, resulting in varying particle sizes and unstable particle morphologies that are challenging to quantify. The current research mainly focuses on the relationship between the porosity of compacted snow samples or qualitatively describes snow crystals and their macroscopic physical properties, ignoring that the significant differences in the morphology of snow crystals also affect their physical properties. To quantitatively evaluate the morphology of snow crystals, we employed optical microscopy to obtain digital images of snow crystals in Harbin, utilizing the Sobel and Otsu algorithms to determine the equivalent particle size and fractal dimension of individual snow particles. In addition, the hardness of snow with a density of 0.4 g/cm3 was measured through a penetration test, with an analysis of its correlation relative to particle size and fractal dimension. The results indicated the fractal dimension as an effective parameter for characterizing particle shape, which decreased rapidly over time and then fluctuated within the range of 1.10 to 1.15. During the initial period, natural snow crystals broke down rapidly, leading to an increase in the percentage of natural snow crystals with an equivalent particle size of 0.2–0.4 mm up to 51.86%. After three days, the sintering effect between snow crystals was enhanced, resulting in an even distribution of the equivalent particle size. Finally, multiple linear regression analysis showed a positive correlation between compacted snow hardness and fractal dimension, with a negative correlation between compacted snow hardness and equivalent particle size. These findings offer valuable technical support and data reference for exploring the relationship between snow's mechanical properties and its microscopic particle shape. [ABSTRACT FROM AUTHOR]

Simple Summary: When holocyclic aphids, Aphis glycines Matsumura, were exposed to a diurnal of 35 °C lasting for seven days, the development, reproduction, and morphogenesis were affected significantly. These results are important for predicting the dynamics of A. glycines in this region. This also provides evidence that shows short-term heatwaves are useful for controlling the occurrence of A. glycines. The soybean aphid, A. glycines, is an important soybean pest. Harbin, in the Heilongjiang Province, is an area with increasing temperatures in China that faces frequent short-term heatwaves. In this study, the development, reproduction, and morph differentiation of A. glycines have been studied when they were exposed to diurnal at 35 °C for seven days, beginning at different developmental stages. The nymph stage duration of A. glycines was longer, the adult lifespans and total lifespans were shorter, and their bodies were smaller when exposed to a diurnal of 35 °C beginning at the 1st to 4th stadium. The adult reproduction period was shorter, and the adult fecundity and intrinsic rate of increase were smaller than those of aphids reared at a diurnal of 25 °C. A higher and lower proportion of gynoparae and males were deposited as offspring on day 13 by adults when exposed to diurnal at 35 °C, beginning at the 1st to 4th stadium, respectively, than those of aphids reared at a constant of 20 °C. These results are important for predicting the dynamics of A. glycines in Harbin soybeans. This provides evidence that short-term heatwaves are probably useful for controlling A. glycines, by inhibiting development and male morphogenesis. [ABSTRACT FROM AUTHOR]

China has clearly put forward the strategic goals of reaching the "Carbon Emission Peak" by 2030, and achieving "Carbon Neutrality" by 2060. To achieve these goals, it is necessary to precisely understand the spatial distribution characteristics of historical carbon emissions in different regions. This paper has selected a representative national-level urban agglomeration in China, the Harbin–Changchun urban agglomeration, to study the temporal and spatial distribution characteristics of carbon emissions in its counties. This paper has constructed global and local Moran's I indexes for the 103 counties in this urban agglomeration by using the carbon emission values reflected by night light data from 1997 to 2017 to perform global and local autocorrelation analysis on a spatial level. The results show that: (1) the main characteristic of carbon emission clustering in the Harbin–Changchun urban agglomeration is similar clustering; (2) the changes in carbon emissions of the Harbin–Changchun urban agglomeration have a strong correlation with relevant policies. For example, due to the impact of the "Twelfth Five-Year Plan" policies, in 2013, the global county-level Moran's I index of the carbon emissions in the Harbin–Changchun urban agglomeration decreased by 0.0598; (3) the areas where high carbon emission values cluster together ("High–High Cluster") and low carbon emission values cluster together ("Low–Low Cluster") in the Harbin–Changchun urban agglomeration are highly concentrated, and the clusters are closely related to the development level of different regions. [ABSTRACT FROM AUTHOR]

Rock weathering, an important geological process on the earth's surface, plays a key role in shaping surface morphology, providing nutrients needed by the ecosystem, and regulating the global climate. However, the regimes for controlling rock weathering in different regions are still controversial. In this respect, the heavy minerals, elements, Sr-Nd isotope, magnetic susceptibility, and chromaticity of the granite weathering profile in Harbin, a high latitude area of China, were analyzed for understanding the weathering characteristics and mechanisms of the granite weathering profile in the cold area. The results indicate that the profile underwent strengthened physical weathering (large volumes of cracks in the granite parent rock) and low–moderate chemical weathering (CIA = 56~68). However, the chemical weathering does not clearly affect the composition of the weathering products, making the weathering products a good inheritance from the parent rocks, as evidenced by the binary diagram (e.g., TiO2-Zr, and La/Sc-Co/Th) and geochemical genes (LG01 and LG03). The development process of the weathering profile has been affected by the input of external materials and biological activities, as evidenced by the Sr-Nd isotopic composition, Th/Zr values, chemical depletion fractions, ΔAl/Ti ratios, χfd%, and geochemical genes (LG03). Notably, a progressively decreasing weathering degree with a reduced depth is observed in the profile, which is likely to be related to an addition of external materials and/or effects of biological activities. In addition, the weathering regime of the profile does not vary in geology time, characterized by a kinetic-limited weathering regime with a limited supply. [ABSTRACT FROM AUTHOR]

Subway station entrances serve as crucial links between urban environments and underground transit systems and are particularly vital in cities with cold climates. Specialized design strategies are essential to address user needs and promote safety and comfort, thereby encouraging sustainable travel in harsh winter conditions. This research utilizes data from Harbin and Shenyang, two winter cities in China, to explore the nonlinear influences of subway entrance attributes on passenger satisfaction through the combined use of gradient-boosting decision trees and asymmetric impact-performance analysis. The findings indicate that most key attributes of subway entrances impact passenger satisfaction asymmetrically, highlighting the significance of their hierarchical importance in generating satisfaction. These attributes are categorized into frustrators, dissatisfiers, hybrids, satisfiers, and delighters, based on their asymmetry levels. Considering the current performance of these attributes, the study identifies priority for improvement at Harbin and Shenyang's subway entrances. This aids urban designers and city managers in making informed decisions for urban development and enhancing the overall commuter experience in winter cities. [ABSTRACT FROM AUTHOR]

Biodiversity is profoundly influenced by habitat quality, and Harbin, a provincial capital situated in a cold climate zone, stands out as one of China's regions most susceptible to the repercussions of climate change. To ensure the city's continued sustainable growth, a thorough assessment of habitat quality must be conducted. This study employs a comprehensive approach integrating the InVEST model, the PLUS model, a landscape pattern analysis, geographic detector, and a geographically weighted regression model. The goal is to assess how land use and habitat quality have changed in Harbin City, investigate factors contributing to spatial heterogeneity in habitat quality, thoroughly examine evolutionary patterns under the inertial development scenario from 2030 to 2050, and propose spatial optimization strategies. There are four key findings. First, from 2000 to 2020, agricultural land and forest were Harbin City's two most prevalent land use types. The most notable transition occurred from forest to grassland, and the expansion of construction land primarily resulted from its encroachment into agricultural areas. Second, within the area of study, the landscape heterogeneity increased while simultaneously experiencing a decrease in connectivity, and the landscape had a tendency toward a more fragmented spatial distribution. Third, overall habitat quality rose between 2000 and 2020 but declined between 2030 and 2050. There was a "weak in the west and high in the east" distribution pattern in the spatial heterogeneity of habitat quality. Fourth, population density has the most impact on habitat quality, with the NDVI and GDP close behind. Conversely, precipitation and slope had comparatively smaller influences on habitat quality. Natural factors combined had a primarily favorable influence on habitat quality across the research region in terms of spatial distribution. Conversely, population density had a discernibly detrimental impact. Given these findings, this study suggests targeted strategies to optimize habitat quality. These recommendations are relevant not only for biodiversity conservation but also for the development of an ecologically sustainable community, particularly in a cold climate region. [ABSTRACT FROM AUTHOR]

Urban–rural integration relies on the rational flow of factors between urban–rural areas. Land represents a closely related factor between urban–rural areas, so the effective utilization of land resources can promote the flow of urban–rural factors. Therefore, there is a certain correlation between land use function and urban–rural integration. The purpose of this study is to explore the coupling and coordination relationship between the two systems and to find out the spatial–temporal differentiation characteristics in the process of land use function and urban–rural integration. The main conclusions are as follows: (1) The comprehensive level of land use function and urban–rural integration in Heilongjiang Province shows an overall upward trend, but there is a large differentiation on a municipal scale. (2) The coupling coordination degree of the two systems in Heilongjiang Province shows a spatial distribution pattern of "high in the north and low in the south, high in the middle and low in the east and west". From 2013 to 2022, except for Harbin and Yichun, the overall trend in other regions is gradually upward. (3) The obstacle degree analysis of land use function and urban–rural integration in Heilongjiang Province shows that there is a close correlation of obstacle factors between the two systems. [ABSTRACT FROM AUTHOR]

As one of the major new agricultural business entities, agricultural leading enterprises (ALEs) are responsible for ensuring national food security, leading agricultural and rural modernization, and increasing farmers' employment prospects and incomes. From the perspective of headquarters and branches, this study used a point pattern analysis, the local Moran's index, the rank-size rule, and the geographical detector to depict the spatial pattern of ALEs in Heilongjiang Province, detect influencing factors, and reveal the spatial layout mechanism. The main conclusions are as follows. (1) ALE headquarters and branches in Heilongjiang Province had different location requirements, and their layout orientation, clustering areas, and influencing factors were different. (2) The headquarters displayed a pronounced urban and agglomeration orientation, while branches exhibited a significant farm dependence and raw material orientation. (3) Both the headquarters and the branches showed a significant trend towards spatial clustering. The headquarters were mainly in the Harbin municipal district and surrounding counties, including Wuchang, Zhaodong, and Beilin, which showed a high–high cluster pattern. The branches were mainly in the Sanjiang Plain. Tongjiang, Fujin, Hulin, Mishan, Raohe, Baoqing, and Suibin showed a high–high cluster pattern, while the Harbin municipal district and Bei'an showed a high–low outlier pattern. (4) The ALEs' regional connection network in Heilongjiang Province was radially distributed with the Harbin municipal district as the centre. The agricultural reclamation system deeply influenced it. (5) The number of supporting enterprises, number of permanent residents, gross domestic product, railway mileage, number of people with Bachelor's degrees or above, and distance from the provincial capital were the main influencing factors of the headquarters spatial pattern in Heilongjiang Province. The number of state farms in Heilongjiang Province, the per capita grain yield, highway mileage, and distance from the provincial capital were the main influencing factors of the branch spatial patterns in Heilongjiang Province. The interaction results indicated that the explanatory power of two-factor interaction was stronger than that of a single factor regardless of headquarters or branches, and most interaction types were bilinear enhancements. This study aims to provide a decision-making reference for the long-term development of ALEs in Heilongjiang Province at the present stage and accelerate the development of agricultural industrialization in major grain-producing areas. [ABSTRACT FROM AUTHOR]

Near-surface PM2.5 concentrations have been greatly exacerbated by urban land expansion and dense urban traffic. This study aims to clarify the effects of multiple factors on near-surface PM2.5 concentrations from three perspectives of background climatic variables, urban morphology variables, and traffic-related emission intensity. First, two case areas covering multiple local blocks were selected to conduct mobile measurements under different climatic conditions. The observed meteorological parameters and PM2.5 concentration were obtained through GIS-based imaging. These interpolation results of air temperature and relative humidity reveal highly spatiotemporal diversity, which is greatly influenced by artificial heat emissions and spatial morphology characteristics in local areas. The PM2.5 concentration on measurement days also varies considerably from the lowest value of 44~56 μg/m3 in October to about 500 μg/m3 in December in Harbin winter and ranges between about 5 μg/m3 and 50 μg/m3 in Guangzhou summer. The correlation analysis reveals that both the climatic conditions and urban morphology characteristics are significantly correlated with local PM2.5 concentration. Especially for Guangzhou summer, the PM2.5 concentration was positively correlated with the street traffic emission source intensity with correlation coefficient reaching about 0.79. Multivariate nonlinear formulas were applied to fit the association between these factors and PM2.5 concentration with higher determined coefficients. And optimization strategies are thus suggested to improve the urban air quality in local-scale areas. This attribution analysis contributes to environmentally friendly urban construction. [ABSTRACT FROM AUTHOR]

This study analyzed frost formation data provided by the Harbin Meteorological Bureau and considered geographic factors, temperature, and population density. Various analytical methods, including linear fitting, the Mann–Kendall mutation test, the Pettitt method, and the sliding t-test, were employed to identify the temporal and spatial changes as well as the effects of these factors on frost dates in Harbin. The study shows that the first FSD occurred on 18 August, in both 1966 and 1967, which was the 255th day. The latest FSD was observed on 10 October 2006, which was the 283rd day. The earliest occurrence of an FED was on 24 April 2015, which was the 114th day, and the latest was on 21 April 1974, which was the 141st day. The highest number of frost days occurred in 2012, with 161 days, whereas the shortest year was 1966, with only 123 frost days. Throughout the study period, the FSD increased by 7.8 days at a rate of −1.27d/10a, the FED increased by 10.9 days at a rate of 1.77d/10a, and the FFS increased by 18.9 days at a rate of 3.05d/10a. The propensity rates of the FSD and FFS at each location in Harbin indicate an upward trend, while for the FED, certain locations display an upward trend. In general, the FSD has exhibited a delayed trend, the FED has shown an earlier trend, and the FFS has experienced an extended trend. With one-way linear regression, the FSD exhibited an increasing trend at each site, while the FFS also indicated a similar trend, and the FED showed an overall decreasing trend. Throughout the study period, a change was observed in the FSD in 2000, resulting in an average arrival time of the 265th day, or 22 September, of that year. Subsequently, post mutation, the average arrival time of the FSD in the study area was the 272nd day, or 29 September, of that year. In 2006, the FED also underwent a change, with the average arrival time in the study area being the 128th day, or 4 April, of that year. After the change, the average arrival time of the FED in the study area was the 121st day, i.e., 8 April. In 1 April 2004 of that year saw a change in the FFS. Prior to the change, the FFS in the study area averaged the 137th day, whilst following the change, the FFS in the study area averaged the 150th day. The FSD and FFS within Harbin exhibit a negative correlation with latitude and a positive correlation with temperature. Additionally, the FED displays a positive correlation with latitude and a negative correlation with temperature. As the FSD, FED, and FFS in central Harbin are the earliest, latest, and longest, the Pearson correlation coefficient method and multiple regression cannot adequately reflect the effect of longitude. [ABSTRACT FROM AUTHOR]

The low-carbon retrofitting of industrial heritage communities is an important issue for reducing urban carbon emissions. Previous research on the judgment of heritage elements and carbon emission factors of industrial heritage communities lacked the construction of elements within the space, and the value judgment of conservation and the determination of low-carbon factors lacked a systematic network analysis. Carbon spatial networks as a systematic approach can systematically harmonize the contradictions between "conservation–transformation–low carbon" while considering the spatial and temporal carbon emissions of nodes. This research uses hierarchical analysis to analyze the value of heritage elements and locate them in space, then combine the elements that affect carbon activities in space to form carbon space nodes integrated with heritage conservation elements, and analyze the links between nodes to form a carbon space network. Then, this research uses a carbon spatial network to dissect the structure of carbon emissions, calculate the carbon activity at nodes, and reflect it into a parameterized platform to guide designers. After that, this research selected 16 industrial heritage communities in the severe cold region for the carbon activity measurement of carbon spatial network node elements in the operation stage and conducted a correlation analysis to obtain a correlation matrix model of node elements and carbon activities. Within the constraints of heritage element protection, the results show that the volume ratio, green area ratio, and building density of the carbon spatial network model have the greatest influence on its carbon performance, followed by porosity and road density. Through case simulation verification, the floor area ratio of industrial heritage communities should be controlled between 2.1–2.5, the number of residential building floors should be 7–14, the road network density should be 4.16–4.50%, the green space ratio should be 20–35%, and the porosity should be 35–45%. Taking the three major power road communities in Harbin as an example, retrofit measures were decided by reference to relevant parameter control intervals, resulting in a 21.1% reduction in energy consumption, an approximate 32.7% reduction in carbon emissions, and a 7.3% reduction in the annual percentage of hours in extreme hot and cold environments. [ABSTRACT FROM AUTHOR]

Creating a comfortable indoor environment in education buildings is an important design objective. Climate change has resulted in rising summer indoor temperatures in the severe cold regions of China, and evidence of summer overheating risk in these regions has not yet been fully investigated. This study presents evidence of overheating in a university building in a severe cold region of China, discusses the potential of integrated shading devices for mitigating overheating, and proposes design ideas for the application of shading devices. Temperature monitoring and simulation were performed in a university building with natural ventilation located in Harbin, and various configurations of integrated shading devices were simulated using IES Virtual Environment software. The results demonstrate that 69% of classrooms were overheated; furthermore, south-facing classrooms could be overheated for up to 152 h during summer occupancy hours. This study finds that integrated shading devices reduce overheating hours by up to 59.2%. The design of appropriate parameters for shading devices can effectively improve indoor thermal comfort while maintaining daylight levels and controlling the increase in energy consumption. The methodology and results presented in this study offer a reference point and practical guidance for mitigating regional overheating, aiming to promote the improvement of regional standards and optimisation of thermal environments in the severe cold regions of China. [ABSTRACT FROM AUTHOR]

Soil physical quality (SPQ) is a limiting factor affecting crop production. However, the impact of gully erosion on the SPQ index S, defined by Dexter as the inflection point of the soil water retention curve (SWRC), remains unclear, especially when considering different latitudinal regions. This study aimed to apply Dexter's S-theory to evaluate the distribution of index S in black soils adjacent to various gully positions and investigate its relationship with bulk density (Bd), soil organic matter (SOM), and particle percentage. Soil properties (SWRC, Bd, SOM, and particle percentage) from nine gullies in croplands in three latitudinal regions (Harbin, Hailun, and Nenjiang in Heilongjiang province) were determined at the gully edge (GE0) and 50 m beyond the edge into the croplands (GE50) at the following gully units: head, mid-upper, middle, mid-lower, tail, and conjunctions between main gully and gully branch. The S-index was calculated using parameters such as n, θs, and θr, with SWRC data fitted into the van Genuchten model. The results showed spatial variations in the S-index across latitudinal regions, with slightly higher S-values in Harbin than in Hailun and Nenjiang. The S-index also showed noticeable differences at GE0 and GE50 and at the junctions between the main gully and its branches. Approximately 51% of the samples at GE0 and 28.2% of the samples at GE50 had S-values below 0.035, which Dexter proposed as the boundary between good and poor SPQ, indicating a degradation of SPQ at the gully-surrounding areas. A decreased S-index in the gully vicinity was significantly (p < 0.05) associated with increased bulk density (1.33 vs. 1.21 g cm−3 for GE0 and GE50) and decreased SOM (36.80 vs. 39.36 g kg−1 for GE0 and GE50). In summary, this study indicates that gully erosion affects the farmland S-index at the gully-surrounding areas through SOM and Bd. Accordingly, measures suited to the increase in the S-index of the gully-surrounding areas may be implemented to maximize the crop yield of farmlands. [ABSTRACT FROM AUTHOR]

An energy storage system works in sync with a photovoltaic system to effectively alleviate the intermittency in the photovoltaic output. Owing to its high power density and long life, supercapacitors make the battery–supercapacitor hybrid energy storage system (HESS) a good solution. This study considers the particularity of annual illumination due to climate conditions in Harbin, China. A global optimal PV-HESS sizing method is proposed by constructing a PV-HESS operating cost model and taking the annual system operating cost as the objective function. To consider the effect of battery life degradation due to different charge and discharge rates and charge and discharge times, a semi-empirical model based on the Arrhenius model was used to quantify the battery life degradation. Based on the effects of different seasons and different photovoltaic panel sizes, batteries, and supercapacitors on the optimization results, four scenarios are proposed. The feasibility of the system configuration corresponding to the four scenarios is discussed, and an optimal sizing configuration of the system is obtained. The simulation results show that the proposed method can effectively balance the degradation of the ESS due to irregular charging and discharging and determine the minimum operating cost and a reasonable sizing configuration of the system. [ABSTRACT FROM AUTHOR]

This paper first analyzes the climate characteristics of five typical cities in China, including Harbin, Beijing, Shanghai, Shenzhen and Kunming. Then, based on Grasshopper, Ladybug and Honeybee analysis software, according to the indoor layout of typical residential buildings, this research extracts design parameters such as the depth and width of different rooms and their window-to-wall ratios etc., to establish a climate responsive optimization design process with indoor lighting environment comfort, with heating and cooling demand as the objective functions. Meanwhile, based on Monte Carlo simulation data, ANN (Artificial Neural Network) is used to establish a prediction model to analyze the sensitivity of interior design parameters under different typical cities' climatic conditions. The study results show that the recommended values for the total width and total depth of indoor units under the climatic conditions of each city are both approximately 14.97 m and 7.88 m. Among them, under the climatic conditions of Harbin and Shenzhen, the design parameters of residential interiors can take the recommended value of UDI optimal or nZEB optimal. While the recommended values of window-to-wall ratios for the north bedroom, master bedroom and living room in Shanghai residential interiors are 0.26, 0.32 and 0.33, respectively. The recommended value of the window-to-wall ratio of the master bedroom in Kunming residences is 0.36, and that of the remaining rooms is between 0.15 and 0.18. The recommended values of window-to-wall ratios for the master bedroom and living room in Beijing residences are 0.41 and 0.59, respectively, and that for the remaining rooms are 0.15. The multi-objective optimization process based on parametric performance simulation used in the study can effectively assist architects in making energy-saving design decisions in the preliminary stage, allowing architects to have a case to follow in the actual design operation process. [ABSTRACT FROM AUTHOR]

In China, the post-Winter Olympics era has seen the rapid development and promotion of ice rinks with air-supported membrane structures. With the rise of large indoor spectator areas in ice rinks, thermal comfort needs in spectator areas are receiving more and more attention. The satisfaction of thermal comfort needs is crucial to people's health and well-being, so further study of the issue of thermal comfort in such spectator areas is needed. Unfortunately, models currently used to evaluate the thermal comfort of traditional building envelopes are not applicable to air-supported membrane-envelope ice rinks. Researchers need to focus on the internal thermal comfort needs of air-supported membrane envelopes for spectator areas. The aim of this research was to establish a thermal comfort model to provide exact temperature-range recommendations for spectator areas in air-supported membrane ice rinks. The indoor thermal-environment parameters of the ice rink in Harbin were measured from 2 January to 15 January 2023. To elicit data on spectators' actual thermal sensations in the ice rink, a field questionnaire was administered. By modifying the expectancy factor, an extended predicted thermal comfort model was established. The results suggested that the operative temperature required to meet spectators' thermal comfort needs in the case study ice rink ranged from 17 °C to 26 °C. The results of the study offer specific insights into the indoor thermal comfort needs of air-supported ice rinks and provide a more accurate temperature-setting reference for the healthy and energy-efficient development of such rinks. [ABSTRACT FROM AUTHOR]

The integrated energy system (IES) is an efficient method for improving the utilization of renewable energy. This paper proposes an IES based on fuel, wind and solar energies, following an optimization study focused on determining optimal device capacities. The study included gas turbines, wind turbines, solar photovoltaic panels, ground source heat pumps, absorption chillers/heaters, batteries, and thermal storage. Objectives were incorporated into the optimization model for the overall performance of the IES; these included the primary energy saving rate, annual cost-saving rate, and carbon dioxide emission reduction. Then, the nondominated sorting genetic algorithm II was employed to solve the optimization problem for multiple objectives. Ultimately, the verification and sensitivity analyses of the optimization method were achieved by a case study of hospital buildings in Harbin. The optimization results indicated a primary energy saving rate, annual cost saving rate, and carbon dioxide emission reduction rate of 17.3%, 39.8%, and 53.8%, respectively. The total installed capacity for renewable energy generation accounted for 64.5% of performance optimization. Moreover, the price of natural gas affected the economic indicators of the IES–but failed to impact energy consumption indicators. [ABSTRACT FROM AUTHOR]

High heating expenses are observed in numerous Chinese rural houses located in severe cold regions due to the high heating demand, inferior envelope performance and low-efficiency heating equipment. The local traditional heating methods include Chinese Kangs and coal boilers with water-based radiators. The intermittent operation and manual regulation of these systems result in significant temperature differences and inadequate thermal comfort. This study presents the cost-optimal envelope renovation solutions with the minimized lifecycle cost (LCC) during a 20-year discount period and CO2 emissions of annual delivered energy consumptions. A single-family detached rural house in Harbin was used as a case building, illustrating the typical state of comparable houses in this climate context. Simulation-based multi-optimization analysis was conducted in this study using the building simulation tool IDA ICE and its integrated optimization tool AutoMOO. The results indicate that the cost-optimal renovation solutions with intermittent and continuous heating can cut CO2 emissions by 30% and 40%, respectively. The LCC with intermittent heating is still 7% greater than its pre-renovation case, which may require external financial support to encourage the renovation conduction, while the LCC with continuous heating decreased by 8% after renovation. According to the comparison results, cost-optimal solutions have significant advantages in both reductions of LCC and CO2 emissions over standard-based solutions. Moreover, utilizing intermittent heating is more effective than continuous heating in demonstrating the positive impacts of envelope renovation on increasing average temperature, decreasing temperature differences and lowering occupied time at low thermal comfort levels. [ABSTRACT FROM AUTHOR]