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• To solve the forecasting problems of time-lead and nonlinearity in a system, a novel grey multivariable model is proposed. • To reduce the morbidity of the model, the solution of the proposed model is deduced through a derivation method. • The grey prediction evolution algorithm is employed to find the optimal value of parameters. • The validity of the new model was verified by three examples and applied to house price forecasting. Time lags or leads and non-linearity of complex systems are critical to address in accurate scientific prediction. However, few studies have focused on time-lead and nonlinear models with limited information. Therefore, this paper aims to develop a novel grey multivariate model with time-lead operator τ and nonlinear factor r from the perspective of this problem. Next, the solution of the proposed model is deduced through a derivation method to reduce the morbidity of the model. Then, the parameter identification of the model is given on the basis of the least-squares method. The grey prediction evolution algorithm is employed to find the optimal value of parameters τ and r to meet the minimum errors. Finally, house prices of Wuhan, Beijing and Shanghai in China are performed to verify the validity and reliability of the new model. The results demonstrate the model we proposed has satisfactory prediction precision, demonstrating that time-lead and nonlinear factor in the model is reasonable. At the end of the paper, the house prices of these three cities from 2022 to 2028 are also predicted. The average annual growth rate in the three regions is 2.49%, 3.57% and 2.97%, respectively. These results are useful to policy analysis regarding house price correlations. They provide insights for market investors and policy makers. [ABSTRACT FROM AUTHOR]

To achieve carbon neutrality quickly and deal with urban greenhouse effect, it is necessary to study the energy consumption of urban buildings. Energy consumption prediction is an important step in planning and managing energy use in buildings. At present, few studies have comprehensively considered the relationship between geometric features, functional types, location and energy use of buildings in urban built-up areas. In this paper, a spatial data-driven framework is introduced for the analysis and assessment of building energy consumption. The framework is grounded in the building centroid and is combined with single photon radar and point of interest data through the utilization of the nearest neighbor classification algorithm. Two megacities, Beijing and Shanghai, are taken as examples to illustrate the method and to generate the regional building energy use database. The results show that: a) building physical feature (geometric form, functional type) have a significant impact on energy consumption, and energy consumption is correlated with the economic level of the region; b) Energy use in urban built-up areas has obvious spatial agglomeration characteristics, and the siphon effect is obvious in region with high energy consumption. The contribution of the framework is to provide insights into the feasibility of employing multiple spatial data fusion for the analysis of energy consumption within urban built-up areas. This can be employed to address energy planning concerns and help promote sustainable environmental practices in urban areas worldwide. • This paper attempts to provide a feasible framework for analyzing urban building energy use by utilizing real-time urban semantic perception information and building features. • The proposed framework have comprehensively considered the relationship between geometric features, functional types, location and energy use of buildings. • The proposed methodology can obtain regional energy consumption stocks and produce spatial distribution results, thus improving the interpretability of the data. • The results show that energy use in urban built-up areas has obvious spatial agglomeration characteristics, and the siphoning effect is obvious in regions with high energy consumption. [ABSTRACT FROM AUTHOR]

• This paper examines the integrated optimization of train stopping plan and seat allocation. • The integrated optimization problem is formulated as a mixed-integer mathematical model. • The integrated optimization approach improves efficiency against separate optimization of stopping plan and seat allocation. • Numerical studies were conducted on Zhengzhou-Xi'an and Shanghai-Beijing high-speed railway corridors. This paper examines the integrated optimization of train stopping plan and seat allocation scheme in railway systems, where equilibrium passenger travel choice under elastic demand is considered. The integrated optimization problem is formulated as a non-concave and non-linear mixed-integer mathematical model, where the objective is to maximize the system net benefit considering ticket revenue, consumer surplus, and cost associated with train stoppings. The integrated optimization model can be reformulated into a mixed-integer linear programming (MILP) model based on a series of linearization, relaxation, and outer-approximation techniques, which can then be solved by commercial MILP solvers (e.g., GUROBI). We also compare the integrated optimization approach with that when the train stopping plan and seat allocation are optimized separately and identify the potential benefits. Numerical studies have been conducted on a small-scale example, the Zhengzhou-Xi'an and Shanghai-Beijing high-speed railway corridors to illustrate the proposed model and solution approach. [ABSTRACT FROM AUTHOR]

• CO 2 air conditioning systems driven by compressed air engines are designed innovatively. • CO 2 air conditioning system driven by compressed air engine can significantly reduce running costs. • Combination of air conditioning system and compressed air storage is promising. Traditional building air conditioning uses electricity or thermal energy to drive the refrigeration cycle. The energy released by the expansion of compressed air can also be used for driving the refrigeration cycle. Moreover, the expanded low-temperature air can be used in the air conditioning system too. In this paper, three forms of CO 2 air conditioning systems driven by novel reciprocating piston compressed air engines were designed, namely EAGC (Exhaust Air for Gas Cooler), EAS (Exhaust Air for Sub-cooler), and EASC (Exhaust Air for Space Cooling), to analyze the performance and economics of CO 2 air conditioning systems combined with compressed air energy storage technology. Twenty-seven typical cities were selected in different climate regions in China to evaluate the systems' performance and running cost under outdoor temperature changes and different electricity prices. The results show that compared with the electricity-driven CO 2 air conditioning system, the three systems can greatly improve the system COP (Coefficient of Performance) but still cannot reach the performance level of the conventional freon refrigeration systems. However, in cities like Beijing and Shanghai with the large peak-to-valley electricity price difference, EASC system compared to the electricity-driven R410A air conditioning system running costs are lower, the average running cost per hour can be saved 11.96% and 16.35%, respectively. This means that the CO 2 air conditioning system with compressed air energy storage technology has a certain economic application value and can be popularized on reasonable occasions. This innovative system design can help solve the contradiction between supply and demand of building energy, realize leisure energy consumption, and reduce the economic cost of energy consumption on the demand side. [ABSTRACT FROM AUTHOR]

Pairs trading is one of the mainstream statistical arbitrage strategies in current financial market practice that can seize possible arbitrage opportunities caused by mispricing between similar assets. Based on the theory of statistical arbitrage and the similar attributes of carbon emission allowances traded in different carbon markets, this paper studies the applicability of the pairs trading strategy among different pilot markets in China. The novelty and possible contribution of this paper are as follows. Firstly, this paper extends the statistical arbitrage-based pairs trading framework to the analysis of carbon market transactions in China, which broadens the understanding of the correlation between China's carbon markets. Secondly, this study explores the arbitrage opportunities among China's regional carbon markets that have not been revealed by previous studies. Thirdly, based on the pairs trading analytical model adopted in this study, this paper further investigates the operation characteristics of China's carbon markets and the interaction between markets, as the sensitivity of strategy performance to the key parameters is also discussed. The results show that arbitrage based on pairs trading is profitable. In the baseline case, the annualized arbitrage returns between the Shanghai emission allowance and Beijing emission allowance is about 9.11%, the highest among all pairs. However, there is almost no pairing relationship between the Tianjin carbon market and other markets. By discussing the time distribution of arbitrage signals generated by the pairs trading strategy, it is found that most signals are sent out during the inactive trading period in a compliance cycle. The conclusions provide valuable insights for formulating relevant carbon market regulatory policies and investors' participation in arbitrage activities in China's carbon trading markets. • The application of the pairs trading strategy is extended to the Chinese carbon markets. • Based on relative value arbitrage theory, arbitrage opportunities between markets are examined. • Pairs trading strategy can also yield sustainable and distinctive returns in the Chinese carbon markets. • Arbitrage trading between the Shanghai and Beijing markets may yield promising annualized returns with about 9.11%. [ABSTRACT FROM AUTHOR]

[Display omitted] • A solar energy system with hydrogen energy storage and alkaline fuel cell is proposed. • An optimization model base minimum life cycle cost is developed by Getopt. • The performance of solar energy system without and with electrical storage device are compared. In this paper, a novel solar energy system with hydrogen energy storage and alkaline fuel cell is developed in TRNSYS. The solar energy system without electrical energy storage and solar energy system with battery energy storage are established as the reference systems. The life cycle cost is chosen as the optimal objective, and different operating strategies are developed for the proposed system and the reference systems. The optimal variables and dynamic analysis can be obtained after optimization. Various evaluation criteria, including electricity coverage ratio, annual carbon dioxide emission and levelized cost of energy, are used to comprehensively assess the overall performance of the proposed system and the reference systems. Beijing and Shanghai, which belong to cold region and hot-summer and cold-winter region respectively, are chosen as the study sites for case study. The results show that the proposed system has the lowest life cycle cost, which is 186,484.36 USD and 261,467.43 USD in Shanghai and Beijing, respectively. The proposed system has the highest electricity coverage ratio (which is more than 0.5 for most time of the year), the lowest annual carbon dioxide emission (which is 19,099.34 m3 in Shanghai and 31,525.96 m3 in Beijing) and the lowest levelized cost of energy (which is 0.12 USD/kWh in Shanghai and 0.08 USD/kWh in Beijing). [ABSTRACT FROM AUTHOR]

Accurate change detection of built-up areas (BAs) fosters a comprehensive understanding of urban development. The post-classification comparison (PCC) is a widely-used change detection method by classification and temporal comparison. For classification, image-level labeling is an efficient alternative to pixel-level one for pixel-wise weakly supervised segmentation, which frequently applies pixel-level pseudo labels generated from class activation map (CAM) to train semantic segmentation networks. CAM can be obtained from classification networks trained with image-level labels and can indicate the spatial location of objects. The existing studies are subject to the following issues: 1) They only rely on the single-scale and low-resolution CAM, but ignore the multi-scale property of BAs; 2) Pixel-level pseudo labels usually contain noises (e.g., omissions and false alarms); 3) The temporal correlation between multi-temporal images is less considered in PCC. To address these limitations, this paper proposed a multi-scale weakly supervised learning method, which utilized a large number of single-temporal high-resolution images and image-level labels to detect BA changes. This method consisted of three modules: 1) multi-scale CAM for BA pseudo label generation; 2) adaptive online noise correction for BA detection; and 3) generation of reliable pseudo labels for BA change detection. Based on ZY-3 images (2.5 m), we constructed the first multi-view datasets for both BA detection and change detection. Each ZY-3 image includes a multi-spectral image with red, green, blue, and near-infrared bands and a multi-view image with nadir-, forward-, and backward-views. The BA detection dataset contained 86,166 image-level samples (256 × 256 pixels for each sample), covering 48 major cities in China, while the BA change detection dataset consisted of ZY-3 bi-temporal images at rapidly urbanizing areas (i.e., Beijing and Shanghai). Experiments showed that the proposed method can detect BA changes and suppress pseudo changes effectively, yielding 88.2% F1-score in BA detection and 79.3% for Shanghai and 78.5% for Beijing in change detection. Further analysis demonstrated the proposed method to be advantageous in the following two fronts: 1) the image-level weak labels can achieve pixel-wise BA change detection at low cost; and 2) the multi-scale CAM and temporal correlation are effective in the scenarios with limited labels. Datasets and codes will be accessed at https://github.com/lauraset/MSWS. • A multi-scale weakly supervised method for built-up area change detection. • The first multi-view built-up area detection and change detection datasets. • Multi-scale class activation maps for generating pixel-level pseudo labels. • Adaptive online noise correction for obtaining reliable built-up areas. • Reliable change pseudo labels for training a change detection network. [ABSTRACT FROM AUTHOR]

• Present a new cyclic train timetabling model based on extended time-space network. • Decompose the cyclic train timetabling model through Lagrangian relaxation and ADMM. • Solve each train-specific sub-problem efficiently with forward dynamic programming. • Compare with the PESP-based model on a set of real-world instances. The cyclic train timetabling problem aims to synchronize limited operational resources toward a master periodic schedule of transport services. By introducing an extended time-space network construct, this paper proposes a new type of integer programming model reformulation for the cyclic train timetabling problem on a double-track railway corridor at the macroscopic level. This reformulation method also holds the promises to be applied in a broader set of routing and scheduling problems with periodic activity requirements. We also hope that this space-time network extension technique, as a special version of variable splitting methods in the dual decomposition literature, could potentially bridge the modeling gaps between cyclic and non-cyclic timetables. Specifically, the existing mathematical programming model for the periodic event scheduling problem (PESP) is transformed into a multi-commodity network flow model with two coupled schedule networks and side track capacity constraints. In addition, two dual decomposition methods including Lagrangian relaxation and Alternating Direction Method of Multipliers (ADMM), are adopted to dualize the side track capacity constraints. For each train-specific sub-problem in an iterative primal and dual optimization framework, we develop an enhanced version of forward dynamic programming to find the time-dependent least cost master schedule across the time-space network over multiple periods. ADMM-motivated heuristic methods with adjusted penalty parameters are also developed to obtain good upper bound solutions. Based on real-world instances from the Beijing-Shanghai high-speed railway corridor, we compare the numerical performance between the proposed reformulation and the PESP model that involves the standard optimization solver. [ABSTRACT FROM AUTHOR]

• City-centric global multi-region input-output models for Beijing and Shanghai are developed. • Factor contribution and critical path analysis are adopted. • Sector aggregation effect varies across sectoral datasets. Sector aggregation under the input-output framework may lead to deviation in results and the lack of detailed sectoral information, which hinder the targeted implementation of accurate sectoral adjustment policies. This paper explores the effects of sector aggregation on the embodied carbon emission of the residential consumptions of Beijing and Shanghai based on the city-centric global multi-region input-output (CCG-MRIO) model. Integrating with structural path analysis and structural decomposition analysis, the impacts of sector aggregation on the identifying of critical emission transmission paths and driving forces are also revealed. Three sector aggregation datasets are discussed to track the sector aggregation effect in 2012 and 2017. The findings show that the carbon emission results at 8 sector level better align with the results at the 22 sector level than those at 32 sector level. Moreover, sector aggregation will lead to the absence of some critical carbon transmission paths, some factor contributions on carbon emission also changed their directions at different sector levels. On the basis of clarifying the sector aggregation effect on embodied carbon emission, the research results provide a reference for similar studies to select the appropriate level of sector aggregation, to realize the goal of simplifying the calculation or gaining more detailed sectoral emission information. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we first analyze the 5 most cited papers with the title containing “Urban ecosystem health” in Chinese academic journals, and 5 newer papers retrieved from the CSSCI (Chinese Social Sciences Citation Index). The results show that the number of indicators to be used together in more than three papers is 28, and then we select 27 of them to assess Beijing and Shanghai's urban ecosystem health from 2000 to 2011. Secondly, when we standardize the original data, the worst value adjustment coefficient is introduced innovatively. Thirdly, using the entropy method, the weights of concrete indicators of Beijing and Shanghai in the different adjustment coefficients are calculated respectively. Fourthly, based on the fuzzy matter-element method, using the Hamming approach degree, the two cities' ecosystem health index and the contribution value to overall health index from each component are calculated. Lastly, using gray prediction model, the evolutionary time response sequence function of Beijing and Shanghai's urban ecosystem health index is identified, and thus both cities' urban ecosystem health is predicted. [Copyright &y& Elsevier]

Portals are the transition spaces between paths and places in an urban environment such as the entrance to a square from a connecting street. This paper aims to explore different forms of portals by considering their relationship with places. In doing so, a people-generated image analysis was adopted for two case studies conducted in popular Chinese recreational venues: Sanlitun Village, Beijing; and Xintiandi, Shanghai. Through an analysis of nearly 53,000 Instagram photographs, three different roles that a portal can fulfil are identified and defined as the 'doorway', the 'showroom', and the 'place'. These typologies are derived from a deeper understanding of urban space through the 'eyes of the users', and this knowledge can in turn influence the design process for the public realm and urban spaces. Permissions from joannahiew and chulheepark are shown below (my Instagram ID is joomoly). Unlabelled Image • Portals are transition spaces providing an interactive preview of adjacent places. • There are three types of portals identified: the 'doorway', the 'showroom', and the 'place'. • The 'doorway' allows active and passive participation to coexist; it can be connected with any place. • The 'showroom' enables passive participators to collect information; it suits the place with a thematic expression. • The 'place' encourages people to attend events and build relations with surroundings; it suits the place of participation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Propose variational mode decomposition optimized by capuchin search algorithm. • Propose a prediction model of optimized LSTM by pelican optimization algorithm. • Consider error sequence, and propose the error correction module CVMD-POA-LSTM. • Propose a new hybrid prediction model for PM2.5 concentration, named CEEMDAN-ApEn-CVMD-POA-LSTM-EC. • In this paper, all data and code links are shared on GitHub. With the acceleration of urbanization leading to a general decrease in air quality, accurate PM2.5 concentration prediction is of the utmost practical meaning for the control and prevention of air pollution in the region. Therefore, a new hybrid prediction model for PM2.5 concentration based on complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN), approximate entropy (ApEn), variational mode decomposition optimized by capuchin search algorithm (CVMD), long short-term memory optimized by pelican optimization algorithm (POA-LSTM) and error correction (EC), named CEEMDAN-ApEn-CVMD-POA-LSTM-EC, is proposed. First, CEEMDAN is used to acquire a limited amount of intrinsic mode functions (IMFs). Second, calculate ApEn value for each IMF component, and divide each IMF component into high-complexity and low-complexity components by the size of ApEn values. Third, variational mode decomposition optimized by capuchin search algorithm (CVMD), named CVMD, is proposed. CVMD is used as a secondary decomposition method to further decompose high-complexity components adaptively into a finite number of IMFs. Fourth, long short-term memory optimized by pelican optimization algorithm, named POA-LSTM, is proposed. POA-LSTM predicts all IMF components, and the results of their predictions are combined to generate the original prediction results. Final, error sequence is decomposed and predicted again by the EC module CVMD-POA-LSTM to obtain prediction results of error sequence, and final prediction results are acquired by combining original prediction results and prediction results of error sequence. The datasets in Beijing, Shanghai, and Xi'an were selected for simulation experiments to demonstrate the superiority of the proposed model. Taking Beijing as an example, RMSE, MAE, MAPE and R2 values are 1.9947, 1.5577, 0.1157 and 0.9947, which are superior to other comparison models and have the best performance. [ABSTRACT FROM AUTHOR]

Although urban land leasing is supposedly a local government matter, local leaderships' proactive pursual of economic growth for their career advancements can sometimes be at odds with national policies. Yet, how land conveyance decisions are made in midst of the implementation of national policies and land financing has been a rather overlooked aspect in the studies of China's land market. Hence, this paper explores this issue through a study of land conveyance decisions in Beijing and Shanghai's residential and commercial land markets from 2007 to 2018, and their subsequent land price effects. Deploying endogenous treatment effect models, it is revealed that land conveyance decisions in Beijing were highly subject to national policies and the status of its City Party Secretary, but not in Shanghai. Also, the use of Guapai resulted in higher residential and commercial land prices in Shanghai, but lower prices for Beijing's commercial land parcels. The findings indicate that Beijing, due to its closer proximity to the Central Government, appears to have stringently followed the national policy directions, whereas land officials in Shanghai seem to have had a higher degree of autonomy in their decisions. Additionally, the contrasting price effect of Guapai on land prices for residential and commercial land parcels enabled Beijing's government to compensate for the latent losses in land revenue when leasing residential land parcels, due to Nation #10, by leasing commercial parcels at higher prices via tender. [ABSTRACT FROM AUTHOR]

[Display omitted] • The concept of absolute threshold of cooling (ToC abs) is defined and determined. • The cooling intensities of different types of landscape patches were reclassified. • The effects of spatial patterns on LST of different landscape patches were studied. • The impacts of neighboring greenspace proportion on land patch LST were quantified. • The methodology can be applied in other cities to achieve climate adaptive planning. Increasing the amount of blue-green spaces has been recognized as an effective strategy to mitigate the urban heat island (UHI) effect. Specific quantitative and actionable landscape mitigation strategies for different land-use and land-cover (LULC) types to cool down cities, have been rarely addressed. In this paper, the absolute threshold of cooling (ToC abs) —the specific threshold of a certain influencing factor to ensure the effective cooling of a particular patch type, was proposed and defined for the first time to facilitate the research. The effects of size, shape and neighboring greenspace percentage (NGP) of different types of LULC patches on land surface temperature (LST) were examined and their corresponding ToC abs values were determined if existed, in the metropolitan areas of Beijing, Shanghai and Tianjin using satellite images. Results demonstrate that larger-sized and complex-shaped water bodies and forested areas produce greater cooling effect. The size is irrelevant to the cooling intensity of grass-dominated patches. ToC abs of patch size exist and were identified for water bodies (Beijing, 5 ha; Shanghai, 10 ha; and Tianjin, 5 ha) and forested areas (Beijing, 20 ha; Shanghai, 50 ha; and Tianjin, 20 ha). Besides, NGP is negatively correlated with patch LST for all LULC types, indicating that increasing the amount of neighboring vegetation cover can effectively lower the nearby patch LST. ToC abs of NGP exist and were identified for water bodies (Beijing, 30.3%; Shanghai, 61.6%; and Tianjin, 20%) and grass-dominated areas (Beijing, 89.1%; Shanghai, 76.9%; and Tianjin, 81.5%). Among the three influencing factors, the size accounts for greatest variability in patch LST for forested areas and impervious surfaces, and neighboring greenspace proportion accounts for the most variability in LST for water bodies and grass-dominated areas. The methodology and results of this study could help to orientate specific and actionable landscape strategies of urban cooling. [ABSTRACT FROM AUTHOR]

The increasing free access of the Internet provides us with favorable circumstances to investigate search engine index reflecting more and more personal behavior information. Part of valuable travel search information can assist us to achieve more robust and reliable prediction of metro passenger flow. Inspired by this, the paper develops a new multi-source time series fusion and direct interval prediction approach to grasp the dynamic law of metro passenger flow effectively. Multi-source index regarding metro travel from three major search engines (Baidu, Sogou and 360) in China are screened out and fused into the powerful predictors. By integrating an optimized multivariate mode decomposition strategy and long short-term memory model, lower and upper bounds of prediction interval are estimated directly by a multi-objective framework that combines the advantages of both the deep learning models long short-term memory and the ensemble learning approach. Especially, two sets of real experiment data of Beijing and Shanghai metro systems are employed to test our approach. Findings show that fusion of multi-source index information promotes the predictability of metro passenger flow, contributing to improving operation management and service quality. [Display omitted] • Fusing multi-source search data from three search engines based on query popularity. • Developing a new multivariate preprocessing technique MOHHOMVMD. • Proposing a direct multi-objective interval prediction approach LSTM-based LUBE. • Verifying the superiority of our approach over six benchmark models in two cases. [ABSTRACT FROM AUTHOR]

• Knowledge and technologies produced in Chinese cities has increasingly taken a greater share of total output of global cities. • The quality of this output has increased over time Chinese cities improve the quality of their knowledge output before increasing the quality of technology. • Only Beijing, Shanghai & Shenzhen compete globally in terms of quality of output – other Chinese cities do not. • This can be a mechanism for increasing regional inequality within China. Are Chinese cities becoming smarter in terms of the knowledge and technologies they produce? For decades, the widely held believe in the global North is that China merely copies, imitates and only incrementally improves ideas. Recently, this believe is increasingly being challenged. In this paper I quantify this process. Using data from about 6,1 million patents and 60 million academic publications I examine the complexity of technologies and knowledge developed in major Chinese cities and compare these to those produced in other global cities. The results show that (1) knowledge and technologies produced in Chinese cities has increasingly taken a greater share of total output of global cities; (2) the quality of this output has increased over time; (3) Chinese cities improve the quality of their knowledge output before increasing the quality of technology; and (4) only Beijing, Shanghai and Shenzhen compete with other global cities in terms of the quality of output, suggesting emerging regional inequality within China linked to knowledge and technology production. Not only is the size of the Chinese economy increasing, so is the quantity and quality of its knowledge and technology output. [ABSTRACT FROM AUTHOR]

With the boom of big data, the Internet contains more and more personal behavior information, but it is difficult to extract effectively. A model involving multivariate processing capability must be constructed to deal with these time series with complex characteristics. In this paper, a novel hybrid model embedding Baidu Search Index is therefore proposed to implement multi-step ahead subway passenger flow forecasting. Firstly, we collect data from informative Baidu Search Index, reduce dimensionality, and screen out the powerful predictors by statistical analysis. Secondly, we extract matching common modes at similar time scales between the subway passenger flow and screened Baidu Search Index via multivariate mode decomposition being optimized by multi-objective algorithm. Furthermore, to eliminate pseudo statistical causality, we select the optimal combination of modal components between subway passenger flow and its corresponding Baidu Search Index at each time scale by an innovative multi–modal analysis strategy. Thirdly, we reconstruct the forecasting values of each selected optimal combination as the final results. The empirical results of Beijing, Shanghai and Guangzhou show that the proposed model can significantly outperform six benchmark models in both the level and directional accuracy. So introducing Baidu Search Index creates a sound opportunity to enhance the subway passenger flow forecasting ability. [ABSTRACT FROM AUTHOR]

Abstract: External wall insulation plays an important role in building energy consumption through affecting cooling and heating energy uses. In this paper, a study on the effects of external wall insulation thickness on annual cooling and heating energy uses under different Chinese climates is reported. Firstly, two indexes: Energy Gain Ratio (EGR) and Relative Variation Ratio (RVR) of the sum of annual cooling and heating energy uses, to assess the effects of external wall insulation thickness on energy saving potential are introduced. Secondly, a model space having four different exterior zones facing four different orientations in an office building is presented and the settings of the model space described. Lastly, the simulated annual cooling and heating energy uses for the four different exterior zones at different external wall insulation thicknesses under three different climates in China, Guangzhou, Shanghai and Beijing, are reported. The results suggested that energy saving was significant by increasing the external wall insulation thickness in exterior zones facing all orientations under Beijing’s climate, since the heating energy use was dominant and can be reduced remarkably with the increase in insulation thickness. Under Shanghai’s climate, increasing external wall insulation thickness to over 26mm would not reduce the sum of annual heating and cooling energy uses in the south-facing exterior zone, but would help save energy in exterior zones facing the other three orientations. For all exterior zones under Guangzhou’s climate, it was, however, hardly possible to reduce the sum of annual heating and cooling energy uses by increasing the external wall insulation thickness. [Copyright &y& Elsevier]

Abstract: Indoor environment quality is simultaneously determined by thermal, acoustic, and luminous environments and air quality. This paper reports the findings of field studies conducted in public buildings in Beijing and Shanghai in 2008 and 2009. The studies included measurements of indoor environmental parameters such as air temperature, mean radiant temperature, relative humidity, air velocity, CO2 concentration, illumination intensity, and A-weighted sound pressure levels, as well as investigations of the occupants’ satisfaction with these indoor environments. A predictive model for evaluating overall satisfaction with the indoor environment was developed based on the analysis of the relationship between occupants’ satisfaction and the different environmental parameters. This model can provide a valuable reference for building designers as they compare different schemes by helping them choose designs favored by most people. [Copyright &y& Elsevier]

Abstract: Previous studies have understood urban competitiveness mainly from an economic perspective. Drawing on insights from recent debates on urban governance that argue for sustainable development, this study employs a more balanced view that takes into account the economic, social, and environmental dimensions of urban competitiveness. A four-level hierarchical indicator system is used to examine the competitiveness of 253 Chinese cities at the prefecture level or above in the year 2000. The results show that most of the top 20 cities are in the eastern part of China and have populations over 0.5 million. The bottom 20 cities are located primarily in the western part of China and have smaller populations that range from 0.2 to 0.5 million. In 2000 the city with the top economic competitiveness was Shanghai, the top social competitiveness was Beijing, and the top environmental competitiveness was Zhuhai. A given city does not necessarily rank the same in economic, social, and environmental competitiveness, but may perform well in different ways. The paper argues that, in order to sustain urban competitiveness, a city should achieve not only good economic performance, but also satisfactory social and environmental development. [ABSTRACT FROM AUTHOR]

Abstract: Residential development provides product/service value like floor space, while at the same time it induces severe environmental impacts. This paper introduces a methodology for eco-efficiency (EE) evaluation of residential development at city level, which links product/service value and environmental impacts together. Different from previous researches on environmental impacts related to the construction process of residential buildings, the proposed methodology selects the ecological footprint (EF) as an aggregate environmental indicator to represent all resources consumed and all wastes produced by residential development, while the traditional EF model of a region is improved in view of characters of residential development. Since the final and main objective of the residential development is to provide floor space, which is chosen as the indicator of product/service value herein. The proposed methodology is applied and exemplified in the eco-efficiency evaluation of residential development in three Chinese cities, namely, Beijing, Shanghai, and Nanjing. Results derived from the proposed methodology can help policy-makers and participants in the industry to assess residential development quantitatively and roundly. They can also provide implications for the environmental management of residential development at city level. [Copyright &y& Elsevier]

Multiyear inventories of vehicular emissions in Beijing, Shanghai and Guangzhou from 1995 through 2005 have been developed in this paper to study the vehicle emissions trends in China''s mega cities during the past decade. The results show that the vehicular emissions of CO, HC, NO x and PM10 have begun to slow their growth rates and perhaps even to decline in recent years due to the implementation of measures to control vehicular emissions in these cities. However, vehicular CO2 emissions have substantially increased and still continue to grow due to little fuel economy improvement. Passenger cars and large vehicles (including heavy duty trucks and buses) are the major sources of vehicular CO2 and CO emissions while large vehicles were responsible for nearly 70% and 80% of the vehicular NO x and PM10 emissions in these mega cities. Motorcycles are also important contributors to vehicular emissions in Guangzhou and Shanghai. [Copyright &y& Elsevier]

Agricultural sector is the basic industry supporting the construction and development of national economy. With the continuous deterioration of agricultural pollution, measuring and understanding agricultural total factor productivity (AGTFP) is the important premise to achieve agricultural green development and clean production. Regarding carbon emissions and agricultural non-point source pollution (ANSP) as undesired outputs, this paper applies a three-stage Data Envelopment Analysis (DEA) method combined with the Slack-Based Measure (SBM) model to eliminate the influences of environmental factors and random errors and explore the real AGTFP of 30 provinces in China from 2000 to 2017.On this basis, the spatial distribution and dynamic changes of AGTFP before and after adjustment are further discussed to seek the underlying reasons. The empirical results demonstrate that AGTFP is lower when carbon emissions and ANSP are both considered, and it decreases from east to west in StageⅠbut the Northeast region surpasses the East to achieve the highest productivity after removing the interferences. Moreover, China's AGTFP has been restricted by the external environment, and superior external environment disguises the poor management efficiency of Beijing and Shanghai. Therefore, some policy implications to balance agricultural environment and economic development are proposed. [Display omitted] • Non-point source pollution and CO 2 are integrated to measure agricultural green efficiency. • A three-stage SBM-DEA approach is employed to calculate the real agricultural green total factor productivity. • Different environmental factors have different effects on the slack of agricultural inputs. • China's agricultural green total factor productivity is restricted by the external environment. [ABSTRACT FROM AUTHOR]

• The net CO2 emissions of the Beijing-Shanghai high-speed rail are assessed. • The framework incorporates modal substitution and traffic generation effects. • Avoided infrastructure expansion and vehicle manufacturing are considered. • Large share of traffic diverted from ordinary-speed trains may raise emissions. This paper provides an ex-post assessment of net carbon dioxide (CO2) emissions of the Beijing-Shanghai high-speed rail (HSR) by including both mode substitution and traffic generation effects with a life-cycle approach. We are among the first authors to examine the emissions effects of a long-haul HSR and to consider the effects of avoided infrastructure expansion and vehicle manufacturing due to traffic diversion. We find that avoided infrastructure expansion plays a limited role in offsetting CO2 emissions from the construction of an HSR infrastructure, but the reduced demand for passenger vehicles can offset a larger share of emissions from the manufacturing of HSR rolling stock. Initially, too much traffic was diverted from ordinary-speed rail (OSR) to HSR, increasing emissions at the operation stage. As traffic diverted from road and air increased, the net emissions at the operation stage turned negative, offsetting emissions from infrastructure construction and vehicle manufacturing. [ABSTRACT FROM AUTHOR]

With the continuous advancement of global urbanization and increasingly serious ecological problems, ecological space protection has gradually become one of the concerns of urban planning. Although some cities worldwide have relatively robust urban planning implementation systems, due to the different planning means and methods of ecological space protection, there lacks a set of standards for the evaluation and inspection of ecological spatial planning implementation, and the traditional evaluation method has some obvious shortcomings, such as low efficiency, poor accuracy, and one-sided comparison. Therefore, the content of this paper includes the following. (1) An evaluation framework for the implementation of ecological spatial planning is proposed, and was constructed from the following four dimensions: ecological index control, spatial form evolution, ecological reserve control, and policy implementation. (2) To verify the operability of the framework, the implementations of the ecological spatial planning of Beijing, Shanghai, and Guangzhou, three cities in China characterized by rapid urbanization processes, were analyzed and compared. The results show that Guangzhou has the best implementation performance, followed by Beijing with a small gap, while Shanghai lags behind the former two with a large gap. The proposed evaluation framework provides a multi-dimensional and comprehensive evaluation method for the implementation of ecological spatial planning, as well as a certain reference for the evaluation of rapidly urbanizing areas worldwide. [ABSTRACT FROM AUTHOR]

Abstract: Based on the generic dynamic building energy simulation environment, EnergyPlus, the simulation model of energy recovery ventilator (ERV) is developed in this paper. With different indoor temperature set-points, the energy performance of ERV along with the availability of ERV is investigated both for Beijing and Shanghai weathers in China in terms of the ratio of heat recovery to energy supply by HVAC devices and ERV. Simulation results show that the seasonal average of the ratio is linear with indoor temperature set-points. The availability of ERV in Shanghai is better than that in Beijing during the winter. In summer, the utilization of ERV is uneconomical if the indoor temperature set-point is higher than 24°C for the Beijing climate. The indoor temperature set-points have the reverse effects to the availability of ERV in the mid-season and to that in the hottest months. Meanwhile, the heating amount recovery in summer and the cooling amount recovery in winter, both of which impair the strong points of the energy recovery, are analyzed quantitatively. [Copyright &y& Elsevier]

• A method to solve train rescheduling and passenger reassignment simultaneously. • An integrated optimization model is formulated with a bi-objective function. • Our method can facilitate real-time rescheduling and re-ticketing efficiently. • Non-dominated train rescheduling and passenger reassignment solutions are obtained. During railway operations, unexpected events may influence normal traffic flows. This paper focuses on a train rescheduling problem for handling large disruptions, such as a rolling stock breakdown leading to a cancelled train service, where passenger reassignment strategies have to be considered. A novel mixed-integer linear programming formulation is established with consideration of train retiming, reordering, rerouting, and reservicing (addition of extra stops). The proposed mathematical formulation considers planning extra stops for non-canceled trains in order to transport the disrupted passengers, which were supposed to travel on the canceled train, to their pre-planned destination stations. Other constraints deal with limited seat capacity and track capacity, and mapping train rescheduling with passenger reassignment. A bi-objective function is optimized by a weighted-sum method to maximize the number of disrupted passengers reaching their destination stations and to minimize the weighted total train delay for all non-canceled trains at their destinations. A series of numerical experiments based on a part of the Beijing-Shanghai high-speed railway line is carried out to verify the effectiveness and efficiency of the proposed model and to perform a sensitivity analysis of various performance factors. The results show that an optimal reassignment plan of disrupted passengers is important to achieve real-time efficiency of traffic and re-ticketing. The impact of passenger reassignment on train rescheduling is influenced by the weights for objectives, duration of disruption, allowed additional dwell and running times, and relationship between passenger demand and total available train capacity. [ABSTRACT FROM AUTHOR]

Carbon prices are low and fluctuate greatly since Chinese carbon emissions trading scheme pilots were operated. This paper discusses the price drivers in the pilots, using structural breaks test and autoregressive distributed lag model. The results indicate that oversupply of allowances, low auction prices and use of China certified emission reductions will cause remarkable decline on carbon prices; the expansion of carbon market and centralized trading will rise carbon prices. Oil prices are positively correlated with carbon prices, and coal prices are negatively related with carbon prices. Carbon-intensive product prices also affect carbon prices. Chemical prices are positively linked with carbon prices in Shenzhen, while negatively related with those in Beijing and Shanghai, for differences in sectoral coverage. Nonferrous prices have positive impacts on carbon prices in Beijing but negative impacts on those in Shenzhen, for differences in industrial structure. Financial markets and weather have limited impacts on carbon prices. Our results provide policy implications for the development of pilots and the national carbon market. [ABSTRACT FROM AUTHOR]

Climate change action requires both adaptation and mitigation. Both need urban planning in strategic and statutory processes to mainstream the innovations now appearing. Integrating adaptation and mitigation is demonstrated using two planning tools: water sensitive urban design and biophilic urbanism and both need to be mainstreamed through urban planning in a rapidly warming world. Mitigation must be about grasping the need for decoupling fossil fuel use from GDP and data indicates this is underway. Cities like Shanghai and Beijing are showing how emerging cities can decouple wealth and car use. Disruptive innovations underway are solar and wind power, batteries, and electrifying transport but need planning tools to mainstream them. Emerging disruptive innovations include Trackless Trams that function like light rail but at significantly less cost and Hydrogen in fuel-cell vehicles for heavy transport and as an industrial fuel. The Theory of Urban Fabrics is used to show how emerging innovations can be mainstreamed in urban planning through each of the different fabrics of the city. This is illustrated using the six tools outlined in this paper to demonstrate how such nuanced and integrated urban planning responses to climate change can be mainstreamed. • Adaptation to climate change can be integrated into city and regional planning as illustrated in Perth's water sensitive urban design and Singapore's biophilic urban design. • Mitigation needs cities to demonstrate the decoupling of greenhouse emissions from wealth generation. This requires structural efficiencies that are mainstreamed through urban planning. • Disruptive innovation is also critical to mitigation being achieved rapidly and can now be seen in power and transport through solar, wind, batteries and electric vehicles, with potential disruptive innovations such as Trackless Trams and Hydrogen. • The Theory of Urban Fabrics can enable city planning to mainstream all of the above innovations by focusing different planning strategies in different parts of cities and their regions. [ABSTRACT FROM AUTHOR]

Automatically monitoring newly constructed building areas (NCBAs) is essential for efficient land resource management and sustainable urban development, particularly in the rapidly urbanizing country of China. In this regard, time-series multi-view high-resolution optical satellite images can provide fine spatial details for clearly characterizing NCBAs, but this leads to great heterogeneity and complexity, owing to the high spectral variation, complicated imaging conditions, and different viewing angles. Moreover, to date, the vertical features and time-series information from these images have not been fully exploited for urban change detection. In this paper, our primary objective is to automatically detect the presence of NCBAs, and meanwhile, to investigate the feasibility of identifying their change timing using time-series multi-view ZY-3 high-resolution satellite images. To this aim, we propose an automatic change detection method consisting of three components: 1) firstly, we jointly use planar-vertical features to delineate the NCBAs; 2) object-based temporal correction is subsequently applied to improve the spatiotemporal consistency of the features; and 3) finally, a multi-temporal change detection model is used to simultaneously capture the NCBAs and the change timing. We applied the method on two urban fringe areas of Beijing (7 multi-temporal image sets) and Shanghai (7 multi-temporal image sets), respectively, which are cities that have been experiencing rapid urbanization. The experimental results confirmed the effectiveness of the proposed method. For both study areas, the F-score values reached nearly 90% in terms of NCBA detection, and with respect to the change timing, the overall accuracies with a one-year tolerance strategy reached around 92%. The joint use of the planar-vertical features and the inclusion of multi-temporal images make the proposed method a promising approach for automatically providing the spatiotemporal information of NCBAs in practical applications. • An automatic method for monitoring newly constructed building areas (NCBAs) • Time-series multi-view high-resolution optical satellite images were adopted • Joint use of planar-vertical features for delineating NCBAs • Object-based temporal correction for improving spatiotemporal consistency • Multi-temporal change detection for deriving change location and timing [ABSTRACT FROM AUTHOR]

Renewable energy (RE) is strategically important to achieve sustainability. Its development in China, however, is clearly imbalanced across regions. The uneven distribution of natural resources, financial resources and other factors across this country has brought serious challenges to the policymakers. It is thus important to give a comprehensive evaluation of China's regional RE development. To do so, this paper introduces a multidimensional approach and establishes a quantitative evaluation framework. Based on the existing literature, five dimensions of factors have been chosen for the framwork: economic foundation, institutions, technological development potential, energy security and environmental protection, and current status of the RE sector. A dynamic principal component analysis technique is applied to data from 29 provinces between 2008 and 2014. The results demonstrate large variations in RE development across provinces in China. More economically developed regions, such as Beijing, Shanghai, and Guangdong, have maintained a higher ranking and have clear advantages in almost all dimensions. Policy implications and recommendations for more balanced development across China are drawn from the empirical results. This approach can also be extended to investigate similar issues in other countries. • A five-dimensional index is proposed to quantify renewable energy (RE) development in China. • RE development performance in China has improved over time. • Disparities in RE development across regions have become smaller. • The institutional dimension is a challenging segment in RE development. • Beijing and Shanghai have the highest level of RE development. [ABSTRACT FROM AUTHOR]

The capacity allocation is a practically significant factor to influence the quality of the train timetables in the rail operations, especially under the fluctuation of passenger demands. This paper aims to investigate a detailed description for the structure and characteristics of the capacity allocation problem under random demand in the high-speed rail network. A two-stage stochastic integer programming model is provided to get the capacity allocation solutions to meet random fluctuations of passenger demands in the daily operations, which incorporates demand uncertainty and makes no assumptions for the rail network structure and distribution of passenger demands. Given the inherent complexity for solving this problem, we provide a solution framework including a heuristic algorithm based on tabu search in order to obtain a near-optimal solution and strategies to obtain an efficient timetable and train formation adjustment. Finally, two sets of examples, in which a sample rail network with 5 stations and the Beijing-Shanghai high-speed rail network data are adopted as the experimental environments to illustrate the performance and effectiveness of the proposed methods. • A two-stage stochastic program model for train capacity allocation is presented. • A heuristic algorithm based on tabu search is provided to solve the problem. • A strategy for an efficient timetable and train formation adjustment is provided. • Numerical experiments are given to illustrate the proposed approaches. [ABSTRACT FROM AUTHOR]