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Abstract: With the urban rail transit network in Beijing becoming gradually intensive, the passenger flow organization also develops towards the type of the network mode. This paper analyzes the development trend of the urban rail transit network in Beijing. On the basis of a reasonable classification of emergencies occurred in urban rail transit, this paper puts forward the passenger organization model of rail transit network under emergency conditions, and then set a certain train accident of Beijing Metro Line 1 as an example to illustrate the practical application of the passenger emergency organization mode. [Copyright &y& Elsevier]

Abstract: According to the problem that in what scope can subway engineering influence the prices of peripheral real estate, this paper summarized the problems in similar research presented, and put forward that the influence is taken by factors of person, and the influence can be studied by the probability of choosing subway. Different from other similar research, based on the analysis of the factors which can influence people choose subway or not, this paper constructs the logistic model. Testing the model by using the research data of Beijing, this paper get the list on which we know in what scope can subway engineering influence the surrounding real estate prices by adjusting the logistic model variable X4. Finally, discussed the model applicability and in different cities to application. [Copyright &y& Elsevier]

Abstract: Unconventional incidents bring great influence to human life, of which the most destructive is earthquake. Blood is a special resource for lives, especially in a big earthquake, in which there will be a sudden increase in demand for blood, therefore sufficient and safe blood supply is a huge challenge. In this paper, we propose an emergency blood supply scheduling model. Providing decision support for the scheduling of engineering emergency blood supply. We propose a multi-period location - allocation model, and give the heuristic algorithm based on Lagrangian relaxation. Finally, give an example case study in the context of Beijing. [Copyright &y& Elsevier]

Abstract: This paper aims to discuss innovative plan models for Chinese cities that are currently under rapid development. The study considers Complexity Theories of Cities as the theoretical basis and applies a holistic approach in city planning by recognizing the complex nature of city. It strives to integrate the diverse local structure in social and spatial aspects with the ambition and demand of city''s expansion. Digital sequence simulation is used as an innovative tool to represent local activities, promote interventions and predict possible self-organization process in the future. The study arrives at an open scenario, the feasible prospect. A conclusion is drawn to reflect the process and achievement and propose future works for this research. [Copyright &y& Elsevier]

Abstract: The groundwater heat pump (GWHP) system utilizes groundwater as alternative renewable and clean energy source for space heating and cooling, which is an open-loop system that withdraws water from a production well, passes it through a heat exchanger and discharges the water into an injection well. By utilizing the relatively stable temperature of groundwater, GWHP system can work with a higher coefficient of performance. It is necessary to evaluate the aquifer capacity for the proper design and application of GWHP. In this paper, a numerical method of underground heat transfer, energy balance method and thermal storage method were presented to calculate the load capacity of a unit area of shallow aquifer. The model results indicate that the numerical method, which is based on performance efficiency of groundwater heat pump, reflects the behavior of groundwater pumping and recharging processes, and better than energy balance method and thermal storage method, additionally it has the advantages of energy saving and environmental protect. The capacity is positively related to aquifer thickness. The final results show that it is easy for ground water recharging in alluvial and pluvial fan located at the piedmont, while load capacity is relatively smaller. In contrast, it is difficult for groundwater recharging in south-east plain where a larger load capacity is obtained. [Copyright &y& Elsevier]

Abstract: The use of groundwater for cooling and heating purposes is of interest from both the economical and the ecological perspective. The groundwater heat pump (GWHP) system utilizes groundwater as alternative renewable and clean energy source for space heating and/or cooling, withdraws water from a production well, passes it through a heat exchanger and discharges the water into an injection well. By utilizing the relatively stable temperature of groundwater, GWHP system can achieve a higher coefficient of performance. Due to the utilization of groundwater stored in the aquifer, the assessment of the hydraulic capacity of the aquifer based on numerical groundwater models is always needed for the optimum design and the efficient performance of GWHP. In this paper, numerical methods of underground heat-water transfer, energy balance method and thermal storage method were presented to calculate the capacity of unit area of shallow groundwater aquifer. The model results indicate that the numerical method, which is based on performance efficiency of GWHP, represents the behaviour of groundwater pumping/recharging processes, and serves better than energy balance method and thermal storage method, in addition it has been proven itself that this method has the advantages of energy saving and environmental protection. The calculated capacity is positively related to aquifer thickness. It is found that it is easy for ground water recharge in alluvial and pluvial fan located at the piedmont, while the calculated capacity is relatively smaller compared with that of south-east plain where it is not easy for groundwater recharge. [Copyright &y& Elsevier]

Abstract: Air pollutant emission inventory is an important input parameter for chemical transport models (CTMs). Since great uncertainties exist in the emission inventory, further improvements and refinements are required. In this paper, genetic algorithm (GA), a global search and optimization method, was applied to optimize the emission inventory for the Models-3/Community Multiscale Air Quality (CMAQ) model. An emission optimizing system based on GA was developed and embedded to the CMAQ through the design of several core modules, which implemented the basic functions such as emission adjusting, GA population initializing, CMAQ results evaluating and GA operating. Hypothetical and real-data experiments were respectively performed to examine the validity of GA for emission calibrating. GA showed good performance in both experiments and was always able to find the global minimum. The emission optimizing system was then used to calibrate seasonal PM10 emission inventories of Beijing. Results revealed that PM10 emission in Beijing was underestimated in 2002, an average of 62.74% higher adjustment factor should be imposed on the original emission in target months of different seasons. With the calibrated emission inventories, CMAQ model errors were decreased by 6.46% on average in different seasons. It was concluded that GA was a promising search technique in calibrating emission inputs for CTMs. [ABSTRACT FROM AUTHOR]

Abstract: Previous studies have revealed that statistical methods can be used to analyze land-leasing parcel data. However, the conventional statistical methods used in land analysis have some limitations, especially in cases of limited observational data. In this paper, with the help of geographic information system (GIS) techniques, a partial least squares (PLS) path model is applied to study the relationship between residential land prices and various determinants through a case study of Beijing in China. From a preliminary analysis, four latent variables are selected: accessibility of the workplace center, livability, traffic, and environment facilities. The results show that the observation variables have a strong explanatory power for their corresponding latent variables, and the four latent variables have varying impacts on residential land prices. Of the latent variables, accessibility to the workplace center has the strongest impact on the residential land price. [Copyright &y& Elsevier]