Stratified mobility, segregated boundary, and socioeconomic mixing in New York

As complex systems, the spatial structure of urban systems can be analyzed by entropy theory. This paper first calculates the interaction force between cities based on the gravity model, the spatial relationship matrix between cities is constructed using the method of network modeling, and the spatial network modeling of urban system can be calculated. Secondly, the Efficiency Entropy (EE), Quality Entropy (QE), and System Entropy (SE) of urban system network are calculated and analyzed by information entropy. Finally, taking the Huaihe River Basin (HRB) as a case study, model verification and empirical analysis are performed. It is found that the spatio–temporal pattern of the urban system network structure in the basin is uneven: in space, the urban system network in the HRB presents a layer-by-layer spatial distribution centered on the core city of Xuzhou; meanwhile, the overall urban system network in the basin presents an orderly development trend. This study has certain theoretical and practical value for the planning of urban and urban systems and the coordinated development of regions.

The urban road tunnel longitudinal ventilation is a complex non-linear process with the feature of strong time-varying, always affected by a good many uncertain factors, it is difficult to establish a precise mathematical model by using the traditional linear control theory. The paper describes an intelligent model consists of two levels of neural network, the first level is a traffic flow neural network model to predict the traffic flow changes in road tunnel, the result of predicting will be used as an input of the second level neural network which is used to describe an intelligent model of urban road ventilation system, through the different states of predicted traffic flow, to establish an Intelligent Model of Urban Road Tunnel Ventilation System Based on Multi-Level Neural Network. This model was used for ventilation intelligent control under the environment of Wu-chang Yue-ma-chang tunnel. Results of field test indicate that the method can highly improve ventilation conditions.

The gravity model is an interesting adaptation of Newton's law of gravitation, in which the effect of gravity is used to describe the spatial interactions between economic units. The force of interaction is supposed to be positively influenced by the size of the units (the push factor) and negatively by the distance between them (the pull factor). The model is used to estimate the dependence of migration on the GDP, as well as the distance between European countries. Based on the gravity model, the GWP of both (source and host) countries, is expected to be a push factor and the distance is expected to be a pull factor. However, in economic theory, the impact of the GDP of a source country is expected to be negative, the opposite to the gravity model. The goal of the paper is to test which of the two is valid for eight European countries from 2011 to 2014.

As an important supplement to “location space”, “flow space” has become an important trend in urban network research. At present, the theoretical basis and empirical research of urban network structure from the perspective of “flow space” are not completely clear. Based on the urban spatial network structure research system framework, this paper comprehensively studies the urban spatial structure, spatial network pattern and development mode of Liaoning Province in China by using multivariate data flow. The results show that: (1) Cities at all levels in Liaoning Province have different functions and roles in the urban network level, with Shenyang and Dalian as the leading cities, and Anshan and Jinzhou as “transit hubs”; (2) Liaoning Province takes Shenyang-Dalian as its main axis, the Shenyang economic circle with Shenyang as the core and the coastal economic belt with Dalian as the core and Dandong and Yingkou as the two wings intersect to form the urban spatial network pattern; (3) In the future, Liaoning Province should further form the urban development model of “core city-axis-cluster”. Under the trend of globalization, it should carry out in-depth promotion in combination with “Shenyang Modern Metropolitan Circle” “Liaoning Coastal Economic Belt” and “Liaoning Northwest Strategy”, and finally form a balanced, efficient and comprehensive urban network structure.

The spatial pattern and evolution of urban system have been hot research issues in the field of urban research. In this paper, the network analysis method based on the gravity model and the related measurements were used to reveal the properties of the spatial pattern and evolution of the urban system in the HRB (Huaihe River Basin) of China. The findings of this study are as follows: During the period from 2006 to 2014, the economic contact between the HRB cities has been strengthened, but the differences between cities have been expanding. In general, the HRB cities have not yet formed a close network structure, and a trend of economic integration has not been found. This paper expresses the spatial pattern and evolution of urban system in an intuitive way and helps to explain the evolution mechanism of urban system. The method was confirmed by empirical research. Because of the operational and visual expression, this method has broad application prospects in the urban system research.

The optimization goal of urban logistics system is to improve the timeliness and reliability of urban distribution. Due to the complexity and versatility of the urban logistics system, natural disasters, human factors and other emergencies will have an impact on the whole system, and the failure of any link in the system will lead to the collapse of the whole system. Therefore, on the basis of considering the characteristics of multiple varieties and small batch of urban logistics distribution, the reliability optimization study of urban logistics system from the reliability of nodes and lines, which is helpful to establish a deeper and clear reliability optimization model of urban logistics system. The reliability of urban logistics system is closely related to its structure. Before the optimization of urban logistics system, what kind of structured logistics network has higher reliability should be first clarified, and the reliability of logistics system should be optimized on this basis. In addition, unimpeded reliability is a comprehensive index to evaluate the network operation status and reliability. Therefore, in the route planning based on unimpeded reliability, the urban logistics system is optimized to maximize the unimpeded reliability of the urban logistics system. In the efficient urban logistics system, in addition to the reliability and smoothness, but also should consider the economy. Since there is a relatively abstract relationship between reliability and cost, here it proposes the reliability distribution model of urban logistics system based on the generalized cost function. The optimization model of the urban logistics system studied in this chapter is a multi-objective optimization covering reliability, smoothness and economy.

The urban public transport system comprises various networks representing different transportation modes with complex internal connections. The common single-layer complex network cannot fully describe the interior characteristics of the system. Therefore, this paper proposes a multi-layer network modeling method for the urban public transport system, which couples different traffic networks into multi-layer networks. We also proposed a centrality measurement of node transfer and designed an attack strategy called the multi-metric joint. The simulation experiment using the geographic information data of Chengdu urban public transport shows that the modeling method can completely and accurately describe the natural urban public transport system. And the multi-metric joint attack strategy is more effective than the traditional attack strategy, which will cause more severe damage to the network. This paper provides a new perspective and method for multilayer network modeling and vulnerability analysis of urban public transport systems.

How does distance affect foreign direct investment? Subject of this research is to determine important factors for the United Kingdom, when undertaking foreign direct investment (FDI). The UK is therefore estimated as the home country of investment, investing in the form of FDI in multiple host countries. More specifically, this research measures determinants of FDI outward stock from the UK to other OECD countries. This research examines how distance affects foreign direct investment and provides twofold contribution. First: Hofstede culture distance effects on foreign direct investment is measured. Second: Geographical kilometer distance effects on foreign direct investment is measured. Methodology used in this research is based on the gravity model, presenting a model setup designed for international trade. Moreover, the research applies foreign direct investment OECD data, together with data on gross domestic product and population. The equation specification combines the economic variables with measures for geographical distances, and the Hofstede Culture measure. First regression equation estimates FDI as a function of GDP, population and Culture Distance. Second regression equation estimates FDI as a function of GDP, population and Geographical Distance. This regression setup provides a clear opportunity to estimate the difference between impact of cultural and geographical distance, represented in the estimation coefficients of the regressions. The British Empire has evolved and through time developed the British culture. Purpose of this current research is to examine how cultural distance and geographical distance impact foreign direct investment, with foreign direct investment often being an indicator of the long-term commitment of foreign investors. Furthermore, with the purpose of finding how foreign direct investment is impacted by several different cultural factors, we analyze various dimensions of the Hofstede culture. These are the power distance (PDI), individualism (IDV), the masculinity/femininity (MAS), and the uncertainty avoidance (UAI). Conclusion is that, all taken together, the research finds foreign direct investment from the UK going to other OECD countries to be more highly affected by geographical distance than cultural distance. Which is interesting considering Brexit. Potentially, this is because the UK is not so culturally different from its main trading partners in the OECD, which is an interesting subject for future research.

Based on the full analysis of the whole process of intercity travel of urban agglomerations, a super network model of urban agglomeration intercity multi-mode traffic system is constructed. The super network link is divided into travel link, transfer link, boarding link and alighting link, in which the travel link includes the travel link on the urban transportation network and the travel link on the intercity transportation network. Considering the factors of travel time, cost and degree of comfort, the generalized cost function and generalized hyper-path cost function are established for all links. On the basis of this, the stochastic equilibrium assignment model of urban agglomeration intercity multi-modal transportation system is proposed and the corresponding algorithm is designed based on MSA algorithm. Finally, an example is presented to illustrate the proposed method.

Identifying and Prioritizing Factors Affecting the Process of Formation of Rural Second Homes Tourism (Case Study: Rural Complex of Javaherdeh in Ramsar)

Many researchers have constructed various types of spatial interaction models including gravity, intervening-opportunity, electro-static field, multiple regression and entropy maximizing models. Among these models, the authors focused upon the distance parameters αi and βi of the gravity and entropy maximizing models (eqns. 2-4), and attempted to investigate empirically the spatial variation patterns and their causes of the distance parameters of the models in Seoul in comparison with them through the above two models.For the purpose of this study, the 111×111 OD data on daily movement of persons within Seoul were employed by the two models, respectively. The distance parameter αi of each unit zone i in the gravity model was estimated by ordinary least square method and, on the other hand, the distance parameter βi in the entropy maximizing model was iteratively calculated with equation 6 derived by Hyman (1969). The results of this analysis can be summarized as follows:1. The spatial variation patterns of the distance parameters αi and βi (in Figs. 2 and 3) indicate that Seoul can be devided into some distinct radii centering from the central business district. These two distance parameters show the far high values in the northeast radius and the low values in the west where the inner-suburban agricultural areas are existed. The intermediate values are revealed in the southeast radius.2. Figure 4 shows the differences between the standardized values of the distance parameters yielded by the two models. Since zones with the remarkable difference are mainly located along the Han River across Seoul from east to west and around the Mt. Bughan in the north, it is considered that the natural topography should influence upon the spatial autocorrelation element in the distance parameter αi of the gravity model.3. As the result of step-wise regression analysis to pursue the causes of the distance parameters in terms of some spatial socio-economic attributes, the percentage of employed persons in the primary industry and the level of income have effect on the both values of the distance parameters (Table 3 and 4). Only in the case of the gravity model, the percentage of employed persons in the secondary industry is considered as a kind of the cause which effects on the distance parameter αi. Though all of these three causes mentioned above decrease the distance parameter values, the percentage of employed persons of the primary industry is the most effective one.

The paper proposes typology of Russia regions by the key features of urban settlement networks. Applied typologizing method is designed for strategic spatial development and involves size-status parameters of central cities along with the intra-regional urban structure (the population of the regional centres and concentration of urban population at the intra-regional level) as principal criteria. At more specific level subtypes, these indicators are extended by two general characteristics of urban settlement – share of the urban population and urban network density. The approach formally allows to engage the settlement pattern morphology as a condition and factor that, directly or indirectly, differentiate regional development. By comparison of two main and two additional urban settlement parameters, 5 types (metropolitan urban systems (capital cities’ agglomerations), urban systems with 1+ million urban centers, systems with major urban centers, urban systems with large-city centers, undeveloped urban settlement systems) and 13 subtypes of regional urban settlement systems are set. The mostly wide-spread is the large-city type, covering a total of 35 regions. A brief description of the types and subtypes of regional urban settlement systems is provided, summarizing principal challenges and directions of strategic spatial development specified by regional features of urban settlement networks.

In this paper, the vulnerability of urban water supply systems was analyzed to protect the safety of water supply effectively, and a new vulnerability assessment model for urban water supply systems was proposed. Firstly, According to the characteristics of systems, the concept of vulnerability in urban water supply systems was proposed based on the definitions of vulnerability in the other areas. Secondly, the interaction of natural, social, economic and environmental factors was considered comprehensively. Then the physical exposure level and inherent respond sensitivity of water supply systems to resist the threat were analyzed, and the disaster respond capacity of human which accompanied with the water supply systems was also analyzed. On this basis, the vulnerability assessment indicators of urban water supply systems were proposed. Thirdly, according to the cascade characteristics and collaborative mechanism of different subsystems, the transmission mechanism of vulnerability in urban water supply systems was analyzed. Then, the vulnerability assessment model for urban water supply systems was established. Finally, the model was used to analyze and assessment the vulnerability of KGWL processing zone's water supply systems in North China. The results show that the assessment model which proposed in this paper is simple, practical, and could be used to provide decision basis for the security upgrade of urban water supply systems.

Management of game species requires an understanding not just of population abundance, but also the structure of and connections between populations. Like other large-bodied carnivores, the cougar (Puma concolor) exhibits density –dependent dispersal and is capable of long-distance movement; in the absence of barriers to movement, these traits should lead to high connectivity between individuals and a lack of genetic differentiation across areas of continuous habitat. Previous research has suggested that cougar movement may be influenced by landscape variables such as forest cover, elevation, human population density, and highways. I assessed the population structure of cougars (Puma concolor) in Washington and southern British Columbia by examining patterns of genetic variation in 17 microsatellite loci, and the contribution of landscape variables to this genetic variation. I evaluated population structure using genetic clustering algorithms and spatial principal components analysis. I quantified the effect of distance on genetic variation by calculating the correlation between the genetic distance and geographic distance between every pair of individuals, as well as the spatial autocorrelation of genetic distances. To compare the observed pattern of genetic differentiation with that which would arise solely from isolation by distance, I simulated allele frequencies across the study area where the cost to movement between individuals was proportional to the distance between them. I also evaluated the support for evidence of male-biased dispersal in allele frequencies. Bayesian clustering analyses identified four populations in the study area, corresponding to the Olympic Peninsula, Cascade Mountains, northeastern Washington and Blue Mountains; these clusters were supported by patterns of genetic differentiation revealed with spatial PCA. v Although I found a significant relationship between the geographic and genetic distance between individuals, simulated allele frequencies displayed no meaningful spatial pattern of differentiation, suggesting that male dispersal would be adequate within the scale of the study area to prevent genetic isolation from occurring if the only factor to affect dispersal was geographic distance. While cougars are capable of long-distance dispersal movements, dispersal in heterogeneous landscapes may be mediated by the resistance of the landscape to movement. I derived resistance surfaces for forest canopy cover, elevation, human population density and highways based on GIS data and estimated the landscape resistance between pairs of individuals using circuit theory. I quantified the effect of the resistance to movement due to each landscape factor on genetic distance using multiple regression on distance matrices and boosted regression tree analysis. Both models indicated that only forest canopy cover and the geographic distance between individuals had an effect on genetic distance, with forest cover exhibiting the greatest relative influence. The boundaries between the genetic clusters I found largely corresponded with breaks in forest cover, showing agreement between population structure and landscape variable selection. The greater relative influence of forest cover may also explain why a significant relationship was found between geographic and genetic distance, yet geographic distance alone could not explain the observed pattern of allele frequencies. While cougars inhabit unforested areas in other parts of their range, forested corridors appear to be important for maintaining population connectivity in the northwest.

Towards a Robust and Flexible Numerical Framework for Integrated Urban Water System Modeling