The rapid development of air transport has increased air traffic flow. Corridors-in-the-sky have become a new technology to support the full development and utilization of airspace resources due to its high-density air traffic flow. The identification of congestion period and congestion segment is the foundation of lanes distribution and the operation of activation and deactivation in corridors-in-the-sky. This paper proposes a method which can design corridors-in-the-sky, and identify air congestion and the influence of air routes traffic flow. Based on heavy traffic air routes, locations of corridors-in-the-sky are determined, and the routes-attendees are determined based on distance constrain. Particularly, fourteen corridors-in-the-sky of China are designed. Through space-time data calculation, space-time map compilation, grid frequency filtering and threshold setting, a congestion period and congestion segment are identified in this paper according to the times of overlap and the frequency of the hottest grids. The influence of heavy traffic air routes is also analyzed through the two indexes of scale value and aggregation value. We have the following findings: the congestion period of corridors-in-the-sky presents the structural characteristics of the multi-peak "wavy" scattered distributions, and the later aggregated distribution of top peaks in the whole day. The congestion segment is presented as the structural features of unbalanced coverage and centralized distribution of crossings. The highly congested corridors-in-the-sky are presented as an italic "N" font frame, which is not fully integrated with centralized small segments. In a spatial and temporal interaction, there are two types of congestion segments, single-period and multi-period overlap, and there are some common congestion periods in different congestion segments of multiple corridors-in-the-sky. The heavy traffic air routes play a decisive role in the congestion of corridors-in-the-sky, and the influence of the two directions on arrival and departure is unbalanced. The congestion identification of air traffic is helpful for the dynamical evaluation of China's airspace resource, which can provide a basis for the distribution of corridors-in-the-sky in the future of China.

In the context of globalization, geopolitical relationships should be considered under the general geo-structure. Traditional geopolitical factors such as security are still the indispensable drivers of global patterns. In this study, social network analysis was used to construct an analysis framework from the perspective of a geo-system. Using this framework, we investigated the holistic and structural characteristics of the geo-economic and geopolitical relationships in Southeast Asian geo-system, quantified the power and reliance degrees of each country in terms of geo-economics and geopolitics (security), and also explored the potential mechanisms of security reliance. The results show that: (1) Since the end of the Cold War, the United States (US) replaced Japan as the country that exerted the strongest geo-economic influence on Southeast Asian countries, and then was supplanted by China. In terms of geopolitics, the United States is the most influential country over Southeast Asia. Although China has taken the second seat since 2005, its geopolitical influence is still far behind that of the US. Overall, from a geo-economic perspective, Southeast Asian countries seem to be more dependent on China than on other countries, while geopolitically (i.e., security) they rely mostly on the US and its traditional allies, including the United Kingdom, France and Germany. There is enough evidence to support the well-known adage that "Southeast Asia relies on China in economy, but on US in security". (2) Differences in national power are the essential drivers of security reliance. The specific direction of security reliance is primarily controlled by the geographic distance between countries. In addition, differences in political geographic traits are also essential factors that shape security reliance.

Europe is one of the important regions of 'the Belt and Road Initiative', playing both a significant role as an economic corridor connecting Asia and as an endpoint. In the context of globalization, the Belt and Road Initiative as a form of regional economic integration is driven by improvements in transportation and information technologies. Regional economic integration also weakens the borders among nation-states. However, low-income developing countries are pushed to a more marginal economic position and are deprived of a political voice as regional economic integration plays out in the current world economy. These trends are also playing a role in the rapid spread of conflicts at the global scale, one manifestation of which is the refugee crisis in Europe. Consequently, it is necessary to address the impacts of the refugee crisis in Europe and eliminate potential risks in the economic corridors under the Belt and Road Initiative. Taking into account the perspective of geography and refugee settlement policies of European countries, this paper analyzed the spatial-temporal patterns and optimized the migration routes and resettlement of the refugees arriving in Europe from 2015 to 2017 by conducting gray relational analysis, a hierarchical analysis and multi-objective programming. According to the spatial and temporal evolution analysis, refugees migrating to Europe mainly landed in 2015. Meanwhile, the number of landed refugees accepted by European countries were extremely polarized and uneven. The results of the gray relational analysis showed that the decision-making of resettlement of refugees was highly related to welfare policies and income level in the country of destination. However, the changes in refugee policy in various countries had an uncertain impact on the decision-making process of refugees, which also affected the spatial pattern of resettlement of refugees. The results of the hierarchical analysis showed that the Nordic and western European countries were more attractive for refugees, while the livability of the eastern and southern European countries was relatively poor. The number of refugees accepted by most European countries did not match with their level of livability. The optimized pattern of multi-objective planning indicated the limitations of European refugee policy and the challenges of the existing migrating patterns in the context of globalization. The optimized results showed that the migration trend of refugees originally stranded in Turkey and Ukraine was to concentrate in western Europe, the migration trend of refugees originally stranded in Greece and Hungary showed a relatively equally dispersed pattern throughout Europe, and the migration trend of refugees originally stranded in Italy was dispersed in a sector-shape. The optimized migration pattern provides suggestions for policy making in relieving the deteriorating security in the region, balancing the allocation of labor and providing a potential market for investment in construction under the Belt and Road Initiative.