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Railways are a crucial part of the African transport network and have a significant impact on the socio-economy and urban development. Previous studies have mainly considered the impacts of railways in Africa from the perspective of economy, politics, security, and natural environment with few attempts to consider land use. Based on Landsat remote sensing data for the 10 km buffer zone along the Ethiopian section of the Addis Ababa–Djibouti Railway (ADR) in 2013, 2017, and 2021, we studied the land use change (LUC) in the area and explored its influencing factors using the ordinary least square model (OLS) and geographical weighted regression model (GWR). There were six key results. (1) Farmland, forest, grassland, and others (including sandy land and bare land) were the primary types of land use, but from 2013 to 2021, the area of built-up land and farmland increased, whereas the area of forest, grassland, and other land decreased. (2) There was a noticeable pattern in the degree of change in the area of built-up land, farmland, and forest as the buffer distance increased along the railway. This pattern indicated a gradual shift in land use and LUC gradients. (3) The land use structure and its changes in the areas surrounding different stations displayed obvious differences. (4) The construction and operation of the ADR is one of the direct factors affecting landscape change along the railway. (5) The distance from the train station, whether the station provides a passenger service, the population size, and the distance from the central city had a positive effect on the expansion of built-up land surrounding the station. The factor of whether the station provides a freight service had a negative correlation with the expansion of built-up land. Socio-economic factors have gradually replaced railway factors as the main driving force of the expansion of built-up land around the stations. (6) The effect strength of different factors on the expansion of built-up land varied in the areas surrounding different stations.

Based on development data relating to China-Africa International Cooperation Parks (CAICPs) from 2003 to 2018, this study examined the transnational investment network of CAICPs using the social network analysis method. The number of CAICPs is increasing. Textiles and apparel, agricultural and food processing, trade logistics and management, building materials and construction, and electrical machinery and equipment manufacturing are the leading industries chosen by most CAICPs. These parks have promoted the economic and social development of African countries, driving the urbanization of the regions in which the parks are located, and they have also benefited China. The network of CAICPs involves China, African countries, and third-party investors. The network is becoming increasingly complex and has an increasingly high density. However, the key node countries and provincial units remain relatively stable despite changes in the network structure. The center of gravity of the network has shown noticeable deviations and regression, and inter-provincial investment cooperation has also been increasing. China-Africa cooperation drives the evolution of the network. In China, the investment of enterprises in Africa is affected by domestic policy, economic pursuit, and investment security. In Africa, the development of CAICPs is driven by development policies and achievements, and it is influenced by African countries’ business environments.

Industrialization is a key element for economic growth in both developed and undeveloped countries. Due to globalization, the cause-effect between industrialization, economic growth and urbanization are changing. This study investigates the relationship between economic expansion, urbanization, and industrialization in Kenya using a quantitative methodology. Using World Bank economic indicator parameters, it focuses on understanding the complex interrelationships between these factors. Vector Autoregression (VAR) modeling is used to analyze the relationships between GDP, urbanization, and industrialization between 1990 and 2018. The Granger causality test is used to determine the causal linkages between GDP, urbanization, and industrialization. Results show that urbanization is increasing steadily across Kenya, with a high population in central, western, Rift valley, and coastal regions. The availability of agricultural land influences urbanization, with a significant positive relationship between the three parameters. The Granger causality test shows a unidirectional relationship between GDP, urbanization, and industrialization. A minimum of 20% is considered as the benchmark for urbanization to reduce both GDP and industrialization. Unplanned and rapid urbanization, accompanied by ecologically unfavorable industrialization schemes, threatens Kenya's biodiversity. The study provides insight into the interconnection between the three pillars of the economy and the statistical models developed are useful in forecasting future trends.

The concept of synchronizability exponent is proposed to define a quantitative characteristic of switching topology. Meanwhile, the Lyapunov exponent is introduced as a quantitative characteristic of agent dynamics. A quantitative relation that the Lyapunov exponent is less than the synchronizability exponent is presented as a new synchronization condition. This condition describes the relationship between agent dynamics and switching topology, which does not seem to have been explicitly considered so far. Under the new quantitative condition, we design state feedback and output feedback protocols to achieve synchronization of linear multiagent systems. We further show that the output feedback protocols can be constructed by separately designing state feedback protocols and state observers, namely the separation principle holds. [ABSTRACT FROM AUTHOR]

A series of 1-D polymer ternary composites based on poly(styrene-butadiene-styrene) (SBS)/carbon nanotubes (CNTs)/few-layer graphene (FLG) conductive fibers (SCGFs) were prepared viawet-spinning. Employed as ultra-high stretchable and super-sensitive strain sensors, the ternary composite fiber materials’ interaction, percolation behaviors and mechanism were systematically explored. The resultant SCGFs-based strain sensors simultaneously exhibited high sensitivity, superior stretchability (with a gauge factor of 5,467 under 600% deformation) and excellent durability under different test conditions due to excellent flexibility of SBS, the synergistic effect of hybrid conductive nanofibers and the strong π-π interaction. Besides, the conductive networks in SBS matrix were greatly affected by the mass ratio of CNTs and FLG, and thus the piezoresistive performances of the strain sensors could be controlled by changing the content of hybrid conductive fillers. Especially, the SCGFs with 0.30 wt.% CNTs (equal to their percolation threshold 0.30 wt.%) and 2.7 wt.% FLG demonstrated the highest sensitivity owing to the bridge effect of FLG between adjacent CNTs. Whereas, the SCGFs with 1.0 wt.% CNTs (higher than their percolation threshold) and 2.0 wt.% FLG showed the maximum strain detection range (600%) due to the welding connection caused by FLG between the contiguous CNTs. To evaluate the fabricated sensors, the tensile and the cyclic mechanical recovery properties of SCGFs were tested and analyzed. Additionally, a theoretical piezoresistive mechanism of the ternary composite fiber was investigated by the evolution of conductive networks according to tunneling theory. 针对现有导电高分子基应变传感材料无法兼顾传感性、 拉伸性和稳定性的难题, 我们采用石墨烯(FLG) 和碳纳米管(CNT) 为复合导电填料、 以聚(苯乙烯-丁二烯-苯乙烯) (SBS) 为柔性基体, 利用湿法纺丝成形技术制备了基于SBS/CNT/FLG三元复合导电纤维(SCGFs) 应变传感器. 系统研究了不同导电材料的含量与比例、 应变幅度与速率等条件下材料传感性能的变化. 结果显示: SCGFs基应变传感器兼 具高灵敏性(GF>5000)、 宽应变范围(> 600 %)与循环稳定性(>200 cycles), 同时可通过改变CNT和FLG添加量实现材料传感性能的精确调控, 这主要归因于SBS良好的拉伸-回复性能、 材料之间较强的π-π相互作用以及复合填料的协同效应. 此外, 我们通过分析拉伸-释放循环实验中SCGFs复合导电纤维导电网络的演变验证了其应变传感机理符合隧道效应理论模型.

Development zones have been an important spatial approach to promoting economic development since China’s reform and opening-up. They have also been major contributors to the processes of China’s industrialization and urbanization. Along with improvements in the worldwide industrial division of labor and the gradual implementation of China’s development zones’ Go Globalstrategy, it is necessary for Africa, a hot spot of global industrialization in recent years, to learn from China’s development zone model. By attracting China’s capital, technology and enterprises to Africa via Sino-African co-built development zones, a pattern of high complementarity and mutual development between China and Africa can be formed which does favor further improvement of the global industrial division of labor. In order to study the applicability and prospect of China’s development zone model in Africa as per the above-mentioned international situation, this paper first sorts out the development course of China’s development zones and discusses their roles in China’s industrialization and urbanization. Subsequently, this paper analyzes the status quo of industrial development in Africa as a whole and the differences in industrial development between China and Africa, aiming to justify the timing of industrial transfer from China to Africa by constructing Sino-African co-built development zones. Lastly, this paper analyzes the current situation of six Sino-African co-built development zones by focusing on their operation modes, industry types and investment promotion models. In the authors’ view, Sino-African co-built development zones can function as a new window of China-African cooperation, a new carrier of African industrialization, and a new engine of global industrial restructuring. China should adhere to the general principles of ‘Sino-African Integration, Multi-Cooperation, Mutual Benefit, Scientific Location, Systematic Planning, Cluster Growth and Open Development’ in the planning and construction of development zones in Africa, effectively promoting Africa as the very important part of the global industry system.

The literature on the development of industrial parks has often been neglected by the role of sustainability criteria for long-term prediction. The current study aimed to evaluate the relationship between industrial park development and sustainability levels in Iran and Turkey from 1980 to 2019. Although many researchers have investigated the link between them in different geographical locations, there is no clear picture of the relationship as the results overall are contradictory. An autoregressive distributed lag (ARDL) model bounds testing panel data method with structural fractures was used to analyze the annual selected data to determine whether the development of industrial parks in Iran and Turkey has been successful. The ARDL model is special in that it incorporates sustainability criteria by role of industrial “parks”. The reasoning behind including this explanatory variable is to determine whether countries with industrial parks are more sustainable and to identify future development challenges. Theory suggests that developing industrial parks will eventually strengthen sustainability regulations and policy implementations based on environmental and economic issues.

Urban fringe area is the most important space for city development. It includes several complicated elements, such as population, space, and management organization. On the basis of local population attributes in the city fringe area combined with people’s movement characteristics in time and space, this article reclassifies basic public service facilities and discusses the relationship between facility layout and housing, employment, and commuter transportation. Through a questionnaire survey in Qiaobei District of the urban fringe area in Nanjing and on the basis of comparative analysis, we discuss the impact factor on the choice of housing, urban services, and the tolerance of commuting time. Our findings indicate mutual promoting and restricting connections among living, employment, and services. Workers’ living situation determines their daily behavior, such as dining, shopping, and entertainment. Furthermore, different income levels have a great influence on residents’ choices with regard to places to live and develop their careers.

In this note, we consider the synchronization problem for discrete-time linear multi-agent systems with time-varying network topology. To describe a new joint connectivity condition for synchronization, the concept of synchronization reachable topology is introduced. Under the conditions that agent dynamics is neutrally stable and network topology is synchronization reachable, a synchronization and an exponential synchronization result are obtained using paracontraction theory. The two results generalize in a natural way the classical results for the consensus of first-order discrete-time multi-agent systems. Finally, the effectiveness of the results is illustrated by a simulation example. [ABSTRACT FROM AUTHOR]

The main prevention and control area for wind-blown sand hazards in northern China is about 320000 km2in size and includes sandlands to the east of the Helan Mountain and sandy deserts and desert-steppe transitional regions to the west of the Helan Mountain. Vegetation recovery and restoration is an important and effective approach for constraining wind-blown sand hazards in these areas. After more than 50 years of long-term ecological studies in the Shapotou region of the Tengger Desert, we found that revegetation changed the hydrological processes of the original sand dune system through the utilization and space-time redistribution of soil water. The spatiotemporal dynamics of soil water was significantly related to the dynamics of the replanted vegetation for a given regional precipitation condition. The long-term changes in hydrological processes in desert areas also drive replanted vegetation succession. The soil water carrying capacity of vegetation and the model for sand fixation by revegetation in aeolian desert areas where precipitation levels are less than 200 mm are also discussed.

In recent years, the Chinese government has changed the one-child policy that was implemented more than 3 decades ago and has began encouraging couples to have 2 children. However, this cannot quickly change people’s reproductive concepts after more than 30 years of low fertility rate and birth control. In this context, the aim of our study was to assess the effect of neighborhood environment on Chinese women’s fertility-willingness for a second child. Our results show that there is a statistically significant relationship between neighborhood environment and women’s fertility-willingness for a second child. Women living in affluent neighborhoods with better living environments have lower fertility-willingness for a second child than those in poor neighborhoods. However, childcare institutions (such as kindergartens) provide shared childcare and improve women’s fertility-willingness. We suggest that to encourage more couples to have a second child, it is necessary to increase the number of neighborhood kindergartens. In addition, local governments must improve the social welfare of migrant households and loosen the requirements for migrant households to obtain local hukou, which will allow migrant children to enjoy local public services, especially education services.

This study analyzed the health of migrants in 4 types of neighborhood in the city of Guangzhou in China. The research shows that the health of internal migrants in urban villages and private housing neighborhoods is much better than those living in older inner city neighborhoods (which are known as jiefang shequ) and unit neighborhoods (which are known as danwei). The reasons behind this are the facts that the migrants in urban villages tend to be relatively young and there tend to be better social and economic conditions in the private housing neighborhood. Moreover, among the 4 kinds of neighborhood, the gap between psychological health and physical health is the largest in urban villages. In addition, migrants who are younger, have better working conditions, and have higher levels of education have better health scores, and they tend to have more friends in the city, larger houses, better insurance, and more satisfaction with their neighborhood relationships, and they tend to be better adapted to urban life. As for the determinants of health, individual characteristics, community factors, and insurance are the most important factors. Specifically, individual age and age of housing have negative influences on physical health while insurance has a positive effect. This study shows that the type of neighborhood that migrants live in has a great impact on their psychological health, which can be improved by promoting neighborhood environments. Last, we propose that it is necessary to implement different strategies in different communities.