Children's daily travel to school in Johannesburg-Soweto,South Africa: geography and school choice in the Birth to Twenty cohort study

This paper has two aims: to explore approaches to the measurement of children's daily travel to school in a context of limited geospatial data availability and to provide data regarding school choice and distance travelled to school in Soweto-Johannesburg, South Africa. The paper makes use of data from the Birth to Twenty cohort study (n?=?1428) to explore three different approaches to estimating school choice and travel to school. First, straight-line distance between home and school is calculated. Second, census geography is used to determine whether a child's home and school fall in the same area. Third, distance data are used to determine whether a child attends the nearest school. Each of these approaches highlights a different aspect of mobility, and all provide valuable data. Overall, primary-school-aged children in Soweto-Johannesburg are shown to be travelling substantial distances to school on a daily basis. Over a third travel more than 3 km one way to school, 60% attend schools outside of the suburb in which they live, and only 18% attend their nearest school. These data provide evidence for high levels of school choice in Johannesburg-Soweto, and that families and children are making substantial investments in pursuit of high-quality educational opportunities. Additionally, these data suggest that two patterns of school choice are evident: one pattern involving travel of substantial distances and requiring a higher level of financial investment and a second pattern involving choice between more local schools, requiring less travel and a more limited financial investment.     

Multi‐Domain User‐Generated Content Based Model to Enrich Road Network Data for Multi‐Criteria Route Planning

By utilizing today's web‐based technologies, people can act as sensors and share their perceptions, emotions and observations in a variety of data forms, such as images, videos, texts, Global Positioning System (GPS) trajectories and maps. These forms are collectively called user‐generated content (UGC). These data are in different domains and have a multi‐modality nature. Although recent efforts have probed the acquisition of local knowledge by using single‐domain UGC data in specific applications, such efforts have not thus far presented a model considering multi‐domain UGC specifically to enrich road network data. This article aims at presenting such a model wherein, with the help of each data domain of UGC, one aspect of people knowledge about the road segment is obtained. These different aspects of knowledge are integrated using a Skyline operator to support multi‐criteria route finding. We name this model ERSBU (enriching road segments based on UGC). In ERSBU, road segments are basic spatial units, and their subjective properties have been extracted by using available UGC. The scenic score for each road segment was computed by using geo‐tagged Panoramio photos. The accessibility level of each road segment to different facilities was calculated based on data captured from Wikimapia and OpenStreetMap. Moreover, for measuring the movement popularity of each road segment, Wikiloc and Everytrail GPS trajectories were utilized. For the implementation of the ERSBU model, Tehran region 6 was considered the case study area. The Evaluation of the results proved that road segments that achieved a high score based on knowledge extracted from UGC also mostly gained top scores by analyzing traditional maps. ERSBU allows users to accomplish more‐qualitative path finding by considering the multi‐view characteristics of road segments.     

城市设施环境对初中学生体质健康的影响——以大连市主城区为例

青少年学生体质下降,身体形态肥胖化。论文以BMI指数衡量学生体质健康,通过地理加权回归模型分析了校内、通学以及社区服务设施对初中学生体质健康的异质性影响。发现:(1)初中学生体质健康社区分异明显,超重低风险和未超重高风险社区围绕超重高风险社区集聚。(2)能量摄入型设施分布从中心向边缘逐渐减少,能量消耗型设施表现出相反的特征,道路网密度向中心集聚,医疗设施呈离散分布。(3)学校人均绿地面积,通学距离、道路网密度,公交站、西餐厅、休憩设施、零售设施、医疗设施可达性对学生体质健康的影响在中心区与边缘区具有异质性。     

URBAN SPRAWL,OBESOGENIC ENVIRONMENT,AND CHILD WEIGHT

Using the 1979 National Longitudinal Survey of Youth along with the child survey, we examine the relationship between urban sprawl of U.S. metro counties and the body mass index (BMI) of children who reside in these counties. We make a distinction between urban sprawl in a county and its geographical placement in the urban hierarchy. Even after accounting for unobserved individual heterogeneity and resulting selection bias, we find that urban sprawl is positively related to child BMI and distance to large metros is negatively related to child BMI. These effects are somewhat pronounced among girls and middle/high school children.     

Australian children's independent mobility levels: secondary analyses of cross-sectional data between 1991 and 2012

This study investigated changes in Australian children's independent mobility levels between1991 and 2012. Data from five cross-sectional studies conducted in 1991, 1993, 2010, 2011 and 2012 were analysed. Parent and child surveys were used to assess parental licences for independent mobility and actual independent mobility behaviour in children aged 8–13 years. Findings show declines in the proportion of young children (≤10 years of age) being allowed to travel home from school alone (1991: 68%, 1993: 50%, 2010: 43%, 2011: 45%, 2012: 31%) and travel on buses alone (1991: 31%, 1993: 15%, 2010: 8%, 2011: 6%, 2012: 9%). Furthermore, the proportion of children travelling independently to school decreased (1991: 61%, 1993: 42%, 2010: 31%, 2011: 32%, 2012: 32%). Significantly fewer girls than boys travelled independently to school at each time point (p?≤?.001). Overall, the findings suggest that Australian children's independent mobility levels declined between 1991 and 2012.     

Where dogs,ghosts and lions roam: learning from mobile ethnographies on the journey from school

This paper draws on mobility research conducted with children in three countries: Ghana, Malawi and South Africa. It has two interlinked aims: to highlight the potential that mobile interviews can offer in research with young people, especially in research contexts where the main focus is on mobility and its impacts, and to contribute empirical evidence regarding the significance of everyday mobility to young people's lives and future life chances in sub-Saharan Africa. During the pilot phase of our research project on children, transport and mobility, the authors undertook walks home from school with teenage children1 We use the terms children and ‘young people’ interchangeably in this paper. When we asked young people aged ca. 12–18 years from the three countries at our Malawi inception workshop about terminology, they expressed no concern about the use of the term ‘child’ for people in their teens. View all notes in four different research sites: three remote rural, one peri-urban. As the children walked (usually over a distance of around 5 km) their stories of home, of school and of the environment in-between, gradually unfolded. The lived experiences narrated during these journeys offer considerable insights into the daily lives, fears and hopes of the young people concerned, and present a range of issues for further research as our study extends into its main phase.     

Choosing Health? Exploring Children's Eating Practices at Home and at School

Abstract:  This paper considers the influences on children's eating habits in both school and home spaces in the UK. Since 2002 the UK government has been committed to halting the increase in child obesity rates, and has sanctioned particular parental and school based practices as more "healthy" than others. This study examines this through critically questioning, in particular, the classed discourses written into health education advice and advocates a new way of thinking about health education messages. Based on qualitative research with children from one secondary school and with eight families in the North of England the paper reveals that while parents and children make decisions about their lives with reference to dominant discourses about ideal "healthy" family eating practices, their ability to realise these practices is limited in numerous ways. Moreover, the influences on children's eating habits in both home and school spaces are intricately interrelated and children's practices are clearly influenced by the spaces they inhabit. Their decisions involve balancing health education knowledge with a range of other knowledges that are bound up in the socio-spatial relations of their everyday lives. A holistic approach to understanding children's eating habits therefore requires a critical understanding of class background, parental influences and contemporary parenting practices as well as the microgeographical relations found in the school dining room.     

Shortest-Path Distances: An Axiomatic Approach

An axiomatic approach to distance is developed which focuses on those concepts of distance related to movement in space. The most fundamental types of such distances generally involve some notion of shortest paths between points, where the relevant concept of path length can be any additive attribute of paths (such as physical miles, hours spent in traveling, or gallons of fuel consumed). In particular, the shortest-path distance between any two points in space is here taken to be the greatest lower bound on all path lengths between these points. This notion of shortest-path distance is shown to be formally equivalent to a quasimetric, i.e., a distance which satisfies only the classical triangularity axiom for metrics. The main analysis of the paper focuses on the question of whether or not such shortest-path distances can actually be realized, i.e., on whether there exist shortest paths in space. The central result is to establish a general set of conditions under which such shortest paths always exist. In addition, a condition for the uniqueness of these paths is also established.     

Poverty,School and Work: Children during the Economic Crisis in Indonesia

The problem of child labour in Indonesia, although generally less prevalent than in other developing countries at a similar stage of development, is significant. As in other countries, this study finds a strong link between the child labour phenomenon and poverty, with the profile of child labour largely mirroring the profile of poverty. Furthermore, poverty is found to be an important determinant of whether children work. However, working does not always completely eliminate a child's opportunity to obtain formal education: children from poor households can still go to school by undertaking part‐time work to pay for their education, implying that banning these children from working may force them to drop out of school instead. Since the phenomenon of child labour is strongly associated with and determined by poverty, the most effective policy for eliminating child labour is through poverty alleviation. Other policies that can foster the rate of reduction in child labour are those which make it easier for children from poor families to access education and increase the opportunity cost of working by improving the quality of education. Such policies will increase the rate of return to education.     

Assembling attachments to homes under bushfire risk

This research, conducted in the Blue Mountains, New South Wales, Australia, explores attachment to the home in the context of bushfire risk. The paper builds on existing research that has focused both on the home and on emplaced and mobile methods therein and seeks to understand the range of human and non‐human attachments. We situate our examination of attachment in the context of a bushfire‐prone suburban area to consider whether attachments to home may be influenced by an external risk. We use a mix of verbal, visual, and sensory methods (walking and image‐led interviews) to examine both verbal and sensorial articulations in place and in the home. We report on a stepwise analysis of place attachments, home, and bushfire risk. First and while interviewing, we moved with the participants inside and outside of their homes to understand how attachment to those sites was constructed and maintained. Second, we considered those encounters as assemblages of attachments to place. Finally, we studied those assemblages of home‐bound attachments in the context of the risk of bushfire in proximate suburbs.     

New Zealand parents' understandings of the intergenerational decline in children's independent outdoor play and active travel

Children's independent mobility and physical activity levels are declining in Western countries. In the past 20 years New Zealand children's active travel (walking and cycling) has dropped on average from 130 to 72 minutes per week, and those travelling by car to school have increased from 31% to 58%. This paper describes parents' understandings of why 9–11-year-old primary school children in suburban Auckland are less likely to walk to school and play unsupervised outdoors than they were as children. Data gathered in focus groups show understandings range from proximate neighbourhood explanations to downstream impacts of a neoliberal policy context.     

Generating Alternative Land‐use Allocation for Mixed Use Areas: Multi‐Objective Optimization Approach

Current research is carried out with an intention to present an optimization approach for the urban land‐use allocation problem by generating Pareto optimum solutions considering two objectives—maximizing compatibility among adjacent space uses of a study area without compromising the area’s total land price and maximizing the price of plot of each individual owner. Considering the non‐linear characteristics of the objective functions, a multi‐objective evolutionary algorithm approach called Non‐Dominated Sorting Genetic Algorithm‐II (NSGA‐II) is applied to obtain Pareto optimal land‐use allocation subject to different set of constraints. The objective functions are tested over a case study area of Dhaka, Bangladesh. The resulting NSGA‐II model produces 24 Pareto optimal solutions of land‐use allocation, allowing tradeoff between maximizing compatibility and land price from one solution to other. This research also expresses the potential of the model to aid the policymakers and city planners of development authorities by providing alternative land‐use plans, and thereby predicting the consequences of any plan before practical application.     

Spatial Filtering for Identifying a Shortest Path Around Obstacles

The shortest path between two locations is crucial for location modeling, spatial analysis, and wayfinding in complex environments. When no transportation system or network exists, continuous space movement adds substantial complexity to identifying a best path as there are increased travel options as well as barriers inhibiting potential movement. To derive the shortest path, various methods have been developed. Recent work has attempted to exploit spatial knowledge and geographic information system functionality, representing significant advantages over existing methods. However, a high density of obstacles increases computational complexity making real‐time solution difficult in some situations. This article presents a spatial filtering method to enhance Euclidean shortest path derivation in complex environments. The new approach offers substantial computational improvement while still guaranteeing an optimal path is found. Application results demonstrate the effectiveness of the approach and its comparative superiority.     

Minimum-Cost Distances in Spatial Analysis

An axiomatic approach to distance is developed which focuses on those behavioral concepts of distance related to movement in space. In particular, spatial movement by behaving units is postulated to involve a choice from among some set of abstract trips in space, and implicitly, to involve the minimization of some relevant notion of trip costs. In this context, the relevant behavioral notion of distance in space is taken to be the minimum-cost distance generated by this choice process. These trip-cost concepts extend the classical notions of paths, path lengths, and shortest paths in metric spaces. Hence many of the analytical results of the paper involve extensions of classical shortest-path distance properties to minimum-cost distances. In addition to these extensions, a characterization theorem is given which specifies the possible functional relationships between trip costs and their associated path lengths. These relationships include most functional forms which are commonly employed in the literature.     

Predictors of Out-of-Home Placement in a Family Preservation Program: Are Welfare Recipients Particularly Vulnerable?

Participants in a statewide family preservation program were classified on the basis of income level and enrollment in public assistance. These variables, along with other economic, parent, and child risk factors, were used to predict the probability of out-of-home placements at the close of this intervention program. Results revealed that neither low income nor receiving public assistance was predictive of having a child removed from the home. Higher levels of child-centered risk and parent-centered risk were the only consistent predictors of placement outcomes. Additional analyses revealed that family characteristics (e.g., history of psychiatric care, prior child placements, and involvement with the legal system) also were typical of families experiencing out-of-home placements. This study challenges the stereotype of low-income or welfare families being at greater risk of having a child removed from their home. Findings are discussed in the context of recent welfare reform initiatives and implications for future family policy research.     

Managing Environmental Impacts of Recreation and Tourism in Rainforests of the Wet Tropics of Queensland World Heritage Area

This paper describes environmental impacts of tourism and recreation activities in the world heritage listed rainforests of northeast Australia and presents management strategies for sustainable visitor use of the protected area. Tropical rainforests are characterised by their low resistance and moderate to high resilience to impacts associated with human visitation. Visitor use in the World Heritage Area is mostly associated with walking tracks, camping areas, day use areas and off‐road vehicle use of old forestry roads and tracks. Adverse environmental impacts range from vegetation trampling, soil compaction, water contamination and soil erosion at the local scale through to spread of weeds, feral animals and soil pathogens along extensive networks of old forestry roads and tracks at the regional scale. Concentration of visitor use is the most desirable management strategy for controlling adverse impacts at most World Heritage Area visitor nodes and sites, and includes methods such as site hardening and shielding to contain impacts. For dispersed visitor activities, such as off‐road vehicle driving and long‐distance walking, application of best practice methods by the tourist industry and recreational users such as removal of mud and soils from vehicle tyres and hiking boots before entering pathogen‐free catchments, together with seasonal closure of roads and tracks, are the preferred management strategies. Retention of canopy cover at camping areas and day use areas, as well as along walking tracks and forestry roads is a simple, yet effective, management strategy for reduction of a range of adverse impacts, including dispersal of weeds and feral animals, edge effects, soil erosion and nutrient loss, road kill and linear barrier effects on rainforest fauna.     

今日大海道——大海道考古探险纪实

大海道是古代丝绸之路上连接吐鲁番和敦煌的最近一条路。因道路险阻 ,近现代各种探险活动很难走完全程。新世纪之初 ,我国大海道考古探险队克服重重困难险阻 ,历时11天 ,成功穿越了大海道。文章较为详细地记述了此次探险考察活动的全过程     

Designing Reliable Center Systems: A Vector Assignment Center Location Problem

The p‐center problem is one of the most important models in location theory. Its objective is to place a fixed number of facilities so that the maximum service distance for all customers is as small as possible. This article develops a reliable p‐center problem that can account for system vulnerability and facility failure. A basic assumption is that located centers can fail with a given probability and a customer will fall back to the closest nonfailing center for service. The proposed model seeks to minimize the expected value of the maximum service distance for a service system. In addition, the proposed model is general and can be used to solve other fault‐tolerant center location problems such as the (p, q)‐center problem using appropriate assignment vectors. I present an integer programming formulation of the model and computational experiments, and then conclude with a summary of findings and point out possible future work.     

Poverty,Emigration And Family: Experiencing Childhood Poverty In Late Nineteenth-Century Manchester

The Manchester and Salford Boys’ and Girls’ Refuge offered a place of sanctuary for destitute children. It expanded rapidly during the late-nineteenth century and established a number of homes that catered for a range of childhood needs. This article focuses on the experience of children admitted to the Refuge and subsequently emigrated from one of its orphan home. It considers the processes of child migration by examining the relationships between the home and the family. The analysis questions middle-class ideas about the parenting of poor families, the economic motives behind emigration, and introduces a number of case studies to evaluate whether emigration achieved its goal of leading children towards a respectable life away from the city.     

A comparison study of children's independent mobility in England and Australia

We compared independent mobility (freedom to move around the neighbourhood – or similar – without adult accompaniment) among English and Australian schoolchildren. Parents reported mobility licences granted to their children (e.g. allowing them to cross main roads alone) and accompaniment on local trips. Children reported travel mode to school. We examined associations between mobility licences and independent school journeys, and accompaniment on local trips. Among 10–12-year-olds, English children had more licences than Australian children. Mobility licences were directly associated with independent school journeys among primary but not among secondary schoolchildren who travelled further; and inversely associated with parental accompaniment to other destinations. Influences on parental restrictions should be examined to promote children's independent mobility.