Geographies on the Move: A Practical and Theoretical Approach to the Mobile Interview

This article considers the mobile interview method's utility to geography through five strengths: the ability to (1) produce spatially grounded and place-specific data, (2) access subtler and more complex meanings of place, (3) create opportunities for flexible and collaborative conversation with participants in situ, (4) build rapport and adjust participant–researcher power dynamics, and (5) efficiently produce rich geographic data. Practical, technical, ethical, and epistemological considerations are discussed. We expand methodological exploration of disempowered individuals' experiences of home, neighborhood, and urban space. The mobile interview offers a valuable, underutilized method for geographers to better understand the coconstitutive relationship between self and place.     

大数据时代城市时空间行为研究方法

信息技术的快速发展带来了“大数据”时代的到来,改变了城市的空间组织和居民行为,并使得城市时空间行为研究方法面临变革。本文在总结传统城市时空间行为研究方法存在问题的基础上,对影响其变革的数据获取与处理技术进行梳理,重点从居民时空行为、城市空间及城市等级体系3个方面综述了国内外应用大数据进行城市时空间行为研究的最新进展,构建了基于大数据应用的城市时空间行为研究方法框架。本文认为,大数据时代城市时空间行为研究方法的变革主要取决于对反映居民时空行为的网络或移动信息设备数据的挖掘、处理及应用,但是还需要进一步推动相关学科间的交叉与融合,加强社交网站等网络数据在居民时空行为和城市空间研究中的应用,并指导城市规划编制与管理方法的创新。     

The Mobile Street Food Service Practice in the Urban Economy of Kumba, Cameroon

The mobile food service practice is one of multiple survival strategies adopted by poor urban households in Cameroon to maintain and expand the base of subsistence incomes, especially in the current surge of economic crisis. Though a fast-growing informal sector enterprise, it is still at an artisanal stage in urban Cameroon, creating an urgent need for a supportive policy environment that could have measurable positive impacts on improving the productivity, welfare and income levels of the micro-entrepreneurs. This study looks at the mobile food service practice in Kumba, Cameroon, in terms of its basic characteristics, the locational factors influencing its socio-spatial distribution, the critical success factors (CSFs) determining customer choices, and its impacts on the local environmental resources and quality of urban life. The mobile food service practice creates employment, generates income, and acts as a food energy-support instrument to the urban poor and local economic activities operating in Kumba. The vendors, who are mostly women, can make incomes that are 405 per cent of the national minimum wage and, thus, contribute financially towards the education, health and survival of their families. The paper provides some recommendations on ways to improve the efficiency of this sector so as to achieve sustainable economic and social development and to enhance empowerment thereof.     

Co-Mingling Geographic Education with Social Studies Methods

Abstract

Most preservice teachers complete their social science course requirements in isolation from their social studies methods course. This paper reports the unique co-mingling of one interdisciplinary social science course (emphasizing geographic and environmental education) with the social studies methods for a cohort of undergraduate preservice teachers. Integrating parts of their curricula, instruction, assignments, and assessments through a co-mentoring process and action research project connected professors and preservice teachers with children and their environments. A review of the professors' process accompanied by a summary of preservice teachers' projects and reactions describes the classroom experiences and pedagogical outcomes experienced by each group.     

古尔班通古特沙漠沙垄表面的稳定性与顶部流动带的形成

古尔班通古特沙漠是我国惟一受西风气流控制的沙漠,也是我国最大的固定与半固定沙漠。个体沙垄表面的稳定程度从基部至顶部呈现明显的差异。通过分析沙丘的粒度组成、水分动态、土壤植被及生物结皮等下垫面因素的垂直变化,特别是对沙丘表面蚀积过程的实地观测和研究,探讨古尔班通古特沙漠固定、半固定沙垄表面的稳定性和顶部流动带的形成。     

地域主体功能区划理论与方法的初步研究

在对地域主体功能区划的理论依据与原则等进行深入分析的基础上,提出通过生态敏感性等级分区与经济社会发展综合潜力等级分区的空间叠置与地域聚类分析,进行地域主体功能区划的理论方法。并以江苏省新沂市为案例,进行地域主体功能区划实证研究,验证了所提出的地域主体功能区划理论方法的可行性。     

工艺和生产方式(PPMs)对国际贸易的影响和对策

WTO成员方是否能以保护环境为由,对通过污染型工艺和方式生产的产品在进口时采取限制或禁止措施,这是国际贸易与环境领域关注的焦点.本文对工艺和生产方式相关的概念、边境贸易措施、WTO/GATT规则及其发展趋势等作了深入研究和探讨,分析了PPMs措施扩大应用的可能性及对发展中国家的影响,并提出了应对措施建议.     

预处理方法对重庆地区考古遗址粒度分析结果的影响

选取重庆石牛寺和大石洞考古遗址剖面,对比不同预处理方法对粒度测试结果的影响。研究表明：1)加蒸馏水浸泡或0.05 mol/L的(NaPO₃)₆分散剂,并用超声波震荡,分散效果均不明显,主要粒度参数与无预处理实验结果接近,表明物理性预处理方法既不能去除碳酸盐、有机质等杂质,也不能使样品中潜在的胶结团粒分散开。2)加H₂O₂可有效除去地层样品中的有机碎屑物,达到提纯无机颗粒物的目的。该方法预处理后,石牛寺考古遗址沉积物平均中值粒径最小,黏土体积分数最高,相比无预处理测试结果,砂体积分数降低50%左右,且在整个剖面中表现非常稳定;但对于大石洞遗址某些碳酸盐胶结物含量丰富的样品而言,该预处理方法作用有限。3)加10%稀HCl预处理后,石牛寺遗址样品中值粒径有所增大,砂体积分数基本持平,黏土体积分数显著降低,大石洞遗址黏土和砂体积分数同步减少,揭示黏土矿物可能在酸性环境下发生絮凝,从而导致体积分数减少。4)对于碳酸盐胶结物含量较低的环境考古样品,只需加H₂O₂除去有...     

The forward problem of electromagnetic induction: accurate finite-difference approximations for two-dimensional discrete boundaries with arbitrary geometry

We describe finite-difference approximations to the equations of 2-D electromagnetic induction that permit discrete boundaries to have arbitrary geometrical relationships to the nodes. This allows finite-difference modelling with the flexibility normally ascribed to finite-element modelling. Accuracy is demonstrated by comparison with finite-element computations. We also show that related approximations lead to substantially improved accuracy in regions of steep, but not discontinuous, conductivity gradient.