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1.
ABSTRACT

Ciudad Juarez, Mexico, suffered an explosion of criminal violence between 2008 and 2012 that cost the lives of more than ten thousand people, earning it notoriety as the world’s “murder capital.” Just a few years later, however, levels of violence had dropped back to pre-2008 levels, decreasing by more than 85 percent. Existing political, economic, and sociological theories provide compelling narratives about the origins of Mexico’s drug-related violence, but have much more difficulty explaining why violence might suddenly decrease to normal levels again. They also fail to explain how violence itself shapes mechanisms of formal and informal order, often leaving institutional legacies that can be both negative and positive. Based on research conducted since 2008, this paper argues that criminal violence in Ciudad Juarez, while initially begetting only more violence, gradually reconstituted the criminal order in such a way that peaceful interaction among competing criminal groups became possible.  相似文献   

2.
ABSTRACT

The temporal nature of humans interaction with Points of Interest (POIs) in cities can differ depending on place type and regional location. Times when many people are likely to visit restaurants (place type) in Italy, may differ from times when many people are likely to visit restaurants in Lebanon (i.e. regional differences). Geosocial data are a powerful resource to model these temporal differences in cities, as traditional methods used to study cross-cultural differences do not scale to a global level. As cities continue to grow in population and economic development, research identifying the social and geophysical (e.g., climate) factors that influence city function remains important and incomplete. In this work, we take a quantitative approach, applying dynamic time warping and hierarchical clustering on temporal signatures to model geosocial temporal patterns for Retail and Restaurant Facebook POIs hours of operation for more than 100 cities in 90 countries around the world. Results show cities’ temporal patterns cluster to reflect the cultural region they represent. Furthermore, temporal patterns are influenced by a mix of social and geophysical factors. Trends in the data suggest social factors influence unique drops in temporal signatures, and geophysical factors influence when daily temporal patterns start and finish.  相似文献   

3.
《The Journal of geography》2012,111(3):117-120
Abstract

The Threatening Rock mass wasting event at Chaco Canyon, New Mexico, in 1941 introduces students to a well-documented geomorphology case study. Based on data from Schumm and Chorley (1964), students examine the event using rock movement measurements and weather data, undertaking the same analysis tasks as the original investigators. Students observe patterns of movement related to precipitation and temperature, and use regression to estimate the time of initial movement. Specific exercise questions guide students to logical conclusions regarding geomorphic processes and environmental influences. The exercise exemplifies geomorphic investigation from both a process and historic perspective.  相似文献   

4.
《The Journal of geography》2012,111(4):176-178
Abstract

Hilltop Geography is a year-long integrated geography program that involves first and second graders in a hands-on laboratory approach to exploring their immediate environment while at the same time providing a stepping stone to their understanding of the world. This article will describe how teachers and students in a rural New Mexico school have been utilizing the semi-arid hills surrounding their building as an outdoor geography learning laboratory, involving parents and the local community in the process.  相似文献   

5.
Abstract

This paper presents an argument for introducing location-allocation theory to advanced undergraduate and beginning graduate students in a simplified continuous space environment that is relatively free of the distorting effects of networks and other aspects of more differentiated “real-world” environments. This approach can enable instructors to reinforce visually the role of different models and their objective functions. In this simplified setting, students can initially concentrate on the link between these mathematical programming techniques and the spatial nature of the problems being solved. In a short time, students can move into more advanced methods in more differentiated environments. A freeware program entitled NEWLAP was developed to facilitate this approach. This software features a variety of spatial allocation models and their associated constraints that can be applied on both the plane and the sphere. This paper outlines how this software can be used to show alternative solutions using different models on the same data set as well as application of the software in a “real world” problem on a global scale.  相似文献   

6.
Abstract

Models can greatly assist the student to understand important aspects of a complex reality. A simple model, based on empirical data about farm size in Tokugawa, Japan, is here introduced and applied to China. The model makes explicit one of the major lessons East Asian civilization has for regions of the world more recently integrated into “civilization”; that is, that the productive capacity of land, and thus its ability to support people, is finite. The model also provides a useful integrative framework for introduction to the physical aspects of the geography of East Asia.  相似文献   

7.
Abstract

The intermediate disturbance hypothesis (IDH) predicts highest species diversity in environments experiencing intermediate intensity disturbance, after an intermediate timespan. Because many landscapes comprise mosaics with complex disturbance histories, the theory implies that each patch in those mosaics should have a distinct level of diversity reflecting the magnitude of disturbance and the time since it occurred. We model changing patterns of species richness across a landscape experiencing varied scenarios of simulated disturbance in order to predict first the variation of richness through time in individual patches, based on their disturbance histories, and then the changing patterns of richness across the landscape through time, representing the cumulative impact of changing richness within the individual patches. Model outputs show that individual landscape patches have highly variable species richness through time, with the trajectory reflecting the timing, intensity and sequence of disturbances. When the results are mapped across the landscape, the resulting temporal and spatial complexity reveals a distribution of biodiversity that is strikingly contingent on the details of disturbance history. These results illustrate the danger of generalization (in either data interpretation or management decisions), as IDH actually imposes a highly variable pattern of diversity.  相似文献   

8.
《The Journal of geography》2012,111(4):180-186
Abstract

The Geographer at Work by Peter Gould Boston: Routledge &; Kegan Paul, 1985. x and 351 pp., figs., photos, maps, and index. $39.95 cloth; $16.95 paper.

Recollections of a Revolution: Geography as Spatial Science by Mark Billinge, Derek Gregory and Ron Martin, eds. New York: St. Martin's Press, 1984. viii and 235 pp., figs., tables, refs., and index. $25.00 cloth.

The Role of Place in Literature by Leonard Lutwack Syracuse, NY: Syracuse University Press, 1984. viii and 274 pp., refs., and index. $24.95 cloth.

The Essential Landscape: The New Mexico Photographic Survey with Essays by J.B. Jackson. by Steven A. Yates, ed. New Mexico: The University of New Mexico Press, 1985. vii and 147 pp., and photos. $45.00 cloth.

Latin America: Case Studies by Richard G. Boehm and Sent Visser, eds. NCGE Pacesetter Series. Dubuque, IA: Kendall/Hunt, 1984. x and 300 pp., figs., tables, photos, maps, apps., refs., and index. $24.95 paper.  相似文献   

9.

Trends in location, labor force, and procurement practices in maquiladoras are examined using recent data sources. A growing proportion of maquiladoras are selecting interior locations, south of the borderlands. Once dominated by young women, the labor force is rapidly approaching gender parity. While far below prevailing rates in the United States, maquiladora wages are comparable with equivalent manufacturing sectors in Mexico. Majority ownership of maquiladoras is split almost evenly between Mexico and the U.S., however, maquiladoras have failed to develop domestic sources of materials and parts and remain dependent on imported material inputs. As the North American Free Trade Agreement is phased in, the regulatory environment of maquiladoras will change but their role as low cost assembly specialists will persist.  相似文献   

10.
In the last several decades, garbage strikes have taken place around the world. In this article, I examine the case of garbage strikes in Oaxaca, Mexico, a rapidly growing city. Here, garbage, which is normally considered a hazard, is revealed also to be an effective political tool for people demanding “rights to the city.” Processes of modernization that have produced an expectation of cleanliness in modern cities have, at the same time, relied on production and consumption patterns that create more and more garbage. It is this inherent contradiction that provides a space for marginalized people to use garbage as a political tool.  相似文献   

11.
Stephanodiscus niagarae is frequently reported from late Pleistocene (>10,000 yr BP) sediments in central Mexico, with lower abundances through the Holocene. Its presence in Holocene and modern environments in central Mexico was not well documented until our study, where we report on three populations of S. niagarae, one middle Holocene population with particularly high abundance from the Upper Lerma Basin, and two modern sites, Valle de Bravo and Santa Elena. The three sites are located in the same geographical area, in the State of Mexico. The fossil material dates to ca. 6600–4900 yr BP, with S. niagarae reaching up to 90% of the diatom counts. Stephanodiscus niagarae is present in association with Fragilaria pinnata, F. brevistriata, and Aulacoseira granulata. In Valle de Bravo (ca. 30 m deep) S. niagarae is present in very low numbers in water column and surface sediments samples (<1%); the diatom assemblage is dominated by Fragilaria crotonensis in association with A. granulata, A. granulata var. curvata and Cyclotella ocellata. In Santa Elena, a shallow, intermittent irrigation channel, S. niagarae is the second most abundant alga; the diatom assemblage is dominated by S. niagarae in association with A. granulata, A. granulata var. curvata and F. crotonensis. Both modern sites show a trend to eutrophy and these diatom assemblages are taken as indicative of this trend. It is suggested researchers should be cautions when the presence of S. niagarae in sedimentary records is taken as indicative of deep waters conditions, as the present data show that this species can thrive in rather shallow environments in Mexico.  相似文献   

12.

In this paper we summarize five experiments that were designed to investigate how tactile maps contribute to the cognitive maps of people with visual impairments. In two experiments we demonstrated that tactile maps can contribute to peoples' ability to learn a route through an unfamiliar area. From the results of two further studies, we argue that compared to people with sight, people with visual impairments have greater difficulty encoding information from a map. We considered this directly in a fifth experiment by investigating how people with visual impairments search and learn a map. We found that they used less efficient strategies than people with sight. We conclude that tactile maps are an important source of geographical information when people need to learn about new environments, but we also point out that to benefit most from tactile maps people need to encode the map information as effectively as possible. As people with visual impairments do not always use the most appropriate encoding strategies we suggest that tactile map users might benefit from greater experience and training in map encoding strategies.  相似文献   

13.
ABSTRACT

Despite much attention paid to the topic of community in academic literature and policy documents, there is a relative lack of knowledge about what laypersons perceive as a local community. Based on data from a national survey, the authors examine how c.1400 Norwegians conceptualized local community – lokalsamfunn in Norwegian. They reveal some of the linguistic and conceptual aspects of local community as a term, in addition to tendencies and patterns among the survey responses. The respondents’ conceptualizations contained references to lokalsamfunn variously as a geographical area, people and relations, activities and involvement, attachment to place and people, and provider of local goods and services. Their main emphasis was on lokalsamfunn as a spatial unit. However, the responses contained relatively few references to the relational aspects of lokalsamfunn. The authors conclude that a common, lay understanding may be that lokalsamfunn is a vaguely defined but limited geographical unit filled with people who to varying degrees know each other and interact. Concerning policymaking aimed at fostering communal well-being, the authors hold that any community-based programming requires intricate knowledge of the people who form the community, since without community interaction and a degree of social cohesion any envisioned programmes may not succeed.  相似文献   

14.
Abstract

Passage of the 26th Amendment gave young adults the right to vote. Along with this privilege, new voters assumed responsibility for conducting themselves as knowledgeable citizens concerning issues, candidates, and the electoral process. This study attempts to further student understanding of the electoral process by presenting a method for analyzing spatial voting patterns. The spatial emphasis adds another dimension to the temporal and behavioral - structural approaches in studying the American electoral system. Inclusion of spatial analysis of voting patterns increases understanding and political socialization of young people.  相似文献   

15.

In Latin America, high levels of crime have prompted many politicians to embrace zero tolerance policing in order to quell public fears. While the overall impacts on urban crime are debatable, zero tolerance in the region has morphed into a powerful policy narrative that symbolizes strong leaders who crack down crime and disorder. Its impacts have been far-reaching; to date, it has been implemented in various guises in Mexico, Brazil, Ecuador, Venezuela, Chile, Argentina, Honduras, El Salvador, Guatemala and the Dominican Republic. Yet, the policy transfer of zero tolerance to Latin America has mutated into a much more punitive approach. In this paper, I develop a critical analysis of the punitive inequalities of zero tolerance policing in Latin American cities, and the consequences for marginalized and racialized youth. I also explore the emergence of a new, unexpected consequence of zero tolerance: the South-North migration of undocumented people.  相似文献   

16.

Ten years after the human immuno-deficiency virus (HIV) was first reported in Ghana, it continues to spread throughout the country following patterns that are rare in other African countries. HIV is seen in twice as many females as males, more frequently in rural than urban regions, and regions with high rates of polygamy have significantly lower rates. The evidence presented in this paper shows that HIV diffusion patterns probably reflect the spatial distribution and social networks of vulnerable social groups. While information-based campaigns are still necessary in the fight against HIV/AIDS, they fail to enable or empower vulnerable people to protect themselves against infection.  相似文献   

17.
ABSTRACT

Social networks have played a crucial role as information channels for people to understanding their daily lives beyond merely being communication tools. In particular, coupling social networks with geographic location has boosted the worth of social media to not only enable comprehension of the effects of natural phenomena such as global warming and disasters, but also the social patterns of human societies. However, the high rate of social data generation and the large amounts of noisy data makes it difficult to directly apply social media to decision-making processes. This article proposes a new system of analyzing the spatio-temporal patterns of social phenomena in real time and the discovery of local topics based on their latent spatio-temporal relationships. We will first describe a model that represents the local patterns of populations of geo-tagged social media. We will then define a local topic whose keywords share a region in space and time and present a system implementation based on existing open source technologies. We evaluated the model of local topics with several ways of visualization in experiments and demonstrated a certain social pattern from a dataset of daily Twitter streams. The results obtained from experiments revealed certain keywords had a strong spatio-temporal proximity even though they did not occur in the same message.  相似文献   

18.
In recent years, the evolution and improvement of LiDAR (Light Detection and Ranging) hardware has increased the quality and quantity of the gathered data, making the storage, processing and management thereof particularly challenging. In this work we present a novel, multi-resolution, out-of-core technique, used for web-based visualization and implemented through a non-redundant, data point organization method, which we call Hierarchically Layered Tiles (HLT), and a tree-like structure called Tile Grid Partitioning Tree (TGPT). The design of these elements is mainly focused on attaining very low levels of memory consumption, disk storage usage and network traffic on both, client and server-side, while delivering high-performance interactive visualization of massive LiDAR point clouds (up to 28 billion points) on multiplatform environments (mobile devices or desktop computers). HLT and TGPT were incorporated and tested in ViLMA (Visualization for LiDAR data using a Multi-resolution Approach), our own web-based visualization software specially designed to work with massive LiDAR point clouds.  相似文献   

19.
Regions and western europe   总被引：1，自引：1，他引：0  
《The Journal of geography》2012,111(1):306-316
Abstract

Regional geography is undergoing important changes in its method of study in order to achieve a greater degree of relevancy in the context of a dynamic global system. Effective knowledge of regional identities can no longer be confined to facts that establish patterns, it also demands a critical appreciation of processes and spatial interrelationships. Western Europe is taken as a case study to reflect this new approach to regional geography, Despite the complexity of this major world region, two basic models are proposed as a basis on which to develop detailed study. Essential patterns of Western Europe are established through six generalizations: location; quality of the environment; industrialization; urban development and trade; population and culture; and the European Community/European Union. Processes and interrelations are reviewed through a core-periphery model. Changing regional patterns are highlighted which suggest a movement away from a national focus for regional study to one which is more international.  相似文献   

20.
ABSTRACT

Datasets collecting the ever-changing position of moving individuals are usually big and possess high spatial and temporal resolution to reveal activity patterns of individuals in greater detail. Information about human mobility, such as ‘when, where and why people travel’, is contained in these datasets and is necessary for urban planning and public policy making. Nevertheless, how to segregate the users into groups with different movement and behaviours and generalise the patterns of groups are still challenging. To address this, this article develops a theoretical framework for uncovering space-time activity patterns from individual’s movement trajectory data and segregating users into subgroups according to these patterns. In this framework, individuals’ activities are modelled as their visits to spatio-temporal region of interests (ST-ROIs) by incorporating both the time and places the activities take place. An individual’s behaviour is defined as his/her profile of time allocation on the ST-ROIs she/he visited. A hierarchical approach is adopted to segregate individuals into subgroups based upon the similarity of these individuals’ profiles. The proposed framework is tested in the analysis of the behaviours of London foot patrol police officers based on their GPS trajectories provided by the Metropolitan Police.  相似文献   

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