Using Dasymetric Mapping for Spatially Aggregated Crime Data

With availability of crime data to the public via sources such as the Uniform Crime Reports, and increasing geographic information system (GIS) capabilities for mapping crime, macro-level studies of crime have advanced knowledge of how crime is distributed over large areas. Choropleth mapping, commonly used in macro-level studies, visually displays data by assigning the number of crimes or crime rate to the corresponding spatial unit and using different shades or textures for each value or classified values creating a thematic map. However, crime incidents or crime rates are not dispersed evenly within spatial units, and choropleth mapping masks the underlying nuances of the distribution. Artificial boundaries, along with variations in the size of the unit of analysis, can further distort the true distribution of crime. Dasymetric mapping provides a methodology for refining the distribution of crime within a spatial unit. It does so by using additional data, such as land use and census data, to provide a realistic estimate of how crime may be distributed within the units of analysis. Dasymetric mapping is also useful in creating density maps to reveal clusters of crime normally masked with choropleth maps. This paper will show how dasymetric mapping can estimate the spatial distribution of aggregate level residential burglary within political boundaries in Massachusetts based on land use and housing data.     

“A Plague on both Your Houses?”: Risks,Repeats and Reconsiderations of Urban Residential Burglary

Research has shown that mapping techniques are useful in forecasting future crime events. However, the majority of prospective mapping techniques has focused on the event-dependent influence of instigator incidents on subsequent incidents and does not explicitly incorporate the risk heterogeneity of the setting. The study here discussed is a modest attempt to address this issue by using a two-step process: first, using risk terrain modeling, we operationalized the “environmental backcloth,” (the risk heterogeneity of an area) to forecast locations of residential burglaries in the urban city of Newark, New Jersey. Second, using the near repeat calculator, we assessed the variability of underlying risk between different types of residential burglaries. A discussion of the findings and the joint utility of these approaches is provided.     

数字地球与公安网络空间信息系统

数字地球与公安网络空间信息系统这一课题,基于数字地球的技术框架体系和从传统GIS到现代Web GIS的演变,结合公安空间数据基础设施的建设,探讨了建立公安空间数据仓库和Web GIS站点的问题,提出了公安网络空间信息系统的体系结构和建设内容.     

城市应急管理系统功能与GIS功能应用

综述了目前城市应急管理系统的基本功能,阐述了地理信息系统（GIS）功能在城市应急管理系统设计开发上的基本应用。     

A randomized experimental study of sharing crime data with citizens: Do maps produce more fear?

The larger roles of the community in crime prevention and improvements in technology have increased police–citizen communication and the distribution of information from police departments to private citizens. Combined, these changes have led to the current movement among law enforcement agencies toward sharing both summary reports and maps of crime with community groups. Although the dissemination of crime information is intended to benefit community members, there is a lack of empirical evidence demonstrating the effects of crime mapping on citizen perceptions and fear of crime. This experiment compared three formats for disseminating crime data; two popular types of crime maps (i.e., graduated symbol and density) and the traditional tabular format of crime statistics. A randomized experimental design was used to measure residents fear of crime and their perception of the safety of different areas of Redlands, CA. Overall, residents who viewed either type of map reported less fear than those who viewed tabular statistics. Respondents who viewed graduated symbol maps consistently reported less fear than either density maps or tabular statistics. However, there were differences depending on the type of map. While graduated symbol maps were associated with the lowest levels of fear of robbery, theft or assault; density maps produced different reactions depending on the area of the city. Finally, the maps did not stigmatize high crime areas of Redlands. Where statistically significant differences existed, respondents who were given maps were more likely to recommend someone move into an area than those who were given tabular statistics.     

禁毒情报地理信息系统应用研究

禁毒情报与地理信息系统的结合可以把与禁毒有关的信息资源与对应空间地理数据集成在GIS平台之上,更好地实现信息的共享、智能筛选和案件线索关联分析。在此基础上通过研究禁毒情报地理信息系统在关联分析图形化、强制关联、“模式化”智能侦查分析等方面的应用技术,可以提高效率、节约警力、促进科技强警。     

A Method to Interpolate Osteon Volume Designed for Histological Age Estimation Research

Aging adult skeletal material is a crucial component of building the biological profile of unknown skeletal remains, but many macro- and microscopic methods have challenges regarding accuracy, precision, and replicability. This study developed a volumetric method to visualize and quantify histological remodeling events in three dimensions, using a two-dimensional serialized approach that applied circular polarizing microscopy and geographic information systems protocols. This approach was designed as a tool to extend current histological aging methodologies. Three serial transverse sections were obtained from a human femoral midshaft. A total sample size of 6847 complete osteons from the three sections was identified; 1229 osteons connected between all sections. The volume of all connected osteons was interpolated using ArcGIS area calculations and truncated cone geometric functions. Each section was divided into octants, and two random samples of 100 and of 30 connected osteons from each octant were generated. Osteon volume was compared between the octants for each random sample using ANOVA. Results indicated that the medial aspect had relative uniformity in osteon volume, whereas the lateral aspect showed high variability. The anterolateral–lateral octant had significantly smaller osteon volume, whereas the posterior–posterolateral octant had significantly larger osteon volume. Results also indicated that a minimum of 100 osteons is statistically more robust and more representative of normal osteon distribution and volume; the use of 30 osteons is insufficient. This research has demonstrated that osteon volume can be interpolated using spatial geometry and GIS applications and may be a tool to incorporate into adult age-at-death estimation techniques.     

GIS在景观生态学中的应用

近日，三元集团公司召开了劳模座谈会，集团公司党委书记、董事长张福平，总经理薛刚，工会主席宋春来及党委常委、政工部部长马辉等领导参加了座谈会，大会由宋春来主持。     

地理信息系统与空间数据库研究

本文分析了地理信息系统的基本发展情况，对空间数据库的特点．分类详细的进行了描述。以某土地资源空间数据库的建立为例，展示了空间数据库的应用情况。