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171.
172.
俄罗斯太平洋石油管道建设的地缘政治分析 总被引:2,自引:0,他引:2
随着中俄原油管道建成投入运营,东北亚地区的石油管道之争似乎告一段落。解读管道之争背后真正在起决定作用的地缘因素,对一个国家的能源安全和能源战略更有借鉴意义。从地理学空间关系的相互依赖性、干扰因素、距离、运输方式等视角对俄罗斯太平洋管道之争的始末波折及未来可能出现的问题进行分析,可探究地缘环境要素及空间关系的各个方面是如何影响到一个国家对能源安全的控制权、如何影响对本国战略利益的保障等地缘纷争的核心内容。 相似文献
173.
随着犯罪的频繁发生,犯罪热点受到越来越多相关部门的关注。在此,应用不同的空间分析方法,研究犯罪热点的分布,提出预防犯罪的措施,以期为社会稳定提供参考。 相似文献
174.
Junjian Cui M.Eng. Xiaorui Zhao M.Eng. Nini Liu M.Sc. Sergey Morgachev M.A. Daixi Li M.Eng. 《Journal of forensic sciences》2019,64(2):422-430
In this study, an automatic and robust crime scene shoeprint retrieval method is proposed. As most shoeprints left at crime scenes are randomly partial and noisy, crime scene shoeprint retrieval is a challenging task. To handle partial, noisy shoeprint images, we employ denoising deep belief network (DBN) to extract local features and use spatial pyramid matching (SPM) to obtain a local‐to‐global matching score. In this study, 536 query shoeprint images from crime scenes and a large scale database containing 34,768 shoeprint images are used to evaluate the retrieval performance. Experimental results show that the proposed method outperforms other state‐of‐the‐art methods in terms of retrieval accuracy, feature dimension, and retrieval speed. The proposed method achieves a cumulative match score (CMS) of 65.67% at top 10 which is 5.60% higher than the second best performing method. 相似文献
175.
176.
Adolescents have begun to initiate sexual activity at increasingly early ages in the past few decades. Using a sample of 2,494
adolescents from the National Longitudinal Survey of Youth (NLSY97), structural and parental process variables were examined
in the prediction of sexual onset. Results indicated that the age at which youth initiate sexual intercourse is related to
the structural characteristics of their grandmothers and mothers, as well as puberty, gender, and race. There is support for
partial mediation of the effects of these grandmother characteristics via mother characteristics and parental process. Results
are discussed within the framework of the life course perspective and provide support for the importance of previous generations
in the explanation of adolescent sexual behavior. Implications for families and adolescents are also addressed.
Katherine A. Johnson, is a doctoral student at the University of Nebraska–Lincoln. Her research interests include the study
of crime, gender, and high-risk youth using both qualitative and quantitative methodology.
Kimberly A. Tyler, is an associate professor in the Department of Sociology at the University of Nebraska–Lincoln. Her research
interests include homelessness, child abuse and neglect, victimization, and high-risk behaviors among adolescents and youth. 相似文献
177.
This study utilizes geographic information systems (GIS) and spatial analysis (SA) technology to address the problems associated with prediction of location and effective recovery of dumped and scattered human remains in Louisiana. The goals are to determine if a selective bias exists in Louisiana as to where and when human remains are dumped and to assess whether or not geographically specific patterns exist in the dispersal of human remains. We hypothesized that a positive relationship exists between postmortem interval (PMI) and dispersal distance, and that there are negative relationships between PMI and dispersal direction and between dispersal direction and distance. Our results indicate that, in Louisiana, remains are more often dumped in rural areas away from a structure, and are found within (1/4) mile of the nearest road. For Louisiana, no seasonal bias was found in the analysis of when remains are dumped. Furthermore, with the exception of the relationship between PMI and the shortest distance remains were dispersed, no geographically specific patterns were detected in the analyses of dispersal distance, dispersal direction, and PMI. 相似文献
178.
Tony H. Grubesic 《Journal of Quantitative Criminology》2006,22(1):77-105
One of the fundamental challenges in crime mapping and analysis is pattern recognition. Efforts and methods to detect crime
hot-spots, or geographic areas of elevated criminal activity, are wide ranging. For aggregate data, such as total crime events
in a census tract(s), measures of spatial autocorrelation have proven useful. For disaggregate data (i.e. individual crime
events), kernel density smoothing and non-hierarchical cluster analysis (e.g. k-means), are widely used. Non-hierarchical techniques are particularly effective in delineating geographic space into areas
of higher or lower crime concentrations, because each observation is assigned to one and only one cluster. The resulting set
of partitions provides clear-cut spatial boundaries that can be used for hot-spot evaluation and interpretation. However,
the strength of non-hierarchical methods can also be viewed as a weakness. Although the hard-clustering of observations into
a set of discrete clusters is helpful, there are many cases where ambiguity exists in the data. In such cases, a more generalized
approach for hot-spot detection would be helpful. The purpose of this paper is to explore the use of a generalized partitioning
method known as fuzzy clustering for hot-spot detection. Functional and visual comparisons of fuzzy clustering and two hard-clustering
approaches (medoid and k-means), across a range of cluster values are analyzed. The empirical results suggest that a fuzzy clustering approach is
better equipped to handle intermediate cases and spatial outliers.
相似文献
Tony H. GrubesicEmail: |
179.
Previous work has documented the similar importance of developmental domains in accounting for adolescent deviance in different racial/ethnic groups (e.g., Vazsonyi A. T., and Flannery, D. J., 1997, J. Early Adolesc. 17(3): 271–293). The current investigation is a replication and extension of this line of work. It examined the importance of the family (closeness, monitoring, and conflict) and school (grades, homework time, educational aspirations, and commitment) domains on a sample of adolescent (mean age = 16.4 years) African American and Caucasian youth (N = 809). The following important findings were made: (a) developmental processes including family and school domain variables and deviance were very similar for African American and Caucasian youth; (b) both developmental domains revealed independent predictive relationships with a number of different measures of adolescent deviance in both groups; and (c) the 2 domains uniquely accounted for 25% and 37% of the variance explained respectively in African American and Caucasian adolescent total deviance. 相似文献
180.
Janet Warren Roland Reboussin Robert R. Hazelwood Andrea Cummings Natalie Gibbs Susan Trumbetta 《Journal of Quantitative Criminology》1998,14(1):35-59
This study, derived from a sample of 108 serial rapists (rapes=565), examines the relationship between demographic, crime scene, and criminal history variables and the distance traveled by serial rapists in order to offend. The pattern of offenses perpetrated by each of the 108 serial offenders as it relates to his place of residence is also analyzed in terms of known characteristics of the offender and his offenses. The theoretical focus of the study integrates premises derived from criminal investigative analysis, environmental criminology, ethnographic geography, journey to crime research, and criminal geographic targeting to explore the cognitive symmetry between the how and the where of serial sexual offenses. These components or dimensions of serial crime are explored in an attempt to aid law enforcement in their investigation of hard-to-solve serial crimes. 相似文献