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Environmental criminologists have correlated crime patterns with the environmental and physical layout of places where crimes occur. This paper reports on some of the findings derived from a major research carried out in Tehran, focusing on the link between built environment and residential burglary. After a brief review of crime prevention approaches in the built environment and their theoretical basis, the paper examines how burglars select their targets, and investigates the significance of geographical distance and target hardening for crime prevention. It shows the limitations of distance and target hardening as deterrents, their potential impact on deepening the city's socio-spatial divide, and their negative implications for the quality of the urban environment. 相似文献
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Mahdi Sohrabi-Haghighat Mohammadreza Rostami 《Journal of Combinatorial Optimization》2017,34(1):218-232
The geometric-arithmetic index was introduced in the chemical graph theory and it has shown to be applicable. The aim of this paper is to obtain the extremal graphs with respect to the geometric-arithmetic index among all graphs with minimum degree 2. Let G(2, n) be the set of connected simple graphs on n vertices with minimum degree 2. We use linear programming formulation and prove that the minimum value of the first geometric-arithmetic \((GA_{1})\) index of G(2, n) is obtained by the following formula:
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$$\begin{aligned} GA_1^* = \left\{ \begin{array}{ll} n&{}\quad n \le 24, \\ \mathrm{{24}}\mathrm{{.79}}&{}\quad n = 25, \\ \frac{{4\left( {n - 2} \right) \sqrt{2\left( {n - 2} \right) } }}{n}&{}\quad n \ge 26. \\ \end{array} \right. \end{aligned}$$
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Katembu Stephen Xu Qiang Rostami Hadiseh Nowparast Recio Guillermo Sommer Werner 《Journal of Nonverbal Behavior》2022,46(3):247-267
Journal of Nonverbal Behavior - Facial expressions contribute to nonverbal communication, social coordination, and interaction. Facial expressions may reflect the emotional state of the expressor,... 相似文献
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Social Participation, Sense of Community and Social Well Being: A Study on American, Italian and Iranian University Students 总被引:2,自引:0,他引:2
Elvira Cicognani Claudia Pirini Corey Keyes Mohsen Joshanloo Reza Rostami Masoud Nosratabadi 《Social indicators research》2008,89(1):97-112
Aim of the study was to assess the relationship between social participation and Sense of Community in a sample of University
students and the impact of such variables on Social well being. A further aim was to assess the generality of the relationships
between these constructs across different countries, and specifically, the USA, Italy and Iran. The sample includes 200 Italian,
125 American and 214 Iranian University students, male and female. Results show higher levels of social participation, Sense
of Community and Social well being among American students. Sense of Community is positively correlated with social participation
in all three samples; however, only among Italian students social participation positively predicts Social well being. Implications
of results will be discussed. 相似文献
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Cindy X. Feng Mehdi Rostami Longhai Li 《Journal of Statistical Computation and Simulation》2017,87(12):2384-2410
In practice, survival data are often collected over geographical regions. Shared spatial frailty models have been used to model spatial variation in survival times, which are often implemented using the Bayesian Markov chain Monte Carlo method. However, this method comes at the price of slow mixing rates and heavy computational cost, which may render it impractical for data-intensive application. Alternatively, a frailty model assuming an independent and identically distributed (iid) random effect can be easily and efficiently implemented. Therefore, we used simulations to assess the bias and efficiency loss in the estimated parameters, if residual spatial correlation is present but using an iid random effect. Our simulations indicate that a shared frailty model with an iid random effect can estimate the regression coefficients reasonably well, even with residual spatial correlation present, when the percentage of censoring is not too high and the number of clusters and cluster size are not too low. Therefore, if the primary goal is to assess the covariate effects, one may choose the frailty model with an iid random effect; whereas if the goal is to predict the hazard, additional care needs to be given due to the efficiency loss in the parameter(s) for the baseline hazard. 相似文献
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