Reliable and accurate estimation of residential segregation between population groups is important for understanding the extent of social cohesion and integration in our society. Although there have been considerable methodological advances in the measurement of segregation over the last several decades, the recently developed measures have not been widely used in the literature, in part due to their complex calculation. To address this problem, we have implemented several newly proposed segregation indices in R, an open source software environment for statistical computing and graphics, as a package called seg. Although there are already a few standalone applications and add-on packages that provide access to similar methods, our implementation has a number of advantages over the existing tools. First, our implementation is flexible in the sense that it provides detailed control over the calculation process with a wide range of input parameters. Most of the parameters have carefully chosen defaults, which perform acceptably in many situations, so less experienced users can also use the implemented functions without too much difficulty. Second, there is no need to export results to other software programs for further analysis. We provide coercion methods that enable the transformation of our output classes into general R classes, so the user can use thousands of standard and modern statistical techniques, which are already available in R, for the post-processing of the results. Third, our implementation does not require commercial software to operate, so it is accessible to a wider group of people.

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In the munitions industry, there have been considerable efforts spent to develop low-cost, simply fabricated, easily wearable, and biocompatible bulletproof armors. Recently, long fiber-reinforced composites and shear thickening fluids (STFs) were inceptively utilized to improve bulletproof performance with solid or fabric materials. In this study, Hanji, a cornstarch suspension, Korean traditional long fiber paper, and a well-known STF, respectively, were examined for bulletproof applications to evaluate their own effects on bulletproof performance; tests were carried out in the field and finite element analysis (FEA) was performed to evaluate the behavior of materials regarding with perforated clay areas from in-field tests. It was found that both Hanji and STF influenced the bullet penetration by two factors, namely the momentum of bullet and stress propagation. The cornstarch suspension, rather than Hanji, showed outstanding performance in decreasing the linear velocity of the bullet and minimized the stress propagation to the protecting object. Thus, although STF performed a key role in bulletproof performance, Hanji also proved to be a suitable material as an exterior covering for absorbing the initial impact stress and maintaining the durability and stability of the armor itself.