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In modelling automated storage/retrieval systems, the assumption of random storage has been widely used to approximate the activity of the closest open location rule. Considering that the closest open location rule is so popular in practice, it is significant to validate the assumption, or identify under what conditions the assumption could be justified. In this study we show how the “true” activity distribution of the closest open location rule can be approximated by a “modified” uniform distribution. The modified distribution is then used to approximate the expected travel distance, which is simple to use yet accurate enough for practical purposes. We also show that the uniform approximation is valid even for different streams of demand and batch arrivals. [ABSTRACT FROM AUTHOR]

This article examines the cultural sources of underreported suicide deaths in South Korea. It analyzes two sets of suicide data compiled by two different government agencies. Noting the considerable undercounting of suicide deaths compiled by the National Statistical Office, it explores how the underreporting is linked to the Confucian norm of familism. Despite an effort to improve the quality of official suicide data, a reform in the death system is needed in order to gather accurate data for a better understanding of the increased suicides as well as for the development of more effective suicide prevention and intervention strategies. [ABSTRACT FROM AUTHOR]

Thallium (Tl) is highly toxic to humans compared with other heavy metals and metalloids, but the risk of its bioaccumulation has not been adequately considered. Thus, Tl uptake and translocation in barley and sunflower under hydroponics with the applications of diethylene triamine pentaacetic acid (DTPA) and citric acid were investigated. Thallium concentrations in roots of both the plants were higher than those in the shoots. Translocation index (TLI) of Tl in barley decreased from 14.9 to 10.0% with increasing Tl treatments in barley, but it increased from 5.9 to 7.5% in sunflower. The concentration of Tl in the barley tissues increased with DTPA applications, but it decreased with citric acid treatments. In contrast, Tl in the sunflower tissues decreased with DTPA treatments, while it increased with the applications of citric acid. However, Tl concentrations in the tissues of both plants were not significantly different between the two concentrations (5.0 and 30 mg/kg) of DTPA and citric acid applications. [ABSTRACT FROM AUTHOR]