Dynamic key ring update mechanism for mobile wireless sensor networks

Key distribution is an important issue to provide security in Wireless Sensor Networks (WSNs). Many of the key pre-distribution schemes proposed for static WSNs perform poorly when they are applied to Mobile Wireless Sensor Networks (MWSNs). In this paper, we propose Dynamic Key Ring Update (DKRU) mechanism for MWSNs. The aim of DKRU mechanism is to enable sensor nodes to update their key rings periodically during movement, by observing the frequent keys in their neighbors. Our mechanism can be used together with different key pre-distribution schemes and it helps to increase the performance of them. For the performance evaluation basis, we used our mechanism together with a location based key pre-distribution scheme. Our results show that DKRU mechanism increases the local and global connectivity when it is applied to MWSNs. Moreover, our mechanism does not cause a significant degradation in network resiliency

Employer-Provided Health Insurance and Labor Supply of Married Women

This work presents new evidence on the effect of husbands’ health insurance on wives’ labor supply. Previous cross-sectional studies have estimated a significant negative effect of spousal coverage on wives’ labor supply. However, these estimates potentially suffer from bias due to the simultaneity of wives’ labor supply and the health insurance status of their husbands. This paper attempts to obtain consistent estimates by using several panel data methods. In particular, the likely correlation between unobserved personal characteristics of husbands and wives—such as preferences for work—and potential joint job choice decisions can be controlled by using panel data on intact marriages. The findings, using data from the National Longitudinal Survey of Youth and the Current Population Survey, suggest that the negative effect of spousal coverage on labor supply found in cross-sections results mainly from spousal sorting and selection. Once unobserved heterogeneity is controlled for, a relatively smaller estimated effect of spousal coverage on wives’ labor supply remains.Health insurance, Labor supply, Marriage, Panel data