16,926 research outputs found
Thermally operated valve Patent
Gas valve operated by thermally expanding and contracting devic
Chassis unit insert tightening-extract device
The invention relates to the insertion and extraction of rack mounted electronic units and in particular to a screw thread insert tightening and extract device, for chassis units having a collar which may be rotatably positioned manually for the insert tightening or extraction of various associated chassis units, as desired
The intergenerational correlation in AFDC participation: Welfare trap or poverty trap?
Several recent studies have shown that daughters whose mothers have participated in the welfare program Aid to Families with Dependent Children (AFDC), are themselves more likely to participate in AFDC when they head their own household. Other studies have shown that the earnings of parents and their children are highly correlated across generations. This suggests that any variable correlated with income such as AFDC participation will also be correlated across generations. This paper uses data from the original and youth cohorts of the National Longitudinal Surveys to investigate the question of whether the link in mother-daughter welfare participation is a causal relationship, or whether it can be explained by the expected intergenerational correlation in earnings. Several reduced-form probit equations are estimated, and attention is directed to the potential endogeneity of key explanatory variables. The empirical findings suggest that much of the observed correlation in AFDC participation across generations can be explained by the intergenerational correlation of income and other family characteristics.
An empirical analysis of the welfare magnet debate using the NLSY
This paper examines the extent to which differences in welfare generosity across states lead to interstate migration. Using microdata from the National Longitudinal Survey of Youth between 1979 and 1992, we employ a quasi-experimental design that utilizes the categorical eligibility of the welfare system. The "treatment" group consists of all those in the survey who appear eligible to participate in Aid to Families with Dependent Children. The "control" group contains those who are poor but ineligible for other reasons. The pattern of cross-state moves among poor single women with children who are likely to be eligible for benefits (treatment-group members) is compared to the pattern among other poor households. We find little evidence indicating that welfare-induced migration is a widespread phenomenon.
Fabrication and Electrical Characterization of Fully CMOS Si Single Electron Devices
We present electrical data of silicon single electron devices fabricated with
CMOS techniques and protocols. The easily tuned devices show clean Coulomb
diamonds at T = 30 mK and charge offset drift of 0.01 e over eight days. In
addition, the devices exhibit robust transistor characteristics including
uniformity within about 0.5 V in the threshold voltage, gate resistances
greater than 10 G{\Omega}, and immunity to dielectric breakdown in electric
fields as high as 4 MV/cm. These results highlight the benefits in device
performance of a fully CMOS process for single electron device fabrication.Comment: 7 pages, 7 figure
A Working Bibliography of David Drake's Writing
David Drake sold his first story in 1966 and continues to write novels, short fiction, essays and other miscellaneous pieces. He is most well-known for his military science fiction, but his fiction spans multiple subgenres within science fiction and fantasy. This bibliography includes his books (novels, collections of stories, and titles for which he wrote plot outlines); books he edited; his short fiction; and miscellaneous writings (essays, comments, book introductions and odd pieces.) The list will be updated at his official web site: http://david-drake.com
An experimental investigation of high amplitude panel flutter
Aluminum panel flutter tests at supersonic Mach number
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