The issues of marital stability and family composition and the income maintenance experiments

Income distribution ; Public welfare ; Income

Earnings of Black and White Youth and Their Relation to Poverty

This paper examines the relation between youth employment and poverty for black and white families. An increase in the employment proportions of black men ages 16–19, which have lagged far behind their white counterparts, would reduce poverty among blacks to a moderate but meaningful degree. We provide evidence of a small positive feedback relation between black youth employment and family incomes that would magnify gains in both variables if either variable were increased. We also provide evidence that improvements in labor market conditions that affect youth employment, in the educational attainments of black youth, and in other policy-related variables would raise both youth employment and their family incomes.

<a study of the effects of protective filters and lenses on color judgement< final report

Effect of protective filters and lenses on color judgment by human

Shifts in U.S. Relative Wages: The Role of Trade, Technology, and Factor Endowments

This paper investigates three hypotheses to account for the observed shifts in U.S. relative wages of less educated workers compared to more educated workers during the period from 1967 to 1992: (1) increased import competition, (2) changes in the relative supplies of labor of different educational levels, and (3) changes in technology. Our analysis relies on a basic relationship of the standard general equilibrium trade model that relates changes in product prices to factor price changes and factor shares, together with information about changes in the composition of output and trade, within-industry factor use, and factor supplies. For the period from 1967 to 1973, we conclude that the relative increase in the supply of well-educated labor was the dominant economic force that narrowed the wage gap among workers of different educational levels. In the 1980s and early 1990s, however, the wage gap between more educated and less educated workers widened sharply, despite the continued relative increase in the supply of workers with more education. We conclude that increased import competition cannot account for the observed increase in inequality among the major education groups, although it could have been a contributory cause of the decrease in the relative wages of the least educated workers. Instead, we find support for technical progress that is saving of less educated labor and that is more rapid in some manufacturing sectors intensively using highly educated labor as the dominant force in widening the wage gaps among college-educated workers, workers with a completed high school education, and workers with 1–11 years of schooling. Finally, we use the Deardorff-Staiger model, which allows changes in the factor content of trade to reveal the effects of trade on relative factor prices. Our empirical tests reinforce the conclusion that increased import competition between 1977 and 1987 was not the dominant force in widening the wage

Improving the Employment Rates of People with Disabilities through Vocational Education

During the 2001-8 period, the employment rate of people with a disability remained remarkably low in most western economies, hardly responding to better macroeconomic conditions and favourable anti-discrimination legislation and interventions. Continuing health and productivity improvements in the general population are leaving people with disabilities behind, unable to play their role and have their share in the increasing productive capacity of the economy. This paper combines dynamic panel econometric estimation with longitudinal data from Australia to show that vocational education has a considerable and long lasting positive effect on the employment participation and productivity of people with disabilities.vocational training, productivity, disabilities, employment, dynamic panel regression

AIRNET: A real-time comunications network for aircraft

A real-time local area network was developed for use on aircraft and space vehicles. It uses token ring technology to provide high throughput, low latency, and high reliability. The system was implemented on PCs and PC/ATs operating on PCbus, and on Intel 8086/186/286/386s operating on Multibus. A standard IEEE 802.2 logical link control interface was provided to (optional) upper layer software; this permits the controls designer to utilize standard communications protocols (e.g., ISO, TCP/IP) if time permits, or to utilize a very fast link level protocol directly if speed is critical. Both unacknowledged datagram and reliable virtual circuit services are supported. A station operating an 8 MHz Intel 286 as a host can generate a sustained load of 1.8 megabits per second per station, and a 100-byte message can be delivered from the transmitter's user memory to the receiver's user memory, including all operating system and network overhead, in under 4 milliseconds

Preliminary results of the Mariner IV radio occultation measurements of the upper atmosphere of Mars

Mariner IV radio occultation measurements of Mars upper atmospher

Proton transport and torque generation in rotary biomotors

We analyze the dynamics of rotary biomotors within a simple nano-electromechanical model, consisting of a stator part and a ring-shaped rotor having twelve proton-binding sites. This model is closely related to the membrane-embedded F$_0$ motor of adenosine triphosphate (ATP) synthase, which converts the energy of the transmembrane electrochemical gradient of protons into mechanical motion of the rotor. It is shown that the Coulomb coupling between the negative charge of the empty rotor site and the positive stator charge, located near the periplasmic proton-conducting channel (proton source), plays a dominant role in the torque-generating process. When approaching the source outlet, the rotor site has a proton energy level higher than the energy level of the site, located near the cytoplasmic channel (proton drain). In the first stage of this torque-generating process, the energy of the electrochemical potential is converted into potential energy of the proton-binding sites on the rotor. Afterwards, the tangential component of the Coulomb force produces a mechanical torque. We demonstrate that, at low temperatures, the loaded motor works in the shuttling regime where the energy of the electrochemical potential is consumed without producing any unidirectional rotation. The motor switches to the torque-generating regime at high temperatures, when the Brownian ratchet mechanism turns on. In the presence of a significant external torque, created by ATP hydrolysis, the system operates as a proton pump, which translocates protons against the transmembrane potential gradient. Here we focus on the F$_0$ motor, even though our analysis is applicable to the bacterial flagellar motor.Comment: 24 pages, 5 figure