A matrix equation arising in statistical filter theory

Solution of Ricatti differential equation arising in statistical filering and optimal control theor

Atmospheric and surface compositional studies of Mercury and the moon

The atmosphere of the Moon and Mercury will be studied by means of high resolution spectroscopy of sodium and potassium resonance line emissions. The variation of metal vapor abundances with time, and with location will be measured with a view to understanding the origin and evolution of these elements in the atmospheres of the Moon and Mercury. Infrared spectroscopic measurements will be made of Mercury to determine the surface mineralogy, predicated on the availability of the Kuiper Airborne Observatory and infrared charge coupled device (CCD). During the past year, an excellent series of measurements were completed of the spatial distribution of sodium on Mercury. Sodium was found to be concentrated at the polar regions, and to be displaced towards the terminator by solar radiation pressure. Sodium and potassium were discovered in the atmosphere of the Moon. The ratio of sodium to potassium approximates that of the lunar regolith. Thermal infrared measurements of Mercury showed that the Christiansen peak was located shortwards of 8 micrometer, which indicates an acidic mineralogy

Revised estimates for ozone reduction by shuttle operation

Previous calculations by five different modeling groups of the effect of space shuttle operations on the ozone layer yielded an estimate of 0.2 percent ozone reduction for the Northern Hemisphere at 60 launches per year. Since these calculations were made, the accepted rate constant for the reaction between hydroperoxyl and nitric oxide to yield hydroxyl and nitrogen dioxide, HO2 + NO yields OH + NO2, was revised upward by more than an order of magnitude, with a resultant increase in the predicted ozone reduction for chlorofluoromethanes by a factor of approximately 2. New calculations of the shuttle effect were made with use of the new rate constant data, again by five different modeling groups. The new value of the shuttle effect on the ozone layer was found to be 0.25 percent. The increase resulting from the revised rate constant is considerably less for space shuttle operations than for chlorofluoromethane production, because the new rate constant also increases the calculated rate of downward transport of shuttle exhaust products out of the stratosphere

DEMOGRAPHIC RESEARCH

Background: Mexican women in the United States (US) have higher rates of fertility compared to other ethnic groups and women in Mexico. Whether variation in women’s access to family planning services or patterns of contraceptive use contributes to this higher fertility has received little attention. Objective: We explore Mexican women’s contraceptive use, taking into account women’s place in the reproductive life course. Methods: Using nationally representative samples from the US (National Survey of Family Growth) and Mexico (Encuesta National de la Dinámica Demográfica), we compared the parity-specific frequency of contraceptive use and fertility intentions for non-migrant women, foreign-born Mexicans in the US, US-born Mexicans, and whites. Results: Mexican women in the US were less likely to use IUDs and more likely to use hormonal contraception than women in Mexico. Female sterilization was the most common method among higher parity women in both the US and Mexico, however, foreign-born Mexicans were less likely to be sterilized, and the least likely to use any permanent contraceptive method. Although foreign-born Mexicans were slightly less likely to report that they did not want more children, differences in method use remained after controlling for women’s fertility intentionsPopulation Research Cente

Modelling workplace contact networks: the effects of organizational structure, architecture, and reporting errors on epidemic predictions

Face-to-face social contacts are potentially important transmission routes for acute respiratory infections, and understanding the contact network can improve our ability to predict, contain, and control epidemics. Although workplaces are important settings for infectious disease transmission, few studies have collected workplace contact data and estimated workplace contact networks. We use contact diaries, architectural distance measures, and institutional structures to estimate social contact networks within a Swiss research institute. Some contact reports were inconsistent, indicating reporting errors. We adjust for this with a latent variable model, jointly estimating the true (unobserved) network of contacts and duration-specific reporting probabilities. We find that contact probability decreases with distance, and research group membership, role, and shared projects are strongly predictive of contact patterns. Estimated reporting probabilities were low only for 0-5 minute contacts. Adjusting for reporting error changed the estimate of the duration distribution, but did not change the estimates of covariate effects and had little effect on epidemic predictions. Our epidemic simulation study indicates that inclusion of network structure based on architectural and organizational structure data can improve the accuracy of epidemic forecasting models.Comment: 36 pages, 4 figure

Mass-spectrometric investigation of reaction of oxygen atoms with methane

Mass spectrometric investigation of oxygen atoms reacting with methan

Development of high strength, brazed aluminum, honeycomb sandwich composites adaptable for both elevated and cryogenic temperature applications, volume I - Brazing alloy development and selection Final report, Jul. 1963 - Sep. 1966

Brazing alloy development for high strength aluminum honeycomb sandwich composites for elevated and cryogenic temperature application

Statistical Filtering of Space Navigation Measurements

Statistical filtering of space navigation measurement

Half of Women in New Hampshire Have Experienced Sexual Harassment at Work

In this brief, authors Kristin Smith, Sharyn Potter, and Jane Stapleton discuss the results of a 2018 Granite State Poll survey conducted by the University of New Hampshire on workplace sexual harassment in New Hampshire. They report that over half of women and nearly one-quarter of men in New Hampshire have been victims of sexual harassment at their workplaces during their lifetimes. Women are more likely to state they suffered work-related consequences (for example, financial loss, being fired or demoted) than men, but similar shares reported quitting their jobs as a result of the harassment. Sexual harassment is problematic for the workplace, as it reduces worker morale and job satisfaction, diminishes productivity, and increases absenteeism and worker withdrawal. The authors suggest that employers would do well to invest in prevention, such as bystander intervention training, and encourage victims’ use of supports to mitigate the negative effects of workplace sexual harassment