Thin Film Formation During Splashing of Viscous Liquids

After impact onto a smooth dry surface, a drop of viscous liquid initially spreads in the form of a thick lamella. If the drop splashes, it first emits a thin fluid sheet that can ultimately break up into droplets causing the splash. Ambient gas is crucial for creating this thin sheet. The time for sheet ejection, $t_{ejt}$, depends on impact velocity, liquid viscosity, gas pressure and molecular weight. A central air bubble is trapped below the drop at pressures even below that necessary for this sheet formation. In addition, air bubbles are entrained underneath the spreading lamella when the ejected sheet is present. Air entrainment ceases at a lamella velocity that is independent of drop impact velocity as well as ambient gas pressure.Comment: 8 pages, 11 figure

Ultrafast Interference Imaging of Air in Splashing Dynamics

A drop impacting a solid surface with sufficient velocity will emit many small droplets creating a splash. However, splashing is completely suppressed if the surrounding gas pressure is lowered. The mechanism by which the gas affects splashing remains unknown. We use high-speed interference imaging to measure the air beneath all regions of a spreading viscous drop as well as optical absorption to measure the drop thickness. Although an initial air bubble is created on impact, no significant air layer persists until the time a splash is created. This suggests that splashing in our experimentally accessible range of viscosities is initiated at the edge of the drop as it encroaches into the surrounding gas

A CLASS OF SEPARABILITY FLEXIBLE FUNCTIONAL FORMS

Quadratic flexible forms, such as the translog and generalized Leontief, are separability inflexible. That is, separability restrictions render them inflexible with regard to separable structures. A class functional forms is proposed that is flexible with regard to general production structures and remains flexible regarding weakly separable structures when separability restrictions are imposed, thus permitting tests of the separability hypothesis. Additionally, the restricted forms are parsimonious; that is they contain the minimum number of parameters with which flexibility can be achieved.Research Methods/ Statistical Methods,

Analysis of San Luis Obispo Housing Elements

This project focuses on analysis and recommendations for housing elements within San Luis Obispo County. The project details housing element requirements made by the State of California Housing and Community Development Department and how the incorporated cities of San Luis Obispo meet these requirements. Cities analyzed include Arroyo Grande, Atascadero, Grover Beach, Morro Bay, Paso Robles, Pismo Beach, and San Luis Obispo

An Analysis of the Effectiveness of Online Peer Feedback at the United States Air Force Academy

This thesis explores the effectiveness of the Air Force Academy\u27s Department of English local area network peer feedback system. Four main questions were examined. These questions explored a) whether students reported improvement in their writing, b) whether students reported that feedback is worthwhile, c) whether students reported that LAN sessions increase enjoyment of writing, and d) what types of feedback the students 1) received and 2) found most helpful. Three groups were studied. Forty-six students received feedback online, fifty students received feedback face to face, and thirty-three students did not receive feedback. Comparisons were made for the questions mentioned above to see if there was any difference in the responses based on the method of feedback the students received. The results of the study suggest that students\u27 perceived writing improvement is not affected by the peer feedback program. Peer feedback is successful in that students who participate find it to be worthwhile and at least one group believes that it makes writing more enjoyable. Finally, the two feedback groups reported receiving and wanting different types of feedback. The online group receives and prefers feedback on content, and the face to face group receives and prefers feedback on flow

Severing Ties: The Case For Indefinite Orders Of Protection For Survivors Of Domestic Violence

Severing Ties: The Case For Indefinite Orders Of Protection For Survivors Of Domestic Violenc

MIT LMFBR blanket research project. Quarterly progress report, July 1, 1975--September 30, 1975

Research progress on physics experiments and calculations for LMFBR breeding blankets is briefly reported. (JWR

Herdís & Ólína: The Poetry of Everyday Life

The twin sisters Herdís Andrésdóttir and Ólína Andrésdóttir were born on the island Flatey in Breiðafjörður, western Iceland, in 1858. Following the death of their father at sea three years later, the family was dispersed and the sisters did not see each other until half a century later, when they were reunited in Reykjavík. In the intervening years both sisters had become well known as capable verse-makers in the traditional style, but it had never, it seems, occurred to them to write any of their poems down, let alone publish them. They were encouraged by friends to do so, and in 1924 they brought out a collection of their verse, entitled simply Ljóðmæli (Poems). Their poetry was highly traditional both in its form, which principally made use of rímur and ballad metres, and in terms of its subject matter, dealing with nature, reflections on life’s joys and sorrows and so on. Ólína, like her cousin Theodóra Thoroddsen, also contributed to the revival of the þula, a form of poetry traditionally associated with children. The book sold well, and a second edition, with some additional poems, came out in 1930. A third edition was brought out in 1976, long after their deaths, containing much new material; this edition has since been reprinted twice. Critical reception was overwhelmingly favourable, both in the learned and more popular press. Though somewhat at odds with the literary establishment of the day, they nevertheless had several powerful supporters among the literary and intellectual élite, foremost among them professor Sigurður Nordal. Despite having been “world-famous in Iceland” in their old age, Herdís and Ólína are little known today, and their work – much of it very fine indeed – has yet to receive the scholarly attention it deserves