Evolution of planetesimal velocities

A self-consistent set of equations for the velocity evolution of a general planetesimal population is presented. The equations are given in a form convenient for calculations of the early stages of planetary accumulation when it is necessary to model the planetesimal swarm by methods of gas dynamics, rather than follow the orbital evolution of individual bodies. Steady state velocities of a simple planetesimal population consisting of two different sizes of bodies are calculated. Dynamical friction is found to be an important mechanism for transferring kinetic energy from the larger planetesimals to the smaller ones. When the small planetesimals are relatively abundant, gas drag and inelastic collisions among the smaller bodies are of comparable importance for dissipating energy from the population

"The land with the midas touch": British perceptions of New Zealand, 1935-1979

For many British commentators, especially on the social democratic left, mid-century New Zealand, or at least its ‘settler’ population, was a society with much to admire – particularly in the field of social policy. British Labour Party leaders looked enviously at, for example, the Dominion’s 1938 Social Security Act, legislation which significantly added to the provision of state-backed health care and social security for New Zealanders. This was seen as building on earlier reforms which had established New Zealand’s reputation as a ‘social laboratory’, a key component of the Dominion’s sense of identity. In addition, the very fact of its Commonwealth membership made the potential transfer of its practices to the ‘motherland’ all the more viable. New Zealand was thus a key participant in the transnational exchange of ideas about social welfare which characterized the era. But after the Second World War doubts began to spread, both inside and outside of New Zealand. These were focused on, for instance, a purportedly ossified political system and concerns over the absence of a broadly-based intellectual culture. From being a ‘social laboratory’ which could be fruitfully emulated, New Zealand became an example of a society in which a lack of vision and foresight could prove highly problematic

Baroclinic Vorticity Production in Protoplanetary Disks; Part I: Vortex Formation

The formation of vortices in protoplanetary disks is explored via pseudo-spectral numerical simulations of an anelastic-gas model. This model is a coupled set of equations for vorticity and temperature in two dimensions which includes baroclinic vorticity production and radiative cooling. Vortex formation is unambiguously shown to be caused by baroclinicity because (1) these simulations have zero initial perturbation vorticity and a nonzero initial temperature distribution; and (2) turning off the baroclinic term halts vortex formation, as shown by an immediate drop in kinetic energy and vorticity. Vortex strength increases with: larger background temperature gradients; warmer background temperatures; larger initial temperature perturbations; higher Reynolds number; and higher resolution. In the simulations presented here vortices form when the background temperatures are $\sim 200K$ and vary radially as $r^{-0.25}$, the initial vorticity perturbations are zero, the initial temperature perturbations are 5% of the background, and the Reynolds number is $10^9$. A sensitivity study consisting of 74 simulations showed that as resolution and Reynolds number increase, vortices can form with smaller initial temperature perturbations, lower background temperatures, and smaller background temperature gradients. For the parameter ranges of these simulations, the disk is shown to be convectively stable by the Solberg-H{\o}iland criteria.Comment: Originally submitted to The Astrophysical Journal April 3, 2006; resubmitted November 3, 2006; accepted Dec 5, 200

Models of planetary rings

The Voyager occultations provide several uniform and high quality data sets for Saturn, Uranus, and Neptune. These data are intercompared, and theoretical models for the particle sizes and the particle transport are developed. The major topics covered include: ring size distribution, torques and resonances, and satellite wakes

The Ursinus Weekly, May 3, 1943

WSGA has dinner for Ursinus women to install officers • Combined Y\u27s present illustrated lecture at vespers Sunday night • May Day celebration features coronation ceremony, plays • 60 students sign to donate blood • United aircraft offers engineering fellowships • Schwartz, Fairlie chosen to head Y next semester • Former Ursinus athlete killed while in training • Frosh debaters present trial at annual banquet • Phys-edders to return for fall sport program • Prospective students take exams on open house day • Scope of IRC explained by Dr. White at banquet • Freeland 305 jinxed as six leave in past year • Navy to interview 17 men • Dramatic fraternity adds six members tomorrow • France forever speaker is refugee from German prison camp in Europe • Ruby will be out May 15, says Curtis • Walter Sanborn addresses Weekly banquet Monday • Y heads announce new committees • Pre-meds hear Dr. Appleton speak on dental diseases • English Club draws for books tonight • Observant Oscar dispenses dope on what a plane spotter spots • Frosh-juniors lose to soph-seniors, 4-0; Grau pitches no-hitter • Tennis team downs Temple; high wind handicaps coeds • Shreiner-Clamer leads girls\u27 softball league • Ursinus girls beat Bryn Mawr varsity • Snell\u27s belles turn aside Penn girls 23-12 in spite of playing indoor game • Phys Ed Club plans picnic • Commandos go outside to sniff spring odors • Girls elect Jane Kircher and Tinker Harmer to WAA • Curtain Club loses stage manager as Clark D. Moore graduateshttps://digitalcommons.ursinus.edu/weekly/1763/thumbnail.jp

The capacity of Scotland’s community right to buy legislation to contribute to ecological sustainability

The principal aim of this thesis is to contribute to sustainability debates. Specifically, this thesis aims to assess the capacity of the statutory community rights to buy – part of Scotland’s wider land reform framework – to contribute to ecological sustainability. ‘Ecological sustainability’, in context of this thesis, is the ultimate goal of humanity successfully living within the ecological limits of the Earth. This thesis outlines that these community rights to buy are defined and affected by both sustainable development and property law. Therefore, it seeks to interrogate the extent to which both of these aspects are influenced by anthropocentrism, rather than ecocentrism, and the impact this has on the capacity of the community rights to buy to contribute to the achievement of ecological sustainability. Three central arguments are important in this regard: the spectrum between anthropocentric and ecocentric understandings of sustainable development; how imbuing responsibilities in ownership can help to bridge the gap between these two understandings; and how the structuring effect of property law resists placing responsibilities on ownership, thus impeding the ability to find a more appropriate point between anthropocentrism and ecocentrism. The cumulative effect of these themes on the capacity of the community rights to buy in Scotland to contribute to ecological sustainability will be the focus of the conclusion of this thesis. Chapter 1 introduces and explores these three central themes. It will be argued that global interpretations of sustainable development have tended to adopt an anthropocentric approach within the spectrum of anthropocentrism/ecocentrism, and that this is mirrored in Scotland’s approach to sustainable development. The nature and culture dualism will then be explored as a potential explanation for the anthropocentric focus of both sustainable development and property law. This chapter will conclude that, whilst responsibilities can bridge the gap between anthropocentrism and ecocentrism, the structural effect of Western property law norms resists this, which is problematic for ecological sustainability. Against this background, Chapter 2 is concerned with situating Scotland within these debates. It will assess the concentrated ownership patterns seen today, arguing that an emphasis on individual ownership rights has facilitated this; an example of property law’s structural effects eschewing responsibilities in ownership. These factors have anthropocentric outcomes. This chapter will argue that an increasing focus on responsibilities within land policy in Scotland shows an implicit recognition of the need to move beyond the existing rights paradigm. However, this is stymied by property law’s structural emphasis on rights. Against this background, the chapter will conclude with a brief outline of what the community rights to buy are, their significance, and their adoption of sustainable development, before engaging in a deeper evaluative exercise in Chapter 3. Chapter 3 will assess what kind of sustainable development is being envisaged in the community right to buy legislation, and whether this is suitable for the achievement of ecological sustainability. It will be argued that, whilst showing signs of ecocentrism, given the structural effects of property law in Scotland and the concomitant focus on individual rights the community rights to buy find themselves at the anthropocentric end of the sustainable development spectrum identified in Chapter 1. However, the backdrop of Scottish land policy signifies a will to incorporate responsibilities, as well as rights, into ownership. In this regard, it is argued that the community rights to buy, in their incorporation of sustainable development, signify a form of incremental change when viewed in tandem with other policy in Scotland, which can better integrate ecocentric approaches and which could incite progress towards ecological sustainability

The Impact of Establishing Group Homes on Public Schools Special Education Classes

This study had two purposes: to give a descriptive analysis of group homes, and to determine whether the establishment of group homes has had any impact on public school districts\u27 special education classes in the State of Washington. The factors examined were: who is providing a formal education for the residents; to what extent are group home residents receiving public services

A semantic Grid for molecular science

Proceedings of the 2003 UK e-Science All Hands Meeting, 31st August - 3rd September, Nottingham UKThe properties of molecules have very well defined semantics and allow the creation of a semantic GRID. Markup languages (CML - Chemical Markup Language) and dictionary-based ontologies have been designed to support a wide range of applications, including chemical supply, publication and the safety of compounds. Many properties can be computed by Quantum Mechanical (QM) programs and we have developed a "black-box" system based on XML wrappers for all components. This is installed on a Condor system on which we have computed properties for 250, 000 compounds. The results of this will be available in an OpenData/OpenSource peer-to-peer (P2P) system (WorldWide Molecular Matrix - WWMM)