638 research outputs found
What a waste: the generation and disposal of trash imposes costs on society and the environment: should we be doing more?
In 1987, the Mobro 4000 garbage barge from Long Island focused public attention on trash. Have we disposed of the problem?Environmental policy ; Environmental protection
Get me headquarters!
New England has shown continued success in attracting and retaining large corporate headquarters. What is less clear is whether the benefits they bring are as great as in the past.Corporations - Headquarters ; Corporations - New England
Pipe Poiseuille flow of viscously anisotropic, partially molten rock
Laboratory experiments in which synthetic, partially molten rock is subjected
to forced deformation provide a context for testing hypotheses about the
dynamics and rheology of the mantle. Here our hypothesis is that the aggregate
viscosity of partially molten mantle is anisotropic, and that this anisotropy
arises from deviatoric stresses in the rock matrix. We formulate a model of
pipe Poiseuille flow based on theory by Takei and Holtzman [2009a] and Takei
and Katz [2013]. Pipe Poiseuille is a configuration that is accessible to
laboratory experimentation but for which there are no published results. We
analyse the model system through linearised analysis and numerical simulations.
This analysis predicts two modes of melt segregation: migration of melt from
the centre of the pipe toward the wall and localisation of melt into
high-porosity bands that emerge near the wall, at a low angle to the shear
plane. We compare our results to those of Takei and Katz [2013] for plane
Poiseuille flow; we also describe a new approximation of radially varying
anisotropy that improves the self-consistency of models over those of Takei and
Katz [2013]. This study provides a set of baseline, quantitative predictions to
compare with future laboratory experiments on forced pipe Poiseuille flow of
partially molten mantle.Comment: 23 pages, 7 figures. Submitted to Geophysical Journal International
on 25 April 2014. Revised after reviewer comments and resubmitted on 20
August 201
Issues in economics: are lifetime incomes growing more unequal?: looking at new evidence on family income mobility
Since most people judge their well-being by comparison with others, widening inequality of lifetime incomes may threaten our standing as a "land of opportunity."Cost and standard of living ; Income
Women's rise: a work in progress
Recent data show declines in labor force participation for highly educated women, but the causes of these changes are not easy to identify.Women - Employment ; Women executives ; Wages - Women
SNOWPACK CONTROLS ON HYDROLOGIC RESPONSE TO EXTREME RAIN-ON-SNOW EVENTS IN THE NORTHERN SIERRA NEVADA
Continuous, near-real time predictions of winter flooding are critical to balancing the protection of life and property with providing water resources for consumptive use in California’s northern Sierra Nevada. Rain-on-snow (ROS) events are a major cause of floods in the region and are expected to increase as a result of climate change. During ROS, the amount of terrestrial water input (TWI) draining from the snowpack is the major driver of floods and depends on the snowpack's capacity to refreeze liquid water, its transmissivity, and the magnitude of snow melt during the event. The outcome is an interplay between (1) the amount and intensity of precipitation, (2) the antecedent conditions of the snowpack and (3) the potential for incoming energy to melt snow and drain additional water. An incomplete understanding and insufficient measurement of these interacting processes limits the skill of flood prediction in mountain regions. In this study, antecedent snowpack conditions, specifically cold content, density, liquid water content and SWE, are examined to understand how these factors modulate TWI during ROS. Data from three SNOTEL stations, common in the Western U.S., across a 500 m elevation gradient on the eastern side of California’s Sierra Nevada mountains are used as input to a physically-based model that simulates liquid water drainage explicitly (SNOWPACK). Hourly forcing parameters were developed to calibrate and validate the SNOWPACK model to the SNOTEL stations spanning water years 1981-2019 and 149 ROS events. During the 149 historical events, the snowpack mitigated TWI for 80% of events, 13% had no mitigation, and 7% had conditions for active melt. Mean TWI increased 32% from the lowest elevation (58 mm of water) to the highest elevation (85 mm of water). As expected, the amount of TWI depends on total rainfall, however, that events with TWI/rain ratios>1.0 produce the largest event streamflows. When antecedent conditions were varied in reasonable ways, total TWI response varies 46% on average across eight extreme events. A key result is that snowpack cold content explains the majority of TWI variability. Riper snowpacks generated the highest TWI values for most events, with a 1 MJ decrease in cold content corresponding to 0.74 more TWI. Our results highlight the importance of cold content in TWI response across realistic antecedent conditions. Cold content is rarely measured and effectively not included in operational flood forecast models. As ROS becomes increasingly frequent in a warming climate, enhanced observations of cold content and modeling could have important implications for improved flood forecasting
Opportunities for information sharing: case studies
Personal information provided to government and non-government service providers is highly sensitive. Appropriate collection, management and storage of personal information are critical elements to citizen trust in the public sector. However, misconceptions about the frameworks governing sharing personal information can impact on the coordination of services, case management and policy development.
The NSW Department of Premier & Cabinet engaged the Social Policy Research Centre to develop three case studies that identified the challenges to sharing information appropriately, and the opportunities for better personal information sharing between government agencies and non-government organisations. Improved sharing of personal information in these areas can support more effective policy development, leading to improved service delivery performance and coordination.
The Social Policy Research Centre identified the legislative and policy framework for each case study, conducted qualitative research on the interpretation of this framework, and developed three case study reports
Urban and architectural design perspectives on the renovation of Revere Beach, Massachusetts
Thesis (M. Arch.)--Massachusetts Institute of Technology, Dept. of Architecture, 1985.MICROFICHE COPY AVAILABLE IN ARCHIVES AND ROTCH.Includes bibliographical references (leaf 56).Through analyses and design studies, this thesis articulates qualities of environment and architecture that affect the redevelopment of an urban beach. Looking at Boston, Massachusetts' Revere Beach, it examines the impact of shape, location, and environmental, social and economic background on the form and program of future building along the beach edge. The thesis draws together two issues, use and form, in looking at large issues of any redevelopment: distinguishing valid public claims from private, residential from commercial, local from regional, pedestrian from automobile and mass transit. wealthy from poor. It raises questions about the nature of recreation and work, in association with other civic roles for the beach. The study analyzes physical form from the perspective of various combinations of use and vice versa: programs from the standpoint of form. The work discusses architecture and urban design in terms that consider the new development's role in orienting people within their environment; it tries to define what that means specifically at Revere. From regional to local to building to material dimension, the paper questions what suggests qualities of "beach-ness", particularly of a Revere Beach sort. Finally, preliminary sketches and notes for a sea edge design include provisions for both public and private uses, with a character that expresses the beach's seasonal nature as well as providing protection and comfort throughout the year. The design proposal differentiates between various program elements, and seeks their appropriate placement within a new development. Public services include bath houses, information centers, parking systems, and a pedestrian framework of promenades, amphitheaters, courtyards, and access ways. The commercial activity, public to some extent, includes theatres, restaurants, health clinics, schools and athletic facilities, as well as sunning, swimming, souvenir-related shops. Questions of ownership and management are briefly addressed. The project also examines possibilities for including in the design floating sew age treatment facilities and land-based win d generators, as ways to correlate recreational facilities with a public understanding of the urban infrastructure.by Jane Sarah Katz.M.Arch
Monument Square, Charlestown : seeking timelessness in a temporal world
Thesis (M. Arch.)--Massachusetts Institute of Technology, Dept. of Architecture, 1983.MICROFICHE COPY AVAILABLE IN ARCHIVES AND ROTCHIncludes bibliographical references (leaves 104-106).The Bunker Hill Monument, a 220-foot high granite obelisk built from 1825-1842, stands on a grassy mound known as Monument Square. Today the situation of the monument incites curiosity, standing as it does amidst brick and wooden rowhouses in a residential area of Charlestown, Mass. The Bunker Hill Monument Association (BHMA), builder of the obelisk, was also responsible for the planning and development of 15 acres surrounding it. These memorial builders - lawyers, doctors, and businessmen - became investors in America's first commercial railroad, part of the network moving the granite blocks. They also became real estate developers - to help pay for the expensive monument, the BHMA sold part of the "sacred" battlefield as houselots. Many factors, some familiar today and others quite remote, shaped the monument and its surround: technological innovation and capitalism, land-use economics, and at least one special-interest group - the freemasons. Through historical research and visual analysis, this thesis studies these factors as part of the process through which the product, Monument Square, emerged. The construction time period of the monument coincided with a fundamental change in Charlestown housing: the transition from semi-rural detached homes to the rowhouse. The houses of Monument Square, built on the land sold by the BHMA, afford the opportunity to study communal agreement as to the form of this newly emerging urbanity. This agreement is sometimes explicit, as in the innovative deed restrictions, but also implicit in aspects of house design not covered by the restrictions. The durable monument and its open square have helped to maintain the robustness of the area, which escaped the widespread clearance which occurred in other parts of Charlestown during the 1960's.by Ellen Jane Katz.M.Arch
- …