4,536 research outputs found

    Institutional analysis of solar heating and cooling of housing : summary report

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    Photovoltaics ProjectThis paper is one of a series resulting from institutional analysis of photovoltaic (PV) acceptance. It is the summary report on a study of several residential projects which are part of the DOE-HUD Solar Heating and Cooling Demonstration Program. Other papers in this series look in detail at aspects of the residential institutional arena, and more fully present the cases. The study of solar thermal applications in housing provides useful guidance in structuring programs for PV acceptance in the residential sector. The five cases illustrate one or more institutional forces which influence the acceptance of solar energy in housing. The cases involve residential developments of various sorts, located in Massachusetts, Maryland, Indiana, New Mexico and California. It is determined that each actor in the residential sector has different, and complex motivations for considering, using and continuing to use an innovation such as solar energy. The choices of any given actor are a function of the type, source, density and continuity of information exchanges found within the institutional arena in which he/she operates. Finally, the probability of rate and extent of innovation acceptance will be increased to the degree that the innovation is made comprehensible

    An institutional analysis of the solar heating and cooling residen tial demonstration program

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    The Sunyaev-Zel'dovich temperature of the intracluster medium

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    The relativistic Sunyaev-Zel'dovich (SZ) effect offers a method, independent of X-ray, for measuring the temperature of the intracluster medium (ICM) in the hottest systems. Here, using N-body/hydrodynamic simulations of three galaxy clusters, we compare the two quantities for a non-radiative ICM, and for one that is subject both to radiative cooling and strong energy feedback from galaxies. Our study has yielded two interesting results. Firstly, in all cases, the SZ temperature is hotter than the X-ray temperature and is within ten per cent of the virial temperature of the cluster. Secondly, the mean SZ temperature is less affected by cooling and feedback than the X-ray temperature. Both these results can be explained by the SZ temperature being less sensitive to the distribution of cool gas associated with cluster substructure. A comparison of the SZ and X-ray temperatures (measured for a sample of hot clusters) would therefore yield interesting constraints on the thermodynamic structure of the intracluster gas.Comment: This version accepted for publication in MNRAS following minor revisio

    Home Ranges of Rusty Blackbirds Breeding in Wetlands: How Much Would Buffers from Timber Harvest Protect Habitat?

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    We calculated the home ranges and core areas of 13 adult Rusty Blackbirds (Euphagus carolinus) in Maine to determine (1) the area requirements of breeding adults, (2) whether area requirements of the sexes and of colonial and noncolonial individuals differ, and (3) the proportion of the home range and core area that would be protected by a buffer of no logging of 50–100 m around occupied wetlands. Mean home ranges (37.5 ± 12.6 ha) and core areas (11.1 ± 2.8 ha) were large in comparison to those of other breeding icterids, and adults often foraged in multiple unconnected wetlands. Rusty Blackbirds that were part of a loose colony had home ranges and core areas three times larger than those of pairs that nested solitarily, which we speculate may be due to adults following one other to feed on unpredictable emergences of aquatic insects. Home ranges and core areas included a surprisingly small amount of wetland habitat, only 12% and 19% respectively, but adults often foraged in small wet patches (\u3c16 m2) in otherwise upland habitat. The 75-m buffers around wetlands that we recommended in a concurrent study may help protect the Rusty Blackbird\u27s nesting habitat, but such buffers contained less than half the average home range, suggesting that they may be of only limited benefit as a conservation strategy for protecting foraging habitat

    Toward a theory of institutional analysis

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    This paper provides the basic analytic framework for institutional analysis with particular reference to the acceptance of innovations. A theory of institutions is developed, then assessed in light of various theories of organizations. It is posited that there are six types of institutional entities -- formal and informal organizations, members, persons, collectivities and social orders. Institutions are characterized by function, activity and role. Institutional action consists of exchanges for which the critical datum is information. Such exchanges occur within an institutional arena. Innovation forces institutional action by disrupting existing social meaning. Based on this theory a methodology is developed which enables study of innovation acceptance in various institutional arenas. The methodology involves several steps: (1) Determine study sector and purpose; (2) Preliminary sector exploration; (3) Construct hypothesized institutional arena; (4) Identify perturbation prompter; (5) Devise specific research design; (6) Monitor perturbation; (7) Analyze institutional arena

    Understanding the Success and Failure of Oyster Populations: Periodicities of Perkinsus Marinus, and Oyster Recruitment, Mortality, and Size

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    Ten-year time series (1992 to 2002) of salinity, Dermo disease, and size-class structure and mortality measured for an eastern oyster (Crassostrea virginica) population at a reef in Bay Tambour, Terrebonne Parish, LA, were analyzed using wavelet techniques to determine dominant frequencies and correlations. Along the Gulf Coast of the United States, Dermo disease (caused by Perkinsus marinus) responds to the El Nino-Southern Oscillation (ENSO) climate signal through its response to salinity. During the La Nina portion of ENSO, decreased rainfall leads to an increase in salinity, which triggers a rise in Dermo disease prevalence and intensity, producing increased oyster mortality. Although disease responds to the 4-y periodicity of ENSO and salinity, the oyster population dynamics do not appear to be controlled by disease at this site. A significant 4-y coherency exists between recruitment and salinity, with recruitment being higher during periods of high salinity. \u27Recruit numbers and submarket numbers also exhibit a strong 4-y periodicity. However, a relationship between the recruit time series and the subsequent change in market-size abundance did not exist. The complexity of postsettlement processes and the extended time over which these processes interact decrease the predictability of the recruit-to-market transition. Even the strong pulse of recruits associated with La Nina and its locally elevated salinities did not result in an exceptional abundance of market oysters. Understanding the environmental and biotic factors that favor the production of large oysters is critical because large oysters not only supply the fishery, but, upon their death, contribute the bulk of the shell required for reef sustainability

    Habitat occupancy of Rusty Blackbirds (Euphagus carolinus) breeding in northern New England, USA

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    The Rusty Blackbird (Euphagus carolinus), an uncommon songbird often associated with northern coniferous wetlands, has experienced a precipitous population decline since at least the early 20th century. Here, we provide the first analysis of breeding-habitat occupancy at the wetland scale and make recommendations for streamlined monitoring. We modeled occupancy and detectability as a function of site (i.e. habitat-based) and sampling (i.e. visit-specific) variables collected at 546 wetlands in northern New England, USA. Wetland occupancy (mean 6 SE ¼ 0.07 6 0.02 in randomly selected wetlands, and 0.12 6 0.02 in all wetlands surveyed) was best explained by variables describing Rusty Blackbird foraging habitat (PUDDLES: a proxy for shallow water), nesting habitat (coniferous adjacent uplands), and evidence of beavers. In contrast to Rusty Blackbirds’ selection of pole-stage conifers at the nest-site scale, stand age did not affect occupancy at the wetland scale. It appears that most wetlands in northern coniferous forest landscapes, regardless of stand age, offer dense conifer patches nearby and provide suitable breeding habitat if quality foraging sites (e.g., areas of shallow water) also are available. Detectability (0.29 6 0.04) decreased with increasing wind speed, and decreased about fourfold over the course of the breeding season. Rusty Blackbirds responded to broadcast of conspecific vocalizations by flying toward the observer and perching more often than prior to broadcast, demonstrating that broadcasts can be a useful tool to enhance visual detectability. Given our results, observers can now focus site selection on wetlands and sampling conditions most likely to maximize detections of Rusty Blackbirds

    System change in a public service bureaucracy

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    Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 1973."September 1973."Includes bibliographical references (leaves 285-290).by Thomas Evan Nutt.Ph.D
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