Factors affecting residential heating energy consumption

Twenty per cent of all energy consumed in New England and ten per cent of all energy consumed in the United States is consumed in home heating. This paper reports on an effort to ascertain the major factors affecting the consumption of home heating oil. Three general classes of factors are analyzed: (1) physical and occupant characteristics (number of rooms, number of occupants, number of stories, amount of insulation, income level, etc.); (2) external (price, shortage awareness, weather); and (3) behavioral and physical changes (change in temperature settings, change in insulation, change in oil burner, etc.). The study is based on four data series: (1) actual monthly home heating oil consumption data on 8000 suburban homeowners in suburban Boston; (2) questionnaire responses from 2000 homeowners on their homes' physical and occupant characteristics, as well as changes in physical and occu- pant behavioral characteristics between 1972 and 1975; (3) monthly weather data; and (4) heating oil price data. The data is associated with the years from 1972 through 1975, a period in which marked price changes, shortages, and behavioral changes occurred, hence providing an opportunity to study the effects of these various events. Three models are central to the study: Model I. A cross-sectional model that depicts consumption per degree-day as a function of physical and occupant characteristics of a home. Model II. A time series regression model that establishes consumption per degree-day as a function of price and consumer awareness of an energy shortage. Model III. A cross-sectional regression model that attempts to explain change in consumption per degree-day from one year to the next as a function of specific conservation actions such as temperature resetting, addition of storm windows, etc. The major findings of each model are as follows: Model I: House size, age of home, family income, and the presence of storm doors and windows are all significant factors in predicting the amount of home oil consumption. Model II: Estimated values of price elasticity with respect to demand for residential heating oil and a measure of 'mnpact of shortage awareness on consumption are determined. This model also demonstrates that there were substantial savings in consumption corresponding to increases in price and shortage awareness from 1972-1975. Model III: he data from the questionnaire indicate that only a few consumers made physical home improvements; however, the data from the oil company indicate that a substantial savings (over 12%) in consumption occurred between the heating seasons 1972/73 and 1973/74. The conclusion from this data indicates that behavioral changes were the major conservation actions taken. Model III indicates that the behavioral change of temperature resetting is significant and the physical change of additional weather stripping and change of burner are significant. Further study is needed, however, to determine those behavioral changes that accounted for the major change in consumption. In addition, this model indicates that different groups within the sample (e.g., by income level, house characteristics) display similar conservation efficiency. In addition to the findings of the models, the paper includes (in Appendix B) a detailed discussion of biases associated with the data. Major conclusions from that discussion are: (1) our sample is representative of suburban homes in the Northern United States; (2) the consumers who responded to the questionnaire were slightly more energy- conscious and responded slightly more dramatically to price increases than the general populace; (3) our residential heating oil prices are representative of those that prevailed in the region; and (4) the heating seasons 1972 through 1975 were warmer than usual. Trends in the data indicate that new homes in the sample have a considerable amount of insulation and the typical single-family house in the sample has storm windows and doors.New England Regional Commission, NEEMIS Project Contract no. 10630776 and the M.I.T./IBM Joint Study Agreemen

Geometry acquisition and grid generation: Recent experiences with complex aircraft configurations

Important issues involved in working with complex geometries are discussed. Approaches taken to address complex geometry issues in the McDonnell Aircraft Computational Grid System and related geometry processing tools are discussed. The efficiency of acquiring a suitable geometry definition, the need to manipulate the geometry, and the time and skill level required to generate the grid while preserving geometric fidelity are discussed

The Low CO Content of the Extremely Metal Poor Galaxy I Zw 18

We present sensitive molecular line observations of the metal-poor blue compact dwarf I Zw 18 obtained with the IRAM Plateau de Bure interferometer. These data constrain the CO J=1-0 luminosity within our 300 pc (FWHM) beam to be L_CO < 1 \times 10^5 K km s^-1 pc^2 (I_CO < 1 K km s^-1), an order of magnitude lower than previous limits. Although I Zw 18 is starbursting, it has a CO luminosity similar to or less than nearby low-mass irregulars (e.g. NGC 1569, the SMC, and NGC 6822). There is less CO in I Zw 18 relative to its B-band luminosity, HI mass, or star formation rate than in spiral or dwarf starburst galaxies (including the nearby dwarf starburst IC 10). Comparing the star formation rate to our CO upper limit reveals that unless molecular gas forms stars much more efficiently in I Zw 18 than in our own galaxy, it must have a very low CO-to-H_2 ratio, \sim 10^-2 times the Galactic value. We detect 3mm continuum emission, presumably due to thermal dust and free-free emission, towards the radio peak.Comment: 5 pages in emulateapj style, accepted by the Astrophysical Journa

The potential impact of Ocean Thermal Energy Conversion (OTEC) on fisheries

The commercial development of ocean thermal energy conversion (OTEC) operations will involve some environmental perturbations for which there is no precedent experience. The pumping of very large volumes of warm surface water and cold deep water and its subsequent discharge will result in the impingement, entrainment, and redistribution of biota. Additional stresses to biota will be caused by biocide usage and temperature depressions. However, the artificial upwelling of nutrients associated with the pumping of cold deep water, and the artificial reef created by an OTEC plant may have positive effects on the local environment. Although more detailed information is needed to assess the net effect of an OTEC operation on fisheries, certain assumptions and calculations are made supporting the conclusion that the potential risk to fisheries is not significant enough to deter the early development of IDEe. It will be necessary to monitor a commercial-scale plant in order to remove many of the remaining uncertainties. (PDF file contains 39 pages.

Vertex-magic Labeling of Trees and Forests

A vertex-magic total labeling of a graph G(V,E) is a one-to-one map λ from E ∪ V onto the integers {1, 2, . . . , |E| + |V|} such that λ(x) + Σ λ(xy) where the sum is over all vertices y adjacent to x, is a constant, independent of the choice of vertex x. In this paper we examine the existence of vertex-magic total labelings of trees and forests. The situation is quite different from the conjectured behavior of edge-magic total labelings of these graphs. We pay special attention to the case of so-called galaxies, forests in which every component tree is a star

The Pathophysiology of Respiratory Failure in Chronic Obstructive Pulmonary Disease

The most important pathophysiologic aspects of chronic and acute obstructive pulmonary disease involve disturbances in ventilation with resulting derangement of gas exchange in the lung. There is considerable variability in the type of abnormality, the time of its appearance in relationship to the history of the disease, and in the progression of the abnormality in blood gases