246 research outputs found

    Energy Analysis of the Texas Capitol Restoration

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    This paper presents the methodology and results of a detailed energy analysis of the Texas Capitol Restoration. The purpose of this analysis was two-fold: 1) to determine the projected energy cost savings of a series of design alternatives for the Capitol Restoration, and 2) to calibrate the simulation model of the Capitol in its prerestored condition (in September 1991) using monitored energy use data from the Texas LoanSTAR program. The Capitol in its proposed restored condition was simulated using the DOE-2 building energy analysis computer program with long-term Austin weather data to project the annual energy use, peak electric demand, and annual energy cost. Then a series of 13 energy efficient design altematives was simulated. The results were compared to those of the base case to determine the projected annual energy and energy cost savings for each measure, and for combinations of several of the measures. Finally, the paper documents the calibration of the DOE-2 model for the Capitol in its prerestored condition, using monitored hourly whole-building electric data (excluding heating and cooling energy)

    Determination of Retrofit Savings Using a Calibrated Building Energy Simulation Model

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    This paper presents the development of a methodology to determine retrofit energy savings in buildings when few measured preretrofit data are available. Calibration of the DOE-2 building energy analysis computer program for a 250,000 ft2 building at The University of Texas at Austin, using hourly data for a two-month preretrofit period, is detailed.. The process begins with the identification of the DOE-2 input parameters having the greatest uncertainty. Field measurements then determine those uncertain parameters that have a significant impact on total energy use. Finally, the few remaining parameters are systematically adjusted to match the preretrofit data. Using the calibrated model run for the postretrofit period, energy savings were calculated for whole-building electric, cooling, and heating energy use, and were compared with savings calculated using a regression model developed under the LoanSTAR program. Finally, to validate the model, postretrofit DOE-2 results were compared with measured postretrofit data for a seven-month period

    Improved Near Surface Heavy Impurity Detection by a Novel Charged Particle Energy Filter Technique

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    As the typical feature size of silicon integrated circuits, such as in VLSI technology, has become smaller, the surface cleanliness of silicon wafers has become more important. Hence, detection of trace impurities introduced during the processing steps is essential. A novel technique, consisting of a ``Charged Particle Energy Filter (CPEF)`` used in the path of the scattered helium ions in the conventional Rutherford Backscattering geometry, is proposed and its merits and limitations are discussed. In this technique, an electric field is applied across a pair of plates placed before the detector so that backscattered particles of only a selected energy range go through slits to strike the detector. This can be used to filter out particles from the lighter substrate atoms and thus reduce pulse pileup in the region of the impurity signal. The feasibility of this scheme was studied with silicon wafers implanted with 1{times}10{sup 14} and 1{times}10{sup 13} {sup 54}Fe/cm{sup 2} at an energy of 35 keV, and a 0.5 MeV He{sup +} analysis beam. It was found that the backscattered ion signals from the Si atoms can be reduced by more than three orders of magnitude. This suggests the detection limit for contaminants can be improved by at least two orders of magnitude compared to the conventional Rutherford Backscattering technique. This technique can be incorporated in 200--300 kV ion implanters for monitoring of surface contaminants in samples prior to implantation

    Modeling resilience and sustainability in ancient agricultural systems

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    The reasons why people adopt unsustainable agricultural practices, and the ultimate environmental implications of those practices, remain incompletely understood in the present world. Archaeology, however, offers unique datasets on coincident cultural and ecological change, and their social and environmental effects. This article applies concepts derived from ecological resilience thinking to assess the sustainability of agricultural practices as a result of long-term interactions between political, economic, and environmental systems. Using the urban center of Gordion, in central Turkey, as a case study, it is possible to identify mismatched social and ecological processes on temporal, spatial, and organizational scales, which help to resolve thresholds of resilience. Results of this analysis implicate temporal and spatial mismatches as a cause for local environmental degradation, and increasing extralocal economic pressures as an ultimate cause for the adoption of unsustainable land-use practices. This analysis suggests that a research approach that integrates environmental archaeology with a resilience perspective has considerable potential for explicating regional patterns of agricultural change and environmental degradation in the past

    Loss of the interferon-γ-inducible regulatory immunity-related GTPase (IRG), Irgm1, causes activation of effector IRG proteins on lysosomes, damaging lysosomal function and predicting the dramatic susceptibility of Irgm1-deficient mice to infection

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    The interferon-γ (IFN-γ)-inducible immunity-related GTPase (IRG), Irgm1, plays an essential role in restraining activation of the IRG pathogen resistance system. However, the loss of Irgm1 in mice also causes a dramatic but unexplained susceptibility phenotype upon infection with a variety of pathogens, including many not normally controlled by the IRG system. This phenotype is associated with lymphopenia, hemopoietic collapse, and death of the mouse.Deutscher Akademischer Austausch Dienst (DAAD); International Graduate School in Development Health and Disease (IGS-DHD); Deutsche For-schungsgemeinschaft (SFBs 635, 670, 680); Max-Planck-Gesellschaft (Max Planck Fellowship)

    ‘Sons of athelings given to the earth’: Infant Mortality within Anglo-Saxon Mortuary Geography

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    FOR 20 OR MORE YEARS early Anglo-Saxon archaeologists have believed children are underrepresented in the cemetery evidence. They conclude that excavation misses small bones, that previous attitudes to reporting overlook the very young, or that infants and children were buried elsewhere. This is all well and good, but we must be careful of oversimplifying compound social and cultural responses to childhood and infant mortality. Previous approaches have offered methodological quandaries in the face of this under-representation. However, proportionally more infants were placed in large cemeteries and sometimes in specific zones. This trend is statistically significant and is therefore unlikely to result entirely from preservation or excavation problems. Early medieval cemeteries were part of regional mortuary geographies and provided places to stage events that promoted social cohesion across kinship systems extending over tribal territories. This paper argues that patterns in early Anglo-Saxon infant burial were the result of female mobility. Many women probably travelled locally to marry in a union which reinforced existing social networks. For an expectant mother, however, the safest place to give birth was with experience women in her maternal home. Infant identities were affected by personal and legal association with their mother’s parental kindred, so when an infant died in childbirth or months and years later, it was their mother’s identity which dictated burial location. As a result, cemeteries central to tribal identities became places to bury the sons and daughters of a regional tribal aristocracy
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