MAT-734: INCREASING THE DURABILITY AND RESILIENCE OF TALL BUILDINGS WITH PRECAST CONCRETE ENCLOSURE SYSTEMS

In this paper precast concrete wall systems are compared to curtain wall and window wall systems in terms of durability and disaster resilience of multi-story buildings. Window wall systems are currently the enclosure system of choice for tall residential buildings in most parts of North America. Precast concrete wall systems can be expected to last the lifetime of a building with routine seal replacement. These are highly durable systems. Windows within precast concrete wall systems will require replacement in 25-35 years but represent a limited portion of the wall area and hence are less costly and have less impact on building use interruption. The impact of façade choice on passive survivability and security are also considered. Maintaining livable temperatures in a space in Toronto, Ontario (a city with a climate similar to many Northern U.S. cities) during a power outage is shown to mostly depend on having little heat loss, reducing solar gains, and provision of thermal mass. A whole wall metric is also introduced which combines various vision and non-vision wall system heat loss components. A similar metric for solar gain is introduced. The most significant factor affecting this heat loss and solar gain (and thereby affecting thermal resilience) is to avoid high Window to Wall Ratios (WWR). This will apply for most wall systems but is most significant for systems like precast concrete where there is minimal thermal bridging through the insulation. In terms of security, precast concrete walls will protect occupants from projectiles and endure little damage during disasters. These impacts make precast concrete wall systems significantly more disaster resilient

Environmental impact assessment of commercial aircraft operations in the United States

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2009.Cataloged from PDF version of thesis.Includes bibliographical references (p. 313-365).The objective of this thesis was to evaluate the environmental trade-offs inherent in multi-criteria objectives of an integrated environmental policy. A probabilistic multi-attribute impact pathway analysis (MAIPA) was formulated to assess the environmental damages of US commercial aircraft operations from 1991-2003. The initial contribution of this work was demonstrating the feasibility of, and identifying requirements for, the FAA Aviation-environmental Portfolio Management Tool (APMT), an integrated assessment capability for US regulatory decision-making. Non-aircraft sources have been found to dictate marginal emissions costs. The implication is that aviation emissions reductions influence neither the magnitudes nor trends in per-unit marginal damages. In contrast, noise mitigation is the dominant influence on the value of per-unit marginal damages. Trends in sum damages were found to depend on the growth rates of air transport relative to other source emissions. Growth in air transport emissions outpaced non-aircraft sources from 1991-2003. Because growth in marginal costs is nonlinear over this period, aviation emissions damages grow faster than inventories. Applying methods similar to MAIPA to estimate damages for future scenarios suggests that stemming climate impacts is fast becoming the priority. A reassessment of the environmental benefits derived from mandated phase-outs of noisy aircraft during the 1990's has been carried out. Previous studies estimated a -80% reduction in population exposure. In contrast, the reassessment estimates a ~2% reduction, providing benefits 17-20 times lower than published estimates of abatement costs.(cont.) The primary environmental benefit of the noise phase-outs was found to be related to reductions in particulate matter inventories. One way to avoid trade-off inefficiencies is to identify options that bundle benefits. This action provides such an example, where the phase-outs led to reductions in both noise and air quality emissions. Other contributions in the thesis include the following: a treatment of air transport particulate matter emissions, environmental fate, and health impacts of particulate matter; identification that the major source of reducible uncertainty in emissions damages stems from the assumed extent of ozone and particulate matter production in the engine exhaust plume; and quantification of the environmental tradeoffs in decisions specifying aircraft performance for the technology in the US commercial fleet from 1991-2003.by Stephen P. Lukachko.Ph.D

Wyandotte Neighborhood Stabilization Program: Retrofit of Two Homes

The Wyandotte NSP2 project aims to build 20 new houses and retrofit 20 existing houses in Wyandotte, MI. This report will detail the retrofit of 2 existing houses in the program. Wyandotte is part of a Michigan State Housing Development Authority-led consortium that is funded by HUD under the NSP2 program. The City of Wyandotte has also been awarded DOE EE&CBG funds that are being used to develop a district GSHP system to service the project. This draft report examines the energy efficiency recommendations for retrofit construction at these homes. The report will be of interest to anyone planning an affordable, high performance retrofit of an existing home in a Cold Climate zone. Information from this report will also be useful to retrofit or weatherization program staff as some of the proposed retrofit solutions will apply to a wide range of projects. Preliminary results from the first complete house suggest that the technology package employed (which includes spray foam insulation and insulating sheathing) does meet the specific whole house water, air, and thermal control requirements, as well as, the project's affordability goals. Monitoring of the GSHP system has been recommended and analysis of this information is not yet available

Strategy Guideline. Advanced Construction Documentation Recommendations for High Performance Homes

As whole house energy efficiency increases, new houses become less like conventional houses that were built in the past. New materials and new systems require greater coordination and communication between industry stakeholders. The Guideline for Construction Documents for High Performance Housing provides advice to address this need. The reader will be presented with four changes that are recommended to achieve improvements in energy efficiency, durability and health in Building America houses: create coordination drawings, improve specifications, improve detail drawings, and review drawings and prepare a Quality Control Plan

Relationships Between Working Alliance and Outcomes in Group Therapy for People Diagnosed with Schizophrenia

Working alliance (WA) is an important predictor of treatment outcomes in therapy. Forming a strong WA can be challenging with people diagnosed with schizophrenia, and differences between client-rated and clinician-rated WA have been found in this population. This project examined WA in people diagnosed with schizophrenia who completed a skills training and attention shaping group intervention. Paired samples t-tests revealed differences between client and clinician ratings on the Working Alliance Inventory Short Form (WAI-S). Clinician-rated WAI-S scores were related to symptom severity, cognitive functioning, and attention during group sessions. Yet, the primary hypothesis was not supported as WAI-S scores were unrelated to clients’ treatment response. Clinician-rated WAI-S was found to partially mediate the relationship between negative symptoms and overall attention. Client-rated WAI-S scores were associated with client measures of self-efficacy and mastery. Results reinforce the importance of working alliance in the treatment of those diagnosed with schizophrenia and indicate clinical and functional factors that may influence the quality of WA

Heterogeneous reactions in aircraft gas turbine engines

[1] One-dimensional flow models and unity probability heterogeneous rate parameters are used to estimate the maximum effect of heterogeneous reactions on trace species evolution in aircraft gas turbines. The analysis includes reactions on soot particulates and turbine/nozzle material surfaces. Results for a representative advanced subsonic engine indicate the net change in reactant mixing ratios due to heterogeneous reactions is <10 À6 for O 2 , CO 2 , and H 2 O, and <10 À10 for minor combustion products such as SO 2 and NO 2 . The change in the mixing ratios relative to the initial values is < 0.01%. Since these estimates are based on heterogeneous reaction probabilities of unity, the actual changes will be even lower. Thus, heterogeneous chemistry within the engine cannot explain the high conversion of SO 2 to SO 3 whicsome wake models require to explain the observed levels of vola tile aerosols. Furthermore, turbine heterogeneous processes will not effect exhaust NO x or NO y levels

Laser-Spectroscopic Investigation of OH-Radical Concentrations in the Exhaust Plane of Jet Engines

Hydroxyl radical (OH) emissions are relevant for oxidation reactions in the post flame chemistry of exhaust gases emitted from jet engines. No direct measurements of OH concentrations are available to date due to the low abundance and the short lifetime of this radical species. The first application of a combined technique based on Raman scattering and laser_induced fluorescence (LIF) spectrometry is presented here for measurements in the exhaust gases of a commercial jet engine operated in a test rig. From the measurements, upper limits for OH concentrations in the exit plane were determined in the range of 90 ppbv for take off and 80 ppbv for ap_idle. The values are significantly below the predictions of model calculations based on HONO and HNO3 in_flight concentration measurements presented recently. Possibilities for further increase of the detection sensitivity for OH are discussed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/86750/1/Sick34.pd

Investigating the influence of African American and African Caribbean race on primary care doctors' decision making about depression

This paper explores differences in how primary care doctors process the clinical presentation of depression by African American and African-Caribbean patients compared with white patients in the US and the UK. The aim is to gain a better understanding of possible pathways by which racial disparities arise in depression care. One hundred and eight doctors described their thought processes after viewing video recorded simulated patients presenting with identical symptoms strongly suggestive of depression. These descriptions were analysed using the CliniClass system, which captures information about micro-components of clinical decision making and permits a systematic, structured and detailed analysis of how doctors arrive at diagnostic, intervention and management decisions. Video recordings of actors portraying black (both African American and African-Caribbean) and white (both White American and White British) male and female patients (aged 55 years and 75 years) were presented to doctors randomly selected from the Massachusetts Medical Society list and from Surrey/South West London and West Midlands National Health Service lists, stratified by country (US v.UK), gender, and years of clinical experience (less v. very experienced). Findings demonstrated little evidence of bias affecting doctors' decision making processes, with the exception of less attention being paid to the potential outcomes associated with different treatment options for African American compared with White American patients in the US. Instead, findings suggest greater clinical uncertainty in diagnosing depression amongst black compared with white patients, particularly in the UK. This was evident in more potential diagnoses. There was also a tendency for doctors in both countries to focus more on black patients' physical rather than psychological symptoms and to identify endocrine problems, most often diabetes, as a presenting complaint for them. This suggests that doctors in both countries have a less well developed mental model of depression for black compared with white patients

Research on the science and politics of the atmospheric effects of aviation debate

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1997.Includes bibliographical references (p. 431-442).by Stephen P. Lukachko.M.S

Wyandotte Neighborhood Stabilization Program: Retrofit of Two Homes

The Wyandotte NSP2 project aims to build 20 new houses and retrofit 20 existing houses in Wyandotte, MI. This report will detail the retrofit of 2 existing houses in the program. Wyandotte is part of a Michigan State Housing Development Authority-led consortium that is funded by HUD under the NSP2 program. The City of Wyandotte has also been awarded DOE EE&CBG funds that are being used to develop a district GSHP system to service the project. This draft report examines the energy efficiency recommendations for retrofit construction at these homes. The report will be of interest to anyone planning an affordable, high performance retrofit of an existing home in a Cold Climate zone. Information from this report will also be useful to retrofit or weatherization program staff as some of the proposed retrofit solutions will apply to a wide range of projects. Preliminary results from the first complete house suggest that the technology package employed (which includes spray foam insulation and insulating sheathing) does meet the specific whole house water, air, and thermal control requirements, as well as, the project's affordability goals. Monitoring of the GSHP system has been recommended and analysis of this information is not yet available