760 research outputs found
Girls and Gangs: A Decade on From the Firmin Report and What Has Changed?
Presenting data from the first phase of a U.K.-based 5-year mixed-methods study, we restart a decade-long conversation into Girls and Gangs and Violence Against Women and Girls (VAWG). The relationship between the two is not mutually exclusive and coupled with the recent optics surrounding youth violence and gendered violence, we discuss how the needs of women are being somewhat hindered as a result of U.K. governmental vacillation. We therefore consider the serious impact of VAWG and the concomitancy with youth violence/gangs. By drawing on contemporary feminist criminological theorizing, we aim to galvanize governmental responses to prioritize the needs of women at a time when policymakers are arguably poised to listen
Commissioning Existing Buildings: A Program Perspective
Since September 2002, the Oakland Energy
Partnership's Large Commercial Building Tune-Up
Program has recruited managers and operators of
existing large commercial buildings in the City of
Oakland for program participation. The Tune-Up
Program is an aggressive effort to obtain 16.7 GWh
in energy savings in over 10 Mft2 in office,
institutional, healthcare, hotel, educational, and
retail buildings. Sponsored under the California
Public Utility Commission's 2002 Local Program
initiative, the Tune-Up program provides retro
commissioning (r-Cx) teams to help building
owners and operators thoroughly investigate the
operations and performance of their existing
building systems, identify measures that improve
energy performance, assist with measure
installation and verification, and provide
documentation to operators on optimum system
performance.
Great importance has been placed on the initial
assessment of each building, in order to answer
important questions from the program's and
owner's perspectives. These issues include:
condition of building's systems and equipment,
amount of savings potential, skill sets of r-Cx
teams, assurance that measures will be installed,
persistence of installed measures.
This paper describes how the program recruits
buildings, assesses the potential for savings, and
assigns engineering teams. The type and size of
buildings, their HVAC and lighting configurations,
common r-Cx measures found, and their savings
are described Results for each building are
described, and the program's cost-effectiveness is
reviewed. Currently, six buildings totaling 2.8
million square feet have been recruited, for an
expected savings of approximately 2.4 GWh. This
is 14% toward our program goal
Predicting On-axis Rotorcraft Dynamic Responses Using Machine Learning Techniques
Physical-law-based models are widely utilized in the aerospace industry. One such use is to provide flight dynamics models for use in flight simulators. For human-in-the-loop use, such simulators must run in real-time. Owing to the complex physics of rotorcraft flight, to meet this real-time requirement, simplifications to the underlying physics sometimes have to be applied to the model, leading to errors in the model's predictions of the real vehicle's response. This study investigated whether a machine-learning technique could be employed to provide rotorcraft dynamic response predictions. Machine learning was facilitated using a Gaussian process (GP) nonlinear autoregressive model, which predicted the on-axis pitch rate, roll rate, yaw rate, and heave responses of a Bo105 rotorcraft. A variational sparse GP model was then developed to reduce the computational cost of implementing the approach on large datasets. It was found that both of the GP models were able to provide accurate on-axis response predictions, particularly when the model input contained all four control inceptors and one lagged on-axis response term. The predictions made showed improvement compared to a corresponding physics-based model. The reduction of training data to one-third (rotational axes) or one-half (heave axis) resulted in only minor degradation of the sparse GP model predictions. response predictions. Machine learning was facilitated using a Gaussian process (GP) nonlinear autoregressive model, which predicted the on-axis pitch rate, roll rate, yaw rate, and heave responses of a Bo105 rotorcraft. A variational sparse GP model was then developed to reduce the computational cost of implementing the approach on large datasets. It was found that both of the GP models were able to provide accurate on-axis response predictions, particularly when the model input contained all four control inceptors and one lagged on-axis response term. The predictions made showed improvement compared to a corresponding physics-based model. The reduction of training data to one-third (rotational axes) or one-half (heave axis) resulted in only minor degradation of the sparse GP model predictions.</jats:p
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Energy impacts of attic duct retrofits in Sacramento houses
Inefficiencies in air distribution systems have been identified as a major source of energy loss in US sunbelt homes. Research indicates that approximately 30--40% of the thermal energy delivered to the ducts passing through unconditioned spaces is lost through air leakage and conduction through the duct walls. Field experiments over the past several years have well documented the expected levels of air leakage and the extent to which that leakage can be reduced by retrofit. Energy savings have been documented to a more limited extent, based upon a few field studies and simulation model results. Simulations have also indicated energy loss through ducts during the off cycle caused by thermosiphon-induced flows, however this effect had not been confirmed experimentally. A field study has been initiated to separately measure the impacts of combined duct leak sealing and insulation retrofits, and to optimize a retrofit protocol for utility DSM programs. This paper describes preliminary results from 6 winter and 5 summer season houses. These retrofits cut overall duct leakage area approximately 64%, which translated to a reduction in envelope ELA of approximately 14%. Wrapping ducts and plenums with R-6 insulation translated to a reduction in average flow-weighted conduction losses of 33%. These experiments also confirmed the appropriateness of using duct ELA and operating pressures to estimate leakage flows for the population, but indicated significant variations between these estimates and measured flows on a house by house basis. In addition, these experiments provided a confirmation of the predicted thermosiphon flows, both under winter and summer conditions. Finally, average material costs were approximately 20% of the total retrofit costs, and estimates of labor required for retrofits based upon these experiments were: 0.04 person-hrs/cm{sup 2} of duct sealed and 0.21 person-hrs/m{sup 2} of duct insulated
Prediction and Simulator Verification of Roll/Lateral Adverse Aeroservoelastic Rotorcraft–Pilot Couplings
The involuntary interaction of a pilot with an aircraft can be described as pilot-assisted oscillations. Such
phenomena are usually only addressed late in the design process when they manifest themselves during ground/flight
testing. Methods to be able to predict such phenomena as early as possible are therefore useful. This work describes a
technique to predict the adverse aeroservoelastic rotorcraft–pilot couplings, specifically between a rotorcraft’s roll
motion and the resultant involuntary pilot lateral cyclic motion. By coupling linear vehicle aeroservoelastic models
and experimentally identified pilot biodynamic models, pilot-assisted oscillations and no-pilot-assisted oscillation
conditions have been numerically predicted for a soft-in-plane hingeless helicopter with a lightly damped regressive
lead–lag mode that strongly interacts with the roll modeat a frequency within the biodynamic band of the pilots. These
predictions have then been verified using real-time flight-simulation experiments. The absence of any similar adverse
couplings experienced while using only rigid-body models in the flight simulator verified that the observed
phenomena were indeed aeroelastic in nature. The excellent agreement between the numerical predictions and the
observed experimental results indicates that the techniques developed in this paper can be used to highlight the
proneness of new or existing designs to pilot-assisted oscillation
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Field measurement of the interactions between heat pumps and attic duct systems in residential buildings
Research efforts to improve residential heat-pump performance have tended to focus on laboratory and theoretical studies of the machine itself, with some limited field research having been focused on in-situ performance and installation issues. One issue that has received surprisingly little attention is the interaction between the heat pump and the duct system to which it is connected. This paper presents the results of a field study that addresses this interaction. Field performance measurements before and after sealing and insulating the duct systems were made on three heat pumps. From the pre-retrofit data it was found that reductions in heat-pump capacity due to low outdoor temperatures and/or coil frosting are accompanied by lower duct-system energy delivery efficiencies. The conduction loss reductions, and thus the delivery temperature improvements, due to adding duct insulation were found to vary widely depending on the length of the particular duct section, the thermal mass of that duct section, and the cycling characteristics of the heat-pump. In addition, it was found that the use of strip-heat back-up decreased after the retrofits, and that heat-pump cycling increased dramatically after the retrofits, which respectively increase and decrease savings due to the retrofits. Finally, normalized energy use for the three systems which were operated consistently pre- and post-retrofit showed an average reduction of 19% after retrofit, which corresponds to a chance in overall distribution-system efficiency of 24%
Association between differential gene expression and body mass index among endometrial cancers from The Cancer Genome Atlas Project
The Cancer Genome Atlas (TCGA) identified four integrated clusters for endometrial cancer (EC): POLE, MSI, CNL and CNH. We evaluated differences in gene expression profiles of obese and non-obese women with EC and examined the association of body mass index (BMI) within the clusters identified in TCGA
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