Judged by the Generations: Baltimore’s Confederate Monuments and the Shaping of Historical Memory

In August 2017, the death of anti-racist protestor Heather Heyer in Charlottesville, Virginia lead to an American reckoning regarding the prominence of Confederate symbols in public spaces. Cities across the country began finding ways to remove the statues of Confederate soldiers and statesmen, and to reexamine other statues dedicated to controversial historical figures. In Baltimore, Maryland, the city’s mayor chose to remove four statues located on public land associated with the Confederacy in an overnight operation. This removal followed two years of debate stirred by tragic events in early summer 2015: the death of Freddie Gray in the custody of the Baltimore Police Department and the Charleston A.M.E. shooting. This paper offers a review of the historical context under which these four memorial statues were erected on public property and an examination of the period from 2015 to 2017 during which the city and its citizens engaged with questions of historical memory in the local setting. This permits an examination of the change in political power dynamics within the city of Baltimore and the nation more broadly, as well as a deeper understanding of how the nation has chosen to reckon with the symbols of a painful past

A 3-field earth-heat-exchange system for a school building in Imola, Italy: Monitoring results

The present study reports the results of a 12-month-long monitoring campaign of an earth-to-air horizontal heat exchanger (EAHX) system in a school complex in Imola, Italy. With more than 2kmof buried pipes, it represents one of the biggest Italian applications of this technology. Considerable differences between inlet and outlet air temperature have been noticed both in winter and in summer. Air temperature and relative humidity have been represented over a psychrometric chart while the energy performance of the system was analysed based on data of sensible heat exchange.The monitored results have been compared with three other cases presented in literature in order to verify the parameter values of different EAHX in various climates and design condition

GIS methodology and case study regarding assessment of the solar potential at territorial level: PV or thermal?

This paper presents a GIS-based methodology for assessing solar photovoltaic (PV) and solar thermal potentials in urban environment. The consideration of spatial and temporal dimensions of energy resource and demand allows, for two different territories of the Geneva region, to determine the suitable building roof areas for solar installations, the solar irradiance on these areas and, finally, the electrical and/or thermal energy potentials related to the demand. Results show that the choice of combining PV and solar thermal for domestic hot water (DHW) is relevant in both territories. Actually, the installation of properly sized solar thermal collectors doesn’t decrease much the solar PV potential, while allowing significant thermal production. However, solar collectors for combined DHW and space heating (SH) require a much larger surface and, therefore, have a more important influence on the PV potential.

Hydrodynamic Interaction between an Accretion Flow and a Strong Wind around a Black Hole

In 2015, space heating and domestic hot water production accounted for around 40% of the Swiss final energy consumption. Reaching the goals of the 2050 energy strategy will require significantly reducing this share despite the growing building stock. Renewables are numerous but subject to spatial–temporal constraints. Territorial planning of energy distribution systems enabling the integration of renewables requires having a spatial–temporal characterization of the energy demand. This paper presents two bottom-up statistical extrapolation models for the estimation of the geo-dependent heat and electricity demand of the Swiss building stock. The heat demand is estimated by means of a statistical bottom-up model applied at the building level. At the municipality level, the electricity load curve is estimated by combining socio-economic indicators with average consumption per activity and/or electric device. This approach also allows to break down the estimated electricity demand according to activity type (e.g., households, various industry, and service activities) and appliance type (e.g., lighting, motor force, fridges). The total estimated aggregated demand is 94 TWh for heat and 58 TWh for electricity, which represent a deviation of 2.9 and 0.5%, respectively compared to the national energy consumption statistics. In addition, comparisons between estimated and measured electric load curves are done to validate the proposed approach. Finally, these models are used to build a geo-referred database of heat and electricity demand for the entire Swiss territory. As an application of the heat demand model, a realistic saving potential is estimated for the existing building stock; this potential could be achieved through by a deep retrofit program. One advantage of the statistical bottom-up model approach is that it allows to simulate a building stock that replicates the diversity of building demand. This point is important in order to correctly account for the mismatch between gross and net energy saving potential, often called performance gap. The impact of this performance gap is substantial since the estimated net saving potential is only half of the gross one

Dynamic interactions between the ground heat exchanger and environments in earth–air tunnel ventilation of buildings

Earth–air tunnel ventilation is an energy efficient method of preheating or cooling of supply air to abuilding. The purposes of this study are to investigate the performance of earth–air heat exchangersunder varying soil and atmosphere conditions and the interactions between the heat exchanger andenvironments. A computer program has been developed for simulation of the thermal performance of anearth–air heat exchanger for preheating and cooling of supply air, taking account of dynamic variationsof climatic, load and soil conditions. The program solves equations for coupled heat and moisture transferin soil with boundary conditions for convection, radiation and evaporation/condensation that vary withthe climate both at the soil top surface and inside the heat exchanger. The importance of dynamic inter-actions between the heat exchanger, soil and atmosphere is illustrated from the comparison of the heattransfer rates through the heat exchanger. The predicted heat transfer rate varies with operating time anddecreases along the passage of air in the heat exchanger. Neglecting the interactions would significantlyover-predict the heat transfer rate and the amount of over-prediction increases with operating time