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This paper investigates the cyber resiliency of future power systems with high penetration of distributed energy resources using advanced distributed and (or) hierarchical control architectures. Specifically, we simulate cyberattacks on three prototypical use cases, and we identify attack scenarios that are the most damaging to the overall system performance. We show that these attacks can have a significant impact on grid operation. Results provide additional insights into the robustness of the system to the most common cyberattacks. • This paper delves into the realm of cyber-resiliency, examining its implications across three distinct use cases encompassing distributed, distributed-hierarchical, and hierarchical control architectures. • Through exhaustive numerical simulations, we discern and highlight the precise signals within the system that exhibit heightened susceptibility to cybersecurity attacks. • The results obtained from our analysis offer valuable insights into the robustness of these systems, shedding light on their ability to withstand potential cybersecurity threats. [ABSTRACT FROM AUTHOR]

In the face of a changing climate, a growing number of construction firms are adopting carbon reduction targets on individual projects and across their portfolios. In the wake of the Paris Agreement, some firms are seeking a means of aligning their targets with sectoral, national and international mitigation commitments. There are numerous ways by which such an alignment can be achieved, each requiring different assumptions. Using data from the UK construction industry, this paper reviews current company commitments and progress in carbon mitigation; analyses the unique challenges in aligning construction targets, and presents a series of possible sectoral decarbonisation trajectories. The results highlight the disparity between current company targets and the range of possible trajectories. It is clear that a cross-industry dialogue is urgently required to establish an appropriate response that delivers both a widely-accepted target trajectory and a plan for its delivery. This paper is intended to stimulate and support this necessary debate by illustrating the impact of different methodological assumptions and highlighting the critical features of an appropriate response. [ABSTRACT FROM AUTHOR]

Climatic conditions strongly affect the energy performance of buildings, and due to the synergy between global climate change and the Urban Heat Island (UHI) effect, the climatic conditions inside and outside the city are highly different. However, weather data collected at airports are commonly used for building energy simulations and these data do not take into account real temperature distribution in cities. Many studies in the literature address the topic but mostly considering only a couple of urban and non-urban stations. In this paper, the urban climate in Rome, Italy, is analysed after monitoring of the air temperature and relative humidity in four selected neighbourhoods and one reference station from October 2014 until September 2017. Rome is characterised by a composite urban pattern and high variability of building types, of which the four selected areas are representative. The heating degree days decrease up to 18% and cooling degree days increase up to 157% in the urban area with respect to the rural reference and the area most affected by the UHI is the city centre. The UHI is more intense in summer than in winter (average increase between 0.7 °C and 1 °C); while the diurnal and nocturnal UHI depends on the season and the neighbourhood. Then, the energy performance of a representative apartment block and a typical office building was computed using the measured data. Regarding the predicted energy performance, comparing the four urban sites and the reference site, the UHI causes a reduction of heating consumption up to 21% in residential building and 18% in the office building. An increase of cooling consumption up to 74% is instead computed for the residential building and up to 53% for the office building. [ABSTRACT FROM AUTHOR]

This paper presents a computational scheme for simulating debris-flow impact pressures on buildings in urban areas. The debris flow mobility is described using depth-averaged mass and momentum equations considering the erosion and deposition processes and changing solid concentrations. The total impact pressure consists of a dynamic impact pressure from the moving debris flow mixture and a static pressure from the deposited debris material. A target analysis area on Hong Kong Island, including a large number of buildings in that area, is characterized precisely using a three-dimensional high-resolution digital elevation model, and discretized into a grid of 5 m square cells with different bed material parameters. Using the model, the flow patterns of a large debris flow around nearly 20 buildings along the flow path and the impact pressures against the facades of these buildings are simulated. The buildings increase the flow depth and flow velocity as the debris tends to run up and deposit in front of the buildings and the flow path tends to be narrowed due to building blockage. The impact pressures are high on the building facades that face the main traversing path of the debris flow. Deposition of debris in front of the buildings increases the impact pressure. [ABSTRACT FROM AUTHOR]

Abstract: There has been a great deal of work undertaken on the modelling and protection of the structure of buildings to explosive blast, fragment and missile penetration. Buildings and tunnels present interesting challenges because of the different energy release characteristics of modern explosives and gaseous mixtures. The paper describes how by combining modelling capabilities in blast–structure interaction with vulnerability models a capability is formed that has a wide range of potential uses, which links the many stages of response planning to an attack or more general emergency. From designing survivable infrastructures and planning protective measures, through training of staff and responders to handling of actual events, the concept provides a comprehensive approach to the whole spectrum of building and infrastructure survivability assessment issues for a wide range of environments. The paper describes its application to buildings and other related infrastructure. [ABSTRACT FROM AUTHOR]

This paper reports on a project to construct and test an instrument that, for the first time, enables the accurate measurement of convective heat transfer coefficients (chtcs) in real buildings. Computer simulation models for the prediction of heat and airflow in buildings commonly rely on such empirically derived values. However, there are large uncertainties associated with their evaluation and use.The instrument described in this paper has been tested by measuring the chtcs on a heated plate mounted in a test room. The experimental work reported here was made up of two parts:The results are encouraging. Comparisons of the chtcs determined by the new instrument and the chtcs determined by the ‘traditional’ heated plate method have shown close agreement. It seems that the new instrument has great potential for use in real buildings. [Copyright &y& Elsevier]

Nowadays, energy simulation in many respects assists researchers and engineers in the design phase, as well as in the buildings operational phase. Reliability of the integrated simulation model and the knowledge and experience of the user are the cornerstones of good quality simulation prediction result. This study was preceded by a detailed and long-term experimental analysis of the building with a double-skin ventilated façade [10] . The paper presents results of the measurement, fine-tuning process and validation of the numerical simulation model. The simulation software tool, EnergyPlus in combination with Airflow Network Algorithm algorithm was used for the cavity air temperature and velocity prediction. When the model was verified, the criterion of eligibility were defined with the recommended statistical indicators. In order to achieve the better assessment, the validation process was done trifold: for winter, transitional and summer season. Overall, the research results highlight a very good agreement and a high level of matching between measured values and simulated results, which is a confirmation of the applied energy simulation tool. [ABSTRACT FROM AUTHOR]

Abstract: The paper presents problems related to the assessment of historical objects, especially brick arch structures, in view of potential improvement of their strength using various technologies. We have presented the methodology and computer simulations used for assessment of present strain and load bearing capacity of brick arches along with a variety of reinforcement techniques. We also present arch deformation FEM analysis along with results of assessment of actual objects. [Copyright &y& Elsevier]

Abstract: Ground coupled heat pump systems can offer high energy efficiency for heating and cooling of buildings. The coupling of the ground loop with system and building represents a complex system and system performances can vary over long periods, in the range of 10–15 years due to the charge or discharge of the ground loop. In order to correctly concept, size and optimise these systems, numerical simulation is a perfect tool. The assessment of the global performance of such systems through simulation relies on several parameters, from the physical model validity to the operating conditions and control of the system. Typically, a GCHP system is simulated with a 1-h step. Transient phenomena inside the borehole are often neglected since ground models are mainly developed to characterise long term phenomena. However, detailed system simulations considering a realistic control of the system require much smaller time steps. In these cases, the validity of simulation models has to be verified. This paper proposes a hybrid approach combining experiments and simulation to highlight and quantify the impact of borehole short-time response on the system efficiency and system operation. First, a comparison between steady state and transient models as well as measurement is carried out. It reveals significant influence of dynamic effects inside the borehole. The comparison is then extended a parametric study with annual simulations for different European climates. [Copyright &y& Elsevier]

Abstract: The importance of calculating the effect of thermal bridges in building energy demand is growing. This is because new energy saving regulations are being applied in different countries making builders to increase the level of insulation in homes, and therefore raising the percentage of thermal bridges in total heat loss. This paper makes an introduction to the problem that implies correctly calculating the heat transfer through thermal bridges within the programs to calculate the building energy demand considering their inertia. Different existing models are presented making a comparison between them. This study is carried out in dynamic conditions for two different types of thermal bridges: one with similar inertia to the homogenous wall and the other when the thermal bridge has a much lower inertia. [ABSTRACT FROM AUTHOR]