bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessing the effect of the urban morphology on the ambient air temperature of urban street canyons under different meteorological conditions. Application in residential areas of Thessaloniki, Greece
Authors: Tsoka S , Tsikaloudaki K , Theodosiou T , Bikas D
Published: January 2020

This study evaluates the effect of the morphological characteristics of 4 urban districts in Thessaloniki, Greece on the vertical profile of the Tair inside the various urban canyons under different meteorological conditions. ENVI-met v.4 microclimate simulations are conducted for the 4 selected case study areas, while different meteorological boundary conditions are also considered. The obtained simulation results generally suggest significant differentiations on the local climatic conditions throughout the year, due to the diverse morphological characteristics. The analysis of the vertical Tair profile, revealed low deviations during night-time and peak deviations at noon. The maximum Tair discrepancies among all areas have been mainly attributed to the different amounts of solar radiation, received by the canyons’ surfaces and the respective sensible heat release. However, in all cases, the estimated Tair differences among the study areas decreased as the distance from the ground increased.
On the LID systems effectiveness for urban stormwater management: case study in Southern Italy
Authors: Palermo S A , Talarico V C , Turco M
Published: January 2020

Here we present the hydrological effectiveness of Low Impact development (LID) solutions at urban catchment scale, by modelling a highly urbanised area located in South Italy. For the model creation and simulation, PCSWMM based on the Storm Water Management Model (SWMM) was used. The analysis was carried out by considering different land use conversion scenarios including the implementation of LID practices. Therefore, a specific permeable pavement and green roof developed and implemented at full scale at University of Calabria were chosen as source-control measures. The simulations were run by using as input a synthetic hyetograph of 30 min with return period of 10 years. Three hydrological performance indexes, Runoff Coefficient (RC), Runoff Reduction (RR) and Peak Flow Reduction (PFR) were evaluated at subcatchment scale and, a mean value was estimated for an overall evaluation. Main findings show that RR and PFR linearly increase with the reduction of imperviousness due to the modelling of a major percentage of LID solutions, while the RC decreases. In addition, first detailed results reveal the suitability of LID solutions to reduce surface runoff also for the scenario 1 which considers the conversion of only 30% of specific impervious surface in green roofs and permeable pavements.
The potential for rooftop agriculture in the city of Rio de Janeiro: Growing capacity, Food security and Green infrastructure
Authors: Dang M , Sampaio M
Published: January 2020

The research explores the multifaceted benefits associated with the implementation of urban agriculture on roofs in Rio de Janeiro. The city has challenges in terms of food security, urban sprawl and the fragmentation of the green infrastructure. The study aims to look at rooftop agriculture as a multifunctional solution for addressing these concerns. The methodology consisted of: 1) LIDAR-based mapping and detection of all the roofs with an inclination inferior to 5 degrees on 69% of the surface of Rio de Janeiro City, 2) Analysis of the city structure and the key areas presenting a high flat roof potential, 3) Evaluation of the growing capacity of the flat roofs landscape and the yearly demand of vegetables in Rio de Janeiro City, 4) Visualization of the key locations for rooftop agriculture in the region of Bangu using parametric modelling. The research shows that 1,385 hectares of roofs would be suitable for rooftop agriculture within the study region. This productive roof surface could produce enough food to meet the yearly demand for vegetables of 39.2% of the inhabitants of the city of Rio de Janeiro. The study also demonstrates the great relevance of implementing rooftop agriculture in the poorest communities of Rio de Janeiro in the perspective of tackling food insecurity.
Heat transfer between heated, partially heated and non-heated residential units in buildings
Authors: Shesho Igor K. , Tashevski Done J. , Filkoski Risto V.
Published: January 2020

Space heating cost allocation according to actual consumption can be one possible motivating factor for saving energy in residential and other buildings. As a consequence of the exclusion of a certain number of users in collective housing units from the central heating supply system in the city of Skopje, the problem of heating cost allocation and collection of the fixed part of the heat energy payment has arosen. The subject of the analysis in this study was the heat transfer in buildings, with the main focus on the issue of heat transfer rate between residential units with different internal temperatures, such as from heated to unheated or partly heated apartments in collective building objects. The purpose of the analysis was to assess the mutual energy interaction between the completely or partially excluded apartments from the central heating system and the adjacent apartments connected to the central heating system. This is done by simulating the thermal characteristics of typical buildings that are representatives of new (insulated) and old (un-insulated) buildings. For the simulation purposes, the external average daily and monthly temperatures were obtained based on the perennial outdoor temperatures measured in Skopje and additional series of input data that are characteristic for the city were used. For the value of the internal temperature in the dwellings the value for the standard internal design temperatures are predefined. As results of the simulation, values were obtained for the annual heat gains (in kWh/year) and the specific heat gains (in kWh/m2year) of the excluded apartments from the system of central heating through the enclosures (internal walls, ceiling and floor) of the adjacent apartments that are connected to the system for central heating and vertical hot water pipelines for an isolated and nonisolated buildings. In order to obtain a clearer picture, in the study are considered different configurations and positions of apartments in the building. As an indicator for each considered apartment, the ratio of the received thermal energy of the disconnected apartment to the required energy for its heating is calculated. Based on the obtained results, appropriate conclusions were drawn regarding the reduction of the necessary energy for heating of the excluded apartments, as a consequence of the thermal gains through the walls of the neighboring apartments that are connected to the heating system.
Energy performance analysis and low carbon retrofit solutions for residential buildings
Authors: Liapopoulou E , Theodosiou T
Published: January 2020

The aim of this paper is to investigate the energy performance of residential buildings, through a case study of a typical domestic house located in Thessaloniki, Northern Greece. The building’s energy performance is simulated and analysed using the DesignBuilder software. The study then performs a parametric analysis, in which deviation in various parameters is compared against the current situation in the thermal, cooling load and total energy requirements. The significance of changing each parameter is evaluated by considering the energy balance. Finally, the study uses the Analytical Hierarchy Procedure (AHP) to choose the best sustainable retrofit option in order to reduce the carbon footprint in a domestic house. The alternatives considered are sealing the building envelope (installing cavity-wall insulation), on-site energy generation (solar PVTs), installation of energy efficient appliances, and home monitoring with smart meters. The procedure suggests a solution that best meets the criteria of cost, greenhouse gases emissions reduction, and ease of installation. The case study suggests that smart meters monitoring is the best option, followed by cavity-wall insulation.
Life-cycle oriented simulation-supported heating demand optimisation of buildings: An Austrian case study
Authors: Eikemeier S , Wimmer R , Mahdavi A
Published: January 2020

This contribution reports on an ongoing research effort within the project Sim4DLG (FFG 853842) to optimise the performance of life cycle oriented buildings in Austria. For a reduction of the heating demand and overheating risk in the cold and warm seasons respectively, a simulation-supported optimisation strategy was pursued. This approach is applied to a range of different building types, varying from stand-alone single family houses to townhouses and apartments in a multi-storey building, which are to be constructed within the project Life Cycle Habitation (LIFE13 ENV/AT/000741). To avoid overheating risk in the buildings and to increase the thermal comfort, the dimensions of external shading devices were investigated, especially in combination with summer-time natural ventilation. Apart from the exploration of the indoor environment of each building type, the heating demands of the buildings were specifically examined. This includes a comparison of the building parameters and simulation procedures as well as an evaluation of the outcomes and deviations of the simulation results in relation to the concurrently calculated mandatory Austrian energy certificate. The simulation results suggest that this strategy has not only the potential to improve indoor conditions, but also to result in better ratings in terms of the Austrian energy certificate.
District Cooling Application on an Existing District Heating Infrastructure: Technologies and Potential
Authors: Tsigkas Ioannis , Panaras Giorgos
Published: January 2020

The proposed work attempts to examine whether district cooling is a sustainable solution for cooling applications in a modern urban area where there is already a district heating system network installed. In order to make a complete and objective assessment about the aforementioned topic, the majority of factors affected by or affecting such a project is taken into consideration, namely energy, environmental, socio-political or financial issues. The analysis uses as reference system that of the district heating of the city of Kozani, Northern Greece, operating since 1993; the system uses heat produced by the nearby coal power plants. In conclusion, district cooling is assessed as a feasible and sustainable choice for Kozani with multiple benefits for the region. For example, the increase of the pipeline network lifespan by minimizing corrosion due to oxidization, the extended utilization of waste heat, the reduction of the load on the electric power network as more and more customers will shift from air-conditioners to District Cooling and the creation of a variety of either short term or long term jobs during the construction phase and during the lifetime of the installation. Moreover, a variety of suggestions is given for prospective researchers on the topic as well as proposals on the development of the project further than the pilot phase.
Evaluation of measurement techniques for modelling buildings in energy simulation and labelling tool
Authors: Gonzalez-Caceres A , Hempel E E
Published: January 2020

The dwellings built between 1945 and 1980 have the largest energy demand in the EU, which by 2009 represented 70% of the final energy use in buildings. A great portion of these dwellings have not been retrofitted and most of them were not built with any energy efficiency measures, since most of the energy regulations were implemented after the oil crisis in the 1970s. The current renovation rate of residential buildings has not reached targeted goals, due to the numerous barriers that arise in the renovation process. The evaluation and labelling of existing residential buildings represent a big challenge, and the lack of geometric information on buildings is one of the main issues hindering an assessment through simulations. Currently, there is no scientific literature that focuses on improving this task. However, the emergence of new technologies from different fields may streamline the geometric data gathering with the modelling task and greatly improve both accuracy and workload. This study focuses on the revision of geometry measurement techniques, based on the application and quantification of the benefits and barriers that these techniques represent for their use in the building simulation and labelling. The techniques tested were Hololens, handheld laser scanner and handheld laser distance measurer. The evaluation considers time, cost and accuracy as well the tasks related to the post process of the data in BIM, which is not mandatory for building simulation, but it provided multiple benefits.
Use of timber for the sustainable city growth and its role in the climate change.
Authors: Hamadyk E , Amado M , de Brito J
Published: January 2020

According to the predictions of United Nations (2017) there are more than 7 billion people on Earth and this number will reach 9.7 billion by 2050. Today, most of the population lives in the urban areas and the rapid growth entails more construction in a housing sector. Since the industrial revolution the world has experienced countless technological attainments and on the other hand risky increase in natural resources use, energy consumption, greenhouse gases emission, ozone depletion, toxification and global temperature rising. The question how the cities can respond to urban growth is related to the sustainable goals of Agenda 2030. This research discusses potential of the usage of timber as construction material and it also brings the answer to this question. The wood is 100% renewable, recyclable and nontoxic material with capacity to absorb CO2 and perform low embodied energy. The increase of timber use in the construction contributes to sustainable development and to the reduction of waste, CO2 emission, as well as energy consumption. The aim of this paper is to discuss the advantages of using timber as a sustainable solution in urban context, in comparison with most commonly used concrete. The findings demonstrate the value of timber as sustainable construction material.
Achieving nearly zero energy buildings in Greece
Authors: Bololia Maria , Androutsopoulos Andreas
Published: January 2020

Energy consumption of buildings in Europe is still high despite their significant savings potential. The European Union has issued a number of directives to reduce energy consumption in buildings in its Member States. Each country has put in place the best minimum requirements to make its buildings more energy efficient. By the beginning of 2021 at the latest; all new and deep renovated buildings must have almost zero energy consumption. The latter is the subject of this paper, which focuses on identifying Greece’s energy requirements for newly built buildings to meet the requirements of a nearly zero energy building (nZEB).

Two categories of building use are considered: a typical single-family house and an office building which apply bioclimatic design principles that all newly built buildings have to take into consideration, while all four climatic zones of Greece were looked into. The work presents the combinations - scenarios of building envelope characteristics, electro-mechanical installations, and RES technologies used in the modeled buildings, first to meet the minimum national requirements and secondly to reach minimum energy consumption. The calculations made use of the national program for the determination of the energy efficiency of the TEE KENAK building. The results show that combinations of a variety of building envelope components, electromechanical systems, and RES technologies meet the country’s energy saving targets under its 2030 national energy efficiency plans.
Nearly Zero Energy Ports: A necessity or a green upgrade?
Authors: Sifakis N , Tsoutsos T
Published: January 2020

Ports are situated in susceptible, to climate change, areas. The continuous technological advances on the global market and the growth of the trade activities are forcing ports to find new ways to be both competitive and harmonize with sustainable development’s “legislation”. Specifically, this actually means to practically evaluate all the possible actions and the mean which can be utilized in order to achieve their optimization and greenification. The main objective of this paper is to investigate, analyse and evaluate, through the proposed methodology, various energy-related data of the port of Rethymno and propose a hypothetic model to achieve the near Zero Energy Port (nZEP) concept and the criteria that have to be fulfilled in order to accomplish such an innovative purpose. The methodology to assess a port into the nZEP’s concept is presented, including various crucial guidelines and criteria to define a port as nZEP. Last but not least, the research outcomes specify that there are some curtain gaps and opportunities. Thus, this paper establishes an educational and innovative handbook about an initial attempt to greenify a Mediterranean port and adapt it to nZEP’s concept, utilizing good and essential practices and interventions/implementations in order to achieve this intention.
Towards Zero Energy Settlements – A brief note on commissioning and POE within the EU ZeroPlus Settlements
Authors: Meir Isaac A. , Isaac Shabtai , Kolokotsa Denia , Gobakis Konstantinos , Pignatta Gloria
Published: January 2020

Ambitious goals for the upgrade of construction aimed at energy conservation may quite often bounce due to different barriers, from design and detailing, through construction, to commissioning and behavioural ones. To overcome these, this paper focuses on the missing link of the construction process – the Informative Commissioning, the pre and post occupancy monitoring, and the POE, all integral parts of the ZeroPlus EU project. Limitations, barriers and other considerations and complexities encountered through the project’s stages will be presented, alongside the formation of the methodology and some preliminary results of the first case studies to be commissioned.
Sustainable structural intervention methodology for vulnerable buildings from a lifecycle perspective
Authors: Keskin F S , Martinez-Vazquez P , Baniotopoulos C
Published: January 2020

The frequency of disasters recorded around the globe, combined with inadequate enforcement of design codes, the natural deterioration of the existing built fabric and poor use of land due to rapid urbanisation make urban infrastructure vulnerable to experience damage. This eventually creates the need for building retrofitting, which triggers further environmental degradation. Furthermore, the lack of a well-defined approach to guarantee sustainable structural recovery derives on structural interventions focusing on strengthening elements to improve their performance only, hence ignoring the plethora of building deficiencies associated to post-disaster retrofit. The aim of this investigation is therefore to embed structural upgrading within the principles of sustainability while developing the metrics to enable structural damage reduction. This will contribute to optimising post-disaster building interventions. The proposed approach is applied to a pilot case to illustrate identified alternatives for improving the performance of otherwise vulnerable infrastructure from a life-cycle perspective.
Comparative study of measurement and verification (M&V) baseline models for quantifying energy savings in building renovations
Authors: Cabrera Adalberto Guerra , Ntimos Dimitris
Published: January 2020

Measurement and verification (M&V) is the process of quantifying energy savings originated by one or several energy conservation measures (ECM) in an existing building. The estimation of the savings consist of comparing actual energy consumption to the adjusted baseline model. This paper focuses on comparing three approaches for creating baseline models: linear, symbolic regression (SR) and extreme gradient boost (XGBoost); and discusses the advantages and drawbacks on each of them from a practitioner’s perspective. In this paper, these approaches are assessed qualitatively and quantitatively. The qualitative assessment compares the type of model output, interpretability and calibration time. Linear model excels in all three criteria whereas the XGBoost is the worst option for model output and interpretability. SR model is the worst performing in terms of calibration time, but intermediate model for output and interpretability. Quantitative assessment is done through the quantification of prediction errors in 367 buildings after being calibrated with hourly data for a 12-month period. The XGBoost model has the highest prediction accuracy in terms of CVRMSE. The linear model performs significantly well in terms of NMBE. SR preforms well in terms of CVRMSE and has the best median NMBE overall remaining as the most accurate interpretable option. The results show different benefits and drawbacks of each approach and the implementation of SR model for this application is the main innovation of this paper.
Co-creating sustainable urban planning and mobility interventions in the city of Trikala
Authors: Angelidou Margarita , Karachaliou Eleni , Matonaki Anastasia , Christina Karaberi
Published: January 2020

In recent years, the European Union has been promoting social innovation and new business models to support the long-term transition towards low-emission, sustainable urban development. To this end, a demand-driven approach is seen as key to enhancing the wealth of sustainable urban planning and mobility solutions, increasing their relevance and responsiveness to real life challenges, saving public Research & Development investment resources and most importantly, nurturing the uptake of those solutions by their end users. In addition, cities are seen as ideal places of experimentation because they accumulate a wealth of activities and stakeholders, as well as the complex networks and transactions among those. This paper presents results from the Horizon2020 Research and Innovation Project “Cities-4-People”, financed under the ‘Smart, green and integrated transport’ part of the Horizon2020 Work Programme of 2016 - 2017, topic “New ways of supporting development and implementation of neighbourhood-level and urban-district-level transport innovations” (MG-4.5-2016). More particularly, in this paper we present the methodology, results and conclusions for the co-creation of sustainable urban planning and mobility solutions in the city of Trikala. This phase of the project took place during the period April 2018 – September 2018 and was administered by the Trikala project team of the Cities-4-People consortium (Q-Plan International and E-Trikala).
Sustainable development practices and its effect on green buildings
Authors: Abdelfattah A F
Published: January 2020

Sustainable development is an important aspect of society which fulfils the present needs without compromising the ability of future generations to meet their own needs. It gives us a new way of thinking through and managing human impact on the world that can generate long lasting positive results for the greater benefit of human societies. The concepts of sustainability and sustainable development are discussed and analyzed from different theoretical perspectives. The alternative paradigms and main objectives which provide supporting sustainable development are explored. They show the complexity of choosing the right actions towards sustainable development. And, the three pillars of sustainable development which are social, economic and environmental should be considered together to achieve the effective planning for sustainable future through a collaboration of experts from different disciplines. International goals of sustainability have led to the development of the green building movement that has had unprecedented success. Sustainable development and green buildings are often used interchangeably. Although, they are related, they are not the same. There are many green building rating systems over the world. United States Green Building Council administered Leadership in Energy and Environment Design (LEED) is the global market leader in the rating systems. LEED is a laudable and has a great effort in moving towards sustainable development by converting the built environment into green. Furthermore, some other rating systems that have been developed to measure the sustainability level of green buildings and provide best practice experience in their highest certification level are illustrated. This paper aims to provide an overview of how green building relates to sustainable development practices which is divided into two sections. The first section defines green building and discusses what makes buildings green. And, the second section discusses the environmental impacts of traditional buildings and explains common green building practices.
Life Cycle Analysis of lattice and tubular wind turbine towers. A comparative study.
Authors: Stavridou N , Koltsakis E , Baniotopoulos C C
Published: January 2020

Wind energy is the most promising sustainable energy source as one can conclude from the recent boost of wind farms installed globally. It is rather important to investigate the total environmental impacts of wind energy, not only taking into account the zero CO2 emissions when producing electricity from wind but also assessing the total environmental burdens and resources requirement associated with the entire lifetime of all the processes related with the energy chain. In order to quantify the environmental impacts of wind energy life cycle analysis (LCA) is performed. Life cycle analysis of tall onshore wind turbine towers is not very thoroughly investigated in literature, which is a first class opportunity to perform high-end research. More specifically in this work, studies examining the life cycle performance of two types of onshore wind turbine towers are investigated; lattice and tubular. The definition of life cycle analysis and the steps applied for its implementation are also discussed. For Wind Energy LCA five phases are usually taken into consideration: manufacturing and construction, onsite erection and assembling, transportation, operation and finally dismantling. At the first steps of the present investigation, a typical system boundary is taken into account and a literature review summary describing the main conclusions from LCA studies on onshore wind turbine towers are presented. From recent LCA results on onshore wind turbines, the manufacturing stage is proved to have the greatest environmental impact, while recycling (that is used as a preferred scenario instead of reuse in the dismantling phase) is proved to act in the most favourable way. In the present study, two wind turbine towers of the same size and same energy production capacity are investigated and compared. Both structural systems, the tubular and the lattice one are proved robust enough and the total material used for their production is calculated in previous work of the research group. The two systems have different production methods, different amounts of material used and different mounting procedures which diversifies their lifecycle performance as a total and their performance in all LCA phases examined separately. Open LCA software was used to assess the lifecycle performance of the two different wind turbine tower types and very important conclusions were derived. After having performed the structural analysis of the two tower types, the LCA analysis completes the series of criteria that have to be taken into account when deciding between the two tower configurations towards more robust, more economical and more sustainable wind energy structures.
The Role of policies, Regulations and Standards: Towards Sustainability in Kenya’s Building Environment.
Authors: Sangori R. , Kitio V. , Thontteh E. , Omonge S.
Published: January 2020

This study seeks to explore the policy and institutional frameworks including regulations and standards in promoting sustainability. The paper reports an on-going study on how policies, regulations and standards promotes adoption of sustainable building materials and technologies in relation to utilization of location specific materials and their effects on carbon sequestration potential of the natural ecosystem. The study set to establish the building materials sustainability selection criteria techniques, and supporting policies and institutional frameworks. There are 14 sustainability selection techniques available for application by built environment practitioners. Over 20 policies exists in Kenya that addresses climate change, built environment and urbanization against which to evaluate uptake and effectiveness of building materials sustainability selection criteria techniques. This study is purposive in nature as such, key informant questionnaire assisted tool was used. Our findings demonstrate that 77.4% sampled built environment practitioners did not appreciate that current policies adequately support adoption of emerging building technologies. There is low uptake coupled with ineffective sustainability selection criteria techniques. The study recommends review of existing legislations to accommodate emerging technologies and selection criteria tools, financing of pilot projects, standardization of building materials sustainability selection criteria techniques, training and sensitization, and inventory of building materials and sources.
Developing a strategy for energy efficiency in the Egyptian building sector
Authors: Caponigro Marco , Manoloudis Athanasios , Papadopoulos Agis M.
Published: January 2020

Global warming is a major threat for each country worldwide, in particular however for the Middle East and North African (MENA) region. Furthermore, inefficiency has been a common feature of the energy use in most of the MENA countries for the last decades; high subsidies on retail energy prices covered this fact for years, however as the oil prices shrank, this was no longer possible due to reduced revenues. The combination of those two reasons led since the early 2010s some MENA countries to develop energy efficiency (EE) policies, whilst others are trying to catch up. Egypt is the most populous country, facing many challenges: a further significant growth of population and an expected high annual economic growth on the one hand, the need for new infrastructure and the scarcity of water on the other. The present paper focuses on the situation of Egyptian building sector with respect to prevailing energy efficiency regulations and their implantation, as well as on the elaboration of proposals for a viable and effective strategy to improve conditions.
Measurement methods of socioeconomic impacts of renewable energy projects
Authors: Karytsas Spyridon , Mendrinos Dimitrios , Karytsas Constantine
Published: January 2020

The development and operation of renewable energy projects can offer a variety of environmental, economic and social impacts for all associated stakeholders, thus assisting the procedure of social acceptance of such projects. In most cases importance is given to the measurement and assessment mainly of the environmental and economic impacts, leaving behind the investigation of social impacts, although they are an aspect that can enhance projects’ acceptance throughout the lifecycle of the project (planning, construction, and operation). The present study reviews the work that has been done so far regarding the methods for measuring the social impacts created by renewable energy projects, with the aim of enhancing the understanding and facilitating further improvements in the specific field. In this context, the study a) examines all relevant terms as defined by previous literature, b) takes under consideration the importance of measuring social impacts, c) assesses the steps and guidelines involved in social impact measurement, d) investigates applied indicators, metrics and methods, and e) reviews the existing studies that focus on the measurement of socioeconomic impacts of renewable energy technologies and projects.
Serious game for modelling neighbourhood energy supply scenarios
Authors: Prilenska Viktorija
Published: January 2020

Scientific evidence suggests that in developing neighbourhoods, which are under-serviced by centralised energy distribution grids, the reasonable solution is a mix of grid and off-grid energy provision, as well as a mix of fossil fuels and renewable energy sources. The assumption shapes a theoretical foundation for a serious game, Energy Game, which emerged as a result of an international interdisciplinary student collaboration. The aim of the Game, on the one hand, is the simulation of user behaviour choosing between various energy options based on their cost efficiency, and on the other hand, the education of design and engineering students, as well as other interested parties, about neighbourhood energy production and delivery. The outcome of the Game represents a distribution of various energy options across the neighbourhood, and may potentially inform planning decisions about neighbourhood energy provision. The results of game sessions with students indicate the viability of the Game for education, energy demand and supply modelling, as well as highlighted the requirements for enhancing the playfulness of the Game and, apart from costs, the need to include the environmental impact of energy provision options into game mechanics.
Bioclimatic analysis of streets and buildings of the Byzantine period
Authors: Bougiatioti Flora , Oikonomou Aineias
Published: January 2020

The paper focusses on the scale of street configurations and individual buildings of the Byzantine period and investigates, with the use of simulation software (Design Builder®) different parameters of their bioclimatic performance. The study is based on hypothetical, “typical” configurations and consists of two distinct parts:

(a) Quantitative (CFD) analysis of the airflow in typical street configurations. These were derived from the available bibliography on the Byzantine Building Codes, which influenced the front, side and rear distances between buildings of different uses, the building heights, the number and dimensions of the windows, the depth and distances of the projections, etc.

(b) Thermal analysis (heating and cooling period simulations) of a typical two-storeyed house. The design (typology and form) of the building was derived from the available bibliography, while the construction characteristics are assumed to be similar to those of the subsequent historical architecture of the areas around the Eastern Mediterranean.
Rammed earth sustainability and durability in seismic areas as a building material
Authors: Preciado Adolfo , Santos Juan Carlos
Published: January 2020

Rammed earth is one of the oldest materials of the world and has been used as a building material for centuries due to its availability, low cost benefits, auto-construction and bioclimatic capabilities to sustain extreme weathers. Rammed earth and adobe housing are constructed in earthquake prone areas around the world due to these benefits. These earthen materials are used to mainly build load carrying walls with light cover of timber. These auto-constructed buildings are extremely vulnerable to earthquake shaking due to its heavy mass, strength degradation through time and lack of structural integrity among elements. This is a natural and sustainable material that deserves to be investigated in order to be used again as a main construction material against masonry and concrete housing. It is needed to understand its behaviour under different loading conditions to identify the components that convert it into a highly vulnerable material. The present investigation focuses on the durability of rammed earth as a construction material of housing located in seismic areas of Mexico. It is presented a survey on one existing rammed earth house constructed almost 15 years ago. It was extracted soil of the surroundings of the construction site to investigate by laboratory tests the compressive strength of the material as constructed in day one and compared against the existing one. It was observed that the water content plays an important role in the compressive strength. The new earth specimens with similar water content as the existing wall samples, presented five times more compressive strength. Finally, advantages and disadvantages are highlighted about the behaviour and durability of this sustainable material.
Influence of perlite and aerogel addition on the performance of cement-based mortars at elevated temperatures
Authors: Stefanidou Maria , Pachta Vasiliki
Published: January 2020

Structures confront severe damages when subjected to fire, related to the characteristics of the fire (i.e. maximum temperature, duration) and the constructional types and materials confronted. During the last decades, the influence of fire and extreme temperatures on building materials has been induced. In this paper, the influence of perlite and aerogel addition on the resistance of cement-based mortars at elevated temperatures is studied. Four compositions of cement-mortars have been manufactured and tested at 200°C, 400°C, 600°C, 800°C and 1000°C. The mortar mixtures was based on cement I42.5 and siliceous sand (0-4mm) in a Binder/Aggregate ratio of 1/2. A proportion of 20% w/w of aggregates was substituted by perlite, while an addition of aerogel at a proportion of 0.5% w/w of binders was performed. After their exposure at the elevated temperatures, the physico-mechanical properties of the specimens were recorded, concerning: volume change, weight loss, porosity, apparent specific gravity, dynamic modulus of elasticity, flexural and compressive strength. Additionally, macroscopic and microstructural observation was conducted. From the comparative evaluation of the results it was concluded that although the perlite and aerogel addition, reduced the initial strength of the mortar compositions, they had a positive effect on their resistance at elevated temperatures, especially regarding their volume stability and mechanical properties above 800°C.
Treasures gutted by fire. Fire safety design awareness as a consequence of historic building accidents and disasters
Authors: Bakas Iasonas , Georgiadis-Filikas Konstantinos , Kontoleon Karolos J.
Published: January 2020

Many of the emblematic buildings of historical importance that have been constructed throughout human history still survive today. However, a significant number has been destroyed by fire. Despite the impact this loss has on cultural heritage, important lessons can also be learnt, enhancing our understanding on how fires develop in historical structures and why they occur in the first place. A review of the existing fire design approaches, in conjunction with the heritage building values and fundamental conservation principles, initiates a dialogue in terms of acceptable interventions and fire protection solutions. The aim of this study is to provide contemporary scientists, conservation professionals and building owners with an insight of how building physics affect the fire performance of historic structures, highlight common risks following a thorough literature review and discuss the role of the fire and conservation engineer.
Building a new sustainable preconstructed building element
Authors: Tsikaloudaki K. , Theodosiou T. , Giarma C. , Kontoleon K. , Aravantinos D. , Tsoka S. , Tsirigoti D. , Karaoulis A. , Chastas P.
Published: January 2020

This paper presents the primary findings of a research project, aiming to introduce an innovative building module with improved thermophysical and mechanical properties that will serve as a bearing element and/or as an internal partition wall in prefabricated residential buildings. This new building module will comply with current requirements as regards its operation and performance. For the purposes of this investigation, the overall performance of the considered building elements is ensured by the proper configuration and assembly of the involved layers and is verified through analytical and experimental analyses, as well as through measurements at accredited laboratories. The objective of this innovative building element is to establish a building envelope with a high structural, hygrothermal, energy, acoustic, fire and environmental performance, while reducing both the time and cost required to complete its construction. Evidently, the accomplishment of this objective suggests various benefits on both the business sector and the research community. Moreover, the utilization of this building module is influential in terms of social impact, as it promotes the construction of buildings with advanced energy and environmental performance that can furthermore mitigate and adapt to the climate change impacts.
Spherical microwell arrays for studying single cells and microtissues in 3D confinement
Authors: Huang Cheng-Kuang , Paylaga Giovanni J , Bupphathong Sasinan , Lin Keng-Hui
Published: January 2020

Microwell arrays have emerged as three-dimensional substrates for cell culture due to their simplicity of fabrication and promise for high-throughput applications such as 3D cell-based assays for drug screening. To date, most microwells have had cylindrical geometries. Motivated by our previous findings that cells display 3D physiological characteristics when grown in the spherical micropores of monodisperse foam scaffolds (Lee et al 2013 Integr. Biol.
5 1447–55 and Lin et al 2011 Soft Matter
7 10010–6), here we engineered novel microwells shaped as spherical caps with obtuse polar angles, yielding narrow apertures. When used as bare substrates, these microwells were suitable for culturing cell spheroids; the narrow apertures sterically hindered unattached cultured cells from rolling out of microwells under agitation. When only the walls of the microwell were conjugated with extracellular matrix proteins, cells remained confined in the microwells. Epithelial cells proliferated and burst out of the aperture, and cell polarity was oriented based on the distribution of extracellular matrix proteins in the microwells. Surprisingly, single fibroblast cells in spherical wells of various diameters (40–100 μm) underwent cell-cycle arrest, while cells in circular cylindrical microwells continued to proliferate. Spatial confinement was not sufficient to cause cell-cycle arrest; however, confinement in a constant negative-curvature microenvironment led to cell-cycle arrest. Overall, these investigations demonstrate that this spherical microwell substrate constitutes a novel basic research tool for elucidating how cells respond to dimensionality and microenvironment with radii of curvature at the cellular length scale.
Effect of (Pr + Ce) addition and T6 heat treatment on microhardness and corrosion of AlSi5Cu1Mg alloy
Authors: Zou Yongcheng , Yan Hong , Hu Zhi , Ran Qianwen
Published: January 2020

The effects of T6 heat treatment and 0.6 wt% (Pr + Ce) addition on microstructure, microhardness, and corrosion of AlSi5Cu1Mg alloy were investigated. Optical microscopy and scanning electron microscopy revealed that the T6 heat treatment and the addition of 0.6 wt% (Pr + Ce) effectively refined the α-Al and eutectic Si phases, which were uniformly distributed with Al2Cu phase in the alloy. Microhardness, weight loss, hydrogen evolution, Tafel polarization, and EIS tests showed that the combination of T6 heat treatment and 0.6 wt% (Pr + Ce) addition resulted in the best corrosion resistance and microhardness of the alloy. The microhardness of the AlSi5Cu1Mg+0.6 wt% (Pr + Ce)/T6 (115 HV) was 27.8% higher than that of the matrix (90 HV). At the same time, the corrosion current density of the alloy also reached the minimum value (38.4 μA cm−2). The T6 heat treatment and the addition of (Pr + Ce) can significantly decrease the average grain size, change the redistribution of the precipitated Al2Cu phase, refine the Si phase, and increase the pitting formation position, thus reducing the sensitivity of exfoliation corrosion.
Application of porous TiAl intermetallic compound in purification of industrial TiCl4 liquid in Ti metallurgy
Authors: Jiang Yao , He Yuehui , Liu Xinli , Gao Haiyan
Published: January 2020

Industrial TiCl4 liquid, which is a key intermediate in Ti metallurgy, is hard to be purified by traditional porous metals or ceramics due to its characteristics of easy hydrolysis, toxicity and corrosivity. In this work, porous TiAl intermetallic filter tubes were fabricated through a reactive synthesis process, and their filtration properties in industrial TiCl4 liquid were investigated. The cyclic corrosion kinetics of porous TiAl in TiCl4 follows a parabolic rate law, in which the corrosion rate constant is 4.8%, 0.06% and 0.04% of that of porous Ti, Ni and 316L stainless steel, respectively. After the cyclic corrosion of 408 h, the maximum aperture reduction rate of porous TiAl is 3.9%, which is far lower than that of porous Ti, Ni and 316L, indicating good pore structure stability. Porous TiAl filter tubes exhibit clean filtration performance in the solid-liquid separation of raw TiCl4 suspension with stable filtrate solid content of 0.1 wt% and high filtration flux of 8.17 m3 · m−2 · h−1 at the maximum aperture of 17.0 μm. The filtration equation and the filter medium resistance of porous TiAl are determined.
Analytic dependence of the Madelung constant on lattice parameters for 2D and 3D metal diiodides (MI2) with CdI2 (2H polytype) layered structure
Authors: Harutyunyan V S
Published: January 2020

In this theoretical study, the Madelung constant (A

M
) both for a 2D layer and parent 3D bulk crystal of metal diiodides MI2 (M = Mg, Ca, Mn, Fe, Cd, Pb) with CdI2(2 H polytype) structure is calculated on the basis of the lattice summation method proposed in author’s earlier work. This method enabled, both for a 2D layer and 3D bulk crystal of these compounds, to obtain an analytic dependence of the Madelung constant, A

M
(a, c, u), on the main crystallographic parameters a, c, and u. The dependence A

M
(a, c, u) reproduces with a high accuracy the value of the constant A

M
not only for metal diiodides MI2 with CdI2(2 H polytype) structure, but also for metal dihalides (MX2) and metal dihydroxides [M(OH)2] with the same structure. With the use of the high-pressure experimental results available in literature particularly for FeI2, it is demonstrated that the above analytic dependence A

M
(a, c, u) is also valid for direct and precise analysis of the pressure-dependent variation of the Madelung constant.
Effects of graphene addition on the microstructure of 7075Al
Authors: Dong YunFan , Ren BingHui , Wang Kang , Wang Jianrong , Leng JinFeng
Published: January 2020

In this paper, the effect of the addition of graphene on the as-cast and homogenized annealing microstructure of 7075 aluminum alloy (AlZnMgCu) was studied. The analytical model devised in this study has demonstrated the significant grain refinement of graphene-7075 aluminium matrix composites (G-7075) due to large surface area of graphene. The results showed that the as-cast microstructure of graphene-7075 aluminum matrix composite was refined significantly, which the average grain size of the composite decreased from 78 μm to 45 μm and lattice distortion is more significant. The effect of the dissolution of the non-equilibrium eutectic structure and the secondary phase distribution of the graphene-7075 aluminum matrix composite is better after annealing at 470 °C for 16 hours.
Semi-Density Matrices and Quantum Statistical Inference
Authors: Abad Ahmad Shafiei Deh , Shahbazi Mohammad
Published: January 2020

In this paper, inspired by the ‘Minimum Description Length Principle’ in classical statistics, we introduce a new method for predicting the outcomes of performing quantum measurements and for estimating the state of quantum systems.