bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ensemble Numerical Simulations of Realistic SEP Events and the Inspiration for Space Weather Awareness
Authors: Du Chenxi , Ao Xianzhi , Luo Bingxian , Wang Jingjing , Chen Chong , Xiong Xin , Wang Xin , Li Gang 
Published: November 2021

Abstract
The solar energetic particle (SEP) event is a kind of hazardous space weather phenomena, so its quantitative forecast is of great importance from the aspect of space environmental situation awareness. We present here a set of SEP forecast tools, which consists of three components : (1) a simple polytropic solar wind model to estimate the background solar wind conditions at the inner boundary of 0.1 AU (about 20 R
⊙); (2) an ice-cream-cone model to estimate the erupted coronal mass ejection (CME) parameters; and (3) the improved Particle Acceleration and Transport in the Heliosphere (iPATH) model to calculate particle fluxes and energy spectra. By utilizing the above models, we have simulated six realistic SEP events from 2010 August 14 to 2014 September 10, and compared the simulated results to the Geostationary Operational Environmental Satellites (GOES) spacecraft observations. The results show that the simulated fluxes of >10 MeV particles agree with the observations while the simulated fluxes of >100 MeV particles are higher than the observed data. One of the possible reasons is that we have adopted a simple method in the model to calculate the injection rate of energetic particles. Furthermore, we have conducted the ensemble numerical simulations over these events and investigated the effects of different background solar wind conditions at the inner boundary on SEP events. The results imply that the initial CME density plays an important role in determining the power spectrum, while the effect of varying background solar wind temperature is not significant. Naturally, we have examined the influence of CME initial density on the numerical prediction results for virtual SEP cases with different CME ejection speeds. The result shows that the effect of initial CME density variation is inversely associated with CME speed.
Data mining in the context of urban metabolism: A case study of Geneva and Lausanne, Switzerland
Authors: Wiedmann N S , Athanassiadis A , Binder C R 
Published: November 2021

Abstract
The highest share of the global population lives in cities. The current configuration of the latter requires considerable amounts of resource flows causing the degradation of local and global ecosystems. To face the complexity of these challenges, scientists use the concept of urban metabolism (UM), i.e. measuring urban input and output flows from a systemic perspective. This accounting method results in a large data collection from multiple sources that are often not harmonised. Metabolism of Cities Data Hub is an online platform which facilitates data collection, processing and visualisation in order to extract urban metabolism insights. This work highlights the challenges faced when mining urban metabolism data in the case of Lausanne and Geneva, as well as provides insights on how data could be best used from users and providers. Slight differences between the two case studies, in terms of data accessibility and availability where experienced but the main challenges revolved around data copyright, format and availability. As a conclusion, the used tool can enable harmonisation and standardisation of UM data. As such it could contribute to the use of data mining to streamline the environmental monitoring of cities as well as facilitate the creation of mitigation strategies.
ProsNet – a Modelica library for prosumer-based heat networks: description and validation
Authors: Elizarov I , Licklederer T 
Published: November 2021

Abstract
Prosumer-based heat networks are a new concept in district heating systems that uses the ability of prosumers to operate as either producers or consumers. This type of networks allows for utilizing distributed heat generation and renewable energy sources. A broad range of individual operating modes, heat generation technologies, and topologies determine complex thermo-hydraulic behavior of such networks. Simulations help gain insights into their properties. In this paper, a Modelica library ProsNet is presented for such simulations. It is designed to set up models of prosumer-based heat networks to investigate their dynamic and steady-state performance in a user-friendly way. Important models of the library are described in more detail. Finally, a successful validation of the developed components was performed by comparing simulation results with another software for modeling bidirectional heat networks in steady-state.
An assessment of operational economic benefits of renewable energy communities in Belgium
Authors: Felice Alex , Rakocevic Lucija , Peeters Leen , Messagie Maarten , Coosemans Thierry , Camargo Luis Ramirez 
Published: November 2021

Abstract
Renewable Energy Communities (RECs) are anticipated as key means to restructure the energy system in the European Union. However, there are still many open questions regarding the needed conditions that would allow their extensive roll-out. Here we propose a techno-economic model to assess the conditions needed by RECs to operate in an economic beneficial way in the Belgian context. The results indicate that while user type, user consumption and electricity tariff design are important, they are not as important as the amount of installed flexible technology, e.g. heat pumps or electric vehicles, to reduce operational costs. In scenarios with high penetration of flexible technologies the annual operational costs of the REC can be up to 17 % lower than the operational costs of the business-as-usual situation.
The Solar Block Generator: an additive parametric method for solar driven urban block design
Authors: Natanian Jonathan , Luca Francesco De , Wortmann Thomas , Capeluto Guedi 
Published: November 2021

Abstract
This paper addresses the limitations of existing Solar Envelope (SE) methods to explore the trade-offs of solar radiation and urban shading, and to simultaneously account for several different Key Performance Indicators (KPIs). It offers an alternative parametric workflow - the Solar Block Generator (SBG) - which is based on an additive voxelization method by which multiple solar-driven massing alternatives are generated and evaluated for a given site, corresponding to a set of user-defined environmental KPIs. This method is tested here on an urban redevelopment case study in the Mediterranean (Tel Aviv). The results help achieve a more holistic approach for solar driven urban design.
Impact of multiple reflections on urban acoustics
Authors: Bort Inès de , Beckers Benoit 
Published: November 2021

Abstract
Understanding how the urban form contributes to noise is important for the successful acoustic design of cities. The amplification of sound is mainly due to the multiple reflections that occur between the high and parallel walls of urban canyons. This study explores the use of ray tracing at the urban scale through the measurement and simulation of three configurations. These are referred to as “1D”, “2D” and “3D”. Impulse response measurements performed at points located on the top of the façades show an increase of 6 dB for the “2D” case and 11 dB for the “3D” case. These results are consistent with ray tracing simulations. This kind of simulation is useful to determine the influence of the street aspect ratio on the sound level. Since specular reflections are related to geometry, a spatialized representation is proposed and discussed.
A simplified procedure to improve the usability of hydrodynamic modelling software in regenerative urban design
Authors: Pereira Guimarães M. , Moredia Valek A. , Dessi V. , Clementi M. 
Published: November 2021

Abstract
Densely urbanized areas are greatly exposed to the risks from climate change as reported by IPCC in 2018. In particular, compact urban settings afflicted by heavy storms and droughts, coupled with the intensification of the Urban Heat Island (UHI) effect and incremental heat waves require a requalification of the outdoor environment that accommodates for both strategic water management and enhanced microclimatic conditions. The present study proposes simplified procedures to enable the application of complex hydrodynamic modelling software (SWMM), by non-expert users (such as planners and designers), in the preliminary phases of an urban space project according to a water-sensitive urban design approach. In the paper, Italian multi-level regulations aimed at controlling the impacts of excessive rainfall in urban areas are taken into account as well as the integration of circular water management systems with evaporative cooling strategies. The proposed procedure is focused on two aspects: 1- to simplify the steps needed to convert the existing climatic data to provide a numerical sequence, to insert into the software; 2- to define a set of pre-compiled and multi-purposed solutions toolkits for the design of urban spaces that can be imported into the software through an external database.
Optimizing solar access and density in Tel Aviv: Benchmarking multi-objective optimization algorithms
Authors: Wortmann Thomas , Natanian Jonathan 
Published: November 2021

Abstract
This paper explores the trade-off between redeveloping an urban site with higher density and maintaining solar access for the surrounding context in the hot and dry climate of Tel Aviv. Such trade-offs are important for future urban development in the Middle East, where densification is a demographic and environmental need. We explore this trade-off with multi-objective optimization (MOO). Specifically, we benchmark seven MOO algorithms on two test problems with different, parametric typologies: courtyard and high-rise. For both problems, we aim to maximize Floor Area Ratio and the simulation-based Context Exposure Index, a novel metric based on the Israeli green building code. The high-rise emerges as the better performing typology, and HypE, SPEA2, and RBFMOpt as the most efficient and robust MOO algorithms.
Heat flow metering in building practice - A critical field study for a large industrial building complex
Authors: Walther Karl , Voss Karsten 
Published: November 2021

Abstract
Increasingly complex concepts for the heating and cooling supply of buildings require both intelligent and transparent operational management strategies. One way of sequencing and coordinating different generator components is to include information about heat flows on the consumption side. In addition to heat meters, modern pumps also provide heat flow detection. The present study compares the heat flow detection via heat meters and pumps for multiple hydraulic circuits in the operating phase of a large industrial demonstration object. In particular, the influence of typical errors in the installation of the temperature measurement and their elimination are quantified.
District heating network modelling for future integration of solar thermal energy
Authors: Dromart Clement , Puthod Loïc , Kämpf Jérôme H. , Gunten Diane von 
Published: November 2021

Abstract
A key advantage of district heating networks is their ability to integrate different renewable energy sources, from geothermal to solar. However, the success of this integration depends on a variety of design and technical decisions, such as feed-in locations or operating temperatures, which need to be compared and analysed. For this purpose, dynamic models of district heating grids, which allow for an hourly representation of the thermodynamic conditions, are necessary. This type of models are nevertheless still uncommon, drastically limiting options to perform these comparisons accurately. To address this challenge, an open-source tool to model district heating networks is presented here and successfully applied to two case studies in western Switzerland. These simulations are then used in conjunction with simplified models of storage and solar thermal collectors to investigate, in a preliminary way, the impact of solar thermal integration on the mass flow and temperature of the network pipes, illustrating the interest of the proposed method to compare different configurations of renewable heat injections in district heating networks.
Impact of roof geometry on cross-ventilation in vaulted buildings: a CFD study
Authors: Sadeghfar Milad , Sahebzadeh Sadra 
Published: November 2021

Abstract
The roof geometry is an important parameter in determining the natural cross-ventilation in buildings. Although many studies have been performed on natural ventilation, the impact of the large set of vaulted roofs on the building cross-ventilation remains to be addressed. In this paper, high-fidelity computational fluid dynamics (CFD) simulations, validated with experimental data, are performed on five naturally ventilated buildings with two opposing windows, each with a specific type of vaulted roof and otherwise identical, in 0° incident flow angle, to assess the impact of vaulted roof geometry on the building cross-ventilation performance. The following vault geometries are investigated and compared against a flat-roof building with the same specifications: (i) segmental, (ii) low-rise pointed, (iii) mid-rise catenary (iv) high-rise pointed and (v) high-rise catenary. The results show that compared to the flat-roof building, the vaulted roofs cause a <5% decrease in volume flow rate and 16-29% increase in the average mean velocity magnitude at the occupants’ level. In vaulted buildings, the low-velocity regions of the flow are moved further away from the occupied zone towards the ceiling, thus providing a fresher air to the occupants. The results clarify the high potential of vaulted roofs for natural ventilation and sustainable design.
Exploring the relationship between light and subjective alertness using personal lighting conditions
Authors: van Duijnhoven J. , Aarts M.P.J. , van den Heuvel E.R. , Kort H.S.M. 
Published: November 2021

Abstract
The discovery of the ipRGCs was thought to fully explain the mechanism behind the relationship between light and effects beyond vision such as alertness. However, this relationship turned out to be more complicated. The current paper describes, by using personal lighting conditions in a field study, further exploration of the relationship between light and subjective alertness during daytime. Findings show that this relationship is highly dependent on the individual. Although nearly all dose-response curves between personal lighting conditions and subjective alertness determined in this study turned out to be not significant, the results may be of high importance in the exploration of the exact relationship.
Performance gap analysis of a new Minergie A/P district
Authors: Brischoux Pauline , Schneider Stefan , Hollmuller Pierre 
Published: November 2021

Abstract
The eco-district “Les Vergers”, located in Meyrin (Geneva, Switzerland), hosts around 1’350 dwellings and some activities. It is heated by a 5 MWth geothermal centralized heat pump. This study proposes a detailed analysis of the thermal demand of 23 selected buildings in this district as a representative panel of buildings meeting high swiss energy performance standards (Minergie A/P) and equipped with different heat recovery systems. Although the buildings have better thermal performance than the average buildings of Geneva, most show an important performance gap between the actual space heating demand and the design values. A strong correlation between performance gap and cut-off temperature of the heating system suggests that the regulation of the heat distribution system plays a determinant role in the overall performance. Regarding the domestic hot water preparation, the buildings of this district present an average demand 23% lower than the standard value and 31% lower than a benchmark.
Domestic hot water optimizing potential in existing or renovated multifamily residential buildings
Authors: Flourentzou Flourentzos , Pereira Joshua 
Published: November 2021

Abstract
In a Swiss case study of the ReCO2st research project, hot water optimization demonstrated a high potential for energy savings with low investment costs. The optimization started with the end user to reduce first hot water consumption. Energy-efficient showerheads and faucets reduced hot water consumption by 10 to 25%, notably from 65.2 [l/p.day] to 48 [l/p.day] for the period of September to October 2019. A multi-criteria selection of showerheads involved end users considering other qualitative aspects like rinsing efficiency, overall feel of use, noise, and material robustness. Strict control of pipe and storing tank insulation reduced storage and distribution losses. Day and night storage temperature setpoints, water recirculation time, switching off this process after 11:00 p.m., temperature differential of start and stop loading setpoints, creating long loading cycles, ensure that the pipes are not always hot. Reducing Legionella cycles at 60° to once a day avoided the need for continuous high temperatures. The combination of all these soft measures in the Swiss case study resulted in a reduction of energy consumption for hot water of 20-30%. This is equivalent to the installation of expensive solar panels for hot water. A detailed two-year monitoring of the building's hot water consumption shows the contribution of each optimization measure. The encouraging results show that without perfect control of the entire process, it is impossible to avoid a performance gap between planned and actual energy consumption.
Thermal energy autonomy study for a reference house equipped with PV panels, a heat pump and PCM storage elements
Authors: Robadey J. , Vuilleumier S. , Niederhäuser E.-L. 
Published: November 2021

Abstract
Despite their rapid growth, renewable energies cannot provide energy on demand, which is an essential requirement for heating buildings. To this end, we developed heat exchangers with Phase Change Materials that allow the on-demand charge, storage and discharge of thermal energy. In this paper we evaluate the storage capacities needed to achieve thermal energy autonomy. An existing reference house, meteorological data from MeteoSwiss and solar radiation intensity were used to evaluate the thermal needs and the solar power production for the year 2019. To heat the building an air-water heat pump is preferably powered by solar energy. The calculations have been performed from October to March. Using 1200 litres of PCM, a thermal autonomy of 100% was achieved for March and October. In February, November and December, 24 days could not reach a thermal autonomy. For the month of January that was studied in detail 15 days are self-sufficient. By increasing the PCM volume to 2’600 litres 5 more days become self-sufficient. To achieve total building heating autonomy, seasonal storage is necessary.
Comparative Life Cycle Assessment on City Quarter Level – A Case Study of Redensification
Authors: Meier-Dotzler Christina , Harter Hannes , Banihashemi Farzan , Lang Werner 
Published: November 2021

Abstract
The German and European climate action programs and the ongoing discussion of resource efficiency require an in-depth analysis of the building sector, especially with the background of the German refurbishment backlog and high energy demands of the German building stock. A Life Cycle Assessment (LCA) on the city quarter level allows fast and efficient evaluation of environmental impacts, emissions, and energy demands of densification in urban areas. This study presents LCA results for a specific urban city quarter. Thereby environmental and energetic values for specific building ages are developed and used to conduct LCA for the building construction and technical building services components. A 3D city model in CityGML-format of residential buildings serves as the basis for assessment. The results can be used to identify decisive drivers of energy demands and emissions and the saving potentials of different building development scenarios.
Completely geometric theory II: basics of quantum mechanics
Authors: Siparov S V 
Published: November 2021

Abstract
The geometrical approach suggested earlier, makes it possible to investigate the regions both in mega-and micro worlds that cannot be accessed by the direct observation. This makes it possible not only to interpret the basic experiments of quantum mechanics in a new way but also to escape the paradoxes stemming from the wave function introduction. It also gives perspectives to adjust the quantum mechanics and the relativity theory.
Spatio-temporal variation in dry season determines the Amazonian fire calendar
Authors: Carvalho Nathália S , Anderson Liana O , Nunes Cássio A , Pessôa Ana C M , Silva Junior Celso H L , Reis João B C , Shimabukuro Yosio E , Berenguer Erika , Barlow Jos , Aragão Luiz E O C 
Published: November 2021

Abstract
Fire is one of the main anthropogenic drivers that threatens the Amazon. Despite the clear link between rainfall and fire, the spatial and temporal relationship between these variables is still poorly understood in the Amazon. Here, we stratified the Amazon basin according to the dry season onset/end and investigated its relationship with the spatio-temporal variation of fire. We used monthly time series of active fires from 2003 to 2019 to characterize the fire dynamics throughout the year and to identify the fire peak months. More than 50% (32 246) of the annual mean active fires occurred in the peak month. In 52% of the cells, the peaks occurred between August–September and in 48% between October–March, showing well-defined seasonal patterns related to spatio-temporal variation of the dry season. Fire peaks occurred in the last two months of the dry season in 67% of the cells and in 20% in the first month of the rainy season. The shorter the dry season, the more concentrated was the occurrence of active fires in the peak month, with a predominance above 70% in cells with a dry season between one and three months. We defined a Critical Fire Period by identifying the consecutive months that concentrated at least 80% of active fires in the year. This period included two to three months between January and March in the northwest, and in the far north it lasted up to seven months, ending in March–April. In the south, it varied between two and three months, starting in August. In the northeast, it was three to four months, between August and December. By quantifying the role of the dry season in driving fire seasonality across the Amazon basin, we provide recommendations to monitor fire dynamics that can support decision makers in management policies and measures to avoid environmentally or socially harmful fires.