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Against the background of climate protection and the rising costs of a fossil-fuel-based energy supply, the interest in the energy performance and indoor climate of buildings in real operation is rising. This paper, therefore, deals with the indoor climate investigation of two medium-sized office buildings in Germany by taking measurements over a whole year. These relate to one new building and one refurbished building. Sensors of various types were installed and operated in a large number of office rooms, so that in total results are available for over 100 rooms, typically occupied by one or two persons. The analysis focuses on the indoor temperature in summer and the air quality in winter based on the CO2 concentration. The comfort classes according to DIN EN 16798 including the adaptive comfort approach are used as a basis to cluster the results. Both buildings have movable sun protection and openable windows but no facilities for active cooling. They, thus, represent a large number of existing 'low tech' office buildings in Germany and central Europe. The results reflect the respective building concepts but also show a wide range between the rooms due to the user preferences and behaviour. The refurbished building shows better results, especially in terms of air quality but also in terms of summer room temperatures. This underlines the benefit of the targeted measures as a result of an analysis of the deficits in the existing building before the refurbishment. The additional measures for decentralised mechanical ventilation and passive cooling are having positive effects. As part of the projects, further measures to improve the indoor climate were investigated in both buildings. In one case, this involved CO2 traffic lights to stimulate personal window ventilation in winter, and in the other, the use of newly developed individual ceiling fans supports convective heat dissipation on the human body during hot spells in summer. The positive effect could be demonstrated for both measures. [ABSTRACT FROM AUTHOR]

Decentral monitoring as a contribution towards improving indoor comfort and operation of commercial buildings Many existing non‐residential buildings offer potential for improving the indoor climate and energy performance through improved use and operational management. To do this, however, the conditions must first be measured and assessed so that recommendations for action can be developed. Existing building automation systems are often not sufficiently qualified for these activities. A corresponding expansion of the hardware and/or software is often economically disproportionate. Against this background, room climate measurements were carried out in exemplary buildings with decentralised data loggers of different designs over at least one year. The three buildings selected for this paper have very different ventilation concepts. The two buildings without air conditioning systems showed the influence of user behaviour on the achieved indoor climate level in different ways. The building with an air‐handling system exemplified the influence of an unfavourable set point on energy consumption. Decentralised measurement technology offers great potential for quality assurance in existing buildings. In new buildings, it is necessary to design building automation systems for quality assurance tasks and not only for function assurance. [ABSTRACT FROM AUTHOR]

From 1698, colonial officers and investors from France forged a conglomerate of companies for transforming Saint-Domingue into a sugar colony, thus augmenting incomes of tax farmers and of the crown. Capital was also captured from enemy colonies and generated through trade with Spanish possessions. The most important capital were slaves, both as laborers and mortgageable property—crucial during the War of Spanish Succession, which brought price volatility and speculation in land and sugar. In order to secure the colony's development, authorities restricted rights of owners over their slaves, preventing their sale or abuse. Only around 1715 was such protection of slaves suppressed. [ABSTRACT FROM AUTHOR]

Diese Artikelserie stellt den Einsatz von Computerprogrammen in der Hochschullehre der Bauphysik und Gebäudetechnik für Architekten und Bauingenieure vor. In diesem Beitrag werden die Motivation zur Artikelserie und die Ergebnisse einer Online‐Umfrage an die Lehrenden der deutschsprachigen Hochschulen, initiiert und durchgeführt vom Fachgebiet Bauphysik und Technische Gebäudeausrüstung der Universität Wuppertal, aufgeführt. [ABSTRACT FROM AUTHOR]

The Solar Decathlon is a competition for universities from all over the world which focuses on designing, building and operating experimental, solar-powered houses. Participating in the project offers universities a unique and interdisciplinary platform for teaching, learning and research which combines practical experience with research. In 2022, the European edition was held in Germany for the first time. The event took place with a new urban profile to increase both the relevance of the competition and the learning experience. Its main topic was the further development of the European city, and specifically focused on the existing stock of residential apartment buildings. A total of 18 teams from 11 countries with over 500 students took part, with 16 teams ultimately building their houses on a shared solar campus. Demonstrating a balanced or a positive energy balance in practice was one of the essential goals of the competition. This was achieved by 13 of 15 projects in the energy contest. The prerequisites for this were a high level of energy efficiency and the consistent use of solar energy. Both strategies were embedded in convincing architectural concepts. These ranged from the minimised visibility of standard systems on rooftops, through to custom-built systems with full architectural integration in façades. Hybrid solar systems also became a focus, with the goal of making optimum use of the surfaces on the building envelope. This paper focuses on the energy engineering and technical and architectural integration of the solar systems. It also includes the results achieved in the competition linked to the learning experience. [ABSTRACT FROM AUTHOR]

In this study we present the development of an injectable polymeric drug delivery system for subconjunctival treatment of primary open angle glaucoma. The system consists of hyaluronic acid sodium salt (HA), which is commonly used in ophthalmology in anterior segment surgery, and an isocyanate-functionalized 1,2-ethylene glycol bis(dilactic acid) (ELA-NCO). The polymer mixtures with different ratios of HA to ELA-NCO (1/1, 1/4, and 1/10 (v/v)) were investigated for biocompatibility, degradation behavior and applicability as a sustained release system. For the latter, the lipophilic latanoprost ester pro-drug (LA) was incorporated into the HA/ELA-NCO system. In vitro , a sustained LA release over a period of about 60 days was achieved. In cell culture experiments, the HA/ELA-NCO (1/1, (v/v)) system was proven to be biocompatible for human and rabbit Tenon's fibroblasts. Examination of in vitro degradation behavior revealed a total mass loss of more than 60% during the observation period of 26 weeks. In vivo , LA was continuously released for 152 days into rabbit aqueous humor and serum. Histological investigations revealed a marked leuko-lymphocytic infiltration soon after subconjunctival injection. Thereafter, the initial tissue reaction declined concomitantly with a continuous degradation of the polymer, which was completed after 10 months. Our study demonstrates the suitability of the polymer resulting from the reaction of HA with ELA-NCO as an injectable local drug delivery system for glaucoma therapy, combining biocompatibility and biodegradability with prolonged drug release. [ABSTRACT FROM AUTHOR]

• The Solar Decathlon successfully tackles the triple: design, build, operate. • Competition houses demonstrate net energy positive buildings. • All energy supply systems are based on PV and air heat pumps. • Houses with battery storage provide flexibility in building grid interaction. • Online knowledge platform provides building information and monitoring data. • The competition format can be linked to building science. The Solar Decathlon is a competition for universities from all over the world to design, build and operate small experimental solar powered houses. Its first edition took place in the US in 2002. Since 2010 it is in practice in Europe with four competitions and 65 net zero or net energy plus houses build and tested in 10 disciplines (decathlon). This paper provides an overview and analysis on the European edition of the competition. The work was carried out within the framework of Annex 74 "Competition and Living Lab Platform" of the International Energy Agency and an EC funded project named "Solar Decathlon Europe - Analysis of the Results". The analysis was based on the development of a web based knowledge platform, providing a large set of information and monitored data from past competitions. Based on the availability of information and data, the comparative evaluation is centred on the building energy supply systems and their performance. Starting with very large PV systems, the latest competitions rules trigger the teams to apply systems sized comparable to small buildings in net zero energy building practice. As a result not all houses succeed in a positive energy balance. Due to the wider introduction of batteries the self-consumption of the solar yield and the degree of self-sufficiency increases. New developments of the competition rules stimulate the energy flexibility in operation with the power grid. Modifications for the rules and the monitoring procedure for the next edition intend to further link the competition to building science. [ABSTRACT FROM AUTHOR]

Ceiling fans allow an increase of the local air velocity on the human body. The associated heat transfer increases user's temperature tolerance in warm environments. In the presented study, the differences in the application of statistical turbulence models (RANS) for modelling the air flow induced by a ceiling integrated fan is outlined with particular focus on comparing steady and transient simulations. Results of a CFD simulation (Fluent) are shown and compared with measured data of the horizontal velocity distribution. The study shows that especially the transient simulation using the Realizable k‐ε model shows a stable convergence behaviour regarding the residuals as well as target values. But at 1.1 m above the floor, the mean absolute error of the transient simulation is larger compared to the stationary model using the Multiple Reference Frame (MRF) approach. Despite the stationary model produces an unrealistic velocity distribution in the immediate vicinity of the fan, if the moving zone needs to be small due to obstacles. For a freely suspended ceiling fan, the moving zone can be adjusted accordingly and the flow pattern can be improved. But modelling a ceiling integrated fan with a fan housing and obstacles in the near region, transient simulations using rigid body motion are required for accurate results. [ABSTRACT FROM AUTHOR]

In‐situ measurement of massive building components – Part 1: Comparison of test methods and influences in heating chamber tests In‐situ U‐value measurements are suitable for opaque constructions where a non‐destructive testing of thermal properties is required, e.g. for renovation. In‐situ U‐value measurements are the subject of two research projects from Germany and Switzerland. This Part 1 presents results of the project "LivingLab – Building Performance" at the University of Wuppertal. The aim is to investigate influences on in‐situ U‐value measurement methods for masonry structures in a hot box. It is shown, that in heat flux methods with long measurement periods, size of the heat flux plates and their positioning with respect to mortar joints do not show measurable differences. For uninsulated constructions, this method tends to show lower U‐values, for insulated constructions higher U‐values than calculated. In comparison, short‐term measurements are performed using so‐called "Rapid‐U‐Value Technique (Rapid‐U)". Larger scattering of the results and higher U‐values than with the heat flow method are shown. In Part 2, a research project from Switzerland is presented, in the context of which a practice‐oriented application aid for in‐situ U‐value measurement is being developed. In‐situ U‐value measurements using three different instruments and comparative measurements in the laboratory serve as a basis. [ABSTRACT FROM AUTHOR]

Given the global energy and environmental situation, the European Union has been issuing directives with increasingly demanding requirements in term of the energy efficiency in buildings. The international competition of sustainable houses, Solar Decathlon Europe (SDE), is aligned with these European objectives. SDE houses are low energy solar buildings that must reach the near to zero energy houses’ goal. In the 2012 edition, in order to emphasize its significance, the Energy Efficiency Contest was added. SDE houses’ interior comfort, functioning and energy performance is monitored. The monitoring data can give an idea about the efficiency of the houses. However, a jury comprised by international experts is responsible for carrying out the houses energy efficiency evaluation. Passive strategies and houses services are analyzed. Additionally, the jury's assessment has been compared with the behavior of the houses during the monitoring period. Comparative studies make emphasis on the energy aspects, houses functioning and their interior comfort. Conclusions include thoughts related with the evaluation process, the results of the comparative studies and suggestions for the next competitions. [ABSTRACT FROM AUTHOR]