bluuebunny/crossref_metadata_2025 huggingface dataset:
Individual Differences in Mothers' Spontaneous Infant-Directed Speech Predict Language Attainment in Children With Cochlear Implants
Authors: Dilley Laura , Lehet Matthew , Wieland Elizabeth A. , Arjmandi Meisam K. , Kondaurova Maria , Wang Yuanyuan , Reed Jessa , Svirsky Mario , Houston Derek , Bergeson Tonya
Published: June 2020

Purpose

Differences across language environments of prelingually deaf children who receive cochlear implants (CIs) may affect language acquisition; yet, whether mothers show individual differences in how they modify infant-directed (ID) compared with adult-directed (AD) speech has seldom been studied. This study assessed individual differences in how mothers realized speech modifications in ID register and whether these predicted differences in language outcomes for children with CIs.

Method

Participants were 36 dyads of mothers and their children aged 0;8–2;5 (years;months) at the time of CI implantation. Mothers' spontaneous speech was recorded in a lab setting in ID or AD conditions before ~15 months postimplantation. Mothers' speech samples were characterized for acoustic–phonetic and lexical properties established as canonical indices of ID speech to typically hearing infants, such as vowel space area differences, fundamental frequency variability, and speech rate. Children with CIs completed longitudinal administrations of one or more standardized language assessment instruments at variable intervals from 6 months to 9.5 years postimplantation. Standardized scores on assessments administered longitudinally were used to calculate linear regressions, which gave rise to predicted language scores for children at 2 years postimplantation and language growth over 2-year intervals.

Results

Mothers showed individual differences in how they modified speech in ID versus AD registers. Crucially, these individual differences significantly predicted differences in estimated language outcomes at 2 years postimplantation in children with CIs. Maternal speech variation in lexical quantity and vowel space area differences across ID and AD registers most frequently predicted estimates of language attainment in children with CIs, whereas prosodic differences played a minor role.

Conclusion

Results support that caregiver language behaviors play a substantial role in explaining variability in language attainment in children receiving CIs.

Supplemental Material

https://doi.org/10.23641/asha.12560147
Contributions of Auditory and Somatosensory Feedback to Vocal Motor Control
Authors: Smith Dante J. , Stepp Cara , Guenther Frank H. , Kearney Elaine
Published: June 2020

Purpose

To better define the contributions of somatosensory and auditory feedback in vocal motor control, a laryngeal perturbation experiment was conducted with and without masking of auditory feedback.

Method

Eighteen native speakers of English produced a sustained vowel while their larynx was physically and externally displaced on a subset of trials. For the condition with auditory masking, speech-shaped noise was played via earphones at 90 dB SPL. Responses to the laryngeal perturbation were compared to responses by the same participants to an auditory perturbation experiment that involved a 100-cent downward shift in fundamental frequency (
f
o
). Responses were also examined in relation to a measure of auditory acuity.

Results

Compensatory responses to the laryngeal perturbation were observed with and without auditory masking. The level of compensation was greatest in the laryngeal perturbation condition without auditory masking, followed by the condition with auditory masking; the level of compensation was smallest in the auditory perturbation experiment. No relationship was found between the degree of compensation to auditory versus laryngeal perturbations, and the variation in responses in both perturbation experiments was not related to auditory acuity.

Conclusions

The findings indicate that somatosensory and auditory feedback control mechanisms work together to compensate for laryngeal perturbations, resulting in the greatest degree of compensation when both sources of feedback are available. In contrast, these two control mechanisms work in competition in response to auditory perturbations, resulting in an overall smaller degree of compensation.

Supplemental Material

https://doi.org/10.23641/asha.12559628
Suprathreshold Differences in Competing Speech Perception in Older Listeners With Normal and Impaired Hearing
Authors: Venezia Jonathan H. , Leek Marjorie R. , Lindeman Michael P.
Published: June 2020

Purpose

Age-related declines in auditory temporal processing and cognition make older listeners vulnerable to interference from competing speech. This vulnerability may be increased in older listeners with sensorineural hearing loss due to additional effects of spectral distortion and accelerated cognitive decline. The goal of this study was to uncover differences between older hearing-impaired (OHI) listeners and older normal-hearing (ONH) listeners in the perceptual encoding of competing speech signals.

Method

Age-matched groups of 10 OHI and 10 ONH listeners performed the coordinate response measure task with a synthetic female target talker and a male competing talker at a target-to-masker ratio of +3 dB. Individualized gain was provided to OHI listeners. Each listener completed 50 baseline and 800 “bubbles” trials in which randomly selected segments of the speech modulation power spectrum (MPS) were retained on each trial while the remainder was filtered out. Average performance was fixed at 50% correct by adapting the number of segments retained. Multinomial regression was used to estimate weights showing the regions of the MPS associated with performance (a “classification image” or CImg).

Results

The CImg weights were significantly different between the groups in two MPS regions: a region encoding the shared phonetic content of the two talkers and a region encoding the competing (male) talker's voice. The OHI listeners demonstrated poorer encoding of the phonetic content and increased vulnerability to interference from the competing talker. Individual differences in CImg weights explained over 75% of the variance in baseline performance in the OHI listeners, whereas differences in high-frequency pure-tone thresholds explained only 10%.

Conclusion

Suprathreshold deficits in the encoding of low- to mid-frequency (~5–10 Hz) temporal modulations—which may reflect poorer “dip listening”—and auditory grouping at a perceptual and/or cognitive level are responsible for the relatively poor performance of OHI versus ONH listeners on a different-gender competing speech task.

Supplemental Material

https://doi.org/10.23641/asha.12568472
Ultra‐wideband anomalous reflection realised by a gradient metasurface
Authors: Lin Bao‐qin , Lv Lin‐tao , Guo Jianxin , Wang Zuliang , Huang Shiqi , Huang Baigang
Published: June 2020

In this work, an ultra‐wideband gradient metasurface (GM) is designed by using Pancharatnam–Berry (PB) phase. In the design process, a circular polarisation (CP)‐maintaining metasurface (CMM) is proposed at first, which can realise ultra‐wideband CP‐maintaining reflection in the frequency band of 7.7–19.9 GHz, moreover, PB phase will be generated in its co‐polarised reflection coefficient under CP incidence by rotating the anisotropic resonators in its unit cells. Thus, based on the CMM, an ultra‐wideband GM is designed by using PB phase. Both the simulation and experiment show that the designed GM can realise ultra‐wideband anomalous reflection under arbitrary polarised incidence, the reflected wave under CP incidence will be deflected to an anomalous direction and even be converted to a surface wave; but under linearly polarised and elliptically polarised incidences, the reflected wave will be separated into two beams. In addition, to design more anomalous reflection metasurfaces, the generation principle of PB phase, together with the root cause of the CP‐maintaining reflection of the proposed CMM, has been analysed in detail in the designing process.
Internal wall insulation with a new aerogel panel: SLENTITE®for energetic retrofit in historic buildings
Authors: Günther Eva , Bichlmair Stefan , Latz Sebastian , Fricke Marc
Published: June 2020

We present two recent test case application examples of a new high-performance insulation panel with product name SLENTITE®used as core element of a rendered internal wall insulation system. The first case study refers to the 18th-century building Alte Schäfflerei now the Fraunhofer Centre for Conservation and Energy Performance of Historic Buildings, at the monastery Benediktbeuern, southern Germany, where SLENTITE®was applied in 11/2017. The second test case was installed in 04/2019 in a heritage building situated in the historic center of Luxembourg. In Benediktbeuern, a single layer of insulation material was chosen, in Luxembourg we applied two layers of insulation. In both cases, detail work around the windows was a main task and we gained experience on product processing under real conditions. In terms of indoor room usage, the object in Benediktbeuern is used as exhibition hall with rare traffic and well controlled climate, whereas the object in Luxembourg is used as meeting room without climate control. Measured data of 20 months from the object in Benediktbeuern and first impressions of the performance in Luxembourg are discussed.
The effect of seasonal weather changes on the performance of databased models of the thermodynamic behaviour of buildings
Authors: Hauge Broholt Thea , Rævdal Lund Christensen Louise , Dahl Knudsen Michael , Elbæk Hedegaard Rasmus , Petersen Steffen
Published: June 2020

Several studies have indicated that Model Predictive Control (MPC) of space heating systems can utilize the thermal mass of residential buildings as short-term thermal storage for various demand response purposes. Realization of this potential relies heavily on the accuracy of the model used to represent the thermodynamics of the building. Such models, whether they are grey box or black box, are calibrated using relevant data obtained from initial measurements, and the performance of the calibrated model is validated using data from a subsequent period. However, many studies use validation periods with weather conditions similar to those of the calibration period. Only a few studies investigate whether the calibrated model performs satisfactory when subjected to significantly different conditions. This paper presents data from a simulation-based study on the effect of seasonal weather changes on the performance of a black-box model. The study was conducted using 11 years of Danish weather data (2008-2018). The results indicate that the performance of the black-box model deteriorate as the weather data conditions become increasingly different from those used in the initial model calibration. Further, the results show that calibration in heating season leads to satisfactory model performance through the heating season, but lower performance in transitional seasons (especially spring). Results also show that calibration in February led to highest model performance through heating season, while calibration in March led to satisfactory model performance in the whole heating and fall season.
Impact assessment of climate change on the energy performance of the building stocks in four European cities
Authors: Yang Yuchen , Javanroodi Kavan , Nik Vahid M.
Published: June 2020

Many cities are striving to develop urban transformation strategies, in order to transit from traditional city to a sustainable city. Improving the energy efficiency of the existing buildings is the key to address climate change mitigation and adaptation. This paper considers different climate scenarios using different series of future climate in four different European cities, namely, Kiruna, Stockholm, Valencia and Madrid. The study adopts the TABULA database to get access to basic construction information. Energy simulation and data analysis using IDA ICE and MATLAB are performed. Based on climate change, an overall retrofitting plan was developed by combining energy-saving retrofit solutions. The results show that in Madrid and Valencia, future heating demand will decrease and cooling demand will increase. In Kiruna and Stockholm, with the increase of the insulation material, the heating demand of the house has decreased, but the cooling demand has shown a downward trend compared with the cases of Madrid and Valencia. The first reason is the introduction of hybrid cooling, and the second is that the average indoor temperature has been maintained at 21 degrees Celsius due to the low outdoor temperature in summer. The findings indicate that in Kiruna, Stockholm, and Madrid it is better to insulate façades to lower the heating demand in winter. In Valencia, it is possible to have relatively low heating and cooling demand without façades insulation as insulated façades require more cooling demand during summer.
The use of POD–DEIM model order reduction for the simulation of nonlinear hygrothermal problems
Authors: Hou Tianfeng , Meerbergen Karl , Roels Staf , Janssen Hans
Published: June 2020

In this paper, the discrete empirical interpolation method (DEIM) and the proper orthogonal decomposition (POD) method are combined to construct a reduced order model to lessen the computational expense of hygrothermal simulation. To investigate the performance of the POD-DEIM model, HAMSTAD benchmark 2 is selected as the illustrative case study. To evaluate the accuracy of the POD-DEIM model as a function of the number of construction modes and interpolation points, the results of the POD-DEIM model are compared with a POD and a Finite Volume Method (FVM). Also, as the number of construction modes/interpolation points cannot entirely represent the computational cost of different models, the accuracies of the different models are compared as function of the calculation time, to provide a fair comparison of their computational performances. Further, the use of POD-DEIM to simulate a problem different from the training snapshot simulation is investigated. The outcomes show that with a sufficient number of construction modes and interpolation points the POD-DEIM model can provide an accurate result, and is capable of reducing the computational cost relative to the POD and FVM.
Validation of Hygrothermal Simulations with Wall Performance Experiments in an Environmental Chamber
Authors: Salonvaara Mikael , Boudreaux Philip , Desjarlais Andre , Antretter Florian , Werling Eric
Published: June 2020

Oak Ridge National Laboratory is developing a web tool, built on a rule-based expert system, that aids stakeholders in designing energy-efficient moisture-durable walls. Currently, the tool’s expert system database is mostly populated with expert opinion, but work is being done to incorporate durability assessment based on stochastic hygrothermal modeling. Chamber experiments have been conducted to validate the hygrothermal models. The measured temperature and humidity have been compared with those predicted by the hygrothermal model. Experiments and comparison to one-dimensional hygrothermal modeling results were completed with two walls, a Structural Insulated Panel (SIP) based wall and a Concrete Masonry Unit (CMU) based wall. The two walls were succumbed to typical Chicago weather in ORNL’s Heat, Air and Moisture chamber. The walls were sequentially exposed to different scenarios, including diffusion, wetting, air leakage and solar radiation. For the most part, the hygrothermal simulations can be successfully used to predict the performance of these wall systems for the moisture transport phenomenon. Errors between measured and simulated values decreased as measurements got closer to the interior side of the wall. The root mean square error was larger for relative humidity (up to 17.5%-RH for CMU) than for temperature (up to 4.5°C for CMU wall). The errors were larger for the CMU wall than the wood frame wall. The phenomenon, including liquid water, caused large discrepancies between measurement and simulation results, and simulated results showed slower drying of materials than measured results. The one-dimensional nature of the simulation model made simulating air leaks difficult but not impossible.
Overview of large building testing in Baltic countries
Authors: Nitijevskis Andrejs , Keviss Vladislavs
Published: June 2020

The objectives of this paper are to review measurements of airtightness of 2 large building groups – middle size shops, and warehouses/distribution centres. The mean air leakage rate at 50 Pa pressure difference q50 was 1.04 m3/m2h and 1.35 m3/m2h for shops and warehouses respectively. Analysis of measurement results is valuable because it allows to make a conclusion about compliance of national and corporative construction airtightness norms with actual air barrier condition on a comissioning stage. In the concluding part of the study there are suggested ways to improve air barrier such as review of construction norms, implementation of a mandatory testing and quality control of a measurement.
Occupant comfort in Nearly Zero Energy Buildings (nZEB) by using the building structure for demand side management (DMS)
Authors: Sigg Ferdinand , Krause Harald
Published: June 2020

This research project aims to increase the application range of Thermally Activated Building Systems (TABS). Usually TABS are used for heating and cooling purpose of buildings. The application range of the usage as energy storage element is limited by the surface temperature of the element to avoid overheating. Via a thermal decoupling of the thermal activated part with insulation from the building structure, it is possible to use TABS as an thermal energy storage. The results show a significant opportunity to time-shift the purchase of energy. The results show that it is possible to use TABS as a thermal energy storage element. It’s shown that the purchase of electrician energy for heating purpose can be shifted to economical or ecological optimal time points, for example if renewable energy is abundant in the electrical grid. The heating demand, covered by thermally charged TABS elements can be supplied by a fraction of 95%. Common TABS with a limited surface temperature can reach a coverage rate of 64 %. Nevertheless, the mean air temperature increases for this task by 1.1 K and the heat demand by 15.0 %.
Hygrothermal Behaviour of Ventilation Cavities in Highly Insulated Envelopes
Authors: Viljanen Klaus , Lü Xiaoshu , Puttonen Jari
Published: June 2020

This article presents long-term experimental studies on the moisture safety in the ventilation cavities of highly insulated (HI) structures. The tested HI-walls had thermal transmittances of 0.11-0.13 W/m2K. A wall with a thermal transmittance of 0.23 W/m2K represented the baseline wall in the test. In addition to walls, an HI-roof of a newly built house with a U-value of 0.08 W/m2K was measured. The results indicate that, in the ventilation cavity, the relative humidity of an HI-wall exceeds 1-7% of the humidity measured from the baseline wall during winter, which coincides with the 0.4-1.5ºC lower temperatures observed in the HI-walls. The mold risk in the ventilation cavities of the walls is low, as the value of the mold index (MI) remains below one, which indicates small amounts of microscopic mold only on surfaces. However, at the bottom of the cavity, the MI value reaches 1.4 due to lower temperatures. In the HI-roof, the MI values are between 1.0 and 2.0 in the middle of the cavity in winter. The reasons for the higher mold risk of the roof are the humid weather, the built-in moisture of the roof and the low heat flux from inside. The study confirms that, in the future, warmer weather and increased humidity can increase moisture risks in the ventilation cavities. The results support the use of materials that are more resistant to mold in the outer parts of structures.
Three-dimensional unsteady energy simulation of building envelopes composed of hollow concrete blocks
Authors: Cherem-Pereira Gustavo , Mendes Nathan , Mazuroski Walter
Published: June 2020

Building Energy Simulation (BES) tools commonly use 1-D formulation for computing conductions loads through building envelopes. As this assumption may cause significant errors on the prediction of building energy and thermal performance, this work proposes a methodology for taking into account the 3-D heat transfer phenomenon nature and compare the results for three case studies. The different approach is also used to investigate the effects of considering brick’s cavity detailing with convection and radiation phenomena on the results of transient simulations at the building scale. The present method has the potential to increase precision in the energy analysis of buildings and analyse more precisely the performance of elements of complex geometry. The results demonstrate that traditional simulation methods may not ensure good precision. The magnitude of relative errors varies significantly in each case study.
Analysis of alternative ventilation strategies for existing multi-family buildings using CONTAM simulation software
Authors: Tian Xinxiu , Fine Jamie , Touchie Marianne
Published: June 2020

In many existing high-rise multi-family buildings, a pressurized corridor ventilation system is used to meet outdoor air ventilation requirements. However, this system often has poor performance, leading to under- or over- ventilation in different parts of a building. This study examines three ventilation strategies including: the base case, which is a traditional pressurized corridor ventilation system, a direct-to-suite ducted ventilation system, and a suite-based HRV ventilation system. A building model was constructed in CONTAM using features of a typical post-war multi-family building in Toronto, Canada. All three strategies were simulated using CONTAM under both summer and winter conditions. The resulting outdoor airflow delivery rates to the suites and corridor pressure differentials were compared to assess the effectiveness of each strategy. The results show that the suite-based HRV strategy is able to provide adequate ventilation airflow to individual suites in both summer and winter. In the traditional pressurized corridor system and the direct-to-suite ducting system, the airflows delivered to the suites located at the top of the building are higher than those delivered to the suites located at the bottom of the building. This uneven airflow distribution is more pronounced in winter when stack effect impacts the ventilation system more significantly.
Analysis of Wind Speed and Wind Pressure on the Facades in Frequency Domain for the Modelling of Air Change Rate
Authors: Pietrzyk Krystyna
Published: June 2020

Air exchange in buildings is driven by pressure difference across the building envelope caused by wind and difference in density between external and internal air. The evaluation of the influence of wind on the air change rate is usually limited to the analysis of the hourly mean wind speed. Wind is a random phenomenon characterized by the broad energy spectrum. The high frequency part can be responsible for the oscillation of the air through the openings resulting in the increased air exchange. Wind pressure coefficient on the leeward site mostly depends on the form characteristics of the object in relation to wind direction. The analysis of wind speed and wind pressure on the facades in frequency domain can deliver interesting data to air change rate model. Some of the results of continuous measurements carried out on a single-family house for 8 months are presented in frequency domain. The statistics of wind speed, wind direction and pressure differences across the 6 building components are calculated. The wind turbulence and the pressure fluctuations on the facades and the roof of the building are being investigated using energy spectra of their signals. Farther analysis of the experimental results is needed to be able to include high frequency wind in the infiltration model.
Curtain Wall with Solar Preheating of Ventilation Air. Full Scale Experimental Assessment
Authors: Garay-Martinez Roberto , Arregi Beñat
Published: June 2020

Heating load in Commercial buildings is highly related with ventilation systems, while at the same time local discomfort in the vicinity of glass walls occurs due to overheating. In this paper, a novel double envelope curtain wall is presented, which extracts heat from the façade by means of a ventilated cavity which is then incorporated to the ventilation air intake. A substantial reduction of heating loads is achieved. Whenever solar gains are not sought, a bypass element allows the natural ventilation of this air cavity, acting as a ventilated façade. An integrated control system with embedded electronics and actuators allows for a smart control of the system. The system is designed for integration with existing rooftop ventilation systems. Design considerations are discussed, and the outcomes of a full-scale experiment conducted in Bilbao (Spain) along 2019 presented.
Treatment and analysis of smart energy meter data from a cluster of buildings connected to district heating: A Danish case
Authors: Johra Hicham , Leiria Daniel , Heiselberg Per , Marszal-Pomianowska Anna , Tvedebrink Torben
Published: June 2020

District heating has been found to be a key component of future and reliable smart energy grids comprising 100% of renewable energy sources for countries with dominant heating season. However, these systems face challenges that require a deeper understanding of the coupling between the distribution networks and the connected buildings, to enable demand-side management and balance the intermittence of renewables. In recent years, many smart energy meters have been installed on the heating systems of Danish dwellings connected to district heating, and the first yearly measurement data sets of large building clusters are now available. This article presents the methodology for the pre-processing and cluster analysis (K-means clustering) of a one-year-long smart energy meter measurement data from 1665 Danish dwellings connected to district heating. The aim is to identify typical household daily profiles of heat energy use, return temperature, and temperature difference between the supply and the return fluid. The study is performed with the free software environment “R”, which enables the rapid extraction of information to be shared with professionals of the building and energy sectors. After presenting the preliminary results of the clustering analysis, the article closes with the future work to be conducted on this study case.
Cost reduction of the new NZEB Wooden building – case study of the kindergarten in Estonia
Authors: Arumägi Endrik , Kalamees Targo
Published: June 2020

In this study the cost changes caused by the implementation of the nZEB solutions are calculated. The energy demand of a building was calculated according to the methodology for calculating the energy efficiency of buildings, using dynamic energy simulations. The financial calculations are based on the methodology described in Delegated Regulation (EU) No 244/2012 of the European Commission. The simulations and calculations for assessing the cost-effectiveness of technical solutions are based on the selected sample building. The energy efficiency solutions are derived by increasing/decreasing the insulation value of the building envelope in subsequent steps. Financial calculations were based on the investment needed to achieve the nearly zero-energy levels. The results for different combinations vary to a large degree. According to regulations new building must fulfill the low energy building (EPI class “B”) requirement without local production. The EPI value to fulfill the requirement in the cost-even range is reached in case of the GSHP and efficient DH. In case of the GSHP and efficient DH also the cost-optimal point is in the EPI class “B”. Overall the minimum ΔNPV values stay below the zero line in all the cases offering a range of opportunities to choose combinations to reach lover EPI compared to base case. The results of cost-effectiveness calculations for selected building with different combinations of structural solutions and heat sources show the possible different scenarios to reach nZEB level and the possible cost reduction.
Implementation of a method for converting soil properties into building physical material properties
Authors: John Grunewald , Hauke Hirsch , Hans Petzold
Published: June 2020

This article presents a method that can be used to convert soil properties into building physical material properties that meet the requirements of modern codes for transient hygrothermal simulations. The soil input data must be specified by the so-called “van Genuchten parameters” in order to predict the water retention curve and the hydraulic conductivity of unsaturated soils. The percentages of silt, sand and clay are used to calculate the moisture-dependent thermal conductivity for soils with different water saturation. The output is a validated set of hygrothermal material functions (moisture storage function, liquid water conductivity, water vapour conductivity, thermal conductivity), which is prepared for use in simulation projects or for inclusion in a database. The methodology described in this document has been implemented in an MS Excel tool that enables an efficient, almost fully automatic conversion of a list of soils in three steps.
On the importance of desiccant during the determination of water vapor permeability of permeable insulation material
Authors: Colinart Thibaut , Glouannec Patrick
Published: June 2020

Water vapor permeability of building materials is usually measured using dry cup test according to the ISO 12572 standard. For this test, suitable adsorbing desiccant should be used to provide stable low vapor pressure conditions within the cup and, thus, to ensure the good accuracy of the measurement. In this work, different adsorbing desiccants mentioned in the ISO 12572 standard are tested for measurements performed on wood fiber insulation. For each experiment, relative humidity is monitored inside the dry cup. The results indicate that 0 %RH is not reached inside the dry cup and boundary condition is not always stable for highly permeable construction materials, depending on the adsorbing desiccants. The impact of these observation is evaluated on the determination of water vapor diffusion resistance factor and compared to other sources of uncertainties.
Impact of urban densification on building energy consumption
Authors: Liu Dalong , Wang Wenqin , Ge Hua
Published: June 2020

The close layout of buildings is an important cause of urban densification. It makes solar radiation and long-wave radiation being blocked, scattered, and reflected multiple times. Radiant heat is a key factor affecting building energy consumption. The formation mechanism of urban radiation field in the spaces surrounded by dense buildings was analysed. Calculation models were established for the intensity of short-wave and long-wave radiations in spaces surrounded by dense buildings. Characteristics of the radiation field in the enclosed space was analysed. Two typical cities were selected for the analysis of the impact of urban densification on building energy consumption in the hot summer and warm winter zones of China. Studies have shown that the cooling energy consumption of residential buildings in enclosed space can be reduced by 7-15% compared with open space in China's hot summer and warm winter areas. This research will lay the foundation for urban design and architectural design.
Contrasting Definitions of High Energy Performance Buildings
Authors: Verhaeghe Charlotte , Amaryllis Audenaert , Verbeke Stijn
Published: June 2020

The rising interest in low energy building has led to an inflation in related terminology: (nearly) zero energy buildings, or (n)ZEBs, passive houses, positive energy buildings and districts, off-grid buildings, energy autarkic buildings, etc. Each of these terms involves (sometimes subtle) differences in interpretations, system boundaries, included energy end uses, etc. This paper maps the differences and overlaps in applications of various cases of residential High Energy Performance Buildings (HEPBs), aiming to contribute in the development of a novel taxonomy to evaluate the extent to which a building can be considered energy or carbon neutral. Three dimensions are suggested for specification in novel taxonomy for HEPBs: (i) the spatial dimension (energy use, locally renewable energy production and sometimes energy storage), (ii) the time dimension (during which period is the building and its systems balanced, e.g. yearly or momentary) and (iii) the end-use dimension (these are the end-uses that are included or excluded for the calculation of the total energy needs of the buildings).
Time Domain Reflectometry (TDR) technique – A solution to monitor moisture content in construction materials
Authors: Stingl Freitas Teresa , Sofia Guimarães Ana , Roels Staf , Peixoto de Freitas Vasco , Cataldo Andrea
Published: June 2020

Measuring moisture content in building materials is crucial for the correct diagnosis of buildings’ pathologies and for the efficiency evaluation of the treatment solution applied. There are several different techniques available to measure the moisture content in construction materials. However, perform long-term minor-destructive measurements is still a great challenge. The TDR – Time Domain Reflectometry – technique is commonly used for moisture content measurements in soils, but is considered a relatively new method with regard to its application in construction materials. In the present state of research, the current use of the TDR technique for monitoring moisture content in all types of consolidated porous building materials is not possible yet. Indeed, the empirical conversion functions proposed for soils are mostly not suitable for building materials. Furthermore, to successfully use the TDR technique, a good contact between the TDR probe and the material under study is required, which may be difficult to achieve in hard materials. In this paper, the TDR technique was implemented in two limestone walls constructed in the lab to test experimentally the efficiency of a wall-base ventilation channel to speed up drying after a flood. Each wall was equipped with four two-rod TDR probes for continuous monitoring the moisture content in both situations: with and without the ventilation channel. All the equipment used, procedures followed during the drilling until the probes’ final installation, as well as the individual calibration required for each probe are explained in detail. Instead of using unsuitable functions proposed for soils, the evaluation of the moisture content from the apparent relative dielectric permittivity measured was established using as reference method the gravimetric method. The results obtained suggest that the TDR technique is suitable for moisture content monitoring in consolidated porous building materials.
Experimental investigation of the drying behaviour of the building materials
Authors: Zhao Jianhua , Meissener Frank , Grunewald John , Feng Shuo
Published: June 2020

The drying process gives an important insight for material characterization, during which the material experiences the moisture changing from saturation until the equilibrium with the environment, thus it sends both the liquid and vapor transport information. Drying in the material is a complex process that involves the simultaneous heat and moisture transfer. Due to its complex mechanism, currently there is no stipulation/rules on standardizing the drying test procedure of the moist building materials. In this paper, the drying behaviours of two building materials, ceramic brick and calcium silicate, are experimentally investigated. Different factors that influence their drying behaviours are explored. The approaches to assess the drying rate in two drying phases are also compared and discussed.
Development of prefabricated insulation elements for buildings with aerated autoclaved concrete walls
Authors: Pihelo Peep , Kalamees Targo
Published: June 2020

An extensive need for the refurbishment and renewal of existing building stock has been the focus of consideration for many decades, principally because of the high global energy consumption and pollution levels. This paper presents the results of the analysis of certain sets of timber frame prefabricated insulation elements for the major renovation of an apartment building. The hygrothermal measurements were taken, and a series of combinations with elements were analysed using building performance simulation software to compare the main hygrothermal properties. The critical initial moisture content for the surface section of the aerated autoclaved concrete (AAC) panel is w = 65 kg/m3 at a depth of 15 mm and w = 39 kg/m3 at a depth of 70 mm. The results showed that before the design and installation of insulation elements, thorough hygrothermal analysis of the original external envelope, with actual climatic conditions and moisture loads, must be realized.
The effect of PCM layer on the natural air flow movement in the façade cavity of BiPV system
Authors: Čurpek Jakub , Čekon Miroslav
Published: June 2020

The incorporation of a phase change material (PCM) in building integrated photovoltaic (BiPV) façade can be applied to improve its thermal performance including more effective electrical conversion, however their real interaction needs to be investigated at adequate level. The aim of the presented paper is focused on the application of a material with high latent heat capacity based on PCM in the structure of double-skin BiPV façade. The key aspect concerns on an analysis of natural air flow movement affected by the storing/releasing heat energy from the PCM during daytime/night-time of days. The experimental campaign was performed using an experimental outdoor test cell where two full-scale façade samples (reference BiPV and experimental BiPV/PCM) were investigated. The strong effect of thermal inertia of the PCM identified by experimental measurements was observed on the façade air cavity temperature and air flow movement. Experimental results revealed that natural air flow regimes in façade cavities are nearly equal in the daytime, but in the night-time are totally different. The thermal emission from PCM increase the air temperature in the façade cavity and increase the velocity of air flow movement (PCM started solidified), mainly in the night-time.
Energy saving Architecture: Background, Theory and Practice in Kyrgyzstan
Authors: Boronbaev Erkin
Published: June 2020

This paper for the first time presents a set of background, theory and practice of energy saving architecture of buildings that allows harmonization of appropriate thermal “behaviour” of the building itself with the energy saving behavioural actions of the people in it depending on year-round and daily dynamics of renewable energy of an environment and incoming solar radiation. Energy saving architecture offers a solution to the two-fold task of saving energy and ensuring acceptable internal conditions due to the beneficial influence of natural processes of the building and human behaviour. It is aimed to provide year-round acceptable parameters for the internal microclimate and sanitary-hygiene conditions and to minimize heating, cooling, and ventilation energy consumption. This paper presents the derivation of the formula on the dimensionless indicator of the building’s energy efficient form; its values of the real building forms; examples of solved computational optimization of the location, orientation, and size of the building, and its rooms and thermal envelope components (especially windows and doors). Considerations include issues of minimizing the effect of thermal bridges, especially architectural ones, as well as the structural and operational bridges from the author’s classification. The architectural, constructional, and operational practices are demonstrated by: passive gain and prevention of solar heating; heating and cooling by natural ventilation.
Predicting mould growth on building materials- the PJ-model
Authors: Johansson Pernilla , Svensson Thomas
Published: June 2020

Mould growth in buildings is a complex process, affected by moisture and temperature, the properties of the building material as well as characteristics of the mould fungi. The complexity poses challenges when assessing the risk of mould growth in buildings. Mathematical models are often used to predict whether mould will grow in a part of building with expected RH and temperature conditions. The models can be described as static or dynamic. In a previous round-robin study, comparing results from models with observations from field studies, the outcome of the dynamic models evaluated depended on the user of the model. Also, the models often underestimated the risk of mould growth. A better agreement was found for static models, especially for the PJ-model. It is a part of a standardised technical specification (SIS-TS 41:2014) and has not previously been described as a model. The critical moisture level (RHcrit), determined by tests according to the method, is used as input. Thus, the subjectivity in the predictions is reduced. RHcritis the lowest moisture level at which mould can grow and is temperature-dependent. The PJ-model provides an equation to estimate RHcritat typical temperatures in buildings. If RH in a building section exceeds the limit values at the current temperature, growth is predicted. This paper describes the PJ-model version 1.0, some of the extensive work performed during the development and validation of the model and the ongoing work to refine the model to include considering transient conditions and measurement uncertainties.
Investigation of the Mould Resistance Design (MRD) model for mould growth in attics
Authors: Hansen Thor , Wallentén Petter
Published: June 2020

Based on measurements of mould in 17 attics in the north of Sweden, 3 were chosen as a tentative validation of the MRD-model (Mould Resistance Design) for long periods of time (1961-2012). Comparing the measurements and the results from the simulations showed great differences regarding the mould growth depending on the simplifications used in the model. How the leakage was simulated and where the moisture from the leakage was placed in the construction were the most important factors. The study could not validate the MRD model as such, but it was clear that the simulations with relatively small adjustments could give realistic data
Monitoring and continuous Commissioning of new and existing Buildings
Authors: Olli Teriö , Ilkka Räinä , Markku Hienonen , Hannu Kääriäinen , Timo Kauppinen
Published: June 2020

In the building industry, the quality control practices during the design stage, implementation, introduction and use varies. Also, the owner´s project requirements may vary. The instrumentation, measurements and the control options are different. The final product of the building process is the indoor environment. When evaluating the need of renovation of existing buildings and to control the performance of a new building, certain procedures are needed. Building automation system collects information for control of the building systems and for the users and stakeholders. The validity of the system depends on the level of instrumentation, data processing and reporting. The level of measurements can`t be equal in all buildings. Apartment houses does not need such installations than e.g. hospitals. It is obvious, anyhow, that the data collection, processing and reporting need to be improved. The new sensors and data transfer technologies give a better opportunity to do so. In new buildings it is possible to measure the performance of certain structural details and compare the results with the models. The actual performance does not necessarily fit the planned because there can be always some differences and deficiencies after construction phase. The planning of renovations must be based on condition assessment, and normally there are various measurements carried out and also documents are checked, if there are measurement records available Because the performance and indoor conditions are the sum is the integration and function of all the systems together, measurements can reveal deficiency and inefficiency of building systems.. In this presentation some examples and measures are introduced, based on the city of Oulu, Finland. The advantages of commissioning-type monitoring are discussed. The key point is to have proper measurements and especially proper reporting.
Reliability of the detection of moisture and mould damage in visual inspections
Authors: Annila Petri J. , Lahdensivu Jukka
Published: June 2020

Moisture and mould damage are common in Finnish public buildings. Due to the possible health hazards of such damage, more efficient detection methods and protocols are needed to examine it. The aim of this study is to examine the reliability of visual inspection in the detection of moisture and mould damage. The study points out that the reliability of all the research material is 70%. The highest reliability values concentrate on those structures where the repair need is highest. However, the range of reliability values is wide: from 0% to 100% depending on the age of building or structure. Reliability is highest in the most simplified structures and lowest in structures consisting of multiple layers of different building materials.
Study on the Cooling Effect of Window Gardens
Authors: Ren Jing , Tang Ming fang
Published: June 2020

Window gardens are known to provide a window view with psychological and physiological benefits, whether they can be used for passive cooling of buildings remains to be investigated. This paper aims to supplement the impact of window gardens on the thermal performance of windows, walls, and even indoor air temperatures, which previous research has ignored. A field experiment was conducted for two classrooms with integrated planting troughs outside the windows, with and without living plants. The indoor air temperature and the interior surface temperature of the two classrooms were measured on a typical hot summer day, with windows closed and air conditioners switched off. The results show that: Window garden with living plants can not only reduce the average temperature of the indoor air by 1.1 ℃, but also reduce the average temperature of the interior surface of the building envelope by 2.8 ℃, the reduction of interior surface temperature is more obvious, which is due to the formation of a cold bridge. Therefore, Window garden can improve the summer indoor thermal environment in hot summer and warm winter area in China.
Arabic Science of Light: The birth of modern optics and of the experimental method
Authors: Boudrioua A. , Chergui M. , Rashed R.
Published: June 2020

A millenium ago, the world witnessed a major revolution via the field of Optics. The study of Light, freed from postulates and axiomatic approaches, by the Arab Scholar Ibn-Al-Haytham marked the birth of the experimental method with its observational and analytical protocols, and the use of mathematics in formalising them. This revolution lead to the awakening of Sciences in Europe throughout the middle ages till the Renaissance.