SwePub
Sök i SwePub databas

  Extended search

Träfflista för sökning "WFRF:(Olofsson Thomas 1968 ) "

Search: WFRF:(Olofsson Thomas 1968 )

  • Result 1-50 of 155
Sort/group result
   
EnumerationReferenceCoverFind
1.
  • Dyrek, Achrène, et al. (author)
  • SO2, silicate clouds, but no CH4 detected in a warm Neptune
  • 2024
  • In: Nature. - 0028-0836 .- 1476-4687. ; 625, s. 51-54
  • Journal article (peer-reviewed)abstract
    • WASP-107b is a warm (approximately 740 K) transiting planet with a Neptune-like mass of roughly 30.5 M⊕ and Jupiter-like radius of about 0.94 RJ (refs. 1,2), whose extended atmosphere is eroding3. Previous observations showed evidence for water vapour and a thick, high-altitude condensate layer in the atmosphere of WASP-107b (refs. 4,5). Recently, photochemically produced sulfur dioxide (SO2) was detected in the atmosphere of a hot (about 1,200 K) Saturn-mass planet from transmission spectroscopy near 4.05 μm (refs. 6,7), but for temperatures below about 1,000 K, sulfur is predicted to preferably form sulfur allotropes instead of SO2 (refs. 8,9,10). Here we report the 9σ detection of two fundamental vibration bands of SO2, at 7.35 μm and 8.69 μm, in the transmission spectrum of WASP-107b using the Mid-Infrared Instrument (MIRI) of JWST. This discovery establishes WASP-107b as the second irradiated exoplanet with confirmed photochemistry, extending the temperature range of exoplanets exhibiting detected photochemistry from about 1,200 K down to about 740 K. Furthermore, our spectral analysis reveals the presence of silicate clouds, which are strongly favoured (around 7σ) over simpler cloud set-ups. Furthermore, water is detected (around 12σ) but methane is not. These findings provide evidence of disequilibrium chemistry and indicate a dynamically active atmosphere with a super-solar metallicity.
  •  
2.
  • Brembilla, Christian, 1983- (author)
  • Efficiency factors for space heating system in buildings
  • 2018
  • Doctoral thesis (other academic/artistic)abstract
    • The thesis focuses on the efficiency of the space heating system. In particular, the efficiency factors measure the efficiency of thermal zone. The efficiency factors measures how the energy is used in a space heating. Efficiency factors relatively close to one mean that the energy is used "efficiently'', by contrast, efficiency factors close to the zero mean that the majority of the energy is lost to the outdoor environment. This method for the appraisal of space heating performance reads as if it is apparently simple and intuitive. In reality, the efficiency factor method has several pitfalls.The thesis provides tools, insights and remarks on how to apply the efficiency factor method to space heating systems equipped with hydronic panel radiator and floor heating respectively. Models of the latter heaters together with the multilayer wall were developed and validated to understand the reliability of their predictions. The hypothesis is that the heat stored in the building thermal mass and heaters plays a role in defining the building thermal performance and as a result in the appraisal of the efficiency factors. The validation is based on the sensitivity bands of the models' predictions. The heaters were tested in in a thermostatic booth simulator. Benefits and drawbacks of each model were highlighted to increase awareness of their use in the engineering fields. The results showed how the models accounting for the heat stored performed the charging phase. In addition, results of how the multilayer wall delayed and damped down the heat wave coming from the outdoor environment were presented with the appraisal of the decrement factor and time delay of the indoor temperature. The results of the efficiency factors analysis reveal how the weather affects the efficiency of each locality situated in cold climates. Lastly how different control strategies impact on the efficiency factors of space heating and its distribution system. To conclude, this study highlights the paradoxes around the efficiency factor method. The thesis proposes how such factors have to be interpreted by researchers and scientists tackling the lack of information around this topic.
  •  
3.
  • Brembilla, Christian, 1983-, et al. (author)
  • Hybrid heating system for open-space office/laboratory
  • 2015
  • In: Energy, Science and Technology 2015. - Karlsruher, Germany : Karlsruhe, KIT. ; , s. 315-315
  • Conference paper (peer-reviewed)abstract
    • Open-space office/laboratory are quite common in Scandinavia and they are usually designed for multipurposework. There are office area where is possible to work standing up and in the same time to work at the desk. Forthis purpose a hybrid heating system made by electric convectors and panel radiators is investigated. Two stepresponse tests of the hybrid heating system are performed at the laboratory of Umeå University. The first test isexecuted during the week, disturbances from heat sources degrading the quality of the results. The second test isperformed during week-end. The error analysis shows a maximum discrepancies of +0.6 °C between measuredand simulated data. However, a thermal time constant of the room can be deducted and use it for controlling purposes.
  •  
4.
  • Brembilla, Christian, 1983-, et al. (author)
  • Hybrid heating system for open-space office/laboratory
  • 2015
  • In: Energy, Science and Technology 2015. - Karlsruhe : Karlsruher Institut für Technologie (KIT). ; , s. 315-315
  • Conference paper (peer-reviewed)abstract
    • Open-space office/laboratory are quite common in Scandinavia and they are usually designed for multipurpose work. There are office area where is possible to work standing up and in the same time to work at the desk. For this purpose a hybrid heating system made by electric convectors and panel radiators is investigated. Two step response tests of the hybrid heating system are performed at the laboratory of Umeå University. The first test is executed during the week, disturbances from heat sources degrading the quality of the results. The second test is performed during week-end. The error analysis shows a maximum discrepancies of +0.6 °C between measured and simulated data. However, a thermal time constant of the room can be deducted and use it for controlling purposes.
  •  
5.
  • Brembilla, Christian, 1983-, et al. (author)
  • Investigation of thermal parameters addressed to a building simulation model
  • 2015
  • In: Energy, Science and Technology 2015. - Karlsruher, Germany : Karlsruher Institute of Technology (KIT). ; , s. 128-
  • Conference paper (peer-reviewed)abstract
    • Introduction The uncertainty of setting input parameters in a building model can have a major impact on the simulated output. The tolerance of thermal parameters is a necessary information that helps modeler to know the influence of eachfactors on the outcomes. This paper shows the allowable tolerance of thermal parameters in order to build anaccurate building model.
  •  
6.
  • Brembilla, Christian, 1983-, et al. (author)
  • Investigations of thermal parameters addressed to a building simulation model
  • 2015
  • In: Proceedings of BS2015. - India, Hyderabad : International Building Performance Simulation Association (IBPSA). ; , s. 2741-2748, s. 2741-2748
  • Conference paper (peer-reviewed)abstract
    • This paper shows the tolerance of thermal parameters addressed to a building simulation model in relation to the local control of the HVAC system. This work is suitable for a modeler that has to set up a building simulation model. The modeler has to know which parameter needs to be considered carefully and vice-versa which does not need deep investigations. Local differential sensitivity analysis of thermal parameters generates the uncertainty bands for the indoor air. The latter operation is repeated with P, PI and PID local control of the heating system. In conclusion, the local control of a room has a deterministic impact on the tolerance of thermal parameters.
  •  
7.
  • Brembilla, Christian, 1983-, et al. (author)
  • Paradoxes in understanding the Efficiency Factors of Space Heating
  • 2019
  • In: Energy Efficiency. - Dordrecht : Springer. - 1570-646X .- 1570-6478. ; 12:3, s. 777-786
  • Journal article (peer-reviewed)abstract
    • Efficiency factors are here defined as the thermal energy performance indicators of the space heating. Until recently, the efficiency factors were assumed as one value for space heating located in any climate. This study addresses the problem of how the outdoor climate affects the efficiency factors of a space heating equipped with 1D model of hydronic floor heating. The findings show how the efficiency factors, computed with two numerical methods, are correlated with the solar radiation. This study highlights the paradoxes in understanding the results of efficiency factors analysis. This work suggests how to interpret and use the efficiency factors as a benchmark performance indicator.
  •  
8.
  • Brembilla, Christian, 1983-, et al. (author)
  • The impact of control strategies on space heating system efficiency in low-energy buildings
  • 2019
  • In: Building Services Engineering Research & Technology. - London : Sage Publications. - 0143-6244 .- 1477-0849. ; 40:6, s. 714-731
  • Journal article (peer-reviewed)abstract
    • In this study efficiency factors measures the thermal energy performance for space heating. This study deals with the influence of control strategies on the effriciency factors of space heating and its distribution system. An adaptive control is developed and applied to two types of heating curves (linear and non-linear) for a low-energy building equipped with renewable energy sources. The building is modelled with a hybrid approach (law driven + data driven model). The design of the floor heating is calibrated and validated by assessing the uncertainty bands for low temperatures and mass flow rate. advantages and disavantages of linear and non-linear heating curves are highlighted to illustrate their impact on space heating thermodynamic behaviour and on the efficiency factors of the space heating system.Practical application: The study reveals that applying commercial building energy simulation software  is worthwhile to determine reliable performance predictions. Oversimplified building models, in particular when considering building thermal mass, are not capable of simulating the thermodynamic response of a building subjected to different control strategies. The application of different heating cuirves (linear and non-linear) to massless building models leaves the amount of mass flow rate delivered to the space heating unchanged when the building is subjected to sharp variations of the outdoor temperature.
  •  
9.
  • Brembilla, Christian, 1983-, et al. (author)
  • Transient model of a panel radiator
  • 2015
  • In: Energy, Science and Technology 2015. - Karlsruher, Germany : Karlsruher Institut für Technologie (KIT). ; , s. 321-321, s. 321-321
  • Conference paper (peer-reviewed)abstract
    • This paper shows a detailed transient model of a panel radiator considered as a system of multiple storageelements. The experiment records the temperature surface of the panel in the process of heating up. Thequalitative results of the experiment suggest the more appropriate technique for modelling this technology. The transient model performs the modelling with horizontal thermal capacitances connected in series. This modelcalculates the temperature of exhaust flow, heat emission towards indoor environment, temperature gradient onpanel surface, dead and balancing time identified numerically on the chart.
  •  
10.
  • Brembilla, Christian, 1983-, et al. (author)
  • Transient model of a panel radiator
  • 2015
  • In: Proceedings of BS2015. - India, Hyderabad : International Building Performance Simulation Association (IBPSA). ; , s. 2749-2756
  • Conference paper (peer-reviewed)abstract
    • This paper shows a transient model of a hydronic panel radiator modelled as a system of multiple storage elements. The experiment´s results suggest the more suitable technique for modelling this technology. The panel radiator is modelled numerically with eight thermal capacitance connected in series by keeping a memory of the heat injected in the thermal unit. The comparison of the performance among lumped steadystate models and transient model, in terms of heat emission and temperature of exhaust flow, shows the potential of the latter approach. To conclude, (1) the transient phase is essential for modelling stocky panels, and (2) this type of modelling has to be addressed for evaluating the performance of low energy buildings.
  •  
11.
  • Gasman, Danny, et al. (author)
  • MINDS Abundant water and varying C/O across the disk of Sz 98 as seen by JWST/MIRI
  • 2023
  • In: Astronomy and Astrophysics. - 0004-6361 .- 1432-0746. ; 679
  • Journal article (peer-reviewed)abstract
    • Context. The Mid-InfraRed Instrument (MIRI) Medium Resolution Spectrometer (MRS) on board the James Webb Space Telescope (JWST) allows us to probe the inner regions of protoplanetary disks, where the elevated temperatures result in an active chemistry and where the gas composition may dictate the composition of planets forming in this region. The disk around the classical T Tauri star Sz 98, which has an unusually large dust disk in the millimetre with a compact core, was observed with the MRS, and we examine its spectrum here.Aims. We aim to explain the observations and put the disk of Sz 98 in context with other disks, with a focus on the H2O emission through both its ro-vibrational and pure rotational emission. Furthermore, we compare our chemical findings with those obtained for the outer disk from Atacama Large Millimeter/submillimeter Array (ALMA) observations.Methods. In order to model the molecular features in the spectrum, the continuum was subtracted and local thermodynamic equilibrium (LTE) slab models were fitted. The spectrum was divided into different wavelength regions corresponding to H2O lines of different excitation conditions, and the slab model fits were performed individually per region.Results. We confidently detect CO, H2O, OH, CO2, and HCN in the emitting layers. Despite the plethora of H2O lines, the isotopo-logue (H2O)-O-18 is not detected. Additionally, no other organics, including C2H2, are detected. This indicates that the C/O ratio could be substantially below unity, in contrast with the outer disk. The H2O emission traces a large radial disk surface region, as evidenced by the gradually changing excitation temperatures and emitting radii. Additionally, the OH and CO2 emission is relatively weak. It is likely that H2O is not significantly photodissociated, either due to self-shielding against the stellar irradiation, or UV shielding from small dust particles. While H2O is prominent and OH is relatively weak, the line fluxes in the inner disk of Sz 98 are not outliers compared to other disks.Conclusions. The relative emitting strength of the different identified molecular features points towards UV shielding of H2O in the inner disk of Sz 98, with a thin layer of OH on top. The majority of the organic molecules are either hidden below the dust continuum, or not present. In general, the inferred composition points to a sub-solar C/O ratio (<0.5) in the inner disk, in contrast with the larger than unity C/O ratio in the gas in the outer disk found with ALMA.
  •  
12.
  •  
13.
  • Nair, Gireesh, et al. (author)
  • Comparative evaluation of city dwellers' perspectives on household energy use based on housing tenure : survey results from Northern Sweden
  • 2019. - 1
  • In: Cold climate HVAC 2018. - Switzerland : Springer Publishing Company. - 9783030006617 - 9783030006624 ; , s. 791-801
  • Conference paper (peer-reviewed)abstract
    • The successful implementation of energy efficiency measures in the residential sector will depend to a large extent on the attitudes and perceptions of the end-users since they are the final decision maker. The tenure of the housing could influence the building occupants' perspectives on energy issues. In this study we conducted a comparative evaluation of perspectives on energy use of three categories of households: those living in single family houses, tenants and owners' of apartment. The analysis is based on responses to a mail-in questionnaire by approximately 650 residents in Umeå, Sweden. Majority of the respondents believed that their annual household energy use is less. Residents in single-family houses, as compared to the other two types of tenure of the housing, were more likely to believe their heat energy use as high and likely to take actions to reduce the energy use. Financial incentives such as subsidy or lower interest rate were preferred by most of single-family homeowners (45%) to motivate them to take actions to reduce energy use. While personalized information to reduce energy use and lower interest rate and reduced rent are preferred by more residents in the other two categories. The implications for promoting energy efficient measures based on housing tenure is discussed.
  •  
14.
  • Olofsson, Thomas, 1968-, et al. (author)
  • Små steg har betydelse
  • 2015
  • In: Västerbottenskuriren. ; , s. 7-
  • Journal article (pop. science, debate, etc.)
  •  
15.
  • Olofsson, Thomas, 1968-, et al. (author)
  • Viktiga små steg för bättre klimat
  • 2014
  • In: Västerbottenskuriren. - : Västerbottenskuriren. - 1104-0246. ; , s. 6-
  • Journal article (pop. science, debate, etc.)
  •  
16.
  • Allard, Ingrid, 1986-, et al. (author)
  • A methodology to investigate the building energy performance gap
  • 2015
  • Other publication (other academic/artistic)abstract
    • In order to evaluate compliance with requirements on building energy performance, it is necessary to find strategies to process discrepancies from the results of forward simulations in the design stage and of measurements in the operated stage. The gap between designed performance and measured performance is referred to as the “performance gap”. It can be divided into a procurement gap (between intended design and verified performance) and an operational gap (between verified performance and non-normalized measurements).  In this work we introduced a methodology for performance gap analysis, based on separating the procurement- and operational gap. An important component to do this is calibrations of calculations using measured data. The suggested methodology allows for more detailed verifications of building energy performance and can be used to study how indicators reflect the performance gap. The proposed methodology is tested using data from a well-documented and measured operated single family building, in sub-arctic climate in Sweden.The indicators studied in the verification were carefully analyzed. The methodology was found reliable based on the obtained results and a sensitivity analysis. An overall observation is that the applicability of the methodology depends on the accuracy of the hybrid method. The accuracy of the performance gap analysis per definition depends on the available information of the operated building, and consequently to access to extensive measured data.
  •  
17.
  • Allard, Ingrid, 1986-, et al. (author)
  • Energy evaluation methods for  residential buildings in Nordic countries
  • 2012
  • In: Proceeding of the Technoport Conference. - : Elsevier.
  • Conference paper (peer-reviewed)abstract
    • To meet the goals of the directive 2010/31/EU on the energy performance of buildings, the building sector in Europe now faces a transition towards more energy efficient buildings. Research and development of new energy solutions and technology will be necessary for the transition and the importance of measuring and evaluating building energy performance increases. This paper attempts to review and evaluate different methods that are commonly used to analyze energy performance in residential buildings in Nordic countries, primarily in Sweden, Norway and Finland. A short international review of regulations is also included. Some advantages and disadvantages of each method are discussed, as well as commonly used methods in the three countries. Although the three Nordic countries have similar climate conditions and building traditions, the study shows that there exist relatively large variations in defining parameters related to energy performance in residential buildings, such as energy use, heated area, and climate zones. The outcome of the regulations could be investigated by adapting the codes on a selected set of buildings. Common analyzing methods, or parts of methods, are found to be used in several countries. These aspects may be considered in further work to develop more accurate and easily comparable methods to evaluate energy performance for residential buildings in cold climate.
  •  
18.
  • Allard, Ingrid, 1986-, et al. (author)
  • Energy evaluation of residential buildings : Performance gap analysis incorporating uncertainties in the evaluation methods
  • 2018
  • In: Building Simulation. - : Tsinghua University Press. - 1996-3599 .- 1996-8744. ; 11:4, s. 725-737
  • Journal article (peer-reviewed)abstract
    • Calculation and measurement-based energy performance evaluations of the same building often provide different results. This difference is referred as "the performance gap". However, a large performance gap may not necessarily mean that there are flaws in the building or deviations from the intended design. The causes for the performance gap can be analysed by calibrating the simulation model to measured data. In this paper, an approach is introduced for verifying compliance with energy performance criteria of residential buildings. The approach is based on a performance gap analysis that takes the uncertainties in the energy evaluation methods into consideration. The scope is to verify building energy performance through simulation and analysis of measured data, identifying any performance gap due to deviations from the intended design or flaws in the finished building based on performance gap analysis. In the approach, a simulation model is calibrated to match the heat loss coefficient of the building envelope [kWh/K] instead of the measured energy. The introduced approach is illustrated using a single-family residential building. The heat loss coefficient was found useful towards identifying any deviations from the intended design or flaws in the finished building. The case study indicated that the method uncertainty was important to consider in the performance gap analysis and that the proposed approach is applicable even when the performance gap appears to be non-existing.
  •  
19.
  • Allard, Ingrid, 1986-, et al. (author)
  • Energy performance criteria for residential buildings : A comparison of Finnish, Norwegian, Swedish, and Russian building codes
  • 2021
  • In: Energy and Buildings. - : Elsevier. - 0378-7788 .- 1872-6178. ; 250
  • Journal article (peer-reviewed)abstract
    • Building code are considered to be an effective policy tool to reduce energy use in buildings. In practice, national priorities influence the indicators and criteria adopted in the building codes. Consequently, neighbouring countries with similar climate conditions may use different criteria in their building codes to regulate the energy performance. In this paper, the energy performance criteria and their relative stringency in the latest residential building codes of Finland, Norway, Sweden and Russia are compared. The study is based on energy performance evaluations of one single-family building and one multi-family building, located in the north of Sweden. Both buildings complied with the Norwegian and Russian building code. However, the buildings did not comply with the specific fan power and heat loss criteria in the Finnish building code. Additionally, the single-family building did not comply with the specific primary energy and electric powerdemand criteria in the Swedish building code when heated by an electric heater. The national standard input data were found to have a large influence on the buildings’ compliance with the studied energy use criteria. Policy implications of the results are discussed.
  •  
20.
  • Allard Stolterman, Ingrid, 1986- (author)
  • Regulating energy performance of residential buildings in cold climate : a study of indicators, criteria, and evaluation methods
  • 2021
  • Doctoral thesis (other academic/artistic)abstract
    • Building energy performance has been important in Fennoscandia ever since the early vernacular houses, to combat the cold climate. Due to EU directive 2010/31/EU on the energy performance of buildings (EPBD recast), building energy performance has become even more relevant in northern Europe the last decade. Objectives for improving building energy performance may include reducing cost and CO2-emissions, increasing energy independency, and improving the indoor climate. Different indicators, criteria, and evaluations methods may be used to reach these objectives. This dissertation addresses indicators, criteria, and evaluation methods used to regulate energy performance of residential buildings in Sweden, Norway, Finland, and Russia. Four research objectives are covered: (RO1) comparing criteria and evaluation methods used to regulate energy performance of residential buildings in Sweden, Norway, and Finland, (RO2) studying the perspective of professionals with experience in building energy performance evaluation on (a) methods for evaluating envelope air leakage of residential buildings in Sweden and Finland and (b) potential energy performance indicators in the Swedish procurement process of multi-family buildings, (RO3) developing an approach for analysing the performance gap between design predictions and measurements that can be used to verify compliance with requirements on building energy use in practice, and (RO4) comparing the stringency of the energy performance criteria for residential buildings between the Swedish, Norwegian, Finnish, and Russian national building code. Many differences were found between how energy performance of residential buildings was regulated in the four countries. In Sweden, measurements were used more for evaluating building energy performance than in the other countries. As of 1st January 2020, the Finnish building code was characterized by its focus on the building heat loss and stringent energy performance criteria compared to the other countries. The Norwegian building code was characterized by a relatively narrow system perspective on energy performance, with no regulation of the energy production efficiency or energy source. The Russian building code also had a narrow system perspective but was also characterized by its focus on the form factor – the relationship between building volume and enclosing area. The practitioners wanted to minimize the influence from building operation and user behaviour on energy performance evaluations in the Swedish building procurement process of multi-family buildings. Hence, they preferred component-focused indicators or indicators with a narrow system boundary. An approach has been developed for analyzing the performance gap between design phase predictions and measurements. The approach can be used to verify the finished building’s energy performance, with minimal influence from occupant behavior and building operation.
  •  
21.
  • Andersson, Agnes, et al. (author)
  • Headache Before and After Endoscopic Transsphenoidal Pituitary Tumor Surgery: A Prospective Study
  • 2022
  • In: Journal of Neurological Surgery Part B-Skull Base. - : Georg Thieme Verlag KG. - 2193-6331 .- 2193-634X. ; 83:suppl. 2
  • Journal article (peer-reviewed)abstract
    • Objective Headache is a common symptom among patients with pituitary tumors, as it is in the general population. The aim of the study was to investigate headache as a symptom in patients with pituitary tumors before and 6 months after endoscopic transsphenoidal surgery (TSS). Design This is a prospective observational cohort study. Setting This study was conducted at university tertiary referral hospital. Participants A total of 110 adult patients underwent endoscopic TSS for pituitary tumors. Main Outcome Measures The Migraine Disability Assessment (MIDAS) questionnaire was used before and 6 months after surgery for the assessment of headache. Clinical variables with potential influence on headache were analyzed. Results Sixty-eight (62%) patients experienced headaches at least once during the 3 months before surgery. Thirty (27%) patients reported disabling headache before surgery, with younger age being an independent associated factor ( p <0.001). In patients with disabling headache before surgery, the median (interquartile range) MIDAS score improved from 78 (27-168) to 16 (2-145; p =0.049), headache frequency decreased from 45 (20-81) to 14 (4-35) days ( p =0.009), and headache intensity decreased from 6 (5-8) to 5 (4-7) ( p =0.011) after surgery. In total, 16 of the 30 (53%) patients reported a clinically relevant improvement and five (17%) a clinically relevant worsening. Four (5%) patients developed new disabling headache. No predictor for postoperative improvement of headache was identified. Conclusion In this prospective study, the results show that disabling headache improves following endoscopic TSS in a subset of patients with pituitary tumors. However, no predictive factors for improvement could be identified.
  •  
22.
  • Andersson, Staffan, 1952-, et al. (author)
  • Building performance based on measured data
  • 2011
  • In: World Renewable Energy Congress – Sweden, 8–13 May, 2011, Linköping, Sweden. - Linköping : Linköping University Electronic Press. - 9789173930703 ; , s. 899-906
  • Conference paper (peer-reviewed)abstract
    • With increasing liability for builders, the need for evaluation methods that focuses on the building’s performance and thus excludes the impact from residents’ behavior increases. This is not only of interest for new buildings but also when retrofitting existing buildings in order to reduce energy end-use. The investigation in this paper is based on extensive measurements on two fairly representative type of buildings, a single family building in Ekerö, Stockholm built 2000 and two apartment buildings in Umeå (1964) in order to extract key energy performance parameters such as the building’s heat loss coefficient, heat transfer via the ground and heat gained from the sun and used electricity. With access to pre-processed daily data from a 2-month periods, located close to the winter solstice, a robust estimate of the heat loss coefficient was obtained based on a regression analysis. For the single family building the variation was within 1% and for the two heavier apartment buildings an average variation of 2%, with a maximum of 4%, between different analyzed periods close to the winter solstice. The gained heating from the used electricity in terms of a gain factor could not be unambiguously extracted and therefore could only a range for the heat transfer via ground be estimated. The estimated range for the transfer via ground for the two apartment buildings were in very good agreement with those calculated according to EN ISO 13 370 and corresponded to almost 10% of the heating demand at the design temperature. For the single family building with an insulated slab and parts of the walls below ground level, the calculations gave slightly higher transfer than what was obtained from the regression analysis. For the estimated gained solar radiation no comparison has been possible to make, but the estimated gain exhibited an expected correlation with the global solar radiation data that was available for the two apartment buildings.
  •  
23.
  •  
24.
  •  
25.
  • Azizi, Shoaib, 1989- (author)
  • A multi-method assessment to support energy efficiency decisions in existing residential and academic buildings
  • 2021
  • Doctoral thesis (other academic/artistic)abstract
    • Rapid decarbonization of building stock is essential for the energy transition required to mitigate climate change and limit the global temperature rise below 1.5 °C. The decision-making for the adoption of energy efficiency measures (EEMs) is often complex and involves lasting consequences and risks. The strategy to direct and support the decision makers can significantly increase the adoption rate of EEMs in buildings. This Ph.D. project focuses on facilitating sustainability improvement in buildings by supporting the decision makers who are accountable for the consequences of adopting the EEMs. Energy efficiency improvement is decided and managed differently in various types of buildings and contexts and encounters different challenges and opportunities. Accordingly, it is required to understand the needs to select adequate strategies and to devise effective supporting interventions for energy efficiency improvement.The owners of single-family houses are often the occupants who are in charge of the most decisions to improve energy efficiency in their dwellings. The situation is rather different in multi-family buildings and academic buildings in which organizational management adds more complexity and the decisions affect various stakeholders. The studies in this project are based on qualitative and quantitative data collected from single-family houses, multi-family buildings, and university buildings in northern Sweden. Surveys were used to elicit the decision makers' perceptions of different types of buildings. Moreover, sensor data from university buildings were used in the case studies to develop informative metrics for space use efficiency and to analyze the effect of sensor positioning on monitored data.The initial work involved understanding the opportunities and challenges of improving energy efficiency in buildings and the tradeoffs between the perceived benefits and barriers. This part of the thesis provided the foundation and inspiration for the rest of the project, including investigating how to bundle several measures and use information and communication technologies (ICT) for building sustainability. The findings show lack of information and evidence that could justify the beneficial outcomes of EEMs is a major barrier for effective decision-making. Clear information on potential improvements allows sharing the responsibilities among different stakeholders and increases the management capacity to handle projects and adopt EEMs. Using feedback tools (for example, space use and/or energy use visualizations) might be an effective strategy to influence decision makers.Various studies incorporated in this multidisciplinary Ph.D. thesis develop and investigate strategies to support decision makers to improve energy efficiency in buildings. The findings provide insights to policymakers and businesses to devise intervention strategies for energy efficiency in buildings.
  •  
26.
  • Azizi, Shoaib, 1989-, et al. (author)
  • Adoption of Energy Efficiency Measures in Renovation of Single-Family Houses : A Comparative Approach
  • 2020
  • In: Energies. - : MDPI. - 1996-1073. ; 13:22
  • Journal article (peer-reviewed)abstract
    • Inclusion of energy efficiency measures (EEMs) in the renovation of the single-family housing stock can unlock the potential for much-needed energy efficiency to tackle climate change. Energy renovation (ER) in single-family houses is often promoted as an aggregate process, and EEMs are treated homogenously without sufficient attention to their differences. This study applies a comparative analysis on common EEMs using chi-square test to investigate the influence of factors already found affecting the implementation of ER. This paper addresses the “personal” and “house-related” factors influencing the adoption of EEMs regardless of motives or barriers leading the adopters’ decisions. This strategy is useful to highlight the contexts leading to an increase in the adoption rate of different EEMs. The analysis is based on a questionnaire survey mailed in spring 2017 to 1550 single-family homeowners in the northern region of Sweden. Approximately 60% of respondents showed interest in adopting at least one EEM if they implement a major renovation. About 46% of respondents stated to have at least one indoor environmental problem (IEP) in their houses, and IEPs are found to have significant relations with homeowners’ interest to adopt several different EEMs. The policy implications related to different EEMs are discussed.
  •  
27.
  • Azizi, Shoaib, 1989-, et al. (author)
  • Analysing the house-owners’ perceptions on benefits and barriers of energy renovation in Swedish single-family houses
  • 2019
  • In: Energy and Buildings. - : Elsevier. - 0378-7788 .- 1872-6178. ; 198, s. 187-196
  • Journal article (peer-reviewed)abstract
    • Single-family houses offer a large potential for energy savings by energy renovation (ER). Homeowners’ motivation to implement ER derives from the benefits and barriers they perceive. Benefits are the positive consequences that can motivate homeowners to act and barriers are the challenges that demotivate them to undertake ER. Different benefits and barriers do not homogenously affect every homeowner. Identifying motivating benefits and demotivating barriers for each specific group among homeowners can shed lights on ER decision-making and enable policies that are more effective. The objective of this study is to contextualize the implementation of ER by understanding how the perceived benefits and barriers influence homeowners. This study links the expected consequences, which are benefits and barriers to the influential factors on ER, which are used to group the homeowners.The analysis is based on a questionnaire survey mailed to 1550 owners of single-family houses in northern Sweden. The perceptions of homeowners on benefits and barriers of ER are significantly different between the groups that are motivated and unmotivated to implement ER. Despite the perceived importance of some of the benefits such as energy cost reduction, they may not be determinative for the homeowners’ decision to undertake ER. The homeowners are more likely to implement ER for reasons other than energy use reduction such as for improving the indoor environment. The barriers such as the difficulty of finding a low-interest loan and reliable information sources are found to impede the intention to implement ER among different groups. Policy implications to facilitate ER in single-family houses are discussed.
  •  
28.
  • Azizi, Shoaib, et al. (author)
  • Application of Internet of Things in academic buildings for space use efficiency using occupancy and booking data
  • 2020
  • In: Building and Environment. - : Elsevier. - 0360-1323 .- 1873-684X. ; 186
  • Journal article (peer-reviewed)abstract
    • Environmental sustainability in academic buildings can be improved with management interventions such as improving space use efficiency supported by large data from the Internet of Things (IoT). Due to the potentials, the interest in the use of IoT tools for facility management is high among universities. However, empirical studies on this topic are scarce. To address the knowledge gap in this area, this study proposes and examines a process model with steps to measure space use and to improve space use efficiency by IoT tools in academic buildings. The applicability of the model is investigated in 8 lecture halls in a university building by using occupancy and booking data from IoT tools. Four space use indicators are developed to visualize the data and quantify space use, and based on them, the strategies and interventions for space use efficiency are proposed and discussed.
  •  
29.
  • Azizi, Shoaib, et al. (author)
  • Application of occupancy and booking information to optimize space and energy use in higher education institutions
  • 2020
  • In: E3S Web of Conferences. - : EDP Sciences. - 2267-1242. ; 172
  • Journal article (peer-reviewed)abstract
    • Building in higher education institutions (HEIs) are characterized as energy intensive Experience from practice showing large discrepancies between predicted and actual energy performance. The deviation can sometimes reach 100%. Explanations often originate from occupant’s behaviour along with building operation. IoT-based smart tools can provide extensive information about building usage to improve the building management, often associates with opportunities, for significant energy saving. The analysis in this study investigate space use based on occupancy and booking information in eight different lecture rooms at Umeå University. The results suggest interventions for significant saving potentials, such as modification of access permission and closing down redundant lecture rooms.
  •  
30.
  • Azizi, Shoaib, 1989-, et al. (author)
  • Comparative Study of Influential Factors on Implementation of Energy Efficiency Measures in Single-Family Houses in Cold Climate
  • 2018
  • Conference paper (peer-reviewed)abstract
    • A combination of factors, which include occupants and building related aspects, could motivate homeowners to implement energy renovation (ER). This study applies a comparative approach to assess perspectives of single-family homeowners towards different energy efficiency measures (EEMs). The aim is to unveil the factors that are effective on the residents’ attitude and decision making to implement an EEM or a set of EEMs. The analysis is based on a questionnaire survey conducted during spring 2017 among1550 owners of single-family houses in seven municipalities in northern Sweden. Approximately, 35% of respondents expressed their interest to install energy efficient household appliances and solar photovoltaic (PV) systems. The analysis suggests significant relations between the homeowners’ interest to implement thermal envelope measures and the quality of the house such as age and indoor environmental problems such as cold surfaces. The group of respondents, who reported their heating cost to be high, are more likely to be interested in implementing thermal envelope measures than other measures such as HVAC. Several socio-economic factors are found to be significantly related with homeowners’ interest to implement EEMs.
  •  
31.
  • Azizi, Shoaib, 1989-, et al. (author)
  • Demand-controlled energy systems in commercial and institutional buildings : a review of methods and potentials
  • 2019
  • In: eceee 2019 Summer Study on energy efficiency. - : European Council for an Energy Efficient Economy (ECEEE). - 9789198387858 - 9789198387841 ; , s. 1444-1450
  • Conference paper (peer-reviewed)abstract
    • Heating, ventilation and air-conditioning (HVAC) are by farthe most energy intensive systems in commercial and institutionalbuildings with office spaces. This makes HVAC systemsattractive targets for energy efficiency improvement. New technologicaladvancements can play significant role on improvingenergy efficiency. Such advancements have been also emergedin form of novel management and control strategies, whichmight lead to considerable energy savings with relatively minorinvestments. This paper evaluates demand control HVAC andlighting to assess the energy saving potential of upgrading theconventional building energy systems.This paper provides a summary of different methods and occupancydetection technologies. A range of technologies andmethods are covered that vary in complexity, limitations andenergy saving potential. Additional benefits such as demandresponse are evaluated and other emerging applications arediscussed. Based on the review of methods and potentials, thepaper assesses the state of the art in demand controlled energysystems and suggests areas for further research.
  •  
32.
  •  
33.
  • Azizi, Shoaib, et al. (author)
  • Effects of Positioning of Multi-Sensor Devices on Occupancy and Indoor Environmental Monitoring in Single-Occupant Offices
  • 2021
  • In: Energies. - : MDPI. - 1996-1073. ; 14:19
  • Journal article (peer-reviewed)abstract
    • The advancements in sensor and communication technologies drive the rapid developments in the applications of occupancy and indoor environmental monitoring in buildings. Currently, the installation standards for sensors are scarce and the recommendations for sensor positionings are very general. However, inadequate sensor positioning might diminish the reliability of sensor data, which could have serious impacts on the intended applications such as the performance of demand-controlled HVAC systems and their energy use. Thus, there is a need to understand how sensor positioning may affect the sensor data, specifically when using multi-sensor devices in which several sensors are being bundled together. This study is based on the data collected from 18 multi-sensor devices installed in three single-occupant offices (six sensors in each office). Each multi-sensor device included sensors to measure passive infrared (PIR) radiation, temperature, CO2, humidity, and illuminance. The results show that the positions of PIR and CO2 sensors significantly affect the reliability of occupancy detection. The typical approach of positioning the sensors on the ceiling, in the middle of offices, may lead to relatively unreliable data. In this case, the PIR sensor in that position has only 60% accuracy of presence detection. Installing the sensors under office desks could increase the accuracy of presence detection to 84%. These two sensor positions are highlighted in sensor fusion analysis as they could reach the highest accuracy compared to other pairs of PIR sensors. Moreover, sensor positioning can affect various indoor environmental parameters, especially temperature and illuminance measurements.
  •  
34.
  • Barrado, David, et al. (author)
  • 15NH3 in the atmosphere of a cool brown dwarf
  • 2023
  • In: Nature. - 0028-0836 .- 1476-4687. ; 624:7991, s. 263-266
  • Journal article (peer-reviewed)abstract
    • Brown dwarfs serve as ideal laboratories for studying the atmospheres of giant exoplanets on wide orbits, as the governing physical and chemical processes within them are nearly identical. Understanding the formation of gas-giant planets is challenging, often involving the endeavour to link atmospheric abundance ratios, such as the carbon-to-oxygen (C/O) ratio, to formation scenarios. However, the complexity of planet formation requires further tracers, as the unambiguous interpretation of the measured C/O ratio is fraught with complexity. Isotope ratios, such as deuterium to hydrogen and 14N/15N, offer a promising avenue to gain further insight into this formation process, mirroring their use within the Solar System. For exoplanets, only a handful of constraints on 12C/13C exist, pointing to the accretion of 13C-rich ice from beyond the CO iceline of the disks. Here we report on the mid-infrared detection of the 14NH3 and 15NH3 isotopologues in the atmosphere of a cool brown dwarf with an effective temperature of 380 K in a spectrum taken with the Mid-Infrared Instrument (MIRI) of JWST. As expected, our results reveal a 14N/15N value consistent with star-like formation by gravitational collapse, demonstrating that this ratio can be accurately constrained. Because young stars and their planets should be more strongly enriched in the 15N isotope, we expect that 15NH3 will be detectable in several cold, wide-separation exoplanets. 
  •  
35.
  •  
36.
  • Cheng, Xiaogang, et al. (author)
  • A Contactless Measuring Method of Skin Temperature based on the Skin Sensitivity Index and Deep Learning
  • 2019
  • In: Applied Sciences. - Switzerland : MDPI. - 2076-3417 .- 1454-5101. ; 9:7
  • Journal article (peer-reviewed)abstract
    • Featured Application The NISDL method proposed in this paper can be used for real time contactless measuring of human skin temperature, which reflects human body thermal comfort status and can be used for control HVAC devices. Abstract In human-centered intelligent building, real-time measurements of human thermal comfort play critical roles and supply feedback control signals for building heating, ventilation, and air conditioning (HVAC) systems. Due to the challenges of intra- and inter-individual differences and skin subtleness variations, there has not been any satisfactory solution for thermal comfort measurements until now. In this paper, a contactless measuring method based on a skin sensitivity index and deep learning (NISDL) was proposed to measure real-time skin temperature. A new evaluating index, named the skin sensitivity index (SSI), was defined to overcome individual differences and skin subtleness variations. To illustrate the effectiveness of SSI proposed, a two multi-layers deep learning framework (NISDL method I and II) was designed and the DenseNet201 was used for extracting features from skin images. The partly personal saturation temperature (NIPST) algorithm was use for algorithm comparisons. Another deep learning algorithm without SSI (DL) was also generated for algorithm comparisons. Finally, a total of 1.44 million image data was used for algorithm validation. The results show that 55.62% and 52.25% error values (NISDL method I, II) are scattered at (0 degrees C, 0.25 degrees C), and the same error intervals distribution of NIPST is 35.39%.
  •  
37.
  • Cheng, Xiaogang, et al. (author)
  • A pilot study of online non-invasive measuring technology based on video magnification to determine skin temperature
  • 2017
  • In: Building and Environment. - : Elsevier. - 0360-1323 .- 1873-684X. ; 121, s. 1-10
  • Journal article (peer-reviewed)abstract
    • Much attention was paid on human centered design strategies for environmental control systems of indoor built environments. The goal is to achieve thermally comfortable, healthy and safe working or living environments in energy efficient manners. Normally building Heating, Ventilation and Air Conditioning (HVAC) systems have fixed operating settings, which can't satisfy human thermal comfort requirements under transient and non-uniform indoor thermal environments. Therefore, human thermal physiology signal such as skin temperature, which can reflect human body thermal sensation, has to be measured over time. Several trials have been performed by minimizing measuring sensors such as i-Button and mounting measuring sensors into wearable devices such as glasses. Infrared thermography technology has also been tried to achieve non-invasive measurements. However, it would be much more convenient and feasible if normal computer camera could record images, which could be used to obtain human thermal physiology signals. In this study, skin temperature of hand back, which has a high density of blood vessels and is normally not covered by clothing, was measured by i-button sensors. Images recorded by normal camera were amplified to analyzing skin temperature variation, which are impossible to see with naked eyes. The agreement between i-button sensor measuring results and image magnification results demonstrated the possibility of non-invasive measuring technology by image magnification. Partly personalized saturation-temperature model (T = 96.5 × S + bi) can be used to predict skin temperatures for young East Asia females.
  •  
38.
  • Cheng, Xiaogang, et al. (author)
  • A variational approach to atmospheric visibility estimation in the weather of fog and haze
  • 2018
  • In: Sustainable cities and society. - : Elsevier. - 2210-6707. ; 39, s. 215-224
  • Journal article (peer-reviewed)abstract
    • Real-time atmospheric visibility estimation in foggy and hazy weather plays a crucial role in ensuring traffic safety. Overcoming the inherent drawbacks with traditional optical estimation methods, like limited sampling volume and high cost, vision-based approaches have received much more attention in recent research on atmospheric visibility estimation. Based on the classical Koschmieder's formula, atmospheric visibility estimation is carried out by extracting an inherent extinction coefficient. In this paper we present a variational framework to handle the nature of time-varying extinction coefficient and develop a novel algorithm of extracting the extinction coefficient through a piecewise functional fitting of observed luminance curves. The developed algorithm is validated and evaluated with a big database of road traffic video from Tongqi expressway (in China). The test results are very encouraging and show that the proposed algorithm could achieve an estimation error rate of 10%. More significantly, it is the first time that the effectiveness of Koschmieder's formula in atmospheric visibility estimation was validated with a big dataset, which contains more than two million luminance curves extracted from real-world traffic video surveillance data.
  •  
39.
  • Cheng, Xiaogang, et al. (author)
  • Contactless sleep posture measurements for demand-controlled sleep thermal comfort : a pilot study
  • 2022
  • In: Indoor Air. - : Wiley-Blackwell. - 0905-6947 .- 1600-0668. ; 32:12
  • Journal article (peer-reviewed)abstract
    • Thermal comfort during sleep is essential for both sleep quality and human health while sleeping. There are currently few effective contactless methods for detecting the sleep thermal comfort at any time of day or night. In this paper, a vision-based detection approach for human thermal comfort while sleeping was proposed, which is intended to avoid overcooling/overheating supply, meet the thermal comfort needs of human sleep, and improve human sleep quality and health. Based on 438 valid questionnaire surveys, 10 types of thermal comfort sleep postures were summarized. By using a large number of data captured, a fundamental framework of detection algorithm was constructed to detect human sleeping postures, and corresponding weighting model was established. A total of 2.65 million frames of posture data in natural sleep status were collected, and thermal comfort-related sleep postures dataset was created. Finally, the robustness and effectiveness of the proposed algorithm were validated. The validation results show that the sleeping posture and human skeleton keypoints can be used for estimating sleeping thermal comfort, and the the quilt coverage area can be fused to improve the detection accuracy.
  •  
40.
  • Cheng, Xiaogang, et al. (author)
  • NIDL: A pilot study of contactless measurement of skin temperature for intelligent building
  • 2019
  • In: Energy and Buildings. - : Elsevier. - 0378-7788 .- 1872-6178. ; 198, s. 340-352
  • Journal article (peer-reviewed)abstract
    • Human thermal comfort measurement plays a critical role in giving feedback signals for building energy efficiency. A contactless measuring method based on subtleness magnification and deep learning (NIDL) was designed to achieve a comfortable, energy efficient built environment. The method relies on skin feature data, e.g., subtle motion and texture variation, and a 315-layer deep neural network for constructing the relationship between skin features and skin temperature. A physiological experiment was conducted for collecting feature data (1.44 million) and algorithm validation. The contactless measurement algorithm based on a partly-personalized saturation temperature model (NIPST) was used for algorithm performance comparisons. The results show that the mean error and median error of the NIDL are 0.476 °C and 0.343°C which is equivalent to accuracy improvements of 39.07 % and 38.76 %, respectively.
  •  
41.
  • Feng, Kailun, et al. (author)
  • Energy-efficient retrofitting with incomplete building information : a data-driven approach
  • 2022
  • In: E3S web of conferences. - : EDP Sciences.
  • Conference paper (peer-reviewed)abstract
    • The high-performance insulations and energy-efficient HVAC have been widely employed as energy-efficient retrofitting for building renovation. Building performance simulation (BPS) based on physical models is a popular method to estimate expected energy savings for building retrofitting. However, many buildings, especially the older building constructed several decades ago, do not have full access to complete information for a BPS method. To address this challenge, this paper proposes a data-driven approach to support the decision-making of building retrofitting under incomplete information. The data-driven approach is constructed by integrating backpropagation neural networks (BRBNN), fuzzy C-means clustering (FCM), principal component analysis (PCA), and trimmed scores regression (TSR). It is motivated by the available big data sources from real-life building performance datasets to directly model the retrofitting performances without generally missing information, and simultaneously impute the case-specific incomplete information. This empirical study is conducted on real-life buildings in Sweden. The result indicates that the approach can model the performance ranges of energy-efficient retrofitting for family houses with more than 90% confidence. The developed approach provides a tool to predict the performance of individual buildings from different retrofitting measures, enabling supportive decision-making for building owners with inaccessible complete building information, to compare alternative retrofitting measures.
  •  
42.
  • Fischl, Geza, et al. (author)
  • Design av terapeutiska miljöer
  • 2012
  • In: Byggnadsrelaterad ohälsa i Kvarkenregionen. - Vasa : Yrkeshögskolan Novia. - 9789525839364 ; , s. 103-110
  • Book chapter (other academic/artistic)abstract
    • Terapeutiska miljöer kan ha en kraftfull, läkande effekt på patienter – de sänker stressnivån vilket gör att patienternas medicinska tillstånd förbättras. Entydiga forskningsresultat visar att t.ex. vistelse i naturen, motion, fysisk rörelse och förbättrade sociala aktiviteter gör att patienters återhämtningsförmåga stärks och stressnivån sjunker. De terapeutiska miljöerna ger en ökad känsla av kontroll, stärkt integritet och förbättrat social stöd. Genom att erbjuda positiv stimulans, såsom konst eller musik, förstärks den goda upplevelsen ytterligare. Trots att man i olika evidensbaserade forskningsstudier bevisat att terapeutiska miljöer har positiv inverkan på patienters hälsa och välbefinnande är dessa miljöer mindre kända hos allmänheten, som därför inte heller efterfrågar dem i samband med vård. Förmodligen är utbildning av allmänheten en framkomlig väg att för att höja medvetenheten om terapeutiska miljöers hälsofrämjande effekt.
  •  
43.
  • Glader, Annika, et al. (author)
  • Fuktskadade byggnader : kompetensutveckling inom byggbranschen
  • 2015
  • Reports (other academic/artistic)abstract
    • De många olika benämningarna på aktörer i byggbranschen har förorsakat problem för beställarna vid valet av kompetenta utredare för utredning av inomhusmiljöproblem. Även för utbildare och studerande har överlappningarna i utbildningssystemen och avsaknaden av behörighetsgränser förorsakat problem. För att svara mot kompetensbehovet på fältet har man hittills fått förlita sig på frivilliga, avgiftsbelagda fortbildningar. Detta system har dock inte klarat av att tillgodose behovet. I Finland har man inom åtgärdsprogrammet ”Fukt- och mögeltalko” haft en arbetsgrupp som tagit fram en plan för hur man borde utveckla utbildningen och kompetensen för de som jobbar med utredning och renovering av fukt- och mögelskadade byggnader. De flesta yrkeshögskolor med byggutbildning har någon form av undervisning om inomhusmiljö och renovering även om antalet lärundervisningstimmar varierar stort. Några skolor har redan idag tillräckligt omfattande utbildning för att motsvara några av de nya förslagen på kompetenskrav. Yrkeshögskolan Novia ansvarar för den svenskspråkiga utbildningen av byggnadsingenjörer och byggmästare i Finland och har inom TEMA-projektet påbörjat utvecklingen av svenskspråkigt utbildningsmaterial och -strategier.
  •  
44.
  • Hallén, Tobias, et al. (author)
  • Circulating brain injury biomarkers increase after endoscopic surgery for pituitary tumors.
  • 2021
  • In: Journal of clinical neuroscience : official journal of the Neurosurgical Society of Australasia. - : Elsevier BV. - 1532-2653. ; 89, s. 113-121
  • Journal article (peer-reviewed)abstract
    • Pituitary tumors and subsequent treatment with endoscopic transsphenoidal surgery (ETSS) may cause injury to suprasellar structures, causing long-term fatigue and neurocognitive impairment. A method to quantify brain injury after ETSS is not available. In this prospective, exploratory study of patients undergoing ETSS for pituitary tumors, a novel approach to detect possible neuronal damage is presented. Plasma concentrations of brain injury biomarkers (glial fibrillary acidic protein [GFAP], tau, and neurofilament light [NFL]) were measured the day before surgery, immediately after surgery, at day 1 and 5, and at 6 and 12months after surgery, using enzyme-linked immunosorbent assays. The association between the increase of biomarkers with preoperative tumor extension and postoperative patient-perceived fatigue was evaluated. Suprasellar tumor extension was assessed from MRI scans, and self-perceived fatigue was assessed using the Multidimensional Fatigue Inventory before and 6months after surgery. Thirty-five patients were included in the analysis. Compared to baseline, GFAP showed a maximal increase at day 1 after surgery (p=0.0005), tau peaked postoperatively on the day of surgery (p=0.019), and NFL reached its maximum at day 5 after surgery (p<0.0001). The increase in GFAP correlated with preoperative chiasmal compression (p=0.020). The increase in tau was correlated with preoperative chiasmal (p=0.011) and hypothalamus compression (p=0.016), and fatigue score 6months after surgery (p=0.016). In conclusion, the concentrations of brain injury biomarkers in blood increased after ETSS for pituitary tumors. The results indicate that postoperative plasma GFAP and tau might reflect astroglial and neuronal damage after ETSS.
  •  
45.
  • Hallén, Tobias, et al. (author)
  • Sinonasal Symptoms and Self-Reported Health before and after Endoscopic Pituitary Surgery-A Prospective Study
  • 2022
  • In: Journal of Neurological Surgery, Part B: Skull Base. - : Georg Thieme Verlag KG. - 2193-634X .- 2193-6331. ; 83:suppl. 2
  • Journal article (peer-reviewed)abstract
    • © 2021 Thieme Medical Publishers, Inc.. All rights reserved. Objectives Despite the limited invasiveness of endoscopic transsphenoidal surgery (ETSS), some degree of nasal structure destruction is unavoidable. Our objective was to evaluate sinonasal morbidity and self-reported health before and 6 months after ETSS for pituitary tumors, and to identify possible predictive factors for deterioration in sinonasal health. Design Prospective observational cohort study. Setting University tertiary referral hospital. Participants Totally 109 consecutive adult patients undergoing ETSS for pituitary tumors between 2015 and 2019. Main Outcome Measures Sinonasal symptoms and self-reported health before and 6 months after ETSS, assessed by the Sinonasal Outcome Test (SNOT-22) and the EQ-5D questionnaire. Predictive factors for postoperative deterioration in sinonasal symptoms. Results The overall SNOT-22 score did not change, but the score of the rhinologic domain of SNOT-22 worsened from 6.0 ± 5.9 before to 8.0 ± 7.4 6 months after surgery (p = 0.011). The EQ-5D visual analog scale improved from 64.0 ± 22.9 before to 71.1 ± 18.7 6 months after surgery (p = 0.00088). Univariate and multivariable regression analyses showed that prior sinonasal surgery was associated with a significant worsening in rhinologic symptoms 6 months after surgery (p = 0.046 and p = 0.020, respectively). Conclusions Although self-reported overall health improved, significant deterioration of rhinologic symptoms was seen 6 months after ETSS. This information is important for preoperative patient counselling. Further refinement of the surgical technique and follow-up strategies to reduce postoperative sinonasal morbidity could be of value, especially in patients who have undergone prior sinonasal surgery.
  •  
46.
  • Hrastinski, Stefan, 1980-, et al. (author)
  • Critical Imaginaries and Reflections on Artificial Intelligence and Robots in Postdigital K-12 Education
  • 2019
  • In: Postdigital Science and Education. - : Springer Science and Business Media LLC. - 2524-485X .- 2524-4868 .- 2662-5326. ; 1:2, s. 427-445
  • Journal article (peer-reviewed)abstract
    • It is commonly suggested that emerging technologies will revolutionize education. In this paper, two such emerging technologies, artificial intelligence (AI) and educational robots (ER), are in focus. The aim of the paper is to explore how teachers, researchers and pedagogical developers critically imagine and reflect upon how AI and robots could be used in education. The empirical data were collected from discussion groups that were part of a symposium. For both AI and ERs, the need for more knowledge about these technologies, how they could preferably be used, and how the emergence of these technologies might affect the role of the teacher and the relationship between teachers and students, were outlined. Many participants saw more potential to use AI for individualization as compared with ERs. However, there were also more concerns, such as ethical issues and economic interests, when discussing AI. While the researchers/developers to a greater extent imagined ideal future technology-rich educational practices, the practitioners were more focused on imaginaries grounded in current practice.
  •  
47.
  • Hu, Siying, et al. (author)
  • A data-driven exploration of the relations between occupant behaviors and comfort performances of energy-efficient measures
  • 2023
  • In: ICCREM 2023. - : American Society of Civil Engineers (ASCE). - 9780784485217 ; , s. 592-604
  • Conference paper (peer-reviewed)abstract
    • Energy-efficient building retrofitting plays a crucial role in reducing energy consumption and carbon emissions within the building sector. Energy-efficient retrofitting brings about changes in the built environment and it could influence the occupant behaviors. Additionally, occupant behaviors, in turn, alter the indoor environment, thereby affecting the comfort performance of the building after retrofitting. To explore this intricate relation between occupant behaviors and comfort performances of energy-efficient measures, this paper employs a data-driven approach to compile a comprehensive dataset encompassing occupant behaviors, energy-efficient measures, and associated indoor comfort of an office building in Umeå University, Sweden. Multiple binary logistic regression is applied to quantify the relationship between occupant behaviors and comfort performances of energy-efficient measures. The findings of this study hold significant value, providing guidance for occupants in adapting to energy-efficient measures while also informing future retrofitting implementation.
  •  
48.
  • Hållbara hus i kallt klimat : 31 hus från Finland i öster till Kanada i väster
  • 2018
  • Editorial collection (other academic/artistic)abstract
    • Boken beskriver hur hållbar arkitektur kan vara utformad i subarktiskt och arktiskt klimat. Detta visas genom 31 exempel på hållbart byggande i Finland, Sverige, Norge, Svalbard, Island, Grönland, Kanada och USA. Projekten presenteras ur sex hållbarhetsperspektiv - energi, material, återbruk, platsen, klimat och funktion. Varje hus presenteras med bilder och arkitektens beskrivning av huset. Varje projekt har även text på engelska.
  •  
49.
  •  
50.
  • Jakobsson, Sofie, 1968, et al. (author)
  • Extended Support Within a Person-Centered Practice After Surgery for Patients With Pituitary Tumors: Protocol for a Quasiexperimental Study.
  • 2020
  • In: JMIR research protocols. - : JMIR Publications Inc.. - 1929-0748. ; 9:7
  • Journal article (peer-reviewed)abstract
    • Patients with pituitary tumors often live with lifelong consequences of their disease. Treatment options include surgery, radiotherapy, and medical therapy. Symptoms associated with the tumor or its treatment affect several areas of life. Patients need to adhere to long-term contact with both specialist and general health care providers due to the disease, complex treatments, and associated morbidity. The first year after pituitary surgery constitutes an important time period, with medical evaluations after surgery and decisions on hormonal substitution. The development and evaluation of extended patient support during this time are limited.The aim of this study is to evaluate whether support within a person-centered care practice increases wellbeing for patients with pituitary tumors. Our main hypothesis is that the extended support will result in increased psychological wellbeing compared with the support given within standard of care. Secondary objectives are to evaluate whether the extended support, compared with standard care, will result in (1) better health status, (2) less fatigue, (3) higher satisfaction with care, (4) higher self-efficacy, (5) increased person-centered content in care documentation, and (6) sustained patient safety.Within a quasiexperimental design, patients diagnosed with a pituitary tumor planned for neurosurgery are consecutively included in a pretest-posttest study performed at a specialist endocrine clinic. The control group receives standard of care after surgery, and the interventional group receives structured patient support for 1 year after surgery based on person-centeredness covering self-management support, accessibility, and continuity. A total of 90 patients are targeted for each group.Recruitment into the control group was performed between Q3 2015 and Q4 2017. Recruitment into the intervention group started in Q4 2017 and is ongoing until Q4 2020. The study is conducted according to the Declaration of Helsinki, and the protocol has received approval from a regional ethical review board.This study entails an extensive intervention constructed in collaboration between clinicians, patients, and researchers that acknowledges accessibility, continuity, and self-management support within person-centeredness. The study has the potential to compare standard care to person-centered practice adapted specifically for patients with pituitary tumors and evaluated with a combination of patient-reported outcomes and patient-reported experience measures. Following the results, the person-centered practice may also become a useful model to further develop and explore person-centered care for patients with other rare, lifelong conditions.Researchweb.org. https://www.researchweb.org/is/sverige/project/161671.DERR1-10.2196/17697.
  •  
Skapa referenser, mejla, bekava och länka
  • Result 1-50 of 155
Type of publication
journal article (75)
conference paper (55)
doctoral thesis (6)
research review (6)
reports (4)
editorial collection (2)
show more...
book (2)
other publication (2)
licentiate thesis (2)
artistic work (1)
book chapter (1)
show less...
Type of content
peer-reviewed (124)
other academic/artistic (27)
pop. science, debate, etc. (4)
Author/Editor
Olofsson, Thomas, 19 ... (138)
Nair, Gireesh (26)
Yang, Bin (24)
Andersson, Staffan, ... (24)
Lu, Weizhuo, Profess ... (11)
Puttige, Anjan Rao, ... (9)
show more...
Brembilla, Christian ... (9)
Soleimani-Mohseni, M ... (9)
Cheng, Xiaogang (9)
Li, Haibo (7)
Östin, Ronny (7)
Fransson, Åke (7)
Feng, Kailun (7)
Azizi, Shoaib, 1989- (6)
Azizi, Shoaib (6)
Johannsson, Gudmundu ... (5)
Skoglund, Thomas, 19 ... (5)
Olsson, Daniel S, 19 ... (5)
Allard, Ingrid, 1986 ... (5)
Olofsson, Thomas, Pr ... (5)
Jakobsson, Sofie, 19 ... (5)
Sjögren, Jan-Ulric, ... (5)
Östin, Ronny, 1958- (5)
Hallén, Tobias (4)
Jakobsson Ung, Eva, ... (4)
Zhang, Ying (4)
Rabiee, Ramtin (4)
Olofsson, Ann-Charlo ... (4)
Absil, Olivier (3)
Boccaletti, Anthony (3)
Olofsson, Göran, 194 ... (3)
Ragnarsson, Oskar, 1 ... (3)
Henning, Thomas (3)
Östlin, Göran, 1968- (3)
Eriksson, Ola (3)
Mueller, Michael (3)
Farahmand, Dan (3)
Bergquist, Henrik, 1 ... (3)
Barrado, David (3)
Argyriou, Ioannis (3)
Lagage, Pierre-Olivi ... (3)
Vandenbussche, Bart (3)
Bouwman, Jeroen (3)
Lahuis, Fred (3)
Scheithauer, Silvia (3)
Colina, Luis (3)
van Dishoeck, Ewine ... (3)
Wright, Gillian (3)
Li, Zhe (3)
Man, Qingpeng (3)
show less...
University
Umeå University (144)
Royal Institute of Technology (10)
University of Gothenburg (7)
Halmstad University (6)
University of Gävle (6)
Högskolan Dalarna (5)
show more...
Stockholm University (3)
Linköping University (2)
Uppsala University (1)
University West (1)
Lund University (1)
Mid Sweden University (1)
Chalmers University of Technology (1)
RISE (1)
show less...
Language
English (142)
Swedish (13)
Research subject (UKÄ/SCB)
Engineering and Technology (113)
Natural sciences (17)
Medical and Health Sciences (8)
Social Sciences (3)
Humanities (1)

Year

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Close

Copy and save the link in order to return to this view