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Aim To assess the merit of clinical assessment tools in a neurocognitive screening following out-of-hospital cardiac arrest (OHCA). Methods The neurocognitive screening that was evaluated included the performance-based Montreal Cognitive Assessment (MoCA) and Symbol Digit Modalities Test (SDMT), the patient-reported Two Simple Questions (TSQ) and the observer-reported Informant Questionnaire on Cognitive Decline in the Elderly-Cardiac Arrest (IQCODE-CA). These instruments were administered at 6-months in the Targeted Hypothermia versus Targeted Normothermia after Out-of-Hospital Cardiac Arrest (TTM2) trial. We used a comprehensive neuropsychological test battery from a TTM2 trial sub-study as a gold standard to evaluate the sensitivity and specificity of the neurocognitive screening. Results In our cohort of 108 OHCA survivors (median age = 62, 88% male), the most favourable cut-off scores were: MoCA < 26; SDMT z ≤ -1; IQCODE-CA ≥ 3.04. The MoCA (sensitivity 0.64, specificity 0.85) and SDMT (sensitivity 0.59, specificity 0.83) had a higher classification accuracy than the TSQ (sensitivity 0.28, specificity 0.74) and IQCODE-CA (sensitivity 0.42, specificity 0.60). When using the cut-points for MoCA or SDMT in combination to identify neurocognitive impairment, sensitivity improved (0.81, specificity 0.74), area under the curve = 0.77, 95% CI [0.69, 0.85]. The most common unidentified impairments were within the episodic memory and executive functions domains, with fewer false negative cases on the MoCA or SDMT combined. Conclusion The MoCA and SDMT have acceptable diagnostic accuracy for screening for neurocognitive impairment in an OHCA population, and when used in combination the sensitivity improves. Patient and observer-reports correspond poorly with neurocognitive performance.

Aims: To describe the level of physical activity 6 months after an out-of-hospital cardiac arrest (OHCA) and to explore potential risk factors of a low level of physical activity. Methods: Post-hoc analyses of the international multicentre Targeted Hypothermia versus Targeted Normothermia after Out-of-Hospital Cardiac arrest (TTM2) trial. At 6 months, survivors at 61 sites in Europe, Australia and New Zeeland were invited to a follow-up. The participants answered two questions on self-reported physical activity. Answers were categorized as a low, moderate, or high level of physical activity and further dichotomized into a low versus moderate/high level of physical activity. Potential risk factors for a low level of physical activity were collected and investigated by univariable and multivariable logistic regression. Results: At 6 months, 807 of 939 (86%) OHCA survivors answered the two questions of physical activity; 34% reported a low, 44% moderate and 22% high level of physical activity. Obesity (OR = 1.75, 95% CI 1.10-2.77, p = 0.018), mobility problems by EuroQol 5 dimensions 5 levels (OR = 1.73, 95% CI 1.06-2.84, p = 0.029), and cognitive impairment by Symbol Digit Modalities Test (OR = 1.78, 95% CI 1.13-2.82, p = 0.013) were significantly associated with a low level of physical activity in the multivariable analysis. Conclusion: One third of the OHCA survivors reported a low level of physical activity. Obesity, mobility problems, and cognitive impairment were associated with a low level of physical activity.

Concrete dams in cold regions are designed to resist static loads from the ice sheet forming on the reservoir. Current guidelines suggest design ice loads of 50-250 kN/m based solely on geographical location, overlooking site-specific conditions. For many dams, this constitutes a considerable part of the total horizontal load and could theoretically cause problems with stability, especially for lower dams. However, the knowledge about the actual magnitude of ice loads remains limited, and no stability failure initiated by ice loads has been reported. This paper presents results from ice load measurements using a 1 X 3 m2 load panel installed at two dams in Sweden. The results from ice load measurements are presented alongside external factors such as water level, ambient temperatures, precipitation, and ice thickness, offering a more comprehensive understanding of the variables affecting ice loads on concrete dams., QC 20241211, Forecasting of ice-loads on concrete dams

IMPORTANCE: The Targeted Hypothermia vs Targeted Normothermia After Out-of-Hospital Cardiac Arrest (TTM2) trial reported no difference in mortality or poor functional outcome at 6 months after out-of-hospital cardiac arrest (OHCA). This predefined exploratory analysis provides more detailed estimation of brain dysfunction for the comparison of the 2 intervention regimens. OBJECTIVES: To investigate the effects of targeted hypothermia vs targeted normothermia on functional outcome with focus on societal participation and cognitive function in survivors 6 months after OHCA. DESIGN, SETTING, AND PARTICIPANTS: This study is a predefined analysis of an international multicenter, randomized clinical trial that took place from November 2017 to January 2020 and included participants at 61 hospitals in 14 countries. A structured follow-up for survivors performed at 6 months was by masked outcome assessors. The last follow-up took place in October 2020. Participants included 1861 adult (older than 18 years) patients with OHCA who were comatose at hospital admission. At 6 months, 939 of 1861 were alive and invited to a follow-up, of which 103 of 939 declined or were missing. INTERVENTIONS: Randomization 1:1 to temperature control with targeted hypothermia at 33 °C or targeted normothermia and early treatment of fever (37.8 °C or higher). MAIN OUTCOMES AND MEASURES: Functional outcome focusing on societal participation assessed by the Glasgow Outcome Scale Extended ([GOSE] 1 to 8) and cognitive function assessed by the Montreal Cognitive Assessment ([MoCA] 0 to 30) and the Symbol Digit Modalities Test ([SDMT] z scores). Higher scores represent better outcomes. RESULTS: At 6 months, 836 of 939 survivors with a mean age of 60 (SD, 13) (range, 18 to 88) years (700 of 836 male [84%]) participated in the follow-up. There were no differences between the 2 intervention groups in functional outcome focusing on societal participation (GOSE score, odds ratio, 0.91; 95% CI, 0.71-1.17; P =

BACKGROUND: Low level of physical activity is a risk factor for new cardiac events in out-of-hospital cardiac arrest (OHCA) survivors. Physical activity can be assessed by self-reporting or objectively by accelerometery. AIM: To investigate the agreement between self-reported and objectively assessed physical activity among OHCA survivors HYPOTHESIS: Self-reported levels of physical activity will show moderate agreement with objectively assessed levels of physical activity. METHOD: Cross-sectional study including OHCA survivors in Sweden, Denmark, and the United Kingdom. Two questions about moderate and vigorous intensity physical activity during the last week were used as self-reports. Moderate and vigorous intensity physical activity were objectively assessed with accelerometers (ActiGraph GT3X-BT) worn upon the right hip for 7 consecutive days. RESULTS: Forty-nine of 106 OHCA survivors answered the two questions for self-reporting and had 7 valid days of accelerometer assessment. More physically active days were registered by self-report compared with accelerometery for both moderate intensity (median 5 [3:7] vs. 3 [0:5] days; p < 0.001) and vigorous intensity (1 [0:3] vs. 0 [0:0] days; p < 0.001). Correlations between self-reported and accelerometer assessed physical activity were sufficient (moderate intensity: rs = 0.336, p = 0.018; vigorous intensity: rs = 0.375, p = 0.008), and agreements were fair and none to slight (moderate intensity: k = 0.269, p = 0.001; vigorous intensity: k = 0.148, p = 0.015). The categorization of self-reported versus objectively assessed physical activity showed that 26% versus 65% had a low level of physical activity. CONCLUSION: OHCA survivors reported more physically active days compared with the results of the accelerometer assessment and correlated sufficiently and agreed fairly and none to slightly.

Dammhaverier är mycket ovanliga och därför är kunskapen om brottförloppet vid ett potentiellt dammbrott begränsad. Uppstår brottet utan förvarning, eller finns tidiga tecken på allvarliga problem? Hur utvecklas brottsbräschen under brottförloppet? Detta är frågor som blivit än mer aktuella efter tre internationella dammhaverier under 2023. För att söka svar har en serie skalmodellförsök utförts där haverier av betongdammar simuleras. En viktig parameter vid säkerhetsbedömningen av en betongdamm består i att utvärdera dess stabilitet. Förenklat görs dettag enom att jämföra om dammkroppens vikt är tillräcklig för att stå emot lasten från vattnets tryck. Traditionellt beaktas enbart en mindre del av en betongdamm när dess stabilitet utvärderas men de nya försöken indikerar att det vore eftersträvansvärt att undersöka hela dammen samtidigt eftersom lasten fördelas mellan konstruktionsdelarna. Många betongdammars tillstånd övervakas idag genom automatiska mätningarav till exempel vattenstånd, förskjutningar och grundvattentryck. Dock finns det ingen standardiserad metod för att definiera larmgränser,vilket detta projekt syftar till att utveckla i framtiden., QC 20240118

QC 20240115

Research on embankment dam monitoring was recently carried out at a test site in Sweden, with the objectives of: testing geophysical meth-ods of locating defects in the structure; and, using geotechnical instruments to check the behaviour of the dam during first impounding, and subsequently during fluctuations of the reservoir level. The main purpose was to investigate if conventional geophysical methods can be used to detect embedded faults at a rockfill embankment dam in a blind test. Initially, a number of scientists with different specializations in geophysical methods were invited to perform a synthetic pre-simulation assessement to determine if their non-destructive methods would reveal the defects. The test facility is described, the embankment dam constructed for the study and some highlights of the results., QC 20231212

Large volumes of steel fibre reinforced shotcrete (sprayed concrete) and steel bolts are commonly used to support tunnels in hard rock. This generates a high CO2-footprint which must be reduced in order to decelerate the continuously increasing average temperature worldwide caused by the emissions of greenhouse gases. Thus, alternative design methods and the possibility to use other materials than steel are currently investigated. Work is ongoing on testing the load-bearing capacity of shotcrete reinforced with fibres of steel, basalt and synthetic materials. This also includes a comparison between tests using Round Determinate Panels (RDP) and four-point bending of beams. Moreover, the practical use of RDP testing as a quality control methodology is also investigated in situ. Here, the goal is to identify several shotcrete mixes suitable for use in tunnelling so that the right material and fibre volume can be used in the right place., QC 20231023

Although the failure of a concrete dam is a complex and highly dynamic process, the current safety assessments of concrete gravity and buttress dams rely on a simplified 2D stability analysis, which neglects the load redistribution due to 3D monolith interactions and the valley shape. In addition, the estimation of breach parameters in concrete dams is based on assumptions rather than analyses, and better prediction methods are needed. Model tests have been conducted to increase the understanding of the failure behavior of concrete dams. A scale model buttress dam, with a scale of 1:15, consisting of 5 monoliths that were 1.2 m in height and 4 m in width, was constructed and loaded to failure using water pressure. The model dam had detachable abutment supports and shear keys to permit variations in the 3D behavior. The results showed that the shear transfer was large between the monoliths and that the failure of a single dam monolith is unlikely. A greater lateral restraint gives not only a higher failure load but also a better indication of impending failure. These findings suggest that the entire dam, including its boundary conditions, should be considered during a stability assessment. The results also suggest that the common assumption in dam safety codes that a single monolith fails during flooding analysis is not conservative. The dataset obtained provides a foundation for the future development of dam-monitoring alarm limits and for predictive models of dam-breaching processes., QC 20231017

Dam failures may have catastrophic consequences, including the release of largeamounts of water, significant property damage, and loss of life. However, safety assessments ofconcrete gravity and buttress dams often rely on simplified methods that do not consider the interactionbetween monoliths, the shape of the foundation or the presence of stiff abutments. Numericalmodeling can be a valuable tool for analyzing the stability of these dams, but it can bedifficult to validate these models due to a lack of documented dam failures. This paper presentsthe results of a numerical study examining the ability of dynamic finite element analyses to simulatedam failures. The study used the results from a series of physical model tests as a case studyfor validation. It was found that the numerical model was able to accurately reproduce the failuremode and breach development observed in the physical model tests and capture the effect of theloading rate on the failure mode and time for the failure to develop. Simulations were also performedin prototype scale to verify that the model tests were representative of a real dam failure.Further research is needed to determine the reliability of the numerical models under differentloading conditions and in realistic geological settings. However, these findings suggest that numericalmodeling can be a valuable tool for analyzing the stability of concrete gravity and buttressdams and predicting the development of failures., QC 20231017

Fibre-reinforced shotcrete (sprayed concrete) is one of the major components in the support system for tunnels in hard rock. Several empirical design methodologies have been developed over the years due to the complexity and many uncertainties involved in rock support design. Therefore, this paper aims to highlight how the choice of design methodology and fibre type impacts the structural capacity of the lining and the emission of greenhouse gases (GHG). The paper starts with a review of different design methods. Then, an experimental campaign is presented in which the structural performance of shotcrete reinforced with various dosages of fibres made of steel, synthetic and basalt was compared. A case study is presented in which the permanent rock support is designed based on the presented design methods. Here, only the structural requirements were considered, and suitable dosages of fibres were selected based on the experimental results. The emission of GHG was calculated for all design options based on environmental product declarations for each fibre type. The result in this paper indicates that synthetic fibres have the greatest potential to lower the emissions of GHG in the design phase. Moreover, the choice of design method has a significant impact on the required dosage of fibres., QC 20230307

Drönare är ett växande fenomen i dagens samhälle och deras användningsområdenhar snabbt ökat de senaste åren. För att underlätta utvecklingen av drönarteknologi kansimuleringar tillämpas då de möjliggör testning i en kontrollerad och riskfri miljö. I dettaprojekt visualiseras simuleringar av drönare i ett försök att skapa värde för denna utveckling. Visualiseringen skedde med hjälp av Unreal Engine 5. Under projektets gång studerades arbetsmetoderna som nyttjades och hur en systemanatomi kan bidra till utvecklingen iett småskaligt mjukvaruprojekt. Största värdet som producerades för kunden var kommunikationsmodulen. Kommunikationen uppnåddes med hjälp av två JSON-filer som visualiseringen respektive simuleringen skrev till för att kommunicera med varandra. Värdeti denna modul ligger i att kunden sökte en modulär lösning för att kommunicera mellanen 3D-visualisering och en simulering. En erfarenhet som uppmärksammades angåendearbetsmetoderna är vikten av en fungerande gruppdynamik. Bidragande faktorer till detvar agila arbetsmetoder, goda kommunikationsvägar och en väl planerad användning avGit. Systemanatomier upplevdes ge begränsat värde till projektet.

Embankment dams may be damaged by internal erosion, which ultimately may lead to a failure. During internal erosion, finer soil particles from the core soil are being washed out. To restore the core function, injection grouting may be undertaken. Grouting the core of an embankment dam should be performed with a grout with similar characteristics as the original core soil. This grout type is commonly used in compaction grouting, e.g., a low mobility grout. The grout is similar to a fine-grained moraine core soil, but given its stiffness, it is difficult to permeate a damaged core soil. A modified low mobility grout containing sand, limestone filler, bentonite, plasticizer, air release agent and water has been tested in the laboratory with focus on permeation. Grouting was done in different sized aggregates. Impact of paste-to-aggregate ratio, grout consistency, maximum grain size of grout, coarseness of grouted material, and grouting methodology was tested. Higher paste-to aggregate ratios and lower viscosity/yield strength in/of the grout improved the permeation. Initially pressurized grouting compared to only hydrostatic pressures followed by stepwise pressure increased grouting was furthermore identified as a factor to improve the permeation., Validerad;2024;Nivå 2;2024-03-15 (hanlid);Funder: Svenskt Vattenkraftcentrum (SVC);Full text license: CC BY

In recent decades, many cities have become densely populated due to increased urbanization, and the transportation infrastructure system has been heavily used. The downtime of important parts of the infrastructure, such as tunnels and bridges, seriously affects the transportation system’s efficiency. For this reason, a safe and reliable infrastructure network is necessary for the economic growth and functionality of cities. At the same time, the infrastructure is ageing in many countries, and continuous inspection and maintenance are necessary. Nowadays, detailed inspections of large infrastructure are almost exclusively performed by inspectors on site, which is both time-consuming and subject to human errors. However, the recent technological advancements in computer vision, artificial intelligence (AI), and robotics have opened up the possibilities of automated inspections. Today, semiautomatic systems such as drones and other mobile mapping systems are available to collect data and reconstruct 3D digital models of infrastructure. This significantly decreases the downtime of the infrastructure, but both damage detection and assessments of the structural condition are still manually performed, with a high impact on the efficiency and accuracy of the procedure. Ongoing research has shown that deep-learning methods, especially convolutional neural networks (CNNs) combined with other image processing techniques, can automatically detect cracks on concrete surfaces and measure their metrics (e.g., length and width). However, these techniques are still under investigation. Additionally, to use these data for automatically assessing the structure, a clear link between the metrics of the cracks and the structural condition must be established. This paper presents a review of the damage of tunnel concrete lining that is detectable with optical instruments. Thereafter, state-of-the-art autonomous tunnel inspection methods are presented with a focus on innovative mobile mapp, QC 20230426, TACK -Tunnel Automatic CracK Detection

Dam safety measures on the Vattenfall hydropower facility Lilla Edet, in Sweden are, ongoing by replacing parts of the old spillway dam from the 1920s to increase discharge capacity. A climate enhanced concrete without needs for any post-cooling to avoid thermal cracking has been developed for the project. A series of tests from initial laboratory tests via development of a production mix and a full-scale mock-up preceded the construction works on site. Increase of the maximum aggregate sizes from today’s commonly used 27 mm up to 45 mm was introduced to reduce the cement content. Basic tests to verify fresh properties, air void content, strength development, shrinkage etc. was done for a series of different supplementary cementitious materials before selecting fly ash from combustion of pulverized hard coal (PFA) as cement replacement. Examination of the durability aspects like freeze-thaw and carbonation resistance by accelerated test showed no or limited impact on the properties. Development and optimization of the production mix, with use of locally available materials, was done in cooperation with the concrete supplier. The mock-up tests included two large size beams, one with reference concrete and one with the developed concept concrete. Representative reinforcement (dimensions and spacing) was installed, a full-scale concrete pump used and workers from the project executed the casting. The outcome was successful without blockage during pumping, no honeycombing and happy workers. By using installed gauges and optic fibers, early age behavior in terms of temperature and strain development was measured to be able to estimate the risk for thermal cracking. The concept concrete showed to give a substantially reduced riskfor early age thermal cracks in comparison to the reference concrete. With support from the investigations, a decision to deviate from accepted levels of cement replacement in standards was taken. This was possible since the concrete concept prove, Part of ISBN 978-91-527-8078-7QC 20231204

The Lilla Edet hydropower dam, inaugurated in 1926, is located north of Gothenburg along the river Göta älv, in Sweden. It was originally designed to supply power for the main railway line between Stockholm and Gothenburg. The need for dam safety improvements, including the capability of discharging a flood with a return period of 1:10000 years, prompted the partial reconstruction of the spillway dam. This paper describes the design decisions that have been taken regarding hydrology, hydraulic design, geological conditions, and the development of a low GHG with a reduced CO2 footprint, which does not require post-cooling., QC 20230825

Hydro power facilities in Sweden are in general exposed to large temperature variations betweensummer and winter, high moisture levels and high hydrostatic pressure on water retaining structures.In concrete structures with insufficient properties these factors co-operate and can result indegradation by e.g., frost action, erosion, leaching and stresses that can aggravate leakage of waterand further degradation or cracking of the concrete material. In concrete dams and hydro power plants different kind of joints are installed. Cold joints anddilatation joints are two common types. Dilatation joints must be designed and constructed sothey are both water retaining and flexible enough to follow thermal movements of the concretewithout rupturing. A joint that is not well constructed with a good performance can jeopardize thedam safety for a hydro power facility with uncontrolled leakage, ice-formation, degradation orproblematic erosion on the down-stream side. A laboratory study of concrete from an dilatation joint has been performed in this project. Thestudied materials are taken from a larger concrete slab of a spillway sill of a concrete dam. Thescope of the project has been to study the characteristics of the concrete around the water stop anddilatation joint. The goal was to learn more about the mechanisms behind the degradation andleaking of expansion joints., Part of ISBN 978-91-527-8078-7QC 20231208

The core of dam safety is to safely store and discharge water and thereby prevent uncontrolled release of water. Excess water, e.g. in a flooding situation, is commonly discharged via different types of spillways (gated, weirs, surface, bottom outlets etc.). The turbine discharge is typically not included in the capacity as flooding scenarios could cause a grid blackout rendering the turbine incapable of operating. This paper describes a project that has tested island operation of a hydropower unit equipped with a developed dump-load device. The dump-load device allows the unit operating even during a black-out without risk for failure of the unit and thus assure the discharge capacity via the waterways connected to the unit. Stable operation of the dump-load verified in the tests together with high reliability opens for the turbine discharge to be included inthe total discharge capacity of a facility. A cost-benefit analysis of the suggested solution and a brief description of the past and planned development of the device is given. In addition to the extra discharge capacity, the new system can also be used to reduce the risk for surge during start and stop sequences. Implementation of the system in two different facilities, with different purpose, is planned and details on the coming installations and the technical solutions around them is given. A cost comparison between conventional spillway gates and dump-load indicates a factor of ten less for dump-load for a given increase in discharge capacity. The safety analyses shows that the turbine discharge should be included in the total discharge capacity of a facility if a dump load device is present., QC 20230825

In the way towards a carbon neutral construction industry, the partial substitution of cement clinker by alternative binders is becoming increasingly popular in the design of low-carbon concrete mixes. However, as new concrete mixes are developed, the parameters governing the risk of early-age cracking arising from restraint forces due to thermal and shrinkage deformations need to be investigated for each mix. This paper reports the results of a field test in which distributed optical fiber sensors (DOFS) were used to monitor strain and temperature in two large-scale prisms cast against the ground. One of the specimens was cast with a reference concrete mix with CEM I whereas in the other mix cement was partly replaced by fly ash. After casting, mineral wool was used to insulate the specimens in order to reproduce realistic conditions in large mass concrete elements. Temperature measurements enabled a direct comparison of the heat generated by each mix as well as the estimation of the strength development. Strain measurements, on the other hand, gave an indication of the variation of the degree of restraint along the height of the specimens. Using available models for concrete creep, the tensile stresses along the specimens were calculated at different heights and compared to the expected tensile strength in order to assess the crack risk. After removing the insulation, measured strains exhibited a strong dependence on external temperature variations. The test results proved useful to analyse the early-age behaviour of concrete., QC 20230725

ImportanceThe Targeted Hypothermia vs Targeted Normothermia After Out-of-Hospital Cardiac Arrest (TTM2) trial reported no difference in mortality or poor functional outcome at 6 months after out-of-hospital cardiac arrest (OHCA). This predefined exploratory analysis provides more detailed estimation of brain dysfunction for the comparison of the 2 intervention regimens.ObjectivesTo investigate the effects of targeted hypothermia vs targeted normothermia on functional outcome with focus on societal participation and cognitive function in survivors 6 months after OHCA.Design, Setting, and ParticipantsThis study is a predefined analysis of an international multicenter, randomized clinical trial that took place from November 2017 to January 2020 and included participants at 61 hospitals in 14 countries. A structured follow-up for survivors performed at 6 months was by masked outcome assessors. The last follow-up took place in October 2020. Participants included 1861 adult (older than 18 years) patients with OHCA who were comatose at hospital admission. At 6 months, 939 of 1861 were alive and invited to a follow-up, of which 103 of 939 declined or were missing.InterventionsRandomization 1:1 to temperature control with targeted hypothermia at 33 °C or targeted normothermia and early treatment of fever (37.8 °C or higher).Main outcomes and measuresFunctional outcome focusing on societal participation assessed by the Glasgow Outcome Scale Extended ([GOSE] 1 to 8) and cognitive function assessed by the Montreal Cognitive Assessment ([MoCA] 0 to 30) and the Symbol Digit Modalities Test ([SDMT] z scores). Higher scores represent better outcomes.ResultsAt 6 months, 836 of 939 survivors with a mean age of 60 (SD, 13) (range, 18 to 88) years (700 of 836 male [84%]) participated in the follow-up. There were no differences between the 2 intervention groups in functional outcome focusing on societal participation (GOSE score, odds ratio, 0.91; 95% CI, 0.71-1.17; P = .46) or in cogni

When dealing with customers, original equipment manufacturers (OEMs) classify vehicular usage by resorting to simplified, often colloquial, descriptions that allow for a rough understanding of the operating conditions and the user’s needs. In this way, the information retrieved from the customers is exploited to guide their choices in terms of vehicle design and configuration, based on the characteristics of the transport application, labeled using intuitive metrics. However, a common problem in this context is the absence of any formal connection to lower levels of representation that might effectively be used to assess vehicular energy performance in simulation, or for design optimization using mathematical algorithms. Indeed, both processes require more accurate modeling of the surroundings, including exhaustive information about the local road, weather, and traffic conditions. Therefore, starting with a detailed statistical description of the environment, this paper proposes a method for mathematical classification of transport missions and applications within the theoretical framework of the operating cycle (OC). The approach discussed in the paper combines a collection of statistical models structured hierarchically, called a stochastic operating cycle (sOC), with a bird’s-eye view description of the operating environment. The latter postulates the existence of different classes, which are representative of the usage and whose definition is based on simple metrics and thresholds expressed mathematically in terms of statistical measures. Algebraic expressions, called operating classes in the paper, are derived analytically for all the stochastic models presented. This establishes a connection between the two levels of representation, enabling to simulate longitudinal vehicle dynamics in virtual environments generated based on the characteristics of the intended application, using log data collected from vehicles and/or information provided

In the assessment of concrete dams in cold climate, it is common that the theoretical stability becomes insufficient for load cases that include ice loads. However, the magnitude and return period of these ice loads have a high degree of uncertainty. This study estimates the magnitude of ice loads on eight concrete dam monoliths using measurements of their displacement from 29 winters. In the displacement signals, events are identified and assumed to be caused solely by ice loads. The observed displacement during an event is interpreted as an ice load using a load-displacement relationship derived from FE simulations of each dam. These simulations show that ice loads of the magnitudes given in design guidelines and recorded in previous measurements would significantly affect the structural response of the studied dams. However, only small traces of ice loads can be found in the observed responses of the studied dams. The estimated ice loads are significantly lower than the ice loads recorded in traditional ice load measurements. These results indicate that the average magnitude of ice load on an entire monolith is significantly lower than the measured local pressures. This would imply that ice loads may be a smaller concern regarding dam safety than previously believed., QC 20220318

In this dataset, data from experimental testing of fibre-reinforced shotcrete is presented. The dataset contains five different fibres made of steel (Dramix 3D, Dramix 4D and Dramix5D), synthetic (BarChip R54) and basalt (MiniBar). Preparation of specimens and testing were performed by Vattenfall R&D in Älvkarleby, Sweden. This first version of the dataset contains the results for shotcrete specimens prepared through casting. The same shotcrete mix was used for all specimens, and three different dosages were used for each of the fibres except for Dramix 5D, for which only two dosages were tested. The dataset contains the shotcrete mix and standard output for the test of compressive strength according to EN 12390-3, residual flexural strength according to EN 14488-3 and energy absorption according to ASTM C1550. This dataset can be used to study how the structural toughness of fibre-reinforced shotcrete is affected by the dosage of fibre. Moreover, the data can be used to compare the structural performance of fibres of different materials. The data also provide a foundation to select a reasonable dosage of fibres to fulfil the structural requirements put on shotcrete in the design phase., QC 20230404

Världen står inför en enorm utmaning där utsläppen av växthusgaser måste minskas för att bromsa den ständigt ökande globala medeltemperaturen. Samtidigt har en lång urbaniseringstrend lett till att transportinfrastrukturen i många tätbefolkade städer måste byggas ut för att bibehålla ett fungerande transportnät. I många fall är tunnlar det mest fördelaktiga alternativet eftersom de inte stör den befintliga stadsbilden. För att minska klimatpåverkan från byggandet av nya tunnlar har Trafikverket initierat ett forskningsprojekt som ska undersöka potentialen för alternativa fibrer och detta drivs av avdelningen för Betongbyggnad på KTH., QC 20221227

QCR 20221025

QC 20221025

Hydropower is an essential source of renewable energy. To secure power production in cold climates, it is of vital importance to continuously collect information regarding ice build-up around the power plant. The amount of ice, and the quality of the same, can cause significant loss in power production. Ice loads on dam structures are complicated to model and predict without plenty of data points. Traditionally this is performed by foot and using drilling, which is not only a safety issue but usually delivers too few data points to obtain an accurate model of the ice load. With recent developments of airborne GPR equipment, hazardous areas can be investigated safely and efficiently. Furthermore, in comparison to traditional methods airborne GPR collects vast amounts of data points, thus helping create better and more stable models for ice-loads. This paper covers a study from around a hydropower plant in northern Sweden. The study discusses the pros and cons of using air borne GPR equipment for securing hydropower production in cold climate areas., QC 20230908

QC 20230825

Sedan 2021 pågår byggfasen i ett projekt med fokus på flödesanpassning och delförnyelse av utskovsdammen vid Vattenfalls anläggning Lilla Edet i Göta älv. Till den nya dammdelen kommer cirka 8000 m3 betong att användas under uppförandet. För att minska koldioxidavtrycket från den betong som ska användas och för att reducera risken för temperaturrelaterad sprickbildning har en klimatförbättrad betong med mindre cement utvecklats., QC 20230825

Background: The brain is susceptible to hypoxic-ischemic brain injury in conjuction with out-of-hospital cardiac arrest (OHCA). Cognitive impairments are documented in about half of all OHCA survivors, however with a pronounced heterogeneity in measurements and findings. More detailed studies and instruments that are sensitive to OHCA-related cognitive impairment, including predictive models to identify individuals at risk, are needed. It is also unclear how different neurocognitive outcome methods are related to each other, to the brain injury, and to associated factors.Aims: The overall aim of this thesis was to explore the extent of neurocognitive impairment following OHCA in the late recovery phase. Specific aims per papers included in this thesis were: I) To examine the psychometric properties of an observer-reported questionnaire modified for usage after cardiac arrest, the Informant Questionnaire on Cognitive Decline in the Elderly-Cardiac Arrest (IQCODE-CA). II) To explore associations between four neurocognitive outcome methods administered in the late recovery phase and early hypoxic-ischemic brain injury assessed by the biomarker serum neurofilament light (NFL), and to compare the agreement for the four outcome methods. III) To describe the rationale and, IV) report initial results of detailed assessment of neurocognitive impairment in OHCA survivors, compare the cognitive performance to a cohort of participants following acute myocardial infarction (MI), and investigate the relationship between cognitive performance and the associated factors of emotional problems, fatigue, insomnia, and cardiovascular risk factors.Methods: I & II) Post-hoc analyses of surviving participants of the international multicenter Target temperature management 33 °C versus 36 °C after out-of-hospital cardiac arrest trial (TTM-trial), its biobank, and its cognitive sub-study, with a follow-up at 6 months post-arrest. III & IV) Prospective inclusion of surviving participants of t