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Ventilation strategies and children\u27s perception of the indoor environment in Swedish primary school classrooms
Get PDFThis study explored the relationship between children\u27s subjective perception of indoor environmental quality in classrooms, measured thermal and air quality factors, and the type of ventilation. Environmental data were collected in 45 classrooms in 23 primary schools in Sweden during the heating season. Schools with three types of ventilation were recruited: natural or exhaust ventilation (category A), balanced supply-exhaust with constant air volume (category B), and balanced supply-exhaust with variable air volume or demand-controlled ventilation (category C). 796 children (8–14 years of age) answered a questionnaire about their perception of the classroom\u27s indoor environment. Based on ten dichotomous questions, the children\u27s overall perceptions and subjective well-being was scored (“Individual score”) from worst (0) to best (10) perception. A Perception Index (PI) was calculated as the arithmetic mean of the Individual scores from all children in a given classroom. We did not find statistically significant differences in the Individual scores or PI between the three ventilation categories. However, the PI of classrooms with ventilation category A, which also had lower ventilation rates and higher concentrations of pollutants, was noticeably lower than that in classrooms with ventilation category B or C. Correlations between the PI and most of the measured environmental parameters or the individual questions about perception were weak and not significant. The PI may be improved by including factors not considered in this study, such as those related to acoustic and lighting conditions
More-Than-Human Perspectives and Values in Human-Computer Interaction
No full textIn this special interest group (SIG) we invite researchers, practitioners, and educators to share their perspectives and experiences on the expansion of human-centred perspective to more-than-human design orientation in human-computer interaction (HCI). This design for and with more-than-human perspectives and values cover a range of fields and topics, and comes with unique design opportunities and challenges. In this SIG, we propose a forum for exchange of concrete experiences and a range of perspectives, and to facilitate reflective discussions and the identification of possible future paths
Assessing the eco-efficiency benefits of empty container repositioning strategies via dry ports
Get PDFTrade imbalances and global disturbances generate mismatches in the supply and demand of empty containers (ECs) that elevate the need for empty container repositioning (ECR). This research investigated dry ports as a potential means to minimize EC movements, and thus reduce costs and emissions. We assessed the environmental and economic effects of two ECR strategies via dry ports—street turns and extended free temporary storage—considering different scenarios of collaboration between shipping lines with different levels of container substitution. A multiparadigm simulation combined agent-based and discrete-event modelling to represent flows and estimate kilometers travelled, CO2 emissions, and costs resulting from combinations of ECR strategies and scenarios. Full ownership container substitution combined with extended free temporary storage at the dry port (FTDP) most improved ECR metrics, despite implementation challenges. Our results may be instrumental in increasing shipping lines’ collaboration while reducing environmental impacts in up to 32 % of the inland ECR emissions
Model-based prediction of progression-free survival for combination therapies in oncology
Get PDFProgression-free survival (PFS) is an important clinical metric for comparing and evaluating similar treatments for the same disease within oncology. After the completion of a clinical trial, a descriptive analysis of the patients\u27 PFS is often performed post hoc using the Kaplan–Meier estimator. However, to perform predictions, more sophisticated quantitative methods are needed. Tumor growth inhibition models are commonly used to describe and predict the dynamics of preclinical and clinical tumor size data. Moreover, frameworks also exist for describing the probability of different types of events, such as tumor metastasis or patient dropout. Combining these two types of models into a so-called joint model enables model-based prediction of PFS. In this paper, we have constructed a joint model from clinical data comparing the efficacy of FOLFOX against FOLFOX + panitumumab in patients with metastatic colorectal cancer. The nonlinear mixed effects framework was used to quantify interindividual variability (IIV). The model describes tumor size and PFS data well, and showed good predictive capabilities using truncated as well as external data. A machine-learning guided analysis was performed to reduce unexplained IIV by incorporating patient covariates. The model-based approach illustrated in this paper could be useful to help design clinical trials or to determine new promising drug candidates for combination therapy trials
Battery as a service: Analysing multiple reuse and recycling loops
Get PDFThis study investigates the effects on new product demand and raw materials from the growth of a company\u27s product-service system (PSS), using dynamic material flow analysis. The PSS involves multiple reuse and recycling of lithium-ion battery subpacks for mining equipment. While effects differ over time, 13% of new subpacks and 13–59% of primary material demand is reduced within the PSS until 2050. Supply of subpacks for reuse surpasses demand, limiting displacement of new subpacks. Reuse increases battery self-sufficiency and has limited effects on primary material demand when recycling is efficient, but more so when recycling is less efficient. Thus, if efficient recycling is unachievable, reuse becomes more important for raw material self-sufficiency in the PSS. Reusing batteries could lead to European recycled content targets not being reached in time. Thus, such targets are challenging to balance with policy goals for reuse and pose risks for companies relying on extensive reuse
A Proposed Workflow for Conceptual Visualization Studies in Urban 3D-Models
Get PDFDifferent types of invisible parameters, such as air quality and noise, are all affected by new constructions of infrastructure and buildings and should be considered as important aspects in the design of new urban environments. At the same time these parameters are difficult to communicate in a comprehensible way and their consequences can be difficult to grasp for non-experts. Effective visualization offers possibilities to include and create consensus among stakeholders in urban planning processes and thus contributes to a holistic view and more sustainable solutions. This paper presents and discusses a proposed method for conceptual explorations for visualizing environmental data, using a so-called sandbox model with fictitious data.\ua0 One question is in focus: How can a sandbox model be used for the development of visualization concepts in urban 3D-models? In this paper we demonstrate our methodology using noise pollution data applied in one of our research projects carried out together with the Swedish Transport Administration (Trafikverket). This project explores new solutions for visualization of environmental data in Trafikverket\u27s geographically large-scale 3D-models. In order to conduct design elaborations in an adapted environment a sandbox model was developed as part of the workflow. Here various concepts for visualization solutions were developed and tested in a series of user tests. Based on this developed methodology through application, we propose guidelines for conceptional elaborations in a sandbox model for visualization of data in urban 3D-models. This research approach contributes to developing new methodology for information visualization of environmental data in urban 3D-models
The Link between Serum 25-Hydroxyvitamin D, Inflammation and Glucose/ Insulin Homeostasis Is Mediated by Adiposity Factors in American Adults
Get PDFPrior studies have suggested a significant association between 25-hydroxyvitamin D (25(OH)D) concentrations with markers of inflammation and glucose and insulin homeostasis. However, it is unclear whether these associations are confounded or mediated by adiposity. We used an established mediation analysis to investigate the role of adiposity in the relation between serum 25(OH)D with markers of inflammation and glucose and insulin metabolism. We used data from National Health and Nutrition Examination Survey (2005-2010), to evaluate the associations between serum 25(OH)D and markers of insulin resistance or inflammation, and whether these associations are mediated by adiposity factors including body mass index (BMI, marker of body adiposity), waist circumference (WC, marker of central adiposity), anthropometrically predicted visceral adipose tissue (apVAT), and Visceral Adiposity Index (VAI). Analysis of co-variance and conceptual causal mediation analysis were conducted taking into consideration the survey design and sample weights. A total of 16,621 individuals were included; 8607 (48.3%) participants were men and the mean age of the population was 47.1 years. Mean 25(OH)D serum concentration for the overall population was 57.9\ub10.1 nmol/L with minimal differences between men and women (57.5\ub10.2 nmol/L and 58.2\ub10.2 nmol/L, respectively). After adjustment for age, sex, season and race/ethnicity, mean levels of C-reactive protein (CRP), apolipoprotein B (apo-B), fasting blood glucose (FBG), insulin, homeostatic model assessment of IR (HOMA-IR) and β cell function (HOMA-β), haemoglobin A1c (HbA1c), and 2-h glucose were lower for the top quartile of serum 25(OH)D (all p<0.001). Body mass index (BMI) was found to have significant mediation effects (to varied extent) on the associations between serum 25(OH)D and CRP, apo-B, fasting glucose, insulin, HOMA-IR, HOMA-B and HbA1c (all p<0.05). Both waist circumference and apVAT were also found to partly mediate the associations between serum 25(OH)D with CRP, FBG, HbA1c, triglycerides and HDL-cholesterol (all P < 0.05). VAI was found to have mediation effects on CRP only (p<0.001). Using a mediation model, our findings suggest that the relationship between serum 25(OH)D, insulin resistance and inflammation, may be in part mediated by adiposity. These findings support the importance of optimizing 25(OH)D status in conditions with abnormal adiposity (i.e., obesity) and treatments for the prevention of cardio-metabolic diseases affecting adipose tissue metabolism (i.e., weight loss)
Fluidized bed steam cracking of rapeseed oil: exploring the direct production of the molecular building blocks for the plastics industry
Get PDFFossil-based production of plastics represents a serious sustainability challenge. The use of renewable and biogenic resources as feedstocks in the plastic industry is imminent. Thermochemical conversion enables the production of the molecular building blocks of plastic materials from widely available biogenic resources. Waste cooking oil (WCO) represents a significant fraction of these resources. This work provides insights into the thermochemical conversion of the fatty acids present in WCO, where rapeseed oil is used as the source of fatty acids. The experimental results reveal that fluidized bed steam cracking of rapeseed oil in the temperature range of 650-750 degrees C yields a product distribution rich in light olefins and mono aromatics. Up to 51% of light olefins, 15% of mono aromatics, and 13% of light paraffins were recovered through steam cracking. This means that up to 70% of the carbon in rapeseed oil was converted into molecular building blocks in a single step. The main conclusion from this study is that WCO and vegetable oils represent viable biogenic feedstocks for the direct production of the molecular building blocks, where the conversion is achieved through steam cracking in fluidized beds
Deep Instance Segmentation with Automotive Radar Detection Points
No full textAutomotive radar provides reliable environmental perception in all-weather conditions with affordable cost, but it hardly supplies semantic and geometry information due to the sparsity of radar detection points. With the development of automotive radar technologies in recent years, instance segmentation becomes possible by using automotive radar. Its data contain contexts such as radar cross section and micro-Doppler effects, and sometimes can provide detection when the field of view is obscured. The outcome from instance segmentation could be potentially used as the input of trackers for tracking targets. The existing methods often utilize a clustering-based classification framework, which fits the need of real-time processing but has limited performance due to minimum information provided by sparse radar detection points. In this paper, we propose an efficient method based on clustering of estimated semantic information to achieve instance segmentation for the sparse radar detection points. In addition, we show that the performance of the proposed approach can be further enhanced by incorporating the visual multi-layer perceptron. The effectiveness of the proposed method is verified by experimental results on the popular RadarScenes dataset, achieving 89.53% mean coverage and 86.97% mean average precision with the IoU threshold of 0.5, which is superior to other approaches in the literature. More significantly, the consumed memory is around 1MB, and the inference time is less than 40ms, indicating that our proposed algorithm is storage and time efficient. These two criteria ensure the practicality of the proposed method in real-world systems
Verification of the Maximum Stresses in Enhanced Welded Details via High-Frequency Mechanical Impact in Road Bridges
Get PDFHigh-frequency mechanical impact (HFMI) is an efficient post-weld treatment technique that enhances fatigue strength in metallic welded structures. Steel or steel-concrete composite road bridges, where the fatigue limit state often governs the design, compose one category of structures that can benefit from the application of this technology. To assert an improvement in fatigue strength using HFMI, the induced compressive residual stresses must be stable. Therefore, the maximum service stresses that can be allowed on HFMI-treated joints should be controlled to avoid the relaxation of the induced beneficial compressive stresses by HFMI treatment. Using statistical analysis of recorded traffic, this paper compares the measured maximum traffic loads to those generated by a load model. More than 870,000 and 470,000 recorded vehicles from traffic measurements in Sweden and the Netherlands are used in this analysis. To capture the characteristic bending moment, the daily maxima of the resulting measured load effect are combined with the extreme value distribution of the bending moment. In addition, it is found that the characteristic load combination is the best-studied option to assess the maximum stress in HFMI-treated weldments in road bridges