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The automation capabilities and virtual tools within engineering disciplines, such as structural mechanics and aerodynamics, enable efficient Multidisciplinary Design Optimization (MDO) approaches to evaluate and optimize the performance of a large number of design variants during early design stages of aircraft components. However, for components that are designed to be welded, in which multiple functional requirements are satisfied by one single welded structure, the automation and simulation capabilities to evaluate welding-producibility and predict welding quality (geometrical deformation, weld bead geometrical quality, cracks, pores, etc) are limited. Besides the complexity of simulating all phenomena within the welding process, one of the main problems in welded integrated components is the existing coupling between welding quality metrics and product geometry. Welding quality can vary for every new product geometrical variant. Thus, there is a need of analyzing rapidly and virtually the interaction and sensitivity coefficients between design parameters and welding quality to predict welding producibility. This paper presents as a result an automated and interactive welding-producibility evaluation approach. This approach incorporates a data-based of welding-producibility criteria, as well as welding simulation and metamodel methods, which enable an interactive and automated evaluation of welding quality of a large number of product variants. The approach has been tested in an industrial use-case involving a multidisciplinary design process of aircraft components. The results from analyzing the welding-producibility of a set of design variants have been plotted together with the analysis results from other engineering disciplines resulting in an interactive tool built with parallel coordinate graphs. The approach proposed allows the generation and reuse of welding producibility information to perform analyses within a big spectrum of the design space in a rapid and interactive fashion, thus supporting designers on dealing with changes and taking fact-based decisions during the multidisciplinary design process.

It is expected that aero engine businesses will develop radically new types of propulsion solutions to meet the new sustainability-driven targets. Consequently, to meet new conditions not previously encountered, both in design and in production, the structural components of the engines will also have to be radically different. Implications of this are significant for aero engine manufacturers. Production will need to respond accurately and flexibly to provide advanced engine structures to new engine designs. This makes the ability to trade and optimise the balance between functional performance and cost of realising them, critical. Furthermore, the time and accuracy of such investigations is a competitive factor. In this paper, a method is proposed and demonstrated for how weld manufacturability of structural aero engine components can be simulated and traded against performance already in the early phases of design., The project leading to this paper has received funding from the Clean Sky 2 Joint Undertaking under the European Union's Horizon 2020 research and innovation programme. Grant agreement No 887174. And from the Swedish Innovation Agency (VINNOVA) through the DIFAM project (ID 2019-02756).

Summary Various authors have emphasized music’s value as beneficial intervention, with few or hardly any side effects. Further studies are called for on how music-based environmental treatment in nursing homes works in practice. The aims of the study are first to explore the subjective experiences, opinions and attitudes of health personnel from nursing homes participating in the ‘music-based environmental therapy programme (MB programme); and second, to examine why and how this programme impacts on patients and staff, and how it works in practice. It is the first qualitative study to evaluate the impact of the programme on health personnel’s daily practice in nursing homes. The sample was strategically selected by means of convenience sampling, and consisted of 26 (n = 26) nurses, managers, physiotherapists, social workers and carers from 11 nursing homes in the south-east of Norway. Data were collected in autumn 2019 using a methodological triangulation of in-depth interviews, focus groups and passive observation, and the data were analyzed using systematic text condensation. With systematic use of music in daily activities in the nursing homes, users became calmer and less outspoken, and the use of psychotropic drugs was greatly reduced. The MB programme seems to be a successful intervention that provides a unique opportunity to improve patients’ health and well-being with minimal adverse effects. This new focus on non-pharmacological approaches makes investigation of alternatives to medication vital.

Often, coping with changing requirements results in substantial overdesign, because of the ways in which design margins are allocated at the beginning of the design process. In this paper, we present a design optimization method for minimizing overdesign using additive manufacturing. We use recently defined constituents of design margins (buffer and excess) as metrics in a design optimization problem to minimize overdesign. The method can be used to obtain optimal design decisions for changing requirements. We demonstrate our method by means of a turbine rear structure design problem where changes in the temperature loads are met by depositing different types of stiffeners on the outer casing. The optimal decisions obtained by optimization minimize overdesign but ensure that requirements are met throughout the product’s lifecycle.

Requirement changes can result in substantial overdesign because of the way design margins are allocated at the beginning of the design process. We present a design optimization method for minimizing overdesign by making use of additive remanufacturing and recently defined constituents of design margins (buffer and excess). The method can be used to obtain a set of design decisions for different changing requirement scenarios. We demonstrate our method by means of a turbine rear structure design problem where changes in the temperature loads are met by depositing different types of stiffeners on the outer casing. The results of the case study are visualized in a tradespace, which allows for comparison between sets of optimal, flexible, and robust designs. Results show that the optimized set of design decisions balances flexibility and robustness in a cost-effective manner.

Technology has potential for improving the lives of persons with severe disabilities. But it's a challenge to create technology that improves lives from a person's own perspective. Co-design methods have therefore been used in the design of Assistive Technology, to include users in the design process. But it's a challenge to ensure the quality of participation with persons with significantly different prerequisites for communication than ourselves. It's hard to know if what we design is good for them in the way they themselves define it, in a communication situation, which has to be significantly different than traditional co-design. In this paper, we present a new approach to co-design with persons with severe disabilities. We call this process "trans-create", based on the creative translation we use when translating between cultures. We found that by using familiar artifacts that could be added and removed in the co-design process, we had a language for communication. By adding a personalisable digital layer to the artifacts, we could adapt, scale and redesign both tangible, visual and sound qualities in the situation dynamically. For example, by making it possible for the user to choose and activate a pink music cover card (RFID) that turns the lighting of the entire room pink and changes the music. This implies changing the distinction between designer and user, between the design process and the use process, and the view of what we create during a co-design process. That is why we have chosen to call this process "trans-create", instead of co-create, what we create for "living works", instead of design, a hybridisation between design and use, process and result.

Technology has potential for improving the lives of persons with severe disabilities. But it’s a challenge to create technology that improves lives from a person’s own perspective. Co-design methods have therefore been used in the design of Assistive Technology, to include users in the design process. But it’s a challenge to ensure the quality of participation with persons with significantly different prerequisites for communication than ourselves. It’s hard to know if what we design is good for them in the way they themselves define it, in a communication situation, which has to be significantly different than traditional co-design. In this paper, we present a new approach to co-design with persons with severe disabilities. We call this process “trans-create”, based on the creative translation we use when translating between cultures. We found that by using familiar artifacts that could be added and removed in the co-design process, we had a language for communication. By adding a personalisable digital layer to the artifacts, we could adapt, scale and redesign both tangible, visual and sound qualities in the situation dynamically. For example, by making it possible for the user to choose and activate a pink music cover card (RFID) that turns the lighting of the entire room pink and changes the music. This implies changing the distinction between designer and user, between the design process and the use process, and the view of what we create during a co-design process. That is why we have chosen to call this process “trans-create”, instead of co-create, what we create for “living works”, instead of design, a hybridisation between design and use, process and result.

Aeroengine manufacturers need to better include assessment of risk and cost for realising the novel products needed to meet the ambitions sustainability driven targets for air transport. Radical technologies are needed that simultaneously require critical manufacturing processes to be assessed already in conceptual design.In this paper, a multi-domain framework for conceptual design and evaluation is proposed that provide the ability to interactively explore the concepts that simultaneously allow a wider range of architectures can be assessed and still include weldability of the concepts.It has been demonstrated how high level, and function driven conceptual design alternatives can be modelled and evaluated to analyse risk and resilience of architectures. Geometrical concepts generated for the most interesting regimes using design of experiments covering a desired design space. For each CAD-model the welding process can be simulated to assess feasibility and lead time for welding, and return quantified results to be included in an integrated results data set for interactive decision making. The paper is the first report from a research project that improve concurrent design of product and production concepts.

Paper-based abrasive products are multilayer structures in which the first layer on the paper substrate is usually a latex barrier coating to prevent the migration of adhesive glue into the substrate. The high coat weight (10 g/m2) of latex barrier layers is a cause of environmental concerns. Hence, alternative materials that can provide the barrier function at lower coat weights are desired. In this work, microfibrillated cellulose (MFC) combined with poly(vinyl) alcohol (PVA) were explored as suitable alternatives to the current latex coatings. Barrier coating formulations containing PVA, MFC, and silica (SiO2) were developed and applied to a paper substrate using a rod coating method on a pilot scale. Coating quality and barrier performance were characterized using scanning electron microscope images, air permeance, surface roughness, water contact angle, KIT test, and oil Cobb measurements. The barrier coatings were also studied for adhesion to the subsequent coating layer. An optimal barrier function was achieved with the developed coatings at a low coat weight of ca. 3 g/m2. The adhesion of pure PVA and PVA-MFC barrier coatings to the subsequent coating layer was inadequate, however, silica addition was found to improve the adhesion.

Engineering design problems often have open-ended requirements, especially in the early stages of development. Set-based design is a paradigm for exploring, and keeping under consideration, several alternatives so that commitment to a single design can be delayed until requirements are settled. In addition, requirements may change over the lifetime of a component or a system. Novel manufacturing technologies enable designs to be remanufactured to meet changed requirements. By considering this capability during the set-based design optimization process, solutions can be scaled to meet evolving requirements and customer specifications even after commitment. Such an ability can also support a circular economy paradigm based on the return of used or discarded components and systems to working condition. We propose a set-based design methodology to obtain scalable optimal solutions that can satisfy changing requirements through remanufacturing. We first use design optimization and surrogate modeling to obtain parametric optimal designs. This set of parametric optimal designs is then reduced to scalable optimal designs by observing a set of transition rules for the manufacturing process used (additive or subtractive). The methodology is demonstrated by means of a structural aeroengine component that is remanufactured by direct energy deposition of a stiffener to meet higher loading requirements.

Designing aircraft engines is a complex process in which requirements from multiple disciplines need to be considered. Decisions about product geometry and tolerances to achieve optimized aerodynamics, product life and weight can affect the manufacturing process. Therefore, providing information to designers about process capabilities is necessary to support design exploration and analysis. In this paper, the authors propose the Welding Capability Assessment Method (WCAM) as a tool to support the systematic identification and assessment of design issues related to product geometry critical to the welding process. Within this method, a list of potential failure modes during welding is connected to specific design parameters. Once the critical design parameters have been identified, quantitative methods are proposed to calculate tolerances to reduce the likelihood of welding failures. The application of this method is demonstrated through an industrial case study where a combination of interviews and welding simulations is used to study the welding capability of a number of product geometries. This method represents an advancement from traditional qualitative guidelines and expert judgments about welding difficulties towards a more quantitative approach, supporting virtual design.

The design of aircraft engines involves computationally expensive engineering simulations. One way to solve this problem is the use of response surface models to approximate the high-fidelity time-consuming simulations while reducing computational time. For a robust design, sensitivity analysis based on these models allows for the efficient study of uncertain variables’ effect on system performance. The aim of this study is to support sensitivity analysis for a robust design in aerospace engineering. For this, an approach is presented in which random forests (RF) and multivariate adaptive regression splines (MARS) are explored to handle linear and non-linear response types for response surface modelling. Quantitative experiments are conducted to evaluate the predictive performance of these methods with Turbine Rear Structure (a component of aircraft) case study datasets for response surface modelling. Furthermore, to test these models’ applicability to perform sensitivity analysis, experiments are conducted using mathematical test problems (linear and non-linear functions) and their results are presented. From the experimental investigations, it appears that RF fits better on non-linear functions compared with MARS, whereas MARS fits well on linear functions.

Insect pollinators are declining, which often is related to intensified agriculture. Less focus has been on the effect of forestry. In many boreal forests, clear-cutting has replaced fire as the main disturbance agent, which has been negative for many species. Therefore, prescribed burning is performed, often on clear-cuts. Knowledge on the effect of fire on pollinators is, however, scarce. We sampled pollinators and their resources in 22 burned and 15 unburned clear-cuts in and around a large wildfire area in Sweden, three years after fire. We compared potential pollinator resources as well as richness, abundance and community composition of four groups of pollinators: bees (totaling 583 individuals), wasps (1226), hoverflies (416), and butterflies (7 2 8) between burned and unburned clear-cuts. Moreover, we analyzed the effect of burn severity (depth of remaining humus). We show that the diversity and cover of potential nectar/pollen plants were clearly lower in burned clear-cuts, while potential nesting resources were higher. Butterfly richness was 67% lower and abundance 89% lower in burned clear-cuts. Differences in richness and abundance were smaller for bees, wasps, and hoverflies, but their species composition differed. We found no effect of burn severity on pollinators or their resources. We conclude that burned clear-cuts have fewer pollinators three years after fire, which is driven by a loss of butterflies. However, changes in species composition from clear-cut fires could complement the fauna of unburned sites when mixed at landscape level. Future studies should follow vegetation and pollinator communities over longer time periods following clear-cut burning.

This paper presents a prescriptive approach toward the integration of value and sustainability models in an automated decision support environment enabled by machine learning (ML). The approach allows the concurrent multidimensional analysis of design cases complementing mechanical simulation results with value and sustainability assessment. ML allows to deal with both qualitative and quantitative data and to create surrogate models for quicker design space exploration. The approach has been developed and preliminary implemented in collaboration with a major aerospace sub-system manufacturer.

Effects of neighboring plants on herbivore damage to a focal plant (associational effects) have been documented in many systems and can lead to either increased or decreased herbivore attack. Mechanistic models that explain the observed variety of herbivore responses to local plant community composition have, however, been lacking. We present a model of herbivore responses to patches that consist of two plant types, where herbivore densities on a focal plant are determined by a combination of patch-finding, within-patch redistribution, and patch-leaving. Our analyses show that the effect of plant neighborhood on herbivores depends both on how plant and herbivore traits combine to affect herbivore movement and on how experimental designs reveal the effects of plant density and plant relative frequency. Associational susceptibility should be the dominant pattern when herbivores have biased landing rates within patches. Other behavioral decision rules lead to mixed responses, but a common pattern is that in mixed patches, one plant type experiences associational resistance while the other plant experiences associational susceptibility. In some cases, the associational effect may shift sign along a gradient of plant frequency, suggesting that future empirical studies should include more than two plant frequencies to detect nonlinearities. Finally, we find that associational susceptibility should be commonly observed in experiments using replacement designs, whereas associational resistance will be the dominant pattern when using additive designs. Consequently, outcomes from one experimental design cannot be directly compared to studies with other designs. Our model can also be translated to other systems with foragers searching for multiple resource types.

Habitat area is an important predictor of spatial variation in animal densities. However, the area often correlates with the quantity of resources within habitats, complicating our understanding of the factors shaping animal distributions. We addressed this problem by investigating densities of insect herbivores in habitat patches with a constant area but varying numbers of plants. Using a mathematical model, predictions of scale-dependent immigration and emigration rates for insects into patches with different densities of host plants were derived. Moreover, a field experiment was conducted where the scaling properties of odour-mediated attraction in relation to the number of odour sources were estimated, in order to derive a prediction of immigration rates of olfactory searchers. The theoretical model predicted that we should expect immigration rates of contact and visual searchers to be determined by patch area, with a steep scaling coefficient, mu = -1. The field experiment suggested that olfactory searchers should show a less steep scaling coefficient, with mu a parts per thousand -0.5. A parameter estimation and analysis of published data revealed a correspondence between observations and predictions, and density-variation among groups could largely be explained by search behaviour. Aphids showed scaling coefficients corresponding to the prediction for contact/visual searchers, whereas moths, flies and beetles corresponded to the prediction for olfactory searchers. As density responses varied considerably among groups, and variation could be explained by a certain trait, we conclude that a general theory of insect responses to habitat heterogeneity should be based on shared traits, rather than a general prediction for all species.

Computer simulations play an important role for evaluating designs in an early stages leading to that more informed decisions can be taken and thereby reducing the risk of costly re-design. In this paper, a platform currently in operation at an aeronautical company for doing extensive automated multi-objective design parameter studies on conceptual designs of aircraft engine components is studied. In the paper, an extension of the capability of the platform into making a rule-based evaluation of the welding manufacturability of the conceptual designs is proposed. The extension is tested by a prototype system at the air-craft manufacturer showing the relation between the design parameters and the manufacturability of the components. The results are presented as a manufacturability index showing what trade-offs with other performance criteria of the engine that can be made. It is shown that the manufacturability evaluation can be integrated in the knowledge value stream and supports a set-based concurrent engineering approach in the company.

För att hålla ett behagligt inomhusklimat på fartyg krävs kylning under den varma tiden på året. Denna kylning kräver energi. Detta arbete är en undersökning om huruvida denna energiåtgång kan minskas genom så kallad frikylning. ROPAX-färjan Finntrader som trafikerar linjen Malmö–Travemünde har använts som exempel. Undersökningen utfördes genom att skapa en beräkningsmodell där ett köldbärarsystem med möjlighet till frikylning kopplades in i Finntraders nuvarande HVAC-system, tillsammans med nuvarande kylmaskiner. Statistik över lufttemperatur, luftfuktighet och sjövattentemperatur för perioden 2013–2015 införskaffades. Denna statistik fördes in i beräkningsmodellen. Resultatet av beräkningarna blev att en viss mängd energi kunde sparas med frikylning, hur mycket beroende på värmeväxlarnas effektivitet. Mängden energi som kunde sparas var förhållandevis liten jämfört med kostnaden för de komponenter modellen krävde. To maintain a comfortable climate on board ships, cooling is necessary during the warm period of the year which requires energy. This thesis is a survey about whether so-called free cooling could reduce this energy consumption. The ROPAX-ferry Finntrader trafficking the route Malmö–Travemünde has been used as an example. This survey was carried out by creating a calculation model in which a brine system with a possibility of free cooling was connected to Finntrader’s current HVAC-system, alongside the current chillers. Statistics of air temperature, air humidity and sea water temperature was acquired for the period 2013-2015 and were inserted into the calculation model. These calculations showed that a certain amount ofenergy could be saved with free cooling, how much depending on the effectiveness of the heat exchangers. The amount of energy that could be saved was quite small compared to the cost of the components required by the model.

One important part of the manufacturing process of aerospace components is making inspections using Fluorescent Penetrant Inspection (FPI). This mandatory inspection represents a non-negligible part of the manufacturing and service cost. It is therefore important to make the geometry of the components suitable for inspection i.e. practicing Design for Inspection (DFI). This has been studied at an aerospace company with the aim of bringing DFI to the early stages of product development process. In this paper, a tool is proposed for the evaluation of inspectability in the early design stages. The tool is applied on CAD-models of the components automatically ranking the inspectability of design proposals using a novel inspectability index. Thus, inspectability can be considered together with other performance and manufacturing aspects forming a powerful decision support. The tool has been run and evaluated together with manufacturing staff at the aerospace company with promising results.

Roads may act as barriers to animal movements, but direct barrier effects on insects have rarely been studied. In this study we collected data on bees and wasps along two sides of a large road in Sweden using yellow pan traps. We then analyzed if the species composition differed between the two sides of the road; first for the whole community, and then only for the smallest species (which typically are poorer dispersers). As a complement, we analyzed if different vegetation variables differed between the two sides of the road, as this may also affect differences in species composition. Finally, we analyzed if species richness and abundance in general differed between the two sides and how these two response variables were explained by the vegetation variables. There was a significant difference in species composition between the eastern and the western side of the road when analyzing the whole community, and this relationship became even stronger when the largest species were excluded. The vegetation variables did not strongly differ between the two sides, and there was no difference in species richness and abundance of bees and wasps either. Abundance was, however, explained by the number of flowering plants in the surroundings of the trap. Even though using a rather limited data set, our results indicate that large roads may act as barriers on the movement of bees and wasps, especially for small species with poor dispersal ability. On the other hand, road verges may be important habitat for many species, which leads to a potential conflict that is important to consider in the planning of green infrastructure.

Everyone has a right to take part in cultural events and activities, such as music performances and music making. Enforcing that right, within Universal Design, is often limited to a focus on physical access to public areas, hearing aids etc., or groups of persons with special needs performing in traditional ways. The latter might be people with disabilities, being musicians playing traditional instruments, or actors playing theatre. In this paper we focus on the innovative potential of including people with special needs, when creating new cultural activities. In our project RHYME our goal was to create health promoting activities for children with severe disabilities, by developing new musical and multimedia technologies. Because of the users' extreme demands and rich contribution, we ended up creating both a new genre of musical instruments and a new art form. We call this new art form Embodied and Distributed Parallel DJing, and the new genre of instruments for Empowering Multi-Sensorial Things.

When searching for resources in heterogeneous environments, animals must rely on their abilities to detect the resources via their sensory systems. However, variation in the strength of the sensory cue may be mediated by the physical size of the resource patch. Patch detection of insects are often predicted by the scaling of sensory cues to patch size, where visual cues has been proposed to scale proportional to the diameter of the patch. The scaling properties of olfactory cues are, however, virtually unknown. Here, we investigated scaling rules for olfactory information in a gradient of numbers of odour sources, relevant to odour-mediated attraction under field conditions. We recorded moth antennal responses to sex pheromones downwind from pheromone patches and estimated the slope in the scaling relationship between the effective length of the odour plumes and the number of odour sources. These measurements showed that the effective plume length increased proportional to the square root of the number of odour sources. The scaling relationship, as estimated in the field experiment, was then evaluated against field data of the slope in the relationship between trap catch and release rate of chemical attractants for a wide range of insects. This meta-analysis revealed an average slope largely consistent with the estimated scaling relationship between the effective plume length and the number of odour sources. This study is the first to estimate the scaling properties of olfactory cues empirically and has implications for understanding and predicting the spatial distributions of insects searching by means of olfactory cues in heterogeneous environments.

1. The relative effect of migration and local growth on the spatio-temporal density-distribution of two co-existing herbivorous weevils, Cionus scrophulariae L. and C. tuberculosus Scop., in 32 hos ...

In product development, one critical source of knowledge is experience made in the manufacturing phase of a products lifecycle. Hence, the collaborative interaction between design and manufacturing is explored. Results from a descriptive case study of practices for reuse of manufacturing knowledge are compared with data from a previous study. Together they provide a comparison between three different business areas (automotive, aerospace and defense). The studies reveal similar problems in utilizing the full potential of knowledge reuse. This paper contributes to the research area by describing current practices within knowledge reuse. Furthermore, proposals for improved practices of knowledge reuse are identified.

This study examined the interactive effects of early and late season herbivory on the growth and reproductive output of figwort (Scrophularia nodosa). The early season herbivore is a pentatomid bug that feeds on and kills the apical meristem, while the late season herbivores are 2 weevil species and a sawfly that all feed on leaves and flowers. The direct effect of early season meristem damage on plant reproduction was quite limited, although meristem damage did cause increased branching. This change in plant morphology may entail that early season herbivores have profound indirect effects on plant reproduction by affecting the abundance of and damage caused by late season herbivores. Comparisons of plants with and without early season meristem damage, natural and artificial, also suggest that plants with meristem damage are significantly shorter throughout most of the summer and receive less damage late in season. However, the reduced damage translated to increased flowering but not to increased fruit production, suggesting that the plants were able to compensate for late season damage. In the end, and despite damage, figwort was well able to tolerate the observed meristem and leaf damage.