| 1. |
- Amann, Daniel, et al.
(författare)
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Inducing Affordability?: Observations From An Experimental Study Of Concept Generation
- 2021
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Ingår i: Proceedings of the 22th CINet conference, September 12 – 14, Gothenburg, Sweden. - Enschede. - 9789077360248
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Konferensbidrag (refereegranskat)abstract
- Early preliminary concepts are claimed to have a profound impact on the final product. Since these concepts often are based on intuitive judgements, it is important that these judgements are appropriate for the desired outcome. Intuition is derived from what one brings to mind, and consequently, the access to information is important for making relevant judgements. Therefore, when a departure from a present path of development is sought for, access to new information is likely to be required. Results from an experimental study, addressing affordability and concept generation, indicated that individuals were influenced, by the provision of selective information, to make more cost considerations and even to change approach when generating new concepts. It was further recognized that weak abilities to estimate costs in a lifecycle and capability perspective likely hampered low-cost ambitions. The findings from this study are suggested to contribute to theory on product development, and to support affordability when new products are developed.
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| 2. |
- Carlsson, Anna K, 1966, et al.
(författare)
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Rollator related pedestrian single accidents and collision events in Sweden
- 2022
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Ingår i: Traffic Safety Research (TSR). - : Lund University. - 2004-3082. ; 2
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Tidskriftsartikel (refereegranskat)abstract
- Rollators (four-wheel walkers in USA; zimmer frames in UK) are commonly used as mobility aids for the elderly and people with a variety of disabilities. Pedestrian rollator users are a sub-group of Vulnerable Road Users (VRUs), although this group is rarely recognised in traffic safety contexts. The aim of this study is to extract and analyse rollator related pedestrian accident and injury data in Sweden. The results will provide valuable insight into the risks and obstacles rollator users are exposed to in the traffic environment and may in the long term contribute to improving the mobility of this group. The current study is based on data from 2,020 accidents involving 2,305 persons extracted from the Swedish Traffic Accident Data Acquisition (STRADA) database. For consistency reasons, a subset of data (N = 745) was analysed in order to investigate the development of accidents over a period of 10 years. Thereafter, each accident in the whole data set was registered as either single or collision. The results show that the number of rollator accidents in Sweden increased by approximately 80% during 2007–2016. Females dominate the injury statistics of single accidents, collisions, as well as fatal outcome, which may be due to exposure and/or differences in physical characteristics. Single accidents are much more common than collisions (n=1,668 and n=352, respectively) and the injury consequences are at least as serious. Data from the present study have revealed that the frequency of minor injuries (ISS 1–3) is 4.3 times, moderate (ISS 4–8) 6.0 times and serious injuries (ISS 9–15) 8.9 times higher in single accidents than in collisions. Fatal injuries are, however, more common in collision events (33 in comparison to 8). The vast majority of single accidents (99%) was due to falls. Many of the single accidents (29%) were caused by ground level differences (typically a curb) or due to surface conditions (19%). Collisions involved cars, trucks or buses in 91% of cases, occurring predominantly in car parks (31%) and on (zebra) crossings (30%). In 54% of cases the vehicles reversed into the rollator. Abbreviated Injury Scale (AIS) 3+ injuries were dominated by head (36%) and torso (33%) injuries in collision events, and hip fractures (71%) in single accidents. The present study shows that further research into rollator user related accidents, both single accidents and collision events, is required. In order to introduce appropriate measures, future work should follow up on accident and injury developments and further improve the quality of mobility aid related accident data in general. Improved stability and design, proper training programmes, effective maintenance services, development of a supporting infrastructure would contribute to increased safety for rollator users.
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| 3. |
- Dordlofva, Christo
(författare)
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Qualification Aspects in Design for Additive Manufacturing : A Study in the Space Industry
- 2020
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The aim of this research is to further the understanding of implications for product development and qualification when introducing additive manufacturing (AM) in the context of the space industry. Increased availability of AM machines and alluring potentials such as design freedom and cost-efficient product development and manufacturing has led to a rapid growth in the use of AM. However, the implementation of AM is hampered by lack of process understanding, implying uncertainties for engineers on how to design products for AM. Furthermore, the AM process chain (including e.g. post-processes) is not sufficiently developed and understood, adding further uncertainties. These uncertainties are a challenge when developing products for space applications, especially if they are critical for mission success and hence not allowed to fail. Such products and their manufacturing processes have to comply with strict requirements on verifying performance, quality, and reliability, i.e. product and process qualification. The purpose of this research is to investigate how qualification is addressed during product development in the space industry in order to find improved ways for engineers to explore the capabilities of AM to better understand its possibilities and limitations. The research is specifically focused on the use of powder bed fusion processes by companies developing and manufacturing sub-system components for space applications. It is limited to the manufacturing of components on Earth for use in space. The research approach is qualitative. Five studies provide the empirical foundation for the thesis, in which a total of four companies are included. In particular, one of the companies is studied in-depth, including a development project for a critical AM product. Individual interviews, workshops and focus groups are used for data collection. Furthermore, the in-depth study is based on a longitudinal presence at the company, providing the opportunity to gather data from project meetings and discussions. Collaborative action research with three of the companies provides a research setting to study the development of three AM products (of which the in-depth study is one) and how uncertainties related to the AM process can be addressed. Four aspects of how to address product qualification in Design for AM are deduced: (i) AM knowledge should be built through application-driven development processes, (ii) qualification should be accounted for early and to a larger extent, (iii) suitable and acceptable requirements should be defined through collaboration, and (iv) rapid manufacturing should be utilised to evaluate critical uncertainties. To support engineering teams on how to address these aspects, this thesis presents two contributions to the design field. The first is a design process utilising AM Design Artefacts (AMDAs) to identify, test and evaluate the AM-related uncertainties that are most pressing for a product. Through the iterative use of AMDAs, products designs are successively evolved, enabling a design which meets process capabilities and fulfils product requirements. The AMDA design process is part of the second contribution, a Design for Qualification framework that encourages a qualification-driven development approach for AM products. The framework includes six design tactics that provide guidance for its implementation. The tactics encourage an application-driven development process where qualification is considered early, and where successive steps are taken towards a thorough AM process chain understanding. The framework is designed based on the studied cases, and future research should focus on developing the framework and tactics further to facilitate implementation and wider applicability.
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| 4. |
- Farjana, Sadia, 1983, et al.
(författare)
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Dry film photoresist-based microfabrication : A new method to fabricate millimeter-wave waveguide components
- 2021
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Ingår i: Micromachines. - : MDPI AG. - 2072-666X. ; 12:3
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Tidskriftsartikel (refereegranskat)abstract
- This paper presents a novel fabrication method based on dry film photoresists to realize waveguides and waveguide-based passive components operating at the millimeter-wave frequency (30–300 GHz). We demonstrate that the proposed fabrication method has a high potential as an alternative to other microfabrication technologies, such as silicon-based and SU8-based micromachining for realizing millimeter-wave waveguide components. Along with the nearly identical transfer of geometrical structures, the dry film photoresist offers other advantages such as fewer processing steps, lower production cost, and shorter prototyping time over the conventional micromachining technologies. To demonstrate the feasibility of the fabrication process, we use SUEX dry film to fabricate a ridge gap waveguide resonator. The resonator is designed to exhibit two resonances at 234.6 and 284 GHz. The measured attenuation at 234 GHz is 0.032 dB/mm and at 283 GHz is 0.033 dB/mm for the fabricated prototype. A comparative study among different existing technologies indicates that the reported method can give a better unloaded Q-value than other conventional processes. The measured unloaded Q-values are in good agreement with the simulated unloaded Q-values. The signal attenuation indicates that SUEX dry film photoresists can be used to fabricate passive devices operating at millimeter-wave frequencies. Moreover, this new fabrication method can offer fast and low-cost prototyping. © 2021 by the authors.
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| 5. |
- Groth, Sanne Krogh, et al.
(författare)
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Introduction : Negotiating Noise Across Places, Spaces and Disciplines
- 2021
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Ingår i: Negotiating Noise : Across Places, Spaces and Disciplines - Across Places, Spaces and Disciplines. - : The Sound Environment Centre at Lund University. - 9789198711707 - 9789198711714 ; 19:19, s. 15-33
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 6. |
- Henje, Catharina, 1960-, et al.
(författare)
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Obstacles and risks in the traffic environment for users of powered wheelchairs in Sweden
- 2021
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Ingår i: Accident Analysis and Prevention. - : Elsevier. - 0001-4575 .- 1879-2057. ; 159
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Tidskriftsartikel (refereegranskat)abstract
- Objective: According to the European Union, fatal road accidents involving Vulnerable Road Users (VRUs) are equal in proportion to fatal car road accidents (46%). VRUs include individuals with mobility challenges such as the elderly and Powered Wheelchair (PWC) users. The aim of this interdisciplinary qualitative study was to identify obstacles and risks for PWC users by exploring their behaviour and experiences in traffic environments.Methods: Videos and in-depth interviews with 13 PWC users aged 20–66 were analysed for this study. The interviews and videos, which include real-life outdoor observations, originate from a qualitative study exploring experiences of PWC use on a daily basis in Sweden. Underlying causal factors to identified risks and obstacles were identified, based on human, vehicle (PWC) and environmental factors in accordance with the Haddon Matrix.Results: The results show significant potential for improvement within all three perspectives of the Haddon Matrix used in the analysis. Participants faced and dealt with various obstacles and risks in order to reach their destination. For example, this includes uneven surfaces, differences in ground levels, steep slopes, as well as interactions with other road users and the influence of weather conditions, resulting in PWC users constantly accommodating and coping with the shortcomings of the vehicle and the environment.Conclusions: There are still major challenges with regard to preventing obstacles and risks in the traffic environment for PWC users. To discern PWC users in traffic accident and injury data bases, a start would be to register type of aid used for persons involved in an accident. Furthermore, to emphasise PWC users’ role as VRUs, it may also be advantageous to describe them as drivers rather than users when navigating the traffic environment. Given the limited sample, further research covering more data from a broader perspective would be beneficial. By incorporating emerging knowledge of PWC users’ prerequisites and needs, and including them in research and traffic planning, the society will grow safer and more inclusive, and become better prepared for meeting future demands on accessibility from an aging population.
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| 7. |
- Holmlid, Leif, 1942
(författare)
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Generator for Large Fluxes of Kaons and Pions Using Laser-Induced Nuclear Processes in Ultra-Dense Hydrogen H(0)
- 2022
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Ingår i: Energies. - : MDPI AG. - 1996-1073. ; 15:24
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Tidskriftsartikel (refereegranskat)abstract
- Laser-induced nuclear reactions in ultra-dense hydrogen H(0) produce mesons with both relatively low kinetic energy and with high kinetic energy. The kaons have up to 100 MeV of kinetic energy, thus a velocity of 0.55 c. Each laser pulse of >0.1 J of energy and length of 5 ns produces 1013 mesons. The operation of the meson generator is here demonstrated by measuring all decay times for mesons in the ns range after induction by a pulsed laser. These decay times are the unique fingerprints of the mesons, and they also produce the kinetic energy of the mesons created from their time-dilated decay. The charged pion decay time at rest from this generator is measured to be 25.92 ± 0.04 ns (standard fit error), in reasonable agreement with the tabulated results of 26.033 ns. A similar accuracy is found for the other mesons as for the charged kaons, with 96 MeV of kinetic energy, at 14.81 ± 0.05 ns. The same general behaviour is found with both deuterium and normal hydrogen forming the ultra-dense phase H(0) on the laser target. This meson generator gives intense meson showers useful for many types of particle physics experiments at a small fraction of the cost of using particle accelerators. A particle accelerator would need an energy of at least 1021 eV to produce a similar shower of 1013 mesons. Thus, the described generator is among the most intense meson sources that exist. Other important applications include nuclear energy generation and particle (pion) radiation for cancer treatment.
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| 8. |
- Itkonen, Teemu, 1985, et al.
(författare)
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Characterisation of Motorway Driving Style Using Naturalistic Driving Data
- 2020
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Ingår i: Transportation Research Part F: Traffic Psychology and Behaviour. - : Elsevier BV. - 1369-8478. ; 69, s. 72-79
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Tidskriftsartikel (refereegranskat)abstract
- The study of measurable differences between drivers has ramifications for several subfields in traffic and transportation research. Better understanding of the variability in individual driving styles would be especially useful for understanding driver preferences, psychological mechanisms for vehicle control and for developing more realistic traffic simulations. In our study based on a large naturalistic data set, we investigated the driving style of 76 individuals driving in a motorway setting. We discovered that the majority of between-driver variation in keeping longitudinal and lateral safety margins, lane changing frequency, acceleration and speed preference, can be reduced to two dimensions, which we interpret as habitualised motives centred around mental effort and expediency.
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| 9. |
- Mattsson, Sandra, 1984, et al.
(författare)
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Using the compleXity index for improvement work : Investigating utilisation in an automotive company
- 2020
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Ingår i: International Journal of Manufacturing Research. - : Inderscience Enterprises Ltd.. - 1750-0591 .- 1750-0605. ; 15:1, s. 3-21
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Tidskriftsartikel (refereegranskat)abstract
- CompleXity index (CXI) is a method that measures perceived production complexity. CXI was applied in the assembly and material-handling department at a manufacturer in the automotive industry, followed by workshops. The aim of the article was, based on the results, to investigate if CXI could be used to capture and transmit a current situation and be used by the operators and managers for improvement work. A high CXI level was measured for most of the production areas. The areas were mainly perceived as complex due to work variance and station design. The workshops revealed that the operators felt identified with the results and thought the method could be used to discuss their situation in detail.
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| 10. |
- Pinzone, Marta, et al.
(författare)
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A framework for operative and social sustainability functionalities in Human- Centric Cyber-Physical Production Systems
- 2020
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Ingår i: Computers and Industrial Engineering. - : Elsevier BV. - 0360-8352. ; 139
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Tidskriftsartikel (refereegranskat)abstract
- In a near future where manufacturing companies are faced with the rapid technological developments of Cyber-Physical Systems (CPS) and Industry 4.0, a need arises to consider how this will affect human operators remaining as a vital and important resource in modern production systems. What will the implications of these orchestrated and ubiquitous technologies in production – a concept we call Cyber-Physical Production Systems (CPPS) – be on the health, learning and operative performance of human workers? This paper makes three main contributions to address the question. First, it synthesizes the diverse literature regarding CPS and social sustainability in production systems. Second, it conceptualizes a holistic framework, the CyFL Matrix, and outlines a guideline to analyze how the functionalities of a CPPS relate to operational and social sustainability-related performance impacts at different levels of analysis. Finally, it presents an industrial use case, which the CyFL Matrix and the related guidelines are applied to. In doing so, the study offers first support to researchers and managers of manufacturing companies willing to define suitable operational and social sustainability-related performances for Human-centric Cyber-Physical Production Systems of the future.
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