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Understanding “efficiency roll-off” (i.e., the drop in emission efficiency with increasing current) is critical if efficient and bright emissive technologies are to be rationally designed. Emerging light-emitting electrochemical cells (LECs) can be cost- and energy-efficiently fabricated by ambient-air printing by virtue of the in situ formation of a p-n junction doping structure. However, this in situ doping transformation renders a meaningful efficiency analysis challenging. Herein, a method for separation and quantification of major LEC loss factors, notably the outcoupling efficiency and exciton quenching, is presented. Specifically, the position of the emissive p-n junction in common singlet-exciton emitting LECs is measured to shift markedly with increasing current, and the influence of this shift on the outcoupling efficiency is quantified. It is further verified that the LEC-characteristic high electrochemical-doping concentration renders singlet-polaron quenching (SPQ) significant already at low drive current density, but also that SPQ increases super-linearly with increasing current, because of increasing polaron density in the p-n junction region. This results in that SPQ dominates singlet-singlet quenching for relevant current densities, and significantly contributes to the efficiency roll-off. This method for deciphering the LEC efficiency roll-off can contribute to a rational realization of all-printed LEC devices that are efficient at highluminance.

Purpose - The primary aim of this study is to explore the intricacies of knowledge management within theframework of large-scale digital and agile projects. This was undertaken within the context of a specificmanufacturing project referred to as 'Project X'. The project provided an opportunity to delve into the processesof knowledge creation, sharing, and utilization, and to identify the barriers of these processes, creating a morecomprehensive understanding of the subject. Method - An abductive exploratory single case study approach was employed, focusing on Company X as thesingle case company. The study utilized a combination of data collection methods, including document analysisand qualitative interviews. The interviews were conducted in three waves: exploratory, semi-structured, andvalidatory. The data obtained from the interviews and document analysis were analysed using thematic analysisand content analysis. Findings - The study found that knowledge creation is impeded by lack of communication and managingresources. Knowledge sharing was hindered by a changing project landscape and the lack of 'knowledgechampions'. Knowledge utilization was found to be affected by lack of structure, internal resistance to change,and a lack of knowledge repository. Theoretical contribution - This study contributes to the knowledge management literature by providing insightsinto the complexities of managing knowledge within the context of digital and agile projects in the manufacturingindustry. It underscores the pivotal role of communication, resource management, and organizational culture ineffective knowledge management and opens new avenues to explore and understand these areas. Managerial implications - From a practical standpoint, this study underscores the need for organizations toprioritize effective communication and resource management in the pursuit of effective knowledge management.Organizations should work towards creating a favourable environment for knowledge sha

Denna uppsats tecknar hur kunskapsbegrepp av olika slag med avseende på litteraturstudiet inom svenskämnet har konstruerats genom läro-, ämnes- och kursplaner från och med 1970 års läroplan för gymnasieskolan fram till och med den från 2011. Genom att i en närläsning tillämpa idealty- piska begrepp från läroplansteorin visas det hur litteraturen fyllt ett antal olika funktioner under 1900-talets andra hälft. Denna utveckling kännetecknas av ett essentialistiskt hu- manistiskt perspektiv å ena sidan, och ett instrumentellt socialt å andra, där den senare har kommit att bli den domi- nerande ämneskonceptionen i våra dagar.

The next generation of emissive devices should preferably be efficient, low-cost, and environmentally sustainable, and as such utilize all electrically generated excitons (both singlets and triplets) for the light emission, while being free from rare metals such as iridium. Here, we report on a step toward this vision through the design, fabrication, and operation of a host guest light-emitting electrochemical cell (LEC) featuring an organic thermally activated delayed fluorescence (TADF) guest that harvests both singlet and triplet excitons for the emission. The rare-metal-free active material also consists of a polymeric electrolyte and a polymeric compatibilizer for the facilitation of a cost-efficient and scalable solution-based fabrication, and for the use of air-stable electrodes. We report that such TADF-LEC devices can deliver uniform green light emission with a maximum luminance of 228 cd m(-2) when driven by a constant-current density of 770 A m(-2), and 760 cd m(-2) during a voltage ramp, which represents a one-order-of-magnitude improvement in comparison to previous TADF-emitting LECs.