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Augmented reality smart glasses (ARSG) have been available as a commercial product since 2015. Many potential usage areas have been identified, including industrial use. The needs from industry have evolved, with more emphasis being put on sustainability. While ARSG can help improve efficiency and sustainability, there are also similarly associated costs to their implementation and use. This paper aims to present a process for how to choose ARSG for specific use cases as assembly operator support while considering the sustainability of their implementation. A narrative review of the literature was made to identify the current understanding of the environmental impact of ARSG, as well as what has been considered in regards to ARSG being integrated into a manufacturing environment. The analysis of the literature resulted in a proposed decision process. The decision process serves as a baseline for how to guide the decision of whether ARSG could be a suitable solution and, if so, what aspects to consider in the choosing of the ARSG model. Future work includes collaboration with industry to further improve the decision process based on empirical input.

Augmented Reality (AR) has shown its potential in supporting operators in manufacturing. AR-glasses as a platform both in industrial use are emerging markets, thereby making portable and hands-free AR more and more feasible. An important aspect of integrating AR as a support tool for operators is their acceptance of the technology. This paper presents the results of interviewing operators regarding their view on AR technology in their field and observing them working in automotive engine assembly and how they interact with current instructions. The observations and follow-up questions identified three main aspects of the information that the operators looked at: validating screw torque, their current assembly time, and if something went wrong. The interviews showed that a large amount of the operators were positive towards using AR in assembly. This has given an insight in both the current information interaction the operators do and their view on the potential in using AR. Based on these insights we suggest a mock-up design of an AR-interface for engine assembly to serve as a base for future prototype designs., QC 20181107

Robots are becoming more adaptive and aware of their surroundings. This has opened up the research area of tight human-robot collaboration, where humans and robots work directly interconnected rather than in separate cells. The manufacturing industry is in constant need of developing new products. This means that operators are in constant need of learning new ways of manufacturing. If instructions to operators and interaction between operators and robots can be virtualized this has the potential of being more modifiable and available to the operators. Augmented Reality has previously shown to be effective in giving operators instructions in assembly, but there are still knowledge gaps regarding evaluation and general design guidelines. This paper has two aims. Firstly it aims to assess if demonstrators can be used to simulate human-robot collaboration. Secondly it aims to assess if Augmented Reality-based interfaces can be used to guide test-persons through a previously unknown assembly procedure. The long-term goal of the demonstrator is to function as a test-module for how to efficiently instruct operators collaborating with a robot. Pilot-tests have shown that Augmented Reality instructions can give enough information for untrained workers to perform simple assembly-tasks where parts of the steps are done with direct collaboration with a robot. Misunderstandings of the instructions from the test-persons led to multiple errors during assembly so future research is needed in how to efficiently design instructions., QC 20170919

Hereditary myopathy with early respiratory failure (HMERF) and extensive myofibrillar lesions have been described in sporadic and familial cases and linked to various chromosomal regions. We describe the clinical manifestations, muscle histopathology and genetics in eight individuals from three apparently unrelated families with clinical and pathological features of HMERF. All patients had muscle weakness in the pelvic girdle, neck flexors, respiratory and trunk muscles, and the majority had prominent calf hypertrophy. Examination of pulmonary function showed decreased vital capacity. No signs of cardiac muscle involvement were found. Muscle histopathological features included marked muscle fibre size variation, fibre splitting, numerous internal nuclei and fatty infiltration. Frequent groups of fibres showed eosinophilic inclusions and deposits. At the ultrastructural level there were extensive myofibrillar lesions with marked Z-disc alterations. Whole exome sequencing in four individuals from one family revealed a missense mutation, g.274375, T>C; p.Cys30071Arg, in the titin gene, TTN. The mutation, which changes a highly conserved residue in the myosin binding A-band titin, was demonstrated to segregate with the disease in all three families. High density single nucleotide polymorphism arrays covering the entire genome demonstrated sharing of a 699 Mb haplotype, located in chromosome region 2q31 including TTN, indicating common ancestry of this novel and first disease-causing mutation in A-band titin associated with HMERF.

Intentional doping of aluminum in 4H and 6H SiC has been performed using a hot-wall CVD reactor. The dependence of aluminum incorporation on temperature, pressure, C/Si ratio, growth rate, and TMA flow has been investigated. The aluminum incorporation showed to be polarity dependent. The high aluminum incorporation on the Si-face is closely related to the carbon coverage on the SiC surface. Changes in process parameters changes the effective C/Si ratio close to the SiC surface. Increased growth rate and C/Si ratio increases the aluminum incorporation on the Si-face. Diffusion limited incorporation occurs at high growth rate. Reduced pressure increases the effective C/Si ratio, and at low growth rate, the aluminum incorporation increases initially, levels off at a critical pressure, and continues to decrease below the critical pressure. The aluminum incorporation showed to be constant in a temperature range of 50degreesC. The highest atomic concentration of aluminum observed in this study was 3 x 10(17) and 8 x 10(18) cm(-3) in Si and C-face, respectively., QC 20100525

The CVD growth of 4H SiC is investigated in a vertical hot-wall reactor in both up-flow (the chimney reactor) and down-flow (the inverted chimney) orientations. The growth rate and the nitrogen doping are studied for comparison. Under the investigated process conditions the growth mechanism is shown to be similar in these two reactor orientations. Only slight difference is observed in the temperature effect depending on the flow direction. Both reactor types have produced epilayers with high growth rates (10-35 mum/h) and low residual n-type doping (low 10(16) down to mid 10(13) cm(-3)) with comparable morphology. Dimensionless flow numbers are used to provide a qualitative analysis of the flow and heat transfer mechanisms in the vertical hot-wall system. Two-dimensional numerical simulation in a cylindrical geometry is conducted to demonstrate the flow and temperature profile with selected process parameters. Comparison of the experimental results in the chimney and the inverted chimney is performed to give insight into the fast epitaxial hot-wall growth., QC 20100525

Intentional doping with nitrogen of 4H- and 6H-SiC has been performed using a hot-wall CVD reactor. The nitrogen doping dependence on the temperature, pressure, C/Si ratio, growth rate and nitrogen flow has been investigated. The nitrogen incorporation for C-face material showed to be C/Si ratio independent, whereas the doping decreased with increasing C/Si ratio for the Si-face material in accordance with the site-competition model. The nitrogen incorporation was constant in a temperature window of 75degreesC on Si-face material indicating a mass transport limited incorporation. Increasing the growth rate resulted in a decrease of nitrogen incorporation on Si-face but an increase on C-face material. Finally, a comparison between previously published results on cold-wall CVD-grown material and the present hot-wall-grown material is presented., QC 20100525

Intentional p-type doping of SiC has been performed by using trimethylaluminum as dopant source. A comprehensive investigation of the aluminum incorporation dependency on temperature, pressure, C/Si ratio and growth rate in a horizontal hot-wall CVD reactor has been made. The incorporation mechanism for 4H and 6H-SiC both for Si- and C-face material is presented., International Conference on Silicon Carbide and Related Materials, TSUKUBA, JAPAN, OCT 28-NOV 02, 2001 NR 20140805

The growth of device quality epitaxial layers requires precise control of the thickness and doping uniformity. By using simulations a better understanding of the growth process can be achieved and process optimization may be possible. The present work uses an extensive chemistry model, to accurately predict growth rates of epitaxial layers grown by chemical vapor deposition. Simulations are made in three dimensions to accurately model the horizontal reactor used in the experiments. Experimental results show four main growth zones, which are characterized by different morphological defects. Certain defects can be attributed to either silicon rich or carbon rich deposition, which is confirmed by X-ray photospectroscopy measurements. Different cases are studied, changing the total pressure in the growth chamber.

Objectives - The existence of chronic neuroborreliosis is controversial. The aim of our study was to investigate the existence and kind of persistent symptoms in patients previously treated because of neurological symptoms as a result of neuroborreliosis. Material and methods - A total of 106 patients with neuroborreliosis, according to established criteria, and a control group of 123 patients with Borrelia induced erythema migrans diagnosed in a general practitioner office were studied. A questionnaire was sent to patients and controls concerning their health situation. Time from onset of neurological symptoms to the questionnaire sendout was 32 months (mean) for the patients with neuroborreliosis and 33 months (mean) for the controls. Results - Fifty per cent of the individuals in the patient group compared with 16% of the individuals in the control group showed persistent complaints after their Borrelia infection (P < 0.0001). The most significant differences between the groups were the presence of neuropsychiatric symptoms such as headache, attention problems, memory difficulties and depression. Paresthesia, pain and persistent facial palsy was also significantly more common in patients treated because of neuroborreliosis. Conclusion - Our study shows that persisting neurological symptoms are common after a neuroborreliosis infection. The pathological mechanisms that lay behind the development of chronic symptoms, however, are still uncertain.

The effect of reactor orientation on the CVD growth of JH SIC is investigated. Compared with the up-flow orientation (the chimney reactor), the down-flow orientation (the inverted chimney) shows similar growth rate dependencies on C/Si ratio and pressure. The activation energy of the growth rate in the inverted chimney is Lower than that in the chimney. The inverted chimney also produces epilayers with high growth rates (10 - 30 mum/h) and low residual doping (low 10(16) down to mid 10(13) cm(-3)). The epilayer morphology is comparable with that of the chimney samples. A qualitative analysis is performed on the heat transfer mechanisms in these two reactor orientations in terms of dimensionless flow numbers.