| 1. |
- Johansson, Carl-Johan, et al.
(författare)
-
Sågverksnytt nr 1
- 2013
-
Rapport (övrigt vetenskapligt/konstnärligt)
|
|
| 2. |
- Johansson, Emil, et al.
(författare)
-
Influence of Resin Composition on the Defect Formation in Alumina Manufactured by Stereolithography
- 2017
-
Ingår i: Materials. - : MDPI AG. - 1996-1944. ; 10:2
-
Tidskriftsartikel (refereegranskat)abstract
- Stereolithography (SL) is a technique allowing additive manufacturing of complex ceramic parts by selective photopolymerization of a photocurable suspension containing photocurable monomer, photoinitiator, and a ceramic powder. The manufactured three-dimensional object is cleaned and converted into a dense ceramic part by thermal debinding of the polymer network and subsequent sintering. The debinding is the most critical and time-consuming step, and often the source of cracks. In this study, photocurable alumina suspensions have been developed, and the influence of resin composition on defect formation has been investigated. The suspensions were characterized in terms of rheology and curing behaviour, and cross-sections of sintered specimens manufactured by SL were evaluated by SEM. It was found that the addition of a non-reactive component to the photocurable resin reduced polymerization shrinkage and altered the thermal decomposition of the polymer matrix, which led to a reduction in both delamination and intra-laminar cracks. Using a non-reactive component that decomposed rather than evaporated led to less residual porosity.
|
|
| 3. |
- Eriksson, Jonny, 1963, et al.
(författare)
-
Development of mortars in Sweden during the period 1800 to 1950
- 2016
-
Ingår i: 4th Historic Mortars Conference HMC 2016. Santorini, Greece, 10-12 October, 2016.. ; , s. 204-210
-
Konferensbidrag (refereegranskat)abstract
- The objective with the present project was to combine studies of textbooks and masonry constructions with laboratory analyses of historical mortars from the time period 1800 to 1950. The objective was to investigate the development of knowledge and craftsmanship of the mason during this period. The three different sources display the same trends from binder rich to binder poor and to mortars based on cement and lime mixes. There was a change from a complex and varying use of different mortars in the 19th century to a simplified and standardized use in the 20th century. This process also includes a change to a centralised and industrialized production of binders. A consequence of this was that a loss of the craftmans knowledge of how to handle different hydraulic binders and pozzolans. The later part of the period was characterised in a loss of knowledge in this aspect for all actors working with masonry and renders.
|
|
| 4. |
- Flansbjer, Mathias, et al.
(författare)
-
Mechanical behaviour of concrete piles affected by sulphate attack
- 2013
-
Ingår i: Proceeding of the International IABSE Conference. - 9783857481239 ; , s. 389-392, s. 556-557
-
Konferensbidrag (refereegranskat)abstract
- Assessing the remaining service life is vital for the planning of maintenance of concrete constructions in aggressive environments. Here we present results from testing of two concrete piles affected by sulphate attack in marine environment. A multi-method approach going from micro scale to structural level has been applied. The crack propagation was monitored during loading by means of DIC and AE. After the test crack patterns was studied using fluorescence microscopy. Furthermore, non-linear finite element analysis at the structural level was used to study the influence of the chemical attack on the response of concrete piles.
|
|
| 5. |
- Jarebrant, Caroline, et al.
(författare)
-
ErgoVSM: A Tool for Integrating Value Stream Mapping and Ergonomics in Manufacturing
- 2016
-
Ingår i: Human Factors and Ergonomics in Manufacturing & Service Industries. - : Wiley. - 1090-8471 .- 1520-6564. ; 26:2
-
Tidskriftsartikel (refereegranskat)abstract
- Value stream mapping (VSM) is a Lean tool aiming at waste reduction. Previous research suggests that the use of VSM may result in work intensification and thus an increased risk for the workers of developing work-related musculoskeletal disorders (MSD). In the current study, VSM was developed to also consider physical exposure in the analyzed production system (ErgoVSM). As the VSM, ErgoVSM is based on a participatory approach. ErgoVSM was tested in a Swedish manufacturing company. The results suggest that ErgoVSM catalyzes change processes to include intervention proposals emphasizing ergonomics in addition to waste reduction. Thus, ErgoVSM appeared useful for the investigated target group of production engineers and experienced operators. The performance improvements suggested when using the ordinary VSM seemed not to be hampered by adding the ergonomics complement. However, the use of ErgoVSM was somewhat more time-consuming than the use of VSM. In conclusion, ErgoVSM is suggested as a feasible tool to be used by production engineers and experienced operators for including ergonomics considerations in the rationalization process.
|
|
| 6. |
|
|
| 7. |
- Niklasson, Annika, 1977, et al.
(författare)
-
Air Pollutant Concentrations and Atmospheric Corrosion of Organ Pipes in European Church Environments
- 2008
-
Ingår i: Studies in Conservation. - 0039-3630 .- 2047-0584. ; 53:1, s. 24-40
-
Tidskriftsartikel (refereegranskat)abstract
- Abstract: The atmospheric environment inside and outside historical organs in several European regions is reported. In each region, comparisons were made between an instrument suffering organ pipe corrosion and an organ without corrosion problems. Concentrations of acetic acid (ethanoic acid), formic acid (methanoic acid), acetaldehyde (ethanal), formaldehyde (methanal) and other volatile organic compounds in the organ environment were determined using active sampling. Temperature and relative humidity were recorded. In addition, polished metal samples that mimic the material used in the historical organ pipes have been exposed in the organ wind systems for up to 22 months. High concentrations of acetic acid and formic acid vapours are present in the wind system of the corroded organs. Acetaldehyde and formaldehyde are also present in smaller amounts. The main source of acetic acid is the wood from which the wind system is built. In contrast, formic acid is generated in the chruch environment outside the wind system. The results show that the two organic acids play an important role in the atmospheric corrosion of organ pipes. It is suggested that the corrosion of lead pipes in historical organs can be effectively reduced by removing the sources of gaseous acetic acid and formic acid in the wind system and in the chruch environment.
|
|
| 8. |
- Olsson, Anders, 1973-, et al.
(författare)
-
Prediction of timber bending strength and in-member cross-sectional stiffness vartiation on basis of local wood fibre orientation
- 2013
-
Ingår i: European Journal of Wood and Wood Products. - : Springer. - 0018-3768 .- 1436-736X. ; 71:3, s. 319-333
-
Tidskriftsartikel (refereegranskat)abstract
- Machine strength grading of structural timber is based upon relationships between so called indicating properties (IPs) and bending strength. However, such relationships applied on the market today are rather poor. In this paper, new IPs and a new grading method resulting in more precise strength predictions are presented. The local fibre orientation on face and edge surfaces of wooden boards was identified using high resolution laser scanning. In combination with knowledge regarding basic wood material properties for each investigated board, the grain angle information enabled a calculation of the variation of the local MOE in the longitudinal direction of the boards. By integration over cross-sections along the board, an edgewise bending stiffness profile and a longitudinal stiffness profile, respectively, were calculated. A new IP was defined as the lowest bending stiffness determined along the board. For a sample of 105 boards of Norway spruce of dimension 45 × 145 × 3600 mm, a coefficient of determination as high as 0.68-0.71 was achieved between this new IP and bending strength. For the same sample, the coefficient of determination between global MOE, based on the first longitudinal resonance frequency and the board density, and strength was only 0.59. Furthermore, it is shown that improved accuracy when determining the stiffness profiles of boards will lead to even better predictions of bending strength. The results thus motivate both an industrial implementation of the suggested method and further research aiming at more accurately determined board stiffness profiles.
|
|
| 9. |
|
|
| 10. |
|
|
