| 71. |
- Anderberg, Cecilia, et al.
(författare)
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Cylinder Liners and Consequences of Improved Honing
- 2006
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Ingår i: Proceedings of Nordtrib conference 2006, Helsingor, Danemark. ; , s. 13-
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Konferensbidrag (refereegranskat)abstract
- The demands on decreased environmental impact from vehicles are resulting in a strong push for decreased engine oil and fuel consumption. Engine oil and fuel consumption are to a great extent controlled by the topography of the cylinder liner surface.Recent engine tests have shown a promising reduction in oil consumption when using cylinder liners with a smoother finish than the current plateau honing.One approach to produce smoother liner surfaces is to replace SiC ceramic honing stones with diamond tools. However, event though the diamond honing process results in higher productivity, improved demands of quality control is needed to monitor the degree of cold worked material - “blechmantel” (German), and the resulting risk of increased wear and scuffing.A number of petrol and diesel engine cylinder liners have been mapped to be able to verify the quality and consequences, in terms of wear and function, of the honing process. A new mapping method, combining SEM images and quantitative image analysis with traditional 2D profilometry has been developed and tested in this study. The liners where tested in a reciprocating rig of 8 mm stroke and with a frequency of 10 Hz, simulating the top-dead center conditions in a running engine.The tests where carried out in high- and low pressure conditions with smooth respectively rough liner roughnesses against PVD coated piston rings. The developed surface mapping method was employed before and after the test to study effect of running-in wear on the surface, features characterized with the SEM- and the 2D profilometer.The results show that combining SEM- and profilometric methods gives a good picture of the effects of varying the cylinder liner pressure and roughness. The core roughness decrease more for diesel liners than for petrol liners. In average (rough and smooth liners) the diesel core roughness decrease 265% while the petrol liners average on a 60% decrease. Blechmantel- and Irregularities ratio show a high sensitivity to varying conditions and decrease 1180% to 100% for the diesel liners while the parameters increase between 106% to 18% for all the petrol liners. A probable cause is the more severe diesel high pressure run-in conditions are able to effectively “truncate” the plateaux and remove residing plastically deformed un-cut honing residues while the less severe petrol liner conditions not manage to remove the blechmantel and irregularities in an important extent.
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| 72. |
- Anderberg, Cecilia, et al.
(författare)
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Liner Surface Improvements for Low Friction Piston Ring Packs
- 2009
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Ingår i: Society of Tribologists and Lubrication Engineers annual meeting & exhibition 2009. - Red Hook, NY : Curran Associates, Inc.. - 9781615674374 ; , s. 455-459
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Konferensbidrag (refereegranskat)
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| 73. |
- Anderberg, Cecilia, et al.
(författare)
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Wear Resistance of Smooth Automotive Cylinder Liner Surfaces
- 2005
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Ingår i: World Tribology Congress III, Volume 2. - New York, NY : ASME Press. - 0791842029 ; , s. 603-604
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Konferensbidrag (refereegranskat)abstract
- Demands for decreased environmental impact from vehicles are resulting in a strong push for decreased engine oil, fuel consumption and weight. New machining and coating technologies have offered ways to attack these problems. Engine oil and fuel consumption are to a great extent controlled by the topography of the cylinder liner surface and it is therefore important to optimise this surface. Recent engine tests have shown a reduction in oil consumption when using cylinder liners with a smoother finish than that given by the current plateau honing. However, engine manufacturers are hesitant to introduce smoother liner surfaces because of fears of severe wear and scuffing. There is also the possibility that smoother liner surfaces may be more sensitive to the choice of piston ring finishes. This paper therefore seeks to investigate the functional performance and resistance to wear of these smooth cylinder liners and the mating top ring surfaces. Copyright © 2005 by ASME
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| 74. |
- Andersen, Naja Steen, et al.
(författare)
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Processes affecting genetic structure and conservation: a case study of wild and cultivated Brassica rapa
- 2009
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Ingår i: Genetic Resources and Crop Evolution. - Dordrecht : Springer Science and Business Media LLC. - 0925-9864 .- 1573-5109. ; 56:2, s. 189-200
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Tidskriftsartikel (refereegranskat)abstract
- When planning optimal conservation strategies for wild and cultivated types of a plant species, a number of influencing biological and environmental factors should be considered from the outset. In the present study Brassica rapa was used to illustrate this: to develop Scandinavian conservation strategies for wild and cultivated B. rapa, DNA-marker analysis was performed on 15 cultivated and 17 wild accessions of B. rapa plus 8 accessions of the cross compatible B. napus. The B. rapa cultivars were bred in Sweden and Finland in 1944-1997 and the wild B. rapa material was collected from Denmark, Sweden and United Kingdom. The B. napus accessions were bred within the last 20 years in the Scandinavian countries. Results were based on scoring of 131 polymorphic ISSR markers in the total plant material. A Bayesian Markov chain Monte Carlo (MCMC) approach implemented in NewHybrids demonstrated a clear distinction of B. rapa and B. napus individuals except for three individuals that seemed to be backcrosses. The backcrossed hybrids descended from two Swedish populations, one wild and one escaped. The overall pattern of genetic variation and structure in B. rapa showed that cultivated and wild B. rapa accessions formed two almost separated clusters. Geographical origin and breeding history of cultivars were reflected in these genetic relationships. In addition, wild populations from Denmark and Sweden seemed to be closely related, except for a Swedish population, which seemingly was an escaped cultivar. The study point to that many processes, e.g. spontaneous introgression, naturalisation, breeding and agricultural practise affected the genetic structure of wild and cultivated B. rapa populations.
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| 75. |
- Anderson, Sterling J., et al.
(författare)
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A Unified Approach to Semi-Autonomous Control of Passenger Vehicles in Hazard Avoidance Scenarios
- 2009
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Ingår i: IEEE 2009 IEEE International Conference on Systems, Man and Cybernetics, SMC 2009, VOLS 1-9. - Piscataway, N.J. : IEEE Press. - 9781424427932 ; , s. 2032-2037
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Konferensbidrag (refereegranskat)abstract
- This paper describes the design of unified active safety framework that combines trajectory planning, threat assessment, and semi-autonomous control of passenger vehicles into a single constrained-optimal-control-based system. This framework allows for multiple actuation modes, diverse trajectory-planning objectives, and varying levels of autonomy. The vehicle navigation problem is formulated as a constrained optimal control problem with constraints bounding a navigable region of the road surface. A model predictive controller iteratively plans the best-case vehicle trajectory through this constrained corridor. The framework then uses this trajectory to assess the threat posed to the vehicle and intervenes in proportion to this threat. This approach minimizes controller intervention while ensuring that the vehicle does not depart from a navigable corridor of travel. Simulated results are presented here to demonstrate the framework's ability to incorporate multiple threat thresholds and configurable intervention laws while sharing control with a human driver. ©2009 IEEE.
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| 76. |
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| 77. |
- Andersson, Janicke, 1975-
(författare)
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Konsten att leva längre : Föreställningar om livets förändring i handböcker 1700-1930
- 2007
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The aim of this thesis is to explore discursive changes in conceptions of life course and ageing. I am particularly concerned with the relationship between knowledge and power in the distribution of prolongevity and body- technologies, and as referential frame in the definition of normal and deviant bodies and behaviour. Following the historical processes this study includes advisory literature in the field of prolongevity from 1700-1930. As a conclusion I have distinguished four categories of legends in the material. In analyzing the legends: Antediluvian legends, Hyperborean legends, Fountain legends, and Centenarian legends. The legends of prolongevity intermediate ideas of human ageing in, and between cultures, On a meta-level there has been three discourses intertwining each other in the making of present images on prolongevity and successful ageing: Religion, Science and The Natural. In e discursive struggle during the studied years those components have been competing for domination and space on the prolongevity agenda. The advices reflect a belief in the possibility to transform by means of moderation and harmony; a belief that grew in the eighteenth century and enhanced during the following centuries. The aim was to improve human nature to an ennobled version of her self according to divine standards. Prolongevity was in 1700-1930 a question of reaching a pre-designated length of life given by God or Nature. Today we do not believe in pre-designated life-length we only believe in prolongation. We do want the paradise but we want it here on earth, and we want to be in charge.
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| 78. |
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| 79. |
- Andersson, Janicke, 1975-
(författare)
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Life extension as life long learning
- 2009
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Ingår i: ESA 2009, European society or European societies?. ; , s. 65-65
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Konferensbidrag (refereegranskat)abstract
- The aim of this paper is to examine some questions about knowledge and the concept of ?lifelong learning? raised during the work with my thesis. Questions to be discussed are whether everyday knowledge and information about how one ought to live in order to obtain a healthier and longer life can be viewed as a form of ?life long learning?. How can one interpret the field of life extension in aspects of education and governing strategies? With new technologies we are transforming the cyborg from the divergent to the normal. The study includes advisory literature from the 18th century till present times either written in, or translated to Swedish. In my thesis I explored discursive changes in conceptions of life course and ageing. In a sense life span embodies the boundaries of human existence, but furthermore, it symbolizes the system of reason of human existens in the name of the life-span. Hence, notions of the life span can reveal images and apprehensions of ageing and life itself. Meta level discourses of the life span provides information on apprehensions of the human existence. Historical handbooks, and literature on life-extension, provides interesting field for the study of ageing and humanity. My findings points out that we are approaching or constantly creating new ways of looking at and discipline the ageing process. The ageing process and the way to a longer life has become a field for educational strategies involving self technologies. Many of these technologies are founded on long lasting myths and legends that are constant even in contemporary advisory literature. The late modern model of advisory literature demands constant education and refection over life, identity and related fields. In this aspect our late modern lives have become a project of life long learning. Today we do not believe in pre-designated life-length we only believe in life extension. We do want the paradise but we want it here on earth, and we want to be in charge.
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| 80. |
- Andersson, Janicke, 1975-
(författare)
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Tänk på döden
- 2009
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Ingår i: Åldrande, åldersordning, ålderism. - Linköping : Linköpings universitet. - 9789173937139 ; , s. 222-237
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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