| 31. |
- Behboudi, Afrouz, 1967, et al.
(författare)
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Evolutionary aspects of the genomic organization of rat chromosome 10.
- 2002
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Ingår i: Cytogenetic and genome research. - : S. Karger. - 1424-8581 .- 1424-859X. ; 96:1-4, s. 52-9
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Tidskriftsartikel (refereegranskat)abstract
- Using FISH and RH mapping a chromosomal map of rat chromosome 10 (RNO10) was constructed. Our mapping data were complemented by other published data and the final map was compared to maps of mouse and human chromosomes. RNO10 contained segments homologous to mouse chromosomes (MMU) 11, 16 and 17, with evolutionary breakpoints between the three segments situated in the proximal part of RNO10. Near one of these breakpoints (between MMU17 and 11) we found evidence for an inversion ancestral to the mouse that was not ancestral to the condition in the rat. Within each of the chromosome segments identified, the gene order appeared to be largely conserved. This conservation was particularly clear in the long MMU11-homologous segment. RNO10 also contained segments homologous to three human chromosomes (HSA5, 16, 17). However, within each segment of conserved synteny were signs of more extensive rearrangements. At least 13 different evolutionary breakpoints were indicated in the rat-human comparison. In contrast to what was found between rat and mouse, the rat-human evolutionary breaks were distributed along the entire length of RNO10.
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| 32. |
- Bengtsson, Anders, 1988, et al.
(författare)
-
Counterterms in gravity in the light-front formulation and a D=2 conformal-like symmetry in gravity
- 2013
-
Ingår i: Journal of High Energy Physics. - : Springer Science and Business Media LLC. - 1029-8479 .- 1126-6708. ; 58:5-6, s. 485-501
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper we discuss gravity in the light-front formulation (light-cone gauge) and show how possible counterterms arise. We find that Poincare invariance is not enough to find the three-point counterterms uniquely. Higher-spin fields can intrude and mimic three-point higher derivative gravity terms. To select the correct term we have to use the remaining reparametrization invariance that exists after the gauge choice. We finally sketch how the corresponding programme for N = 8 Supergravity should work.
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| 33. |
- Bengtsson, Magnus, 1973, et al.
(författare)
-
ADVANCED MATERIAL MODELLING IN CRUSHING PLANTS USING REAL TIME ALGORITHMS
- 2015
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Ingår i: Computational Modelling 2015, MEI conference.
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- In process control of crushing plants the traditional control is focused on stability control ofsingle machines and not on controlling material utilization. The reason for this is that the use ofmaterial property models is not that well known. The material models describe properties as e.g.capacity over time for a given product and this may depend on many parameters and dynamic effectsin the process. Due to this it is complicated to model and thus a methodology is needed to solve thisproblem. In this paper a novel method for modeling the current effect that the production units haveon the material presented. The paper presents a methodology how to use process data from SCADAsystem to analyze and suggest dynamic material model properties in real time.
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| 34. |
- Bengtsson, Magnus, 1973, et al.
(författare)
-
Cost And Performance Optimization Of A Tertiary Crushing Stage
- 2015
-
Ingår i: ESCC 2015 Conference. - Göteborg : Chalmers University of Technology. - 9789188041012
-
Konferensbidrag (refereegranskat)abstract
- There is increasing demand to optimise performance and profit of crushing plants. Research in this area has resulted in the development of numerous optimisation tools, and resent research has shown that the quality aspects of production have great influence on the optimisation results. The quality, cost, profit and capacity of a product is influenced by several parameters, and in order to control all of these parameters it is necessary to use some sort of optimisation software. In this paper, a novel approach use the parameters cost, profit, capacity and quality in order to perform a multi objective optimization of a crushing plant is presented. As an example a tertiary crushing stage consistent of a cone crusher and a vertical shaft impact crusher (VSI) is used as base for the designed objective function. The process has a given set of constraints that represents the conditions normal in these type of crushing applications. The first step in this paper is to identify if the range of the constraints can cause undesirable production costs when reaching for a given product property. The next step in the optimization shows how a strategy for relaxing constraint can increase overall productivity and still reach certain product properties. The conclusions made in this work are that multi objective optimization is essential when optimizing crushing plant production against multiple objectives. Relaxation of constraints can increase the overall performance of the crushing plant.
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| 35. |
- Bengtsson, Magnus, 1973, et al.
(författare)
-
Framework for material modelling in a processing plant
- 2015
-
Ingår i: Computational Modelling ‘15.
-
Konferensbidrag (refereegranskat)abstract
- Material modelling within a crushing plant is closely dependent on both manual and automatic operations as well as a close follow up on the utilization of the plant performance from a management perspective. The desire to fully be able to utilize the crushing plant with respect e.g. to material handling is limited due to the lack of possibility to fully observe actions within the process. There are large quantities of data that can be monitored in the crushing plant SCADA system. However the data collected are governed by the quantity of actual sensors in the process. The aim with this paper is to propose a method for how-to pre-process the automatically gathered SCADA data in order to fill up dynamic models for process simulations. There is a fundamental need to increase the resolution of how the crushing plant behaves. This will be structured as a framework for analysing and suggesting model improvements that will increase the utilization and decrease both manual operations and give better performance when controlling the process.
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| 36. |
- Bengtsson, Magnus, et al.
(författare)
-
Improving yield and shape in a crushing plant
- 2009
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Ingår i: Minerals Engineering. - : Elsevier BV. - 0892-6875 .- 1872-9444. ; 22:7-8, s. 618-624
-
Tidskriftsartikel (refereegranskat)abstract
- There is increasing demand to optimise yield and increase capacity of crushing plants. Research in this area has resulted in the development of numerous optimisation tools, and resent research has shown that the economic aspects of production have great influence on the optimisation results. The profitability of a product is influenced by several parameters, and control of all these parameters is necessary to use some sort of optimisation software. In this paper, we present a case study of a typical crushing plant, with the goal of reducing the number of crusher while keeping the plant capacity and quality. By reducing the number of crusher the plant will need less maintenance which will decrease the operating costs. The article presents a method to combine crushing plant simulation and optimisation with quality and economic considerations in order to successfully study alternative configurations of the plant.
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| 37. |
- Bengtsson, Magnus, 1973, et al.
(författare)
-
Improving Yield and Shape in a Crushing Plant
- 2009
-
Ingår i: Proceedings of 12th European Symposium on Comminution and Classification (ESCC2009).
-
Konferensbidrag (refereegranskat)abstract
- There is increasing demand to optimise yield and increase capacity of crushing plants. Research in this area has resulted in the development of numerous optimisation tools, and resent research has shown that the quality aspects of production have great influence on the optimisation results. The quality and capacity of a product is influenced by several parameters, and in order to control all these parameters it is necessary to use some sort of optimisation software. In this paper, a novel approach to analyse parameters influence on product capacity and quality is presented. As an example a cone crusher and a vertical shaft impact crusher (VSI) is simulated in a tertiary stage. The simulation shows how capacity and product quality for a range of products will be affected when a parameter is changed. The paper also shows how wear will affect product capacity and quality.
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| 38. |
- Bengtsson, Magnus, 1973, et al.
(författare)
-
Influence of throw and compression ratio on particle shape - A full scale investigation and laboratory tests
- 2010
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Ingår i: Minerals Engineering. - : Elsevier BV. - 0892-6875 .- 1872-9444. ; 23:7, s. 549-557
-
Tidskriftsartikel (refereegranskat)abstract
- The machine parameters of throw and eccentric speed affect the particle shape. Their influence on particle shape is however not fully investigated. Preliminary tests on a full-scale crusher had shown certain trends in regard to the flakiness of the product (Fig. 1). These effects were investigated in detail by means of a series of piston-and-die tests, followed by modelling of the laboratory data. An empirical model of a crusher was developed which links the product size distribution and the shape of the particles to operating parameters. The simulator produced trends which were similar to the full-scale data. The throw and eccentric speed affects the utilised compression acting on the rock/rock-bed. This paper presents a method suitable for characterizing the compressive breakage behaviour of rock materials during form conditioned compression. In this method, size reduction is primarily related to geometric compression. The method provides a complete description of the breakage characteristics of the tested rock material when compressive crushing is employed. The results can be used for modelling and simulation purposes in the design of crushing equipment or crushing plants. A novel approach to optimise form conditioned crushing in order to achieve an acceptable particle size and shape is presented. The paper concludes that inter-particle breakage in combination with high compression ratio is beneficial for the particle shape. The full scale tests support this since an increase in throw improves particle shape for particles subjected to inter-particle breakage. © 2009 Elsevier Ltd. All rights reserved.
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| 39. |
- Bengtsson, Magnus, et al.
(författare)
-
Measuring characteristics of aggregate material from vertical shaft impact crushers
- 2006
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Ingår i: Minerals Engineering. - : Elsevier BV. - 0892-6875 .- 1872-9444. ; 19:15, s. 1479-1486
-
Tidskriftsartikel (refereegranskat)abstract
- Natural gravel has traditionally been the main choice of material for Swedish concrete manufacturers. However, due to the fact that natural gravel also acts as a fresh water filter, the deposits are limited. The obvious question is how to compare machine made and natural gravel in terms of particle shape, rheology and other material characteristics. This paper will present some methods and results that demonstrate performance of different machine made rock materials. Particle shape characteristics were assessed from flow measurements in a standard cone. The vertical shaft impact crusher (VSI) produces gravel that is a good alternative to natural gravel. The quality of the material and the particle shape seem to meet concrete producers’ demands.
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| 40. |
- Bengtsson, Magnus, 1973, et al.
(författare)
-
Model of banana screen for robust performance
- 2016
-
Ingår i: Minerals Engineering. - : Elsevier BV. - 0892-6875 .- 1872-9444. ; 91, s. 66-73
-
Tidskriftsartikel (refereegranskat)abstract
- Screens are an important production unit in crushing plants. The performance of the screen is essential to the performance of the crushing plant. In this paper a mechanistic model of a banana screen is described and a novel model for screen deck configuration is presented. The developed model can be used for optimization of a screen so that it has the best possible performance with respect to different feeding conditions, in order to obtain a desired separation. The simulation results were compared to full scale test data and the conclusions from this comparison is that the screen model needs further parameters to handle the necessary screen deck configuration. An initial static model was derived to explain how the screen deck configuration will affect the screen efficiency. The modification of the screen deck parameters resulted in a better correlation both regarding size distribution and predicted capacity.
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