| 1. |
- Adam, J., et al.
(author)
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Two-pion femtoscopy in p-Pb collisions at root(NN)-N-S=5.02 TeV
- 2015
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In: Physical Review C (Nuclear Physics). - 0556-2813. ; 91:3
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Journal article (peer-reviewed)abstract
- We report the results of the femtoscopic analysis of pairs of identical pions measured in p-Pb collisions at root(NN)-N-S = 5.02 TeV. Femtoscopic radii are determined as a function of event multiplicity and pair momentum in three spatial dimensions. As in the pp collision system, the analysis is complicated by the presence of sizable background correlation structures in addition to the femtoscopic signal. The radii increase with event multiplicity and decrease with pair transverse momentum. When taken at comparable multiplicity, the radii measured in p-Pb collisions, at high multiplicity and low pair transverse momentum, are 10%-20% higher than those observed in pp collisions but below those observed in A-A collisions. The results are compared to hydrodynamic predictions at large event multiplicity as well as discussed in the context of calculations based on gluon saturation.
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| 2. |
- Holmberg, M., et al.
(author)
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Evaluation of pre-grouting for the city line project using the RTGC method
- 2012
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In: ISRM International Symposium - EUROCK 2012. - : International Society for Rock Mechanics.
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Conference paper (peer-reviewed)abstract
- An access tunnel for the City Line project in Stockholm was excavated in the early parts of 2010. The works also included pre-grouting with cement. The performance of pre-grouting operation was evaluated for 14 continuous fans that included 326 grouted holes. A method called “Real Time Grouting Control (RTGC)”was used in the analysis. It is shown how the RTGC method can be used to investigate the effectiveness of existing stop criteria. It is first time an evaluation using RTGC carried out in this magnitude. The water inflow to the tunnel after grouting satisfied requirements. The grouting effect is quantified by assessments of the average conductivity of the rock mass and of the grout spread outside the tunnel. The evaluation indicates that the stop criteria in the design were chosen conservatively relative to the achieved grouting results. A model is discussed where the required grout spread is used as a design parameter to quantify the potential for reducing the pumping time.
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| 3. |
- Enckell, P H, et al.
(author)
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The dispersal pattern of an anthropochorous species: Genetic variation in populations of Lumbricus terrestris L. (Lumbricidae) in the Faroe Islands
- 1986
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In: Hereditas. - : Springer Science and Business Media LLC. - 0018-0661 .- 1601-5223. ; 104:2, s. 253-261
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Journal article (peer-reviewed)abstract
- Ten populations of the anthropochorous Lumbricus terrestris L. (Lumbricidae) from six islands in the Faroes were scored for enzyme variation by electrophoresis. The allele frequencies were analyzed by cluster analysis and information entropy relationships. There was a significant heterogeneity in allele frequencies among the samples. Four groups could be distinguished in the cluster analysis of which one was larger (at least five sites); two sites were defined as outliers. Information entropy showed that the allele frequency data were structured differently over the sites and that the most non-random site was also one of the outliers in the cluster space. The main group in the cluster analysis also forms a geographically central group in the islands. These results are discussed against the known colonization history of the Faroes. It is concluded that the genetic variation pattern does not indicate any single point of invasion of L. terrestris into the islands. Rather, it shows that former and present-day communications between the islands are responsible for similarities and dissimilarities in genetic variation in the L. terrestris populations.
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| 4. |
- Ma, J., et al.
(author)
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Deformation of anchor-sheet pile wall retaining system at deep excavations in soft soils overlying bedrock
- 2010
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In: Deep and underground excavations. - Reston, VA : American Society of Civil Engineers (ASCE). - 9780784411070 ; , s. 126-131
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Conference paper (peer-reviewed)abstract
- This contribution gives a case study on the deformations of anchor back-tied steel sheet pile walls and retained soils at deep excavations in soft soils overlying bedrock in Stockholm. Instrumentation results show the deformation of the retained soils is larger than that from similar case histories. The monitored anchor stresses increase quickly in the early stages of excavation and decease gradually to a constant value during later stages, while the lateral displacements of the sheet pile walls increase gradually. The results of both monitoring and numerical analysis show that this dynamic feature becomes weak as the thickness of the underlying soils is small. The decrease of the anchor stresses is mainly due to the flectional behavior of the sheet pile wall and the stress rotation in the retained soils.
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| 5. |
- Ma, J. Q., et al.
(author)
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Behavior of sheet pile walls at deep excavations in soft soils overlying hard rock in Stockholm
- 2008
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In: Int. Conf. Comput. Methods Adv. Geomech.. - 9781622761760 ; , s. 3922-3929
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Conference paper (peer-reviewed)abstract
- The deformation of retained soil is of importance for the design of a deep excavation in soft soil. The influence of bedrock underlying the soils on the behavior of the retaining wall needs proper evaluation. This contribution shows a case study on deep excavation in soft soil overlying bedrock at the South Link Infrastructure Project in Stockholm. The behavior of sheet pile walls at the South Link shows that both lateral displacement and settlement are larger than the magnitude from similar case histories. Exemplified by section 1/840N, the features of lateral displacement increment are analyzed with monitoring and PLAXIS simulating results. The analysis results indicate that the beneficial influence of bedrock may be overshadowed by the low strength of soils in which excavation occurs.
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| 6. |
- Ma, J. Q., et al.
(author)
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Concept of the NATM in China and its influence on the numerical analyses on tunnel design and construction with FEM
- 2008
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Conference paper (peer-reviewed)abstract
- The concept of NATM has been widely accepted in the fields of both tunnel and underground structure design and construction in China since 1980s. Similarly in the world wide, there are several definitions and explanations in both academy and construction markets. In practice, there is usually a big gap between involved parties in understanding the meaning of NATM. In this contribution, the concept of NATM in China is first reviewed. The influence of the concept of NATM on the numerical analyses on tunnel design and construction is briefly described in terms of FEM. Based on the practical situation in China, discussion focuses on the disadvantage of NATM application. The main causation is due to the different meaning under same name in practice. Suggestions are proposed to the educators who are disseminating the concept of NATM.
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| 7. |
- Ma, J. Q., et al.
(author)
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Influence of the schistous structure of gneiss on the rockburst of Qinling tunnels in China
- 2009
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In: ISRM International Symposium on Rock Mechanics, SINOROCK 2009. - : International Society for Rock Mechanics.
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Conference paper (peer-reviewed)abstract
- Two extra-long tunnels, with two tubes each, were excavated in a corridor of about 200 m in Qinling Mountain in the central part of China, for railway and road lines from Xi'an to Ankang, respectively. During tunnel excavations, severe rockbursts have occurred in several gneiss sections. The rockburst features indicate the pronounced effect of the fabric of the schistous structure of gneiss on the strength and deformation characteristics of intact rocks. The analysis on the geological conditions in terms of initial geostatic stress, rock strength and the occurrence of the gneiss foliation planes indicates that the schistous structure of gneiss is in favor to the severe rockburst in the section of magmatic gneiss with large overburden. The influence of anisotropic feature of the gneiss on the rockburst becomes significant on the condition that a large initial principal stress is nearly parallel to the foliation planes and the foliation structure composed mainly of biotite and quartz provides a weak plane to brittle failure.
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| 8. |
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| 9. |
- Madsen, Thomas, et al.
(author)
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Population size and genetic diversity in sand lizards (Lacerta agilis) and adders (Vipera berus)
- 2000
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In: Biological Conservation. - 1873-2917. ; 94:2, s. 257-262
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Journal article (peer-reviewed)abstract
- Because low genetic diversity may threaten the viability of isolated populations, conservation biologists have devoted much effort to quantify genetic variation. Two techniques routinely used involve levels of mini- and microsatellite polymorphism, with the assumption that levels of variation at these parts of the genome will be reflected in levels of variation at other loci. Our data challenge this assumption. We studied six populations of sand lizards (Lacerta agilis) and five populations of adders (Vipera berus), differing considerably in size and degree of isolation. They, therefore, offer an opportunity to examine how population parameters affect genetic variation at different parts of the genome. Relative population size (based on degree of isolation and number of animals) was not correlated with either minisatellite variability or microsatellite heterozygosity. However, our measures of genetic diversity at the Mhc class I loci of both sand lizards and adders revealed a significant correlation between relative population size and Mhc polymorphism: non-isolated/larger populations exhibited higher genetic diversity than did isolated/small populations. Consequently, only the Mhc-based estimates of genetic diversity yielded results in agreement with population genetic theory. (C) 2000 Elsevier Science Ltd. All rights reserved.
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| 10. |
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