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Tibet University is the largest university in Tibet. It has two campuses: one in Lhasa and one in Nyingchi. Wikipedia.

Caidong C.,University of Bergen | Caidong C.,Tibet University | Sorteberg A.,University of Bergen
Journal of Glaciology | Year: 2010

Due to a lack of in situ measurements, model-based studies of glacier mass balance in the Tibetan Plateau are very limited. An energy-balance model is applied to analyse the mass-balance sensitivity of Xibu glacier, in the Nyainqêntanglha mountain range, to climatic change. A sensitivity calculation shows that a temperature change of ±1°C or a precipitation change of ±35% changes the equilibrium-line altitude (ELA) by 140 ± 125 m. We use a clustering method to link local weather parameters, including wet-season temperatures, to weather types observed over the period 1955-2006. Modelled variability of the Xibu glacier mass balance seems to be controlled by airtemperature variations during the wet season (May-September) and by a long-term warming trend that is unrelated to weather type. The observed wet-season temperature trend of 0.23°C(10a)-1 leads to an estimated lengthening of the ablation season by 8 days at the glacier terminus (5000ma.s.l.) and by 23 days at the ELA (5590ma.s.l.) over the period 1966-2005. The calculated rise in the ELA was 49 m (10 a)-1. Source

Jin J.,Tibet University
International Journal of Earth Sciences and Engineering | Year: 2014

Because many factors will impact cutting slope stability in Alpine region, different distributional conditions of each parameter will exert an influence on cutting slope. Therefore, this paper proposes sensitivity recognition comprehensive assessment system, by aiming at limitation of single indicator for impacting slope stability parameter analysis, considers all kinds of estimation stability comprehensively and avoids from onesidedness of single indicator analysis. Based on highway cutting slope excavation of Nyingchi Prefecture in Tibet, the paper selects typical mechanical model to analyze influences of diversified influencing parameters on cutting slope stability in Alpine region. First of all, the paper adopts dimension analysis method to discriminate variation of cutting slope stability indicator through key dimensionless parameters, so as to obtain key parameter’s incidence on stability. Then, it applies sensibility grey relational analysis method to confirm relevant sequence of each influencing parameter. Ultimately, it inspects sensibility recognition combined system through numerical simulation method. The research shows that sensitivity recognition comprehensive assessment system can confirm cutting slope incidence and relevant sequence’s on each parameter. Therefore, it can provide reliable theoretical foundation on cutting slope stability analysis and construction in Alpine region. © 2014 CAFET-INNOVA TECHNICAL SOCIETY. All rights reserved. Source

Wen J.,Smithsonian Institution | Zhang J.-Q.,Peking University | Nie Z.-L.,CAS Kunming Institute of Botany | Zhong Y.,Tibet University | And 2 more authors.
Frontiers in Genetics | Year: 2014

The Qinghai-Tibetan Plateau (QTP) is the highest and one of the most extensive plateaus in the world. Phylogenetic, phylogeographic, and ecological studies support plant diversifications on the QTP through multiple mechanisms such as allopatric speciation via geographic isolation, climatic oscillations and divergences, pollinator-mediated isolation, diploid hybridization and introgression, and allopolyploidy. These mechanisms have driven spectacular radiations and/or species diversifications in various groups of plants such as Pedicularis L., Saussurea DC., Rhododendron L., Primula L., Meconopsis Vig., Rhodiola L., and many lineages of gymnosperms. Nevertheless, much work is needed toward understanding the evolutionary mechanisms of plant diversifications on the QTP. Well-sampled biogeographic analyses of the QTP plants in the broad framework of the Northern Hemisphere as well as the Southern Hemisphere are still relatively few and should be encouraged in the next decade. This paper reviews recent evidence from phylogenetic and biogeographic studies in plants, in the context of rapid radiations, mechanisms of species diversifications on the QTP, and the biogeographic significance of the QTP in the broader context of both the Northern and Southern Hemisphere biogeography. Integrative multidimensional analyses of phylogeny, morphological innovations, geography, ecology, development, species interactions and diversifications, and geology are needed and should shed insights into the patterns of evolutionary assembly and radiations in this fascinating region. © 2014 Wen, Zhang, Nie, Zhong and Sun. Source

For the sake of discussion to concentrating characteristics of multi dish concentrator, a simple calculation method of layout is given. By comparative study, the key of designing identical multi dish solar concentrator is confocal is deduced. In confocal and suitable f/D ratio conditions the smaller receiving aperture could be ensured, and the compound paraboloid receiver is not necessary. Copyright © 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved. Source

Zhong B.,Fudan University | Zhong B.,Massey University | Yonezawa T.,Fudan University | Zhong Y.,Fudan University | And 3 more authors.
Molecular Biology and Evolution | Year: 2010

The phylogenetic position of Gnetales is one of the most contentious issues in the seed plant systematics. To elucidate the Gnetales position, an improved amino acid substitution matrix was estimated based on 64 chloroplast (cp) genomes and was applied to cp genome data including all three lineages of Gnetales in maximum likelihood analyses of proteins. Although the initial analysis strongly supported the sister relation of Gnetales with Cryptomeria (Cupressophyta or non-Pinaceae conifers) (the "Gnecup" hypothesis), the support seems to be caused by a long-branch attraction (LBA) artifact. Indeed, by removing fastest evolving proteins that are most likely associated with the LBA, the support drastically declined. Furthermore, another analysis of partial genome data with dense taxon sampling of conifers showed that, in psbC, rpl2, and rps7 proteins, there are many parallel amino acid substitutions between the lineages leading to Gnetales and to Cryptomeria, and by further excluding these three genes, the sister relation of Gnetales with Pinaceae (the "Gnepine" hypothesis) became supported. Overall, our analyses indicate that the LBA and parallel substitutions cause a seriously biased inference of phylogenetic position of Gnetales with the cp genome data. © 2010 The Author. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. Source

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