Possible Concepts for Waterproofing of Norwegian TBM Railway Tunnels   总被引：1，自引：0，他引：1  

Øyvind Dammyr  Bjørn Nilsen  Kurosch Thuro  Jørn Grøndal 《Rock Mechanics and Rock Engineering》2014,47(3):985-1002

The aim of this paper is to evaluate and compare the durability, life expectancy and maintenance needs of traditional Norwegian waterproofing concepts to the generally more rigid waterproofing concepts seen in other European countries. The focus will be on solutions for future Norwegian tunnel boring machine railway tunnels. Experiences from operation of newer and older tunnels with different waterproofing concepts have been gathered and analyzed. In the light of functional requirements for Norwegian rail tunnels, some preliminary conclusions about suitable concepts are drawn. Norwegian concepts such as polyethylene panels and lightweight concrete segments with membrane are ruled out. European concepts involving double shell draining systems (inner shell of cast concrete with membrane) and single shell undrained systems (waterproof concrete segments) are generally evaluated as favorable. Sprayable membranes and waterproof/insulating shotcrete are welcomed innovations, but more research is needed to verify their reliability and cost effectiveness compared to the typical European concepts. Increasing traffic and reliance on public transport systems in Norway result in high demand for durable and cost effective solutions.  相似文献   

Accumulation of Copper and Zinc in Danish Agricultural Soils in Intensive Pig Production Areas     

Ilse Gräber  Jørgen F. Hansen  Svend E. Olesen  Jens Petersen  Hans S. Østergaard  Lars Krogh 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(2):15-22

Geografisk Tidsskrift, Danish Journal of Geography 105(2):15–22, 2005

The change of Cu and Zn concentrations in Danish agricultural soils was studied in areas with intensive pig production. Cu and Zn are found in pig manure as the metals are added to pig feed as growth promoters. The changes in concentrations of total and 0.02 MEDTA extractable Cu and Zn in soils from 1986 to 1998 were determined from samples taken at two depths (0–25 cm and 25–50 cm) from 73 sites. Pig manure and mineral fertilizer was added to 60 sites whereas fertilizer only was used on 13 sites. During the survey period soil Cu concentrations increased in both depths but mostly in the sites where pig manure was added. Furthermore, the results indicated that some plant-available Cu and Zn were transported from the topsoil to the subsoil. No significant change in soil Zn concentration was found although a slight reduction was observed. Comparing soil metal concentrations observed in 1998 to the total pig manure application in a 12-year period, it was observed that application of manure caused an accumulation of Cu and of Zn in the upper 50 cm soil. The accumulation rates correspond to the Cu and Zn concentrations in the pig manure.  相似文献   

Erratum: Late glacial and holocene 10Be production rates for western Norway     

Brent M. Goehring  Øystein Strand Lohne  Jan Mangerud  John Inge Svendsen  Richard Gyllencreutz  Joerg Schaefer  Robert Finkel 《第四纪科学杂志》2012,27(5):544-544

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Fishing‐induced evolution of growth: concepts,mechanisms and the empirical evidence     

Katja Enberg  Christian Jørgensen  Erin S. Dunlop  Øystein Varpe  David S. Boukal  Loïc Baulier  Sigrunn Eliassen  Mikko Heino 《Marine Ecology》2012,33(1):1-25

The interest in fishing‐induced life‐history evolution has been growing in the last decade, in part because of the increasing number of studies suggesting evolutionary changes in life‐history traits, and the potential ecological and economic consequences these changes may have. Among the traits that could evolve in response to fishing, growth has lately received attention. However, critical reading of the literature on growth evolution in fish reveals conceptual confusion about the nature of ‘growth’ itself as an evolving trait, and about the different ways fishing can affect growth and size‐at‐age of fish, both on ecological and on evolutionary time‐scales. It is important to separate the advantages of being big and the costs of growing to a large size, particularly when studying life‐history evolution. In this review, we explore the selection pressures on growth and the resultant evolution of growth from a mechanistic viewpoint. We define important concepts and outline the processes that must be accounted for before observed phenotypic changes can be ascribed to growth evolution. When listing traits that could be traded‐off with growth rate, we group the mechanisms into those affecting resource acquisition and those governing resource allocation. We summarize potential effects of fishing on traits related to growth and discuss methods for detecting evolution of growth. We also challenge the prevailing expectation that fishing‐induced evolution should always lead to slower growth.  相似文献   

Numerical studies of large-amplitude internal waves shoaling and breaking at shelf slopes     

Øyvind Thiem  Jarle Berntsen 《Ocean Dynamics》2009,59(6):937-952

Hydro carbon fields beyond the shelf break are presently being explored and developed, which has increased the scientific focus in this area. Measurements from the slopes reveal large variability in temperature and velocity, and some of the observed events are due to interactions between large-amplitude oscillations of the thermocline and the topography. The present study focuses on the strong currents that are generated near the seabed during shoaling and breaking of internal waves along shelf slopes. The parameter regime used is similar to the one for the Nordic Seas. The results show that, during shoaling of large internal waves along (gentle) slopes, the energy is transferred towards smaller scales and strong velocities (over 1 m s^− 1) can be generated. To resolve all scales involved is still not feasible, and therefore, the model results are sensitive to the grid size and the subgrid scale closure.  相似文献   

The international workshop on wave hindcasting and forecasting and the coastal hazards symposium   总被引：1，自引：1，他引：0  

Øyvind Breivik  Val Swail  Alexander V. Babanin  Kevin Horsburgh 《Ocean Dynamics》2015,65(5):761-771

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The heat goes on—changes in indices of hot extremes in Poland     

Graczyk  Dariusz  Pińskwar  Iwona  Kundzewicz  Zbigniew W.  Hov  Øystein  Førland  Eirik J.  Szwed  Małgorzata  Choryński  Adam 《Theoretical and Applied Climatology》2017,129(1-2):459-471

Theoretical and Applied Climatology - On the basis of temperature observations at 60 meteorological stations in Poland, changes in the indices associated with the presence of extremely high air...  相似文献   

Changes in low and high flows in the Vistula and the Odra basins: Model projections in the European‐scale context          下载免费PDF全文

Mikołaj Piniewski  Mateusz Szcześniak  Zbigniew W. Kundzewicz  Abdelkader Mezghani  Øystein Hov 《水文研究》2017,31(12):2210-2225

A number of extensive droughts and destructive floods have occurred in Poland in the last 25 years; hence, projections of low and high river flows are of considerable interest and importance. In the first part of this paper, projections of low and high flows in the rivers of the Vistula and the Odra basins (VOB region), for two future time horizons, are presented. Projections are based on the Soil and Water Assessment Tool (SWAT) hydrological model simulations driven by results of the EURO‐CORDEX experiment under Representative Concentration Pathways 4.5 and 8.5. The VOB region covers most of Poland and parts of five neighboring countries, giving this study an international relevance. In the second part of the paper, a review of projections of low and high flows in rivers in Central and Eastern Europe is presented. Despite a substantial spread of flow projections, the main message of the modelling part is that increases of both low and high flows are dominating. The magnitude of increase of low flow is considerably higher than that of high flow. In other words, future streamflow droughts are projected to be less severe, whereas, in contrast, river floods are projected to increase, which is a challenge for flood risk reduction, water management, and climate change adaptation. There is an overall agreement of our findings for the VOB region with projections of hydrological extremes from large‐scale models forced by EURO‐CORDEX results in the European‐scale studies.  相似文献   

The Ritland impact structure,southwestern Norway     

F. RIIS  E. KALLESON  H. DYPVIK  S. O. KRØGLI  O. NILSEN 《Meteoritics & planetary science》2011,46(5):748-761

Abstract– The Ritland structure is a newly discovered impact structure, which is located in southwestern Norway. The structure is the remnant of a simple crater 2.5 km in diameter and 350 m deep, which was excavated in Precambrian gneissic rocks. The crater was filled by sediments in Cambrian times and covered by thrust nappes of the Caledonian orogen in the Silurian–Devonian. Several succeeding events of uplift, erosion, and finally the Pleistocene glaciations, disclosed this well‐preserved structure. The erosion has exposed brecciated rocks of the original crater floor overlain by a thin layer of melt‐bearing rocks and postimpact crater‐filling breccias, sandstones, and shales. Quartz grains with planar deformation features occur frequently within the melt‐bearing unit, confirming the impact origin of the structure. The good exposures of infilling sediments have allowed a detailed reconstruction of the original crater morphology and its infilling history based on geological field mapping.  相似文献   

Pulsation stability of helium-rich subdwarf B stars     

A. Ahmad  C.S. Jeffery  J.-E. Solheim  R. Østensen 《Astrophysics and Space Science》2004,291(3-4):435-439

We present results of the pulsation monitoring of helium-rich subdwarf B (He-sdB) stars using high-speed differential photometry observations made with the SAAO (1.0m), NOT (2.6m) and the IAC80 (0.8m) telescopes. Although we did not find a pulsator in our sample of He-sdB stars, some of the stars show hints of pulsations which need further investigation.  相似文献