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  • 1. Alanbari, Mohammad
    et al.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Jasim, Hadeel
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Modeling landfill suitability based on GIS and multicriteria decision analysis: case study in Al-Mahaweel Qadaa2014Inngår i: Natural Science, ISSN 2150-4091, E-ISSN 2150-4105, Vol. 6, nr 11, s. 828-851Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Waste management system is not regulated in Iraq. At present, there are various techniques used for solid waste management such as landfill, thermal treatment, biological treatment, recycling etc. Landfill is the most common mode for the disposal of solid waste. However, landfill site selection is quite complex process and it depends on several criteria and regulations. In this study landfill site selection is performed for Al-Mahaweel qadaa using Multicriteria Decision Analysis (MCDA) And Geographic Information System (GIS). It should be mentioned however, that the existing landfill in this area, is temporary and does not fulfill the environmental conditions. To select suitable landfill site, several criteria were considered such as Urban centers, Land use, Airports, Pipes, Power lines, Railways, Roads, slope, streams, Surface water, Industrial areas, Oil pipes, Liquid gas pipes, Soil types are prepared. (MCDA) was used to evaluate the relative importance of each criterion. Each map layers were formed with the aid of GIS and final suitability map was created by overlay analyses of each criterion map. According to obtained results, high and low suitable areas were determined in the study area. Field and office checks were performed out to determine the accuracy and suitability of the candidate sites.

  • 2.
    Alanbari, Mohammad Ali
    et al.
    Babylon University.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Jasim, Hadeel Kareem
    Babylon University.
    GIS and Multicriteria Decision Analysis for Landfill Site Selection in AL-HashimyahQadaa2014Inngår i: Natural Science, ISSN 2150-4091, E-ISSN 2150-4105, Vol. 6, nr 5, s. 282-304Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Waste management system is not well regulated in Iraq. Despite the fact that there are various techniques used for solid waste disposal, landfill is the most common mode for the disposal of solid waste in Iraq, landfill site selection criteria is quite complex process and it depends on several regulation and factors. In this study landfill site selection is performed by using Multicriteria Decision Analysis (MCDA) and Geographic Information System (GIS) for the Al-Hashimyahqadaa. Existing landfills in qadaa are temporary and/or non-conforming to the environmental conditions. In order to determine landfill site, several criteria were examined such as Urban centers, Land use, Airports, Pipes, Power lines, Railways, Roads, Slope, Streams, Surface water, Industrial areas, Oil pipes, Liquid gas pipes, Soil types are prepared. MCDA was used to measure the relative importance weighting for each criterion. Each map layer was prepared using GIS and the final suitable map was created by overlay analyses of each criterion maps. According to the results, high and low suitable areas were determined in the study area. Field site check was performed to determine the accuracy and suitability of the candidate sites.

  • 3.
    Al-Ansari, Nadhir
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Oun, Salem
    Al al-Bayt University.
    Hadad, Wafa
    Al al-Bayt University.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Water loss in Mafraq governorate, Jordan2013Inngår i: Natural Science, ISSN 2150-4091, E-ISSN 2150-4105, Vol. 5, nr 3, s. 333-340Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Jordan is located in the Middle East and covers an area of 89,342 km2. The total population of Jordan is 6,508,271. Jordan is rapidly facing a severe water supply crisis due to greater demands on a finite quantity of available water. If current trends continue, it has been estimated that the country will experience a chronic water shortage by 2020. Despite these shortages, water loss in the distribution network is relatively high where it reaches 46%. Mafraq Governorate has the maximum water loss. Continuous records and data for the period 1999-2004 for Mafraq water authority were investigated for the water supply and lose. Water losses were evaluated, and suggestions were given to minimize the loss.

  • 4.
    Al-Ansari, Nadhir
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Suggested landfill sites for hazardous waste in Iraq2013Inngår i: Natural Science, ISSN 2150-4091, E-ISSN 2150-4105, Vol. 5, nr 4, s. 463-477Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Iraq experienced two devastating wars in 1991 and 2003, during which massive amounts of new weapons and sophisticated manufactured nuclear weapons were used called Depleted Uranium (DU). As a consequence of the radioactive contamination; the humans are suffering from various disease like cancer and the environment is polluted.In practice, there is no strategy and/or national program, not even well thought out plans and scientific personnel and technical equipment required to clean Iraq of these wastes. Reviewing the geological, topographical and hydrological data, it had been noticed that Umm Chaimin depression is a good candidate site to dump all contaminated radioactive scrap and soil. The suggested design of the landfill will ensure safe containment of the waste for hundreds of thousands of years even if significant climatic changes will take place.

  • 5.
    Andersson-Sköld, Yvonne
    et al.
    Statens geotekniska institut.
    Falemo, Stefan
    Statens geotekniska institut.
    Tremblay, Marius
    Statens geotekniska institut.
    Development of methodology for quantitative landslide risk assessment - Example Göta river valley2014Inngår i: Natural Science, ISSN 2150-4091, E-ISSN 2150-4105, Vol. 6, nr 3, s. 130-143Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Effective landslide risk management requires knowledge of the landslide risks. This paper presents a risk assessment methodology for semi-regional scale. The landslide probability is assessed taking into account expected climate change in the case study area (the Göta river valley). Climate change is expected to result in increased erosion and water fluctuations. There are large areas with marine clays, often quick clay, in the area and the landslide process can be rapid with extensive damages and casualties. The consequence methodology includes a wide range of consequences assessed by monetary valuation. The consequences and the landslide probability are combined as pairs of values in a risk matrix and the risk is also presented on a map. The map has been used as discussion and decision bases in the municipalities in the Göta river valley, in the county administration and on governmental level to estimate the needs of risk mitigation and to make priorities.

  • 6.
    Jia, Qi
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Estimation of road dust using BSNEs2013Inngår i: Natural Science, ISSN 2150-4091, E-ISSN 2150-4105, Vol. 5, nr 5, s. 567-572Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Mining is a core industry in Sweden and plays an important role in the economic development of the country. Though the importance of mining dust has been well recognized, the quantification of dust production with regard to individual source activity has rarely been done in Sweden. Depending on the type of source activity, dust estimation method can be chosen from three alternatives: exposure profiling methods, back calculation method, and wind erosion prediction method. Also included in the paper is an example of experiment, which was executed on two unpaved roads in Lulea, Sweden by using exposure profiling method. The experiment concluded that dust emission due to vehicle transportation is strongly dependent on traveling speed and road bed material.

  • 7.
    Pusch, Roland
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Taie, Laith
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hatem, Mohammed
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Optimal ways of disposal of highly radioactive waste2012Inngår i: Natural Science, ISSN 2150-4091, E-ISSN 2150-4105, Vol. 4, nr 11A, s. 906-918Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Multibarrier concepts are commonly proposed for effective isolation of highly radioactive waste (HLW). Present concepts consider the host rock as a barrier by retarding migration of possibly released radionuclides to the biosphere, containers for preventing release of radionuclides, and “buffer clay” embedding the canisters for providing ductility and minimizing the risk of container breakage and for delaying migration of possibly escaping radionuclides. Closer analysis of the isolating functions shows that rock will only serve as a mechanical protection of the “nearfield”, the containers of proposed types can be short-lived, and the surrounding clay will be increasingly permeable and stiffen hence becoming less ductile with time. A different approach, representing an alternative to the common concepts, can be safer and cheaper. It takes the HIPOW copper canister as the only major barrier and a cheap but sufficiently efficient buffer as embedment. The repository can consist of an abandoned copper mine, an option being to place HLW in emptied drifts while mining is still going in not yet exploited parts of the ore body.

  • 8.
    Pusch, Roland
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Ramqvist, Gunnar
    El-Tekno AB.
    Hatem, Mohammed
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pourbakhtiar, Alireza
    Can sealing of rock hosting a repository for highly radioactive waste be relied on?2012Inngår i: Natural Science, ISSN 2150-4091, E-ISSN 2150-4105, Vol. 4, nr 11A, s. 895-905Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Multibarrier systems are commonly proposed for effective isolation of highly radioactive waste (HLW). Presently considered concepts take the host rock as a barrier claiming it to retard migration of possibly released radionuclides from HLW containers to the biosphere. This capacity is small unless water-bearing fracture zones intersecting the blasted waste-containing tunnels and excavation-disturbance zones around them can be sealed by grouting and construction of bulkheads, but this is effective only for a very limited period of time as explained in the paper. The disturbed zones thence make the entire repository serve as a continuous hydraulic conductor causing quick transport of released radionuclides up to the biosphere. The dilemma can be solved by accepting the short-circuiting function of the disturbed zones along the tunnels on the condition that totally tight waste containers be used. Deep holes bored in the site selection phase through the forthcoming repository can be effective pathways for radionuclides unless they are properly sealed. They are small-scale equivalents of tunnels but do not have any ex-cavation damage and can be effectively sealed by using clay and concrete of new types. Applying this principle to very deep boreholes with a diameter of a few decimeters would make it possible to safely store slim, tight HLW canisters for any period of time.

  • 9. Sissakian, Varoujan
    et al.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Origin of some Transversal Linear Features of NE- SW Trend in Iraq, and their Geological Characters2014Inngår i: Natural Science, ISSN 2150-4091, E-ISSN 2150-4105, Vol. 6, nr 12, s. 996-1011Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Iraq is located at the extreme northeastern part of the Arabian Plate, which is in collision with the Eurasian Plate. This collision is still onward; and has caused alignment of the evolved structures in NW – SE trend; mainly, especially in the northern, northeastern and eastern sides of Iraq. However, many transversal linear features of NE – SW trend, represented by rivers, streams, valleys, playas, anticlines and offsets are developed; in parallel trend to the main compressional forces created by the aforementioned collision. Many examples from different parts of Iraq confirm the mechanism of their formation through the geological, geomorphological, tectonics and structural aspects. Although the existing linear features are tens of kilometers in length, but almost no surface displacements were reported, except very few, in some parts of Iraq. The given examples are selected to be the most obvious, when geophysical data are available, the surface and subsurface geology of the involved area is correlated to deduce whether the surface expression coincides with the subsurface or otherwise. A brief tectonic history is also given.

  • 10.
    Tarvainen, Matti
    et al.
    Helsinki University.
    Valtonen, Outi
    Helsinki University.
    Husebye, Eystein
    BCCS, Uni Research Bergen.
    Lund, Björn
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Geofysik.
    Seismic analysis of aircraft accidents2013Inngår i: Natural Science, ISSN 2150-4091, E-ISSN 2150-4105, Vol. 5, nr 7, s. 811-817Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Seismic records from Finnish and Swedish sta- tions were analyzed for a study of two aircraft accidents in Finland and Sweden. A Hornet F-18 fighter crashed in central Finland, and analysis of recorded impact signals from 7 nearby seis- mic stations yielded in a crash location only 4 km in error. An estimated magnitude (ML) of 0.5 units gave an impact velocity of 335 m/sec (1200 km/h), which was in excellent agreement with that reported by the Finnish Air Force. A Norwegian Hercules transport plane crashed in foul weather near the summit of Mt. Kebnekaise, NW Sweden. Both seismic and infrasound signals were weak, and in our interpretation, this implied that the Hercules aircraft had a less steep impact angle against the mountain. We also examined seismic analyses of other spectacular air accidents like that of Lockerbie, UK in 1988, and terrorist air- craft attacks on September 11th, 2001 in the USA. Likewise, accidents at sea, such as the sinking of the Russian submarine Kursk in the Barents sea in 2000, and the freighter M/S Rocknes near Bergen in 2004, were recorded and analyzed seismically. In this study, we demonstrated that it was feasible to use seismic registrations to locate impact sites, and to define the exact time of such accidents. Also, negative evidence, i.e., lack of seismic recordings, may provide some information of such accidents and their conse-quences.

  • 11.
    Åkerstedt, Hans O.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Strömningslära och experimentell mekanik.
    Deposition of charged nano-particles in the human airways including effects from cartilaginous rings2011Inngår i: Natural Science, ISSN 2150-4091, E-ISSN 2150-4105, Vol. 3, nr 10, s. 885-888Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper presents a numerical study of the deposition of spherical charged nano-particles caused by convection, Brownian diffusion and electrostatics in a pipe with a cartilaginous ring structure. The model describes the deposition of charged particles in the different generations of the tracheobronchial tree of the human lung. The upper airways are characterized by a certain wall structure called cartilaginous rings which modify the particle deposition when compared to an airway with a smooth wall. The problem is defined by solving Naver-Stokes equations in combination with a convective-diffusion equation and Gauss law for electrostatics. Three non- dimensional parameters describe the problem, the Peclet number Pe = 2ūa/D , the Reynolds number Re = ūa/v and an electrostatic parameter α=α2c0q2/(4ε0κT) . Here U is the mean velocity, a the pipe radius and D the diffusion coefficient due to Brownian motion given by D=κTCu/3πμd , where Cu is the Cunningham-factor Cu=1+λ/d(2.34+1.05exp(-0.39d/λ)) Here d is the particle diameter and λ the mean free path of the air molecules. Results are provided for generations G4-G16 of the human airways. The electrostatic parameter is varied to model different concentrations and charge numbers

  • 12.
    Åkerstedt, Hans O.
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Strömningslära och experimentell mekanik.
    Högberg, Sofie
    Lundström, Staffan
    Sandström, Tomas
    Umeå universitet.
    The effect of cartilaginous rings on particle deposition by convection and Brownian diffusion2010Inngår i: Natural Science, ISSN 2150-4091, E-ISSN 2150-4105, Vol. 2, nr 7, s. 769-779Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A finite volume method for the numerical solution of viscoelastic flows is given. The flow of a differential upper-convected Maxwell (UCM) fluid through a contraction channel has been chosen as a prototype example. The conservation and constitutive equations are solved using the finite volume method (FVM) in a staggered grid with an upwind scheme for the viscoelastic stresses and a hybrid scheme for the velocities. An enhanced-in-speed pressure-correction algorithm is used and a method for handling the source term in the momentum equations is employed. Improved accuracy is achieved by a special discretization of the boundary conditions. Stable solutions are obtained for higher Weissenberg number (We), further extending the range of simulations with the FVM. Numerical results show the viscoelasticity of polymer solutions is the main factor influencing the sweep efficiency.

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