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  • 1.
    Al-Ansari, Nadhir
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Hanbali, Ahmad
    Kojimatchi 4-chome, Chiyoda-ku, Tokyo 102-0083 Japan.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Locating solid waste landfills in Mafraq city, Jordan2012Inngår i: Journal of Advanced Science and Engineering Research, ISSN 2231-8844, Vol. 2, nr 1, s. 40-51Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Protection of the environment from solid waste hazards is becoming a serious problem. Different laws and legislations had been put into practice for this purpose. The effect of solid waste in countries like Jordan with limited financial and natural resources and high population growth rate is more severe. To overcome these difficulties, prudent management system for solid waste is required. Furthermore, solid waste disposal site should be selected using scientific criteria to prevent any harmful effect on local communities and the environment. Criteria for solid waste disposal dump site for Mafraq city were selected in accordance with well known international requirements that suit the local conditions. These criteria were used to select the best suitable solid waste dump site using remote sensing and geographic information system techniques. The selected sites are harmless to human life, natural resources and the environment.

    Fulltekst (pdf)
    fulltext
  • 2.
    Al-Ansari, Nadhir
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Ezz-Aldeen, Mohammad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Application of swat model to estimate the sediment load from the left bank of Mosul dam2013Inngår i: Journal of Advanced Science and Engineering Research, ISSN 2231-8844, Vol. 3, nr 1, s. 47-61Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Mosul dam is the biggest dam in Iraq on Tigris River. It is a multipurpose dam with a designed storage capacity of 11.11*109 m3. The Soil and Water Assessment Tool (SWAT) working with Geographical Information System (GIS) was applied to simulate the daily runoff and sediment yield from the seven valleys entering the reservoir from the left side. The model was applied for the period 1988-2008 based on daily climatic data of Mosul city and Mosul Dam Stations. The results indicated that the average yearly water flow was 13.8 *106 m3. It varies with time and among the valleys depending on the soil type, land watershed topography, watershed area in addition the other effective factors, and rainfall depth of that year. The resultant average annual sediment yield was 702*106 ton from these valleys. The sediment yield from each valley depends on runoff coefficient of the valley, soil type and plant cover. These factors affect soil detachment and rainfall properties (depth and intensity) that in turn affect rainfall detachment force. The total sediment yield for the considered period was 14753*103 ton. This represent about 0.42% of the dead storage of the reservoir (2.9*109m3) which is about 0.11% of the total reservoir storage capacity.

    Fulltekst (pdf)
    FULLTEXT01
  • 3.
    Al-Ansari, Nadhir
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Almuqdadi, Kadhim
    Arab Academy-Denmark.
    Engineering solution for Radioactive Waste in IRAQ2014Inngår i: Journal of Advanced Science and Engineering Research, ISSN 2231-8844, Vol. 4, nr 1, s. 18-36Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Depleted uranium (DU) is a by-product of the enrichment of natural uranium for nuclear reactor-grade or nuclear weapons-grade uranium. DU is chemically identical to natural uranium. Depleted uranium is chemically identical to natural uranium. DU is depleted with isotope of U235 and its radioactivity is 60% of the natural uranium and increases to 80% after few months and is usually considered as low level radioactive waste (LLW).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).During the second Gulf war in 2003 U.S. and British troops have reportedly used more than five times as many DU bombs and shells as the total number used during the 1991 war for the invasion and occupation of Iraq. It was estimated that more than 1100 to 2200 tons of DU was used. As a consequence the ruminants of wars are affecting the people (30 million) and environment. There are hundreds of sites contaminated with nuclear radiation.There is no Iraqi strategy and/or national program, not even well thought out plans and scientific personnel and technical equipment required to clean Iraq of these wastes. The aim of this work is to high light the environmental implications of the two Gulf wars on Iraq and suggest possible solutions to the problem.

    Fulltekst (pdf)
    FULLTEXT01
  • 4.
    Hatem, Mohammed
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Al-Ansari, Nadhir
    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.
    Jonasson, Jan-Erik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Rheological properties of low pH cement-palygorskite injection grout2013Inngår i: Journal of Advanced Science and Engineering Research, ISSN 2231-8844, Vol. 3, nr 3, s. 167-192Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The rheological properties of cementitious materials containing fine particles, such as mineral admixture were investigated using a Viso Star-L rheometer with cylindrical spindles. Selected features of the behavior of these materials are evaluated from a rheological perspective through literatures results for the past 30 years. One of the important factors that governs the ability of grout to penetrate fractures, channels and porous material is the rheology. The mineral admixture was clay palygorskite which can be used for early gelation because of its thixotropic properties as well as the powder quartz used as aggregate. The cementitious materials were designed and three recipes (MPG1, MPG2 and MPG3) were examined in this research by changing the mix proportions of the mineral admixture palygorskite and water content. For ensuring the accuracy of rheological measurement for the candidate’s grouts, necessary verification was been evaluated such as, influence of mixing time, stability and “time effect” to the accuracy of viscosity measurement, and yield stress as well as the physical properties at 3, 7 and 28 days. The results showed that grouts recipes with quartzite aggregate of different granulometry, are chemically compatible and fulfill the requirement of containing no organic matter. Candidate’s grouts found to satisfy the stable sedimentation criteria with sedimentation rates less than 5% after 2 hours. Furthermore, it was found that the grout recipe 3 followed by 1 showed lower yield stress and plastic viscosity which are (0.1 Pa and 0.269 Pas) and (0.288 Pa and 0.531 Pas) respectively.

    Fulltekst (pdf)
    FULLTEXT01
  • 5.
    Hatem, Mohammed
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Gburi, Majid
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Jonasson, Jan-Erik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Design of concrete mixes by systematic steps and ANN2012Inngår i: Journal of Advanced Science and Engineering Research, ISSN 2231-8844, Vol. 2, nr 4, s. 232-251Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The current research caters for the possibility of arriving at a system for designing concrete mixeseasily using available materials locally by specified wide ranges of pre-requisites of three mainprescribed properties to cover a good variety of practical mixes, which are water, water-cement ratioand total aggregate-cement ratio. Using these three properties, a tri-linear form was constructed bygraphical technique manner based on absolute volume approach. This approach defines as asummation of absolute volume for each of these three materials individually water, cement andaggregate should be equal to the absolute volume of whole concrete mixture based on thesealtogether. A quad-form area which includes a wide range of mixes can be formed from thisrepresentation. This area should achieve all the prescribed properties aforementioned. Artificial neuralnetwork concept used in this study also to build easily and quickly system which can be translatedinto Excel sheet. This system predict proportions of concrete mixture and the compressive strengthusing the results designed by the quad-form area method in addition to the data from literature around500 mixes based on local materials used in Iraq. Six input parameters (water to cement ratio, theslump, % of fine to total aggregate content, maximum aggregate size, fineness modulus of fineaggregate and the compressive strength) were used in this system to get the outputs. In addition, nineinput parameters ((water, cement, sand and gravel contents) and the properties of the mix (Finenessmodulus, W/C ratio, the slump, % of fine to total aggregate and the M.A.S)) were used as basis ofcompressive strength model. The algorithm of this system aimed to reduce the high number of trailmixes error as well as saving the labors, cost and time. Results indicated that the concrete mix designand the compressive strength model can be predicted accurately by using graphical perspective andthe ANN approach.

    Fulltekst (pdf)
    FULLTEXT01
  • 6.
    Hatem, Mohammed
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    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.
    Optimization of concrete by minimizing void volume in aggregate mixture system2012Inngår i: Journal of Advanced Science and Engineering Research, ISSN 2231-8844, Vol. 2, nr 3, s. 208-222Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The behavior of concrete is affected by the size, distribution of the voids, the porosity and of the granulometry of the aggregate mixture. As a consequence it necessary for engineers to consider in detail particle packing concepts and their influence on the physical performance of concrete. The present study included determination of the fineness modulus, cement paste volume based on slump test and the properties of fresh and hardened concrete. It also comprised a study of the applicability of two theoretical models Toufar’s and 4C-packing program for selecting suitable relative amounts of the concrete constituents, for obtaining a minimum void ratio. Comparison of the results was made from using these theoretical models literature-derived experimental data. The models gave similar results and suggest similar combinations of materials to give minimum void ratio. Optimization of the composition of the aggregate material in concrete is beneficial with respect to economy (low cement content), strength and durability. It was noted that minimizing the void ratio (V) tends to raise the stiffness and that the compressive strength (푓푐′) is closely related also to their molding (R) and fineness modules (FM). It was found that the compressive strength can be predicted by applying the formula;푓푐′=−2.1−63.8 푉+0.150 푅+10.4 퐹푀; R2=0.94, and two other relationships related to slump data and cement content.

    Fulltekst (pdf)
    FULLTEXT01
  • 7.
    Huang, Yi
    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.
    Jia, Qi
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    The one dimensional model for coarse particle around mining area in northern Sweden2012Inngår i: Journal of Advanced Science and Engineering Research, ISSN 2231-8844, Vol. 2, nr 2, s. 126-137Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Computational model had been established to predict the coarse dust transport rate within the Malmberget mining area in northern Sweden. Matlab GUI designing had been introduced to enhance the computation process. Certain modification methods were developed in order to improve the accuracy of the model. Dust retention time was calculated to estimate the dust transport in the suspension form. Field calibration proves the code works fairly well for the coarse dust in the research area.

    Fulltekst (pdf)
    FULLTEXT01
  • 8.
    Issa, Issa E.
    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.
    Changes in bed morphology of Mosul dam reservoir2013Inngår i: Journal of Advanced Science and Engineering Research, ISSN 2231-8844, Vol. 3, nr 2, s. 86-95Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Mosul dam is one of the biggest hydraulic structures in Iraq. It was constructed on the Tigris River in the north of Iraq for multiple purposes: irrigation, flood control and power generation. The initial storage capacity and water surface area of its reservoir reach 11.11 km3 and 380 km2 respectively at the maximum operation level 330 m.a.s.l. The dam was operated in 1986. Since that time no survey has been conducted to determining the characteristics of sedimentation in the reservoir. Blockage of the intakes of the pump station for North Al-Jazira Irrigation Project in Mosul dam reservoir has highlighted the importance of sedimentation problems within the reservoir.Sediment distribution was studied within the reservoir. A comparison was made between the conditions at the start of the dam operation and a recent bathymetric survey conducted in 2011.The former was achieved using a topographic map scale 1: 50000 dated 1983 which was converted to a triangular irregular network (TIN) format using the Arc/GIS program. The results of the bathymetric survey were also converted to the TIN map format using the above program. Comparison of the two maps shows that the sedimentation magnitude in the upper zone of the reservoir, where the River Tigris enters, was highest and gradually reduced toward Mosul dam site. Maximum deposition thickness within the reservoir was 17.6 m. The thalweg bed slope of the River Tigris within reservoir area changed from 0.65 m.km-1 before dam construction to 0.71 m.km-1 on the 2011 survey. Zones within the

    Fulltekst (pdf)
    FULLTEXT01
  • 9.
    Rodriguez, Juan M.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Edeskär, Tommy
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Case of study on particle shape and friction angle on tailings2013Inngår i: Journal of Advanced Science and Engineering Research, ISSN 2231-8844, Vol. 3, nr 4, s. 373-387Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Tailings are crushed and milled materials result of the mining production. Tailings need to be stored in facilities, usually tailings dams, for a long time period for mainly safety and environmental protection. In order to design tailings dams in a long term perspective not only current material properties is needed but also future changes of these properties due to e.g. weathering. On a particle level the weathering will result in shape changes and decomposition. By studying the changes in shape a prognosis of changes in properties of a tailings deposit may be established.Tailings are site specific material and are not well investigated compared to natural geological materials such as soil. Tailings materials size ranges generaly from sand to silt and the particle shape by genesis or production processes. Based on laboratory tests tailings from the Aitik mine has been investigated through triaxial tests and particle shape quantification by two dimensions image analysis. The shape descriptors Aspect Ratio, Circularity, Roundness and Solidity are used in this study. These shape descriptors are evaluated based on how well these describes talings materials. The evaluated shape descriptors are used in previous published empirical relations between shape and friction angle. As reference are friction angles evaluated by triaxial tests on the material used.The results show that the particle shape is affected by the size of the aggregates. Aggregates in small fractions are more elongated and less rounded, i. e. more angular, compared to larger. Furthermore, the Aspect Ratio and Circularity seems to be the most situable quantities to describe the tailings behaviour in relation with the empirical model. The accuracy in predicting the friction angle of the tailings by previously published relations based on uniformly graded sand material are low. But the systematic underestimation of the friction angle indicates that it would be possible to establish such empirical relations based on tailings material.

    Fulltekst (pdf)
    FULLTEXT01
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