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  • 1.
    Adamo, Nasrat
    et al.
    Consultant Engineer, Norrköping, Sweden.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Sissakian, Varoujan
    Chief Researcehr, Department of Petroleum Engineering, Komar University of Science and Technology, Sulaimaniyah, KRG, Iraq.
    Climate Change and the Need for Future Research2022In: Water Resources in Iraq: Perspectives and Prognosis (ICWRPP 2022), Institute of Physics (IOP), 2022, article id 012029Conference paper (Refereed)
    Abstract [en]

    Climate Changes have impacted our planet since the beginning of time. These were manifested by cyclic Ice Ages and Warm Periods ever since. The changes were caused by natural forcing such as, continental drift, plate tectonics, major volcanic eruptions, and internal dynamics of earth and oceans interactions with the atmosphere. The present warm period, the “Holocene Epoch”, is not different from other such periods except for the sharp global warming which began at the onset of the industrial revolution. This was proven by scientific research to be due to anthropogenic drives, i.e., increased fossil fuel burning and increased Co2 and other Green House Gases (GHG) emissions into the atmosphere. These gases trap the sun radiation reflected from earth surface and result in higher earth temperature. The steep rate of rise in temperature trend since 1960s is directly linked to the use of much more fossil fuels in power production and transportation. This has led to more research to quantify the changes and their impacts on the environment and humans. This paper gives a brief history of the scientific research carried out hitherto and policy suggestions made so far to combat the negative impacts of the increasing global warming of the world. Needed future scientific research in this field is outlined, while at the same time suggesting the needs of Iraq of such research. This includes among other things, forming a regional scientific panel for the Middle East countries (ME. IPCC) for carrying out research on regional level, fostering research on national level, encouraging academics for climate change-oriented research and providing the necessary funds and facilities for such research.

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  • 2.
    Ahmadlou, Mohammad
    et al.
    GIS Department, Geodesy and Geomatics Faculty, K.N. Toosi University of Technology, Tehran, Iran.
    Karimi, Mohammad
    GIS Department, Geodesy and Geomatics Faculty, K.N. Toosi University of Technology, Tehran, Iran.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    The use of maximum entropy and ecological niche factor analysis to decrease uncertainties in samples for urban gain models2023In: GIScience & Remote Sensing, ISSN 1548-1603, E-ISSN 1943-7226, Vol. 60, no 1, article id 2222980Article in journal (Refereed)
    Abstract [en]

    Uncertainty is a common problem in spatial modeling and geographical information systems (GIS). Furthermore, urban gain modeling (UGM) contains various dimensions and components of uncertainties. Data sampling is important in UGM, and may cause the results of the models to contain many uncertainties as well as affects their precision and accuracy. A poorly sampled or biased dataset can lead to inaccurate predictions and decreased performance of the models. This paper aims to present and develop novel strategies for sampling and building training datasets that can enhance the performance of data-driven models. In other words, the present study used maximum entropy (ME) and ecological niche factor analysis (ENFA) models to select pure non-change samples with minimal uncertainty for training datasets in UGM of Isfahan and Tabriz cities in Iran. The urban gain of two time intervals of 1992–2002 and 2002–2012 were used for Tabriz City and two time intervals of 1994–2004 and 2004–2014 for Isfahan City. Nine and 14 urban gain drivers were used in the UGM of Isfahan and Tabriz cities, respectively. After the ME and ENFA models produced a training dataset with change and non-change samples with the lowest uncertainty, three well-known models, namely random forest (RF), artificial neural network (ANN), and support vector machine (SVM) were used for the modeling. Moreover, the ME and ENFA models that were used to investigate the uncertainty of the sampling procedure were used as the one-class prediction models. Compared to extant studies, the proposed ME – based sampling strategy increased the area under the receiver operating characteristic curve (AUROC), figure of merit, producer’s accuracy, and overall accuracy by 5.5%, 5%, 5%, and 3%, respectively, in the validation phase of Isfahan City and by 5%, 6%, 14%, and 17%, respectively, for Tabriz City. For Isfahan, the accuracies of ME (AUROC = 0.649) and ENFA (AUROC = 0.661) one – class models were closer to that of the ANN – ME (AUROC = 0.646), ANN – ENFA (AUROC = 0.619), and RF – ENFA (AUROC = 0.631) models but differed significantly from that of the RF – ME (AUROC = 0.737) model. For Tabriz, the accuracies of ME (AUROC = 0.657) and ENFA (AUROC = 0.688) one – class models were lower than that of the two class RF-ME (AUROC = 0.852), and ANN-ME (AUROC = 0.778) models. The results showed that the ME model was able to identify relatively pure non-change samples and properly remove impure non-change samples from the training dataset. This study discovered that binary models are preferable to one-class models, and showed that an optimal sampling strategy is an essential step in UGM as it can decrease uncertainty. As such, modelers must adopt efficient sampling methods.

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  • 3.
    Al-Bahrani, Hussein Shakir
    et al.
    Faculty of Engineering, University of Kufa, Najaf, Iraq.
    Al-Rammahi, Ali Hussein
    Faculty of Engineering, University of Kufa, Najaf, Iraq.
    Al-Mamoori, Sohaib Kareem
    Department of Environmental Planning, Faculty of Physical Planning, University of Kufa, Najaf, Iraq.
    Al-Maliki, Laheab A.
    Department of Regional Planning, Faculty of Physical Planning, University of Kufa, Najaf, Iraq.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Groundwater detection and classification using remote sensing and GIS in Najaf, Iraq2022In: Groundwater for Sustainable Development, ISSN 2352-801X, Vol. 19, article id 100838Article in journal (Refereed)
    Abstract [en]

    Due to the shortage of fresh surface water caused by climate change, groundwater has become a vital water supply for household, agricultural, and industrial use. Alternative methods for determining groundwater depth, amount, and quality at a lower cost and less effort are critical. This study aims to determine the depth and kind of groundwater in Najaf City, Iraq, using Aqua detector remote sensing device. Thirty-nine sample locations were chosen in rural and urban regions to cover the city’s 441.23 square kilometres. Five geographic models of groundwater depth and type were created using the Inverse Distance Weighting (IDW) interpolation method in ArcGIS software. The results indicate that groundwater is available across the study region, beginning at 100 m and lower depths. Additionally, it has been found that the nature of groundwater fluctuates with the location and depth. The findings of this study aid in selecting wells locations and depths in the study region that generate maximum quality and quantity of groundwater.

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  • 4.
    Aziz, Maria
    et al.
    Department of Environmental Science, International Islamic University, Islamabad, Pakistan.
    Aziz, Rukhsanda
    Department of Environmental Science, International Islamic University, Islamabad, Pakistan.
    Rafiq, Muhammad Tariq
    Centre for Interdisciplinary Research in Basic Sciences, International Islamic University, Islamabad, Pakistan.
    Abbasi, Maryam
    Department of Environmental Science, International Islamic University, Islamabad, Pakistan.
    Taneez, Mehwish
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Azhar, Muhammad Usman
    Department of Earth Sciences, The University of Haripur, Haripur, Pakistan.
    El Askary, Ahmad
    Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Taif University, Taif, Saudi Arabia.
    Elesawy, Basem H.
    Department of Pathology, College of Medicine, Taif University, Taif, Saudi Arabia.
    Eed, Emad M.
    Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Taif University, Taif, Saudi Arabia.
    Khalifa, Amany S.
    Department of Clinical Pathology and Pharmaceutics, College of Pharmacy, Taif University, Taif, Saudi Arabia.
    Qayyum, Abdul
    Department of Agronomy, The University of Haripur, Haripur, Pakistan.
    Efficient Removal of Lead and Chromium From Aqueous Media Using Selenium Based Nanocomposite Supported by Orange Peel2022In: Frontiers in Environmental Science, E-ISSN 2296-665X, Vol. 10, article id 947827Article in journal (Refereed)
    Abstract [en]

    This study presents the synthesis of activated orange peel, derived from bio-waste (orange peel) and its doping with selenium nano-particles to enhance the adsorption capacity. The synthesized nanocomposite orange peel/Selenium (OP/Se) was applied as adsorbents for the removal of Lead (Pb) and Chromium (Cr) from synthetic waste water as an economical water cleaning technology. Orange peel/Selenium nanocomposite was characterized by X-Ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and Scanning electron microscopy (SEM). Scanning electron microscopy results showed the porous structure of OP/Se nanocomposite and distinct peaks observed in XRD and FTIR spectra depicted the successful synthesis of nanocomposite. Batch experiments were conducted to figure out the effect of different parameters on adsorption of Pb and Cr by using Atomic Absorption Spectroscopy. The maximum adsorption capacity of 99.9% was achieved for both lead and chromium at acidic pH. While at temperature of 60°C the maximum adsorption of 98.3 and 95.9% was found for Pb and Cr respectively. Furthermore the experimental data was examined with Pseudo-first order, first-order and Pseudo-second order kinetic model, as well as Morris Intraparticle diffusion model where the pseudo second order was best fitted which indicated the chemisorption mechanism in adsorption process. The adsorption process followed the Langmuir isotherm model verified that OP/Se nanocomposite was found to be favorable for the process of adsorption. The adsorption thermodynamics indicate that adsorption of heavy metals ions is spontaneous (ΔG° < 0) and the adsorption increases with increase in temperature which means that reaction was endothermic in nature. This study revealed that the synthesized bio-activated nanocomposite was an efficient adsorbent material for the removal of heavy metals from waste water.

  • 5.
    Baghel, Shreeya
    et al.
    Department of Soil and Water Engineering, CTAE MPUAT, Udaipur, India.
    Tripathi, M. P.
    Department of Soil and Water Engineering, SVCAET and RS, IGKV, Raipur, C.G., India.
    Khalkho, Dhiraj
    Soil and Water Engineering, Department of Soil and Water Engineering, SVCAET and RS, IGKV, Raipur, C.G., India.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Kumar, Aekesh
    Department of Soil and Water Conservation Engineering, College of Technology, Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, Uttarakhand, 263145, India.
    Elbeltagi, Ahmed
    Agricultural Engineering Department, Faculty of Agriculture, Mansoura University, Mansoura, 35516, Egypt.
    Delineation of suitable sites for groundwater recharge based on groundwater potential with RS, GIS, and AHP approach for Mand catchment of Mahanadi Basin2023In: Scientific Reports, E-ISSN 2045-2322, Vol. 13, no 1, article id 9860Article in journal (Refereed)
    Abstract [en]

    Groundwater management requires a systematic approach since it is crucial to the long-term viability of livelihoods and regional economies all over the world. There is insufficient groundwater management and difficulties in storage plans as a result of increased population, fast urbanisation, and climate change, as well as unpredictability in rainfall frequency and intensity. Groundwater exploration using remote sensing (RS) data and geographic information system (GIS) has become a breakthrough in groundwater research, assisting in the assessment, monitoring, and conservation of groundwater resources. The study region is the Mand catchment of the Mahanadi basin, covering 5332.07 km2 and is located between 21°42′15.525″N and 23°4′19.746″N latitude and 82°50′54.503″E and 83°36′1.295″E longitude in Chhattisgarh, India. The research comprises the generation of thematic maps, delineation of groundwater potential zones and the recommendation of structures for efficiently and successfully recharging groundwater utilising RS and GIS. Groundwater Potential Zones (GPZs) were identified with nine thematic layers using RS, GIS, and the Multi-Criteria Decision Analysis (MCDA) method. Satty's Analytic Hierarchy Process (AHP) was used to rank the nine parameters that were chosen. The generated GPZs map indicated regions with very low, low to medium, medium to high, and very high groundwater potential encompassing 962.44 km2, 2019.92 km2, 969.19 km2, and 1380.42 km2 of the study region, respectively. The GPZs map was found to be very accurate when compared with the groundwater fluctuation map, and it is used to manage groundwater resources in the Mand catchment. The runoff of the study area can be accommodated by the computing subsurface storage capacity, which will raise groundwater levels in the low and low to medium GPZs. According to the study results, various groundwater recharge structures such as farm ponds, check dams and percolation tanks were suggested in appropriate locations of the Mand catchment to boost groundwater conditions and meet the shortage of water resources in agriculture and domestic use. This study demonstrates that the integration of GIS can provide an efficient and effective platform for convergent analysis of various data sets for groundwater management and planning.

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  • 6.
    Bascunan, Daniel
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    LCC-analys parametrar för underhåll av inklädda tunnlar2020Independent thesis Basic level (professional degree), 180 HE creditsStudent thesis
    Abstract [sv]

    Syftet med detta examensarbete är att undersöka och få fram underhållsparametrar för LCC-analysen (LivsCykelKostnad) av de nya inklädda tunnlarna. För arbetet har elektroniska källor använts samt intervjuer med tre yrkesverksamma från Trafikverket gällande bergtunnlar och de inklädda tunnlarna. Arbetet undersökte inte skillnaden mellan olika typer av tunnlar samt inkluderar inte utforskandet av andra länders LCC-analys parameterval.

    Trafikverket är en Svensk myndighet vars uppgift är att ansvara för och upprätthålla Sveriges transportsystem. Trafikverket har verksamhet inom sex områden: planering, trafik, underhåll, investering, stora projekt samt informations- och kommunikationsteknik.

    Huvudsakligen finns det två inklädnadssystem, fullinklädd, i vilket används antingen prefabricerad betong eller plastingjuten betong som inklädnad runt tunnel, samt halvinklädd, då en duk/membran med- eller utan sprutbetong används. Dessa inklädnadsystem har i uppgift att ta hand om vattenläckage och isbildning i tunneln. Fullinklädnad kan också användas som bärande element. En lättinklädd tunnel kan bestå av följande delar: duk/membranet, brandskydd, täckande nät, infästningsbultar och mindre delar. En fullinklädd tunnel består av antingen prefabricerad betong eller plastingjuten betong.

    Underhåll görs för att säkerställa den fortlöpande användningen av tunneln/anläggningen genom att åtgärda skador och fel som har uppkommit. En tunnel kan få skador på själva berget eller materialet. Underhåll av tunnlar består av flera steg. Först ut är tillståndsmätning, sedan objektplanering och sist åtgärd. En viktig del av åtgärd är trafikupphållet som uppstår när den utförs, kostnaden som uppstår påverkas av var tunneln är och hur länge det tar att åtgärda felet.

    LCC-analys är ett system som ger ett mått på ett objekts totalkostnad under dess hela livstid. LCC används på systemnivå för analys av tunnlarna och för att jämföra olika investeringsmetoder. För att utföra LCC-analys på systemnivå måste gränser för analysen sättas upp, LCC-modell och indata väljas. LCC-metoden som redovisas i rapporten använder investeringskostnaden och nuvärdet av underhållet- samt driftstoppskostnaden för att få fram LCC-värdet av underhållet för en komponent.

    Utifrån källorna och intervjuerna har det framgått att de avgörande parametrarna för LLC-analysen är följande: bergets tillstånd, materialets/konstruktionens tillstånd, kostnader för avstängning samt kostnaden för att ta ner inklädnaden.

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  • 7.
    Gałaś, Andrzej
    et al.
    Mineral and Energy Economy Research Institute, Polish Academy of Sciences, Division of Mineral Policy, Wybickiego 7A, 31-261, Krakow, Poland.
    Kot-Niewiadomska, Alicja
    Mineral and Energy Economy Research Institute, Polish Academy of Sciences, Division of Mineral Policy, Wybickiego 7A, 31-261, Krakow, Poland.
    Simić, Vladimir
    University of Belgrade, Faculty of Mining and Geology, Belgrade, Serbia.
    Tost, Michael
    Montanuniversität Leoben, Mining Engineering and Mineral Economics, Leoben, Austria.
    Wårell, Linda
    Luleå University of Technology, Department of Social Sciences, Technology and Arts, Social Sciences.
    Gałaś, Slávka
    AGH University of Krakow, Faculty of Geology, Geophysics and Environmental Protection, Krakow, Poland.
    A comparative case-study on social and public administration aspects on mineral deposits safeguarding in chosen European countries2023In: Resources policy, ISSN 0301-4207, E-ISSN 1873-7641, Vol. 85, no part B, article id 103863Article in journal (Refereed)
    Abstract [en]

    Representatives of the municipality decide about the country's resources, making decisions at the local level in spatial planning. Our task was to check whether they are aware of how important they are taking steps for the region and country. For this purpose, a survey was conducted in Poland, Austria, Serbia and Sweden. The analysis of the received responses indicates that the respondents know the deposits of raw materials in their area of work. However, they only partially perceive the need to protect them against development that may sterilize the raw material. The analysis shows that the respondents, do not consider of non-renewable mineral resources wider importance against the background of public interest. Additionally, there is no rational assessment of the consequences of losing non-renewable resources through planning decisions. We notice that the national guidelines, where a wider perspective can be present, should be clearer regarding the importance of safeguarding minerals – so that development that hampers their future use is avoided. The changing geopolitical situation makes it necessary to raise awareness about the problem of raw material security and reconsider the systems to safeguard them.

  • 8.
    Harrison, S. K.
    et al.
    Geography Department, Staffordshire University, Science Centre, Leek Road, Stoke-on-Trent, ST4 2DF, UK.
    Balme, M. R.
    Geography Department, Staffordshire University, Science Centre, Leek Road, Stoke-on-Trent, ST4 2DF, UK; Planetary Science Institute, 1700 East Fort Lowell, Suite 106, Tucson, AZ 85719, USA.
    Hagermann, Axel
    Department of Physical Science, The Open University, Walton Hall, Milton Keynes, MK7 6AA, UK.
    Murray, J. B.
    Environment, Earth and Ecosystems, The Open University, Walton Hall, Milton Keynes, MK7 6AA, UK.
    Muller, J. -P
    University College London, Department of Space & Climate Physics, Mullard Space Science Laboratory, Holmbury St. Mary, Dorking, RH5 6NT, UK.
    Wilson, A.
    Department of Physical Science, The Open University, Walton Hall, Milton Keynes, MK7 6AA, UK.
    A branching, positive relief network in the middle member of the Medusae Fossae Formation, equatorial Mars - Evidence for sapping?2013In: Planetary and Space Science, Vol. 85, p. 142-163Article in journal (Refereed)
  • 9.
    Hultenberg, Sten
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    En jämförelse mellan två termiska saneringsmetoder: Elektrisk konduktiv uppvärmning och Elektrisk resistivitetsuppvärmning utifrån genomförda projekt i Sverige samt Nordamerika2020Independent thesis Advanced level (professional degree), 300 HE creditsStudent thesis
    Abstract [sv]

    I nuläget existerar det 85 000 områden i Sverige som är eller misstänks vara kontaminerade. Dessa områden behöver minskas för att miljökvalitetsmålet om en Giftfri miljö ska uppnås. Saneringen kan ske på olika sätt varav schaktsanering är den vanligaste. Det är en ex-situ metod som innebär att föroreningen grävs upp och förflyttas till annan plats där själva reningen sker. En annan metod är termisk in-situ sanering, vilket är när man behandlar föroreningen direkt i marken med hjälp av värme. Inom termisk behandlings brukar metoderna Elektrisk konduktiv uppvärmning (ECH) och Elektrisk resistivitetsuppvärmning (ERH) användas. ECH är en metod som beror på markens elektriska konduktivitet dvs markens förmåga att transportera elektrisk laddning. I behandlingsområdet installeras värmeelement som blir varma och sprider värmen till jorden. På så vis uppnås önskvärd temperatur och föroreningen förångas. Gasen samlas sedan upp vid markytan och renas. ERH är en metod som använder sig av elektrisk resistivitet dvs markens elektriska motståndsförmåga för att alstra värme. Elektroder installeras i behandlingsområdet som skickar ut elektrisk ström till jorden. Marken gör motstånd och värme alstras.

    Syftet med denna studie är att dels fördjupa sig i hur dessa metoder fungerar och att jämföra dem utifrån tekniska- och ekonomiska aspekter. Kan en av metoderna klassificeras som billigare och effektivare än den andra. En fallstudie genomfördes där sex förorenade områden med klorerande lösningsmedel studerades. Dessutom studerades tidigare undersökningar om metoderna. En statistisk bearbetning genomfördes för att se korrelationen mellan parametrarna.

    Utvärdering från fallstudien indikerade att det finns en stor skillnad mellan metoderna. Parametrarna: kostnad, energikonsumtion, reningseffektivitet och behandlingstid jämfördes mellan metoderna. Jämförelsen visade på att ERH har en högre kostnad, energikonsumtion och längre behandlingstid än ECH. Reningseffektiviteten är några procent högre för ECH, men båda åstadkommer över 95% rening. Däremot existerar det förutsatta meningar angående vilken metod som har högst energikonsumtion. Enligt tidigare studier påvisas det att ECH kräver mer energi än ERH vilket motsäger denna studie. Det krävs därför ytterligare undersökning för att fastställa det. Slutsatsen är därför att ECH är billigare, effektivare och snabbare än ERH.

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  • 10.
    Kaufmann, E.
    et al.
    Department of Physical Sciences, The Open University, Walton Hall, Milton Keynes MK7 6AA, UK.
    Hagermann, A.
    Department of Physical Sciences, The Open University, Walton Hall, Milton Keynes MK7 6AA, UK.
    Penetration of solar radiation into pure and Mars-dust contaminated snow2015In: Icarus, ISSN 0019-1035, Vol. 252, p. 144-149Article in journal (Refereed)
  • 11.
    Kaufmann, Erika
    et al.
    Department of Physical Sciences, The Open University, Walton Hall, Milton Keynes, MK7 6AA, UK.
    Hagermann, Axel
    Department of Physical Sciences, The Open University, Walton Hall, Milton Keynes, MK7 6AA, UK.
    Experimental investigation of insolation-driven dust ejection from Mars'€™ CO2 ice caps2017In: Icarus, ISSN 0019-1035, Vol. 282, p. 118-126Article in journal (Refereed)
  • 12.
    Kreuzig, C.
    et al.
    Institut für Geophysik und extraterrestrische Physik (IGeP), TU Braunschweig, Mendelssohnstr. 3, 38106 Braunschweig, Germany.
    Kargl, G.
    Space Research Institute, Austrian Academy of Science, Schmiedlstraße 6, 8042 Graz, Austria.
    Pommerol, A.
    Physics Institute for Space Research and Planetary Science, University of Bern, Sidlerstrasse 5, 3012 Bern, Switzerland.
    Knollenberg, J.
    Deutsches Zentrum für Luft- und Raumfahrt, Rutherfordstraße 2, 12489 Berlin-Adlershof, Germany.
    Lethuillier, A.
    Institut für Geophysik und extraterrestrische Physik (IGeP), TU Braunschweig, Mendelssohnstr. 3, 38106 Braunschweig, Germany.
    Molinski, N. S.
    Institut für Geophysik und extraterrestrische Physik (IGeP), TU Braunschweig, Mendelssohnstr. 3, 38106 Braunschweig, Germany.
    Gilke, T.
    Institut für Geophysik und extraterrestrische Physik (IGeP), TU Braunschweig, Mendelssohnstr. 3, 38106 Braunschweig, Germany.
    Bischoff, D.
    Institut für Geophysik und extraterrestrische Physik (IGeP), TU Braunschweig, Mendelssohnstr. 3, 38106 Braunschweig, Germany.
    Feller, C.
    Physics Institute for Space Research and Planetary Science, University of Bern, Sidlerstrasse 5, 3012 Bern, Switzerland.
    Kührt, E.
    Deutsches Zentrum für Luft- und Raumfahrt, Rutherfordstraße 2, 12489 Berlin-Adlershof, Germany.
    Sierks, H.
    Max-Planck-Institut für Sonnensystemforschung, Justus-von-Liebig-Weg 3, 37077 Göttingen, Germany.
    Hänni, N.
    Physics Institute for Space Research and Planetary Science, University of Bern, Sidlerstrasse 5, 3012 Bern, Switzerland.
    Capelo, H.
    Physics Institute for Space Research and Planetary Science, University of Bern, Sidlerstrasse 5, 3012 Bern, Switzerland.
    Güttler, C.
    Max-Planck-Institut für Sonnensystemforschung, Justus-von-Liebig-Weg 3, 37077 Göttingen, Germany.
    Haack, D.
    Deutsches Zentrum für Luft- und Raumfahrt, Rutherfordstraße 2, 12489 Berlin-Adlershof, Germany.
    Otto, K.
    Deutsches Zentrum für Luft- und Raumfahrt, Rutherfordstraße 2, 12489 Berlin-Adlershof, Germany.
    Kaufmann, Erika
    Space Research Institute, Austrian Academy of Science, Schmiedlstraße 6, 8042 Graz, Austria.
    Schweighart, M.
    Space Research Institute, Austrian Academy of Science, Schmiedlstraße 6, 8042 Graz, Austria.
    Macher, W.
    Space Research Institute, Austrian Academy of Science, Schmiedlstraße 6, 8042 Graz, Austria.
    Tiefenbacher, P.
    Space Research Institute, Austrian Academy of Science, Schmiedlstraße 6, 8042 Graz, Austria.
    Gundlach, B.
    Institut für Geophysik und extraterrestrische Physik (IGeP), TU Braunschweig, Mendelssohnstr. 3, 38106 Braunschweig, Germany.
    Blum, J.
    Institut für Geophysik und extraterrestrische Physik (IGeP), TU Braunschweig, Mendelssohnstr. 3, 38106 Braunschweig, Germany.
    The CoPhyLab comet-simulation chamber2021In: Review of Scientific Instruments, ISSN 0034-6748, E-ISSN 1089-7623, Vol. 92, no 11, p. 115102-115102Article in journal (Refereed)
    Abstract [en]

    The Comet Physics Laboratory (CoPhyLab) is an international research program to study the physical properties of cometary analog materials under simulated space conditions. The project is dedicated to studying, with the help of multiple instruments and the different expertise and background from the different partners, the physics of comets, including the processes inside cometary nuclei, the activity leading to the ejection of dust and gas, and the sub-surface and surface evolution of cometary nuclei when exposed to solar illumination. CoPhyLab will provide essential information on the formation and evolution of comets and insights into the origins of primitive Solar System bodies. To this end, we constructed a new laboratory that hosts several small-scale experiments and a large-scale comet-simulation chamber (L-Chamber). This chamber has been designed and constructed to host ice–dust samples with a diameter of up to 250 mm and a variable height between 100 and 300 mm. The cometary-analog samples will be kept at temperatures below 120 K and pressures around 10−6 mbar to ensure cometary-like conditions. In total, 14 different scientific instruments are attached to the L-Chamber to study the temporal evolution of the physical properties of the sample under different insolation conditions. Due to the implementation of a scale inside the L-Chamber that can measure weight changes of the samples with high precision, the cooling system is mechanically decoupled from the sample holder and cooling of the samples occurs by radiation only. The constructed chamber allows us to conduct uninterrupted experiments at low temperatures and pressures up to several weeks.

  • 13.
    Kumar, Praveen
    et al.
    Department of Remote Sensing, BIT Mesra, Ranchi, 835 215, Jharkhand, India.
    Krishna, Akhouri P.
    Department of Remote Sensing, BIT Mesra, Ranchi, 835 215, Jharkhand, India.
    Rasmussen, Thorkild Maack
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Pal, Mahendra K.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    An Approach for Fraction of Vegetation Cover Estimation in Forest Above-Ground Biomass Assessment Using Sentinel-2 Images2021In: Computer Vision and Image Processing: 5th International Conference, CVIP 2020, Prayagraj, India, December 4-6, 2020, Revised Selected Papers, Part I / [ed] Satish Kumar Singh; Partha Roy; Balasubramanian Raman; P. Nagabhushan, Springer Nature, 2021, p. 1-11Conference paper (Refereed)
    Abstract [en]

    Forests are one of the most important components to balance and regulate the terrestrial ecosystem on the Earth in protecting the environment. Accurate forest above-ground biomass (AGB) assessment is vital for sustainable forest management to recognize climate change and deforestation for mitigation processes. In this study, Sentinel 2 remote sensing image has been used to calculate the fraction of vegetation cover (FVC) in order to accurately estimate the forest above-ground biomass of Tundi reserved forest in the Dhanbad district located in the Jharkhand state, India. The FVC is calculated in four steps: first, vegetation index image generation; second, vegetation index image rescaled between 0 to 1; third, the ratio of vegetated and non-vegetated areas was calculated with respect to the total image area, and finally, FVC image is generated. In this paper, three vegetation indices have been calculated from the Sentinel 2 image, namely: normalized difference vegetation index (NDVI), normalized difference index 45 (NDI45), and inverted red-edge chlorophyll index (IRECI). Then, the FVC images were generated from the above vegetation indices individually. The ground FVC values were estimated from 22 different locations from the study area. Finally, the image based FVC estimates were compared with the ground estimated FVC. The results show that the IRECI based FVC provided the best approximation to the ground FVC among the different vegetation indices tested.

  • 14.
    Lönnqvist, Joel
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Blecken, Godecke-Tobias
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Evaluating the plant cover of northern Sweden's green roofs2017In: Proceedings of EtW2017, 2017Conference paper (Other academic)
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  • 15.
    Michikami, T.
    et al.
    Faculty of Engineering, Kinki University, Hiroshima Campus, 1 Takaya Umenobe, Higashi-Hiroshima, Hiroshima 739-2116, Japan.
    Hagermann, A.
    Department of Physical Sciences, The Open University, Walton Hall, Milton Keynes MK7 6AA, United Kingdom.
    Miyamoto, H.
    The University Museum, University of Tokyo, Hongo 7-3-1, Bunkyoku, Tokyo 113-0033, Japan.
    Miura, S.
    Tokuyama College of Technology, Shunan, Yamaguchi 745-8585, Japan.
    Haruyama, J.
    Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa 252-8510, Japan.
    Lykawka, P. S.
    Astronomy Group, Faculty of Social and Natural Sciences, Kinki University, Higashi-osaka, Osaka 577-0813, Japan.
    Impact cratering experiments in brittle targets with variable thickness: Implications for deep pit craters on Mars2014In: Planetary and Space Science, ISSN 0032-0633, Vol. 96, p. 71-80Article in journal (Refereed)
  • 16.
    Morata, Berta
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    "Hic et Nunc" Palimpsests. Reconstructing Historical Natures through the Malm Territory of Extraction2022In: A Landscape Approach: From Local Communities to Territorial Systems / [ed] Hannes Zander, Shelagh McCartney, Samantha Solano, Sonja Vangjeli, Novato: Oro Editions , 2022, 1, p. 169-179Chapter in book (Refereed)
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  • 17.
    Morgan, P.
    et al.
    Colorado Geological Survey, Colorado School of Mines, 1801 19th St., Golden, CO, 80401, USA.
    Grott, M.
    DLR Institute for Planetary Research, Rutherfordstr. 2, 12489, Berlin, Germany.
    Knapmeyer-Endrun, B.
    Department Planets and Comets, Max Plank Institute for Solar System Research, Justus-von-Liebig-Weg 3, 37077, Göttinggen, Germany.
    Golombek, M.
    Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., Pasadena, CA, 91109, USA.
    Delage, P.
    Ecole des Ponts ParisTech, Laboratoire Navier (CERMES), Paris, France.
    Lognonné, P.
    Institut de Physique du Globe de Paris – Sorbonne Paris Cité, Université Paris Diderot, 35 rue Hélène Brion, 75013, Paris, France.
    Piqueux, S.
    Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., Pasadena, CA, 91109, USA.
    Daubar, I.
    Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., Pasadena, CA, 91109, USA.
    Murdoch, N.
    Institut Supérieur de l’Aéronautique et de l’Espace (ISAE-SUPAERO), Université de Toulouse, 31055, Toulouse Cedex 4, France.
    Charalambous, C.
    Faculty of Engineering, Department of Electrical and Electronic Engineering, Imperial College London, London, UK.
    Pike, W. T.
    Faculty of Engineering, Department of Electrical and Electronic Engineering, Imperial College London, London, UK.
    Müller, N.
    Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., Pasadena, CA, 91109, USA.
    Hagermann, Axel
    Faculty of Science Technology and Mathematics, The Open University, Walton Hall, Milton Keynes, MK7 6AA, UK.
    Siegler, M.
    Deadman College of Humanities and Sciences, Southern Methodist University, PO Box 750235, Dallas, TX, 75275-0235, USA.
    Lichtenheldt, R.
    DLR Institute for System Dynamics and Control, Münchner Straße 20, 82234, Oberpfaffenhofen-Weßling, Germany.
    Teanby, N.
    School of Earth Sciences, University of Bristol, Wills Memorial Building, Queens Road, Clifton, BS8 1RJ, UK.
    Kedar, S.
    Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., Pasadena, CA, 91109, USA.
    A Pre-Landing Assessment of Regolith Properties at the InSight Landing Site2018In: Space Science Reviews, Vol. 214, no 6Article in journal (Refereed)
  • 18.
    Ngo, Phuong Linh
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Detection of in-plane orbital manoeuvres from a catalogue of geostationary objects2020Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The number of man-made space objects is dramatically growing nowadays. The continuous monitoring and studying of these objects are necessary to keep their number under control and ensure safe space operations. With respect thereto, international guidelines recommend decongesting the most populated space regions from satellites arriving at the end of their operational lifetime by performing post-mission disposal strategies. In general, a satellite is considered to be functional if it is still performing periodic manoeuvres to stay within the orbital operation configuration. This study presents a promising method to detect historical in-plane manoeuvrers of satellites on a geostationary orbit (GEO). Since a manoeuvrer changes the orbital state of the spacecraft, its effect can be detected by comparing the observed data to a reference evolution. In this case, the  model is represented by the dynamical model STELA  based on a semi-analytical theory. The observed data is provided by the public American space object catalogue. The Two-line element (TLE) database contains the orbital state of each tracked object, however, not all six orbital parameters are interesting to study in terms of in- plane manoeuvrers. The evolution of the longitude and of the eccentricity vector is immediately affected by a manoeuvre that changes the shape or the size of an orbit. Within the longitude analysis, the manoeuvre epoch is estimated by focusing on the manoeuvre strategy. An operational spacecraft usually performs a manoeuvre as soon as the longitude motion threatens to violate the operational deadband. Consequently, the longitude evolution follows a parabolic motion. Two polynomial curves of second degree are laid over the observation: the first curve is derived from a simplified dynamical model and the second curve is directly obtained through a Least Squares (LS) fitting method. The discrepancy between the LS and physical fitted parabolas gives an indication on the quality of the input data, that is to say, of the TLEs. The detected manoeuvre epoch must be companioned by a confidential parameter that denotes the time range around the estimated epoch in which the manoeuvre is expected to have happened. The manoeuvre interval is then forwarded to the eccentricity analysis where the manoeuvrer epoch is estimated more precisely by studying the divergence between the observed and expected eccentricity vector evolution. The latter is propagated with STELA after having estimated the area-to-mass ratio that is needed in order to model the perturbation effects accurately upon which the performance of the dynamical reference model strongly depends. As soon as the observed eccentricity vector deviates significantly from the expected evolution, the epoch and the velocity ΔV of the manoeuvre can be recovered, too.

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  • 19.
    Nigéus, Susanne
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Maurice, Christian
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering. Ramböll Sverige AB, Kyrkogatan 2, Box 850, SE-97126 Luleå, Sweden.
    Lindblom, Jenny
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Water Retention Capacity as a Measure to Evaluate the Effectiveness of a Green Liquor Dregs-Amended Till to Cover Sulfidic Mine Waste2022In: IMWA 2022 Conference - "Reconnect": Proceedings of the International Mine Water Association Conference / [ed] James Pope; Christian Wolkersdorfer; Rachel Rait; Dave Trumm; Hana Christenson; Karoline Wolkersdorfer, International Mine Water Association 2023 , 2022, p. 337-344Conference paper (Refereed)
    Abstract [en]

    Hydraulic conductivity is often used as a measure to evaluate the effectiveness of a sealing layer material on top of mine waste. However, the most important soil parameter minimizing the oxygen diffusion to the mine waste is the water retention capacity (WRC) of the sealing layer, as a high saturation corresponds to a low oxygen diffusion rate. This study shows that an amendment of Green Liquor Dregs (GLD), an industrial residue, to a till increases its WRC and has therefore potential to be a more accurate method to evaluate the effectiveness of a sealing layer than hydraulic conductivity.

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  • 20.
    Norin, Lars
    et al.
    Department of Radar Electronic Warfare Systems, Swedish Defence Research Agency, Linköping, Sweden.
    Wellander, Niklas
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Mathematical Science. Department of Radar Systems, Swedish Defence Research Agency, Linköping, Sweden.
    Devasthale, Abhay
    Meteorological Research Unit, Swedish Meteorological and Hydrological Institute, Norrköping, Sweden.
    Anomalous Propagation and the Sinking of the Russian Warship Moskva2023In: Bulletin of The American Meteorological Society - (BAMS), ISSN 0003-0007, E-ISSN 1520-0477, Vol. 104, no 12, p. E2286-E2304Article in journal (Refereed)
    Abstract [en]

    On 13 April 2022, the Russian warship Moskva was hit by two Ukrainian Neptune anti-ship missiles in the Black Sea, leading to its demise. Before launching an anti-ship missile, a target must first be detected and positioned, for example, by an accompanying radar system. However, when the missiles hit the Moskva she was well beyond the normal radar horizon of any ground-based radar system, making the ship undetectable under normal circumstances. Using meteorological reanalysis data, we show that at the time of the missile launch the prevailing weather conditions allowed a ground-based radar to detect targets far beyond the normal radar horizon through anomalous propagation conditions. During such conditions, the atmospheric index of refraction decreases rapidly with height, making electromagnetic radiation bend downward to, partly or fully, compensate the curvature of the Earth. The results show that atmospheric conditions must be considered carefully, even during warfare, as their impact on radar wave propagation can be considerable.

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  • 21.
    Patel, Daniel
    et al.
    Rapid Geology AS and Western Norway University of Applied Sciences (HVL), Bergen, Norway.
    Langeland, Tor
    NORCE Research, Bergen, Norway.
    Tavakoli, Saman
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Fjeld, Morten
    University of Bergen, Bergen, Norway.
    Groupware for Research on Subsurface CO2 Storage2021In: Interactive Data Processing and 3D Visualization of the Solid Earth / [ed] Daniel Patel, Springer, 2021, 1, p. 291-323Chapter in book (Other academic)
    Abstract [en]

    Directed towards the multidisciplinary research field on carbon capture and storage (CCS), this paper reports empirically on progress towards a groupware system (collaborative software) and experiences learned when creating groupware for CCS research. As subsurface CO2 storage requires collaboration across a wide range of CCS disciplines, we describe the collaborative challenges faced and how our proposed groupware addresses these, and present criteria for CCS groupware and a field study over three iterations evaluating how well various software systems fulfill those criteria. In iteration one, we evaluate a commercial and feature-rich stand-alone application used together with a conferencing application. Based on this evaluation, in iteration two we develop and evaluate a custom-built lightweight web application. In the third and last iteration, we present a prototype that uses the most useful features from the two evaluated solutions. Finally, we give a suggestion of how to implement a groupware fulfilling all requirements identified for a successful CCS groupware.

  • 22.
    Paton, M. D.
    et al.
    Finnish Meteorological Institute, PO Box 503, FIN-00101 Helsinki, Finland.
    Harri, A.-M.
    Finnish Meteorological Institute, PO Box 503, FIN-00101 Helsinki, Finland.
    Savijärvi, H.
    Department of Physics, University of Helsinki, FI-00560 Finland.
    Mäkinen, T.
    Finnish Meteorological Institute, PO Box 503, FIN-00101 Helsinki, Finland.
    Hagermann, Axel
    Department of Physical Sciences, The Open University, Milton Keynes MK7 6AA, UK.
    Kemppinen, O.
    Finnish Meteorological Institute, PO Box 503, FIN-00101 Helsinki, Finland.
    Johnston, A.
    Center for Earth and Planetary Studies, National Air and Space Museum, Washington, DC 20013-7012, USA.
    Thermal and microstructural properties of fine-grained material at the Viking Lander 1 site2016In: Icarus, ISSN 0019-1035, Vol. 271, p. 360-374Article in journal (Refereed)
  • 23.
    Rapa, Mattia
    et al.
    Department of Management, Sapienza University of Rome, Rome, Italy.
    Ferrante, Marco
    Trace Technologies S.r.l., Nereto, Teramo, Italy.
    Rodushkin, Ilia
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering. ALS Laboratory Group, ALS Scandinavia AB, Luleå, Sweden.
    Paulukat, Cora
    ALS Laboratory Group, ALS Scandinavia AB, Luleå, Sweden.
    Conti, Marcelo Enrique
    Department of Management, Sapienza University of Rome, Rome, Italy.
    Venetian Protected Designation of origin wines traceability: Multi-elemental, isotopes and chemometric analysis2023In: Food Chemistry, ISSN 0308-8146, E-ISSN 1873-7072, Vol. 404, no Part B, article id 134771Article in journal (Refereed)
    Abstract [en]

    The traceability and authentication of PDOs wines are important issues for safeguarding their production and distribution systems. This paper evaluated seven Venetian PDO wines, i.e., Amarone, Bardolino, Custoza, Pinot Grigio, Recioto, Soave and Valpolicella. For this purpose, 219 wine samples from the Veneto region were characterised by determining 63 elements and six isotope ratios by HR-ICP-MS and MC-ICP-MS. Chemometric tools highlighted As, Ca, Cs, δ11B and 87Sr/86Sr as the most informative variables to differentiate the PDOs. Seven classification methods, such as Linear Discriminant Analysis, Quadratic Discriminant Analysis, k-Nearest Neighbours, Naïve Bayes, Random Forest, Artificial Neural Networking, and Support Vector Machine were tested and perform a correct classification for Amarone, Bardolino, Pinot Grigio and Recioto PDOs. This paper successfully proposes for the first time advanced traceability tools of seven Venetian PDO by the use of an integrated approach of multi-elemental and isotopes followed by chemometrics analysis.

  • 24.
    Rivera, Javier
    et al.
    Department of Geology and Andean Geothermal Center of Excellence (CEGA), FCFM, Universidad de Chile, Santiago, Chile.
    Reich, Martin
    Department of Geology and Andean Geothermal Center of Excellence (CEGA), FCFM, Universidad de Chile, Santiago, Chile.
    Schoenberg, Ronny
    Department of Geosciences, University of Tübingen, Tübingen, Germany.
    González Jiménez, José María
    Departmento de Mineralogía y Petrología, Facultad de Ciencias, Universidad de Granada, Spain.
    Barra, Fernando
    Department of Geology and Andean Geothermal Center of Excellence (CEGA), FCFM, Universidad de Chile, Santiago, Chile.
    Aiglsperger, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Proenza, Joaquín
    Departament de Mineralogia, Petrologia i Geologia Aplicada, Universitat de Barcelona (UB), Barcelona, Spain.
    Carretier, Sebastien
    GET, Université de Toulouse, CNRS, IRD, Toulouse, France.
    Platinum-group element and gold enrichment in soils monitored by chromium stable isotopes during weathering of ultramafic rocks2018In: Chemical Geology, ISSN 0009-2541, E-ISSN 1872-6836, Vol. 499, p. 84-99Article in journal (Refereed)
    Abstract [en]

    Weathering of ultramafic rocks can lead to the formation of soil profiles with high contents of Fe, Ni, Co, platinum-group elements (PGE) and gold. Traditionally, these metal-rich soils are known as “laterites” and are formed under tropical climates and stable tectonic conditions. However, little is known about their possible development in cold/humid regions, and the factors governing PGE and gold mobility and enrichment under these weathering conditions are poorly constrained. In this study, five soil profiles developed on serpentinized, chromite-bearing ultramafic rocks at La Cabaña, located in the Coastal Range of south-central Chile (38° S) were studied by combining major and trace element geochemistry with chromium stable isotope data. The results show that the soils developed at La Cabaña have higher PGE and Au contents than the parent serpentinite rock, with ∑PGE and Au reaching up to 160 ppb and 29 ppb in a limonitic soil horizon and clay saprolite, respectively. Most soil samples have slightly negative δ53/52CrSRM979 values, within a range of −0.089 ± 0.012‰ to −0.320 ± 0.013‰ (average of −0.178‰), and are in agreement with previous data reported for modern soils. A noteworthy relation between δ53/52Cr data and PGE + Au contents is observed in the studied soil horizons, where isotopically lighter values of δ53/52Cr match the higher contents of PGE and gold. These results show that pedogenetic processes operating at the cold and humid La Cabaña area are capable of increasing the total PGE and Au contents of certain soil horizons. Such processes are complex and multivariate but are primarily modulated by chromite dissolution and the formation of secondary phases such as clay minerals and oxy-hydroxide phases in the soil. These findings provide evidence that important weathering and PGE + Au supergene accumulation are not only restricted to tropical latitudes, and that the chromium isotope system is a useful proxy to track surface redox process and noble metal enrichment during pedogenesis.

  • 25.
    Sambandham, Venkatesh Thirugnana
    et al.
    BASF Digital Farming GmbH.
    Shankar, Priyamvada
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab. BASF Digital Farming GmbH.
    Mukhopadhaya, Sayan
    BASF Digital Farming GmbH.
    Early Onset Yellow Rust Detection Guided By Remote Sensing Indices2022In: Remote Sensing, E-ISSN 2072-4292Article in journal (Refereed)
    Abstract [en]

    Early warning systems help combat crop diseases and enable sustainable plant protection by optimizing the use of resources. The application of remote sensing to detect plant diseases like Wheat stripe rust, commonly known as yellow rust is based on the presumption, that the presence of a disease has a direct link with the photosynthesis capability and physical structure of a plant at both canopy and tissue level. This causes changes to the solar radiation absorption capability and thus alters the reflectance spectrum. In comparison to existing methods and technologies, remote sensing offers access to near real time information at both field and regional scale to build robust disease models. This study shows the capability of multispectral images along with weather, in-situ  and phenology data to detect the onset of yellow rust disease.  Crop details and disease observation data from field trials across the globe spanning four years (2015-2018) are combined with weather data to model disease severity over time as a value between 0-1 with 0 being no disease and 1 being the highest infestation level. Various tree based ensemble algorithms like CatBoost, Random Forest and XGBoost has been experimented with. The XGBoost model performs best with a mean absolute error of 0.1568 and root mean square error of 0.2081. Being a fast-spreading disease and having caused epidemics in the past, the above model alone is not enough. It is important to detect yellow rust disease early so farmers can be warned in advance and favorable management practices can be implemented. Vegetation indices like NDVI, NDRE and NDWI from remote sensing images have been used as auxiliary features along with disease severity predictions over time derived from the previous step to detect early onset of the disease. A rule-based approach is presented that uses a combination of both model output and changes in vegetation indices to predict an early disease progression window. Analysis on test trials shows that in 80% of the cases, the predicted progression window was ahead of the first disease observation on the field offering an opportunity to take timely action that could save yield. 

  • 26.
    Sjöberg, J.
    et al.
    Itasca Consultants AB, Sweden.
    Bolin, A.
    Itasca Consultants AB, Sweden.
    Sanchez Juncal, A.
    University of Alberta, Canada.
    Wettainen, T.
    LKAB, Sweden.
    Mas Ivars, D.
    Itasca Consultants AB, Sweden.
    Perman, F.
    Itasca Consultants AB, Sweden.
    Input to orepass design: a numerical modelling study2015In: International Seminar on Design Methods in Underground Mining / [ed] Yves Potvin, Perth: Australian Centre for Geomechanics, 2015, p. 571-584Conference paper (Refereed)
  • 27.
    Sjöberg, Jonny
    Itasca Consulting Group, Inc., 708 South Third Street, Suite 310, 55415, Minneapolis, MN, USA.
    Design Methods for Stopes and Sill Pillars with Application to the Zinkgruvan Mine, Central Sweden1993In: Rock Mechanics and Rock Engineering, ISSN 0723-2632, E-ISSN 1434-453X, Vol. 26, p. 253-275Article in journal (Refereed)
  • 28.
    Sjöberg, Jonny
    Itasca Consultants AB, Sweden.
    Numerical analysis, slope design and in situ stress2013In: 2013 International Symposium on Slope Stability in Open Pit Mining and Civil Engineering / [ed] P.M. Dight, Perth, 2013, p. 29-42Conference paper (Refereed)
  • 29.
    Sjöberg, Jonny
    et al.
    SwedPower AB, Luleå 97177, Sweden.
    Christiansson, Rolf
    Hudson, John
    ISRM Suggested Methods for rock stress estimation—Part 2: overcoring methods2003In: International Journal of Rock Mechanics And Mining Sciences, ISSN 1365-1609, E-ISSN 1873-4545, no 7-8, p. 999-1010Article in journal (Refereed)
  • 30.
    Sjöberg, Jonny
    et al.
    Itasca Consultants AB, Sweden.
    Cotesta, Luigi
    Paudel, Binod
    Sterrett, Robert
    Dilov, Tzvetan
    Vasilev, Ivan
    Yalamov, Zhelyazko
    Advanced three-dimensional geomechanical and hydrogeological modelling for a deep open pit2020In: 2020 International Symposium on Slope Stability in Open Pit Mining and Civil Engineering / [ed] P.M. Dight, Perth: Australian Centre for Geomechanics, 2020, p. 1383-1398Conference paper (Refereed)
  • 31.
    Sjöberg, Jonny
    et al.
    Itasca Consultants AB, Sweden.
    Edelbro, Catrin
    Pierce, Matt
    Sandström, Daniel
    Raiseboring in difficult rock conditions2019In: Ninth International Symposium on Ground Support in Mining and Underground Construction / [ed] Hadjigeorgiou J. & Hudyma, M, 2019, p. 185-198Conference paper (Refereed)
  • 32.
    Sjöberg, Jonny
    et al.
    SwedPower AB, Luleå, Sweden.
    Klasson, Hans
    Stress Measurements in Deep Boreholes Using the Borre (SSPB) Probe2003In: International Journal of Rock Mechanics And Mining Sciences, ISSN 1365-1609, E-ISSN 1873-4545, Vol. 40, no 7-8, p. 1205-1223Article in journal (Refereed)
  • 33.
    Sjöberg, Jonny
    et al.
    Itasca Consultants AB, Sweden.
    Mäkitaavola, Karola
    Stöckel, Britt-Mari
    Savilahti, Thomas
    Dudley, Jon
    McParland, Mary Anne
    Morin, Roger
    InSAR as a practical tool to monitor and understand large-scale mining-induced ground deformations in a caving environment2018In: Caving 2018 / [ed] Potvin, Y. & Jakubec, J., Perth, 2018, p. 661-674Conference paper (Refereed)
  • 34.
    Sjöberg, Jonny
    et al.
    Itasca Consultants AB.
    Perman, Fredrik
    Quinteiro, Carlos
    Dahnér-Lindkvist, Christina
    Boskovic, Mirjana
    Numerical analysis of alternative mining sequences to minimise potential for fault slip rockbursting2012In: Mining Technology, ISSN 1474-9009, E-ISSN 1743-2863, no 4, p. 226-235Article in journal (Refereed)
  • 35.
    Sjöberg, Jonny
    et al.
    Itasca Consultants AB.
    Stöckel, Britt-Mari
    Mäkitaavola, Karola
    Hangingwall and footwall stability issues in sublevel caving2013In: 2013 International Symposium on Slope Stability in Open Pit Mining and Civil Engineering / [ed] P.M. Dight, Perth: Australian Centre for Geomechanics, 2013, p. 1045-1060Conference paper (Refereed)
  • 36.
    Soto, Chris
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Do Clay Minerals affect the thickener operationin Chuquicamata mine, Calama, Chile?2020Independent thesis Advanced level (degree of Master (Two Years)), 80 credits / 120 HE creditsStudent thesis
    Abstract [en]

    Chuquicamata mine mineralogy has been studied performing both X-Ray Diffraction (XRD) and X-RayFluorescence (XRF) to determine whether there is any influence in the thickener operations. Thetargeted minerals were the clay group because of their detrimental effect on mining operations asmodify the rheology of the suspensions. The operation stages most affected by the presence of the clayminerals are gravity separation, milling, conveyor belts, flotation and specially thickener operations. Inorder to cope with Chuquicamata production, the plant is constantly fed from a neighboring ore calledRadomiro Tomic (RT) ore, a secondary sulfide enrichment. At Chuquicamata, the thickener operatorfeedback has been pointed out that every time the concentrator plant is fed in high ratio with this so-called RT ore the mineral processing is hindered. For this reason, RT ore samples from a criticaloperation day were sent to Sweden for mineralogical analysis. In addition, flotation tailings from thethree Chuquicamata concentrator plants were also sent aimed to perform thickener pilot tests. In thismanner, it was seen if it could be possible to achieve new operational strategies in Chuquicamatathickener operations given the current Chuquicamata mineralogy and physical conditions in the flotationtailings.From the XRD analysis, the following clay minerals were identified in order of abundance:

                                              Illite&gt;&gt;Kaolinite&gt;SmectiteThus, illite reached up to 23.3vol% being the highest clay amount, followed by lower case kaolinite up to2.5% and up to 1% of smectite values correspond for the RT sample. However, the clay content in theflotation tailings samples were less than expected. Also, clay Crystallinity was also assessed for its abilityto interfere negatively with the pulp rheology, and the results showed that there is a strong link amongpoor crystallized smectite clay with the semi-autogenous mill compare to those samples where themilling was performed in the traditional steel media. Along with the three clay minerals found, quartz,potassic feldspar, and plagioclase were also identified, accounting for up to 76% of the representativesample. The silicate minerals are thought to be problematic in Chuquicamata thickener operations givenits high amount, especially in &lt;2 µm size.For the thickener tests, three types of polyacrylamide were used plus the current Chuquicamataflocculant. Prior to the sedimentation batch test, the rheology of the flocculants was measured in arange of 0.02%w/w to 1%. It was found that flocculant concentrations between 0.02 to 0.05%w/w themost suitable in terms of avoiding suspension rheology increase. After establishing suitable flocculantconcentrations solutions, these were used in the thickener pilot tests at conditions similar to thoseperformed in Chuquicamata thickener operations. Two criteria were used to analyze the bestsedimentation conditions: Initial settling rate (ISR); and Turbidimeter. At pH in a range of 11-12 and 15%solid, bridging flocculation probed to be the most suitable conditions for Chuquicamata thickeneroperations. Moreover, a polyacrylamide blend was tested aiming to achieve high sedimentationperformances. The flocculant blend reached both the highest initial sedimentations rate up to 48m/hand turbidity values below 20NTU at addition rate 5g/t and 7g/t. On the other hand, Chuquicamatacurrent flocculant only reached the highest values of 36m/h and turbidity of 40NTU at an addition rateof 5g/t. In this way, the current work established that conditions at Chuquicamata thickener operation

    4can be improved by understanding the absorption process among particle-polymer and mineralogy ofthe mine.Hence, the implication of this work to Chuquicamata mine is a better knowledge of its mineralogyespecially concerned with it is believed that clay minerals are not the only mineralogical factors thatcould be hindering thickener operations in Chuquicamata. Other factors that also could be problematicare: high content of silicates; clay crystallinity, particle size and mixed clay. In addition, the improvementin the thickener sedimentation operations will bring better use of the water by increasing therecirculation towards the concentrator area in a friendly way with the environment and communitiesthat also demand water in the arid region of the Atacama Desert.

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  • 37.
    Swain, Sabyasachi
    et al.
    Deltaic Regional Centre, National Institute of Hydrology, Kakinada, India.
    Mishra, Prabhash Kumar
    Climate Hydrology Division, National Institute of Hydrology, Roorkee, India.
    Nandi, Saswata
    Sierra Nevada Research Institute, University of California Merced, Merced, USA.
    Pradhan, Biswajeet
    Centre for Advanced Modelling and Geospatial Information Systems, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, Australia; Institute of Climate Change, Universiti Kebangsaan Malaysia, Bangi, Malaysia.
    Sahoo, Sashikanta
    Punjab Remote Sensing Centre, Ludhiana, 141004, India.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    A simplistic approach for monitoring meteorological drought over arid regions: a case study of Rajasthan, India2024In: Applied water science, ISSN 2190-5487, E-ISSN 2190-5495, Vol. 14, no 2, article id 36Article in journal (Refereed)
    Abstract [en]

    The commonly used precipitation-based drought indices typically rely on probability distribution functions that can be suitable when the data exhibit minimal discrepancies. However, in arid and semi-arid regions, the precipitation data often display significant discrepancies due to highly irregular rainfall patterns. Consequently, imposing any probability distributions on the data for drought analysis in such regions may not be effective. To address this issue, this study employs a novel drought index called the Discrepancy Precipitation Index (DPI), specifically designed for arid regions. Unlike traditional methods, the DPI does not impose a probability distribution on the precipitation data; instead, it relies on the discrepancy between the data and the mean value. Drought severity classifications (i.e., Drought-I, Drought-II, and Drought-III) are proposed based on the DPI values. The DPI is used to characterize and assess the meteorological drought years based on annual and monsoonal precipitation over nineteen districts in Western Rajasthan, India, during 1901–2019. Additionally, a novel statistic called Discrepancy Measure (DM) is employed to assess the degree of discrepancy in the precipitation climatology of the districts for annual and monsoon precipitation time series. Based on annual precipitation, Jaisalmer district exhibited the highest number of historical drought years (35), whereas three districts, i.e., Jhunjhunu, Dausa, and Bhilwara exhibited the lowest number of drought years (11). Similarly, based on monsoon precipitation, Jaisalmer and Bhilwara encountered the highest (34) and the lowest (11) number of drought years, respectively. The return period of Drought-II is lower for monsoon precipitation-based DPI as compared to that of the annual precipitation-based DPI for all the districts. The DM and DPI-based total number of droughts are found to be strongly correlated for both annual and monsoon precipitation. The DM value is highest for Jaisalmer and lowest for Bhilwara district. The findings reveal DPI as an efficient tool for assessing drought years, particularly in arid climatic conditions. Moreover, as the DM value increases for a precipitation series, the DPI becomes more effective in capturing drought events.

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  • 38.
    Vatcher, J
    et al.
    Itasca Consultants AB, Sweden.
    Bošković, M
    Luossavaara‐Kiirunavaara Aktiebolag (LKAB), Sweden.
    Sjöberg, J.
    Itasca Consultants AB, Sweden.
    Production-associated risk factors of seismicity in the Kiirunavaara mine2019In: Mining Geomechanical Risk 2019  / [ed] Johan Wesseloo, Luleå, 2019, p. 261-272Conference paper (Refereed)
  • 39.
    Velarde, Lisbania
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science. Department of Chemistry, Faculty of Science and Technology, San Simon University, UMSS, Cochabamba, Bolivia.
    Nabavi, Mohammad Sadegh
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Escalera, Edwin
    Department of Chemistry, Faculty of Science and Technology, San Simon University, UMSS, Cochabamba, Bolivia.
    Antti, Marta-Lena
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Akhtar, Farid
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Adsorption of heavy metals on natural zeolites: A review2023In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 328, article id 138508Article, review/survey (Refereed)
    Abstract [en]

    Water pollution has jeopardized human health, and a safe supply of drinking water has been recognized as a worldwide issue. The increase in the accumulation of heavy metals in water from different sources has led to the search for efficient and environmentally friendly treatment methods and materials for their removal. Natural zeolites are promising materials for removing heavy metals from different sources contaminating the water. It is important to know the structure, chemistry, and performance of the removal of heavy metals from water, of the natural zeolites to design water treatment processes. This review focuses on critical analyses of the application of distinct natural zeolites for the adsorption of heavy metals from water, specifically, arsenic (As(III), As(V)), cadmium (Cd(II)), chromium (Cr(III), Cr(VI)), lead (Pb(II)), mercury(Hg(II)) and nickel (Ni(II)). The reported results of heavy-metal removal by natural zeolites are summarized, and the chemical modification of natural zeolites by acid/base/salt reagent, surfactants, and metallic reagents has been analyzed, compared, and described. Furthermore, the adsorption/desorption capacity, systems, operating parameters, isotherms, and kinetics for natural zeolites were described and compared. According to the analysis, clinoptilolite is the most applied natural zeolite to remove heavy metals. It is effective in removing As, Cd, Cr, Pb, Hg, and Ni. Additionally, an interesting fact is a variation between the natural zeolites from different geological origins regarding the sorption properties and capacities for heavy metals suggesting that natural zeolites from different regions of the world are unique.

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  • 40.
    Widforss, Aron
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Avalanche Visualisation Using Satellite Radar2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Avalanche forecasters need precise knowledge about avalanche activity in large remote areas. Manual methods for gathering this data have scalability issues. Synthetic aperture radar satellites may provide much needed complementary data. This report describes Avanor, a system presenting change detection images of such satellite data in a web map client. Field validation suggests that the data in Avanor show at least 75 percent of the largest avalanches in Scandinavia with some small avalanches visible as well.

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  • 41.
    Widforss, Aron
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Teaching Machines to Recognise Avalanche Conditions2021Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Avalanche forecasting is an iterative process, where forecasters use weather data and snow observations in addition to previous assessments to conclude what forecast to publish. This project investigates how the forecasting process could be automated, using three seasons worth of data from 23 of Norway’s avalanche forecasting regions. Three scenarios were considered, using different amounts of input parameters based on what data would be available to the model in each respective scenario. For each scenario a machine learning model was trained, and a separate naïve model was constructed. The machine learning model could only beat the naïve model in the simplest scenario, using only weather data. In the other scenarios it was found that the data representation was lacking; highly intermittent snow observation data was structured as timeseries when a more preprocessed representation may have been more fruitful

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  • 42.
    Wu, Yongxiang
    et al.
    College of Resources, Environment and Materials, Guangxi University, Nanning 530004, China.
    Nhung, Nguyen Thi Hong
    College of Resources, Environment and Materials, Guangxi University, Nanning 530004, China.
    Zeng, Deqian
    College of Resources, Environment and Materials, Guangxi University, Nanning 530004, China.
    Luo, Nengneng
    College of Resources, Environment and Materials, Guangxi University, Nanning 530004, China.
    Otsuki, Akira
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering. Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez, Diagonal Las Torres 2640, 11 Peñalolén, Santiago 7941169, Chile.
    Dodbiba, Gjergj
    Graduate School of Engineering, The University of Tokyo, Tokyo 113-8656, Japan.
    Fujita, Toyohisa
    College of Resources, Environment and Materials, Guangxi University, Nanning 530004, China.
    Flower-like vaterite produced by nanobubble-containing ethanol and water mixed solution for Cd (II) removal2024In: Advanced Powder Technology, ISSN 0921-8831, E-ISSN 1568-5527, Vol. 35, no 1, article id 104279Article in journal (Refereed)
1 - 42 of 42
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