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  • 1.
    Ahmad, Arslan
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. Brabant Water NV, 5200 BC 's-Hertogenbosch, The Netherlands.
    Evaluation and optimization of advanced oxidation coagulation filtration (AOCF) to produce drinking water with less than 1 μg/L of arsenic2014Report (Other academic)
    Abstract [en]

    Arsenic is an extremely poisonous element. It has been reported to cause contamination of drinking water sources in many parts of the world. The current drinking water permissible limit for arsenic in the European Union is 10 μg/L. The World Health Organization has a general rule that no substance may have a higher lifetime risk of more than 1 in 100,000. However, several studies on toxicity of arsenic suggest that purely based on health effects the arsenic limit of 10 μg/L is not sufficient. The main goal of this research was to develop an efficient arsenic removal technology that could be able to produce drinking water with an arsenic concentration of less than 1 μg/L. For this purpose, an innovative three step technique, Advanced Oxidation - Coagulation - Filtration (AOCF), was investigated through bench-scale and pilot scale experiments in the Netherlands at the water treatment plant of Dorst. Firstly, prior to the investigations on AOCF, the existing arsenic removal at the water treatment plant was investigated. Secondly, through a series of bench-scale experiments, the optimum type of coagulant, its combination dose with the selected chemical oxidant and optimum process pH were determined. Eventually, the partially optimized technique from the bench-scale was implemented at the pilot scale physical model of water treatment plant Dorst where AOCF was evaluated for arsenic removal and its effect on the removal of other common undesirable groundwater constituents. The optimized AOCF technology consistently removed arsenic from groundwater to below 1 ug/L when implemented at pilot scale. The overall effluent quality also remained acceptable. The method is efficient with both types of filtration media tested in this research i.e., virgin sand and metal oxide coated sand, however virgin sand media showed slightly better arsenic removal efficiency.

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    TRITA-LWR Report 2014-1_AOCF
  • 2.
    Aid, Graham
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Brandt, Nils
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Action Research In Waste Management: Application to construction and demolition waste in the Stockholm region2010In: Linnaeus ECO-TECH ´10 / [ed] Fabio Kaczala, Linnaeus University , 2010, p. 1009-1019Conference paper (Refereed)
    Abstract [en]

    The action research methodology and several of its methods have previously been highlighted and described by the authors as a fitting and rigorous framework approach for complex waste management systems.  This was in response to criticism of the ex ante selection of traditional empiric systems analysis tools to provide decision support and ‘sustainable improvement’ in such complex systems which often involve strong human and political factors.   Several of the action research methods described have recently been utilized in a case study around mineral (aggregate) construction and demolition waste in the Stockholm region.  These methods were integrated through a series of workshops and work areas undergone together with project members from several private and public sectors.  Leaving the problem fuzzy (loosely defined) in the beginning; utilizing convergent interviewing, rich pictures and focus groups allowed the researchers and partner stakeholders to identify not one but several problem areas within the system of focus.  Indicator creation and a dialectic processes were then used to identify qualitative and quantitative aspects of salience around these problem areas.  These resulting indicators were strengthened through a process of verification.  Each indicator was then analyzed by what was deemed to be appropriate and transparent means.  It is argued that this approach may create better communication, transparency, and understanding by the stakeholders.  These factors in turn allowing stronger stakeholder ownership of the process and assisting in more informed decisions and help to provide stability for desired change. However the process was not without its drawbacks such as intense communication and time requirements.

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    Action Research for Waste Management
  • 3.
    Bergsjö, Joline
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Geoinformatics.
    Object based change detection in urban area using KTH-SEG2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today more and more people are moving to the cities around the world. This puts a lot of strain on the infrastructure as the cities grow in both width and height. To be able to monitor the ongoing change remote sensing is an effective tool and ways to make it even more effective, better and easier to use are constantly sought after.

    One way to monitor change detection is object based change detection. The idea has been around since the seventies, but it wasn’t until the early 2000 when it was introduced by Blaschke and Strobl(2001) to the market as a solution to the issues with pixel based analysis that it became popular with remote analysts around the world.

    KTH-SEG is developed at KTH Geoinformatics. It is developed to segment images in order to preform object based analysis; it can also be used for classification.

    In this thesis object based change detection over an area of Shanghai is carried out. Two different approaches are used; post-classification analysis as well as creating change detection images. The maps are assessed using the maximum likelihood report in the software Geomatica.

    The segmentation and classification is done using KTH-SEG, training areas and ground truth data polygons are drawn in ArcGIS and pre-processing and other operations is carried out using Geomatica.

    KTH-SEG offers a number of changeable settings that allows the segmentation to suit the image at hand.  It is easy to use and produces well defined classification maps that are usable for change detection

    The results are evaluated in order to estimate the efficiency of object based change detection in urban area and KTH-SEG is appraised as a segmentation and classification tool.

    The results show that the post-classification approach is superior to the change detection images. Whether the poor result of the change detection images is affected by other parameters than the object based approach can’t be determined. 

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    Bergsjö 2014 KEX
  • 4. Bin, Ma
    et al.
    Gubanski, Stanislaw M.
    Krivda, Andrej
    Schmidt, Lars. E.
    Hollertz, Rebecca
    ABB Corporate Research, Dättwil, Switzerland .
    Dielectric Properties and Resistance to Corona and Ozone of Epoxy Compositions Filled with Micro- and Nano-fillers2009In: Annual Report - Conference on Electrical Insulation and Dielectric Phenomena, 2009, p. -380Conference paper (Refereed)
    Abstract [en]

    This paper describes activities aiming to evaluate and compare the resistance to a prolonged corona and ozone exposure for a range of epoxy based compositions filled with micro- and nano-fillers of silica at different proportions. It has been earlier shown for this system that substitution of 5 wt% of micro-filler by nano-filler slightly improved mechanical properties, yielding an increase in Young's modulus, tensile strength and elongation at break. At the same time, the toughness of the systems decreased with the addition of nano-fillers indicating a poor particle-matrix interaction, which was in accordance with the prior art claiming that this interaction is weaker in case of SiO 2 nano-particles, as for example compared to Al 2O 3 nano-particles. For the exposure to corona and ozone a methodology employing a multiple-needle electrode system was used, as recommended by CIGRE working group WG D1.14. Measurements of surface resistivity, bulk resistivity as well as dielectric response (DR) at broad frequency range (10 -4-10 3 Hz) were performed on new samples of the investigated compositions and after each of two sequences of the corona-ozone treatment, lasting 100hours each. It was found that the long-term corona-ozone exposure had obvious effect on surface resistivity for all the compositions investigated and the contents of the micro- and nano-fillers played a significant role in the observed changes. On the other hand, bulk resisitivity, dielectric permittivity as well as dissipation factor, all being the properties of material bulk, did not exhibit high sensitivity to the exposure.

  • 5.
    Broberg, Josephine
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Ericson, Molly
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Frid, Gustav
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Biofuel: - Sustainability of the Jatropha cultivation in Zambia2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
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  • 6.
    Calil Kores, Cristine
    et al.
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Ismail, Nur
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Geskus, Dimitri
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Dijkstra, M.
    Bernhardi, Edward H.
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Pollnau, Markus
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Temperature dependence of the resonance line of optically pumped distributed-feedback lasers2018In: Optics InfoBase Conference Papers, OSA - The Optical Society , 2018Conference paper (Refereed)
    Abstract [en]

    We characterize experimentally and theoretically a distributed-feedback laser resonator subject to a thermal chirp. The total accumulated phase shift determines the resonance wavelength. The reflectivities (outcoupling losses) at the resonance wavelength govern the resonance linewidth.

  • 7. Echternach, Matthias
    et al.
    Burk, Fabian
    Koeberlein, Marie
    Selamtzis, Andreas
    KTH, School of Computer Science and Communication (CSC), Speech, Music and Hearing, TMH.
    Doellinger, Michael
    Burdumy, Michael
    Richter, Bernhard
    Herbst, Christian Thomas
    Laryngeal evidence for the first and second passaggio in professionally trained sopranos2017In: PLOS ONE, E-ISSN 1932-6203, Vol. 12, no 5, article id e0175865Article in journal (Refereed)
    Abstract [en]

    Introduction Due to a lack of empirical data, the current understanding of the laryngeal mechanics in the passaggio regions (i.e., the fundamental frequency ranges where vocal registration events usually occur) of the female singing voice is still limited. Material and methods In this study the first and second passaggio regions of 10 professionally trained female classical soprano singers were analyzed. The sopranos performed pitch glides from A3 (f(o) = 220 Hz) to A4 (f(o) = 440 Hz) and from A4 (f(o) = 440 Hz) to A5 (f(o) = 880 Hz) on the vowel [i:]. Vocal fold vibration was assessed with trans-nasal high speed videoendoscopy at 20,000 fps, complemented by simultaneous electroglottographic (EGG) and acoustic recordings. Register breaks were perceptually rated by 12 voice experts. Voice stability was documented with the EGG-based sample entropy. Glottal opening and closing patterns during the passaggi were analyzed, supplemented with open quotient data extracted from the glottal area waveform. Results In both the first and the second passaggio, variations of vocal fold vibration patterns were found. Four distinct patterns emerged: smooth transitions with either increasing or decreasing durations of glottal closure, abrupt register transitions, and intermediate loss of vocal fold contact. Audible register transitions (in both the first and second passaggi) generally coincided with higher sample entropy values and higher open quotient variance through the respective passaggi. Conclusions Noteworthy vocal fold oscillatory registration events occur in both the first and the second passaggio even in professional sopranos. The respective transitions are hypothesized to be caused by either (a) a change of laryngeal biomechanical properties; or by (b) vocal tract resonance effects, constituting level 2 source-filter interactions.

  • 8. Fabiani, D.
    et al.
    Montanari, G.C.
    Krivda, A.
    Schmidt, L.E.
    Hollertz, Rebecca
    ABB Switzerland Ltd., Switzerland .
    Epoxy based materials containing micro and nano sized fillers for improved electrical characteristics2010In: Proceedings of the 2010 IEEE International Conference on Solid Dielectrics, ICSD 2010, 2010Conference paper (Refereed)
    Abstract [en]

    In this paper the effect on dc and ac electrical properties of silica nano and micro particles dispersed in epoxy resins is discussed. In particular, space charge, conductivity, dielectric strength and partial discharge resistance is analyzed. The results show that nanostructured materials exhibit smaller space charge accumulation with respect to both base and microfilled materials. Regarding PD resistance, micro + nano filled materials display longer lifetimes with respect to base epoxy resin and materials including nanofillers or microfillers alone.

  • 9.
    Frickner, Elvira
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Urban and Regional Studies.
    Naturvård i den urbana miljön: En studie kring naturvård med häst i en tid av urban förtätning2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In urban planning, there is currently a challenge with keeping the balance between the urban city and the surrounding nature, especially as the population grows and with it the need of cities with high densities. The increasing awareness of the functions that the urban greenspaces provide is important as ecosystem services are planned as resources for the city on a very limited area. To be able to conserve and develop the values and ecosystem services provided by nature it needs to be taken care of in a suitable way. The aim of this study is to investigate urban nature conservation methods with the use horses and what values these methods provide. Also, the conditions for ecosystem services and green values created by nature conservation are investigated. The methods used are a literature study as well as a case study consisting of interviews and a document study.

     

    The conclusion made from the study is that nature provides many values, both ecologic, social and economic, and these values are in need of proper nature conservation to be able to persist and develop in the future. Nature conservation with horses is an effective way to manage nature and maintain and develop values and services in the future. It also provides social and pedagogical values as the horses are appreciated by people and they stimulate learning and taking in new knowledge, especially about nature and ecosystem services. Nature conservation with horses seems more expensive than other methods, depending on the service executed by hired contractor. The gains in the many conserved values are however considered higher than the costs. There are many values that can be acquired by integrating the use of horses in nature conservation, either as a whole or partial.

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  • 10.
    Frid, Emma
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Human Centered Technology, Media Technology and Interaction Design, MID.
    Bresin, Roberto
    KTH, School of Electrical Engineering and Computer Science (EECS), Human Centered Technology, Media Technology and Interaction Design, MID.
    Sallnäs Pysander, Eva-Lotta
    KTH, School of Electrical Engineering and Computer Science (EECS), Human Centered Technology, Media Technology and Interaction Design, MID.
    Moll, Jonas
    Uppsala University.
    An Exploratory Study On The Effect Of Auditory Feedback On Gaze Behavior In a Virtual Throwing Task With and Without Haptic Feedback2017In: Proceedings of the 14th Sound and Music Computing Conference / [ed] Tapio Lokki, Jukka Pätynen, and Vesa Välimäki, Espoo, Finland, 2017, p. 242-249Conference paper (Refereed)
    Abstract [en]

    This paper presents findings from an exploratory study on the effect of auditory feedback on gaze behavior. A total of 20 participants took part in an experiment where the task was to throw a virtual ball into a goal in different conditions: visual only, audiovisual, visuohaptic and audio- visuohaptic. Two different sound models were compared in the audio conditions. Analysis of eye tracking metrics indicated large inter-subject variability; difference between subjects was greater than difference between feedback conditions. No significant effect of condition could be observed, but clusters of similar behaviors were identified. Some of the participants’ gaze behaviors appeared to have been affected by the presence of auditory feedback, but the effect of sound model was not consistent across subjects. We discuss individual behaviors and illustrate gaze behavior through sonification of gaze trajectories. Findings from this study raise intriguing questions that motivate future large-scale studies on the effect of auditory feedback on gaze behavior. 

  • 11.
    Frid, Emma
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Human Centered Technology, Media Technology and Interaction Design, MID.
    Elblaus, Ludvig
    KTH, School of Electrical Engineering and Computer Science (EECS), Human Centered Technology, Media Technology and Interaction Design, MID.
    Bresin, Roberto
    KTH, School of Electrical Engineering and Computer Science (EECS), Human Centered Technology, Media Technology and Interaction Design, MID.
    Interactive sonification of a fluid dance movement: an exploratory study2019In: Journal on Multimodal User Interfaces, ISSN 1783-7677, E-ISSN 1783-8738, Vol. 13, no 3, p. 181-189Article in journal (Refereed)
    Abstract [en]

    In this paper we present three different experiments designed to explore sound properties associated with fluid movement: (1) an experiment in which participants adjusted parameters of a sonification model developed for a fluid dance movement, (2) a vocal sketching experiment in which participants sketched sounds portraying fluid versus nonfluid movements, and (3) a workshop in which participants discussed and selected fluid versus nonfluid sounds. Consistent findings from the three experiments indicated that sounds expressing fluidity generally occupy a lower register and has less high frequency content, as well as a lower bandwidth, than sounds expressing nonfluidity. The ideal sound to express fluidity is continuous, calm, slow, pitched, reminiscent of wind, water or an acoustic musical instrument. The ideal sound to express nonfluidity is harsh, non-continuous, abrupt, dissonant, conceptually associated with metal or wood, unhuman and robotic. Findings presented in this paper can be used as design guidelines for future applications in which the movement property fluidity is to be conveyed through sonification.

  • 12.
    Fryers Hellquist, Katharina
    Stockholms universitet, Stockholm Resilience Centre.
    Exploring Change Agents in Watershed Governance: The Case of Lake Mälaren, Sweden.2016Independent thesis Advanced level (degree of Master (Two Years)), 40 credits / 60 HE creditsStudent thesis
    Abstract [en]

    The world is changing rapidly and it has become increasingly important to build resilience, through adaptation and transformation, to maintain the ecosystem services that watersheds provide. The importance of change agents to prepare for and navigate the transformation, as well as build resilience in the new state has been highlighted by scholars, however not in a comprehensive way, but rather as a final conclusion. This study investigates the role and perceptions of change agents around Lake Mälaren, Sweden. Through in-depth interviews, it explores incentives for change, visions, and strategies to reach those visions. The findings show that many actors without holistic and overarching governance creates dissatisfaction among change agent. Components of their visions are shared: well-functioning ecosystems that provide ecosystem services in the future, and to achieve legislated goals. Their strategy on how to reach their vision diverge: powerful political decisions and stricter steering, or changes in values and the inclusion of local knowledge of citizens. This study adds nuance to visions, highlights the importance of a common strategy and that collaboration is key to maintain the future provision of the essential ecosystem services watersheds provide.

  • 13. Gejo, T.
    et al.
    Oura, M.
    Tokushima, T.
    Horikawa, Y.
    Arai, H.
    Shin, S.
    Kimberg, Victor
    KTH, School of Biotechnology (BIO), Theoretical Chemistry and Biology.
    Kosugi, N.
    Resonant inelastic x-ray scattering and photoemission measurement of O2: Direct evidence for dependence of Rydberg-valence mixing on vibrational states in O 1 s → Rydberg states2017In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 147, no 4, article id 044310Article in journal (Refereed)
    Abstract [en]

    High-resolution resonant inelastic x-ray scattering (RIXS) and low-energy photoemission spectra of oxygen molecules have been measured for investigating the electronic structure of Rydberg states in the O 1s → σ∗ energy region. The electronic characteristics of each Rydberg state have been successfully observed, and new assignments are made for several states. The RIXS spectra clearly show that vibrational excitation is very sensitive to the electronic characteristics because of Rydberg-valence mixing and vibronic coupling in O2. This observation constitutes direct experimental evidence that the Rydberg-valence mixing characteristic depends on the vibrational excitation near the avoided crossing of potential surfaces. We also measured the photoemission spectra of metastable oxygen atoms (O) from O2 excited to 1s → Rydberg states. The broadening of the 4p Rydberg states of O∗ has been found with isotropic behavior, implying that excited oxygen molecules undergo dissociation with a lifetime of the order of 10 fs in 1s → Rydberg states.

  • 14.
    Ghazi Moradi, Farnaz
    et al.
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Cederwall, Bo
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Qi, Chong
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Ataç, Ayşe
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Liotta, Roberto
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Doncel, Maria
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Johnson, Arne
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    et al.,
    Spectroscopy of the neutron deficient N=50 nucleus 95Rh2014Manuscript (preprint) (Other academic)
  • 15.
    Giummarella, Nicola
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Balakshin, Mikhail
    Koutaniemi, Sanna
    Kärkönen, Anna
    Lawoko, Martin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Nativity of lignin carbohydrate bonds substantiated by biomimetic synthesis2019In: Journal of Experimental Botany, ISSN 0022-0957, E-ISSN 1460-2431, Vol. 70, no 20, p. 5591-5601Article in journal (Refereed)
    Abstract [en]

    The question of whether lignin is covalently linked to carbohydrates in native wood, forming what is referred to as lignin–carbohydrate complexes (LCCs), still lacks unequivocal proof. This is mainly due to the need to isolate lignin from woody materials prior to analysis, under conditions leading to partial chemical modification of the native wood polymers. Thus, the correlation between the structure of the isolated LCCs and LCCs in situ remains open. As a way to circumvent the problematic isolation, biomimicking lignin polymerization in vivo and in vitro is an interesting option. Herein, we report the detection of lignin–carbohydrate bonds in the extracellular lignin formed by tissue-cultured Norway spruce cells, and in modified biomimetic lignin synthesis (dehydrogenation polymers). Semi-quantitative 2D heteronuclear singular quantum coherence (HSQC)-, 31P -, and 13C-NMR spectroscopy were applied as analytical tools. Combining results from these systems, four types of lignin–carbohydrate bonds were detected; benzyl ether, benzyl ester, γ-ester, and phenyl glycoside linkages, providing direct evidence of lignin–carbohydrate bond formation in biomimicked lignin polymerization. Based on our findings, we propose a sequence for lignin–carbohydrate bond formation in plant cell walls.

  • 16.
    Hallström, Jonas
    et al.
    Technology and Science Education Research (TESER), Department of Behavioural Sciences and Learning (IBL), Linköping University, 601 74, Norrköping, Sweden.
    Norström, Per
    KTH, School of Industrial Engineering and Management (ITM), Learning, Learning in Stem.
    Schönborn, Konrad J.
    Division of Media and Information Technology, Department of Science and Technology (ITN), Linköping University, 601 74, Norrköping, Sweden.
    Authentic STEM education through modelling: An international Delphi study2023In: International Journal of STEM education, E-ISSN 2196-7822, Vol. 10, no 1, article id 62Article in journal (Refereed)
    Abstract [en]

    The literature asserts that science, technology, engineering, and mathematics (STEM) education needs to be authentic. Although models and modelling provide a basis from which to increase authenticity by bridging the STEM disciplines, the idea of authentic STEM education remains challenging to define. In response, the aim of this study is to identify consensus on significant elements of authentic STEM education through models and modelling. Views were gathered anonymously over three rounds of questions with an expert panel. Responses were subjected to a multimethod analysis that pursued identification, consensus, and stability in the panel’s revealed propositions and themes around authentic STEM education through modelling.

    The panel reached high consensus concerning the potential of STEM education to support learning across traditional subject borders through authentic problem solving. The panel also consented that modelling is indispensable for achieving real-world relevance in STEM education, and that model-based integrated STEM education approaches provide opportunities for authentic problem solving. Furthermore, results showed that integrating individual STEM subjects during teaching, in terms of including disciplinary knowledge and skills, requires specialised competence. Here, technology and engineering subjects tended to implicitly underpin communicated teaching activities aimed at STEM integration.

    The panellists stress that STEM disciplines should be taught collaboratively at the same time as they are not in favour of STEM as a subject of its own but rather as a cooperation that maintains the integrity of each individual subject. Many respondents mentioned integrated STEM projects that included modelling and engineering design, although they were not specifically labelled as engineering projects. Thus, real-world STEM education scenarios are often viewed as being primarily technology and engineering based. The panel responses also implicate a need for multiple definitions of authenticity for different educational levels because a great deal of uncertainty surrounding authenticity seems to originate from the concept implying different meanings for different STEM audiences. These international Delphi findings can potentially inform integrated STEM classroom interventions, teacher education development, educational resource and curriculum design.

  • 17.
    Hemlin, Hanna
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Lalangas, Nektaria
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Production of Biochar Through Slow Pyrolysis of Biomass: Peat,Straw, Horse Manure and Sewage Sludge2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    With a growing concern of climate change due to increased levels of CO2 in the atmosphere, carbon sequestration has been suggested as a possible solution for climate change mitigation. Biochar,a highly carbonaceous product produced through pyrolysis, is considered a viable option due to its content of stable carbon. This work covers the investigation of the possibility to produce biocharfrom four different feedstocks, namely peat, straw, horse manure and sewage sludge. The study includes a literature study and a five-week trial period at a 500 kW pilot plant, PYREG 500, in Högdalen. The thermal behaviour of the feedstocks, including garden waste, was investigated using thermogravimetric analysis (TGA). The TGA results were used to decide the optimal pyrolysis temperature for peat and straw at the pilot plant. The TGA results showed that the feedstocks behave differently when pyrolysed; the mass loss rate as well as the final mass loss varied. Physiochemical characterisation of the biochar was completed and the results were in agreement with previous studies. The produced biochar from straw and two types of peat had a C content above50 wt.% (76.6, 80.7, 79.2 wt.%) and low molar ratios of H/C (0.33, 0.36, 0.38) and O/C (0.032,0.023, 0.024). The pH increased as a consequence of pyrolysis and the biochars were alkaline (pH10.1, 8.5, 8.3). Polycyclic aromatic hydrocarbons (PAHs) were found in biochar from both strawand peat (8.26, 1.03, 5.83 mg/kg). In general, nutrients and heavy metals were concentrated in the biochar, except for Cd which decreased and Hg which could not be determined. The specific surface area of biochar from straw was considered small (21 m2/g) while biochar from peat had a higher specific surface area with a greater span (102-247 m2/g). The properties of the produced biochar were compared to the criteria included in the European Biochar Certificate and some of them were fulfilled, including the content of C, PAH and heavy metals. A flue gas analysis was completed when operating the pilot plant on straw pellets and it was showed that several emissions were released, including NO2, SOX, HCl and particulates, however, solely the emissions of NO2 exceed the regulations which will be applied in 2020. Regarding process design of a future pyrolysis plant, it is suggested that the means of material transport, particle separation, temperature control and quenching of biochar should be improved.

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    fulltext
  • 18.
    Jacob, Alexander
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Geoinformatics.
    Ban, Yifang
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Geoinformatics.
    Segmentation of multi-temporal envisat asar and hj-1b optical data using an edge-aware region growing and merging algorithm2013In: European Space Agency, (Special Publication) ESA SP, Volume 704 SP, 2013, 2013Conference paper (Refereed)
    Abstract [en]

    The paper aims to develop image segmentation algorithms for classification of multi-sensor data in urban areas. For this purpose an algorithm called KTHSEG has been developed using an edge-aware region growing and merging algorithm. Four-date ENVISAT ASAR C-HH data and one-date HJ-1B covering the city of Shanghai acquired during the vegetation season of 2009 were selected this research. The results show that the segmentation algorithm is effective for urban land cover classification using SAR and optical data. The results also confirm that the fusion of SAR and optical data is beneficial for urban land cover mapping. Further, the study showed that the combination of one SAR and one optical scene is enough to achieve good results and the addition of multitemporal SAR data from the same beam mode does not improve classification accuracy.

  • 19.
    Johansson, Mats
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Hedlund, Hans Peter
    Prototypes of Lascaux´s medium for consolidation2005In: Restauro: Zeitschrift für Kunsttechniken, ISSN 0933-4017, Vol. 6, p. 432-439Article in journal (Refereed)
  • 20.
    Kolmskog, Peter
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Physical Metallurgy.
    Borgenstam, Annika
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Physical Metallurgy.
    Hillert, Mats
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering.
    Hedström, Peter
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Physical Metallurgy.
    Babu, Sudarsanam Suresh
    Terasaki, Hidenori
    Komizo, Yu-Ichi
    Direct Observation that Bainite can Grow Below M-S2012In: Metallurgical and Materials Transactions. A, ISSN 1073-5623, E-ISSN 1543-1940, Vol. 43A, no 13, p. 4984-4988Article in journal (Refereed)
    Abstract [en]

    In situ simultaneous synchrotron X-ray diffraction and laser scanning confocal microscopy have confirmed that bainite in steels can grow below the martensite start temperature. This observation suggests that the formation curves for bainite in time-temperature-transformation diagrams should be extended below the martensite start temperature. Furthermore, the implication of this observation on the growth mechanism of bainitic ferrite is discussed.

  • 21. Kozlov, Alexander
    et al.
    Matrosov, Valerij
    National Research Lobachevsky State University of Nizhny Novgorod, Russian Federatio.
    Shalfeev, Vladimir
    National Research Lobachevsky State University of Nizhny Novgorod, Russian Federatio.
    About dynamics of publication activity on synchronization2022In: Izvestiya VUZ. Applied Nonlinear Dynamics, ISSN 0869-6632Article in journal (Refereed)
    Abstract [en]

    Purpose of the work is to research of the world science publications dynamics on the synchronization. Methods. The research methods are the statistical methods of data processing. Results. The emphasis in the study of synchronization over the past twenty years has shifted from physical and technical sciences to neuroscience with Asian countries domination.

  • 22.
    Kroon, Martin
    et al.
    KTH, School of Engineering Sciences (SCI), Solid Mechanics (Dept.).
    Holzapfel, Gerhard A.
    KTH, School of Engineering Sciences (SCI), Solid Mechanics (Dept.).
    A theoretical model for saccular cerebral aneurysm growth: Deformation and stress-analysis2007In: Proceedings of the ASME Summer Bioengineering Conference 2007, 2007, p. 255-256Conference paper (Refereed)
  • 23.
    Li, Hong-bao
    et al.
    KTH, School of Biotechnology (BIO), Theoretical Chemistry and Biology.
    Lin, Zi-jing
    Luo, Yi
    KTH, School of Biotechnology (BIO), Theoretical Chemistry and Biology.
    Local Structures and Chemical Properties of Deprotonated Arginine2012In: Chinese Journal of Chemical Physics, ISSN 1674-0068, Vol. 25, no 6, p. 681-686Article in journal (Refereed)
    Abstract [en]

    The potential energy surface of gaseous deprotonated arginine has been systematically investigated by first principles calculations. At the B3LYP/6-31G(d) level, apart from the identification of several stable local structures, a new global minimum is located which is about 6.56 kJ/mol more stable than what has been reported. The deprotonated arginine molecule has two distinct forms with the deprotonation at the carboxylate group (COO-). These two forms are bridged by very high energy barrier and possess very different IR spectral profiles. Our calculated proton dissociation energy and gas-phase acidity of arginine molecule are found to be in good agreement with the corresponding experimental results. The predicted geometries, dipole moments, rotational constants, vertical ionization energies and IR spectra of low energy conformers will be useful for future experimental measurements.

  • 24.
    Liljenström, Carolina
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Sustainability Assessment and Management.
    Life cycle assessment in early planning of transport systems: Decision support at project and network levels2018Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The Swedish Climate Policy Framework implies that the Swedish transport sector must reduce its greenhouse gas emissions to nearly zero by 2045. Previous studies have – using life cycle assessment – shown that indirect greenhouse gas emissions from the vehicle and infrastructure life cycle are significant and should be considered in transport policy and planning of transport systems, in addition to direct emissions of vehicle operation.

    The aim of this thesis is to contribute with knowledge on climate impact and primary energy use of transport systems for decision-support in early planning at project and network levels, and evaluate and demonstrate how life cycle climate impact and primary energy use can be assessed in early planning. This thesis includes three papers that contribute to achieving this aim. Paper I developed a methodological approach to assess annual climate impact and primary energy use of Swedish road, rail, air, and sea transport infrastructure at a network level. Paper II then expanded this system to the assessment of the Swedish transport system at a network level, including national and international freight and passenger transport by road, rail, air, and sea. At the project level, Paper III examined how LCA can be used as decision-support in choice of road corridor, considering the practical prerequisite of data availability in early planning and usefulness of results in the decision-making process.

    Paper I showed that the annual climate impact of Swedish transport infrastructure is around 3 million tonnes CO2 equivalents and that the annual primary energy use is around 27 TWh. Road infrastructure accounted for the largest proportion of impacts – around 70% of the climate impact and around 80% of the energy use. Paper II showed that the annual climate impact of the Swedish transport system was around 44 million tonnes CO2 equivalents and the primary energy use was around 178 TWh. Road transport and aviation together accounted for 90% of the climate impact and primary energy use. Indirect impacts were significant, especially for road and rail transport, accounting for 30% of the total climate impact and primary energy use. Paper III found that (1) collection of project specific data should focus on parameters that differentiate the road corridors, that can be influenced in early planning, and that are not directly related to the road length and (2) life cycle assessment based models used in early planning should include nation specific generic data approved by the national road authority. 

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    Liljenström
  • 25.
    Liljenström, Carolina
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Sustainability Assessment and Management.
    Life cycle assessment of transport systems and transport infrastructure: Investigating methodological approaches and quantifying impacts at project and network levels2021Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Reducing greenhouse gas emissions from the transport sector is a key challenge to reach global climate targets and limit global warming to below 2 ºC. The use of life cycle assessment (LCA) may provide knowledge about the environmental impacts of transport systems so that emission reduction measures can be identified.

    The aim of this thesis is to investigate how LCA can contribute with knowledge that can be used to support specific decisions in the context of transport system policy and planning, to demonstrate how LCA can be conducted at project and network levels, and to contribute with knowledge of direct and indirect climate impact and primary energy use of the Swedish transport infrastructure and the Swedish transport system at a network level.

    The thesis includes four papers that contribute to achieving this aim. Paper 1 demonstrates an approach for the identification of hotspots in Swedish road, rail, air, and sea transport infrastructure at a network level. Paper 2 demonstrates this approach for the full transport system at a network level, including national and international freight transport and passenger travel by road, rail, air, and sea. At the project level, Paper 3 investigates how LCA can be used as decision-support in choice of road corridor, considering prerequisites of data availability and usefulness of results for decision-making. Paper 4 maps approaches used to quantify impacts of the maintenance stage in 92 project-level LCAs of road and rail infrastructure and discusses their applicability in policy and procurement.

    Paper 1 estimated that the annual climate impact of Swedish transport infrastructure is about 3 Mtonne CO2 equivalents and that the corresponding primary energy use is about 27 TWh. Road and rail infrastructure contributed to 90% of these impacts. Additional hotspots identified were reinvestment of roads and railways and production of asphalt, concrete, and steel. Paper 2 estimated that the annual climate impact of the Swedish transport system is about 40 Mtonne CO2 equivalents and that the corresponding primary energy use is about 196 TWh. Road transport and aviation together accounted for 85% of these impacts. Indirect impacts were significant, accounting for about a third of the impacts. The main causes of indirect impacts were fuel production for road passenger travel and manufacturing of passenger cars.

    Paper 3 found that LCA-based models used in early planning should include generic data that are nation specific (preferably approved by the national road authority) and that can be replaced by project specific data when needed. Further, both traffic and infrastructure should be included at a level of detail that allows the identification of improvement measures and the assessment of uncertainty in the results. Results should be presented relative to a reference alternative and complement results from other decision-support used in planning. Paper 4 found a variety of approaches to quantify impacts of the maintenance stage in LCA. The analysis period was often determined based on the infrastructure’s service life. The maintenance frequency was commonly estimated based on the current practice of maintenance in a region or on performance prediction modelling. Only two of the reviewed papers included the effects of climate change on results of the LCA. How the approaches can be implemented in decision-making depends on their abilities to be standardised for use in procurement and to incorporate multiple scenarios.

    Stakeholders involved in transport system policy and planning can use these results as support in considering life cycle impacts in their decision-making practice to reduce environmental impacts in line with national and international targets.

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  • 26.
    Liljenström, Carolina
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Sustainability Assessment and Management.
    Miliutenko, Sofiia
    IVL Swedish Environmental Research Institute.
    O'Born, Reyn
    University of Agder, Norway.
    Brattebo, Helge
    Norweigian University of Science and Technology.
    Birgisdottir, Harpa
    Danish Building Research Institute, Aalborg University, Denmark.
    Toller, Susanna
    The Swedish Transport Administration.
    Lundberg, Kristina
    Ecoloop, Stockholm, Sweden.
    Potting, José
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Sustainability Assessment and Management.
    Life cycle assessment as decision-support in choice of road corridor: case study and stakeholder perspectivesManuscript (preprint) (Other academic)
    Abstract [en]

    The possibilities to influence environmental impacts during the road life cycle are greatest in early planning; however, the lack of project specific data makes it difficult to use life cycle assessment as decision-support. This paper examines how life cycle assessment can be used to support the choice of road corridor, considering the practical prerequisit of simplicity and usefulness of results for decision-making. The model LICCER was used to quantify life cycle impacts of road corridors in a construction project in Sweden. Availability of input data and usefulness of results was discussed with road authorities in Sweden, Norway, and Denmark. Traffic operation contributed most to life cycle impacts in all road corridors, thus the shortest construction alternative had the lowest life cycle impacts. However, the shortest alternative had the highest infrastructure related impacts due to large quantities of earthworks. Parameters that had the highest influence on results were those that affected the impacts of traffic, earthworks, and pavement. While workshop participants agreed that project specific data are scarce and uncertain in early planning, they also believed that planners can make satisfactory estimations and that the model output is useful to support the choice of road corridor. To balance simplicity and usefulness of results, data collection should focus on parameters that have high contribution to environmental impacts, that differentiate the road corridors, and are not proportional to the road length. To implement life cycle assessment in practice, models should preferably include nation specific data approved by the national road authority.

  • 27.
    Liljenström, Carolina
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Sustainability Assessment and Management.
    Toller, Susanna
    The Swedish Transport Administration.
    Åkerman, Jonas
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Strategic Sustainability Studies.
    Björklund, Anna
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Sustainability Assessment and Management. KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment.
    Annual climate impact and primary energy use of Swedish transport infrastructureManuscript (preprint) (Other academic)
    Abstract [en]

    By 2045, Sweden is to have zero net emissions of greenhouse gases, implying that also the transport sector must reduce its emissions to nearly zero by that year. Planning for emission reduction measures require network level studies showing environmental impacts of the transport network. Previous studies do not allow assessment of current hotspots in the infrastructure network, which limits their relevance for decision-support in this question. The aim of this paper is to assess the current annual climate impact and primary energy use of Swedish transport infrastructure by using a methodological approach based on life cycle assessment. The scope includes new construction and management of roads, railways, airports, ports, and fairway channels. The climate impact was estimated to 3 million tonnes carbon dioxide equivalents and the primary energy use was estimated to 27 terawatt hours. Mainly road and rail infrastructure contributed to these impacts. The environmental hotspots in the infrastructure network were identified as management of the infrastructure stock (particularly reinvestment of road and rail infrastructure) and material production (particularly production of asphalt, steel, and concrete). Planners should work systematically with emission and energy efficiency in these areas to reduce impacts of Swedish transport infrastructure. Additional research on impacts of small construction measures, the size of biogenic carbon emissions (in standing biomass as well as soil carbon), and the use and impacts of asphalt used in road construction and management would further increase the understanding of Swedish transport infrastructure at the network level.

  • 28.
    Liljenström, Carolina
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Sustainability Assessment and Management.
    Åkerman, Jonas
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Strategic Sustainability Studies.
    Björklund, Anna
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Sustainability Assessment and Management. KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment.
    Toller, Susanna
    The Swedish Transport Administration.
    Direct and indirect climate impact and primary energy use of the Swedish transport systemManuscript (preprint) (Other academic)
  • 29.
    Lin, Lili
    et al.
    KTH, School of Biotechnology (BIO), Theoretical Chemistry and Biology.
    Jiang, Jun
    Luo, Yi
    KTH, School of Biotechnology (BIO), Theoretical Chemistry and Biology.
    Elastic and inelastic electron transport in metal-molecule(s)-metal junctions2013In: Physica. E, Low-Dimensional systems and nanostructures, ISSN 1386-9477, E-ISSN 1873-1759, Vol. 47, p. 167-187Article, review/survey (Refereed)
    Abstract [en]

    An overview of studies on-elastic and inelastic electron transport properties of molecular junction devices is presented. The development of the experimental fabrication and characterization of molecular junctions as well as the corresponding theoretical modeling is briefly summarized. The functions of molecular devices are generally governed by the intrinsic structure-property relationships, and strongly affected by various environment factors including temperature, solvent and intermolecular interactions. Those detailed structural and environmental information could be probed by a powerful tool of inelastic electron tunneling spectroscopy, for which the theoretical modeling becomes particularly important. With many successful examples, it is demonstrated that the combination of theoretical simulations and experimental measurements can help not only to understand the electron-phonon interaction, but more importantly also to accurately determine the real configurations of molecules inside the junctions.

  • 30.
    Lindberg, Hanna
    KTH, School of Biotechnology (BIO), Protein Technology.
    Engineering of Affibody molecules targeting the Alzheimer’s-related amyloid β peptide2015Doctoral thesis, comprehensive summary (Other academic)
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    Thesis
  • 31. Lorenz, Dagmar
    et al.
    Åsberg, Cecilia
    KTH, School of Architecture and the Built Environment (ABE), Philosophy and History, History of Science, Technology and Environment.
    Fredengren, Christina
    Sõrmus, Maris
    Treusch, Pat
    Vehviläinen, Marja
    Zekany, Eva
    Žeková, Lucie
    Anthropocene Ecologies: Biogeotechnical Relationalities in Late Capitalism2016In: New Materialism Cost ActionArticle in journal (Refereed)
    Abstract [en]

    This position paper outlines a multidirectional approach to what we call Anthropocene ecologies, its diverse genealogies, and methodological and conceptual foci. Under the heading of Anthropocene ecologies we seek to fertilize the sciences of ecology with approaches of queer and feminist new materialisms, and engage in multiple collaborations across the humanities, sciences, and everyday ecological practices. Specifically we draw on ecology as the object of analysis and the methodology, building on concepts and approaches from the sciences, material feminisms, science and technology studies, human/animal studies and material ecocriticism. Five modes of attention become particularly salient for our analysis of the Anthropocene ecologies of solar energy, humananimal relations, organic food production, wetlands, and human-robot relations. First we attend to how these ecologies are generated within and affect the webs of multispecies ecologies in late capitalism. Second we suggest the concept of biogeotechno-power to capture the entanglements of the biological, the geologic and the technological in new formations of power that invest, regulate, enhance, and dispose of (more-than-)human bodies in particular ecological relationalities. Third we examine the multiplicities of ecological temporalities, including the deep time of mineralisation, fossilisation and past and future species survival. Fourth we attend to affect as an entangling force in ecological relations. And fifth we investigate an affirmative posthuman ethics of concern and response-ability in relations with living and nonliving materialities that might not be close by (spatially and/or temporally). Anthropocene ecologies thereby include the technical, informational, temporal, affective, and ethical as integral parts of ecological intra-actions, and remain attuned to the differential, paradoxical and unexpected.

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    Anthropocene Ecologies
  • 32.
    Maler, David
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Creating Energy Awareness at Coca-Cola Enterprises Sweden2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
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    Maler David EGI-2013-008 MSc
  • 33.
    Molin, Elvira
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. IVL Svenska Miljöinstitutet.
    Toward a more sustainable food system using public procurement2023Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Around 30 % of today's anthropogenic greenhouse gas emissions originate from the food sector. Food production is the lead cause of deforestation, biodiversity loss, depletion of fish stocks, and scarcity of fresh water. The planetary resources rapidly decrease with a continually growing population demanding resourceintense food, such as dairy and animal protein. The global production of calories satisfies human needs, but while some suffer from hunger, even more, suffer from overweight or obesity.

    For a food system to be sustainable, it must not negatively impact the three pillars of sustainability, i.e., economic, environmental, and social. One of the main challenges for the food system is to reduce the environmental impact to operate and stay within the planetary boundaries.

    Three million public meals are served daily in Sweden. Public procurement has been recognized as a powerful tool with potential to promote quality and educate change. Previous research has shown that implementing sustainability criteria in the procurement document leads to an increase in certified products in procurements. The National Agency for Public Procurement (NAPP) in Sweden provides a library with sustainability criteria on different levels and for almost all commonly bought products. Active work with sustainability and applying sustainability criteria in procurement can contribute to pupils education health and a further sustainable food system.

    In this thesis, I frame sustainable procurement through a systematic review of academic literature and interviews with Swedish practitioners who buy or sell food products through public procurements. Furthermore, I elaborate on the Swedish actors' experienced ability to influence the procurements, the use of sustainability criteria, and barriers and opportunities toward a further sustainable food system using public procurement. The goal is to examine possible ways toward a more sustainable food system through public procurement.

    The results show that both the reviewed literature and the Swedish actors have a comprehensive take on sustainability and work with all three dimensions. Above all, the favoured sustainability aspects are predominantly procuring organically labelled and locally sourced foods. Working with food waste is recognised as important, but few initiatives are taken within the procurement process to reduce food waste. Despite a large amount of academic literature on efficiently reducing environmental impacts from the food system (mainly by dietary changes and waste reduction). The results show little interest among actors in promoting these specific public sector actions. The Swedish actors are overall satisfied with the services and the criteria library provided by the NAPP. A majority of the respondents contributed to writing and reviewing the criteria, adding to the criteria’s acceptance and usage within the sector.

    There are several initiatives already taken by policymakers, procuring authorities, and not the least, the market to improve sustainability in the food system. iv Stockholm, Sverige 2023 Nevertheless, actions must be taken at multiple levels simultaneously to address the scale of our sustainability challenges. This thesis contributes knowledge that can guide future research toward sustainable food systems, bridge the stakeholder’s priorities with research where they differ today, and fully use the potential in public procurements.

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  • 34.
    Molin, Elvira
    et al.
    KTH, School of Architecture and the Built Environment (ABE).
    Lingegård, Sofia
    KTH, School of Architecture and the Built Environment (ABE).
    Martin, Michael
    KTH, School of Architecture and the Built Environment (ABE).
    Björklund, Anna
    KTH, School of Architecture and the Built Environment (ABE).
    Sustainable public food procurement: actors’ role and influenceManuscript (preprint) (Other academic)
    Abstract [en]

    This study examines the interpretation and incorporation of sustainability in public foodprocurement by interviewing stakeholders, such as procurement officers, wholesalers, chefs,and food producers. Findings highlight a consensus on the need for sustainability measures,such as purchasing local and organic products, but disagreements on the most influentialactors in the process. The influence of system-level factors, including market dynamics andregulatory frameworks, plays a significant role in implementing sustainable procurement.There is trust in the organic label and locally sourced products, yet actors require furtherpractical examples and hands-on solutions to facilitate their work towards a more sustainablefood system for the future. 

  • 35.
    Mouayn, Zouhair
    et al.
    KTH, School of Engineering Sciences (SCI), Mathematics (Dept.). Sultan Moulay Slimane Univ, Fac Sci & Tech MGhila, Dept Math, Beni Mellal, Morocco.
    Yamani, Hashim A.
    Dar AL Jewar Knowledge Econ City, Medina, Saudi Arabia..
    Coherent states of systems with pure continuous energy spectra2021In: Journal of Mathematical Physics, ISSN 0022-2488, E-ISSN 1089-7658, Vol. 62, no 6, article id 063510Article in journal (Refereed)
    Abstract [en]

    While dealing with a Hamiltonian with a continuous spectrum, we use a tridiagonal method involving orthogonal polynomials to construct a set of coherent states obeying a Glauber-type condition. We perform a Bayesian decomposition of the weight function of the orthogonality measure to show that the obtained coherent states can be recast in the Gazeau-Klauder approach. The Hamiltonian of the l-wave free particle is treated as an example to illustrate the method. Published under an exclusive license by AIP Publishing.

  • 36.
    Nathaniel, Hanna
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Franzén, Daniel
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Gröndahl, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Regional variations in the chemical composition of fresh and composted beachcast on the island of Gotland, Sweden – considering future treatmentsManuscript (preprint) (Other academic)
    Abstract [en]

    Harvesting beachcast from coastal zones to use the biomass in agriculture or horticulture could mitigate eutrophication while contributing to resource substitution of fossil-based inputs in food production. As such, beachcast holds great resource potential in a bio-based circular economy, but its chemical properties prove challenging, and more research is required to develop treatment techniques that will allow the realisation of such a system. We compiled results from chemical analyses of fresh beachcast from a database within the marine policy scheme, LOVA, in Gotland, Sweden, to study local and seasonal variations in macronutrients, C:N ratio, and Cd content. This data complemented with analyses of fresh and composted beachcast (passive pile treatment), for which the contents of macronutrient, ammonium, nitrate, and Cd, were measured, calculating C:N ratios and maturity indices (NH4+-N/NO3—N). The results confirm that regional variations in the above-mentioned properties require investments in treatment techniques and strategies to make beachcast usable. 

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  • 37.
    Nilsson, Måns
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms). Stockholm Environment Institute, Sweden.
    Griggs, Dave
    Visbeck, Martin
    Map the interactions between Sustainable Development Goals2016In: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 534, no 7607, p. 320-322Article in journal (Refereed)
  • 38.
    Nordstrand, Johan
    et al.
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Dutta, Joydeep
    KTH, School of Engineering Sciences (SCI), Applied Physics. Center of Nanotechnology King Abdulaziz University, Jeddah, 21589 Saudi Arabia.
    A new automated model brings stability to finite‐element simulations of capacitive deionization2022In: Nano Select, ISSN 2688-4011, Vol. 3, no 6, p. 1021-1035Article in journal (Refereed)
    Abstract [en]

    The massive need for freshwater is driving new desalination technologies such as capacitive deionization (CDI), wherein an applied electric field between porous electrodes removes salt ions from water. In this work, we present substantial advances in numerical approaches to 2D finite-element models that make it possible to tractably and accurately simulate the local transport, charge-transfer, and ion-adsorption processes. This is achieved by introducing a new numerical approach that improves the stability of the method (SmD), which further allows precise and effective modeling that was previously too unstable for use in the state-of-the-art 2D models. The results show that the model now accurately and reliably simulates CDI processes while being effectively applicable to a wider range of structural (device level) and operational conditions (like flow). Crucially, this opens up new opportunities that allow us to provide novel insights into the CDI processes, especially relating to ion-starved conditions. Finally, novel algorithms support fully automatic implementation with simultaneous fit to multiple data sets and we openly provide all software code to increase accessibility. Thus, we fundamentally believe that the developed model will provide a solid foundation for 2D spatiotemporal simulations of capacitive deionization and aid the future development of CDI technology.

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  • 39.
    Nordstrand, Johan
    et al.
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Dutta, Joydeep
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Fully 3D modeling of electrochemical deionizationManuscript (preprint) (Other academic)
    Abstract [en]

    Electrochemical deionization devices are crucial for meeting the global fresh water demands. One such is capacitive deionization (CDI), which is an emerging technology especially for brackish water desalination wherein supercapacitor devices extract salt ions from water. Here, we extend an electrolytic-capacitor (ELC)model that exploits the similarities between CDI systems and supercapacitor/battery systems. Thanks to the stability and flexibility the approach brings, the current work can present the first fully coupled and spatiotemporal 3D CDI model. This can be beneficial for investigating asymmetric CDI device structures, and the work focuses on a new generation flow-through device structure with inlet and outlet pipes at the center and corners, respectively. The results show that dead (low-flow) areas can reduce desalination rates while also raising the total leakage. However, the ionic flux in this device is still enough under normal operating conditions to ensure reasonable performance. In conclusion, researchers will now have some flexibility in designing device structures that are not perfectly symmetric (real-life case), and hence we share the model files to facilitate future research with 3D modeling of these electrochemical deionization devices.

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  • 40.
    Nordstrand, Johan
    et al.
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Dutta, Joydeep
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Ohmic charging in capacitive deionization: efficient water desalination using capacitive spacersManuscript (preprint) (Other academic)
    Abstract [en]

    Capacitive deionization (CDI) is a promising desalination technology based on electrosorption on the surfaces ofnanoporous electrodes. However, low total dissolved solids (TDS) in the water restricts its efficacy. In this work, we develop the theory of capacitive spacers in CDI. The investigations reveal a mechanism that we call ohmic charging; that is, the resistive losses in the spacer region drive adsorption in the capacitive spacer. As a consequence, the obtained results show that such spacers can improve desalination energy efficiency, especially at ion-starved conditions. The spacers also enhance the charging rate of the electrodes because the overall resistance is lower when the current can pass the spacer material instead of the solution, through the adsorption of anions on one side and cations on the other. Going deeper, the investigations reveal a major challenge; the spacer naturally discharges on the same timescale as the electrode charging timescale. However, only the fast timescale matters with low ionic content solutions, and under these conditions the capacitive spacers are found to be superior. Put together, capacitive spacers can make a significant difference, especially when the ion concentration is low or the cycle times are short. 

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  • 41.
    Nordstrand, Johan
    et al.
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics. Functional Materials, Applied PhysicAlbaNova universitetscentrum, SE-106 91 Stockholm, Sweden.
    Kloo, Lars
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Electrostatic interactions and physisorption: mechanisms of passive cesium adsorption on Prussian blue2022In: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 24, no 41, p. 25452-25461Article in journal (Refereed)
    Abstract [en]

    The dangers posed by nuclear accidents necessitate developments in techniques for cesium removal. One such is the adsorption of cesium cations in Prussian blue (PB) materials, on which adsorption can be a substation process or pure physisorption. The underlying mechanism of the latter is not well understood, although a Langmuir isotherm is frequently used to model experimental results. In this work, we exploit tight-binding density-functional theory (DFTB) methods to probe the atomic interactions in the physisorption process. The results show that there is a diminishing return for the energy of adsorption as more sites are filled. This means that the adsorption sites are not independent, as stipulated by the ideal Langmuir isotherm. Instead, the results indicate that electrostatic effects need to be considered to explain the theoretical and experimental results. Therefore, an electrostatic Langmuir (EL) model is introduced, which contains an electrostatic ideality correction to the classic Langmuir isotherm. For future materials development, these physical insights indicate that shielding effects as well as the number of independent physical sites must be considered when synthesizing effective Prussian blue analogs (PBA). In conclusion, the study provides insights into the limiting mechanisms in the physisorption of cesium cations on PB.

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  • 42.
    Nordstrand, Johan
    et al.
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Toledo Carrillo, Esteban
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Dutta, Joydeep
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Tuning the cation/anion adsorption balance with a multi-electrode capacitive-deionization processManuscript (preprint) (Other academic)
  • 43.
    Olsson, Alexander
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Campana, Pietro Elia
    Lind, Mårten
    Yan, Jinyue
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Energy Processes. Mälardalen University, Sweden .
    Potential for carbon sequestration and mitigation of climate change by irrigation of grasslands2014In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 136, p. 1145-1154Article in journal (Refereed)
    Abstract [en]

    The climate change mitigation potential of irrigation powered by a photovoltaic water pumping system (PVWPS) to restore degraded grasslands has been investigated using the Intergovernmental Panel on Climate Change (IPCC) 2006 Guidelines for National Greenhouse Gas Inventories for Agriculture, Forestry and Other Land Use. The purpose of this study is to develop a generic and simple method to estimate the climate change mitigation benefit of a PVWPS. The possibility to develop carbon credits for the carbon offset markets has also been studied comparing carbon sequestration in grasslands to other carbon sequestration projects. The soil carbon sequestration following irrigation of the grassland is calculated as an annual increase in the soil organic carbon pool. The PVWPS can also generate an excess of electricity when irrigation is not needed and the emissions reductions due to substitution of grid electricity give additional climate change mitigation potential. The results from this study show that the carbon sequestration and emissions reductions benefits per land area using a PVWPS for irrigating grasslands are comparable to other carbon sequestration options such as switching to no-till practice. Soil carbon in irrigated grasslands is increased with over 60% relative to severely degraded grasslands and if nitrogen fixing species are introduced the increase in soil organic carbon can be almost 80%. Renewable electricity generation by the PVWPS will further increase the mitigation benefit of the system with 70-90%. When applying the methodology developed in this paper to a case in Qinghai, China, we conclude that using a PVWPS to restore degraded grasslands for increased grass production and desertification control has a climate change mitigation benefit of 148 Mg (1 Mg = 1 metric ton) CO2-equivalents (CO2-eq) per hectare in a cold temperate, dry climate during a 20 year process of soil organic carbon sequestration and emissions reductions. Leakage due to an increase in N2O emissions from the additional biomass production and introduction of nitrogen fixing species is included in this result. The most important conclusion from our case is that if soil carbon sequestration is lower than 24 Mg CO2-eq per hectare including leakage, then the climate change mitigation benefit is larger if PV is used to produce electricity for the grid.

  • 44. Ouassou, Mohammed
    et al.
    Jensen, Anna B. O.
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Geodesy and Satellite Positioning.
    Validation of New Method for Network RTK Data Screening by Multivariate Analysis2020Conference paper (Refereed)
  • 45.
    Pabon, Peter
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Speech, Music and Hearing, TMH. Institute of Sonology, Royal Conservatory.
    Mapping Individual Voice Quality over the Voice Range: The Measurement Paradigm of the Voice Range Profile2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The acoustic signal of voiced sounds has two primary attributes: fundamental frequency and sound level. It has also very many secondary attributes, or ‘voice qualities’, that can be derived from the acoustic signal, in particular from its periodicity and its spectrum. Acoustic voice analysis as a discipline is largely concerned with identifying and quantifying those qualities or parameters that are relevant for assessing the health or training status of a voice or that characterize the individual quality. The thesis presented here is that all such voice qualities covary essentially and individually with the fundamental frequency and the sound level, and that methods for assessing the voice must account for this covariation and individuality. The central interest in the "voice field" measurement paradigm becomes to map the proportional dependencies that exist between voice parameters. The five studies contribute to ways of doing this in practice, while the framework text presents the theoretical basis for the analysis model in relation to the practical principles.

    Download full text (pdf)
    Thesis_P_Pabon_2018
  • 46.
    Pabon, Peter
    Institute of Sonology, Royal Conservatory.
    Objective acoustic voice-quality parameters in the computer phonetogram1991In: Journal of Voice, ISSN 0892-1997, E-ISSN 1873-4588, Vol. 5, no 3, p. 203-216Article in journal (Refereed)
  • 47.
    Pabon, Peter
    et al.
    Institute of Sonology, Royal Conservatory, The Hague.
    Plomp, Reinier
    Free University, Amsterdam.
    Automatic phonetogram recording supplemented with acoustic voice quality parameters1989In: Journal of Speech, Language and Hearing Research, ISSN 1092-4388, E-ISSN 1558-9102, Vol. 31, p. 710-722Article in journal (Refereed)
  • 48.
    Patton, Declan
    et al.
    The University of New South Wales, Sydney, Australia.
    McIntosh, Andrew
    The University of New South Wales, Sydney, Australia.
    Kleiven, Svein
    KTH, School of Technology and Health (STH), Neuronic Engineering.
    Brain loading in concussive head impacts: implications for injury prevention2011In: British Journal of Sports Medicine, ISSN 0306-3674, E-ISSN 1473-0480, Vol. 45, no 318Article in journal (Refereed)
    Abstract [en]

    Background Concussion is a prominent injury risk in sport, but the mechanisms that cause concussion are unclear. An important debate centres on the roles of angular and linear head acceleration in the mechanism of concussion. Resolving this debate is a prerequisite for developing injury prevention methods.                                

    Objective To estimate the brain loading patterns in a case series of concussive and no-injury head impacts. To assess the relative affects of linear and angular acceleration on brain loading and injury.                                

    Design Biomechanical analysis of head impacts using the validated KTH human head finite element model to analyse brain loading patterns in reconstructed head impacts.                                

    Setting Professional male unhelmeted contact football.                                

    Participants Biomechanical data from a previous case series study of 40 male football players (concussed and no-injury).                                

    Main outcome measurements Maximum principle strain, a predictor of injury, was measured in discrete brain locations.                                

    Results The highest maximum principle strains were recorded in both the white and grey matter of the cerebrum. Strains in all brain regions were similar across all three grades of concussion (Cantu Revised Concussion Grading Guidelines), but lower (33–47%) for no-injury cases. Concussion was most correlated with strains in the brainstem and thalamus. Angular, rather than linear, resultant accelerations correlated higher to strains in all regions of the brain. Angular accelerations in the coronal plane and linear accelerations directed inferiorly had the greatest correlation to concussion and loss of consciousness. For linear accelerations, those directed laterally and inferiorly were most correlated with strain. Angular accelerations in the coronal plane correlated highly with strains in the brainstem, thalamus, and midbrain. Angular accelerations in the transverse plane correlated highly with strains in the cerebrum and corpus callosum.                                

    Conclusion Brain loading differences were observed between concussion and no-injury cases. Angular acceleration may play a more important role in the mechanism of concussion than linear acceleration.

  • 49.
    Pereverza, Kateryna
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Resources, Energy and Infrastructure.
    Kordas, Olga
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Resources, Energy and Infrastructure.
    Sustainability through stakeholder learning: Participatory backcasting for the heating sector2017In: 10th BIWAES Biennial International Workshop Advances in Energy Studies: Energy futures, environment and well-being / [ed] Sergio Ulgiati and Laura Vanoli, Budapest, 2017Conference paper (Refereed)
    Abstract [en]

    Social learning is an important element of the reflexive governance approaches needed to enable sustainability transitions. One such approach is participatory backcasting (PB), which involves development of a desirable future vision and a pathway towards this vision. Social learning has been reported as an outcome of different PB projects, including those performed in the infrastructure sector. This study examined the importance of sharing and transferring knowledge and new perceptions developed during PB projects among the individuals directly involved in these projects to and within their formal and informal groups and organisations (e.g. local authorities, DH companies, equipment producers, consumer associations). Mechanisms that need to be incorporated into PB processes to support knowledge sharing/transfer were identified as: (1) use of actor role profiles to identify individuals with bridging/connecting/change agent capability for inclusion in a PB process; (2) strong participant engagement in co-creation activities during the PB project; and (3) PB process design to achieve the multiplier effect (e.g. capacity-building workshops for local researchers and authorities). These mechanisms were successfully tested using the case of two PB-based projects seeking sustainability in the heating sector of the Ukrainian city Bila Tserkva and the Serbian city Niš. It was concluded that further investigation of mechanisms for knowledge sharing/transfer and experimentation within PB processes is a promising research area for enabling sustainability transitions in the heating sector.

  • 50.
    Persson, Erik
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Geoinformatics.
    Olika metoder för positionering och inventering av träd i stadsmiljö2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    There are several advantages with establishing a database of the trees of a city. The trees contribute great value ​​to the urban environment and are therefore important to take care of, especially because urban trees often live in a stressed habitat. In order to establish a database of the trees of a city, there are various methods to perform an inventory. The two main areas are field methods and techniques based on remote sensing. The field methods can be divided into terrestrial surveying with a total station and measurement with some kind of hand-held GNSS receiver. The remote methods that are of interest when analyzing trees can be divided into laser scanning and aerial photographic methods. The different methods are described in the report and their possibilities, advantages and disadvantages are investigated.

    The method that over a larger area may be considered to be most effective begins with a laser scanning. From the laser data each tree can be detected and information about tree height and also some information about tree species can be extracted. If more information about the trees is needed, a near-infrared orthophoto can be used. With some manual processing tree species can then be extracted with greater certainty.

    To improve possibilities and accuracy for determining wood affiliation hyper spectral images could be used. These are however not yet implemented in commercial procedures and more research is needed.

    The database obtained from the procedure described above may, decided by demand and budget, be supplemented with field surveys to obtain the desired attributes.

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