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  • 1.
    Ahmad, Arslan
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik. 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 arsenic2014Rapport (Övrigt vetenskapligt)
    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.

  • 2.
    Aid, Graham
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell ekologi.
    Brandt, Nils
    KTH, Skolan för industriell teknik och management (ITM), Industriell ekologi.
    Action Research In Waste Management: Application to construction and demolition waste in the Stockholm region2010Ingår i: Linnaeus ECO-TECH ´10 / [ed] Fabio Kaczala, Linnaeus University , 2010, s. 1009-1019Konferensbidrag (Refereegranskat)
    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.

  • 3.
    Bergsjö, Joline
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och geoinformatik.
    Object based change detection in urban area using KTH-SEG2014Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Idag flyttar fler och fler människor in i städer runt om i världen. Det utgör en stor påverkan på den befintliga infra-strukturen då städerna växer på både höjden och bredden. För att kunna bevaka den förändring som sker så används ofta fjärranalys som ett effektivt verktyg. Sätt att utveckla befintliga tekniken försöker man hela tiden hitta nya, enklare och mer effektiva sätt att bevaka förändring finns alltid på horisonten.

    Objektbaserad förändrings analys är ett sätt att bevaka förändringar. Iden om att använda objekt baserad analys har funnits sedan 70-talet, men det var först i början av 2000-talet, då Blaschke och Strobl(2001) introducerade tekniken som en lösning på de problem man stöter på i pixelbaserad analys, som tekniken blev populär bland fjärranalytiker världen över.

    KTH-SEG är ett program utvecklat på KTH Geoinformatik avdelning. KTH-SEG är utvecklat för att segmentera bilder inför objektbaserad analys. Dessutom utför programmet klassificering.

    I det här arbetet utförs objektbaserad förändrings analys över ett område i Shanghai. För att hitta de förändringar som har skett har två tillvägsgångssätt använts: dels har analys av bilder efter klassificeringen gjorts och dels har bilder som i sig själva skall visa den förändring som har skett skapats, så kallade förändringsbilder. Bildernas pålitlighet är utvärderad genom att använda ”maximum likelihood report” i programmet Geomatica.

     

    Segmentering och klassificering är gjort i programmet KTH-SEG, träningsområden och testområden är skapade i ArcGIS och förbehandling av bilder samt andra operationer är gjorda i Geomatica.

    KTH-SEG erbjuder många valmöjligheter för att påverka segmenteringsresultatet. Den är enkelt att använda och producerar tydliga klassificerade bilder som är användbara för analys.

    Resultatet utvärderas för att bestämma hur effektivt det är att använda objektbaserad förändrings analys av urbana områden och KTH-SEG utvärderas som ett segmenterings- och klassifikations verktyg.

    Resultaten visar att förändringsbilder ger ett sämre resultat än bilder som analyseras efter klassifikationen. Huruvida det dåliga resultatet på förändingsbilderna beror på andra omständigheter än tillvägagångssättet med objekt baserad klassifikation kan inte bestämmas. Mycket tyder dock på att det är valet av två bilder från olika satelliter som ger det dåliga resultatet.

  • 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-fillers2009Ingår i: Annual Report - Conference on Electrical Insulation and Dielectric Phenomena, 2009, s. -380Konferensbidrag (Refereegranskat)
    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, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Industriell ekologi.
    Ericson, Molly
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Industriell ekologi.
    Frid, Gustav
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Industriell ekologi.
    Biofuel: - Sustainability of the Jatropha cultivation in Zambia2012Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
  • 6.
    Calil Kores, Cristine
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Material- och nanofysik.
    Ismail, Nur
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Material- och nanofysik.
    Geskus, Dimitri
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Material- och nanofysik.
    Dijkstra, M.
    Bernhardi, Edward H.
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Material- och nanofysik.
    Pollnau, Markus
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Material- och nanofysik.
    Temperature dependence of the resonance line of optically pumped distributed-feedback lasers2018Ingår i: Optics InfoBase Conference Papers, OSA - The Optical Society , 2018Konferensbidrag (Refereegranskat)
    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, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH.
    Doellinger, Michael
    Burdumy, Michael
    Richter, Bernhard
    Herbst, Christian Thomas
    Laryngeal evidence for the first and second passaggio in professionally trained sopranos2017Ingår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 12, nr 5, artikel-id e0175865Artikel i tidskrift (Refereegranskat)
    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 characteristics2010Ingår i: Proceedings of the 2010 IEEE International Conference on Solid Dielectrics, ICSD 2010, 2010Konferensbidrag (Refereegranskat)
    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, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Urbana och regionala studier.
    Naturvård i den urbana miljön: En studie kring naturvård med häst i en tid av urban förtätning2018Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    När man inom stadsplanering strävar efter att förtäta städer och urbana miljöer blir balansen mellan stad och natur allt viktigare, särskilt som befolkningen växer och behovet av täta städer lika så. Också medvetenheten om funktionerna i dessa grönområden blir betydelsefulla när naturen och dess tjänster ska planeras in som resurser i samhället på en begränsad yta. För att bevara de många värden och ekosystemtjänster som naturen tillhandahåller åt samhället behöver dessa områden skötas på ett lämpligt sätt. Syftet med denna studie är att undersöka naturvård med hjälp av häst i urbana miljöer och de värden det skapar. Vidare utreds hur naturvård kan skapa förutsättningar för olika ekosystemtjänster och gröna värden. Som metod användes en litteraturstudie och en fallstudie bestående av intervjuer och en dokumentstudie med granskning av plandokument.

    Slutsatsen som drogs från studien är att naturen skapar många värden – ekologiska, sociala och ekonomiska – för samhället och att dessa behöver tas omhand för att samtliga värden ska kunna åtnjutas även framöver. Naturvård med häst är ett på många sätt effektivt sätt att sköta natur och grönområden och därigenom bevara och utveckla de värden och tjänster för vidare nyttjande. Naturvård med häst bidrar även i sig med sociala och pedagogiska värden då djuren är uppskattade av människor och det stimulerar lärande och ny kunskap. Naturvård med häst kan bli mer kostsamt än andra metoder beroende på beställd åtgärd när entreprenör anlitas men vinsterna i de olika värdena anses kunna väga upp den kostnaden. Det finns många värden att hämta från att integrera häst i naturvården helt eller delvis.  

  • 10.
    Frid, Emma
    et al.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Medieteknik och interaktionsdesign, MID.
    Bresin, Roberto
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Medieteknik och interaktionsdesign, MID.
    Sallnäs Pysander, Eva-Lotta
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Medieteknik och interaktionsdesign, 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 Feedback2017Ingår i: Proceedings of the 14th Sound and Music Computing Conference / [ed] Tapio Lokki, Jukka Pätynen, and Vesa Välimäki, Espoo, Finland, 2017, s. 242-249Konferensbidrag (Refereegranskat)
    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, Skolan för elektroteknik och datavetenskap (EECS), Medieteknik och interaktionsdesign, MID.
    Elblaus, Ludvig
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Medieteknik och interaktionsdesign, MID.
    Bresin, Roberto
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Medieteknik och interaktionsdesign, MID.
    Interactive sonification of a fluid dance movement: an exploratory study2019Ingår i: Journal on Multimodal User Interfaces, ISSN 1783-7677, E-ISSN 1783-8738, Vol. 13, nr 3, s. 181-189Artikel i tidskrift (Refereegranskat)
    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.2016Självständigt arbete på avancerad nivå (masterexamen), 40 poäng / 60 hpStudentuppsats (Examensarbete)
    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, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi.
    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 states2017Ingår i: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 147, nr 4, artikel-id 044310Artikel i tidskrift (Refereegranskat)
    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, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Cederwall, Bo
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Qi, Chong
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Ataç, Ayşe
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Liotta, Roberto
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Doncel, Maria
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Johnson, Arne
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    et al.,
    Spectroscopy of the neutron deficient N=50 nucleus 95Rh2014Manuskript (preprint) (Övrigt vetenskapligt)
  • 15.
    Giummarella, Nicola
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Balakshin, Mikhail
    Koutaniemi, Sanna
    Kärkönen, Anna
    Lawoko, Martin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Nativity of lignin carbohydrate bonds substantiated by biomimetic synthesis2019Ingår i: Journal of Experimental Botany, ISSN 0022-0957, E-ISSN 1460-2431Artikel i tidskrift (Refereegranskat)
    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.
    Hemlin, Hanna
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH).
    Lalangas, Nektaria
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH).
    Production of Biochar Through Slow Pyrolysis of Biomass: Peat,Straw, Horse Manure and Sewage Sludge2018Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    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.

  • 17.
    Jacob, Alexander
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och geoinformatik.
    Ban, Yifang
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och geoinformatik.
    Segmentation of multi-temporal envisat asar and hj-1b optical data using an edge-aware region growing and merging algorithm2013Ingår i: European Space Agency, (Special Publication) ESA SP, Volume 704 SP, 2013, 2013Konferensbidrag (Refereegranskat)
    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.

  • 18.
    Johansson, Mats
    et al.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Ytbehandlingsteknik.
    Hedlund, Hans Peter
    Prototypes of Lascaux´s medium for consolidation2005Ingår i: Restauro: Zeitschrift für Kunsttechniken, ISSN 0933-4017, Vol. 6, s. 432-439Artikel i tidskrift (Refereegranskat)
  • 19.
    Kolmskog, Peter
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Metallografi.
    Borgenstam, Annika
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Metallografi.
    Hillert, Mats
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Hedström, Peter
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Metallografi.
    Babu, Sudarsanam Suresh
    Terasaki, Hidenori
    Komizo, Yu-Ichi
    Direct Observation that Bainite can Grow Below M-S2012Ingår i: Metallurgical and Materials Transactions. A, ISSN 1073-5623, E-ISSN 1543-1940, Vol. 43A, nr 13, s. 4984-4988Artikel i tidskrift (Refereegranskat)
    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.

  • 20.
    Kroon, Martin
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Hållfasthetslära (Inst.).
    Holzapfel, Gerhard A.
    KTH, Skolan för teknikvetenskap (SCI), Hållfasthetslära (Inst.).
    A theoretical model for saccular cerebral aneurysm growth: Deformation and stress-analysis2007Ingår i: Proceedings of the ASME Summer Bioengineering Conference 2007, 2007, s. 255-256Konferensbidrag (Refereegranskat)
  • 21.
    Li, Hong-bao
    et al.
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi.
    Lin, Zi-jing
    Luo, Yi
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi.
    Local Structures and Chemical Properties of Deprotonated Arginine2012Ingår i: Chinese Journal of Chemical Physics, ISSN 1674-0068, Vol. 25, nr 6, s. 681-686Artikel i tidskrift (Refereegranskat)
    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.

  • 22.
    Liljenström, Carolina
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Hållbarhet, utvärdering och styrning.
    Life cycle assessment in early planning of transport systems: Decision support at project and network levels2018Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    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. 

  • 23.
    Liljenström, Carolina
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Hållbarhet, utvärdering och styrning.
    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, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Hållbarhet, utvärdering och styrning.
    Life cycle assessment as decision-support in choice of road corridor: case study and stakeholder perspectivesManuskript (preprint) (Övrigt vetenskapligt)
    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.

  • 24.
    Liljenström, Carolina
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Hållbarhet, utvärdering och styrning.
    Toller, Susanna
    The Swedish Transport Administration.
    Åkerman, Jonas
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Strategiska hållbarhetsstudier.
    Björklund, Anna
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Hållbarhet, utvärdering och styrning. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö.
    Annual climate impact and primary energy use of Swedish transport infrastructureManuskript (preprint) (Övrigt vetenskapligt)
    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.

  • 25.
    Liljenström, Carolina
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Hållbarhet, utvärdering och styrning.
    Åkerman, Jonas
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Strategiska hållbarhetsstudier.
    Björklund, Anna
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Hållbarhet, utvärdering och styrning. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö.
    Toller, Susanna
    The Swedish Transport Administration.
    Direct and indirect climate impact and primary energy use of the Swedish transport systemManuskript (preprint) (Övrigt vetenskapligt)
  • 26.
    Lin, Lili
    et al.
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi.
    Jiang, Jun
    Luo, Yi
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi.
    Elastic and inelastic electron transport in metal-molecule(s)-metal junctions2013Ingår i: Physica. E, Low-Dimensional systems and nanostructures, ISSN 1386-9477, E-ISSN 1873-1759, Vol. 47, s. 167-187Artikel, forskningsöversikt (Refereegranskat)
    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.

  • 27.
    Lindberg, Hanna
    KTH, Skolan för bioteknologi (BIO), Proteinteknologi.
    Engineering of Affibody molecules targeting the Alzheimer’s-related amyloid β peptide2015Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
  • 28. Lorenz, Dagmar
    et al.
    Åsberg, Cecilia
    Filosofi och historia, KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Filosofi och teknikhistoria, Historiska studier av teknik, vetenskap och miljö.
    Fredengren, Christina
    Sõrmus, Maris
    Treusch, Pat
    Vehviläinen, Marja
    Zekany, Eva
    Žeková, Lucie
    Anthropocene Ecologies: Biogeotechnical Relationalities in Late Capitalism2016Ingår i: New Materialism Cost ActionArtikel i tidskrift (Refereegranskat)
    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.

  • 29.
    Maler, David
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Tillämpad termodynamik och kylteknik.
    Creating Energy Awareness at Coca-Cola Enterprises Sweden2013Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
  • 30.
    Nilsson, Måns
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Miljöstrategisk analys (fms). Stockholm Environment Institute, Sweden.
    Griggs, Dave
    Visbeck, Martin
    Map the interactions between Sustainable Development Goals2016Ingår i: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 534, nr 7607, s. 320-322Artikel i tidskrift (Refereegranskat)
  • 31.
    Olsson, Alexander
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik.
    Campana, Pietro Elia
    Lind, Mårten
    Yan, Jinyue
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Energiprocesser. Mälardalen University, Sweden .
    Potential for carbon sequestration and mitigation of climate change by irrigation of grasslands2014Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 136, s. 1145-1154Artikel i tidskrift (Refereegranskat)
    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.

  • 32.
    Pabon, Peter
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Tal, musik och hörsel, TMH. Institute of Sonology, Royal Conservatory.
    Mapping Individual Voice Quality over the Voice Range: The Measurement Paradigm of the Voice Range Profile2018Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    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.

  • 33.
    Pabon, Peter
    Institute of Sonology, Royal Conservatory.
    Objective acoustic voice-quality parameters in the computer phonetogram1991Ingår i: Journal of Voice, ISSN 0892-1997, E-ISSN 1873-4588, Vol. 5, nr 3, s. 203-216Artikel i tidskrift (Refereegranskat)
  • 34.
    Pabon, Peter
    et al.
    Institute of Sonology, Royal Conservatory, The Hague.
    Plomp, Reinier
    Free University, Amsterdam.
    Automatic phonetogram recording supplemented with acoustic voice quality parameters1989Ingår i: Journal of Speech, Language and Hearing Research, ISSN 1092-4388, E-ISSN 1558-9102, Vol. 31, s. 710-722Artikel i tidskrift (Refereegranskat)
  • 35.
    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, Skolan för teknik och hälsa (STH), Neuronik.
    Brain loading in concussive head impacts: implications for injury prevention2011Ingår i: British Journal of Sports Medicine, ISSN 0306-3674, E-ISSN 1473-0480, Vol. 45, nr 318Artikel i tidskrift (Refereegranskat)
    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.

  • 36.
    Pereverza, Kateryna
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Resurser, energi och infrastruktur.
    Kordas, Olga
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Resurser, energi och infrastruktur.
    Sustainability through stakeholder learning: Participatory backcasting for the heating sector2017Ingår i: 10th BIWAES Biennial International Workshop Advances in Energy Studies: Energy futures, environment and well-being / [ed] Sergio Ulgiati and Laura Vanoli, Budapest, 2017Konferensbidrag (Refereegranskat)
    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.

  • 37.
    Persson, Erik
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik och Geodesi.
    Olika metoder för positionering och inventering av träd i stadsmiljö2011Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Det finns flera fördelar med att upprätta en databas över en stads träd. Träden tillför många värden till stadsmiljön och är därför viktiga att sköta om, särskilt eftersom stadsträd ofta lever i en utsatt miljö. För att upprätta en träddatabas för en stad finns det olika metoder för att genomföra inventeringen. De två huvudområdena är dels fältmetoder och dels metoder som bygger på fjärranalys. Fältmetoderna kan delas in i terrester inmätning med totalstation och i mätning med någon typ av handhållen GNSS-utrustning. Fjärrmetoderna som är intressanta i trädanalysavseende kan delas in i laserskanning och flyg- eller satellitbildmetoder. De olika tillvägagångssätten beskrivs i arbetet och deras respektive möjligheter, för- och nackdelar utreds.

    Det tillvägagångssätt som över ett större område får anses vara effektivast börjar med att en laserskanning utförs. På så sätt kan varje enskilt träd detekteras och information om trädens höjd och till viss del även träslagstillhörigheten kan tas fram. Om mer information om respektive träd önskas kan ett nära-infrarött ortofoto användas. Med viss manuell bearbetning kan då träslagstillhörighet extraheras med större säkerhet.

    För att förbättra möjligheterna och noggrannheten till träslagsbestämning skulle så kallade hyperspektrala bilder kunna användas. Dessa är dock ännu ej implementerade i kommersiella metoder och mer forskning behövs.

    Den databasen som fås från ovan nämnda procedur får efter behov och möjlighet kompletteras med fältinventeringar för att inhämta önskade attributdata.

  • 38.
    Pipkorn, Bengt
    et al.
    Chalmers tekniska högskola School of Mechanical Engineering. Institutionen för tillämpad mekanik. .
    Halldin, Peter
    KTH, Skolan för teknik och hälsa (STH), Neuronik.
    Jakobsson, Lotta
    Chalmers tekniska högskola School of Mechanical Engineering. Institutionen för tillämpad mekanik. .
    Iraeus, Johan
    Backlund, ria
    Mroz, Krystoffer
    Holmqvist, Kristian
    Chalmers tekniska högskola School of Mechanical Engineering. Institutionen för tillämpad mekanik. .
    Kleiven, Svein
    KTH, Skolan för teknik och hälsa (STH), Neuronik.
    Mathematical Occupant Models in Side Impacts: A Validation Study with Particular Emphasis on the Torso and Shoulder and their Influence on Head and Neck Motion2008Ingår i: International IRCOBI Conference on the Biomechanics of Impact, 2008, s. 99-111Konferensbidrag (Refereegranskat)
    Abstract [en]

    The ability of three mathematical human body models to predict previously published human responses in two different side impact loading configurations was evaluated using an objective rating method. In particular the kinematics of the shoulder, T1 and head were evaluated. The human body models evaluated were THUMS, HUMOS 2 and the GM model. The impact loading configurations used were pendulum impact tests and sled tests. In the pendulum configurations, the closest correlation to the published responses was shown by THUMS followed by the GM model. In the sled configuration, closest correlation to the published responses was shown by HUMOS 2 followed by THUMS. According to the objective rating method the published responses in the pendulum configuration were predicted by all human body models. The published responses in the sled configuration were predicted by HUMOS 2 and THUMS.

  • 39.
    Polak, Rainer
    et al.
    Max Planck Institute for Empirical Aesthetics, Frankfurt, Germany.
    Jacoby, Nori
    Columbia University.
    Fischinger, Timo
    Max Planck Institute for Empirical Aesthetics, Frankfurt, Germany.
    Goldberg, Daniel
    University of Connecticut.
    Holzapfel, Andre
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Medieteknik och interaktionsdesign, MID.
    London, Justin
    Rhythmic Prototypes Across Cultures: A Comparative Study of Tapping Synchronization2018Ingår i: Music perception, ISSN 0730-7829, E-ISSN 1533-8312, Vol. 36, nr 1, s. 1-23Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    IT HAS LONG BEEN ASSUMED THAT RHYTHM cognition builds on perceptual categories tied to prototypes defined by small-integer ratios, such as 1:1 and 2:1. This study aims to evaluate the relative contributions of both generic constraints and selected cultural particularities in shaping rhythmic prototypes. We experimentally tested musicians' synchronization (finger tapping) with simple periodic rhythms at two different tempi with participants in Mali, Bulgaria, and Germany. We found support both for the classic assumption that 1:1 and 2:1 prototypes are widespread across cultures and for culture-dependent prototypes characterized by more complex ratios such as 3:2 and 4:3. Our findings suggest that music-cultural environments specify links between music performance patterns and perceptual prototypes.

  • 40.
    Rasmusson, Niclas
    KTH, Skolan för industriell teknik och management (ITM), Lärande.
    Motivation och lärande inaturvetenskaplig undervisning2018Självständigt arbete på avancerad nivå (yrkesexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    I denna studie undersöks hur stor vikt lärare lägger på att skapa och genomföra lektioner

    där motivation påverkar lektionens planering och genomförande. Information samlades in

    via en enkät med 119 respondentsvar från lärare. Examensarbetet består av två delar, en

    kvantitativ och en kvalitativ del. I den kvantitativa delen uppger respondenterna att

    elevmotivation är viktigt, vilket korrelerar med Hattie (2014) metaanalys. Respondentsvaren

    visar även att de i mindre utsträckning tar hänsyn till elevmotivation vid

    lektionsplaneringen.

    I den kvalitativa delen bearbetas enkätsvaren kring frågeställningen - hur informanterna

    uppger att de arbetar med att skapa förutsättningar för elevmotivation vid

    lektionsgenomförande. Respondentsvaren beskriver pragmatiskt arbetet med att skapa

    förutsättningar för elevmotivation. Analysen visar en spridning i respondentsvaren.

    Diskussion, variation och praktiska moment är några av de mest förekommande svaren.

    I det följande steget görs en ytterligare analys av respondentsvaren med hjälp av en

    analysmodell baserad på Skaalvik och Skaalvik (2016), och deras uppdelning med teorier

    kring elevmotivation i skolmiljö. Examensarbetets resultat visar att svaren härrör sig från i

    huvudsak fyra av dessa åtta teorier kring elevmotivation.

  • 41.
    Reda Adinew, Amezene
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och geoinformatik.
    Bedada Damtie, Bekele
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och geoinformatik.
    Accuracy analysis and Calibration of Total Station based on the Reflectorless Distance Measurement2012Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Sammandrag

    Reflektorlös EDM-tekniken använder fas mätning eller pulsade lasrar för att mäta mål en reflekterande och icke-reflekterande karaktär. Reflektorlös avståndsmätning ger snabb mätning genom att spara tid och arbete för inspektörer. Emellertid är noggrannheten hos dessa typer av mätningar under fråga på grund av olika begränsningar som påverkar mätningen.

    Denna uppsats försöker visa de metoder för totalstation kalibrering och att undersöka eventuella felkällor i reflektorlös avståndsmätning. Som ett resultat var effekterna av olika färger mål och vinkel inverkan på avståndsmätning kontrolleras. Noggrannheten i reflektorlös avståndsmätning undersökt också. Dessutom gjordes jämförelse för manuell och automatisk måligenkännande mätning. Ytterligare experiment utfördes på hur man kalibrerar totalstationen instrumentet och prestanda instrumentet kontrollerades av KTH-TSC programvara.

    Experimenten utvärderades genom att reflektorn läsning som "sanna värdet" för att kontrollera riktigheten i reflektorlös mätning. Effekterna av färgytor på avståndsmätning har ingen signifikant skillnad. Dessutom visar resultatet felet i avståndet ökade infallsvinkeln i målet ökar. Resultatet visar också automatiskt måligenkännande läget är det mest lämpligt tekniken för exakt mätning. Slutligen ett optimalt antal av sju målpunkter hittades för beräkning av prismakonstanten.

  • 42.
    Rollenhagen, Carl
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Filosofi och teknikhistoria, Filosofi.
    Safety Culture and Safety Quality2013Ingår i: Social and Ethical Aspects of Radiation Risk Management, Volume 19 (Radioactivity in the Environment), Elsevier, 2013, s. 215-237Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    Although much used, the concept of safety culture is associated with many meanings. In this chapter, it is argued that there are reasons to define safety culture in terms of values and competence related to safety, and to differentiate safety culture from what is here called "safety quality". It is argued that safety culture should be perceived as a relative construct in terms of how the value of safety relates to the manifold of other values simultaneously strived for. Safety culture is discussed in the context of value research (individual and organizational values) and safety quality is discussed in the context of human reliability analysis. Implications for safety management and assessment of safety culture and safety quality are discussed.

  • 43.
    Rose, Linda M
    KTH, Skolan för teknik och hälsa (STH), Hälso- och systemvetenskap, Ergonomi.
    RAMP: Ett nytt riskhanteringsverktyg   – Risk Assessment and Management tool for manual handling Proactively –: Slutrapport i projektet ”Utveckling, implementering och spridning av belastningsergonomiskt bedömningsverktyg och åtgärdsprocess” (Dnr 090168)2014Rapport (Övrigt vetenskapligt)
    Abstract [sv]

    I denna rapport beskrivs riskhanteringsmetoden RAMP – Risk Assessment and Management tool for manual handling Proactively – och dess utveckling som gjorts i projektet ”Utveckling, implementering och spridning av belastningsergonomiskt bedömningsverktyg och åtgärds-process”. Projektets mål har varit att utveckla en fritt tillgänglig metod för riskhantering för arbete med manuell hantering. Metoden ska kunna användas för att bedöma risken att utveckla belastningsbesvär och stötta det systematiska arbetsmiljöarbetet genom att ge en struktur för förbättringsåtgärder och utarbetande av handlingsplaner. Syftet är att användningen av verktyget ska bidra att arbetsmiljöförbättrande åtgärder genomförs, vilket förväntas leda till positiva hälsoeffekter.

    Projektet har genomförts som ett samarbetsprojekt med interaktiv metodologisk ansats mellan forskare vid KTH Skolan för Teknik och hälsa, Enheten för Ergonomi, och personer som aktivt deltagit i projektet i egenskap av professionella yrkesverksamma med olika roller på de medverkande företagen Arla Foods, Scania CV AB, Svenskt Butikskött AB och Mikael Loods Åkeri AB – exempelvis operatör, logistiker, chef, VD, skyddsombud, produktionstekniker, ergonom, och global arbetsmiljösmordnare. Till projektet har en referensgrupp och en expertgrupp varit knutna. Projektet har finansierats av i huvudsak Afa Försäkring och de medverkande företagen.

    Bland metoderna om används i projektet finns litteraturgenomgång, iterativ prototyp-utveckling, användartester och utvärdering av prototyper, work-shops, intervjuer och enkäter. RAMP baseras på vetenskapliga studier, svensk arbetsmiljölagstiftning, ergonomistandarder, andra bedömningsmetoder, expertbedömningar av projektets expertgrupp, erfarenheter och expertbedömningar från personer verksamma i industrin inom bland annat företagshälsovård, ledning och produktion, användartester samt referensgruppens feed-back.

    I rapporten presenteras RAMP-verktyget som består av fyra moduler: RAMP I - en checklista för screening av belastningsergonomiska riskfaktorer; RAMP II – som möjliggör en fördjupad analys; en Resultatmodul där resultatet kan presenteras på olika detaljnivå och med olika omfattning och en Åtgärdsmodul som ger stöd för det systematiska arbetsmiljöarbetet med bland annat åtgärdsförslag och en mall för att utforma handlingsplaner för att minska riskerna.

    En prototyp av RAMP har utvärderades i ett examensarbete genom validitets- och reliabilitets- och användbarhetsstudier. Utvärderingen visar på hög repeterbarhet av bedömningar genomförda av icke-experter samt att överensstämmelsen var hög mellan experter och icke-experter. Användbarhetsstudien visade att RAMP uppleveds som ganska lätt att använda och tidseffektiv.

    Digitaliseringen av RAMP förväntas bli klar under hösten 2014. RAMP kommer därefter att göras fritt tillgänglig via KTH STHs hemsida och en implementeringsstudie av metoden sker på de medverkande företagen. Metoden kommer att spridas enligt projektets kommunikationsplan som beskrivs i rapporten.

  • 44. Rossing, T D
    et al.
    Sundberg, Johan
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Tal, musik och hörsel, TMH, Musikakustik.
    Ternström, Sten
    Acoustic comparison of voice use in solo and choir singing.1986Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 79, nr 6, s. 1975-1981Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    An experiment was carried out in which eight bass/baritone singers were recorded while singing in both choral and solo modes. Together with their own voice, they heard the sound of the rest of the choir and a piano accompaniment, respectively. The recordings were analyzed in several ways, including computation of long-time-average spectra for each passage, analysis of the sound levels in the frequency ranges corresponding to the fundamental and the "singer's formant," and a comparison of the sung levels with the levels heard by the singers. Matching pairs of vowels in the two modes were inverse filtered to determine the voice source spectra and formant frequencies for comparison. Differences in both phonation and articulation between the two modes were observed. Subjects generally sang with more power in the singer's formant region in the solo mode and with more power in the fundamental region in the choral mode. Most singers used a reduced frequency distance between the third and fifth formants for increasing the power in the singer's formant range, while the difference in the fundamental was mostly a voice source effect. In a choral singing mode, subjects usually adjusted their voice levels to the levels they heard from the other singers, whereas in a solo singing mode the level sung depended much less on the level of an accompaniment.

  • 45.
    Rostami, Jowan
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH).
    Zwitterionic Acetylated Cellulose Nanofibres for Design of Smart Water Filter Systems2018Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Det finns en ökande efterfrågan inom dagens samhälle att utveckla mer effektiva och hållbara vattenfiltermembran från biobaserade källor för rening av kontaminerat vatten. Tack vare Sveriges enorma tillgång till skog är trä ett väldigt fördelaktigt material att utgå ifrån för utveckling av framtida material. Flertalet komponenter kan utvinnas från trä, däribland cellulosa som redan är väldigt kommersiellt etablerat och välanvänt i samhället. Cellulosananofibrer (CNF) används flitigt i forskning idag tack vare dess stora ytarea och fördelaktiga mekaniska samt kemiska egenskaper. Dock måste CNF ofta modifieras för användning i mer avancerade applikationer. Syftet med denna studie var att utforska diverse funktionaliseringar av CNF för att uppnå förbättrade materialegenskaper för användning i vattenfiltersystem. I den här studien erhölls zwitterjonisk acetylerad CNF genom fem konsekutiva syntesreaktioner. Produkter från varje reaktionsteg analyserades kvalitativt och/eller kvantitativt för att verifiera närvaron av samtliga introducerade grupper. Dessa analyser omfattade FTIR-spektroskopi, ζ-potential, titreringar samt SEM-EDS. Resultaten indikerar det framgångsrika alstrandet av zwitterjonisk acetylerad CNF, som mest troligen är kapabel till att hämma passagen av tungmetallerjoner.

  • 46.
    Sabzehzar, Hooman
    KTH, Skolan för industriell teknik och management (ITM), Industriell ekonomi och organisation (Inst.).
    The role of brand equity in B2B: A comparative cross industrial analysis2012Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Many companies have exploited the power of brand equity in B2C markets as a source of competitive advantage. The trend in B2B, however, seems to be slightly different where many decision makers still believe that branding is not relevant to their business as it is to B2C.

    This paper investigates the role of brand equity in B2B businesses and shows how long-term investment in brand equity can change the rules of the game radically in favor of those B2B companies who have invested in their brand with a "holistic" approach which conform the overall strategy of the company. Caterpillar Inc. has been chosen as the case study and the role of its brand equity in its superior performance over its competitor, Komatsu Ltd, is investigated. The qualitative part of the research analyses the brand associations and the roles that these associations together with other brand elements play for Caterpillar and its customers. The quantitative part investigates two particular areas of recovery from market difficulties and efficiency in market communications and proves the role of higher brand equity in superior performance in recovery from market difficulties and marketing communications efficiency. The results are then tested further on the second case study which compares Intel to AMD.

    The results also open up new lines for further research on the subject both in depth and breadth where suggestions are made for generalizability of the research as well as determining the role of brand equity in companies' performances more precisely.

  • 47.
    Selamtzis, Andreas
    KTH, Skolan för elektroteknik och datavetenskap (EECS).
    Analyses of voice and glottographic signals in singing and speech2018Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Recent advances in machine learning and time series analysis techniques have brought new perspectives to a great number of scientific fields. This thesis contributes applications of such techniques to voice analysis, in an attempt to extract information on the vibration of the vocal folds as such, as well as on the radiated acoustic signal. The data that was analyzed in this work are acoustic recordings, electroglottographic (EGG) signals and transnasal high- speed videoendoscopic images. The data analysis techniques are primarily based on clustering, i.e., grouping of data based on similarity, and sample entropy analysis, i.e., quantifying the degree of irregularity in a given signal. The experiments were conducted so as to provide data for different types of vibratory behaviors (or vibratory states) of the vocal folds. Clustering was used in order to categorize in an unsupervised fashion these different vi- bratory states, based solely on the electroglottographic signal, or the glottal area waveform, or both. Sample entropy was utilized as an indicator of in- stabilities, when subjects produced voiced sounds using irregular vibratory patterns, such as register breaks, intermittent diplophonia, and other types of irregularities. The prominent role of sound pressure level and fundamental frequency motivated further study of the relationship between them and the shape of the electroglottographic waveform. Graphical representations were created to visualize the relationship between different vibratory behaviors with fundamental frequency and sound pressure level. The EGG waveform shape was seen to depend strongly on sound pressure level and somewhat less on fundamental frequency. In very soft phonation, the almost sinusoidal waveform of the EGG suggests that studying the EGG using clusters may give a better representation compared to conventional time-domain metrics. The paradigm of the clustering was later applied in synchronous recordings of electroglottogram and glottal area waveforms in professional tenor singers. Different vibratory states were classified successfully using clustering, and the electroglottogram was seen to be as good as the glottal area waveform for such a classification task. The last part of this work concerns voices from subjects with organic dysphonia. A study was dedicated to investigate how vowel context (sustained versus excerpted from speech) can affect the power of quantitative acoustic measures to discriminate dysphonic subjects from controls. Two acoustic voice quality measures were used: the cepstral peak prominence (smoothed) and sample entropy. The cepstral peak prominence (smoothed) showed better discriminatory power with excerpted vowels, while sample entropy with sustained vowels. Additionally, it was found that sample entropy was strongly correlated with cepstral peak prominence (smoothed) and with the perceptual quality of breathiness. 

  • 48.
    Selamtzis, Andreas
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH.
    Electroglottographic analysis of phonatory dynamics and states2014Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The human voice is a product of an intricate biophysical system. The complexity of this system enables a rich variety of possible sounds, but at the same time poses great challenges for quantitative voice analysis. For example, the vocal folds can vibrate in several different ways, leading to variations in the acoustic output. Because the vocal folds are relatively inaccessible, such variations are often difficult to account for. This work proposes a novel method for extracting non-invasively information on the vibratory state of the human vocal folds. Such information is important for creating a more complete voice analysis scheme. Invasive methods are undesirable because they often disturb the subjects and/or the studied phenomena, and they are also impractical in terms of accessibility and cost. A useful frame of reference for voice analysis is the Voice Range Profile (VRP). The 3 dimensional form of the VRP can be used to depict any phonatory metric over the 2 dimensional plane defined by the fundamental frequency of phonation (x-axis) and the sound pressure level (y-axis). The primary goal of this work was to incorporate information on the vibratory state of the vocal folds into the Voice Range Profile (e.g., as a color change). For this purpose, a novel method of analysis of the electroglottogram (EGG) was developed, using techniques from machine learning (clustering) and nonlinear time series analysis (sample entropy estimation). The analysis makes no prior assumptions on the nature of the EGG signal and does not rely on its absolute amplitude or frequency. Unlike time-domain methods, which typically define thresholds for quantifying EGG cycle metrics, the proposed method uses information from the entire cycle of each period. The analysis was applied in a variety of experimental conditions (constant vowel with different vibratory states, constant vibratory state and different vowels, constant vowel and vibratory state with varying lung volume) and the magnitude of effect on the EGG short-term spectrum was estimated for each of these conditions. It was found that the short-term spectrum of the EGG signal sufficed to discriminate between different phonatory configurations, such as modal and falsetto voice. It was found also that even supposedly purely articulatory changes could be traced in the spectrum of the EGG signal. Finally, possible pedagogical and clinical applications of the method are discussed.

  • 49.
    Selamtzis, Andreas
    et al.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Tal, musik och hörsel, TMH.
    Ternström, Sten
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Tal, musik och hörsel, TMH.
    Richter, Bernard
    Burk, Fabian
    Köberlein, Maria
    Echternach, Matthias
    A comparison of electroglottographic and glottal area waveforms for phonation type differentiation in male professional singers2018Manuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    This study investigates the use of glottographic signals (EGG and GAW) to study phonation in different vibratory states as produced by professionally trained singers. Six western classical tenors were asked to phonate pitch glides from modal to falsetto phonation, or modal to their stage voice above the passaggio (SVaP). For each pitch glide the sample entropy (SampEn) of the EGG signal was calculated to establish a “ground truth” for the performed phonation type; the cycles before the maximum SampEn peak were labeled as modal, and the cycles after the peak as falsetto, or SVaP. Three classifications of vibratory state were performed using clustering: one based only on the EGG, one based on the GAW, and one based on their combi- nation. The classification error rate (clustering vs ground truth) was on average smaller than 10%, for any of the three settings, revealing no special advantage of the GAW over EGG, and vice versa. The EGG-based time domain metric analysis revealed a larger contact quotient and larger normalized EGG derivative peak ratio in modal, compared to SVaP and falsetto. The glottographic waveform comparison of SVaP with falsetto and modal suggests that SVaP resembles more falsetto than modal, though with a larger contact quotient. 

  • 50.
    Singh, Sathya P.
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Material- och nanofysik, Funktionella material, FNM.
    Nikkam, Nader
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Material- och nanofysik, Funktionella material, FNM.
    Ghanbarpour, Morteza
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Tillämpad termodynamik och kylteknik.
    Toprak, Muhammet
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Material- och nanofysik, Funktionella material, FNM.
    Muhammed, Mamoun
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Material- och nanofysik, Funktionella material, FNM.
    Khodabandeh, Rahmatollah
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Tillämpad termodynamik och kylteknik.
    Design and Evaluation of Carbon Nanotube Based Nanofluids for Heat Transfer Applications2013Ingår i: MRS Spring 2013 Proceedings: Symposium on Nanoscale Heat Transport—From Fundamentals to Devices, Materials Research Society, 2013Konferensbidrag (Refereegranskat)
    Abstract [en]

    The present work investigates the fabrication, thermal conductivity (TC) and rheological properties of water based carbon nanotubes (CNTs) nanofluids (NFs) prepared using a two-step method. As-received (AR) CNTs heated and the effect of heat treatment was studied using X-ray diffraction and thermogravimetric analysis. The AR-CNTs and heat-treated CNTs (HT-CNTs) were dispersed with varying concentration of surface modifiers Gum Arabic (GA) and TritonX-100 (TX) respectively. It was found that heat treatment of CNTs effectively improved the TC and influenced rheological properties of NFs. Scanning electron microscopy analysis revealed TX modified NFs showed better dispersion ability compared to GA. Surface modification of the CNTs was confirmed by Fourier Transformation Infrared (FTIR) analysis. Zeta potential measurement showed the stability region for GA modified NFs in the pH range of 5-11, whereas pH was between 9.5-10 for TX NFs. The concentration of surface modifier plays an extensive role on both TC and rheological behavior of NFs. A maximum TC enhancement of 10% with increases in viscosity around 2% for TX based HT-CNTs NFs was measured. Finally comparison of experimental TC results with the predicted values obtained from a model demonstrated inadequacy of the predictive model for CNT NFs system.

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