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Road construction is important to make transports safe and sustainable. To compact asphalt an amount of energy needs to be conducted into the material either by static pressure or dynamic vibrations. An asphalt-roller compact the material and increases its load-bearing capacity. An eccentric shaft that generates vibrations is attached inside the roller drums. The shaft has two modes, varying between high eccentricity with slower pulses and low eccentricity with faster pulses. The study has been performed with the purpose to decrease the mass moment of inertia by redesigning the present eccentric shaft and verifying the new concepts with linear and non-linear FEM simulations. The new models were to have the same functional properties as the present eccentric shaft.  The current cross-section of the shaft was changed to a cross-section of a circle in the periphery. This was done by adding all features in new geometry to a simple shaft base and creating an analysis chain. To create the new lengthwise design brainstorming was used to generate ideas. The ideas were then sorted by using a Pugh matrix. CAD was used to model the concepts with the desired eccentric properties. Simulation in FEM software was used to acquire information about the behaviors during operation. Academic validation and useful information have been gathered by doing a literature review.  Two resulting concepts with properties fulfilling the prevailing restrictions. The circular cross-section in the periphery was adapted and the eccentric properties were kept. The simulation results from FEM software ended satisfactorily within limits for both execution in steel and ductile iron. For both concepts the mass moment of inertia was minimized, with 40.5 % in steel and in ductile iron with 42.0 % and 42.6 %.  An analysis chain has been performed showing that a cross-section with a circular geometry is optimal when the intention is to minimize the mass moment of inertia. It is possible to minimize the mass moment of inertia without negatively affecting the eccentric properties. The lengthwise design of a shaft with eccentric properties has been studied and simulated. Two concepts with varied lengthwise designs have been created with conserved eccentric properties and significantly decreased mass moment of inertia. The concepts can compose a good basis to continue investigating the lengthwise design which hopefully ends in a manufacturable eccentric shaft that contributes to environmental asphalt construction with low energy usage. / Tillverkning av vägar är viktigt för att transporter ska kunna utföras på ett säkert och hållbart sätt. För att packa asfalt behövs en mängd energi överföras till materialet genom statiskt tryck eller dynamiska vibrationer. En asfaltsvält packar materialet och ökar dess belastningsförmåga. En excentrisk axel som genererar vibrationer sitter inuti trummorna på välten. Denna axel har två lägen som varierar mellan att ha hög excentricitet med lägre puls samt låg excentricitet med högre puls.  Studien har genomförts med syftet att minska den nuvarande excenteraxelns masströghetsmoment genom att designa om den samt verifiera nya koncept med linjära och icke-linjära FEM beräkningar. De nya modellerna skulle behålla samma funktionella egenskaper som den nuvarande excenteraxeln. Det nuvarande tvärsnittet i XY-planet ändrades till en cirkel i rotationsaxlens periferi, genom att lägga till alla funktioner med nya tvärsnitt på en enkel axelbas i en analyskedja. En ny design i längsled påbörjades med brainstorming för att generera nya idéer. Idéerna sorterades sedan med hjälp av en Pugh-matris. Koncepten modellerades sedan med önskade excentriska egenskaper i CAD. FEM-mjukvara användes för att simulera koncepten och samla information om beteenden under körning. Akademisk validering och användbar information samlades in i en litteraturstudie.  Arbetet resulterade i två koncept med egenskaper som uppfyllde rådande krav. Det cirkulära tvärsnittet i periferin behölls och likaså de excentriska egenskaperna. FEM resultaten visade sig hamna tillfredsställande under gränserna med materialen stål och segjärn. För båda koncepten minskade masströghetsmomentet varav 40.5 % i stål och 42.0 % respektive 42.6 % i segjärn.  En analyskedja har genomförts som visat att ett tvärsnitt av en cirkel i periferi är optimalt med intentionen att minska masströghetsmomentet. Det är möjligt att minska masströghetsmomentet utan att påverka de excentriska egenskaperna negativt. Designen längs med en axel med excentriska egenskaper har studerats och simulerat. Två koncept med varierad design har modellerats, koncepten har behållna excentriska egenskaper och betydligt minskat masströghetsmoment. Koncepten kan utgöra gott underlag för fortsatt undersökning av designen i längdled. Förhoppningsvis kan det i sin tur resultera i en tillverkningsbar excentrisk axel som bidrar till miljövänligare asfaltskonstruktion med låg energiåtgång.

Hearing loss of various types is increasingly plaguing our modern world (Geneva: World Health Organization 2018). As the life expectancy increased in the industrialized world, age-related hearing loss (ARHL) has become more prevalent. The wars and terrorism of the modern world also created a significant body of blast-induced hearing loss (BIHL) patients. Both types of hearing loss present significant challenges for listeners even at suprathreshold sound levels. However, increasing bodies of clinical and laboratory evidence have suggested that the difficulties in the processing of time-varying auditory features in speech and other natural sounds may not be sufficiently diagnosed by threshold changes and simple auditory electrophysiological measures (Snell and Frisina 2000; Saunders et al. 2015; Bressler et al. 2017; Guest et al. 2018).<br>Studies have emphasized that excitatory/inhibitory neurotransmission imbalance plays important roles in ARHL (Caspary et al. 2008) and may also be key in BIHL, as hinted by the strong presence of GABA regulation in non-blast TBI (O’Dell et al. 2000; Cantu et al. 2015; Guerriero et al. 2015). The current studies focus on age-related and blast-induced hearing deficits by examining changes in the processing of simple, brief stimuli and complex, sustained, temporally modulated sounds.<br>Through post hoc circular analysis of single-unit, in vivo recording of young and aged inferior colliculus (IC) neurons responding to amplitude modulation (AM) stimuli and modulation depth changes, we observed evidence of central compensation in the IC manifesting as increased sensitivity to presynaptic input, which was measured via local field potentials (LFPs). We also found decreased sensitivity to decreasing modulation depth. Age-related central gain in the IC single units, while preserving and even overcompensating for temporal phase coding in the form of vector strength, was unable to make up for the loss of envelope shape coding.<br>Through careful, longitudinal measurements of auditory evoked potential (AEP) responses towards simple sounds, AM and speech-like iterated rippled noise (IRN), we documented the development and recovery of BIHL induced by a single mild blast in a previously established (Song et al. 2015; Walls et al. 2016; Race et al. 2017) rat blast model over the course of two months. We identified crucial acute (day 1-4 post-exposure) and early recovery (day 7-14) time windows in which drastic changes in electrophysiology take place. Challenging conditions and broadband, speech-like stimuli can better elucidate mild bTBI-induced auditory deficits during the sub-acute period. The anatomical significance of the aforementioned time windows was demonstrated with immunohistochemistry methods, showing two distinct waves of GABA inhibitory transmission changes taking place in the auditory brainstem, the IC, and the auditory thalamus. These changes were in addition to axonal and oxidative damage evident in the acute phase. We examined the roles and patterns of excitatory/inhibitory imbalance in BIHL, its distinction compared to that of ARHL, and demonstrated the complexity of its electrophysiological consequences. Blast traumatizes the peripheral auditory system and auditory brainstem, evident through membrane damage and acrolein-mediated oxidative stress. These initial traumas kickstart a unique, interlocking cascade of excitatory/inhibitory imbalances along the auditory neuraxis that is more complex and individually varied than the gradual, non-traumatic degradations in ARHL. Systemic treatment with the FDA-approved acrolein scavenger Hydralazine (HZ) was attempted with limited effects.<br>Taken together, the current study provided insights into the similarities and distinctions between the mechanisms of ARHL and BIHL and called for innovative and individual diagnostic and therapeutic measures.<br>

The mesopause region monthly mean winds and semidiurnal tidal amplitudes and phases over Central Europe in the height range between 85-105 km have been measured at Collm Observatory continuously since September 1982. The regular annual cycle of the semidiurnal tidal amplitudes show in all cases maximum values during late August and September. In contrast to that, in autumn 2002 no enhancement of the tidal amplitudes was measured, while the autumn tidal phase transition occurred unusually early. The unexpected behaviour of the semidiurnal tides seems to be connected with a very early autumn transition of the zonal prevailing winds. This suggests that in 2002 the zonal mean winds influence the tidal propagation in a different way than usual. / Die monatlich gemittelten Grundwinde und halbtägigen Gezeiten werden am Collm seit September 1982 im Höhenbereich zwischen 85-105 km gemessen. Der normale Jahresgang der halbtägigen Gezeiten zeigt maximale Amplituden im Winter und vor allem im Spätsommer/Herbst. Dieses Maximum ist im Jahre 2002 nicht zu verzeichnen. Dies ist begleitet von einer ungewöhnlich frühen Phasenänderung von der Sommer- zur Winterposition. Das Verhalten der Gezeiten scheint mit einer sehr frühen Änderung des zonalen Grundwindes vom Sommer- zum Winterregime verbunden zu sein, so dass die Anomalie der mittleren Zirkulation für die Gezeitenanomalie verantwortlich zu sein scheint.

Today represents vibration analysis an inseparable part of the product design, especially aeronautical components, machine tools etc. One of the vibration analysis methods is the so-called modal analysis, which determines the modal parameters of the researched structure. This paper deals with a comparison of two commonly used approaches, namely „Single Input Multiple Output“ (SIMO) and „Multiple Input Multiple Output“ analysis (MIMO). A MIMO procedure of measurement is developed and discussed. Both analyses are executed by the same conditions on the milling machine based on parallel kinematics in order to objective comparison. The results show that the choice of the so-called refer-ence points is very important. In case both references are appropriately selected, the MIMO analysis gives better results that the SIMO one.

The electromagnetic form factors in elastic electron-proton scattering are used to determine the finite size of the proton. Through the use of Feynman Diagrams and Fermi's "golden rule", several key results for cross sections of elastic electron scattering will be re-derived. This will ultimately lead to the calculation for the Rosenbluth formula, that describes in detail the process of electron-proton scattering. Furthermore, the process used for determining the size of the proton from the form factors will be shown. In addition, a recent paper by R. Jaffe, which argues the validity of this process, will be discussed in detail. / Physics

Understanding the effects of uncertainty on modeling has seen an increased focus as engineering disciplines rely more heavily on computational modeling of complex physical processes to predict system performance and make informed engineering decisions. These computational methods often use simplified models and assumptions with models calibrated using uncertain, averaged experimental data. This commonplace method ignores the effects of uncertainty on the variation of modeling output. Qualitatively, uncertainty is the possibility of error existing from experiment to experiment, from model to model, or from experiment to model. Quantitatively, uncertainty quantification (UQ) methodologies seek to determine the how variable an engineering system is when subjected to variation in the factors that control it. Often performed in conjunction, sensitivity analysis (SA) methods seek to describe what model factor contributes the most to variation in model output. UQ and SA methodologies were employed in the analysis of the Modified Embedded Atom Method (MEAM) model for a pure aluminum, a microstructure sensitive fatigue crack growth model for polycarbonate, and the MultiStage Fatigue (MSF) model for AZ31 magnesium alloy. For the MEAM model, local uncertainty and sensitivity measures were investigated for the purpose of improving model calibrations. In polycarbonate fatigue crack growth, a Monte Carlo method is implemented in code and employed to investigate how variations in model input factors effect fatigue crack growth predictions. Lastly, in the analysis of fatigue life predictions with the MSF model for AZ31, the expected fatigue performance range due to variation in experimental parameters is investigated using both Monte Carlo Simple Random Sampling (MCSRS) methods and the estimation of first order effects indices using the Fourier Amplitude Sensitivity Test (FAST) method.

With the development and expansion of traffic systems, problems associated with ground vibrations have required increased attention. Increasing vehicle loads,traffic volumes, and aging roads and railways,vibrations induced by traffic are gradually becoming acrucialproblem.Traffic induced vibrations have much smaller amplitude than those considered in seismic design, but may nevertheless cause annoyance for humans, damage to building, disturb sensitive equipment such as measurements devices, automated manufacturing in factories, etc. It is the purposeto study the effects of the in-filled trench (cell foamis usedas in-filled material in the test)as a wave barrieron the ground vibrationunder excitation of amechanicalvibrator(with an electric motor) in small scale laboratory tests. Laboratory methods are utilized for investigating the influence of cell foam on vibrations in sand by conducting vertical vibration tests with different thickness of cell foam.It is concluded that cell foam used as a wave barriermaterialis significantly working forhighfrequency rangeand for low frequency range the effect is not so effective and obvious.

京都大学 / 新制・課程博士 / 博士(理学) / 甲第24412号 / 理博第4911号 / 新制||理||1702(附属図書館) / 京都大学大学院理学研究科物理学・宇宙物理学専攻 / (主査)教授 橋本 幸士, 准教授 福間 將文, 教授 杉本 茂樹 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM

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