@phdthesis{Makuch2007,
  author    = {Makuch, Martin},
  title     = {Circumplanetary dust dynamics : application to Martian dust tori and Enceladus dust plumes},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-14404},
  school      = {Universit{\"a}t Potsdam},
  year      = {2007},
  abstract  = {Our Solar system contains a large amount of dust, containing valuable information about our close cosmic environment. If created in a planet's system, the particles stay predominantly in its vicinity and can form extended dust envelopes, tori or rings around them. A fascinating example of these complexes are Saturnian rings containing a wide range of particles sizes from house-size objects in the main rings up to micron-sized grains constituting the E ring. Other example are ring systems in general, containing a large fraction of dust or also the putative dust-tori surrounding the planet Mars. The dynamical life'' of such circumplanetary dust populations is the main subject of our study. In this thesis a general model of creation, dynamics and death'' of circumplanetary dust is developed. Endogenic and exogenic processes creating dust at atmosphereless bodies are presented. Then, we describe the main forces influencing the particle dynamics and study dynamical responses induced by stochastic fluctuations. In order to estimate the properties of steady-state population of considered dust complex, the grain mean lifetime as a result of a balance of dust creation, life'' and loss mechanisms is determined. The latter strongly depends on the surrounding environment, the particle properties and its dynamical history. The presented model can be readily applied to study any circumplanetary dust complex. As an example we study dynamics of two dust populations in the Solar system. First we explore the dynamics of particles, ejected from Martian moon Deimos by impacts of micrometeoroids, which should form a putative tori along the orbit of the moon. The long-term influence of indirect component of radiation pressure, the Poynting-Robertson drag gives rise in significant change of torus geometry. Furthermore, the action of radiation pressure on rotating non-spherical dust particles results in stochastic dispersion of initially confined ensemble of particles, which causes decrease of particle number densities and corresponding optical depth of the torus. Second, we investigate the dust dynamics in the vicinity of Saturnian moon Enceladus. During three flybys of the Cassini spacecraft with Enceladus, the on-board dust detector registered a micron-sized dust population around the moon. Surprisingly, the peak of the measured impact rate occurred 1 minute before the closest approach of the spacecraft to the moon. This asymmetry of the measured rate can be associated with locally enhanced dust production near Enceladus south pole. Other Cassini instruments also detected evidence of geophysical activity in the south polar region of the moon: high surface temperature and extended plumes of gas and dust leaving the surface. Comparison of our results with this in situ measurements reveals that the south polar ejecta may provide the dominant source of particles sustaining the Saturn's E ring.},
  language  = {en}
}
@misc{NoirayIskarousWhalen2014,
  author    = {Noiray, Aude and Iskarous, Khalil and Whalen, Douglas H.},
  title     = {Variability in English vowels is comparable in articulation and acoustics},
  series = {Postprints der Universit{\"a}t Potsdam : Philosophische Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Philosophische Reihe},
  number    = {137},
  issn      = {1866-8380},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-399196},
  pages     = {18},
  year      = {2014},
  abstract  = {The nature of the links between speech production and perception has been the subject of longstanding debate. The present study investigated the articulatory parameter of tongue height and the acoustic F1-F0 difference for the phonological distinction of vowel height in American English front vowels. Multiple repetitions of /i, ɪ, e, ɛ, {\ae}/ in [(h)Vd] sequences were recorded in seven adult speakers. Articulatory (ultrasound) and acoustic data were collected simultaneously to provide a direct comparison of variability in vowel production in both domains. Results showed idiosyncratic patterns of articulation for contrasting the three front vowel pairs /i-ɪ/, /e-ɛ/, and /ɛ-{\ae}/ across subjects, with the degree of variability in vowel articulation comparable to that observed in the acoustics for all seven participants. However, contrary to what was expected, some speakers showed reversals for tongue height for /ɪ/-/e/ that were also reflected in acoustics, with F1 higher for /ɪ/ than for /e/. The data suggest the phonological distinction of height is conveyed via speaker-specific articulatory-acoustic patterns that do not strictly match features descriptions. However, the acoustic signal is faithful to the articulatory configuration that generated it, carrying the crucial information for perceptual contrast.},
  language  = {en}
}