98 research outputs found
Advanced Parameterisation of Online Handwriting in Writers with Graphomotor Disabilities
Grafomotorick© obte (GD) vraznÄ ovlivuj kvalitu ivota kolnm vÄkem poÄnajc, kde se vyvjej grafomotorick© schopnosti, a do dchodov©ho vÄku. VÄasn diagnza tÄchto obt a terapeutick zsah maj velk vznam k jejich zlepen. Vzhledem k tomu, e GD souvis z vcermi symptomy v oblasti kinematiky, zkladn kinematick© parametry jako rychlost, zrychlen a vih prokzaly efektivn kvantizaci tÄchto symptom. Objektivn vpoÄetn syst©m podpory rozhodovn pro identifikaci a vyeten GD vak nen dostupn. A proto je hlavnm clem m© disertaÄn prce vzkum pokroÄil© metody parametrizace online psma pro analzu GD se specilnm zamÄenm na vyuit metod zlomkov©ho kalkulu. Tato prce je prvn, kter experimentuje s vyuitm derivac neceloÄseln©ho du (FD) pro analzu GD pomoc online psma zskan©ho od pacient s Parkinsonovou nemoc a u dÄt kolnho vÄku. Byla navrena a evaluovna nov metoda parametrizace online psma zaloena na FD vyuitm Grnwald-Letnikova pstupu. Bylo dokzno, e navren metoda vznamnÄ zlepuje diskriminaÄn slu a deskriptivn schopnosti v oblasti Parkinsonick© dysgrafie. StejnÄ tak metoda pozitivnÄ ovlivnila i nejmodernÄj techniky v oblasti analzy GD u dÄt kolnho vÄku. Vyvinut parametrizace byla optimalizovna s ohledem na vpoÄetn nroÄnost (a o 80 %) a tak© na vyladÄn du FD. Ke konci prce byly porovnny vcer© pstupy vpoÄtu FD, jmenovitÄ Riemann-Liouvillv, Caputv spoleÄnÄ z Grnwald-Letnikovm pstupem za Äelem identifikace tÄch nejvhodnÄjch pro jednotliv© oblasti analzy GD.Graphomotor disabilities (GD) significantly affect the quality of life beginning from the school-age, when the graphomotor skills are developed, until the elderly age. The timely diagnosis of these difficulties and therapeutic interventions are of great importance. As GD are associated with several symptoms in the field of kinematics, the basic kinematic features such as velocity, acceleration, and jerk were proved to effectively quantify these symptoms. Nevertheless, an objective computerized decision support system for the identification and assessment of GD is still missing. Therefore, the main objective of my dissertation is the research of an advanced online handwriting parametrization utilized in the field of GD analysis, with a special focus on methods based on fractional calculus. This work is the first to experiment with fractional-order derivatives (FD) in the GD analysis by online handwriting of Parkinsonâs disease (PD) patients and school-age children. A new online handwriting parametrization technique based on the Grnwald-Letnikov approach of FD has been proposed and evaluated. In the field of PD dysgraphia, a significant improvement in the discrimination power and descriptive abilities was proven. Similarly, the proposed methodology improved current state-of-the-art techniques of GD analysis in school-aged children. The newly designed parametrization has been optimized in the scope of the computational performance (up to 80 %) as well as in FD order fine-tuning. Finally, various FD-approaches were compared, namely Riemann-Liouville, Caputoâs, together with Grnwald-Letnikov approximation to identify the most suitable approach for particular areas of GD analysis.
Measurement and Interpretation of Fermion-Pair Production at LEP energies above the Z Resonance
This paper presents DELPHI measurements and interpretations of
cross-sections, forward-backward asymmetries, and angular distributions, for
the e+e- -> ffbar process for centre-of-mass energies above the Z resonance,
from sqrt(s) ~ 130 - 207 GeV at the LEP collider. The measurements are
consistent with the predictions of the Standard Model and are used to study a
variety of models including the S-Matrix ansatz for e+e- -> ffbar scattering
and several models which include physics beyond the Standard Model: the
exchange of Z' bosons, contact interactions between fermions, the exchange of
gravitons in large extra dimensions and the exchange of sneutrino in R-parity
violating supersymmetry.Comment: 79 pages, 16 figures, Accepted by Eur. Phys. J.
A Determination of the Centre-of-Mass Energy at LEP2 using Radiative 2-fermion Events
Using e+e- -> mu+mu-(gamma) and e+e- -> qqbar(gamma) events radiative to the
Z pole, DELPHI has determined the centre-of-mass energy, sqrt{s}, using energy
and momentum constraint methods. The results are expressed as deviations from
the nominal LEP centre-of-mass energy, measured using other techniques. The
results are found to be compatible with the LEP Energy Working Group estimates
for a combination of the 1997 to 2000 data sets.Comment: 20 pages, 6 figures, Accepted by Eur. Phys. J.
A Measurement of the Tau Hadronic Branching Ratios
The exclusive and semi-exclusive branching ratios of the tau lepton hadronic
decay modes (h- v_t, h- pi0 v_t, h- pi0 pi0 v_t, h- \geq 2pi0 v_t, h- \geq 3pi0
v_t, 2h- h+ v_t, 2h- h+ pi0 v_t, 2h- h+ \geq 2pi0 v_t, 3h- 2h+ v_t and 3h- 2h+
\geq 1pi0 v_t) were measured with data from the DELPHI detector at LEP.Comment: 53 pages, 18 figures, Accepted by Eur. Phys. J.
Study of double-tagged gamma gamma events at LEPII
Double-tagged interactions of photons with virtualities Q^2 between 10 GeV^2
and 200 GeV^2 are studied with the data collected by DELPHI at LEPII from 1998
to 2000, corresponding to an integrated luminosity of 550 pb^{-1}. The gam*
gam* -> mu+mu- data agree with QED predictions. The cross-section of the
reaction gam* gam* -> hadrons is measured and compared to the LO and NLO BFKL
calculations.Comment: 17 pages, 9 figures, Accepted by Eur. Phys. J.
Study of the Dependence of Direct Soft Photon Production on the Jet Characteristics in Hadronic Z^0 Decays
40 pages, 10 figures, Accepted by Eur. Phys. J. CAn analysis of the direct soft photon production rate as a function of the parent jet characteristics is presented, based on hadronic events collected by the DELPHI experiment at LEP1. The dependences of the photon rates on the jet kinematic characteristics (momentum, mass, etc.) and on the jet charged, neutral and total hadron multiplicities are reported. Up to a scale factor of about four, which characterizes the overall value of the soft photon excess, a similarity of the observed soft photon behaviour to that of the inner hadronic bremsstrahlung predictions is found for the momentum, mass, and jet charged multiplicity dependences. However for the dependence of the soft photon rate on the jet neutral and total hadron multiplicities a prominent difference is found for the observed soft photon signal as compared to the expected bremsstrahlung from final state hadrons. The observed linear increase of the soft photon production rate with the jet total hadron multiplicity and its strong dependence on the jet neutral multiplicity suggest that the rate is proportional to the number of quark pairs produced in the fragmentation process, with the neutral pairs being more effectively radiating than the charged ones.Peer reviewe
Measurements of CP-conserving trilinear gauge boson couplings WWV (V≡γ,Z) in e+e− collisions at LEP2
The data taken by Delphi at centre-of-mass energies between 189 and 209 GeV are used to place limits on the CP-conserving trilinear gauge boson couplings , λ γ and Δκ γ associated to W + W − and single W production at Lep2. Using data from the jj ℓ ν, jjjj, jjX and ℓ X final states, where j, ℓ and X represent a jet, a lepton and missing four-momentum, respectively, the following limits are set on the couplings when one parameter is allowed to vary and the others are set to their Standard Model values of zero: Results are also presented when two or three parameters are allowed to vary. All observations are consistent with the predictions of the Standard Model and supersede the previous results on these gauge coupling parameters published by Delphi. This paper is dedicated to the memory of Professor Paul Booth who was Delphi Deputy Spokesperson from 1989 to 1994. He played a key role in the final installation and commissioning of the Delphi detector as well as leading the Liverpool group for many years thereafter.Peer reviewe
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