Method for in-situ balancing of rotatives by use of an on-the-fly pulsating material removal process

Balancing rotating systems is a challenging task, which requires (dis)assembly of the system to enable mass adjustments; thus the development of a method to balance rotatives in-situ (i.e. without disassembly) using pulsed laser ablation (PLA) is a key technology enabler. PLA for in-situ balancing offers inherent advantages of an adjustable frequency (to match that of the rotating part) and variable pulse energy (to control the mass removal). This thesis presents a novel methodology for balancing components in-situ using PLA in a controlled and automated manner. The method utilises a sensor to measure the acceleration of the rigid rotor-bearing system. After signal conditioning using an adaptive peak filter (i.e. an inverted notch filter), a developed peak detection algorithm determines the maxima of the signal to find the angular imbalance position. If corrective action is necessary, PLA occurs. The method accounts for the time delays in the laser system and electronic circuit. Validation on a rotating part showed a PLA targeting accuracy of < 50μm and a precision of < 30μm; the feasibility of the method was confirmed using a simulation and by balancing a rotor with an arbitrary added imbalance. A concept, which was devised to optimise the PLA strategy for removing imbalances, bases on a novel combination of an analytical and machine learning approach. It determines the optimum process parameters of an ablated feature with a specified shape and volume. Additionally, an error budget for the method has been developed. The concept has been validated and shown to be accurate to < 4mg. The error budget could account for variations. It has been shown long features in the circumferential direction of the part increase the material removal rate with only minor increases in the error magnitude. To conclude, a concept for the integration of the two developed models is presented

Method for in-situ balancing of rotatives by use of an on-the-fly pulsating material removal process

Balancing rotating systems is a challenging task, which requires (dis)assembly of the system to enable mass adjustments; thus the development of a method to balance rotatives in-situ (i.e. without disassembly) using pulsed laser ablation (PLA) is a key technology enabler. PLA for in-situ balancing offers inherent advantages of an adjustable frequency (to match that of the rotating part) and variable pulse energy (to control the mass removal). This thesis presents a novel methodology for balancing components in-situ using PLA in a controlled and automated manner. The method utilises a sensor to measure the acceleration of the rigid rotor-bearing system. After signal conditioning using an adaptive peak filter (i.e. an inverted notch filter), a developed peak detection algorithm determines the maxima of the signal to find the angular imbalance position. If corrective action is necessary, PLA occurs. The method accounts for the time delays in the laser system and electronic circuit. Validation on a rotating part showed a PLA targeting accuracy of < 50μm and a precision of < 30μm; the feasibility of the method was confirmed using a simulation and by balancing a rotor with an arbitrary added imbalance. A concept, which was devised to optimise the PLA strategy for removing imbalances, bases on a novel combination of an analytical and machine learning approach. It determines the optimum process parameters of an ablated feature with a specified shape and volume. Additionally, an error budget for the method has been developed. The concept has been validated and shown to be accurate to < 4mg. The error budget could account for variations. It has been shown long features in the circumferential direction of the part increase the material removal rate with only minor increases in the error magnitude. To conclude, a concept for the integration of the two developed models is presented

Measurement of deeply virtual Compton scattering at HERA

The cross-section for deeply virtual Compton scattering in the reaction ep → eγp has been measured with the ZEUS detector at HERA using integrated luminosities of 95.0 pb-1 of e+p and 16.7 pb-1 of e-p collisions. Differential cross-sections are presented as a function of the exchanged-photon virtuality, Q2, and the centre-of-mass energy, W, of the γ*p system in the region 5 &lt; Q2 &lt; 100 GeV2 and 40 &lt; W &lt; 140 GeV. The measured cross-sections rise steeply with increasing W. The measurements are compared to QCD-based calculations. © 2003 Elsevier B.V. All rights reserved

Проблемы использования методов дерматоглифики в раскрытии и расследовании преступлений

The production rates and substructure of jets have been studied in charged current deep inelastic e(+)p scattering for Q(2) > 200 GeV(2) with the ZEUS detector at HERA using an integrated luminosity of 110.5 pb(-1). Inclusive jet cross sections are presented for jets with transverse energies E(T)(jet) > 14 GeV and pseudorapidities in the range -1 14 Gev and a second jet having E(T)(jet) > 5 GeV. Measurements of the mean events with a jet having E, > 14 GeV and a second jet having E, subjet multiplicity, (n(sbj)), of the inclusive jet sample are presented. Predictions based on parton-shower Monte Carlo models and next-to-leading-order QCD calculations are compared to the measurements. The value of alpha(s) (M(z)), determined from (n(sbj)) at y(cut) = 10(-2) for jets with 25 < E(T)(jet) < 119 GeV, is alpha(s) (M(z)) = 0. 1202 +/- 0.0052 (stat.)(-0.0019)(+0.0060) (syst.)(-0.0053)(+0.0065) (th.). The mean subjet multiplicity as a function of Q(2) is found to be consistent with that measured in NC DlS

Observation of K\u3csub\u3eS\u3c/sub\u3e\u3csup\u3e0\u3c/sup\u3eK\u3csub\u3eS\u3c/sub\u3e\u3csup\u3e0\u3c/sup\u3e Resonances in Deep Inelastic Scattering at HERA

Inclusive Ks0Ks0 production in deep inelastic ep scattering at HERA has been studied with the ZEUS detector using an integrated luminosity of 120 pb-1. Two states are observed at masses of 1537-8-9 MeV and 1726 ± 7 MeV, as well as an enhancement around 1300 MeV. The state at 1537 MeV is consistent with the well established f′2(1525). The state at 1726 MeV may be the glueball candidate f0(1710). However, it\u27s width of 38 -14-20 MeV is narrower than 125 ± 10 MeV observed by previous experiments for the f0(1710). © 2003 Elsevier B.V. All rights reserved

Measurement of the open-charm contribution to the diffractive proton structure function

Production of D(*+/-)(2010) mesons in diffractive deep inelastic scattering has been measured with the ZEUS detector at HERA using an integrated luminosity of 82 pb(-1). Diffractive events were identified by the presence of a large rapidity gap in the final state. Differential cross sections have been measured in the kinematic region 1.5 1.5 GeV and \eta(D(*+/-))\ < 1.5. The measured cross sections are compared to theoretical predictions. The results are presented in terms of the open-charm contribution to the diffractive proton structure function. The data demonstrate a strong sensitivity to the diffractive parton densities