Search results

This paper presents a measurement of the polarisation of W bosons from tt¯ decays, reconstructed in events with one high-pT lepton and at least four jets. Data from pp collisions at the LHC were collected at s = 8 TeV and correspond to an integrated luminosity of 20.2 fb- 1. The angle θ∗ between the b-quark from the top quark decay and a direct W boson decay product in the W boson rest frame is se

This paper describes an interactive tool focused on teaching and learning basic concepts on multivariable control systems. Most industrial processes are represented by multivariable systems and thus the teaching and learning of basic concepts on multivariable control is a key factor in control engineering education. In this sense, the interactive tool presented in this paper is aimed to introduce

This paper describes an interactive tool focused on teaching and learning basic concepts about modelling and identification. Modelling and identification play fundamental roles in the field of automatic control, since it is not possible to perform a control system design without having a model describing the dynamics of the process to be controlled. The tool presented in this work is dedicated to

Event-based control is a promising alternative to time-triggered control, especially for systems with limited computation and communication capacities. In the paper, the architecture of a general structure for event-based control is presented. The resulting system has many interesting properties. For instance, a constant load disturbance will typically make the process output oscillate according t

This paper describes a collection of interactive learning modules for PID control based on the graphical spread sheet metaphor. The modules are designed to speed up learning and to enhance understanding of the behaviour of loops with PID controllers. The modules are implemented in Sysquake, a Matlab dialect with strong support of interaction. Executable versions of the modules for Mac and PC are a

The Kalman filter is the optimal state observer in the case of linear dynamics and Gaussian noise. In this paper, the observer problem is studied when process noise and measurements are generalized from Gaussian to log-concave. This generalization is of interest for example in the case where observations only give information that the signal is in a given range. It turns out that the optimal obse

High performance of an explosive compound with respect to afterburning requires sufficient combustible properties of the explosive, and a careful determination of the most appropriate charge positioning to achieve the desired afterburning effect. Understanding the physical processes of post-detonation afterburning and how these are affected by the surroundings, e.g. the Height of Burst (HoB), faciHigh performance of an explosive compound with respect to afterburning requires sufficient combustible properties of the explosive, and a careful determination of the most appropriate charge positioning to achieve the desired afterburning effect. Understanding the physical processes of post-detonation afterburning and how these are affected by the surroundings, e.g. the Height of Burst (HoB), faci

Programmable Logic Controllers (PLCs) play an important role for integration of hardware and software in industrial robot cells. In this paper we propose a semantic grounding of the Sequential Function Charts (SFC) notation for specification of PLC programs. Our semantic grounding is expressed in the OWL semantic language and forms part of our semantic robot framework, called KIF (Knowledge Integr

We present the first measurement of the two-particle transverse momentum differential correlation function, P2≡ ΔpTΔpT/ pT2, in Pb-Pb collisions at sNN=2.76 TeV. Results for P2 are reported as a function of the relative pseudorapidity (Δη) and azimuthal angle (Δφ) between two particles for different collision centralities. The Δφ dependence is found to be largely independent of Δη for |Δη|≥0.9. In

We report on experiments that investigate the dynamics, identification and control of thermoacoustic phenomena in a Rijke tube apparatus. These experiments are relatively simple to construct and conduct in a typical, well-equipped undergraduate controls laboratory, yet allow for the exploration of rich and coupled acoustic and thermal dynamics, the associated thermoacoustic instabilities, and the

This paper treats the trade-off between robustness, load disturbance attenuation, and measurement noise injection for PI and PID control using Lambda, SIMC, and AMIGO tuning. The effects of measurement noise are characterized by SDU, which is a measure of noise activity analogous to the IAE commonly used to characterize performance of load disturbance response. Simple design rules to choose the fi

The relay autotuner for PID control is based on the simple idea of investigating process dynamics by the oscillation obtained when the PID controller is replaced by a relay unction. In this paper an asymmetric relay function is used, which provides an equation for the static gain of the process. A method to find the normalized time delay is proposed and the benefits of this is discussed. Ways to f

Hundreds of PID design methods are available in literature. Many of them are very similar and sometimes it is not straightforward to understand their purposes. This paper presents an interactive software tool to help in the study and understanding of several wellknown PID tuning rules. Frequency- and time-domain responses are analyzed in order to show the robustness and performance properties of e

This paper presents an interactive software tool for basic and advanced concepts of feedforward control. The ideal compensator is analyzed to show how the effects of the load disturbances are eliminated from the process output. Furthermore, it is also shown that the ideal compensator is seldom realizable, since the compensator may be non-causal, it may be unstable, it may have infinite high-freque

The azimuthal correlations of D mesons with charged particles were measured with the ALICE apparatus in pp collisions at s=7TeV and p–Pb collisions at sNN=5.02TeV at the Large Hadron Collider. D 0, D +, and D ∗ + mesons and their charge conjugates with transverse momentum 3