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Hybrid Processes and Process Synergies: Optimisation and Integration of Membrane Processes

Membrane processes are often competing directly with conventional separation processes. The aim of this study is to highlight the potentials of combinations of membrane processes and conventional separation processes by the means of hybrid processes and process synergies. The concepts of hybrid processes and process synergies will be introduced and defined supported by industrial examples, e.g. th

LEPTO 6.5 - A Monte Carlo generator for deep inelastic lepton-nucleon scattering

Physics and programming aspects are discussed for a Fortran 77 Monte Carlo program to simulate complete events in deep inelastic lepton-nucleon scattering. The parton level interaction is based on the standard model electroweak cross sections, which are fully implemented in leading order for any lepton of arbitrary polarization, and different parametrizations of parton density functions can be use

Force, Fear and Consent to Marriage : Theory and Practice in Late Medieval Europe

In the last half of the twelfth century, canon law established the rule that a marriage could be declared invalid if the consent had been given through force or fear. This ruling was a natural consequence of the insistence on free consent as the only requirement for a valid marriage. It did, however, entail a number of both practical and theoretical problems. It could be difficult to prove force a

Differences between Monte Carlo models for DIS at small-χ and the relation to BFKL dynamics

The differences between two standard Monte Carlo models, LEPTO and ARIADNE, for deep inelastic scattering at small-χ is analysed in detail. It is shown that the difference arises from a 'unorthodox' suppression factor used in ARIADNE which replaces the normal ratio of parton densities. This gives rise to a factor that qualitatively is similar to what one would expect from BFKL dynamics for some ob

AROMA 2.2 - A Monte Carlo generator for heavy flavour events in ep collisions

A program to simulate the production of heavy quarks through the boson-gluon fusion process in e±p collisions is presented. The full electroweak structure of the electron-gluon interaction is taken into account as well as the masses of the produced heavy quarks. Higher order QCD radiation is treated using initial and final state parton showers, and hadronization is performed using the Lund string

Unified description of rapidity gaps and energy flows in DIS final states

We show that the 'orthogonal' characteristics of the observed rapidity gaps and large forward energy flows in deep inelastic scattering at HERA, can be described within a single framework. Our Monte Carlo model is based on perturbative QCD matrix elements and parton showers together with Lund string model hadronization, but has in addition a new mechanism for soft colour interactions which modifie

Quarkonium production at the Fermilab Tevatron through soft color interactions

The direct charmonium and bottomonium production rate observed at high [Formula presented] in [Formula presented] collisions at the Fermilab Tevatron is factors of 10 larger than predictions based on conventional perturbative QCD. We show that this excess can be accounted for by our model for soft color interactions, previously introduced to describe in a novel way the large rapidity gap events ob

Color evolution of 2 → 3 processes

The color structure needed for resummation of all colored 2 -> 3 processes is calculated using multiplet inspired s-channel bases. In this way the resulting matrices, describing the color structure, are guaranteed to obey simplifying symmetries.

Soft colour interactions as the origin of rapidity gaps in DIS

We introduce soft colour interactions as a novel mechanism to understand the observed events with large rapidity gaps in ep collisions at HERA. Colour exchanges between produced partons and colour-charges in the proton remnant modifies the colour structure for hadronization, such that colour singlet systems may appear well separated in rapidity. Our explicit model show characteristics of diffracti

Fixing the renormalization scheme in NNLO perturbative QCD using conformal limit arguments

We discuss how the renormalization scheme ambiguities in QCD can be fixed, when two observables are related, by requiring the coefficients in the perturbative expansion relating the two observables to have their conformal limit values, i.e., to be independent of the [Formula presented] function of the renormalized coupling. We show how the next-to-leading order BLM automatic scale-fixing method ca

Renormalisation scale uncertainty in the DIS 2+1 jet cross-section

The deep inelastic scattering 2+1 jet cross-section is a useful observable for precision tests of QCD, e.g. measuring the strong coupling constant αs. A consistent analysis requires a good understanding of the theoretical uncertainties and one of the fundamental ones in QCD is due to the renormalisation scheme and scale ambiguity. Different methods, which have been proposed to resolve the scale am

The strong coupling from ALEPH tau decays

We analyze some of the different determinations of αs(mτ 2) that can be found in the literature and the numerical impact of their possible weaknesses with the publicly available non-strange spectral function from ALEPH tau decays. We also introduce some novel approaches. We find very stable results and uncertainties dominated by the perturbative part. Our final value is αs(mτ 2)=0.328±0.013.

Heavy majorana neutrinos at ep colliders

Heavy Majorana neutrinos (N), predicted in various extensions of the standard model, are examined with respect to the present limits on their masses and mixings with ordinary leptons resulting in explicit examples of allowed values of interest for present and planned accelerator energies. The decay N→Zv is added to the previously available formalism and all dominating branching ratios are calculat

Determination of the QCD coupling from ALEPH τ decay data

We present a comprehensive study of the determination of the strong coupling from τ decay, using the most recent release of the experimental ALEPH data. We critically review all theoretical strategies used in previous works and put forward various novel approaches which allow one to study complementary aspects of the problem. We investigate the advantages and disadvantages of the different methods

Towards a holistic prioritization of climate-change risks for bridges

Although the projected changes in the climate include considerable uncertainties, especially with downscaling, there is irrefutable evidence that the climate is changing at an unprecedented and alarming rate. In recent studies, some of the potential climate-change risks on bridges have been identified. The sheer number of these potential risks provokes two questions. Firstly, for a certain risk of

The strong coupling from ALEPH tau decays

The strong coupling from ALEPH tau decays. We use the publically available non-strange spectral function from ALEPH tau decays to critically analyze the different determinations of αs(mτ2) that can be found in the literature and the numerical impact of their possible weaknesses. We also introduce some novel approaches. We find that perturbative uncertainties dominate. Our results with different ap