353 research outputs found
Les g�n�rations X et Y du Qu�bec, vraiment diff�rentes des pr�c�dentes ?
Many myths surround the Generation X members. Among them, the term "McJobs" is often used to describe the difficulties they have experienced on the labour market. It is justified to claim that they had a more complicated career path in comparison with other generations. However, what is really going on? Who are they really? This paper paints a portrait of both the Generation X, whose members were born between 1965 and 1975, and of their successors, the members of the Generation Y, who were born between 1975 and 1985. More precisely, this research will put emphasis on some highlights about the behaviour of the X and Y in Quebec contemporary society. This study will examine the themes of family, their attitude toward the labour market and saving. In order to have a better understanding of the extent of the differences observed, both groups will be compared with the baby boomers [who were divided in two subgroups, the old boomers (1945-1954) and the young boomers (1955-1964)]. The research findings coming from this analysis are numerous. We learn, among other things, that the X and the Y have fairly different behaviours than the baby boomers. Overall, these two birth cohorts had to go through a clearly less comfortable situation than the baby boomers. However, we also learn that the situation experienced by the young boomers, in some areas, is not very distant from what the Generation X is going through. However, the X will have to invest a lot in order to face retirement issues.Generation X, GenerationY, Unemployment, Demography, Savings
The complexity of existential quantification in concept languages
Much of the research on concept languages, also called terminological languages, has focused on the computational complexity of subsumption. The intractability results can be divided into two groups. First, it has been shown that extending the basic language FL- with constructs containing some form of logical disjunction leads to co-NP-hard subsumption problems. Second, adding negation to FL- makes subsumption PSPACE-complete. The main result of this paper is that extending FL- with unrestricted existential quantification makes subsumption NP-complete. This is the first proof of intractability for a concept language containing no construct expressing disjunction--whether explicitly or implicitly. Unrestricted existential quantification is therefore, alongside disjunction, a source of computational complexity in concept languages
Physics-guided neural networks for feedforward control with input-to-state-stability guarantees
The increasing demand on precision and throughput within high-precision mechatronics industries requires a new generation of feedforward controllers with higher accuracy than existing, physics-based feedforward controllers. As neural networks are universal approximators, they can in principle yield feedforward controllers with a higher accuracy, but suffer from bad extrapolation outside the training data set, which makes them unsafe for implementation in industry. Motivated by this, we develop a novel physics-guided neural network (PGNN) architecture that structurally merges a physics-based layer and a black-box neural layer in a single model. The parameters of the two layers are simultaneously identified, while a novel regularization cost function is used to prevent competition among layers and to preserve consistency of the physics-based parameters. Moreover, in order to ensure stability of PGNN feedforward controllers, we develop sufficient conditions for analyzing or imposing (during training) input-to-state stability of PGNNs, based on novel, less conservative Lipschitz bounds for neural networks. The developed PGNN feedforward control framework is validated on a real-life, high-precision industrial linear motor used in lithography machines, where it reaches a factor 2 improvement with respect to physics-based mass–friction feedforward and it significantly outperforms alternative neural network based feedforward controllers
Biometric differences between several populations of Cordulegaster boltonii (Odonata: Cordulegastridae) in Ibero-Maghrebian area
Biometric data of the exuviae of female larvae of the dragonfly Cordulegaster boltonii collected in Portugal, Spain and Morocco were analysed to determine whether the size of three exuvial structures measured differed depending on the geographic localities of the populations. Based on the results recorded for the 16 populations studied, head width was negatively correlated with latitude and the greatest length of the gonapophysis was recorded for the Iberian populations at the centre of this peninsula. Multivariate cluster analysis revealed a clear separation of the Moroccan population. A second cluster separated the southernmost population (Sierra Nevada) from the remaining Iberian populations. Four population groups were distinguished: those located in watercourses in the north and central area of the Iberian Peninsula, those in Iberian watercourses in the East and Middle South, the Sierra Nevada and North Morocco. Some of these results coincide with the results of genetic studies of other authors
Biosimilars : lights and shadows in rheumatology
In the last 10 years, the growing approval and marketing of biological agents has significantly ameliorated the outcomes of rheumatoid arthritis and spondyloarthritis patients suffering from active and refractory disease despite conventional treatments. As patent protection of many biopharmaceuticals will expire in the next years, biosimilars could be proximally introduced. Such agents could be marked only when they will be proven, through in vitro and in vivo studies, to be similar enough to the original comparator in term of quality, efficacy and safety. As biosimilars are less expensive than corresponding originators, a wider use of these drugs may substantially cut off the expenditure of biopharmaceuticals. Nevertheless, ongoing debate exists in scientific community: the intrinsic complex and large structure of biologic molecules besides the natural variability in the manufacturing processes might lead to a slightly different product respect to the original one, so that relevant implications for efficacy and safety concerns might arise, especially in the long-term period. Immunogenicity and extended indications of biosimilars represent further matter of discussion, too. Thus, before their approval and marketing, specific guidelines and steps imposed by national and/or international regulatory agencies should be followed along with the respect of scientific societies position in each specific contest
Risk of hepatitis B virus reactivation in rheumatoid arthritis patients undergoing biologic treatment : extending perspective from old to newer drugs
Hepatitis B virus (HBV) reactivation in rheumatoid arthritis (RA) patients undergoing biological therapy is not infrequent. This condition can occur in patients with chronic hepatitis B as well as in patients with resolved HBV infection. Current recommendations are mainly focused on prevention and management strategies of viral reactivation under tumor necrosis factor-\u3b1 inhibitors or chimeric monoclonal antibody rituximab. In recent years, growing data concerning HBV reactivation in RA patients treated with newer biological drugs like tocilizumab and abatacept have cumulated. In this review, epidemiology, pathogenesis and natural history of HBV infection have been revised first, mainly focusing on the role that specific therapeutic targets of current biotechnological drugs play in HBV pathobiology; finally we have summarized current evidences from scientific literature, including either observational studies and case reports as well, concerning HBV reactivation under different classes of biological drugs in RA patients. Taking all these evidences into account, some practical guidelines for screening, vaccination, prophylaxis and treatment of HBV reactivation have been proposed
The MEG detector for decay search
The MEG (Mu to Electron Gamma) experiment has been running at the Paul
Scherrer Institut (PSI), Switzerland since 2008 to search for the decay \meg\
by using one of the most intense continuous beams in the world. This
paper presents the MEG components: the positron spectrometer, including a thin
target, a superconducting magnet, a set of drift chambers for measuring the
muon decay vertex and the positron momentum, a timing counter for measuring the
positron time, and a liquid xenon detector for measuring the photon energy,
position and time. The trigger system, the read-out electronics and the data
acquisition system are also presented in detail. The paper is completed with a
description of the equipment and techniques developed for the calibration in
time and energy and the simulation of the whole apparatus.Comment: 59 pages, 90 figure
Market Power and Collusion on Interconnection Phone Market in Tunisia : What Lessons from International Experiences
We try in this paper to characterize the state of mobile phone market in Tunisia. Our study is based on a survey of foreign experience (Europe) in detecting collusive behavior and a comparison of the critical threshold of collusion between operators in developing countries like Tunisia. The market power is estimated based on the work of Parker Roller (1997) and the assumption of "Balanced Calling Pattern". We use then the model of Friedman (1971) to compare the critical threshold of collusion. We show that the "conduct parameter" measuring the intensity of competition is not null during the period 1993-2011. Results show also that collusion is easier on the Tunisian market that on the Algerian, Jordanian, or Moroccan one
Real-time feedback protocols for optimizing fault-tolerant two-qubit gate fidelities in a silicon spin system
Recently, several groups have demonstrated two-qubit gate fidelities in
semiconductor spin qubit systems above 99%. Achieving this regime of
fault-tolerant compatible high fidelities is nontrivial and requires exquisite
stability and precise control over the different qubit parameters over an
extended period of time. This can be done by efficiently calibrating qubit
control parameters against different sources of micro- and macroscopic noise.
Here, we present several single- and two-qubit parameter feedback protocols,
optimised for and implemented in state-of-the-art fast FPGA hardware.
Furthermore, we use wavelet-based analysis on the collected feedback data to
gain insight into the different sources of noise in the system. Scalable
feedback is an outstanding challenge and the presented implementation and
analysis gives insight into the benefits and drawbacks of qubit parameter
feedback, as feedback related overhead increases. This work demonstrates a
pathway towards robust qubit parameter feedback and systematic noise analysis,
crucial for mitigation strategies towards systematic high-fidelity qubit
operation compatible with quantum error correction protocols
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