160 research outputs found

    Exploring the hidden potential of sugar beet industry brownfields (case study of the Czech Republic).

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    The paper focuses on spatial analyses of sugar beet industry brownfields in the Czech Republic. In the first part of the paper history of sugar beet industry on the area of the Czech Republic is briefly presented, then links between location of these sites and its transport potential are discussed. Benefits of brownfields regeneration for regional development are also evaluated. In the empirical part of the paper 49 brownfield sites within the Czech Republic, where the sugar beet industry was abandoned during the transition period after 1989, are evaluated and classified based on field research and aerial picture analyses. Three examples of reuse of former sugar beet factories are finally presented. It was found that development potential of studied sites is highly depended on their geographical location and some inspiration might be derived from presented examples. More targeted supportive policy in the Czech Republic to support regeneration of brownfields is needed. In the concluding part of the paper further development possibilities of sugar beet industry brownfields and their railway connection are considered

    Observation of secondary instability of 2/1 magnetic island in compass high density limit plasmas

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    Density limit disruptions (DLDs) have been observed in tokamak plasmas when high density regimes are explored. The DLDs are harmless in small size tokamaks like COMPASS,larger tokamaks like JET try to avoid them and they are extremely undesirable in ITER sizetokamaks due to the severe structural damages they can cause. It is very important to understand the dynamics of the DLDs so that better strategies to ameliorate or avoid them can bedeveloped. In this work, following detection in JET [1] of a secondary instability (SI) to thewell-known m/n = 2/1 MHD mode (where m and n are the poloidal and toroidal mode numbers, respectively) in the precursor of DLD, we analyse the evolution of the 2/1 magnetic islandin COMPASS DLD to look for the presence of this SI just close to the onset of energy quenchphase of the disruption. The presence of this SI to the magnetic island was associated with theoccurrence of minor disruptions preceding the major disruption and with the major disruptionitself in [1]. The coherence observed between the perturbations caused by the SI in the magneticpoloidal flux and in the electron temperature was very high (above 0.9), allowing to determinethat the SI perturbations came from the same position as the magnetic island. In the work presented here, only the perturbations in the magnetic poloidal flux are analysed since at the time ofthe experiments in COMPASS, no diagnostics was operational for measuring the time evolutionof the electron temperature with high time rate.Nonlinear MHD numerical simulations have also shown that island deformation during itsrapid growth can lead to the secondary magnetic island formation [2]. A recent review [3] ofthe theory of current sheet formation that leads to magnetic reconnection discusses the role ofplasmoids during magnetic island evolution. Since the validity ranges of the mentioned theoretical works are not directly comparable to the experimental conditions, one cannot claimwith certainty that the SI observed in JET [1] and in COMPASS disruptions (reported here)are the same as observed in those numerical works [2, 3]. However, there are some qualitative43rd EPS Conference on Plasma Physics P5.003similarities between them.The main COMPASS [4] diagnostics used for the analysis in the present work, are the threetoroidally separated arrays (A at 32.5â—¦, B at 212.5â—¦and C at 257.5â—¦from the vessel axis) ofMirnov coils (MCs), each with 24 MCs located poloidally. The MC arrays A and C, toroidallyseparated by 135â—¦, measure the change in poloidal magnetic flux, dBp/dt. The MC array B,toroidally separated by 180â—¦to the array A, measures the poloidal magnetic field, Bp. Thesemagnetic sensors have good responsivity to high frequency (up to 1 MHz)

    Projective Ring Line of a Specific Qudit

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    A very particular connection between the commutation relations of the elements of the generalized Pauli group of a dd-dimensional qudit, dd being a product of distinct primes, and the structure of the projective line over the (modular) ring \bZ_{d} is established, where the integer exponents of the generating shift (XX) and clock (ZZ) operators are associated with submodules of \bZ^{2}_{d}. Under this correspondence, the set of operators commuting with a given one -- a perp-set -- represents a \bZ_{d}-submodule of \bZ^{2}_{d}. A crucial novel feature here is that the operators are also represented by {\it non}-admissible pairs of \bZ^{2}_{d}. This additional degree of freedom makes it possible to view any perp-set as a {\it set-theoretic} union of the corresponding points of the associated projective line

    Kochen-Specker Theorem for Finite Precision Spin One Measurements

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    Unsharp spin 1 observables arise from the fact that a residual uncertainty about the actual orientation of the measurement device remains. If the uncertainty is below a certain level, and if the distribution of measurement errors is covariant under rotations, a Kochen-Specker theorem for the unsharp spin observables follows: There are finite sets of directions such that not all the unsharp spin observables in these directions can consistently be assigned approximate truth-values in a non-contextual way.Comment: 4 page

    Existential Contextuality and the Models of Meyer, Kent and Clifton

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    It is shown that the models recently proposed by Meyer, Kent and Clifton (MKC) exhibit a novel kind of contextuality, which we term existential contextuality. In this phenomenon it is not simply the pre-existing value but the actual existence of an observable which is context dependent. This result confirms the point made elsewhere, that the MKC models do not, as the authors claim, ``nullify'' the Kochen-Specker theorem. It may also be of some independent interest.Comment: Revtex, 7 pages, 1 figure. Replaced with published versio

    Bases for qudits from a nonstandard approach to SU(2)

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    Bases of finite-dimensional Hilbert spaces (in dimension d) of relevance for quantum information and quantum computation are constructed from angular momentum theory and su(2) Lie algebraic methods. We report on a formula for deriving in one step the (1+p)p qupits (i.e., qudits with d = p a prime integer) of a complete set of 1+p mutually unbiased bases in C^p. Repeated application of the formula can be used for generating mutually unbiased bases in C^d with d = p^e (e > or = 2) a power of a prime integer. A connection between mutually unbiased bases and the unitary group SU(d) is briefly discussed in the case d = p^e.Comment: From a talk presented at the 13th International Conference on Symmetry Methods in Physics (Dubna, Russia, 6-9 July 2009) organized in memory of Prof. Yurii Fedorovich Smirnov by the Bogoliubov Laboratory of Theoretical Physics of the JINR and the ICAS at Yerevan State University

    Changes in salivary estradiol predict changes in women’s preferences for vocal masculinity

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    Although many studies have reported that women’s preferences for masculine physical characteristics in men change systematically during the menstrual cycle, the hormonal mechanisms underpinning these changes are currently poorly understood. Previous studies investigating the relationships between measured hormone levels and women’s masculinity preferences tested only judgments of men’s facial attractiveness. Results of these studies suggested that preferences for masculine characteristics in men’s faces were related to either women’s estradiol or testosterone levels. To investigate the hormonal correlates of within-woman variation in masculinity preferences further, here we measured 62 women’s salivary estradiol, progesterone, and testosterone levels and their preferences for masculine characteristics in men’s voices in five weekly test sessions. Multilevel modeling of these data showed that changes in salivary estradiol were the best predictor of changes in women’s preferences for vocal masculinity. These results complement other recent research implicating estradiol in women’s mate preferences, attention to courtship signals, sexual motivation, and sexual strategies, and are the first to link women’s voice preferences directly to measured hormone levels
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