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Magmatic and metamorphic zircons have been dated from ductilely deformed gabbroic dykes defining a dyke swarm and signifying crustal extension in the northern part of the Hengshan Complex of the North China Craton, These dykes now occur as boudins and deformed sheets within migmatitic tonalitic, trondhjemitic, granodioritic and granitic gneisses and are conspicuous due to relics of high-pressure granulite or even former eclogite facies garnet + pyroxene-bearing assemblages. SHRIMP ages for magmatic zircons from two dykes reflect the time of dyke emplacement at similar to 1915 Ma, whereas metamorphic zircons dated by both SHRIMP and evaporation techniques are consistently in the range 1848-1888 Ma. The Youngest granitoid gneiss yet dated in the Hengshan has an emplacement age of 18 2 17 Ma. These results complement recent geochronological studies from the neighbouring Wutai and Fuping Complexes, to the SE of the Hengshan, showing that a crustal extension event Occurred in the late Palaeoproterozoic. This preceded a major high-pressure collision- type metamorphic event in the central part of the North China Craton that occurred in the Palaeoproterozoic and not in the late Archaean as previously thought. Our data support recent suggestions that the North China Craton experienced a major, craton-wide orogenic event in the late Palaeoproterozoic after which it became cratonized and acted as a stable block.
For the first time, site-selective distortion has been investigated for two different structural units in the ternary compound alpha-GaPO4 under the influence of a permanent external electric field. Based on 54 measured reflection intensities, the electric-field-induced distortion of PO4 and GaO4 tetrahedra in alpha-GaPO4 crystals is evaluated using a model of pseudoatomic displacements introduced recently [Gorfman, Tsirelson & Pietsch (2005). Acta Cryst. A61, 387- 396]. A stronger variation of the P-O bond lengths in the PO4 tetrahedron was found compared to the bonds in the GaO4 tetrahedron. The different distortions of the tetrahedra owing to the electric field were analysed in terms of the valence charge density of alpha-GaPO4 and its topological characteristics. The larger charge of the P pseudoatom compared to the Ga atom was recognized as the main reason for the higher sensitivity of the PO4 tetrahedron to a permanent external electric field
We asked 149 high-school students who were pretested for their working memory capacity (WMC) to read spatial descriptions relating to five objects and to evaluate conclusions asserting an unmentioned relationship between two of the objects. Unambiguous descriptions were compatible with a single spatial arrangement, whereas ambiguous descriptions permitted two arrangements; a subset of the ambiguous descriptions still determined the relation asserted in the conclusion, whereas another subset did not. Two groups of participants received different instructions: The deduction group should accept conclusions only if they followed with logical necessity from the description, whereas the comprehension group should accept a conclusion if it agreed with their representation of the arrangement. Self-paced reading times increased on sentences that introduced an ambiguity, replicating previous findings in deductive reasoning experiments. This effect was also found in the comprehension group, casting doubt on the interpretation that people consider multiple possible arrangements online. Responses to conclusions could be modelled by a multinomial processing model with four parameters: the probability of constructing a correct mental model, the probability of detecting an ambiguity, and two guessing parameters. Participants with high and with low WMC differed mainly in the probability of successfully constructing a mental model
Recent research has shown that the early lexical representations children establish in their second year of life already seem to be phonologically detailed enough to allow differentiation from very similar forms. In contrast to these findings children with specific language impairment show problems in discriminating phonologically similar word forms up to school age. In our study we investigated the question whether there would be differences in the processing of phonological details in normally developing and in children with low language performance in the second year of life. This was done by a retrospective study in which in the processing of phonological details was tested by a preferential looking experiment when the children were 19 months old. At the age of 30 months children were tested with a standardized German test of language comprehension and production (SETK2). The preferential looking data at 19 months revealed an opposite reaction pattern for the two groups: while the children scoring normally in the SETK2 increase their fixations of a pictured object only when it was named with the correct word, children with later low language performance did so only when presented with a phonologically slightly deviant mispronunciation. We suggest that this pattern does not point to a specific deficit in processing phonological information in these children but might be related to an instability of early phonological representations, and/or a generalized problem of information processing as compared to typically developing children.
Previous research has shown that in a three-term spatial reasoning task, the second premise of a German premise pair is especially easy to comprehend if (1) the prepositional object rather than the grammatical subject denotes the given entity, and if (2) the term denoting the given entity precedes the term denoting the new entity. Accordingly, the second premise is easiest to comprehend with noncanonical word order-that is, with the prepositional object in preverbal position denoting the given entity (e.g., To the right of the given object is the new subject). This finding is explained in terms of contextual licensing of noncanonical word order. Here, we discuss and tested two alternative accounts of contextual licensing, given-new and partially ordered set relations (Poset). The given-new account claims that noncanonical word order is licensed by the term denoting the given entity preceding the term denoting the new entity. On the Poset account, noncanonical word order is licensed if the preverbal constituent introduces a new entity that stands in a transitive, irreflexive, and asymmetric relation to a given entity. Comprehension times for second premises with spatial adverbs in four different word orders support both accounts of contextual licensing; Poset licensing was stronger than given-new licensing.
We propose a new autonomous dynamical system of dimension N=4 that demonstrates the regime of stable two- frequency motions and period-doubling bifurcations of a two-dimensional torus. It is shown that the period-doubling bifurcation of the two-dimensional torus is not followed by the resonance phenomenon, and the two-dimensional ergodic torus undergoes a period-doubling bifurcation. The interaction of two generators is also analyzed. The phenomenon of external and mutual synchronization of two-frequency oscillations is observed, for which winding number locking on a two- dimensional torus takes place
A study with 114 young adults investigated the correlations of intelligence factors and working-memory capacity with reaction time (RT) tasks. Within two sets of four-choice RT tasks, stimulus-response compatibility was varied over three levels: compatible, incompatible, and arbitrary mappings. Two satisfactory measurement models for the RTs could be established: A general factor model without constraints on the loadings and a nested model with two correlated factors, distinguishing compatible from arbitrary mappings, with constraints on the loadings. Structural models additionally including factors for working memory and intelligence showed that the nested model with correlated factors is superior in fit. Working-memory capacity and fluid intelligence were correlated strongly with the nested factor for the RT tasks with arbitrary mappings, and less with the general RT factor. The results support the hypothesis that working memory is needed to maintain arbitrary bindings between stimulus representations and response representations, and this could explain the correlation of working-memory capacity with speed in choice RT tasks
What’s in an irish name?
(2006)
Content: 1. Introduction: The Irish Patronymic System Prior to 1600 2. Anglicisation Pressure 3. Anglicisation: 1600-1900 3.1. Phonetic Approximation 3.2. Simplification 3.3. Translation 3.4. Mistranslation 3.5. Equivalence with Existing English Surname 3.6. Multiplicity of Anglicised Forms 3.7. Anglicisation of Prefixes 4. The Call to De-Anglicise 5. Current Personal Naming Patterns in Ireland 5.1. Current Modern Irish 6. Traditional Naming: “X (Son/Daughter) of Y (Son/Daughter) of Z” 7. Nicknames 8. Conclusion
What can we learn from climate data? : Methods for fluctuation, time/scale and phase analysis
(2006)
Since Galileo Galilei invented the first thermometer, researchers have tried to understand the complex dynamics of ocean and atmosphere by means of scientific methods. They observe nature and formulate theories about the climate system. Since some decades powerful computers are capable to simulate the past and future evolution of climate. Time series analysis tries to link the observed data to the computer models: Using statistical methods, one estimates characteristic properties of the underlying climatological processes that in turn can enter the models. The quality of an estimation is evaluated by means of error bars and significance testing. On the one hand, such a test should be capable to detect interesting features, i.e. be sensitive. On the other hand, it should be robust and sort out false positive results, i.e. be specific. This thesis mainly aims to contribute to methodological questions of time series analysis with a focus on sensitivity and specificity and to apply the investigated methods to recent climatological problems. First, the inference of long-range correlations by means of Detrended Fluctuation Analysis (DFA) is studied. It is argued that power-law scaling of the fluctuation function and thus long-memory may not be assumed a priori but have to be established. This requires to investigate the local slopes of the fluctuation function. The variability characteristic for stochastic processes is accounted for by calculating empirical confidence regions. The comparison of a long-memory with a short-memory model shows that the inference of long-range correlations from a finite amount of data by means of DFA is not specific. When aiming to infer short memory by means of DFA, a local slope larger than $\alpha=0.5$ for large scales does not necessarily imply long-memory. Also, a finite scaling of the autocorrelation function is shifted to larger scales in the fluctuation function. It turns out that long-range correlations cannot be concluded unambiguously from the DFA results for the Prague temperature data set. In the second part of the thesis, an equivalence class of nonstationary Gaussian stochastic processes is defined in the wavelet domain. These processes are characterized by means of wavelet multipliers and exhibit well defined time dependent spectral properties; they allow one to generate realizations of any nonstationary Gaussian process. The dependency of the realizations on the wavelets used for the generation is studied, bias and variance of the wavelet sample spectrum are calculated. To overcome the difficulties of multiple testing, an areawise significance test is developed and compared to the conventional pointwise test in terms of sensitivity and specificity. Applications to Climatological and Hydrological questions are presented. The thesis at hand mainly aims to contribute to methodological questions of time series analysis and to apply the investigated methods to recent climatological problems. In the last part, the coupling between El Nino/Southern Oscillation (ENSO) and the Indian Monsoon on inter-annual time scales is studied by means of Hilbert transformation and a curvature defined phase. This method allows one to investigate the relation of two oscillating systems with respect to their phases, independently of their amplitudes. The performance of the technique is evaluated using a toy model. From the data, distinct epochs are identified, especially two intervals of phase coherence, 1886-1908 and 1964-1980, confirming earlier findings from a new point of view. A significance test of high specificity corroborates these results. Also so far unknown periods of coupling invisible to linear methods are detected. These findings suggest that the decreasing correlation during the last decades might be partly inherent to the ENSO/Monsoon system. Finally, a possible interpretation of how volcanic radiative forcing could cause the coupling is outlined.
We present the results of phase-referenced VLBA+Effelsberg observations at five frequencies of the double-image gravitational lens WAS B0218+357, made to establish the precise registration of the A and B lensed image positions. The motivation behind these observations is to investigate the anomalous variation of the image flux-density ratio (A[B) with frequency - this ratio changes by almost a factor of two over a frequency range from 1.65 GHz to 15.35 GHz. We investigate whether frequency dependent image positions, combined with a magnification gradient across the image field, could give rise to the anomaly. Our observations confirm the variation of image flux-density ratio with frequency. The results from Our phase-reference astrometry, taken together with the lens mass model of Wucknitz et al. (2004, MNRAS, 349, 14), show that shifts of the image peaks and centroids are too small to account for the observed frequency- dependent ratio
Dynamics in urban environments encompasses complex processes and phenomena such as related to movement (e.g.,traffic, people) and development (e.g., construction, settlement). This paper presents novel methods for creating human-centric illustrative maps for visualizing the movement dynamics in virtual 3D environments. The methods allow a viewer to gain rapid insight into traffic density and flow. The illustrative maps represent vehicle behavior as light threads. Light threads are a familiar visual metaphor caused by moving light sources producing streaks in a long-exposure photograph. A vehicle’s front and rear lights produce light threads that convey its direction of motion as well as its velocity and acceleration. The accumulation of light threads allows a viewer to quickly perceive traffic flow and density. The light-thread technique is a key element to effective visualization systems for analytic reasoning, exploration, and monitoring of geospatial processes.
We study the overdamped version of two coupled anharmonic oscillators under the influence of both low- and high-frequency forces respectively and a Gaussian noise term added to one of the two state variables of the system. The dynamics of the system is first studied in the presence of both forces separately without noise. In the presence of only one of the forces, no resonance behaviour is observed, however, hysteresis happens there. Then the influence of the high-frequency force in the presence of a low-frequency, i.e. biharmonic forcing, is studied. Vibrational resonance is found to occur when the amplitude of the high-frequency force is varied. The resonance curve resembles a stochastic resonance-like curve. It is maximum at the value of g at which the orbit lies in one well during one half of the drive cycle of the low-frequency force and in the other for the remaining half cycle. Vibrational resonance is characterized using the response amplitude and mean residence time. We show the occurrence of stochastic resonance behaviour in the overdamped system by replacing the high-frequency force by Gaussian noise. Similarities and differences between both types of resonance are presented. (c) 2006 Elsevier B.V. All rights reserved.
Forum: EU-Diplomatie im Jahre 2020