scholarly journals On the existence of earthquake precursors

1999 ◽  
Vol 42 (5) ◽  
Author(s):  
F. Evison
Keyword(s):  
Empirical Research ◽  
Earthquake Prediction ◽  
Power Law ◽  
Earthquake Precursors ◽  
Time Varying ◽  
Formal Testing ◽  
High Degree ◽  
Experimental Stage

Earthquake prediction based on precursors can aim to provide fully quantified, time-varying, synoptic forecasts, which do not depart from physical and geological principles, and are amenable to formal testing. These features are in contrast to the traditional occultist or soothsayer style of prediction. The recently-advanced, pre-emptive hypothesis that earthquakes are intrinsically unpredictable, and precursors non-existent, is also amenable to testing: it is refuted by the well-known relations between mainshocks and aftershocks. These relations show that a set of aftershocks is to a high degree predictable from the mainshock, so that, as a matter of principle, the mainshock is a precursor to its aftershocks. This result is compatible with the power-law property of seismicity, on which the unpredictability hypothesis is based. Empirical research on most precursors is difficult because of the scarcity of data, and is still largely at the anecdotal stage. Additional difficulties at the experimental stage are exemplified by the failure of the Tokai and Parkfield experiments to advance the study of precursors as planned. A comparative abundance of data is available on seismicity anomalies, and research on this type of precursor is progressing towards the operational stage.

scholarly journals Continuous Magnitude Production of Loudness

2021 ◽  
Vol 12 ◽  
Author(s):  
Josef Schlittenlacher ◽  
Wolfgang Ellermeier
Keyword(s):  
Power Law ◽  
Line Length ◽  
Time Varying ◽  
Magnitude Production ◽  
Consistency Check ◽  
Regression Effects ◽  
Systematic Biases ◽  
Behavioural Experiments ◽  
The Given ◽  
Stevens’S Power Law

Continuous magnitude estimation and continuous cross-modality matching with line length can efficiently track the momentary loudness of time-varying sounds in behavioural experiments. These methods are known to be prone to systematic biases but may be checked for consistency using their counterpart, magnitude production. Thus, in Experiment 1, we performed such an evaluation for time-varying sounds. Twenty participants produced continuous cross-modality matches to assess the momentary loudness of fourteen songs by continuously adjusting the length of a line. In Experiment 2, the resulting temporal line length profile for each excerpt was played back like a video together with the given song and participants were asked to continuously adjust the volume to match the momentary line length. The recorded temporal line length profile, however, was manipulated for segments with durations between 7 to 12 s by eight factors between 0.5 and 2, corresponding to expected differences in adjusted level of −10, −6, −3, −1, 1, 3, 6, and 10 dB according to Stevens’s power law for loudness. The average adjustments 5 s after the onset of the change were −3.3, −2.4, −1.0, −0.2, 0.2, 1.4, 2.4, and 4.4 dB. Smaller adjustments than predicted by the power law are in line with magnitude-production results by Stevens and co-workers due to “regression effects.” Continuous cross-modality matches of line length turned out to be consistent with current loudness models, and by passing the consistency check with cross-modal productions, demonstrate that the method is suited to track the momentary loudness of time-varying sounds.

scholarly journals Doing Well By Doing Good In The Community: Evidence From Some South African Small Businesses

2015 ◽  
Vol 32 (1) ◽  
pp. 227
Author(s):  
D. Y. Dzansi
Keyword(s):  
South African ◽  
Empirical Research ◽  
Economic Performance ◽  
Small Businesses ◽  
Economic Benefits ◽  
Business Practice ◽  
Policy Makers ◽  
High Degree ◽  
African Setting ◽  
Do So

<p>Researchers and policy makers worldwide are convinced that only clear empirical evidence of the economic benefits of business social responsibility (BSR), rather than normative assertions, can motivate small businesses enough to accept and adopt it as an integral business practice. Unfortunately, empirical research so far has yielded mixed results, such that smaller businesses are right to be skeptical about adopting BSR. This paper reports the findings of empirical research on patterns of BSR engagement practices and growth in firms’ sales and gross profit among small and micro enterprises (SMMEs) in a South African setting. This is to determine how a small firm’s economic performance varies (if at all) with the degree of its BSR performance and the kind of BSR activity it engages in. The results suggest a high degree of BSR activity among firms with substantial portions of profit dedicated to BSR. However, contrary to expectations, very weak (minor) link was found between BSR performance and economic performance among the sample of small businesses on some but not all dimensions of BSR considered in the study. Nonetheless, it is recommended that managers and owners of small businesses be encouraged to adopt and practice BSR. Even if they do not do so for economic reasons, they would be right to do so to ‘atone’ for the widely acknowledged detrimental impacts of business on society. </p>

scholarly journals A Fast Algorithm to Find All High-Degree Vertices in Graphs with a Power-Law Degree Sequence

2014 ◽  
Vol 10 (1-2) ◽  
pp. 137-161 ◽  
Author(s):  
Colin Cooper ◽  
Tomasz Radzik ◽  
Yiannis Siantos
Keyword(s):  
Power Law ◽  
Fast Algorithm ◽  
Degree Sequence ◽  
Law Degree ◽  
High Degree

scholarly journals PHASE REARRANGEMENT IN LOCAL BALANCED HYDROGEOCHEMICAL SYSTEMS AS A OF FLUID EARTHQUAKE PRECURSORS MECHANISM OCCURRENCE

2019 ◽  
Vol 16 (33) ◽  
pp. 248-258
Author(s):  
A. U. ABDULLAEV
Keyword(s):  
Earthquake Prediction ◽  
Structural Relaxation ◽  
Earthquake Precursors ◽  
Strong Earthquakes ◽  
Major Earthquake ◽  
Time Period ◽  
Internal Phase ◽  
The World ◽  
Precursors Of Earthquakes ◽  
Hydrogeochemical System

Scientists all over the world are making tremendous efforts to solve the problem of earthquake prediction. Dozens of different phenomena and signs that could serve as precursors of earthquakes are found. But these effects were very unstable and had a mosaic character in the propagation of development and time. They appeared not always and not before every major earthquake. There are many cases where earthquakes occurred without the manifestation of any precursors. Such non-stationary phenomena do not allow formulating adequate strong earthquakes preparing models and their methods of predicting. Among well-studied and encouraging earthquake precursors, hydrogeodynamic and hydrogeochemical anomalies are considered to be the most promising, which has a sufficiently substantiated scientific background. In this class of precursors, the mechanism of their formation during the preparation of earthquakes remains debatable. There are several problems due to abnormal concentration sources and their transport during a little time period in the observation points. In the proposed work, it is proved that the main mechanism of the occurrence of exotic transient fluid anomalies is the interphase rearrangement in the local balanced hydrogeochemical system as a reaction to strong earthquakes factors preparing influence. The internal phase reorganization in the hydrogeochemical system is realized through structural relaxation as a result of the occurrence of rapid physicochemical reactions exchange.

scholarly journals Conceptualising state-market-family relationships in comparative research: a conceptual goodness view on defamilization

2020 ◽  
pp. 1-19
Author(s):  
HANNAH ZAGEL ◽  
HENNING LOHMANN
Keyword(s):  
Welfare State ◽  
Empirical Research ◽  
Family Relationships ◽  
Comparative Research ◽  
State Theory ◽  
Comparative Perspective ◽  
Large N ◽  
High Degree ◽  
Multidimensional Concept

Abstract This study evaluates the strengths and weaknesses of defamilization as a concept for analysing state-market-family relationships in comparative perspective. A paradox has emerged around defamilization in the last decade; its use in empirical large-N research has grown markedly despite mounting criticism in theoretical discussions. Applying criteria of conceptual goodness, we find that the popularity of the concept is based on its high degree of parsimony, theoretical utility and field utility, but that there are problems with the resonance, coherence and differentiation of the concept. We argue that defamilization is most coherent and has greatest utility if the concept’s roots in welfare state theory are fully acknowledged. In our view, this means that defamilization is best understood a) alongside the separate concept of familization, b) as a multidimensional concept in terms of economic and social dependencies in family relationships, and c) as a means of addressing both gender and intergenerational dependencies. Although suitable for operationalization in empirical research, the concept hence imposes high demands regarding the required data and possible analyses.

scholarly journals Grouting Reinforcement Technique in Wind Oxidation Zone by Power Law Superfine Cement Slurry Considering the Time-Varying Rheological Parameters

2019 ◽  
Vol 2019 ◽  
pp. 1-10
Author(s):  
Dengxing Zhu ◽  
Yu Guo ◽  
Wei Wang ◽  
Gangye Guo ◽  
Tieliang An
Keyword(s):  
Power Law ◽  
Coal Mine ◽  
Effective Diffusion ◽  
Oxidation Zone ◽  
Rheological Parameters ◽  
Time Varying ◽  
Cement Slurry ◽  
Permeability Characteristics ◽  
Grouting Pressure ◽  
Roof Strata

With the recovery of the wind oxidation zone in 13116 working face of Gubei Coal Mine as the engineering background, the occurrence condition of coal seam and the bedrock wind oxidation zone characteristics were analyzed. On this basis, the time-varying rheological parameters of superfine cement slurry and the permeability characteristic parameters of roof strata in wind oxidation zone were measured; then, a grout diffusion equation was established with the parameters obtained previously for the permeability characteristics of roof strata in the wind oxidation zone of Gubei Coal Mine. The grouting design was applied in actual engineering projects and its engineering effect has been proved to be satisfactory. The results indicate that superfine cement slurry whose water-cement ratio is 0.6 is a typical power-law slurry consistent with time-varying rheological parameters. It has better rheological properties during pumpable period, and its rheological parameters can be controlled by highly dispersive nano-SiO2 and polycarboxylate superplasticizer. For grouting in wind oxidized zone, comprehensive consideration must be given to effective permeability Ke, porosity  ∅ , and time-varying rheological parameters c0, k, and n. To realize effective diffusion of grouting in coal and rock mass, grouting pressure and diffusion time must be reasonably designed rather than excessively increased.

scholarly journals Variability and its limits in bilingual language production

2016 ◽  
Vol 19 (5) ◽  
pp. 855-856
Author(s):  
JUBIN ABUTALEBI ◽  
HARALD CLAHSEN
Keyword(s):  
Empirical Research ◽  
Language Production ◽  
Language Use ◽  
The Other ◽  
Speech Community ◽  
Language Performance ◽  
Activation Patterns ◽  
Speech Communities ◽  
High Degree ◽  
The Ideal

Experimental and other empirical research on language is faced with the fact that language performance exhibits a high degree of variability at all linguistic levels. Variability is found across languages, across speech communities within one language, across individuals within one speech community and even within the same individual. Bilingual language use adds a further source of variability to this already complicated picture. On the other hand, there are aspects of language and language use that are constrained, stable, or robust and that are less (or not at all) subject to variability, for example, possible options that are not chosen in any language or kinds of error that are never produced. Several familiar ways of dealing with the variability of language use and its limits have turned out to be unsatisfactory. One approach has been to simply abstract away from variability with constructs such as the ‘ideal speaker–hearer’ (who – to our knowledge – nobody has met so far). Another strategy is to average across individuals, which sometimes results in arbitrary mean scores or mean activation patterns that are hard to replicate for individuals, even for those who took part in a given study. A third solution when confronted with variability in language use is to take it at face value, positing that every language, every speech community, and even every individual is different, an approach that essentially gives up on discovering any kind of generalizations. While none of these strategies appears to us to be particularly fruitful, the problem of how to deal with variability in language performance and its limits remains.

Identifying Musically Gifted Children

1982 ◽  
Vol 5 (1) ◽  
pp. 56-66 ◽  
Author(s):  
Albert Dorhout
Keyword(s):  
Selection Procedure ◽  
Gifted Children ◽  
Music Educator ◽  
Systematic Assessment ◽  
Formal Testing ◽  
Physical Maturation ◽  
Performance Ability ◽  
High Degree ◽  
Selection Of

The procedure of judging overt performance ability is a widely accepted one for the identification of musically gifted children. There may be those, however, who possess both a high degree of sensitivity to sound and mature insights into the meaning of that sound, yet lack the physical maturation essential to demonstrate these traits. A delay in the development of psychomotor coordination can mask a child's true musical talents. Those responsible for identifying musically gifted children should adopt a multifaceted procedure utilizing information from the child, his/her peers, parents, teachers and impartial judges. A systematic assessment of the child's aptitude, achievement and attitude levels should be employed through formal testing. The strengths and weaknesses of several standardized instruments are discussed to assist the music educator in the selection of the appropriate instruments for the evaluation of the child's potential. A matrix is then suggested to expedite the selection procedure.

scholarly journals Correlation-based characterisation of time-varying dynamical complexity in the Earth's magnetosphere

2013 ◽  
Vol 20 (6) ◽  
pp. 965-975 ◽  
Author(s):  
R. V. Donner ◽  
G. Balasis
Keyword(s):  
Dynamical Behaviour ◽  
Magnetic Storms ◽  
Time Varying ◽  
Temporal Complexity ◽  
Multi Scale ◽  
Dynamical Complexity ◽  
Geophysical Time Series ◽  
Recorded Data ◽  
Different Characteristics ◽  
High Degree

Abstract. The dynamical behaviour of the magnetosphere is known to be a sensitive indicator for the response of the system to solar wind coupling. Since the solar activity commonly displays very interesting non-stationary and multi-scale dynamics, the magnetospheric response also exhibits a high degree of dynamical complexity associated with fundamentally different characteristics during periods of quiescence and magnetic storms. The resulting temporal complexity profile has been explored using several approaches from applied statistics, dynamical systems theory and statistical mechanics. Here, we propose an alternative way of looking at time-varying dynamical complexity of nonlinear geophysical time series utilising subtle but significant changes in the linear autocorrelation structure of the recorded data. Our approach is demonstrated to sensitively trace the dynamic signatures associated with intense magnetic storms, and to display reasonable skills in distinguishing between quiescence and storm periods. The potentials and methodological limitations of this new viewpoint are discussed in some detail.

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