Power Laws in Ad Hoc Conflictual Discussions on Twitter

2018 ◽  
pp. 67-82
Author(s):  
Svetlana S. Bodrunova ◽  
Ivan S. Blekanov
Keyword(s):  
Ad Hoc ◽  
Power Laws

The Equations Archie Forgot: Anisotropy of the Rocks

2010 ◽  
Vol 13 (05) ◽  
pp. 823-836 ◽  
Author(s):  
Carlos F. Haro
Keyword(s):  
Ad Hoc ◽  
Water Saturation ◽  
Power Laws ◽  
Fluid Distribution ◽  
Data Sets ◽  
Solution Flow ◽  
Original Analysis ◽  
Particular Solution ◽  
Saturation Exponent ◽  
Complex Formations

Summary Archie's empirical equation is used extensively to estimate hydrocarbons in place. This power-laws combination has stood the test of time with few changes. However, it is still poorly understood and considered an ad hoc relation. Our original analysis will prove these laws rigorously, show how they must be amended, and introduce additional accompanying equations. This comprehensive model, which represents the electrical flow through the intricate conductive paths of the rock, is confirmed with Archie's and Hamada's core data sets. It corrects for Archie's inaccuracies. A thorough appreciation of the pore-scale physics behind the modified version of Archie's equation is presented. The principles can be applied in clean and complex formations (shaly sands, thin beds, and vuggy or fractured carbonates) to obtain enhanced values of water saturation. The theory sheds light on the role and quantification of anisotropy. Solving for the elaborate pore geometry, we use the Laplace differential equation (not Ohm's law), appropriate in the analysis of electrostatic fields in charge-free regions. Rock morphology dictates its boundary conditions (Jin 2007; Ghous 2005), characterized as corner angles. The corresponding particular solution (flow around a corner) and modeling tactic delineate the streamlines throughout the pores. The angles establish strong mathematical links among the exponents of Archie's equation, the geometry of the rock frame, and the spatial fluid distribution. This quantitative method is lacking in previous saturation models. The solution constitutes the basis to solve more-complicated rock layouts. It enables the calculation of equivalent resistivities (normalized resistances) to take advantage of well-established electrical relationships. The extra equations compute the variable exponents and coefficients of Archie's equation at every depth. They obtain the saturation exponent in clean rocks as a function of water saturation, crucial to the quality control of core electrical data and to the quantification of reservoirs under changing saturation (waterflooding). Therefore, improved calculations of original and remaining hydrocarbons are achieved.

scholarly journals Power Law Duality in Classical and Quantum Mechanics

Symmetry ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 409
Author(s):  
Akira Inomata ◽  
Georg Junker
Keyword(s):  
Quantum Mechanics ◽  
Green Function ◽  
Power Law ◽  
Ad Hoc ◽  
Fractional Power ◽  
Power Laws ◽  
Energy Coupling ◽  
Arbitrary Power ◽  
Dual Symmetry ◽  
The Green Function

The Newton–Hooke duality and its generalization to arbitrary power laws in classical, semiclassical and quantum mechanics are discussed. We pursue a view that the power-law duality is a symmetry of the action under a set of duality operations. The power dual symmetry is defined by invariance and reciprocity of the action in the form of Hamilton’s characteristic function. We find that the power-law duality is basically a classical notion and breaks down at the level of angular quantization. We propose an ad hoc procedure to preserve the dual symmetry in quantum mechanics. The energy-coupling exchange maps required as part of the duality operations that take one system to another lead to an energy formula that relates the new energy to the old energy. The transformation property of the Green function satisfying the radial Schrödinger equation yields a formula that relates the new Green function to the old one. The energy spectrum of the linear motion in a fractional power potential is semiclassically evaluated. We find a way to show the Coulomb–Hooke duality in the supersymmetric semiclassical action. We also study the confinement potential problem with the help of the dual structure of a two-term power potential.

scholarly journals How rare are power-law networks really?

2020 ◽  
Vol 476 (2241) ◽  
pp. 20190742
Author(s):  
I. Artico ◽  
I. Smolyarenko ◽  
V. Vinciotti ◽  
E. C. Wit
Keyword(s):  
Power Law ◽  
Ad Hoc ◽  
Null Distribution ◽  
Power Laws ◽  
Testing Procedure ◽  
Statistical Testing ◽  
Power Law Distribution ◽  
Scale Free ◽  
Common Structure ◽  
Power Of The Test

The putative scale-free nature of real-world networks has generated a lot of interest in the past 20 years: if networks from many different fields share a common structure, then perhaps this suggests some underlying ‘network law’. Testing the degree distribution of networks for power-law tails has been a topic of considerable discussion. Ad hoc statistical methodology has been used both to discredit power-laws as well as to support them. This paper proposes a statistical testing procedure that considers the complex issues in testing degree distributions in networks that result from observing a finite network, having dependent degree sequences and suffering from insufficient power. We focus on testing whether the tail of the empirical degrees behaves like the tail of a de Solla Price model, a two-parameter power-law distribution. We modify the well-known Kolmogorov–Smirnov test to achieve even sensitivity along the tail, considering the dependence between the empirical degrees under the null distribution, while guaranteeing sufficient power of the test. We apply the method to many empirical degree distributions. Our results show that power-law network degree distributions are not rare, classifying almost 65% of the tested networks as having a power-law tail with at least 80% power.

Committees: Standing and Ad Hoc

1965 ◽  
Vol 1 (3) ◽  
pp. 68-68
Keyword(s):  
Ad Hoc

Die COVID-19-Pandemie im akutstationären Setting aus Sicht von Führungspersonen und Hygienefachkräften in der Pflege

Pflege ◽  
2020 ◽  
Vol 33 (5) ◽  
pp. 289-298
Author(s):  
Katharina Silies ◽  
Angelika Schley ◽  
Janna Sill ◽  
Steffen Fleischer ◽  
Martin Müller ◽  
...  
Keyword(s):  
Ad Hoc ◽  
Qualitative Studie ◽  
Skill Mix ◽  
Task Forces

Zusammenfassung. Hintergrund: Die COVID-19-Pandemie ist eine Ausnahmesituation ohne Präzedenz und erforderte zahlreiche Ad-hoc-Anpassungen in den Strukturen und Prozessen der akutstationären Versorgung. Ziel: Ziel war es zu untersuchen, wie aus Sicht von Führungspersonen und Hygienefachkräften in der Pflege die stationäre Akutversorgung durch die Pandemiesituation beeinflusst wurde und welche Implikationen sich daraus für die Zukunft ergeben. Methoden: Qualitative Studie bestehend aus semistrukturierten Interviews mit fünf Verantwortlichen des leitenden Pflegemanagements und drei Hygienefachkräften in vier Krankenhäusern in Deutschland. Die Interviews wurden mittels qualitativer Inhaltsanalyse ausgewertet. Ergebnisse: Die Befragten beschrieben den auf die prioritäre Versorgung von COVID-19-Fällen hin umstrukturierten Klinikalltag. Herausforderungen waren Unsicherheit und Angst bei den Mitarbeiter_innen, relative Ressourcenknappheit von Material und Personal und die schnelle Umsetzung neuer Anforderungen an die Versorgungleistung. Dem wurde durch gezielte Kommunikation und Information, massive Anstrengungen zur Sicherung der Ressourcen und koordinierte Steuerung aller Prozesse durch bereichsübergreifende, interprofessionelle Task Forces begegnet. Schlussfolgerungen: Die in der COVID-19-Pandemie vorgenommenen Anpassungen zeigen Entwicklungspotenziale für die zukünftige Routineversorgung auf, z. B. könnten neue Arbeits- und Skill Mix-Modelle aufgegriffen werden. Für die Konkretisierung praktischer Implikationen sind vertiefende Analysen der Daten mit zeitlichem Abstand erforderlich.

Tests und Tools

2006 ◽  
Vol 5 (2) ◽  
pp. 68-71 ◽  
Author(s):  
Simone Kauffeld
Keyword(s):  
Ad Hoc ◽  
Non Profit

Zusammenfassung. Der FEO, der in Kooperation mit betrieblichen Praktikern entwickelt wurde, dient der Erfassung des Organisationsklimas. Er umfasst 82 Items und bildet 12 Skalen ab. Eine Stärke des FEO im Gegensatz zu ad hoc entwickelten Befragungsinstrumenten sind die Vergleichsdaten, die für Profit- und Non-Profit-Organisationen bereit gestellt werden. Kritisch diskutiert wird die theoretische Verortung, die Anwenderfreundlichkeit sowie der Nutzen der individuellen Auswertung. Die konsensuale, konvergente, diskriminante und kriterienbezogene Validierung steht aus.

Test Use in Spain, Portugal and Latin American Countries

1999 ◽  
Vol 15 (2) ◽  
pp. 151-157 ◽  
Author(s):  
José Muñiz ◽  
Gerardo Prieto ◽  
Leandro Almeida ◽  
Dave Bartram
Keyword(s):  
Latin American ◽  
Ad Hoc ◽  
Task Force ◽  
Test Construction ◽  
European Federation ◽  
Psychometric Characteristics ◽  
Testing Practices ◽  
Professional Psychologists ◽  
Test Use ◽  
Latin American Countries

Summary: The two main sources of errors in educational and psychological evaluation are the lack of adequate technical and psychometric characteristics of the tests, and especially the failure to properly implement the testing process. The main goal of the present research is to study the situation of test construction and test use in the Spanish-speaking (Spain and Latin American countries) and Portuguese-speaking (Portugal and Brazil) countries. The data were collected using a questionnaire constructed by the European Federation of Professional Psychologists Association (EFPPA) Task Force on Tests and Testing, under the direction of D. Bartram . In addition to the questionnaire, other ad hoc data were also gathered. Four main areas of psychological testing were investigated: Educational, Clinical, Forensic and Work. Key persons were identified in each country in order to provide reliable information. The main results are presented, and some measures that could be taken in order to improve the current testing practices in the countries surveyed are discussed. As most of the tests used in these countries were originally developed in other cultures, a problem that appears to be especially relevant is the translation and adaptation of tests.

Ad Hoc Reviewers 2015

2015 ◽  
Vol 31 (4) ◽  
pp. 313-314
Keyword(s):  
Ad Hoc
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