Fast Deterministic Selection

The Median of Medians (also known as BFPRT) algorithm, although a landmark theoretical achievement, is seldom used in practice because it and its variants are slower than simple approaches based on sampling. The main contribution of this paper is a fast linear-time deterministic selection algorithm QuickselectAdaptive based on a refined definition of MedianOfMedians. The algorithm's performance brings deterministic selection---along with its desirable properties of reproducible runs, predictable run times, and immunity to pathological inputs---in the range of practicality. We demonstrate results on independent and identically distributed random inputs and on normally-distributed inputs. Measurements show that QuickselectAdaptive is faster than state-of-the-art baselines.Comment: Pre-publication draf

Images of Music and Musicians as Indicators of Status, Wealth and Political Power on Roman Funerary Monuments

Untersuchungen bildlicher Darstellungen von Musikinstrumenten sowie Musikantinnen und Musikanten haben ergeben, dass sie in Grabkontexten benutzt wurden, um auf den Wohlstand sowie den politischen oder sozialen Status der verstorbenen Person oder ihrer Familie hinzuweisen. Dieser Beitrag gibt einen Überblick über die Ergebnisse der Analyse, basierend auf Beispielen aus republikanischen, imperialen und spätantiken Kontexten. Ziel des Beitrags ist, Veränderungen zu untersuchen, die sich sowohl auf die Bedeutung der für die Grabmäler gewählten Themen als auch auf die Rolle der Musikantinnen und Musikanten im Alltag auswirkten

NUMERICAL SIMULATION OF ICE ACCRETION ON AIRFOIL

This work consists in the simulation of the ice accretion in the leading edge of aerodynamic profiles and our proposed model encompasses: geometry generation, calculation of the potential flow around the body, boundary layer thickness computation, water droplet trajectory computation, heat and mass balances and the consequent modification of the geometry by the ice growth. The flow calculation is realized with panel methods, using only segments defined over the body contour. The viscous effects are considered using the Karman-Pohlhausen method for the laminar boundary layer. The local heat transfer coefficient is obtained by applying the Smith-Spalding method for the thermal boundary layer. The ice accretion limits and the collection efficiency are determined by computing water droplet trajectories impinging the surface. The heat transfer process is analyzed with an energy and a mass balance in each segment defining the body. Finally, the geometry is modified by the addition of the computed ice thickness to the respective panel. The process by repeating all the steps. The model validation is done using a selection of problems with experimental solution, CIRA (the CESAR project). Hereinafter, results are obtained for different aerodynamic profiles, angles of attack and meteorological parameter

Theoretical and numerical method in aeroacoustics

The paper deals with the mathematical and numerical modeling of the aerodynamic noisegenerated by the fluid flow interaction with the solid structure of a rotor blade.Our analysis use Lighthill’s acoustic analogy. Lighthill idea was to express the fundamental equationsof motion into a wave equation for acoustic fluctuation with a source term on the right-hand side. Theobtained wave equation is solved numerically by the spatial discretization. The method is applied inthe case of monopole source placed in different points of blade surfaces to find this effect of noisepropagation

Matter-wave solitons supported by dissipation

We show how novel types of long-lived self-localized matter waves can be constructed with Bose-Einstein condensates. The ingredients leading to such structures are a spatial phase generating a flux of atoms towards the condensate center and the dissipative mechanism provided by the inelastic three-body collisions in atomic Bose-Einstein condensates. The outcome is an striking example of nonlinear structure supported by dissipation

Einstein's Photon Concept Quantified by the Bohr Model of the Photon

The photon is modeled as a monochromatic solution of Maxwell's equations confined as a soliton wave by the principle of causality of special relativity. The soliton travels rectilinearly at the speed of light. The solution can represent any of the known polarization (spin) states of the photon. For circularly polarized states the soliton's envelope is a circular ellipsoid whose length is the observed wavelength ($\lambda$), and whose diameter is $\lambda/\pi$; this envelope contains the electromagnetic energy of the wave ($h\nu=hc/\lambda$). The predicted size and shape is confirmed by experimental measurements: of the sub-picosecond time delay of the photo-electric effect, of the attenuation of undiffracted transmission through slits narrower than the soliton's diameter of $\lambda/\pi$, and by the threshold intensity required for the onset of multiphoton absorption in focussed laser beams. Inside the envelope the wave's amplitude increases linearly with the radial distance from the axis of propagation, being zero on the axis. Outside the envelope the wave is evanescent with an amplitude that decreases inversely with the radial distance from the axis. The evanescent wave is responsible for the observed double-slit interference phenomenon.Comment: 8 pages: for AIP Proceedings of QTRF-3, Quantum Theory: Reconsideration of Foundations, Vaxjo, Sweden, June 6-11, 200

STUDY CONCERNING THE AMPLITUDE OF APPLICATIVE-METHODOLOGICAL ELEMENTS IN THE MANAGERIAL DURABLE DEVELOPMENT PROCESS

The durability concept has become lately very circulated, inclusive in the economic domain, because of a more accentuated concern of people for the continuous production and consumption growth, in the context of limited character emphasis of resources and environment constrains that are more and more pressing.. It is considered viable, sustainable, durable development, only that development that satisfies the present generation’s needs, without compromising the following generations’ capacity to satisfy their own. In durable development are included a series of elements that can not miss from this development, such as: equity, education, civil rights, culture etc.model, modelling, process, durable development, management

A Development Process for Enterprise Information Systems Based on Automatic Generation of the Components

This paper contains some ideas concerning the Enterprise Information Systems (EIS) development. It combines known elements from the software engineering domain, with original elements, which the author has conceived and experimented. The author has followed two major objectives: to use a simple description for the concepts of an EIS, and to achieve a rapid and reliable EIS development process with minimal cost. The first goal was achieved defining some models, which describes the conceptual elements of the EIS domain: entities, events, actions, states and attribute-domain. The second goal is based on a predefined architectural model for the EIS, on predefined analyze and design models for the elements of the domain and finally on the automatic generation of the system components. The proposed methods do not depend on a special programming language or a data base management system. They are general and may be applied to any combination of such technologies

Gold and Displacement in Eastern Europe: Risks and Uncertainty at Roşia Montană

The Canadian-Romanian gold mining project at Roşia Montanǎ in Romania is known as the largest opencast gold mine being planned now in Europe. It involves the displacement of several thousand inhabitants, mostly former gold miners and a smaller number of farmers. The land and houses of more than three quarters of this population have already been acquired by the project owners, although the project has not yet received its formal environmental clearance. The paper analyzes the risks facing the displaced population of Roşia Montană, employing as analytical methodology the Impoverishment Risks and Reconstruction (IRR) model, developed by Michael M. Cernea. The paper argues for an expansion of the IRR model. By taking into account the macro (extralocal) forces that shape displacement and paying closer attention to the micro (subjective) experience of this process, it becomes possible to understand the effects of uncertainty and vulnerability in displacement. The author's participant observations and in-depth interviews with local families are complemented with secondary analyses of data from several other socio-economic surveys and with the analysis of the Resettlement and Relocation Action Plan of the project owners

Branching Off: The Early Moderns in Quest for the Unity of Knowledge

As Francis Bacon put it on the frontispiece of his Novum Organum, grafting an apocalyptic vision on a research program, multi pertransibunt et multiplex erit scientia. The development of science becomes steadily associated with the end of earthly life, a theme that would resound deeply in Western thought up until Goethe’s Faust. What grounds then the multiplicity of knowledge? What is the common trunk out of which all realms of knowledge unfold, like the burgeoning branches of the celebrated tree? After the Augustinian imprint of the first Christian centuries and after the admirable effort of the high scholastics’ Aristotelian and Christian synthesis, the seventeenth century undertakes new scientific work with the need of a new steady ground. All the big names of the modern era, Francis Bacon, Galileo, Descartes, Robert Boyle, Spinoza or Leibniz, found themselves engaged in the search for a common trunk of wisdom, each of them nourishing the intimate conviction that they possessed the philosophical core which would satisfy the learned men’s newly found appetite for indefinitely extending knowledge. In doing this, all of these masters needed to confront the philosophical tradition that they received, reworking and merging together the old structures of science through this epistemological prism of the search for the unity of knowledge. (Vlad Alexandrescu)