Search results for "principal"
showing 10 items of 795 documents
Strong enhancement of Penning ionization for asymmetric atom pairs in cold Rydberg gases: the Tom and Jerry effect
2016
We consider Penning ionization of Rydberg atom pairs as an Auger-type process induced by the dipole–dipole interaction and employ semiclassical formulae for dipole transitions to calculate the autoionization width as a function of the principal quantum numbers, n d , n i , of both atoms. While for symmetric atom pairs with the well-known increase of the autoionization width with increasing n 0 is obtained, the result for asymmetric pairs is counterintuitive—for a fixed n i of the ionizing atom of the pair, the autoionization width strongly increases with decreasing n d of the de-excited atom. For H Rydberg atoms this increase reaches two orders of magnitude at the maximum of the n d depende…
Geographic Distribution and Niche Divergence of Two Stinkbugs,Parastrachia japonensisandParastrachia nagaensis
2014
Parastrachiidae is a small stinkbug family containing only one genus and two species, Parastrachia japonensis (Scott) (Hemiptera: Heteroptera: Pentatomoidea) and Parastrachia nagaensis Distant. The geographic distribution of the genus has been poorly studied. Niche conservatism refers to that idea that closely related species are more ecologically similar than would be expected, whereas niche divergence predicts they occupy distinct niche spaces. The existence of only two species within one genus suggests niche conservatism or differentiation might exist among them. Herein, the distribution of the genus was mapped, potential distributions were predicted using ecological niche modeling, and …
Object and subject of evasion of taxes and other compulsory payments
2014
The paper is devoted to such topical issue of Criminal Law as Object and Subject of Evasion of Taxes and Other Compulsory Payments. There are analyzed researched crime determination problems, which are connected with subject and object of tax and other compulsory payments evasion. In the course of the research, the author has made the conclusions that the object of the evasion of taxes and other compulsory payments group is the national economic interests. The direct object is the national economic interests in the sphere of state revenues or the national fiscal interests. While analyzing the law and regulations it is concluded that the subject of the evasion of taxes and other compulsory p…
The onset of convection in a two-layered porous medium with anisotropic permeability
2019
We consider convection in a horizontal porous layer of uniform thickness which is heated from below and which is composed of two anisotropic sublayers with principal axes lying in the three coordinate directions. The aim is to determine criteria for the onset of convection by finding the critical Rayleigh number, wavenumber and roll orientation relative to the coordinate axes. The full set of nondimensional parameters has at least six members even when the sublayers are considered to be thermally isotropic, and therefore, we select some special cases in order to illuminate the type of qualitative behaviour which may be expected. One such case is where the anisotropic sublayers are identical…
Risk Aversion in the Board Room. An Analytical Approach on Corporate Governance of German Stock–Listed Companies
2017
According to the agency theory, a positive relationship between company performance and good corporate governance should exist. A broader study of the author of this paper examines a sample of German stock–listed companies whereas Germany can be seen as one of the most highly regulated countries concerning corporate governance. The overall purpose of the author's study is to analyze the effect of supervisory board characteristics and procedures on firm performance. Several corporate governance variables such as number of committees, board independency, supervisory board compensation, personal risk liability, etc. are examined regarding their effects on firm performance in terms of firm grow…
Corporate governance and firm performance: A comparative analysis of auditing problems
2006
The recent financial crises have created a new debate about comparison and convergence of different systems of corporate governance. In particular, they have underlined poor efficiency of rule structures to achieve a good relationship between different stakeholder’s rights. In line with many studies of corporate governance that emphasize the manager-stakeholders relationship as explained by agency theory, in this paper, I analyse the role of auditing as an incentive device to reduce contractual or transaction costs related to asymmetric information.Considering as a benchmark the recent US Sarbanes Oxley Act of July 2002. I describe a set of auditing principles by comparing common and civil …
Multiple Blockholders and Firm Value: A Simulation Analysis
2023
In this paper, we analyse the relationship between the distribution of ownership and firm value in the presence of multiple blockholders. In recent years, the topic has attracted the attention of many scholars. Yet, the empirical evidence on the relationship between the distribution of ownership among large shareholders and firm value has been non-conclusive and contradictory. We focus on the interaction between a controlling block of shareholders and a non-controlling block that can monitor the largest controlling block. We develop and simulate a simple model combining the two effects related to the presence of additional blockholders that can monitor the largest controlling block of share…
Multivariate analysis in the identification of biological targets for designed molecular structures: The BIOTA protocol
2013
In this work the new protocol BIOlogical Target Assignation (BIOTA) for the prediction of the biological target from molecular structures is proposed. BIOTA is based on the Principal Components Analysis (PCA) application on a matrix of ligands versus molecular descriptors. The application of BIOTA could allow to hypothesize the mechanism of action of a candidate drug prior to its biological evaluation or to repurpose old drugs. The protocol can be fine-tuned by choosing opportune targets (biological or not) and molecular descriptors, and it can be useful in every fields in with it is possible to collect set of compounds with known properties. The robustness of the protocol depends from diff…
Deficiencias epistemológicas en la enseñanza habitual de los conceptos de campo y potencial eléctrico
1997
This article intends to analyse up to what extent the scarce learning produced when introducing the basic concepts on electrostatics is due to deficiencies and inadequacies in its routine teaching. So, on the one hand, we analyse what have been the principal epistemological leaps forward in the making of electricity as a science. On the other hand, we analyse Physics books and the teachers’ opinions.
Cost Reduction in Irrigation Networks by an Efficient Use of Pressure Reducing Valves
1992
The cost effective design of hydraulic networks has been traditionally studied from the point of view of the relationship between hydraulic variables and economic parameters, with piping being the main element studied. The reason is clear: the piping is by far the most costly item of a projected network. However it is not usual to find an explicit consideration of the influence that pipe thickness has on the cost of the network because of the added difficulty that this aspect poses to formulating the problem of optimization. In irrigation networks, which are typically branched, it is advisable to place Pressure Reducing Valves (PRV’s) to fulfil three main goals: 1) to control the flow rate …