Origins and efficiency of the electric industry regulation in Spain, 1910-1936

The aim of this paper is to discover the origins of utility regulation in Spain, and to analyse, from a microeconomic perspective, its characteristics and the impact of regulation on consumers and utilities. Madrid and the Madrilenian utilities are taken as a case study. The electric industry in the period studied was a natural monopoly2. Each of the three phases of production, generation, transmission and distribution, had natural monopoly characteristics. Therefore, the most efficient form to generate, transmit and distribute electricity was the monopoly because one firm can produce a quantity at a lower cost than the sum of costs incurred by two or more firms. A problem arises because when a firm is the single provider it can charge prices above the marginal cost, at monopoly prices. When a monopolist reduces the quantity produced, price increases, causing the consumer to demand less than the economic efficiency level, incurring a loss of consumer surplus. The loss of the consumer surplus is not completely gained by the monopolist, causing a loss of social surplus, a deadweight loss. The main objective of regulation is going to be to reduce to a minimum the deadweight loss. Regulation is also needed because when the monopolist fixes prices at marginal cost equal marginal revenue there would be an incentive for firms to enter the market creating inefficiency. The Madrilenian industry has been chosen because of the availability of statistical information on costs and production. The complex industry structure and the atomised demand add interest to the analysis. This study will also provide some light on the tariff regulation of the period which has been poorly studied and will complement the literature on the US electric utilities regulation where a different type of regulation was implemented.

Extensional flow of nematic liquid crystal under electric field gradient

Systematic asymptotic methods are used to formulate a model for the extensional flow of a thin sheet of nematic liquid crystal. With no external body forces applied, the model is found to be equivalent to the so-called Trouton model for Newtonian sheets (and fi bers), albeit with a modi fied "Trouton ratio". However, with a symmetry-breaking electric field gradient applied, behavior deviates from the Newtonian case, and the sheet can undergo fi nite-time breakup if a suitable destabilizing field is applied. Some simple exact solutions are presented to illustrate the results in certain idealized limits, as well as sample numerical results to the full model equations.

Estimation of zero-sequence impedance of undergrounds cables for single-phase fault location in distribution systems with electric arc

This paper focus on the problem of locating single-phase faults in mixed distribution electric systems, with overhead lines and underground cables, using voltage and current measurements at the sending-end and sequence model of the network. Since calculating series impedance for underground cables is not as simple as in the case of overhead lines, the paper proposes a methodology to obtain an estimation of zero-sequence impedance of underground cables starting from previous single-faults occurred in the system, in which an electric arc occurred at the fault location. For this reason, the signal is previously pretreated to eliminate its peaks voltage and the analysis can be done working with a signal as close as a sinus wave as possible

Modification of the Perrine-Baum diagram to improve the calculation of high voltage electric lines

Through the history of Electrical Engineering education, vectorial and phasorial diagrams have been used as a fundamental learning tool. At present, computational power has replaced them by long data lists, the result of solving equation systems by means of numerical methods. In this sense, diagrams have been shifted to an academic background and although theoretically explained, they are not used in a practical way within specific examples. This fact may be against the understanding of the complex behavior of the electrical power systems by students. This article proposes a modification of the classical Perrine-Baum diagram construction to allowing both a more practical representation and a better understanding of the behavior of a high-voltage electric line under different levels of load. This modification allows, at the same time, the forecast of the obsolescence of this behavior and line’s loading capacity. Complementary, we evaluate the impact of this tool in the learning process showing comparative undergraduate results during three academic years

A comparative analysis of two methods for the calculation of electric-field-induced perturbations to molecular vibration

Two common methods of accounting for electric-field-induced perturbations to molecular vibration are analyzed and compared. The first method is based on a perturbation-theoretic treatment and the second on a finite-field treatment. The relationship between the two, which is not immediately apparent, is made by developing an algebraic formalism for the latter. Some of the higher-order terms in this development are documented here for the first time. As well as considering vibrational dipole polarizabilities and hyperpolarizabilities, we also make mention of the vibrational Stark effec

A quantum molecular similarity analysis of changes in molecular electron density caused by basis set flotation and electric field application

Quantum molecular similarity (QMS) techniques are used to assess the response of the electron density of various small molecules to application of a static, uniform electric field. Likewise, QMS is used to analyze the changes in electron density generated by the process of floating a basis set. The results obtained show an interrelation between the floating process, the optimum geometry, and the presence of an external field. Cases involving the Le Chatelier principle are discussed, and an insight on the changes of bond critical point properties, self-similarity values and density differences is performed

The drive for quality - the impact on accounting in the wine industry

There is a substancial literature on the accounting procedures needed to trackdown the costs of quality control and quality failure. In a drive for improved quality the changes in the process of production or service delivery will also give rise to new accounting needs. In this article we take one example of an industry, wine production, where in most countries there has been a movement towards expanding higher quality production. We report on interviews with wine producers in the US, Australia, Canada, New Zealand and Spain, and identify avariety of ways in which a more sophisticated approach to accounting has become necessary as a result of the drive for quality.

The electric revolution in Latin America

Latin America participated in the electric revolution which profoundly transformed the most developed Western economies between 1880 and 1930. The electrification of Latin America began relatively soon after these economies, but it was incapable of keeping up with them. Public electric lighting was introduced early in the big Latin American cities, where electric trams started running at almost the same time as in Europe, and electricity spread rapidly in the mining sector. In the most advanced countries or areas in the region, the manufacturing industry substituted the steam engine with the electric motor, following the example of industry in the United States and Europe. Nevertheless, towards 1930 electricity consumption per inhabitant for Latin America was far below that of the more advanced economies, and only the Latin American countries which lead the process of electrification had reached levels of electric consumption that were similar to those of the late industrialised European countries. One of the most striking features of the electric revolution in Latin America is rooted precisely in the enormous national differences. These differences are indicative of the great economic inequalities existing in the heart of the region and these nations highly diverse capacity for economic modernisation.

Pla de màrqueting per al llançament d'un nou producte en el mercat dels motors elèctrics per a bancs de proves

Ningú no dubte ja del canvi de mentalitat que s’ha produït en els darrers anys en els compradors pel què fa al mercat de l’automòbil. La seguretat i el respecte per el medi ambient, són actualment dos dels factors claus que el consumidor té en compte a l’hora de comprar un vehicle. D’altra banda en els darrers anys la Unió Europea, ha fixat tota una sèrie normatives per tal de reduir les emissions nocives a l’atmosfera. Així doncs, més seguretat i menys emissions, signifiquen vehicles que incorporin components i sistemas cada cop més sofisticats, els quals, a la vegada, necessiten de bancs d’assaig i equips de test per tal de ser validats. Aquest fet ha provocat una revolució dins dels sistemes de test per a vehicles, per als quals han augmentat enormement les exigències en quan a precisions i repetibilitat per tal d’intentar reproduir, amb la màxima fiabilitat possible, les condicions de treball que hauran de suportar els components durant el seu ús real. Les característiques dels motors elèctrics, resulten ideals per a accionar aquest tipus d’aplicacions, ja que permeten un control del parell molt acurat i una repetibilitat quasi perfecte enfront d’altres sistemas utilitzats fins no fa massa temps. Aquesta demanda creixent d’aquest tipus de màquines elèctriques, obra una nova oportunitat de negoci per a les empreses fabricants de motors elèctrics. L’objectiu principal d’aquest treball és identificar i satisfer les necessitats dels clients, dins d’un mercat industrial concret: el mercat dels motors elèctrics per a bancs de proves de components per a la indústria de l’automoció. La fita és doncs la de proporcionar les eines necessàries per tal de que una empresa, fabricant de motors elèctrics de velocitat variable, pugui realitzar el disseny, desenvolupament i llançament comercial d’un nou tipus de motor, específicament pensat per aquest mercat, amb les màximes garanties d’èxit. Com a principal conclusió, el treball argumenta que el nou producte representa una oportunitat de negoci força atractiva i rendible per a l’empresa, i permetrà diversificar la oferta de la companyia cap a un nou sector fins ara no explotat.

Multiple edges of a quantum Hall system in a strong electric

In this paper we show that if the electrons in a quantum Hall sample are subjected to a constant electric field in the plane of the material, comparable in magnitude to the background magnetic field on the system of electrons, a multiplicity of edge states localized at different regions of space is produced in the sample. The actions governing the dynamics of these edge states are obtained starting from the well-known Schrödinger field theory for a system of nonrelativistic electrons, where on top of the constant background electric and magnetic fields, the electrons are further subject to slowly varying weak electromagnetic fields. In the regions between the edges, dubbed as the "bulk," the fermions can be integrated out entirely and the dynamics expressed in terms of a local effective action involving the slowly varying electromagnetic potentials. It is further shown how the bulk action is gauge noninvariant in a particular way, and how the edge states conspire to restore the U(1) electromagnetic gauge invariance of the system. In the edge action we obtain a heretofore unnoticed gauge-invariant term that depends on the particular edge. We argue that this term may be detected experimentally as different edges respond differently to a monochromatic probe due to this term

Electric-field control of exchange bias in multiferroic epitaxial heterostructures

The magnetic exchange between epitaxial thin films of the multiferroic (antiferromagnetic and ferroelectric) hexagonal YMnO3 oxide and a soft ferromagnetic (FM) layer is used to couple the magnetic response of the FM layer to the magnetic state of the antiferromagnetic one. We will show that biasing the ferroelectric YMnO3 layer by an electric field allows control of the magnetic exchange bias and subsequently the magnetotransport properties of the FM layer. This finding may contribute to paving the way towards a new generation of electric-field controlled spintronic devices.

Pair production by and electric field in (1+1)-dimensional de Sitter space

We use the method of Bogolubov transformations to compute the rate of pair production by an electric field in (1+1)-dimensional de Sitter space. The results are in agreement with those obtained previously using the instanton methods. This is true even when the size of the instanton is comparable to the size of the de Sitter horizon.

Tuning synchronization of integrate-and-fire oscillators through mobility

We analyze the emergence of synchronization in a population of moving integrate-and-fire oscillators. Oscillators, while moving on a plane, interact with their nearest neighbor upon firing time. We discover a nonmonotonic dependence of the synchronization time on the velocity of the agents. Moreover, we find that mechanisms that drive synchronization are different for different dynamical regimes. We report the extreme situation where an interplay between the time scales involved in the dynamical processes completely inhibits the achievement of a coherent state. We also provide estimators for the transitions between the different regimes.