22,359 research outputs found
Expanded Very Large Array observations of the H66{\alpha} and He66{\alpha} recombination lines toward MWC 349A
We have used the greatly enhanced spectral capabilities of the Expanded Very
Large Array to observe both the 22.3 GHz continuum emission and the H66{\alpha}
recombination line toward the well-studied Galactic emission-line star MWC
349A. The continuum flux density is found to be 411 41 mJy in good
agreement with previous determinations. The H66{\alpha} line peak intensity is
about 25 mJy, and the average line-to-continuum flux ratio is about 5%, as
expected for local thermodynamic equilibrium conditions. This shows that the
H66{\alpha} recombination line is not strongly masing as had previously been
suggested, although a moderate maser contribution could be present. The
He66{\alpha} recombination line is also detected in our observations; the
relative strengths of the two recombination lines yield an ionized helium to
ionized hydrogen abundance ratio y+ = 0.12 0.02. The ionized helium
appears to share the kinematics of the thermally excited ionized hydrogen gas,
so the two species are likely to be well mixed. The electron temperature of the
ionized gas in MWC 349A deduced from our observations is 6,300 600 K.Comment: Accepted for publication in ApJ
Efficiency Measures and Regulation: An Illustration of the Gas Distribution Sector in Argentina
The paper develops a cost frontier model of gas distribution and estimates it on data for gas distribution companies of Argentina. Efficiency measures are an important tool for regulators, showing how much a firm can rise its output without using more inputs. In Argentina, the Regulatory Framework of the gas sector establishes that only firms that are efficient can earn a rate of return similar to those activities that bear comparable risk. In this context, the estimate of efficiency measures is an indispensable tool to improve regulation of the privatised utilities. The first part of the paper consists in a theoretical survey of the existent literature where we discuss recent developments in this field, paying special attention to the case of regulated utilities. Deterministic and stochastic cost frontiers are analysed, both for the cases of cross-section and panel data. In the second part, we use econometrics methods to estimate a cost frontier (deterministic and stochastic) for the gas distribution sector in Argentina. Finally, the efficiency rankings of the companies are estimated.Efficiency Measures; Gas Distribution Sector in Argentina
Pricing to Market at firm level
This paper tries to contribute to the renewed literature about price differences across countries (the so-called border effect). Specifically, it analyzes the reasons underlying changes in relative prices across export/domestic markets for an open economy. The theoretical benchmark, based on the existence of Pricing to Market strategies, also takes into account some hypotheses about the effects of demand variations and market power on prices. The empirical analysis, using firm panel data for the nineties, points out the positive (though small) impact of the exchange rate on the evolution of price ratio. Additionally, the results also suggest a procyclical behavior of prices in both markets, which is positively affected by the degree of competition. Though data do not allow an in-depth analysis, some hypothesis in terms of foreseeable effects of the European Monetary Union on relative prices are provided.
Technical Change and Catching-up: The Electricity Distribution Sector in South America
The main purpose of this paper is to analyze technical change in the electricity distribution sector in South America, in the period 1994-1997. We do so by estimating a Maximum Likelihood stochastic frontier. We found that there is no evidence of catching up effects in the sector during this period. Besides, there is partial evidence that suggests that countries which reformed their electricity sector had a better performance than those which did not. We also found an increase in the capital share in the countries that made the reform and an increment in the labor share in the ones that did not make the reform.Technical change; Catching-Up; Stochastic frontier
Domestic and foreign price-marginal cost margins: an application to Spanish manufacturing firms
The objective of this paper is to analyse the differences in price-marginal cost margins of the export and domestic markets by the estimation of a multiproduct cost function. We apply this method to a panel of Spanish export manufacturing firms from the period 1990-1997. Some results emerge from the estimations. First, price-marginal cost margins in domestic markets are larger than foreign margins throughout the period. Second, price-marginal cost margins are procyclical in the domestic market but there is no evidence of this behaviour in the foreign markets. Third, there is no evidence that export firms used the devaluation of the currency to increase their margins. Finally, price-cost margins reveal some degree of heterogeneity across industries in both markets.Marginal cost, price-cost margins, translog cost function, export firm
Consistency Conditions: Efficiency Measures for the Electricity Distribution Sector in South America
The main goals of this paper are basically two: to compare the relative efficiency of the firms in the electricity distribution sector in South America, and to perform a consistency analysis on the different approaches usually used to measure efficiency. The estimated model considers a single output (customers) and six variables standing for inputs and environmental characteristics (service area, sales, market structure, mains kilometres of distribution, number of employees and transformer capacity). Information on these variables comes from the CIER database for the accounting year ending in 1994. This model is in line with the previous literature on the subject. It has been found that, in general, the consistency conditions are met.Consistency Conditions; Efficiency Measures; Electricity Distribution Sector
Foreign direct investment. A bid for progress?
Foreign Direct Investment (FDI) is not a unique explanation for growth and progress, but is one of the more useful indicators of the open opportunities. It reveals preferences of the developed countries’ private sector, while the emerging economies seem to participate in a global bid. That bid is for capital, for the technology and know-how normally associated to investments, and for the final award, progress and development. Besides policies, politics and initial conditions, the economy matters. An estimation of economic determinants to FDI is done, and to take into account best relative results, an econometric frontier is calculated in order to determine how do the more efficient in attracting FDI. Some new perspective is added to conventional wisdom: there are countries, which are in some sense “more efficient producers” of FDI. The efficient frontier approach could shed some light of the link from sowing to reaping. Some shocking results were attained, when we tried to ask the question “Which are the best harvesters?” The more “sexiest” countries are not the more efficient producers of FDI in our ranking.Foreign Direct Investment, efficiency frontiers, growth
Determinants of tourism destination competitiveness in the countries most visited by international tourists: Proposal of a synthetic index
Tourism destination competitiveness is a multidimensional concept that is widely studied in the academic literature, but multiple factors make its measurement a difficult task. In this article, we design a synthetic index to rank the 80 countries that attract the majority of international tourists by level of tourism competitiveness. In order to do this, we use all of the simple variables included in the 2017 Travel & Tourism Competitiveness Index, proposing a new methodology for the construction of this synthetic index, which it solves the problems of aggregation of variables expressed in different measures, arbitrary weighting and duplicity of information; issues that remain unresolved by the TTCI. Likewise, we analyse the most influential dimensions in tourism competitiveness. Air transport infrastructures, cultural resources and ICT readiness are the key dimensions that explain the main disparities.Funding Agency
Spanish Ministry of Economy, Industry and Competitiveness
State Research Agency (SRA)
European Union (EU)
ECO2017-86822-Rinfo:eu-repo/semantics/publishedVersio
The Cost of Capital in Regulated Firms: The Argentine Experience
The sustainability of service is one of the fundamental aims of any regulatory system, and this tends to be reflected in the general principles within the legal framework of each public service. The necessity to cover economic costs of service then follows, in order to cover costs in such a way as to guarantee the maintaining and continuity of the system as well as its expansion. These economic costs should necessarily include sufficient retribution for the capital used by investors: the cost of capital. In the case of Argentine regulation, it is usual practice to use an adapted form of the CAPM (Capital Asset Pricing Model) to calculate the opportunity cost of equity, in such a way as to take the country risk into account. In this work we will analyse the components of the adapted formula for the cost of capital, discussing incentives which generate each of the possible outcomes for the regulated firms. Finally, we will present a model of dynamic optimisation for a regulated firm in a country such as Argentina.regulatory system; public service; CAPM; country risk
Organic Molecules in the Galactic Center. Hot Core Chemistry without Hot Cores
We study the origin of large abundances of complex organic molecules in the
Galactic center (GC). We carried out a systematic study of the complex organic
molecules CH3OH, C2H5OH, (CH3)2O, HCOOCH3, HCOOH, CH3COOH, H2CO, and CS toward
40 GC molecular clouds. Using the LTE approximation, we derived the physical
properties of GC molecular clouds and the abundances of the complex
molecules.The CH3OH abundance between clouds varies by nearly two orders of
magnitude from 2.4x10^{-8} to 1.1x10^{-6}. The abundance of the other complex
organic molecules relative to that of CH3OH is basically independent of the
CH3OH abundance, with variations of only a factor 4-8. The abundances of
complex organic molecules in the GC are compared with those measured in hot
cores and hot corinos, in which these complex molecules are also abundant. We
find that both the abundance and the abundance ratios of the complex molecules
relative to CH3OH in hot cores are similar to those found in the GC clouds.
However, hot corinos show different abundance ratios than observed in hot cores
and in GC clouds. The rather constant abundance of all the complex molecules
relative to CH3OH suggests that all complex molecules are ejected from grain
mantles by shocks. Frequent (similar 10^{5}years) shocks with velocities >6km/s
are required to explain the high abundances in gas phase of complex organic
molecules in the GC molecular clouds. The rather uniform abundance ratios in
the GC clouds and in Galactic hot cores indicate a similar average composition
of grain mantles in both kinds of regions. The Sickle and the Thermal Radio
Arches, affected by UV radiation, show different relative abundances in the
complex organic molecules due to the differentially photodissociation of these
molecules.Comment: 18 pages, 10 Postscript figures, uses aa.cls, aa.bst, 10pt.rtx,
natbib.sty, revsymb.sty revtex4.cls, aps.rtx and aalongtabl.sty. Accepted in
A&A 2006. version 2. relocated figures and tables. Language editor
suggestions. added reference
- …