Return to Dollar, Generalized Distance Function and the Fisher Productivity Index

Exploring the duality between a return to dollar definition of profit and the generalized distance function we establish the relationship between the Laspeyres, Paasche and Fisher productivity indexes and their alternative Malmquist indexes counterparts. By proceeding this way, we propose a consistent decomposition of these productivity indexes into two mutually exclusive components. A technical component represented by the Malmquist index and an economical component which can be identified with the contribution that allocative criteria make to productivity change. With regard to the Fisher index, we indicate how researchers can further decompose the Malmquist technical component rendering explicit the sources of productivity change. We also show how the proposed model can be implemented by means of Data Envelopment Analysis techniques, and illustrate the empirical process with an example data set.Generalized Distance Function; Return to Dollar; Fisher and Malmquist Productivity Indexes

Generic Battery Model based on a Parametric Implementation

Batteries are a common element used in many electronic applications. Therefore, the analysis and simulation of these applications requires a battery model in order to validate the behavior of the whole system. Since batteries are based on different technologies, a modeling approach valid for any technology is a potential good alternative. Since there are similarities among the different technologies, it is possible to address the modeling of batteries as generic energy storage elements with particular differences. This work presents a battery model valid for different technologies based on a parametric implementation

Modelling the spatial and sectoral benefits of productivity enhancing innovations using a transport oriented multiregional IO framework: the ‘megatruck’ in Spain

We render operational the model outlined by Carter (1990) via the introduction of the research methods necessary for studying the spatial and sectoral (upstream and downstream) benefits of productivity-enhancing innovations within a real interregional input–output framework. As case study we examine the reduction in production costs derived from the adoption of longer and heavier vehicles in freight road transportation. We exploit a new Spanish regional table including a detailed disaggregation of the transportation sector. The productivity gains at the national level, resulting from a 30% reduction in transport costs, amount to 2.95% of the GVA at market prices. Results show that firms operating in this niche market appropriate most of the gross operation surplus (which increases by 10%), consistent with the existence of market power. The remaining transportation sectors see profits slightly worsened, suggesting limited substitution effects. A high regional heterogeneity exists because of the different input–output structuresThis work was supported by Ministerio de Fomento, Spain: [Grant Number P42-08

Quantitative determination of the antitumor alkyl ether phospholipid edelfosine by reversed-phase liquid chromatography-electrospray mass spectrometry: application to cell uptake studies and characterization of drug delivery systems.

Edelfosine is a synthetic alkyl ether phospholipid that represents a promising class of antitumor agents. However, analytical methods to measure these type compounds are scarce. The lack of a reliable methodology to quantify edelfosine is a major problem in ongoing and scheduled preclinical and clinical trials with this drug. We evaluated the applicability of high-performance liquid chromatography–mass spectrometry to determine edelfosine in biological samples and polymeric delivery systems. Sample pre-treatment involved polymer precipitation or cell lysis with methanol. HPLC separation was performed on an Alltima RPC18 narrow-bore column and edelfosine quantification was done by electrospray ionization mass spectrometry (ESI-MS) using positive ion mode and selected ion monitoring. Assays were linear in the tested range of 0.3–10 μg/ml. The limit of quantification was 0.3 ng/sample in both matrices, namely biological samples and polymeric delivery systems. The interassay precision ranging from 0.79 to 1.49%, with relative errors of −6.7 and 12.8%. Mean extraction recovery was 95.6%. HPLC–ESI-MS is a reliable system for edelfosine analysis and quantification in samples from different sources, combining advantages of full automation (rapidity, ease of use, no need of extensive extraction procedures) with high analytical performance and throughput

DC/DC Converter Parametric Models for System level Simulation

The objective of this work is to propose a whole solution for simulating power systems based on the use of behavioral DC/DC converter models. The proposed model is a generic model whose parameters can be obtained from data sheets (especially useful to model commercial converters) or equivalent tests. The model has configurable features which can be activated or disabled in order to perform optimal simulations or to generate models with different levels of abstraction to be used in a top-down design methodology

Modeling and Simulation Requirements for the Analysis and Design of DC Distributed Power Electronics Systems

The objective of this paper is to establish which are the requirements of the component models in a distributed power system in order to satisfy the necessities of the system architect. Based on the information that will help the designer to make the right decision for its architecture and the selection of their components, different levels of modeling will be required for each simulation. The paper also shows the implication of the modeling approach on the requirements for the simulator and the description language

Robustness Analysis of DC Distributed Power Systems by Means of Behavioral DC-DC Converter Models

The aim of this paper is to determine the model requirements for dc-dc converters in order to analyze and evaluate the performance of different architectures of DC distributed power systems and to assure that all the specifications are met under all parameter variations. Based on these requirements a parametric model for the dc-dc converters is presented that can be identified as a function of the information given by the manufacturers in their datasheets. In this way, it is possible to make sensitivity and worst case analysis that can help the designer to evaluate the robustness of their architectures

Top-down methodology employing hardware description languages (HDLs) for designing digital control in power converters

This paper presents a research line oriented to develop methodologies that takes advantage of hardware description languages in order to simplify the design of power converters that employ digital control techniques. The methodology focuses on setting the adequate communications among subsystems in order to simplify the change of the levels of abstraction of the subsystem’s models (from the conceptual level to the actual electric + synthesizable code). Changing the level of abstraction in the design process pretends: first to provide useful models at early designing steps; second, to optimize the simulation of the system, and at same time optimize the verification step

A Parametrization Tool for Power Electronics Design at System Level

This paper describes a parameterization software used for the generation of behavioral models of power converters. This tool eases the capture and generation of fast and accurate models based on the information provided by manufacturers and measures. The models incorporate many behavioral features and can be used at different levels in the analysis, design and verification of complete power distribution systems like aircraft and automotive power systems. Simulations of common tests of power systems are presented to show the functionality of the models