Proteccionismo y diferenciación de productos

This paper tries to measure the costs of a trade war between countries and/or blocks under product differentiation, and compare them with the outcomes when all tradeable products are homogeneous (Krugman, 1991 a). For this, I use a model of monopolistic competition (Krugman, 1980) in which the consumers have a preference for diversity and the economies of scale aren't determining factor. In developing the model, I take three different scenarios into account: decrease in the number of varieties, imposition of tariffs, and both at the same time.Este artículo intenta reflejar los costes de una guerra comercial entre países y/o bloques bajo diferenciación de productos. Una vez obtenidos, se proceden a comparar con los que tendrían lugar en un escenario donde todos los bienes comerciados son homógeneos (Krugman, 1991 a). Para obtener los costes del proteccionismo en un escenario de diferenciación de productos utilizo un modelo de competencia monopolística (Krugman, 1980), donde los consumidores tienen preferencia por la variedad y el aprovechamiento de las economías de escala no es un factor significativo. En el desarrollo del modelo, considero tres escenarios: reducción en el número de variedades importadas, imposición de aranceles y ambas políticas a la vez

Las apropiaciones de la ciudad a la hora de la globalización: las estrategias del capital ruso y chino en el mercado inmobiliario de Barcelona

[spa]Con la internacionalización del mercado inmobiliario de las ciudades, originariamente local, se han generado nuevos flujos de capital que han reforzado a nivel mundial el segundo circuito. Barcelona, por lo menos desde 1992 no ha sido ajena a ello. Los últimos capitales llegados proceden de antiguos países socialistas, especialmente de la República Popular de China y de Rusia, con estrategias distintas de localización, más concentradas las chinas. Las consecuencias de estas nuevas apropiaciones del espacio urbano se sienten en la restricción del acceso al mercado de la vivienda por parte de los ciudadanos y en la formación de una Chinatown de modelo europeo.[eng]With the internationalization of the urban real estate market, originally local, have generated new capital flows worldwide that have reinforced the second circuit. Barcelona, at least since 1992 has not been immune to it. The latest arrivals come from former socialist countries, especially from the People's Republic of China and Russia, with more concentrated Chinese different localization strategies. The consequences of these new appropriations of urban space are restricting access to the housing market to the citizens and the formation of a European model of Chinatown

Automatic Adaptation of Airport Surface Surveillance to Sensor Quality

This paper describes a novel method to enhance current airport surveillance systems used in Advanced Surveillance Monitoring Guidance and Control Systems (A-SMGCS). The proposed method allows for the automatic calibration of measurement models and enhanced detection of nonideal situations, increasing surveillance products integrity. It is based on the definition of a set of observables from the surveillance processing chain and a rule based expert system aimed to change the data processing method

Experimentel ADS-B based surveillance

This paper describes an ADS-B implementation in air-to-air and ground based experimental surveillance within a prototype ATM system. The relations between airborne and ground systems related to surveillance are detailed, and the prototype surveillance systems and their algorithms described. Their performance is analysed, based both on simulated and real data

Generic multisensor multitarget bias estimation architecture

Current bias estimation algorithms for air traffic control (ATC) surveillance are focused on radar sensors, but the integration of new sensors (especially automatic dependent surveillance-broadcast and wide area multilateration) demands the extension of traditional procedures. This study describes a generic architecture for bias estimation applicable to multisensor multitarget surveillance systems. It consists on first performing bias estimations using measurements from each target, of a subset of sensors, assumed to be reliable, forming track bias estimations. All track bias estimations are combined to obtain, for each of those sensors, the corresponding sensor bias. Then, sensor bias terms are corrected, to subsequently calculate the target or sensor-target pair specific biases. Once these target-specific biases are corrected, the process is repeated recursively for other sets of less reliable sensors, assuming bias corrected measures from previous iterations are unbiased. This study describes the architecture and outlines the methodology for the estimation and the bias estimation design processes. Then the approach is validated through simulation, and compared with previous methods in the literature. Finally, the study describes the application of the methodology to the design of the bias estimation procedures for a modern ATC surveillance application, specifically for off-line assessment of ATC surveillance performance

Bias Estimation for Evaluation of ATC surveillance systems

This paper describes an off-line bias estimation and correction system for air traffic control related sensors, used in a newly developed Eurocontrol tool for the assessment of ATC surveillance systems. Current bias estimation algorithms are mainly focused in radar sensors, but the installation of new sensors (especially automatic dependent surveillance-broadcast and wide area multilateration) demands the extension of those procedures. In this paper bias estimation architecture is designed, based on error models for all those sensors. The error models described rely on the physics of the measurement process. The results of these bias estimation methods will be exemplified with simulated data

Automatic-dependent surveillance-broadcast experimental deployment using system wide information management

This paper describes an automatic-dependent surveillance-broadcast (ADS-B) implementation for air-to-air and ground-based experimental surveillance within a prototype of a fully automated air traffic management (ATM) system, under a trajectory-based-operations paradigm. The system is built using an air-inclusive implementation of system wide information management (SWIM). This work describes the relations between airborne and ground surveillance (SURGND), the prototype surveillance systems, and their algorithms. System's performance is analyzed with simulated and real data. Results show that the proposed ADS-B implementation can fulfill the most demanding surveillance accuracy requirements

Air-to-Air Surveillance for Future ATM Systems

This paper describes a prototype implementation of ADS-B in an air-to-air surveillance system. This air surveillance system was defined for an experimental project on future civilian air traffic management, which imposes new requirements over both air and ground surveillance systems. In this paper the relation between the different airborne and ground systems related to air surveillance is detailed, and the air surveillance and its algorithms are described. It is related with current ADS-B and TIS-B proposals, and defined as an extension of those systems. Finally, performance of the air surveillance is detailed, based on simulated scenarios, and some conclusions for future enhancements of ADS-B function are derived