Economies of Scale and Spatial Scope in the European Airline Industry

In this article we use four different indices to measure cost performance of the European Airline Industry. By using the number of routes as an indicator of Network Size, we are able to estimate indicators of Economies of Scale and Spatial Scope. By estimating total and variable cost functions we are also able to calculate an index of the excess capacity of the firms. For this purpose, we use data from the years 1984 to 1998, a period during which several deregulation measures were imposed on the European airline industry. Some of the implications of this deregulation process for the cost performance of the industry are presented and discussed. Our results suggest that in the year 1998, almost all the firms had Economics of Density in their existing networks, while several of the firms also had Economies of Scale and Economies of Spatial Scope. All of the firms had excess capacity of fixed inputs. These results support our hypothesis that fusion, alliance, and merger strategies followed by the principal European airlines after 1998 are not just explained by marketing strategies, but also by the cost structure of the industry.

Wiinteraction: a study on smart spaces interaction using the Wiimote

This paper describes a study on the use of the Wiimote as a generic interaction device for smart spaces. We have identified the range of interaction possibilities that can be explored when creating Wii-based interfaces for smart spaces and we have explored the application of those interactive features in the context of a typical museum guide. While there are many features that can be explored creatively to sustain the use of the Wiimote as a generic interaction device, we also found that there is at least one critical requirement that is not supported. More specifically, we have identified the need to include access to rich information, such as the one provided by digital displays. We thus propose a shared control mechanism for public displays that enables a user equipped with a Wiimote to first gain control and then browse information in a public display. The results of our study show no major limitation in the proposed approach, but identify device discovery as one major technical flaw that still needs to be overcome before the wiimotemay realistically become a generic interaction alternative for smart spaces

Modulation instability-induced fading in phase-sensitive optical time-domain reflectometry

Phase-sensitive optical time-domain reflectometry (?OTDR) is a simple and effective tool allowing the distributed monitoring of vibrations along single-mode fibers. We show in this Letter that modulation instability (MI) can induce a position-dependent signal fading in long-range ?OTDR over conventional optical fibers. This fading leads to a complete masking of the interference signal recorded at certain positions and therefore to a sensitivity loss at these positions. We illustrate this effect both theoretically and experimentally. While this effect is detrimental in the context of distributed vibration analysis using ?OTDR, we also believe that the technique provides a clear and insightful way to evidence the Fermi?Pasta?Ulam recurrence associated with the MI process

Comodificación y segregación socio-ambiental en Peñalolén: Comprendiendo su estructuración territorial

Analyzes and evaluates the expression of socio-environmental segregation in the town of Peñalolén, considering the district as a geographic scale that accounts for processes of exclusion in a context where the market has largely determined the present structure. In this regard, the distribution of socioeconomic groups shows that they are distributed in specific areas within Peñalolén and, on the other hand, indices of concentration and isolation alert regarding the configuration of zones that are concentrated and isolated for the same group , forming homogeneous sectors, unique and exclusive. Similarly, the distribution of vegetation cover shows a concentration of the highest rates in areas with concentrations of higher income groups. Thissituation reflects a process of commodification of the main factor of urban environment: vegetation. This process shows a deep connection with the recent urbanization of the community, driven by the installation of real estate projects that offer attractive conditions and used as environmental quality, consumer-oriented high-income, consolidating processes socio-spatial exclusion.Se analiza y evalúa la manifestación de la segregación socio-ambiental en la comuna de Peñalolén, considerando que corresponde a una escala geográfica que da cuenta de procesos de exclusión en un contexto donde el mercado ha determinado en gran medida su actual estructura. Al respecto, los grupos socioeconómicos se distribuyen en áreas específicas al interior de Peñalolén y, sus índices de concentración y aislamiento alertan respecto a la configuración de zonas homogéneas, exclusivas y excluyentes. De igual manera, la distribución de la cobertura vegetal muestra una concentración de los mayores porcentajes en los sectores donde se concentran los grupos de mayores ingresos, demostrando un proceso de comodificación de uno de los principales componentes del medioambiente urbano. La distribución espacial de los grupos sociales y la vegetación muestran una profunda relación con la urbanización reciente de la comuna, impulsada por la instalación de proyectos inmobiliarios que ofrecen y utilizan como atractivo condiciones ambientales de alta calidad, orientados a consumidores de altos ingresos, consolidando procesos de exclusión socio-espacial.  

Análisis Neoclásicos de Largo y de Corto Plazo Keynesianos de la Inversión en la Producción y el Crecimiento Económico de México

Examinamos los efectos de la inversión en la producción en el largo plazo neoclásico y en el corto keynesiano; se prueba la hipótesis nula de no causalidad de inversión y crecimiento en México, mediante una sola ecuación. Todos los estimadores sugieren una relación de cointegración entre la inversión y la producción. El largo plazo mostró inestabilidad a pesar de existir la relación de cointegración a través de pruebas de Chow y CUSUM, para corregirla, se empleó el método de Gregory-Hansen con un cambio estructural en 1984, sin embargo para obtener el modelo completo se incluyeron variables binarias en cuatro períodos, mostrando inestabilidad en el largo plazo de la economía mexicana. El modelo de corrección de error, muestra que la inversión constituye alrededor de un diez por ciento del peso bruto en la demanda agregada. Este peso es una fuente potencial de las fluctuaciones económicas de corto plazo.Inversión; Producción; Crecimiento Económico; México; Keynesiano; Neoclásico

Atribuição de informações orçamentárias em modelos de construção BIM

Orientador: Prof. Dr. Sergio ScheerDissertação (mestrado) - Universidade Federal do Paraná, Setor de Tecnologia, Programa de Pós-Graduação em Engenharia Civil. Defesa : Curitiba, 28/09/2021Inclui referênciasResumo: A presente pesquisa refere-se ao desenvolvimento de diretrizes para aprimorar o método de orçamentação de obra por meio de modelos BIM 5D. Uma pesquisa-ação foi adotada como procedimento, buscando aplicar dentro de uma construtora o procedimento proposto. Preliminarmente, uma revisão bibliográfica em conjunto com análises de documentos e observações diretas foram realizadas, visando identificar inconsistências na prática tradicional adotada pela Empresa. Em seguida, mediante observação participante, algoritmos foram desenvolvidos para automatizar o processo de orçamentação. As diretrizes criadas foram avaliadas por meio de uma aplicação direta em um empreendimento modelado em BIM 5D. Foram comparados os resultados obtidos por meio de planilhas orçamentárias obtidas no método tradicional de orçamentação e no procedimento proposto. A avaliação das diretrizes constatou aperfeiçoamentos na técnica orçamentária utilizada anteriormente pela construtora, observando reduções de aproximadamente 73% no tempo de execução de estimativas de custos e aumento na precisão dos orçamentos. Por intermédio das diretrizes propostas, este estudo pretende contribuir na discussão e desenvolvimento de técnicas que aprimorem a qualidade de orçamentos que utilizam o conceito BIM 5D.Abstract: This research refers to the development of guidelines to improve the cost estimation process through 5D BIM models. Action research was adopted as a method, searching to apply the proposed procedure within a construction company. Preliminarily, a bibliographic review together with document analysis and direct references was performed, identifying inconsistencies in the traditional practice adopted by the Company. Then, through participant observation, algorithms were developed to automate the estimation process. The general guidelines were evaluated through a direct application to a project modeled in 5D BIM. The results obtained through cost estimation spreadsheets in the traditional estimation method and the proposed procedure were compared. The evaluation of the guidelines found improvements in the budgeting technique previously used by the construction company, noting reductions of approximately 73% in the execution time of the process and an increase in the accuracy of the cost estimation. Through the proposed guidelines, this study intends to contribute to the discussion and development of techniques that improve the quality of cost estimations that uses the 5D BIM concept

Reabilitação da Igreja Velha de Tabuadelo

Dissertação de mestrado integrado em Arquitectura (área de especialização em Construção e Tecnologia)O trabalho de investigação e projeto proposto consistiu na reabilitação e requalificação do lugar da Igreja Velha de Tabuadelo. Neste projeto é proposta a realização de um percurso pedonal que liga o Centro de Freguesia de Tabuadelo à Igreja Velha e que vem complementar a proposta de uma série de programas lúdicos necessários para melhorar a qualidade de vida da população. Estes programas serão inseridos na transformação e reabilitação das edificações existentes e abandonadas no Lugar da Igreja Velha de Tabuadelo, com a inserção de ateliers, de um ginásio, um infantário e um centro de convívio para dinamizar e devolver identidade ao lugar. Neste trabalho é desenvolvido um Lar de Idosos, visto que ainda não existem estruturas de habitação específicas destinadas a pessoas desta faixa etária na freguesia. Assim se pretende, fundamentalmente, requalificar o lugar, e atrair pessoas para a sua ocupação através da proposta dos programas acima referidos, contribuindo para recuperar o seu valor e identidade.The research work and proposed project consisted in the rehabilitation and requalification of place of the Old Church of Tabuadelo. In this project, it was suggested the realization of a pedestrian path that connects the center of Tabuadelo’s parish to the Old Church and complements the proposal of a number of recreational programs needed to improve the quality of life of the population. These programs will be inserted in the transformation and rehabilitation of existing buildings and abandoned in place of the Old Church of Tabuadelo, with the inclusion of studios, a gym, a a kindergarten and a convivial center to energize and restore identity to the place. In this work, we developed a Sheltered Housing because there are still no specific housing structures intended for persons of this age group in the parish. Basically, the goal of this project is to retrain the place and attract people to its occupation by the proposal of the programs above mentioned in order to contribute to regain their value and identity

El uso de las construcciones de adverbio locativo con pronombre posesivo en el español peninsular : un primer acercamiento diatópico

This diatopic study examines the characteristics of the locative adverb constructions that select possessive pronouns as complements in Peninsular Spanish oral corpora. Firstly, the range of locative adverbs that take part in this construction are scrutinised, as well as their frequency of use with respect to that of their counterparts, in which a prepositional phrase appears as a complement to the locative adverb. Secondly, the geographic spread within Spain and the diatopic differences between the various autonomous communities are discussed. Thirdly, this paper also explores the variation in use between the possessive affixes -o and -a and the motivations traditionally given for this variation: to wit, the analogy with the final vowel of the locative adverb and the agreement with the referent of the possessive pronoun. Finally, it is proposed that diatopy, not previously considered in the literature, might be an influencing factor in said variation, given that there appears to be a strong link between the region and the use of one or another desinence of the possessive. This is, for instance, the case for Andalusia, where the vast majority of the locative adverb cases with possessives exhibit the suffix -a. En este estudio diatópico se documentan las características de las construcciones de adverbio locativo con pronombre posesivo en los corpus orales del español peninsular. Se listan los adverbios locativos que ocurren en estas construcciones, así como su frecuencia de uso respecto a la construcción con pronombre personal, es decir, la construcción alternante. Se evidencia, además, su difusión en el territorio español y se discuten las diferencias diatópicas en cuanto a la frecuencia de uso en las diferentes comunidades autónomas. De igual manera, se documenta la variación de los sufijos -o y -a de los posesivos que modifican a los adverbios locativos en España y se evalúan las motivaciones tradicionales de esta alternancia: la analogía con la vocal final del adverbio locativo y la concordancia con el referente del posesivo. Finalmente, se propone un factor adicional de esta alternancia, no identificado en estudios lingüísticos anteriores, la variedad diatópica, ya que se registra la existencia de una fuerte vinculación entre la región y el uso de una u otra desinencia del posesivo. Este es el caso de Andalucía, donde la gran mayoría de posesivos en estas construcciones adverbiales presentan el sufijo -a