Search results for "agglomeration"
showing 10 items of 88 documents
Estimating Verdoorn law for Italian firms and regions
2011
In empirical regional economics, returns to scale are typically estimated at the regional level in search for evidence on alternative theories of growth and agglomeration. However, returns to scale may also have a firm-level dimension. In this paper, we exploit micro level data and estimate the dynamic Verdoorn law in a multilevel-setting, where returns to scale are obtained simultaneously for the micro and the regional level. Using Italian firm-level data and the NUTS-3 level of aggregation, we estimate the classic and augmented versions of Verdoorn law for the manufacturing sector, and the rest of the economy for comparison. Our results show that increasing returns to scale co-exist at bo…
Welfare, Home Market Effects, and Horizontal Foreign Direct Investment
2005
We investigate the spatial distribution and organization of an imperfectly competitive industry when firms may choose to operate more than a single production unit. Focusing on a short-run setting with a fixed mass of firms, we fully characterize the spatial equilibria analytically. Comparing the equilibrium and the first-best, we show that both organizational and spatial inefficiencies may arise. In particular, when fixed costs are low enough the market outcome may well lead to overinvestment and, therefore, to too many multinationals operating from a social point of view. Furthermore, once multinationals are taken into account, the market outcome may well lead too little agglomeration.
Regional Inequality and Product Variety
2005
We investigate how differences in set-up costs of various types affect the trade-off between global efficiency and spatial equity and show that the standard assumption of symmetry in fixed costs masks the existence of an interesting effect: the range of available varieties varies depends on the spatial distribution of firms. In such a setting, even when the market outcome leads to excessive agglomeration under symmetric fixed costs, a planner opts for asymmetric fixed costs and more agglomeration. The reason is that the losses induced by more agglomeration are offset by the gains due to additional product variety.
Agglomeration and dispersion of economic activities in and around Paris: An exploratory spatial data analysis
2010
The agglomeration patterns of twenty-six manufacturing and service sectors in and around Paris in 1999 are analysed. The method used measures the intensity of spatial agglomeration and identifies the location patterns of economic sectors. First the locational Gini coefficient and Moran’s I statistics of global spatial autocorrelation are computed. These provide different but complementary information about the spatial agglomeration of the sectors under study. Then exploratory spatial data analysis tools are applied. Moran scatterplots and local indicators of spatial association statistics reveal great diversity in location patterns across sectors.
Modéliser la suburbanisation
2002
L’histoire de la suburbanisation de la population et de l’emploi, principalement aux Etats-Unis, permet d’identifier trois caracteristiques du phenomene. 1/ La suburbanisation se traduit par un etalement urbain tel que population et emploi s’accroissent plus en peripherie qu’au centre. 2/ La suburbanisation fait emerger de nouvelles concentrations d’activites dans la peripherie des villes-centres et donne naissance a des structures urbaines multicentriques. 3/ La suburbanisation differencie les contenus et les fonctions economiques des centres et recompose les centralites urbaines. Dans ce cadre, la suburbanisation se presente selon des modalites differentes selon les epoques et les regions…
Evaluation of advanced silica packings for the separation of biopolymers by high-performance liquid chromatography
1984
Abstract In the separation of proteins and peptides by the various modes of high-performance liquid chromatography, the nature of the substrates requires the use of microparticulate silica packings with bonded ligands of appropriate design. Agglomeration of monodisperse silica hydrosols of defined size distribution into beaded particles provides a useful method of controlling the pore size, the size distribution, the particle porosity and surface area of these packings. The particle porosity is shown to be a major factor governing the packing density and packing stability of the column. For size-exclusion chromatography of proteins, parent silicas of pore size 10 and 100 nm with a narrow po…
Vacancies and Carbon Impurities in Iron
1981
Point defects in electron-irradiated high-purity α-iron have been studied by positron lifetime measurements. We show that the migration stage of monovacancies occurs already as low as at 220 K, which results in agglomeration of small three-dimensional vacancy clusters. Furthermore, we irradiated carbon-doped iron specimens, where formation of highly asymmetric monovacancycarbon atom pairs was detected during the migration stage of monovacancies at 220 K.
Synthesis of Nanoferroics
2013
The Chapter covers the technological aspects of many chemical and physico-chemical nanofabrication methods relevant to making nanoferroic materials and composites. First, the classification of relevant synthesis methods of nanoferroics has been presented. Synthesis of particular nanoferroics with different chemical bonding like metallic, oxide and non-oxide compounds is considered in details. Among the methods, the mechanochemical, sonochemical, hydrothermal, co-precipitation, emulsion, thermal decomposition of unstable precursors have been analyzed. The competition between new phase nucleation and nuclei growth has been revealed to be controlled using feedback between reaction rate and tem…
Misure di agglomerazione spaziale nei Sistemi Locali del Lavoro siciliani
2009
Spatial agglomeration indicators in the Sicilian Local Labour Systems Objectives - This paper examines the links among productive specialization, variety of the economic environment and knowledge spillovers on the basis of the territorial analyses present in the current literature. With the aim of identifying localization benefits in a particular area, some aspects of business settling are compared with trends in the development of economic activities and, particularly, with agglomeration process of the firms. Methods and Results The empirical analysis will be carried out pointing to the dynamics of employment consequent to the effects of the externalities above mentioned. Employment data a…
Enabling Multimodal Interaction in XPL – the eXtensible Presentation Language
2007
This paper introduces the multimodal extension of the eXtensible Presentation architecture and Language (XPL), a framework aimed at streamlining multi-channel interface design process and enabling full component reuse. XPL incorporates a presentation language based on design pattern paradigm, which supplies a clear distinction between the presentation layer and the corresponding programming logic, promoting contents aggregation and a variety of event handlers described without relying on a (procedural) scripting language. In this paper, the design pattern concept is extended to voice-based interaction, and two verbal design pattern (VeDP) are introduced along to their visual counterparts. T…