Economic growth in Italian NUTS 3 provinces

This paper analyzes the conditional \(\beta \) -convergence hypothesis for NUTS 3 Italian provinces. A methodology for the simultaneous treatment of spatial dependence and spatial heterogeneity is developed. Spatial dependence is introduced in the economic model by assuming a spatial Durbin model specification. The absence of data experienced by some economic variables at the NUTS 3 level is addressed through a modified version of the Bayesian interpolation method introduced by Palma and Benedetti (J Geogr Syst 5:199–220, 1998). Spatial heterogeneity is taken into account by identifying convergence clubs. For this purpose, we use the modified simulated annealing algorithm introduced by Postiglione et al. (Comput Econ 42:151–174, 2013). The methodology is compared with the heteroscedastic approach proposed by Kelejian and Prucha (J Econom 157:53–67, 2010).     

The export-base model with a supply-side stimulus to the export sector

In the export-base model, the level of a region??s economic activity is underpinned by the performance of its export sector (Daly in Econ J 50:248?C258, 1940; Dixon and Thirlwall in Oxf Econ Pap 27:201?C214, 1975; Kaldor in Scott J Polit Econ 17:337?C348, 1970; North in J Polit Econ 63:243?C258, 1955). This theory is now almost universally represented as a primitive version of the familiar Input?COutput or Keynesian demand-driven approach, where regional output is linked to regional exports through a rather mechanistic multiplier process (Romanoff in J Reg Sci 14:121?C129, 1974). Further, in a standard IO inter-regional framework, the expansion of output in one region always generates positive impacts on other regions. That is to say, there is always a positive spread, and no negative backwash, effect. However, these models typically embody no supply-side constraints. What is more, the stimulus to the export sector is often thought to come through supply-side improvements (North in J Polit Econ 63:243?C258, 1955; McCombie in Appl Econ 24:493?C512, 1992). Whilst accepting that the development of a healthy export base is generally central to promoting the growth of the regional economy, the relationship is likely to be much more complex than is usually thought. Also whilst an increase in regional exports typically increases economic activity in the target region, the effect on other regions is less straightforward (Myrdal in Economic theory and underdeveloped regions Duckworth, London, 1957). In this paper, we begin by using a single-region IO analysis of the operation of a stylised export-base model. The impact of a conventional increase in export demand is compared to a situation in which increased competitiveness underpins the improved export performance. This analysis is then extended through the use of an inter-regional (Scotland?CRest of the UK) Computable General Equilibrium (CGE) model. In simulation, different exogenous demand and supply side disturbances are calibrated so as to generate the same long-run expansion in Scottish manufacturing exports. The subsequent specific evolutions of regional GDP and employment in both Scotland and the rest of the UK (RUK) are then tracked.     

Caractérisation minéralogique et géotechnique des argiles marneuses gonflantes de la région de Médéa,Algérie

This paper presents the approach followed for the geological, mineralogical, and geotechnical characterization of swelling marly clays in the Médéa region. This investigation is conducted in order to estimate the swelling potential of this marly clay layer. The studied sites, located at about 80 km south of Algiers, Algeria, cover an area of approximatively 400 hectares. Five sites are considered. In the first step, the geological, tectonic, climatic, and hydrological contexts of the region are described. According to the geological map of Médéa, most of the formations encountered in the area are composed of Miocene layers represented by marly clays (Fig. 2). This region is characterized by its high and low temperature in summer and winter, respectively, and variable humidity (Fig. 3). In a second step, the results of geotechnical studies, X-ray diffraction tests, chemical analyses, and scanning electron microscope (SEM) observations are presented (Figs. 3, 4, 5, 6, 7, 8, 9). The soils contain quartz (20–26 %), calcium carbonates (11–55 %), kaolinite (8–13 %), illite (6–14 %) and Montmorillonite (18–26 %). The study of their microstructure by means of SEM indicates that these soils are formed by a compact marly clay matrix that is relatively homogeneous and oriented in the dip direction of bedding. A grain size analysis shows that the clay content varies between 17 and 70 %. The water content of all samples varies between 8 and 30 %. The values of the liquidity limit (LL) and plasticity index (PI) vary between 28–76 % and 16–36 % respectively, indicating a highly plastic soil; this is also confirmed by a specific surface varying between 99 and 179 m²/g. The dry density γ _d varies between 15 and 19 kN/m³. The swelling potential of the marly clay samples is evaluated firstly using various indirect methods. In literature, a number of empirical classifications are proposed by different authors (BRE 1980; Chen 1988; Komornik and David 1969; Seed et al. 1962; Snethen 1984; Vijayvergiya et Ghazzaly 1973 et Williams and Donaldson 1980). The swelling potential is related to certain physical properties of soils, such as consistency limits, clay content, methylene blue value, etc. In general, these methods indicate that all the tested soils have a high swelling potential, which confirms the results of mineralogical analysis. Secondly, direct measurements of swelling parameters are performed. Swelling tests are carried out using a standard slaved one-dimensional odometer using two methods: free swell and constant volume, according to standard ASTM D 4546-90 and AFNOR (1995). The swell pressure, the swell percentage and the swell index are given in Fig. 16. It is noted that the soils develop very significant swell pressures which vary between 25 and 900 kPa. This is in agreement with the results obtained by empirical methods. This investigation clearly shows that the marly clays of the Médéa region have a high swelling potential. Therefore, taking into account the phenomenon of soil swelling in structure design is essential.     

Hotelling was right with decreasing returns to scale and a coalition-proof refinement

This paper provides a simple, realistic, and very slightly modified version of the production technology in Hotelling’s (Econ J 39:41–57, 1929) spatial model with linear transportation costs to overcome the nonexistence problem of equilibrium—decreasing returns to scale. It is shown that a pure strategy Nash equilibrium in price competition always exists for all location pairs and guarantees uniqueness if we utilize a coalition-proof refinement introduced by Bernheim et al. (J Econ Theory 42:1–12, 1987). Decreasing returns to scale reduce the profit a firm can capture through price undercutting and stabilize the price equilibrium due to the increasing average production cost of firms. As a consequence, duopoly firms agglomerating at the center of a line are shown to be at the unique location equilibrium. This paper confers a new validity to the so-called principle of minimum differentiation, in some sense, with the least deviation from the original Hotelling (Econ J 39:41–57, 1929) model.     

Uncertainty in Estimating the Fire Control Effectiveness of Sprinklers from New Zealand Fire Incident Reports

The current state of fire sprinkler effectiveness information has been found to be a limiting factor when comparing the fire risk for alternative building designs in New Zealand (Determination 2005/109: single means of escape from a high-rise apartment building. Department of Building and Housing, Wellington, 7). Data on the past performance of systems in real fires is one of the best sources of information to estimate future performance, but there has not been a detailed study on sprinkler effectiveness data from fire incidents in New Zealand published since Marryatt’s work (Fire: a century of automatic sprinkler protection-revised. Australian Fire Protection Association, Melbourne, 13), which was last updated in 1986 and included data from Australia. The current research looks at the quality and quantity of data available on sprinkler effectiveness from New Zealand Fire Service (NZFS) incident reports over the period of 2001 to 2010 to evaluate the data’s usefulness for risk-informed building fire safety design. A comparison is made between the number of sprinklers reported activated in the NZFS dataset, Marryatt’s study, guidance from PD 7974-7:2003 (PD 7974-7:2003: the application of fire safety engineering principles to fire safety design of buildings. Probabilistic Risk Assessment, London, 3), and NFPA data (U.S. experience with sprinklers and other automatic fire extinguishing equipment. National Fire Protection Association, Quincy, 12). Proposals to improve the collection and reporting process to increase the informative value of future NZFS data for risk-informed fire safety design are presented.     

Spatial competition with quadratic transport costs and one online firm

d’Aspremont (Econometrica 47:1145–1150 , 1979) showed that a Hotelling (Econ J 39:41–57 , 1929) duopoly model with quadratic transport costs yields maximal differentiation. However, the introducing of an online firm ensures that the duopolist will never be located at the end points of the market. In other words, an online firm can raise a market effect that induces two firms to be finitely differentiated. The implication of the socially optimal solution is derived. The results herein can be extended to allow multiple firms. Finally, a free-entry equilibrium and the Stackelberg equilibrium are also discussed.     

A note on the null distribution of the local spatial heteroscedasticity (LOSH) statistic

Recently, Ord and Getis (Ann Reg Sci 48:529–539, 2012) developed a local statistic \(H_i\) , called local spatial heteroscedasticity statistic, to identify boundaries of clusters and to describe the nature of heteroscedasticity within clusters. Furthermore, in order to implement the hypothesis testing, Ord and Getis suggested a chi-square approximation method to approximate the null distribution of \(H_i\) , but they said that the validity of the chi-square approximation remains to be investigated and some other approximation methods are still worthy of being developed. Motivated by this suggestion, we propose in this paper a bootstrap procedure to approximate the null distribution of \(H_i\) and conduct some simulation to empirically assess the validity of the bootstrap and chi-square methods. The results demonstrate that the bootstrap method can provide a more accurate approximation than the chi-square method at the cost of more computation time. Moreover, the power of \(H_i\) in identifying boundaries of clusters is empirically examined using the proposed bootstrap method to compute \(p\)  values of the tests, and the multiple comparison issue is also discussed.     

Evaluation of cementation of Jeju coastal sediments using in situ tests

A series of SPT, CPT and SPS tests were performed for Jeju coastal sediments in order to investigate the possibility of detecting the cementation of granular sediments by in situ tests. Plotting the in situ test results into the G_max/q_c–q_c1 and (G_max/p_a)/N₆₀–(N₁)₆₀ relations suggested by Schnaid et al. (Proceedings of 1st international conference on site characterization, Balkema Pub, Rotterdam 2004) indicates that the Jeju calcareous sediments are cemented. It is also observed that the q_c/N ratio of Jeju sediments is much higher than the (q_c/p_a)/N₆₀–D₅₀ relation suggested by Kulhawy and Mayne (Manual on estimating soil properties for foundation design, EPRI, Ithaca 1990). It is suggested a relative density?>100?% obtained using the q_c–D_R–σ_v′ relation suggested for uncemented sands indicates cementation of the in situ sediments. The G_max/q_c value of Jeju sediments was found to be 2–6 times larger than that of uncemented sands at the same normalized cone resistance. It is concluded that in situ penetration resistances are relatively insensitive to the cementation of granular soil while the deformation moduli are significantly affected by the cementation, and that the relative density and G_max of cemented sediments can be seriously misjudged unless the effect of cementation on in situ penetration test results is considered.     

Are small communities at risk of population loss?

Small communities almost universally worry about out-migration and the negative effects of out-migration on community viability. Using Oregon community-level data and applying the threshold estimation method of Hansen (Econometrica 68(3):575–603, 2000), we are able to identify population thresholds that distinguish small communities from their larger counterparts based on significant structural differences in factors affecting net migration. Our results suggest that smaller communities are more at risk of population decline than larger ones. After controlling for spatial spillovers from neighboring communities, the average net migration rate is 3 % in the larger communities (roughly above 5,000 population), 2 % in the mid-sized communities (roughly between 1,250 and 5,000) and $-3$  % in the smallest communities (roughly less than 1,250). Other things equal, geographic isolation from large cities and low wage rates provide some protection from net out-migration for the smallest communities, but even for the smallest places, a larger population base lowers the risk of net out-migration.     

A note on convergence across Canadian provinces: new insights from the club clustering algorithm

This paper employs the newly-developed convergence tests introduced by Phillips and Sul (Econometrica 75:1771–1855, 2007) to investigate convergence of real GDP per capita across Canadian provinces, as well as the transitional path of factors behind the convergence or divergence pattern. In contrast with previously published studies on Canadian provincial convergence, the analysis carried out in this paper allows for heterogeneous technology and reveals that Canadian provinces are characterized by distinct convergent clubs, that is, separate convergence clubs that converge to different steady states. We make the case that the findings presented in this paper are of utmost importance for Canadian policy-makers as they seek to develop effective policy measures to address regional economic disparities.     

Erosion d’une vase de l’estuaire de la Loire sous l’action du courant

This research work deals with an experimental study on the erosion phenomenon of a mud under the action of a water current. It is observed from research works carried out by Partheniades (J Hydraul Div ASCE 91(HY1):105–139, 1965), Migniot (La Houille Blanche 1&2:11–29, 95–111, 1989), Ockenden and Delo (GeoMar Lett 11:138–142, 1991), Aberle et al. (Mar Geol 207:83–93, 2004), among others, that mud erosion process by an hydrodynamic action depends mainly on sediment properties. Based on a literature study, this critical stress is assumed to be proportional either to the effective cohesion (Eq. 2) or to the yield stress (Eq. 4) of the sediment bed. Six erosion test series have been performed at six different concentrations of a mud from the Loire estuary. Some properties of the tested sediments are: a solid particles density ρ _s = 2,550 kg m^?3, a liquidity and plasticity limit at 140 and 70% of the water content, respectively, a mean size of the dispersed mineral fraction determined by laser techniques of 10 μm, and a volatile matters content of 11.86% by total dry weight burned at 550°C. As the rheological behaviour is difficult to describe, the sediment strength is characterized by only a parameter, namely, the yield stress τ _y . It is measured with a coaxial cylinder Brookfield LVT viscosimeter following a defined procedure (Hosseini in Liaison entre la rigidité initiale et la cohésion non drainée dans les vases molles—Relation avec la dynamique sédimentaire. Thèse, Université de Nantes, 167 p, 1999). For each studied concentration, three successive erosion tests are carried out, and for every erosion test, 15 successive measurements of τ _y are made. The mean values and the standard deviations of τ _y are shown in Table 1 as a function of the bed sediment concentration C. A confined flume has been conceived and built to characterize the erosion rates. With this device, a current-induced shear stress is generated above an homogeneous deposited sediment (Fig. 1). The bed shear stress τ _o is calculated from the measured mean velocity V by Eq. 5. The friction coefficient c _f involved in Eq. 5 has been evaluated from measurements of the hydraulic pressure loss. Finally, the validity of Eq. 5 has been confirmed by five calibration tests on the incipient of the movement of sands for which results are compared with Shields diagram in Fig. 2. The observed erosion mechanisms affecting cohesive sediments depend mainly on the value of the yield stress. For a fluid mud (τ _y less than 3 N m^?2), the bed shear stress produces at first a wavy motion on the bed surface with a progressive undulation. When the shear stress increases, resuspension produces a diluted sediment cloud which is entrained and dispersed by the flow. For a plastic mud (τ _y greater than 3 N m^?2), erosion occurs by a wrenching of aggregates which are transported near the bottom. Initially, the eroded aggregates measure several millimetres in size; but, once transported, aggregates break into very rigid and compact aggregates of maximum size close to 1 mm in all the cases. During erosion tests, erosion volumetric rates E _v have been evaluated under steady-state bed shear stress τ _o from the observed variation in time of suspended sediment concentration. A generalized erosion is assumed for E _v ≥ E _vo = 3 × 10^?7 m s^?1 (that is the equivalent of 1 mm sediment layer eroded per hour). The generalized erosion occurs above a critical bed shear stress τ _oe which is linked to τ _y and mud density through Eq. 7. A phenomenological law defined by Eq. 8 is proposed to calculate the erosion rate as a function of yield stress and hydrodynamic shear stress at the bottom. For τ _o < τ _oe , a small erosion is observed, which is described by a formulation given by Cerco et al. (Water quality model of Florida Bay. U.S. Army Engineer Research and Development Center, ERDC/EL TR?00-10, Vicksburg, USA, 260 p, 2000). Above τ _oe , a small increase in τ _o produces an important erosion rate rise which is described by a formulation suggested by Mehta and Partheniades (Resuspension of deposited cohesive sediment beds. In: Proceedings of the 18th coastal engineering conference, Cape Town, South Africa, 2:1569–1588, 1982). Figure 3 shows as a function of τ _o the observed values of E _v (discrete symbols) as well as the proposed model (in solid lines) for the six concentrations. For the theoretically maximum value of E _v , the hydrodynamic shear stress is very high with regard to the sediment cohesion; and then, the water flux produces an entrainment of underlying fluid mud layers. The asymptotic law obtained from the model of Kranenburg and Winterwerp (1997) plotted in dashed lines in Fig. 3, is expressed by E _v = 0.3 u _* . A sediment trap inserted in the experimental system allows a sample of eroded mud aggregates to be obtained. It is observed that the maximum value of the diameter D _M of the eroded aggregates depends on the density and yield stress of the initially deposited mud according to Eq. 10. In the same way, the density of the aggregates issued from plastic mud erosion is measured following an original experimental method and procedure (Table 3). The erosion of plastic muds with a concentration from 310 to 420 kg m^?3 produces aggregates with a concentration close to 400 kg m^?3 and yield stress a little greater than 100 N m^?2.     

Determinants of cross-regional R&D collaboration: some empirical evidence from Europe in biotechnology

In this study, we focus on the pattern of cross-regional R&D collaborations through which voluntary knowledge flows and accompanying spillovers might occur. Our aim is to investigate the processes that give rise to the observed network configuration in order to identify hampering factors of knowledge diffusion, with a particular interest in the role of geographical proximity and differences in territorial features. We make use of the data on project proposals submitted to the 7th Framework Programme in the field of biotechnology. We build a non-valued inter-regional R&D cooperation network among a set of European regions and study its formation through exponential random graph models (Frank and Strauss in J Am Stat Assoc 81(395):832–842, 1986; Wasserman and Pattison in Psychometrika 61(3):401–425, 1996). Besides the role played by absorptive capacities, the empirical results reveal that contiguity affects the pattern of cross-regional collaborations not only via edge formation among neighbours but also through a triadic closure process which links neighbouring regions to non-neighbours. Furthermore, triadic closure is found out to be in play among highly populated regions and regions including capital cities.     

“We Are Good at Surviving”: Street Hustling in Addis Ababa's Inner City

Recent studies of the informal economy have tried to understand how the politics of informal actors and their attempts at organizing themselves have created new collective platforms for social practice and social action in the African city (Lindell Africa's informal workers. Collective agency, alliances and transnational organizing in urban Africa (pp. 1?C33) 2010; Meagher African Studies Review 54(2):47?C72, 2011). These studies have suggested that the informal is not only the domain of the poor and their form of solidarity but also a terrain where new powerful actors in and outside the city might emerge and where power dynamics and forms of differentiation are at work. With a similar theoretical concern, this paper focuses on how engagement with the ??street economy?? among men between their mid-20s and mid-30s in Addis Ababa's inner city reveals broader experiences of exclusion and marginalization.     

“Third places” and social interaction in deprived neighbourhoods in Great Britain

This paper explores social interaction in local ‘public’ social spaces such as local shops, pubs, cafés, and community centres in deprived neighbourhoods. More specifically, it examines the importance, role and function of these places, which have been described by Oldenberg and Brissett (Qual Sociol 5(4):265–284, 1982), Oldenburg (Urban design reader. Architectural Place, Oxford, 2007) as being “third places” of social interaction after the home (first) and workplace (second). It does so by drawing on data gleaned from in-depth interviews with 180 residents in six deprived areas neighbourhoods across Great Britain, conducted as part of a study of the links between poverty and place funded by the Joseph Rowntree Foundation. The paper notes that local third places are an important medium for social interaction in these areas, although their importance appears to vary by population group. It notes that shops appear to be a particularly important social space. It also identifies some of the barriers to social interaction within third places and concludes by highlighting some of the key implications for policy to emerge from the research.     

County-level determinants of local public services in Appalachia: a multivariate spatial autoregressive model approach

We develop a multivariate spatial autoregressive model of local public expenditure determination based on the maximization of a strictly quasi-concave community utility function. The existence of spatial interdependence is tested for both the spatial error and spatial lag model. The full model is estimated by efficient GMM following Kelejian and Prucha (J Real Estate Finan Econ 17(1):99?C121, 1998). The results indicate significant spillover effects among local governments with respect to spending on public services. The OLS estimates of the conventional (non-spatial) model and the corresponding maximum likelihood estimates of the spatial lag and the spatial error models are presented for comparison purposes. The GMM estimates are found to be more efficient.     

Spatial price discrimination and location choice with labor markets

This paper generalizes Hwang and Mai’s (Am Econ Rev 80:567–575, 1990) model to include labor markets and shows that their results are still valid when the difference of inverse demand slopes is large enough, while, when this difference is small, a monopoly firm always chooses the same (boundary) location under different pricing scenarios. In the latter situation, total outputs are identical in different pricing scenarios, while the social welfare under discriminatory pricing is definitely less than that of the mill pricing. Our results are robust, no matter whether the commuting costs are paid by the firm or workers, and no matter whether wages are discriminatory or uniform.     

Systematic review: an analysis model for measuring the coopetitive performance in horizontal cooperation networks mapping the critical success factors and their variables

Several strategies have been developed for micro-enterprises and small enterprises in relation to their competitiveness enhancement. In recent years, one of the most widespread strategies has been the formation of horizontal cooperation networks (HCNs), based on the evolutionary development of coopetition. This study aimed to support and validates an analysis model developed by Petter (Modelo para análise da competitividade de redes de cooperação horizontais de empresas, Universidade Tecnológica Federal do Paraná, UTFPR, Ponta Grossa, 2012), in order to point out which are critical success factors (CSF), and their variables which influence the coopetition performance of a HCN under aspects of cooperation and competitiveness. A systematic review supported by Sampaio and Mancini (Revista Brasileira de Fisioterapia 11(1):83–89, 2007) was used to measure the status quo of published journals related to the subject, among several databases. A large informational gap was found concerning the development of methods and tools, as well as subsidies. Regarding the raise of publications found inside the scope, 18 CSF, 52 variables were mapped correlating them with 144 indicators, therefore, supporting and validating the proposed model of analysis.     

Modifications to the GSI for granite in drilling

The Geological Strength Index (GSI) is widely used to estimate mechanical parameters of rock mass, but estimation of GSI is relatively subjective because of the lack of quantitative parameters. Hence, the existing method for estimating GSI is not suitable for rock samples from drilled cores. Inspired by the GSI estimation method of flysch (Marinos and Hoke, Proceedings of the GeoEng2000 at the international conference on geotechnical and geological engineering, Melbourne, Technomic publishers, Lancaster, pp 1422–1446, 2000), this paper proposes two parameters, the rock mineral condition and rock core length, for use in a modified, more quantitative method for estimating GSI. This modified method can be used for granite specimens from drilled cores. It uses images of typical core samples instead of the sketches given by Hoek’s GSI estimation method. A modified chart of GSI for granite, which is suitable for estimating mechanical parameters of rock mass from drilled core samples, is then developed. The E (elastic modulus) and Q _ult (ultimate bearing capacity) values obtained using our modified method were compared with those from experimental data; the results indicate that the modified method can produce reasonable GSI values and can be used to estimate the mechanical parameters of rock mass from drilled cores.     

浅埋大跨洞桩隧道变形监测与控制分析

针对采用洞桩法施工的北京地铁10号线工体北路站,介绍了浅埋大跨洞桩隧道的变形监测与控制措施。根据监测数据,对洞桩法隧道导洞开挖,主体扣拱的拱顶沉降与洞周收敛以及地表和上部立交桥基础的沉降变形规律进行了分析研究。结果表明：1)采用洞桩施工方法能有效控制浅埋大跨隧道地表沉降和地层变形;2)隧道埋深和跨度、导洞开挖对浅埋大跨洞桩隧道变形影响显著;3)设置超前小导管注浆,及时施作初期支护和二衬,可以有效的控制变形的发展。     

Critical perspectives on network governance in urban regeneration, community involvement and integration

Significant claims have been made about the benefits of network governance and management in securing community involvement and assisting social integration in complex urban regeneration programmes. The move from vertical to horizontal forms of coordination, and the assumption of a more equal power distribution between participants, have combined with an emphasis on mutuality and trust to present networks as a promising mechanism for pluriform involvement and collective decision-making. Often this promise runs ahead of the evidence of how network governance functions in practice, the opportunities for different actors to influence the process and the often disappointing outcomes of joint decision-making. This special issue contributes to the ‘second generation of research on governance networks’ by tackling key questions relating to the sources of governance network failure and success. Building on the articles in this special issue, we explore these questions in relation to urban regeneration, community involvement and the integration of minority groups in The Netherlands, Sweden and England. This article reviews the articles in this special issue from the perspective of Klijn and Skelcher’s (2007) four conjectures on democracy and governance networks and Sørensen and Torfing’s (2007) four conditions for democratic anchorage. It also suggests ways in which the research agenda on networks in urban regeneration, community involvement and integration might be developed.