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1.
Construction is commonly regarded as an important industry in economic policy making owing to its strong interactions with other sectors in the economy. Using six national input–output (IO) tables compiled to date and economic data for the period between 1969 and 2006, the behaviour of the Turkish construction sector and its relationships to investment, income and to other sectors in the economy are examined. Analysis reveals that the construction industry is losing its propulsive role and that it tends to exaggerate the fluctuations of the economy. The examination of lead and lag times between changes in GNP, construction activity and investments show that public sector spending cuts, in particular, have significant effects on the amplitude and the timing of slumps of the industry. The analysis of linkage indicators indicates that for the whole period under consideration the construction industry has high linkages with only one other industry. Thus the ‘leading’ role it plays in the economy is questioned.  相似文献   

2.
Nowadays, cultural activities are recognised as having a positive impact on regional and local development. In this paper, we analyse the economic impact of a new museum (the Gaudí Centre) on the regional economy by quantifying the amount of new productive income and new employment it has created. As far as we know, this is the first study to analyse the economic impact of a museum in quantitative terms by using an input–output subsystem analysis in which we differentiate the service sectors, which are closely connected to the museum’s direct demand, from the non-service activities, which are not so closely connected. Our results show that the museum has a considerable impact on the regional economy and suggest that cultural investments can play a role in income generation that goes beyond that of mere cultural activities.  相似文献   

3.
This study presents an integrated socioeconomic forecasting and analysis framework: a spatial regional econometric input?Coutput model and its application to the Chicago metropolitan area. The new framework is designed to overcome some limitations of existing models, particularly (1) limited consideration of population?Cemployment interactions and (2) dominance of top-down approach to vertical integration of regional and subregional variables. It captures local and lower level conditions and their effects on macroeconomic variables by using a modified disequilibrium adjustment model that incorporates subregional dynamics into a regional econometric input?Coutput model in a reciprocal, interactive manner, as opposed to a top-down allocation process. The framework also considers both region-wide and subregional level population?Cemployment interactions more systematically. It is demonstrated that the present model can support socioeconomic forecasting and a broad range of analyses, including the examinations of the macroeconomic impacts of local actions.  相似文献   

4.
The complexity and fragmentation of people's activity space are challenging to planners. However, the relevant studies are mostly concerned on the relationship between the social attributes and the activity space of residents in a single or several communities, or the spatiotemporal laws of activity space on a macro scale. The research on the spatial characteristics of residents' activity space still needs to be strengthened. The present study analyses the spatial patterns of residents' activity space based on mobile phone signaling data to fill the gap of previous studies that assessed residents' activity space across small geographic areas. First, according to the spatial scope and direction of an activity space and residents' activity coverage rate, spatial patterns can be divided into three types: compact, extended, and directional extension patterns. The CatBoost method is then used to statistically analyze the influencing variables of spatial patterns, and the order of importance of the following influencing factors is determined: the built environment is more influential than social and economic situations. This study aims to strengthen the understanding of residents' activity space at the spatial level and provide a basis for the optimization of communities with different spatial patterns.  相似文献   

5.
Limits on the precision of technical relationships within input–output frameworks have led to the use of stochastic analytical methods. The notion of stochastic analysis is developed in this paper to discern how the inherent imprecision effect, when aggregated data are utilised, affects the concomitant key sector analysis. Through a Monte Carlo based simulation, the stochastic key sector graph is introduced, with numerical expressions defined which quantify the association of the individual sectors to quadrants of the graph. The technical developments are benchmarked on a small problem, before a stochastic key sector analysis on an aggregated regional input–output table is reported. Comparisons are made between results when the aggregation of sectors is not employed. The paper reveals that aggregation in key sector analysis is inevitably a poor idea. However, it is argued that aggregation is often a practical necessity, so quantifying the uncertainty that is attendant on this aggregation is important, with the “association” expressions introduced potentially central to elucidate this uncertainty. The conclusions of this paper suggest that where analysts and decision makers are obliged to aggregate tables for analytical purposes then problems might be mitigated where marginal sectors are treated with care.  相似文献   

6.
The main purpose of this paper is to develop a new kind of input?Coutput multiplier that would be particularly well suited to quantifying the impacts of final demand changes on the sectoral output or value-added growth potential of an economy. Instead of using the traditional output multipliers, solving an appropriate optimization problem provides what can be called input?Coutput Euclidean distance multipliers. The method does not impose unitary final demand shocks with a fixed (predetermined) sectoral structure, thus allowing the economy to change across the spectrum of all possible final demand variations represented by vectors of modulus 1. It can be very helpful in measuring interindustry linkages and key sectors in a national or regional economy. An empirical illustration is made, using national (Spain and Portugal) and regional (Balearic Islands and the Azores) input?Coutput data.  相似文献   

7.
Developed countries in general, Spain in particular, have experienced a dramatic rise in the reception of foreign workers in the last decade. Among all the economic and social effects originated by the arrivals of immigrants, the literature has paid some attention to the potential effect that this immigration can produce on the internal migration patterns (the so-called “displacement effect”). This paper proposes the use of a multi-region input–output model of migrations for measuring how the reception of immigrants in one region displaces population among all the regions included in the model. From some basic assumptions, the input–output methodology proposed describes how the arrival of one immigrant in one region i, by the dissemination of internal population from i, generates indirect effects on other region j. To illustrate the methodology proposed in the paper, an empirical application for Spain is also included.  相似文献   

8.
Input–output analysis is a powerful tool for in-depth study of the productive structure of economic space. Moreover, the sectoral network constitutes one of the possible determinants of the innovative capacity of a territory. The use of network theory in the input–output field supposes an interesting alternative that allows structural complexity, weakness and strength to be shown. Following this viewpoint, we analyse the relative position of each sector via the structural holes concept (Burt in Structural Holes, Cambridge University Press, Cambridge, 1992; Social Capital: Theory and Research. Aldine de Gruyter, New York, 2001; Am J Sociol 110:349–399, 2004) to offer an approach to knowledge generation and diffusion capacity within the economic network. The theoretical background is based on the opportunities afforded due to connexion with and proximity to sectoral structure for knowledge transmission and consequently innovation capacity. This novel proposal is applied to the analysis of European and Spanish economies in 1995.  相似文献   

9.
A new type of steel–concrete composite beam that is specifically applicable to railway bridges is presented. The beam is featured with a channel shaped section. For such a section, the U-section steel beam is prefabricated with steel plates and the interior side of the channel is cast with concrete. The steel plates and concrete are integrated through shear stud connectors and work together to distribute loads. This type of structure not only inherits the characteristics of traditional concrete channel beams but also possesses its own unique attributes, such as advantageous mechanical performances, facilitating construction process, and low maintenance cost etc. To develop a design method for this new type of structures, and based on some FEM analysis, a static test of four-point symmetric bending was designed on a simply supported steel–concrete composite channel beam model with 1/3 sectional scale and 1/4 length scale. Preliminary research was conducted on its bending capacity, stiffness, stress distribution, crack diagram etc. Experimental results revealed that the steel plates and the concrete slab integrated through shear stud connectors can work well together and the channel beam model presented a bending failure mode. The flexural load carrying capacities and deformations of the composite channel beam were also analyzed by the Section analysis method, and the results agreed well with those from the test.  相似文献   

10.
Recent studies on ethnic entrepreneurship have pointed at an increasing share of migrants in urban small- and medium-sized entrepreneurial businesses. These migrant activities are crucial to the urban economy in many countries, as they employ a significant part of the workforce. The main objective of our study is to identify success conditions of ethnic entrepreneurship by using concepts from social capital and human capital from the literature on empirical factors that are responsible for successful ethnic entrepreneurship. The empirical part of the paper is based on a survey questionnaire among migrant entrepreneurs in the city of Amsterdam in the Netherlands and in Fairfax, County in the state of Virginia in the US. We present an overview of cultural, ethno-psychological and motivational aspects that contribute to the understanding of similarities and differences between ethnic entrepreneurs in both locations. The analysis is structured around several dimensions of social and human capital including personal and business characteristics, and network participation for improving business performance. The findings of the two studies are compared to explore a possible correspondence in business performance patterns. The research tool used to assess performance is Data Envelopment Analysis (DEA), a technique for comparative efficiency analysis in various types of corporate organizations. Finally, concluding remarks are presented and possible extensions of the analysis are suggested.  相似文献   

11.
We present a multidimensional generalization of the GRAS method (nD-GRAS) for the estimation of multiple matrices in an integrated framework. The potential applications of this method in regional and multi-regional input–output analyses based on national/regional accounts frameworks are many. We provide two real applications, a 3D-GRAS that estimates a use table at basic prices jointly with valuation matrices for Denmark; and a 4D-GRAS for estimating intercountry input–output tables with OECD data. We show that higher dimensional GRAS methods provide more consistent and accurate estimates than those with lower number of dimensions. We provide the analytical closed-form solution and the RAS-like algorithm for an easy operationalization.  相似文献   

12.
Previous research recognises the strategic role of vanguard projects in providing their initiators with avenues for entering new markets or gaining mastery over innovative technologies. This study makes a contribution to this research by focusing on the extent to which vanguard projects are under control and serve the interests of their principal initiators and the other actors involved. Simultaneously, the present study contributes to project management research by applying historical case study methodology on Eurocan, a vanguard project that a major Finnish forest industry firm Enso established in the mid-1960s to the wilderness of British Columbia, Canada. Our historical analysis encourages regarding vanguard projects as relay races in which several actors participate, largely in unanticipated ways. This is especially because the initiation of vanguard projects appears to be characterised by both the heterogeneity of the actors involved, a wide variety of actions taken by these actors to increase their centrality in the project organisation as well as abrupt changes among them and their relative importance over the project lifecycle. Together these characteristics make vanguard projects particularly prone to influence from external actors and events.  相似文献   

13.
Rockburst is one of the most difficult problems encountered in the pilot tunnels of the Jinping II hydropower station, where the rock cover is up to 2,500 m. Some typical characteristics of the rockburst events are summarized. These events indicate the intrinsic reason of rockburst is energy release. In order to understand the outburst mechanism, a new energy index, the Local Energy Release Rate (LERR), is put forward to simulate the conditions causing rockburst. By tracking the peak and trough values of elastic strain energy intensity before and after brittle failure, the LERR was developed to help understand rockburst from the viewpoint of energy release. To test its reliability, the brittle breakage of Mine-by tunnel rock in Canada and two rock bursts in the Jinping pilot tunnels were simulated. The results showed that LERR can satisfactorily predict the intensity of a rockburst and the depth of the outburst pit. Although it is not yet possible to determine thresholds at which rockbursts will occur, the study indicates the potential of LERR for evaluating rockbursts in deep underground excavations.  相似文献   

14.
In this paper the ability of a coupled BES–HAM model to reproduce realistic data is evaluated by comparing numerical results with measured data from a climatic chamber experiment. Calcium silicate plates are introduced into a test room and a small calcium silicate sample is installed in one of the walls. The response of the test room to relative humidity variations of the supply air is evaluated, while the supply air temperature is kept constant. The measurements confirm that due to the presence of hygroscopic materials in the test room, the relative humidity variations in the room are damped. The calculated temperature and relative humidity in the middle of the test room are well within the uncertainty interval of the measurements. On the other hand the coupled model predicts a larger damping and phase shift of the relative humidity variations inside the sample, yet the agreement between the calculated and the measured temperatures in the sample proves to be good. Finally, a sensitivity analysis is performed to evaluate the dependence of the numerical results on the uncertainty of the input parameters. It is demonstrated that by using a lower vapour resistance factor for the calcium silicate material, the agreement between the measured and calculated data is improved.  相似文献   

15.
Bulletin of Engineering Geology and the Environment - The microstructure of rock is one of the most important factors that affect its mechanical behaviors. In order to study the effects of grain...  相似文献   

16.
Structural measures, such as the commonly used open dam with a water–sediment separation function, are important in the mitigation of debris flow hazards and disasters. However, the existing open dams often lose their water–sediment separation function over time and/or during a debris flow event because of blockage by sediment and other debris. To resolve this problem, this paper describes a new debris flow water–sediment separation structure. This structure causes the separated sediment to leave the structure automatically and move to a deposit field. In this way, it maintains its water–sediment separation function in a debris flow event. To test the effectiveness of the new structure, model experiments were developed and tested in the laboratory. These showed that the water–sediment separation function was maintained. More than 80 % of the sediment larger than the design sediment was separated, and most of it left the structure automatically with the water–sediment separation functioning throughout the debris flow process.  相似文献   

17.
In this study we assess how higher education students (pre-service teachers) value and understand the impact of livestock production on global warming. We used a questionnaire with 91 students from a Portuguese institution and 111 from a Spanish one. The students had to mention measures to fight global warming, to explain the relationship between livestock production and global warming and to rank the impact of this cause compared to others. The Portuguese students showed a better understanding of this issue. Even so, the majority of the students do not recognize the high impact of livestock on global warming and consider other causes more relevant.  相似文献   

18.
Different concepts for modelling of soil-foundation in complete dynamic interaction analysis for a 110-m height 70-m span arched structure on 180 piles were investigated in this paper. The modelling approaches consisted of a sophisticated procedure to account for soil compliance and foundation flexibility by defining frequency-dependent springs and dashpots; namely, flexible-impedance base model. The results of this model were compared with those of the conventional modelling procedures; namely, fixed base model and flexible base model by defining frequency-independent springs. In the flexible-impedance base model, the substructure approach was employed through finite element modelling. To account for the kinematic interaction, the numerical model of the soil, foundation and piles were developed using a verified finite element model in ABAQUS. The free field time history and design spectrum were modified to obtain the foundation input motion. The impedance of pile groups with different length was obtained by the finite element model to assess the inertial interaction. The comparison of the results of the employed models showed that rocking and torsional responses were greatly affected by soil–structure interaction, indicating redistribution of seismic demands. It was also proven that the internal demands of the conventional model considering frequency-independent Winkler springs might be higher than those of the model including pile–soil–structure interaction effects.  相似文献   

19.
This paper estimates the parameters of the wage equation of the new economic geography (NEG) using a newly developed spatial panel model. The results show that wage rate variation across different prefectures in Japan can be explained by market potential, which is a key variable in NEG theory, while controlling for variation in labour efficiency. Spatial heterogeneity is particularly important in the context of Japan in part because of its complex physical geography and the spatial distribution of its principal urban centres. The paper considers the challenges associated with representing the spatial relationships between prefectures describing and implementing different approaches to measuring transport costs.  相似文献   

20.
This study reported an actual building fire incidence for a ten-story building that occurred in Taiwan in 2008. Due to the stack effects the fire occurred on the third floor spread through the patio in a short time to the upper floors and caused three deaths in a tenth floor apartment. This study also attempted to reconstruct the actual fire scenario using computer simulation. The spread of the fire to the combustibles due to hot smoke was accounted for in the simulation. Variation of the fire scenario and the factors causing the fire spread were studied. It was found that an initial fire size below 1.0 MW would not generate sufficient hot smoke to cause fire spread despite the stack effects. However, any obstructions in the patio such as window shading has been found to cause heat accumulation that would aggravate the fire spread problem. The presence of a canopy at the top of the patio can cause higher concentration of smoke for the upper floors. The simulation results are found to be in good agreement with the actual incidence. Moreover the simulation results also show that when the fire spread through the patio the initial fire size of 1.0 MW at the fire site can grow to a building fire of 300 MW.  相似文献   

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