Search results for "table"
showing 10 items of 2807 documents
Aggregation in Input–Output Tables: How to Select the Best Cluster Linkage
1991
In this paper we try to give a solution to the aggregation problem on working with Input–Output tables. First of all we verify the degree of similarity among the production functions of the industries which aggregate in each sector. Secondly, once we have established the aggregation by using different cluster analysis, we set a number of conditions required to choose the proper linkage method that allows us to characterize the process of aggregation (weighted or unweighted) of the input–output table.
Understanding the shortcomings of commodity-based technology in input-output models: an economic-circuit approach
2004
International audience; The Make-Use Model serves as a basis for most national accounting systems as the System of National Accounts (SNA) and is acknowledged as the most suitable model for interregional analysis. Two hypotheses are traditionally made featuring either industry-based technologies (IBT) or commodity-based technologies (CBT). While industry-based technologies can be easily interpreted in terms of a demand-driven economic circuit, it will be shown that: (1) commodity-based technologies cannot be interpreted as a demand-driven economic circuit because this involves computing the inverse of a matrix (the matrix of industry output proportions), which is either impossible or genera…
"A Comment on Tobias Kronenberg's "Construction of Regional Input-Output Tables Using Nonsurvey Methods: The Role of Cross-Hauling"
2012
This article examines the effectiveness of a new non-survey regionalization method: Kronenberg’s Cross-Hauling Adjusted Regionalization Method (CHARM). This aims to take into account the fact that regions typically both import and export most commodities. Data for Uusimaa, Finland’s largest region, are employed to carry out a detailed empirical test of CHARM. This test gives very encouraging results. CHARM is suitable for studying environmental questions, but it can only be applied in situations where foreign imports have been included in the national input–output table. Where the focus is on regional output and employment, location quotients (LQs) can be used for purposes of regionalizati…
Determination of urea-derived pesticides in fruits and vegetables by solid-phase preconcentration and capillary electrophoresis
2001
A multiresidue analytical method based on solid-phase extraction (SPE) enrichment combined with capillary electrophoresis (CE), using micellar electrokinetic capillary chromatography (MEKC), was developed to determine ten substituted urea pesticides in orange and tomato samples. Several factors such as pH, composition and concentration of the buffer, concentration of surfactant, addition of organic solvent, and working voltage were optimized to obtain the best compound separation in the shortest time. Separation can be achieved in 7 min using a micellar aqueous pH 9 buffer composed of 4 mM borate and 35 mM sodium dodecyl sulfate. After an SPE procedure, which provided a 10-fold enrichment, …
Physiological Perturbations in Several Generations of Daphnia magna Straus Exposed to Diazinon
2000
Abstract Daphnia magna was exposed to sublethal diazinon concentrations (0.05, 0.1, 0.5, 0.75, and 1.0 ng/L) for 21 days. The algae Nannochloris oculata (5×10 5 cells/mL) was used to feed the daphnids. Chronic toxicity tests were carried out using neonates of F 1 (first brood) and F 1 (third brood) offspring generations from parentals (F 0 ) preexposed to the organophosphate. The effect of diazinon on survival, reproduction, and growth was monitored for the selected daphnid generations. The parameters used to evaluate pesticide effect on reproduction were mean total young per female, mean brood size, time to first reproduction, mean number broods per female, and intrinsic rate of natural in…
Uptake and bioavailability of persistant organic pollutants by plants grown in contaminated soil
2005
This paper assesses the uptake of persistent organic pollutants (POP's) into plants. In particular, uptake of alpha-endosulfan, beta-endosulfan and endosulfan sulfate from lettuce. The lettuce plants were grown on compost that had previously been contaminated at 10 and 50 microg g(-1) per POP. The soil was slurry spiked by adding the appropriate amount of POP in acetone in an approximate ratio of 1 ratio 2, w/v soil ratio solvent. The solvent was left to evaporate at ambient temperature for 24 hours. Lettuce plants were grown under artificial daylight for 12 hours a day. The influence of soil ageing on the recovery of POP's from spiked soil samples was also assessed. The average recovery of…
Assessment of Organochlorine Pesticide Residues in West African City Farms: Banjul and Dakar Case Study
2003
Validated analytical procedures for the determination of 21 organochlorine pesticides have been applied to 74 water samples, 76 soil samples, and 160 vegetable samples from nine Sene-Gambian farms. Mean pesticide residue levels found were compared to the results of other studies. The main contaminants were DDTs in water (231.9 ng/L), in soil (71.4 ng/g), and in vegetables (5.03 ng/g). The distribution of pesticide residues in water and neighboring soils and the soil-plant transfer of these pesticides is briefly discussed. Different bioconcentration factors for sum HCHs, sum DDTs, and sum endosulfans obtained in this study allow us to confirm the complex processes already reported in the lit…
Vers une tridimensionalité du contrôle interactif
2011
We propose in this paper to revisit the concept of interactive control, highlighted by Robert Simons, examining the use of "environmental control systems" in Ten French Companies proactive in ecology. By showing that interactivity of "control systems" is not limited to a vertical dimension as suggested by Simons, but it tends towards three-dimensional (vertical, transversal and external), this study highlights the interest of explore further upstream the concept of interactive control little studied in the literature.
Feasibility, limitations and potentiality of UHF-RFID passive implants
2012
Implanted RFID may play an important role in the personal Healthcare of next future. Antenna embedded into prosthesis or into other implanted medical devices could permit to monitor physiological and pathological processes, providing a natural interconnection to remote services. The big technical challenge is to establish a stable RFID link with the interior of the human body in spite of the high electromagnetic losses of the tissues. By using parametric electromagnetic models and some early result, it is here investigated the potentiality and limitation of the UHF implants with special attention to the body district, the overall mass, and the size of the antennas.