Investment and capital dynamics under long-term changes in marine fish communities: the case of French fleets exploiting the Bay of Biscay fisheries

This paper deals with capital mobility for artisanal vessels (of less than 24 meters in length) and with its structural adaptation, considering long-term changes in marine fish communities, using the Bay of Biscay fisheries as a case study. Long term changes are related to the impacts of fishing, to changes in the physical environment as climate change, or both. Hence, changes in the relative abundance of species in a fish community have impacted fisheries but at different degrees according to individual fishing strategies implemented. The aim is to valuate the probability for a boat to leave the fleet in terms of its technical characteristics, economic performance and of its localisation, under long-term changes in marine fish communities. This probability has all the more an important play on the regional economic activity than fishing industry is highly regionally based. The estimated model is a logit model, which also estimates the marginal effect of explanatory variables on the leaving probability. Particularly, we study the effect of boat characteristics and economic results on this probability. This leads to a logistic curve of a growing rate of the probability to leave the fleet. The rate value is not constant but changes in terms of fishing boats age, in contrast with the result obtained in the linear probabilistic model.Keywords: Marine fishing communities, Regional economic activity, Long term changes, Investment and capital dynamics, Fisheries Economics, Bay of BiscayKeywords: Marine fishing communities, Regional economic activity, Long term changes, Investment and capital dynamics, Fisheries Economics, Bay of Bisca

Estimating Capital Value and Depreciation of Fishing Fleets: Application to French Fisheries

While the need to solve problems of overcapitalization and excess investment in fisheries is now broadly admitted, very little information exists on the level of capitalization and the structure of capital invested in the fishing sector. This paper presents the first results of a research program aiming at assessing the value of capital, investments and depreciation in fisheries. Results presented are derived from a field survey operated by Ifremer and record transaction on the fishing vessel second hand market. Statistical analysis is carried out according to a set of fishing components, such as vessel hull, engine, electronics and storage equipment. Firstly, hedonic price functions are estimated for the vessel and its main components. Secondly, a depreciation function of vessels according to their age and fleet is proposed. Finally, indicators of gross value of capital, net physical value as well as market value are estimated for different significant groups of fishing units belonging to the NSCA less than 24 m. fleet

Construction and test of a fine-grained liquid argon preshower prototype

A separate liquid argon preshower detector consisting of two layers featuring a fine granularity of 2.5~10$^{\mathrm{-3}}$ was studied by the RD3 collaboration. A prototype covering approximately 0.8 in pseudo-rapidity and 9 degrees in azimuth was built and tested at CERN in July 94. CMOS and GaAs VLSI preamplifiers were designed and tested for this occasion. The combined response of this detector and an accordion electromagnetic calorimeter prototype to muons, electrons and photons is presented. For minimum ionizing tracks a signal-to-noise ratio of 4.5 per preshower layer was measured. Above 150~GeV the space resolution for electrons is better than 250~$\mu$m in both directions. The precision on the electromagnetic shower direction, determined together with the calorimeter, is better than 4 mrad above 50~GeV. It is concluded that the preshower detector would adequately fulfil its role for future operation at CERN Large Hadron Collider

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The acoplanar photon pairs produced in the reaction e(+) e(-) - → vvyy are analysed in the 700 pb(-1) of data collected by the ALEPH detector at centre-of-mass energies between 183 and 209 GeV. No deviation from the Standard Model predictions is seen in any of the distributions examined. The resulting 95% C.L. limits set on anomalous QGCs, a(0)(Z), a(c)(Z), a(0)(W) and a(c)(W), are -0.012 lt a(0)(Z)/Lambda(2) lt +0.019 GeV-2, -0.041 lt a(c)(Z)/Lambda(2) lt +0.044 GeV-2, -0.060 lt a(0)(W)/Lambda(2) lt +0.055 GeV-2, -0.099 lt a(c)(W)/Lambda(2) lt +0.093 GeV-2, where Lambda is the energy scale of the new physics responsible for the anomalous couplings

Absolute mass lower limit for the lightest neutralino of the MSSM from e+e−e^{+}e^{-} data at s\sqrt{s} up to 209 GeV

Charginos and neutralinos are searched for in the data collected by the ALEPH experiment at LEP for centre-of-mass energies up to 209 GeV. The negative result of these searches is combined with those from searches for sleptons and Higgs bosons to derive an absolute lower limit of 43.1 GeV/c(2) on the mass of the lightest supersymmetric particle (LSP), assumed to be the,lightest neutralino. This limit is obtained in the framework of the MSSM with R-parity conservation and with gaugino and sfermion mass unification at the GUT scale and assuming no mixing in the stau sector. The LSP limit degrades only slightly to 42.4 GeV/c(2) if stau mixing is considered. Within the more constrained framework of minimal supergravity, the limit is 50 GeV/c(2)

Measurement of the W mass in e+e−e^+ e^- collisions at 183 GeV

The mass of the W boson is obtained from reconstructed invariant mass distributions in W-pair events. The sample of W pairs is selected from 57 pb$^{-1}$ collected with the ALEPH detector in 1997 at a centre-of-mass energy of 183 GeV. The invariant mass distributions of reweighted Monte Carlo events are fitted separately to the experimental distributions in the $qqbarqqbar$ and all l\nuqqbar channels to give the following W masses: $m_{W}^{hadronic} = 80.461 \pm 0.177(stat.) \pm 0.045(syst.) \pm 0.056(theory) GeV/c^2$, $m_{W}^{semileptonic} = 80.326 \pm 0.184(stat.) \pm 0.040(syst.) GeV/c^2$ where the theory error represents the possible effects of final state interactions. The combination of these two measurements, including the LEP energy calibration uncertainty, gives $m_{W} = 80.393 \pm 0.128(stat.)\pm 0.041(syst.) \pm 0.028(theory)\pm 0.021(LEP) GeV/c^2

Comment réduire l'impact du développement périurbain sur les petits cours d'eau ? Cas de l'ouest lyonnais

[Departement_IRSTEA]Eaux [TR1_IRSTEA]ARCEAU [TR2_IRSTEA]QUASARENational audienceLe sujet présenté s'appuie sur une étude réalisée dans le cadre d'un contrat de rivière. Il concerne la définition d'un observatoire des effets des actions menées pour améliorer et préserver la qualité des cours d'eau d'un bassin périurbain soumis à un développement urbain soutenu. La définition de l'observatoire est avant tout le fruit d'un partenariat de plusieurs années entre scientifiques et la structure porteuse du contrat qui regroupe les collectivités concernées. Les scientifiques apportent la vision de synthèse du fonctionnement du cours d'eau à partir des nombreuses études techniques réalisées dans le cadre du contrat et des études scientifiques réalisées en parallèle au travers d'une convention d'appuis scientifique. Le contrat met en retour à disposition l'ensemble des données des études qu'il a financées

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Investment and capital dynamics under long-term changes in marine fish communities : the case of French fleets exploiting the Bay of Biscay fisheries

International audienceThis paper deals with capital mobility for artisanal vessels (of less than 24 meters in length) and with its structural adaptation, considering long-term changes in marine fish communities, using the Bay of Biscay fisheries as a case study. Long term changes are related to the impacts of fishing, to changes in the physical environment as climate change, or both. Hence, changes in the relative abundance of species in a fish community have impacted fisheries but at different degrees according to individual fishing strategies implemented. The aim is to valuate the probability for a boat to leave the fleet in terms of its technical characteristics, economic performance and of its localisation, under long-term changes in marine fish communities. This probability has all the more an important play on the regional economic activity than fishing industry is highly regionally based. The estimated model is a logit model, which also estimates the marginal effect of explanatory variables on the leaving probability. Particularly, we study the effect of boat characteristics and economic results on this probability. This leads to a logistic curve of a growing rate of the probability to leave the fleet. The rate value is not constant but changes in terms of fishing boats age, in contrast with the result obtained in the linear probabilistic model