A Cooperative Management Solution to a Fishery Commons

A common property resource with open access, such as a fishery, will be used to excess when faced with sufficient demand. This will lead to an excessive amount of effort on the part of the fishery, resulting in a depletion of the stock. This paper discusses the development of a property rights regime for the Atlantic calico scallop, Argopecten gibbus, fishery of Florida. The management solution of the Calico Scallop Conservation Association (CSCA) provides an example of the assignment of property rights to a common property resource without resorting to governmental intervention. In this particular fishery, self-regulation limited early harvesting which would be uneconomic; there may be other fisheries in which self-regulation could be economically efficient and biologically appropriate. While this solution may not be applicable to all common property resources, for those cases which may be similar; the example of the CSCA provides valuable information that may be helpful in establishing a more efficient use of the resource. Some types of government facilitation may also be useful

Automatic and frequency-programmable systems for feeding TMR: state of the art and available technologies

La tecnica di razionamento TMR (Total Mixed Ration) per bovine da latte si \ue8 molto diffusa grazie ai vantaggi offerti. La meccanizzazione si basa su carri miscelatori azionati da operatore. Alcuni limiti sono associabili alla bassa frequenza di distribuzione (1-2 volte/giorno). La recente diffusione di sistemi automatici per la preparazioone e distribuzione di TMR consente di introdurre inedite possibilit\ue0 di gestione dell'alimentazione. Circa 15 costruttori operanti su diversi concetti progettuali sono stati individuati. Tra le principali innovazioni vi \ue8 la possibilit\ue0 di variare la frequenza di distribuzione, modulare la razione, controllare gli orari di distribuzione, stimolare l'attivit\ue0 delle bovine, gestire l'ingestione di sostanza secca. Il lavoro presenta una panoramica sullo stato dell'arte della tecnologia e propone una classificazione dei robot per TMR

Doing business with animals : moral entrepreneurship and ethical room for manoeuvre in livestock related sector

The overall objective of this dissertation is to study moral entrepreneurship within animal and business ethics in relation to moral change. In particular the current capability in bringing about moral change and its potential to do so

Interpreting Southern California Arc Geochemistry by Multivariate and Spatial Methods

Exploratory data analysis methods of multivariate statistical techniques and spatial visualization are emerging trends in understanding big datasets. In this project, these techniques are applied to a large igneous geochemical dataset from the southern California segment of the Mesozoic Cordilleran arc to better understand magmatic and plate tectonic processes at a subduction zone. A set of 287 granitic samples collected by Baird and Miesch (1984) from the Peninsular Ranges batholith is analyzed for 38 geochemical elements. Patterns in both the geochemical variation and the spatial variation of this dataset are explored. Since geochemical data are compositional in nature, special treatment is needed in analyzing them. Robust principal component analysis for compositional data is used to summarize the 38 geochemical variables into three principal components that are visualized using biplots. The first three principal components appear to be related to extent of differentiation, magma source depth, and possibly solubility, respectively. The first principal component (PC1) accounting for 56.7% of the explained variance, arranges the elements in order of incompatibility. The main associations of PC2 (17.3% of explained variance) are groupings of rare earth elements, along with Y and Sr – suggesting the effect of deep garnet and shallow plagioclase fractionation in response to pressure and therefore depth. A weak association of soluble elements is found in PC3 (6.7% of explained variance). Spatial geochemical variation is explored by mapping the standard geochemical parameters related to the principal component interpretations as well as the three principal components, and then comparing them. Extent of differentiation is mapped using SiO2 and PC1 and resulting maps show similar patterns. Magma source depth is mapped using Sr/Y, La/Yb and PC2 and similar patterns are found. Alkalinity and possibly solubility and mobility is mapped using K2O/SiO2 and PC3, but these maps do not share similar patterns. Using the exploratory data analysis methods of multivariate analysis and spatial visualization is helpful in understanding geochemical patterns and trends in subduction zones

Dissociative adsorption of methane on surface oxide structures of Pd-Pt alloys

The dissociative adsorption of methane on variously oxidized Pd, Pt and Pd-Pt surfaces is investigated using density-functional theory, as a step towards understanding the combustion of methane on these materials. For Pd-Pt alloys, models of surface oxide structures are built on the basis of known oxides on Pd and Pt. The methane adsorption energy presents large variations depending on the oxide structure and composition. Adsorption is endothermic on the bare Pd(111) metal surface as well as on stable thin layer oxide structures such as the ($\sqrt{5}\times\sqrt{5}$) surface oxide on Pd(100) and the PtO$_2$-like oxide on Pt(111). Instead, large adsorption energies are obtained for the (100) surface of bulk PdO, for metastable mixed Pd$_{1-x}$Pt$_x$O$_{4/3}$ oxide layers on Pt(100), and for Pd-Pt(111) surfaces covered with one oxygen monolayer. In the latter case, we find a net thermodynamic preference for a direct conversion of methane to methanol, which remains adsorbed on the oxidized metal substrates via weak hydrogen-bond interactions