Investment Behaviour and Capacity Adjustment in Fisheries: A Survey of the Literature

This article provides a survey of the economic literature on investment behaviour and capacity adjustment in fisheries. An overview of the existing theoretical and the empirical work is provided, and areas that require more work are pointed out. The survey shows that while a large body of theoretical work has been developed on the issue of capital adjustment in fisheries, relatively less attention has been granted to the theory of investment, where this becomes a separate decision to the decision about capital levels; i.e., where capital is quasi-malleable. In addition, empirical studies have been fairly limited, and more work is still needed to analyse and further investigate these issues in practical situations. There is particularly a need for more empirical studies of investment behaviour and drivers of investment behaviour at the firm level based on adequate economic data.Investment, capital adjustment, capacity, ITQs, fisheries, Public Economics, Research and Development/Tech Change/Emerging Technologies, Research Methods/ Statistical Methods, Teaching/Communication/Extension/Profession, Q22,

Phase space shifts in command structures in networked systems

This paper presents the rationale behind an important enhancement to the NATO SAS-050 approach space, combined with empirical results which take advantage of these enhancements. In Part 1 a new theoretical legacy for the NATO model is presented. This legacy inspires a number of developments which allow live data to be plotted into it, and we demonstrate that the model is well able to discriminate between alternative C2 structures. Part 2 illustrates this feature with multinational data from the ELICIT community. It is surprising to see that teams in both C2 and Edge conditions operate in broadly the same area of the phase space cube. The structure of the pre-ordained ELICIT ‘classic C2’ hierarchy and the deterministic nature of the shared task are put forward as explanations for this, and as future enhancements to the ELICIT paradigm

Doctor of Philosophy

dissertationPrior evidence from several research areas suggests that performance improvements can accrue during intervals that preclude further practice of a procedural skill; however, the mechanism underlying this improvement is unclear. In order to test competing explanations for such improvement, the author investigated the effects of varying the cognitive demands of a secondary task interpolated into a course of cognitive skill practice. The moderately complex skill task that was used presented electrical circuitry operations (logic gates) and their corresponding rules, which participants learned first through declarative instruction and thereafter through multiple blocks of procedural practice. The interpolated task was either a cognitively demanding working memory (WM) test or a noncognitively demanding period spent listening to binaural alpha-wave beats over headphones. Three theory-based explanations for skill improvement during the interpolated task, or gap facilitation, were tested: memory consolidation, release from proactive interference (PI), and mental rest. Each explanation makes unique predictions regarding parameters of a power function used to describe the trajectory of each participant's skill performance before and after the interpolated tasks. Evidence favored release from PI as being responsible for the observed gap facilitation effects. Findings are interpreted with respect to learning theory that predicts performance decline with time away from practice and in light of prior explanations of evidence to the contrary

Analyzing The Organization Of Animal Behavior: The Application Of Nonsymmetric Multidimensional Scaling Techniques

Several multidimensional quantitative approaches have been applied to the analysis of the organization of behavior. These include chi square, lag sequence analysis, and non-symmetric multidimensional scaling techniques. Transition matrices are generally asymmetric and this is a problematic feature for the first two techniques noted above. Hence is is argued that non-symmetric multidimensional scaling (MDS) techniques are the most appropriate for the analysis of such data sets.;To illustrate these three techniques and to evaluate non-symmetric MDS as a valuable new tool which has been underutilized by ethologists, observational data were collected in a focal animal study of two members of a captive family of meerkats (Suricata curicatta). The results of chi square analyses showed that meerkat behavior could be divided into three major groups--Solitary Behavior, Active Interactions and Passive Interactions. The patterns of relationship between these major groups of activities, were ascertained using a non-symmetric MDS program called DEDICOM. Solitary activities could be grouped into subclasses labeled foraging, self maintenance and reconnaissance. Clear patterns of transition between these smaller units were identified using MDS DEDICOM. Also solitary activities are more likely to be followed by Passive Interactions than Active ones. Active Interactions are highly likely to change into Passive Interactions before they are terminated. Lag sequence analyses identified clusters of activities similar to those found using the other two analytical approaches.;Of the three techniques applied, lag sequence analysis was the most difficult to apply and interpret. The chi square analyses produced informative results but still required a degree of subjective analysis. MDS DEDICOM provided clear information both about the clustering of activities into related classes and the patterns of transition between these subgroups. It was concluded that non-symmetric MDS techniques offer the best alternative for the analysis of behavioural organization when the data set to be analyzed is an asymmetric matrix. The simplicity and appropriateness of this technique makes it an extremely valuable tool for the student of behavioural organization

Imposing high-symmetry and tuneable geometry on lanthanide centres with chelating Pt and Pd metalloligands

Exploitation of HSAB preferences allows for high-yield, one-pot syntheses of lanthanide complexes chelated by two Pd or Pt metalloligands, [MII(SAc)4]2− (SAc− = thioacetate, M = Pd, Pt). The resulting complexes with 8 oxygen donors surrounding the lanthanides can be isolated in crystallographically tetragonal environments as either [NEt4]+ (space group: P4/mcc) or [PPh4]+ (space group: P4/n) salts. In the case of M = Pt, the complete series of lanthanide complexes has been structurally characterized as the [NEt4]+ salts (except for Ln = Pm), while the [PPh4]+ salts have been structurally characterized for Ln = Gd–Er, Y. For M = Pd, selected lanthanide complexes have been structurally characterized as both salts. The only significant structural difference between salts of the two counter ions is the resulting twist angle connecting tetragonal prismatic and tetragonal anti-prismatic configurations, with the [PPh4]+ salts approaching ideal D4d symmetry very closely (φ = 44.52–44.61°) while the [NEt4]+ salts exhibit intermediate twist angles in the interval φ = 17.28–27.41°, the twist increasing as the complete 4f series is traversed. Static magnetic properties for the latter half of the lanthanide series are found to agree well in the high temperature limit with the expected Curie behavior. Perpendicular and parallel mode EPR spectroscopy on randomly oriented powder samples and single crystals of the Gd complexes with respectively Pd- and Pt-based metalloligands demonstrate the nature of the platinum metal to strongly affect the spectra. Consistent parametrization of all of the EPR spectra reveals the main difference to stem from a large difference in the magnitude of the leading axial term, B02, this being almost four times larger for the Pt-based complexes as compared to the Pd analogues, indicating a direct Pt(5dz2)–Ln interaction and an arguable coordination number of 10 rather than 8. The parametrization of the EPR spectra also confirms that off-diagonal operators are associated with non-zero parameters for the [NEt4]+ salts, while only contributing minimally for the [PPh4]+ salts in which lanthanide coordination approximates D4d point group symmetry closely.LHD acknowledges support from NSF-CCT EMT 08-517. (08-517 - NSF-CCT EMT

Measurement of the magnetic octupole susceptibility of PrV2Al20

In the electromagnetic multipole expansion, magnetic octupoles are the subsequent order of magnetic multipoles allowed in centrosymmetric systems, following the more commonly observed magnetic dipoles. As order parameters in condensed matter systems, magnetic octupoles have been experimentally elusive. In particular, the lack of simple external fields that directly couple to them makes their experimental detection challenging. Here, we demonstrate a methodology for probing the magnetic octupole susceptibility using a product of magnetic field $H_i$ and shear strain $\epsilon_{jk}$ to couple to the octupolar fluctuations, while using an adiabatic elastocaloric effect to probe the response to this composite effective field. We observe a Curie-Weiss behavior in the obtained octupolar susceptibility of \ce{PrV2Al20} up to temperatures approximately forty times the putative octupole ordering temperature. Our results demonstrate the presence of magnetic octupole fluctuations in the particular material system, and more broadly highlight how anisotropic strain can be combined with magnetic fields to formulate a versatile probe to observe otherwise elusive emergent `hidden' electronic orders.Comment: 7 pages, 3 figure