Use of a fishery independant index to predict recruitment and catches of the spiny lobster

This paper presents a review of recruitment and catch predictions based on an index of abundance of juveniles and pre-recruits (fishery independent index) in the Cuban lobster fisheries. This methodology can provide information based on fisheries data that can improve the management of the fishery.Coral reefs, Indicators, Fishery resources, Resource management, Ecosystem management

The nuclear contacts and short range correlations in nuclei

Atomic nuclei are complex strongly interacting systems and their exact theoretical description is a long-standing challenge. An approximate description of nuclei can be achieved by separating its short and long range structure. This separation of scales stands at the heart of the nuclear shell model and effective field theories that describe the long-range structure of the nucleus using a mean- field approximation. We present here an effective description of the complementary short-range structure using contact terms and stylized two-body asymptotic wave functions. The possibility to extract the nuclear contacts from experimental data is presented. Regions in the two-body momentum distribution dominated by high-momentum, close-proximity, nucleon pairs are identified and compared to experimental data. The amount of short-range correlated (SRC) nucleon pairs is determined and compared to measurements. Non-combinatorial isospin symmetry for SRC pairs is identified. The obtained one-body momentum distributions indicate dominance of SRC pairs above the nuclear Fermi-momentum.Comment: Accepted for publication in Physics Letters. 6 pages, 2 figure

Optimization of composite sandwich cover panels subjected to compressive loadings

An analysis and design method is presented for the design of composite sandwich cover panels that include the transverse shear effects and damage tolerance considerations. This method is incorporated into a sandwich optimization computer program entitled SANDOP. As a demonstration of its capabilities, SANDOP is used in the present study to design optimized composite sandwich cover panels for for transport aircraft wing applications. The results of this design study indicate that optimized composite sandwich cover panels have approximately the same structural efficiency as stiffened composite cover panels designed to satisfy individual constraints. The results also indicate that inplane stiffness requirements have a large effect on the weight of these composite sandwich cover panels at higher load levels. Increasing the maximum allowable strain and the upper percentage limit of the 0 degree and +/- 45 degree plies can yield significant weight savings. The results show that the structural efficiency of these optimized composite sandwich cover panels is relatively insensitive to changes in core density. Thus, core density should be chosen by criteria other than minimum weight (e.g., damage tolerance, ease of manufacture, etc.)

An application of adaptive learning to malfunction recovery

A self-organizing controller is developed for a simplified two-dimensional aircraft model. The Controller learns how to pilot the aircraft through a navigational mission without exceeding pre-established position and velocity limits. The controller pilots the aircraft by activating one of eight directional actuators at all times. By continually monitoring the aircraft's position and velocity with respect to the mission, the controller progressively modifies its decision rules to improve the aircraft's performance. When the controller has learned how to pilot the aircraft, two actuators fail permanently. Despite this malfunction, the controller regains proficiency at its original task. The experimental results reported show the controller's capabilities for self-organizing control, learning, and malfunction recovery

Transaction Costs and Housing Affordability in Asia

Asia is home to some of the fastest growing cities in the world. As urbanization increases, demand for housing also increases. Well functioning housing markets can minimize problems associated with rapid urbanization such as unaffordable housing and urban slums. This paper explores the different aspects of the residential property sales markets in Asian countries. Using data gathered by the Global Property Guide, transaction costs associated with residential property purchases are analyzed. Housing markets are also examined in terms of tenure, protection of property rights, and openness and transparency. Roundtrip transaction costs for buying properties are high, above 10% in several countries in Asia. High transaction costs and unaffordable housing combined with weak protection of property rights are seen to be conducive to the creation of urban slums.Property markets, Transaction costs, Housing affordability, Slums

Geodesic Structure of Lifshitz Black Holes in 2+1 Dimensions

We present a study of the geodesic equations of a black hole space-time which is a solution of the three-dimensional NMG theory and is asymptotically Lifshitz with $z=3$ and $d=1$ as found in [Ayon-Beato E., Garbarz A., Giribet G. and Hassaine M., Phys. Rev. {\bf D} 80, 104029 (2009)]. By means of the corresponding effective potentials for massive particles and photons we find the allowed motions by the energy levels. Exact solutions for radial and non-radial geodesics are given in terms of the Weierstrass elliptic $\wp$, $\sigma$, and $\zeta$ functions.Comment: 10 pages, 6 figures, accepted for publication in Eur. Phys. J.

Carbon and titanium diboride (TiB2) multilayer coatings.

Titanium Diboride, (TiB2) is a metal-based refractory ceramic material that has been investigated in industrial applications ranging from, cutting tools to wear parts and for use in the aerospace industry. The unique properties which make this material so fascinating are, its high hardness, high melting point and its corrosion resistance. TiB2 is prevented from wider mainstream use because of its inherent brittle nature. With a view to overcome this in coating form and with the aim of providing in addition inherent lubricity, in this study 50 layer TiB2/C multilayer stacks have been fabricated, with varying volume fractions of ceramic, whereby the interfaces of the layers limit crack propagation in the TiB2 ceramic. TiB2 has been multilayered with carbon, to make use of the unique and hybrid nature of the bonding in carbon coatings. DC magnetron sputtering with substrate bias was the preferred route for the fabrication of these coatings. AISI tool steel has been used as the substrate material. By varying the amount of TiB2 ceramic from 50% to 95%, the Hardness of the coating is seen to increase from 5 GPa to 17GPa. The Hardness is observed to decrease as a function of increasing carbon content, agreeing with other studies that the carbon layers are not load-bearing. The graphitic nature of the sp2 bond, however, acts as a lubricant layer