Status and management of tropical coastal fisheries in Asia

Coastal fisheries, Fishery management, Stock assessment, Conferences, Asia,

Fractal Photonic Crystal Waveguides

We propose a new class of one-dimensional (1D) photonic waveguides: the fractal photonic crystal waveguides (FPCWs). These structures are photonic crystal waveguides (PCWs) etched with fratal distribution of grooves such as Cantor bars. The transmission properties of the FPCWs are investigated and compared with those of the conventional 1D PCWs. It is shown that the FPCW transmission spectrum has self-similarity properties associated with the fractal distribution of grooves. Furthermore, FPCWs exhibit sharp localized transmissions peaks that are approximately equidistant inside the photonic band gap

Detection and resolution of normative conflicts in multi-agent systems : a literature survey

Peer reviewedPostprin

Production and detection of doubly charmed tetraquarks

The feasibility of tetraquark detection is studied. For the cc\bar{u}\bar{d} tetraquark we show that in present (SELEX, Tevatron, RHIC) and future facilities (LHCb, ALICE) the production rate is promising and we propose some detectable decay channels.Comment: 6 pages, 5 figure

Pentaquarks uuddqˉuudd\bar q with One Color Sextet Diquark

The masses of pentaquarks $uudd\bar s$ are calculated within the framework of a semirelativistic effective QCD Hamiltonian, using a diquark picture. This approximation allows a correct treatment of the confinement, assumed here to be similar to a Y-junction. With only color antitriplet diquarks, the mass of the pentaquark candidate $\Theta$ with positive parity is found around 2.2 GeV. It is shown that, if a color sextet diquark is present, the lowest $uudd\bar s$ pentaquark is characterized by a much smaller mass with a negative parity. A mass below 1.7 GeV is computed, if the masses of the color antitriplet and color sextet diquarks are taken similar

Experiências da prática profissional na reabilitação: análise de um grupo de foco

O objetivo desta investigação foi reconhecer as perceções dos múltiplos intervenientes acerca dos problemas encontrados nos processos de reabilitação do património habitacional. Os dados foram recolhidos através de um inquérito orientado para um grupo de foco. O estudo contou com um total de 108 participantes, incluindo arquitetos, engenheiros, construtores e técnicos de construção e restauro e potenciais promotores. Os dados foram analisados com recurso a métodos de investigação qualitativa, nomeadamente análises temáticas e de conteúdo. Os resultados demonstram que os principais problemas identificados estão relacionados com a informação, com o fator económico, com a perceção social e a qualificação dos intervenientes. Foi também possível identificar aspetos positivos no processo, nomeadamente a motivação encontrada em participar na valorização do carácter dos lugares, mas também um maior reconhecimento dos contributos das técnicas tradicionais para a sustentabilidade. Os resultados demonstram que, para que as boas práticas de reabilitação sejam aplicadas de modo efetivo, é necessário melhorar a transmissão dessa informação para a prática profissional, criando ferramentas que permitam apoiar a tomada de decisão ponderada, considerando um leque mais abrangente de critérios para além do económico (como o impacte ambiental, a saúde dos ocupantes, ou o valor patrimonial).info:eu-repo/semantics/publishedVersio

Influence of anisotropic ion shape, asymmetric valency, and electrolyte concentration on structural and thermodynamic properties of an electric double layer

Grand canonical Monte Carlo simulation results are reported for an electric double layer modelled by a planar charged hard wall, anisotropic shape cations, and spherical anions at different electrolyte concentrations and asymmetric valencies. The cations consist of two tangentially tethered hard spheres of the same diameter, $d$. One sphere is charged while the other is neutral. Spherical anions are charged hard spheres of diameter $d$. The ion valency asymmetry 1:2 and 2:1 is considered, with the ions being immersed in a solvent mimicked by a continuum dielectric medium at standard temperature. The simulations are carried out for the following electrolyte concentrations: 0.1, 1.0 and 2.0 M. Profiles of the electrode-ion, electrode-neutral sphere singlet distributions, the average orientation of dimers, and the mean electrostatic potential are calculated for a given electrode surface charge, $\sigma$, while the contact electrode potential and the differential capacitance are presented for varying electrode charge. With an increasing electrolyte concentration, the shape of differential capacitance curve changes from that with a minimum surrounded by maxima into that of a distorted single maximum. For a 2:1 electrolyte, the maximum is located at a small negative $\sigma$ value while for 1:2, at a small positive value.Comment: 10 pages, 6 figure

Double layer for hard spheres with an off-center charge

Simulations for the density and potential profiles of the ions in the planar electrical double layer of a model electrolyte or an ionic liquid are reported. The ions of a real electrolyte or an ionic liquid are usually not spheres; in ionic liquids, the cations are molecular ions. In the past, this asymmetry has been modelled by considering spheres that are asymmetric in size and/or valence (viz., the primitive model) or by dimer cations that are formed by tangentially touching spheres. In this paper we consider spherical ions that are asymmetric in size and mimic the asymmetrical shape through an off-center charge that is located away from the center of the cation spheres, while the anion charge is at the center of anion spheres. The various singlet density and potential profiles are compared to (i) the dimer situation, that is, the constituent spheres of the dimer cation are tangentially tethered, and (ii) the standard primitive model. The results reveal the double layer structure to be substantially impacted especially when the cation is the counterion. As well as being of intrinsic interest, this off-center charge model may be useful for theories that consider spherical models and introduce the off-center charge as a perturbation.Comment: 11 pages, 7 figure

The Chances to Produce and Detect the b-b-ubar-dbar Tetraquark at LHC

In the LHC collider a significant rate of events with double parton scattering is expected. This will be the leading mechanism for production of two b-bbar pairs. We estimate the probability of binding two b quarks into a diquark and the probability of dressing this diquark into a b-b-ubar-dbar ISP=01+ tetraquark. Calculations shows that that this bound state of two B mesons is stable against the strong interaction and has a life time of the order of ps. We estimate that the production rate at luminosity L=0.1 events per second will be about 6 tetraquarks per hour or more.Comment: Contributed talk at the XVIII European Conference on Few-Body Problems in Physics, September 8-14, Bled, Slovenia, 4 pages LaTe

Survey to architects: challenges to inspection and diagnosis in historical residential buildings

Using a web query among architects (n=57), we could identify the main obstacles found in the application of inspection and diagnosis procedures in historical residential buildings.  The results revealed that these procedures are not yet uniformly applied in this built heritage and pointed out the need to develop simplified methodologies and less resource-consuming methodologies, to ensure their applicability.The authors would like to acknowledge the support granted by the Portuguese Foundation for Science and Technology (FCT), in the scope of the Doctoral Program Eco-Construction and Rehabilitation (EcoCoRe), to the PhD scholarship with the reference PD/BD/127853/2016 that was fundamental for the development of this study.info:eu-repo/semantics/publishedVersio