João Dias

Creating individual agents through personality traits

In the era of globalization, concepts such as individualization and personalization become more and more important in virtual systems. With the goal of creating a more familiar interaction between human and machines, it makes sense to create a consistent and believable model of personality. This paper presents an explicit model of personality, based in the Five Factor Model, which aims at the creation of distinguishable personalities by using the personality traits to automatically influence cognitive processes: appraisal, planning, coping, and bodily expression.

Innocence and noninnocence of the ligands in bis(pyrazine-2,3-dithiolate and -diselonate) d8-metal complexes. A theoretical and experimental study for the Cu(III), Au(III) and Ni(II) cases

In this paper we present an experimental and theoretical study to investigate the electronic structures of [ML₂]⁻ (M(III) = Cu, L = pdt and pds, pyrazine-2,3-dithiolate and -diselonate; M(III) = Au, L = pds) with the aim of elucidating the nature of the bonding and to establish the innocent-noninnocent character of the ligand in these complexes. Calculations based on DFT methods have been performed to obtain geometry optimizations, harmonic frequencies, IR intensities and Raman scattering activities. The experimental vibrational spectra are accurately reproduced by the calculations, which show that CC, CN, and CX (X = S, Se) vibrations are extensively mixed with other modes, and thus unsuitable to work as vibrational markers. Geometry optimization performed at the DFT level provides geometrical parameters in good agreement with the available structural data. The energetic sequence and nature of the redox-active molecular orbitals help to elucidate the observed electrochemical behaviour. Accordingly, the quasi-reversible redox couple for the reduction processes exhibited by [ML₂]²⁻ (L = pdt and pds), that appears at negative values and depends both on the ligand and on the metal, is related to the LUMO which is a σ antibonding combination of the ligand orbitals (sulfur or selenium atoms) and the 3d(xy) (Cu) and 5d(xy) (Au) metal orbitals. The HOMO is a π-orbital with a b(2g) symmetry, predominantly ligand in character with a small contribution of the nd(xz) atomic orbitals in antibonding combination with chalcogen atom orbitals. The low energy of the metal d-orbitals compared to the ligand orbitals, due to the high effective nuclear charge of the metals, explains their small participation to this orbital. Thus in [ML₂]⁻ the metals approach the oxidation state 3+ and the ligand a dichalcogenolate description and thus a prevalent innocent character. However the same ligand shows a noninnocent character in complexes with a different d⁸ metal such as Ni(II) whose d-orbitals lie at higher energies and mix at a higher extent with the ligand orbitals in the HOMO.

A new hybrid material exhibiting room temperature spin-crossover and ferromagnetic cluster-glass behavior

A new compound, [Fe(5–Cl-qsal)2][Ni(α-tpdt)2].CH3CN, where α-tpdt = 2,3-thiophenedithiolate and H5–Cl-qsal = N-(8-quinolyl)-5-chlorosalicylaldimine, was prepared and structurally and magnetically characterized. The crystal structure is based on an arrangement of alternate layers of [Fe(5–Cl-qsal)2]+ cations and [Ni(α-tpdt)2]− anions. The magnetic measurements and Mossbauer spectroscopy revealed hybrid behavior in this compound, where a ferromagnetic cluster-glass behavior, ascribed to the anions network, and a spin crossover (SCO) of the [Fe(5–Cl-qsal)2]+ cations were observed. The glassy behavior, with a blocking temperature of ca. 7.5 K, results from the disorder in the anionic layer and the competition between ferro- and antiferromagnetic interactions in the anionic layers. The SCO process with T1/2 = 298 K (high spin fraction = γHS = 0.5) is rather sluggish in the limits of the conversion (γHS ∼ 0 and γHS ∼ 1), which is attributed to the effect of the anions that seem to restrict somehow the structural distortions of the cations associated with the SCO process.

A comparative benchmarking analysis of main Iberian container terminals: a DEA approach

Benchmarking is an important tool to organisations to improve their productivity, product quality, process efficiency or services. From Benchmarking the organisations could compare their performance with competitors and identify their strengths and weaknesses. This study intends to do a benchmarking analysis on the main Iberian Sea ports with a special focus on their container terminals efficiency. To attain this, the DEA (data envelopment analysis) is used since it is considered by several researchers as the most effective method to quantify a set of key performance indicators. In order to reach a more reliable diagnosis tool the DEA is used together with the data mining in comparing the sea ports operational data of container terminals during 2007. Taking into account that sea ports are global logistics networks the performance evaluation is essential to an effective decision making in order to improve their efficiency and, therefore, their competitiveness.

Multistability in a family of DT–TTF organic radical based compounds (DT–TTF)4[M(L)2]3 (M = Au, Cu; L = pds, pdt, bdt)

The preparation of new charge transfer salts based on the DT–TTF donor and monoanionic square planar transition metal bisdichalcogenide complexes M(L)2 (M = Au, Cu; L = pds, pdt, bdt, where pds = pyrazine-1,2-diselenolate, pdt = pyrazine-1,2-dithiolate, bdt = benzene-1,2-dithiolate) are reported and these salts are characterized by X-ray diffraction, EPR spectroscopy, electrical conductivity, thermoelectric power and static magnetization measurements, as well as tight-binding band structure calculations. Three compounds, (DT–TTF)4[AuIII(bdt)2]3, (DT–TTF)4[CuIII(pds)2]3, (DT–TTF)4[CuIII(pdt)2]3, are members of a general family of compounds of DT–TTF with stoichiometry 4 : 3 as the previously reported (DT–TTF)4[AuIII(pds)2]3. Although not strictly isostructural, all members of this family present a similar crystal packing motif of the donor and acceptor units and present a common pattern of first- and second-order phase transitions as seen in electrical transport and magnetic properties. The second-order phase transition is ascribed to a variation from dynamic to static charge ordering. With [CuIII(pdt)2] and DT–TTF a 1 : 1 salt with formula (DT–TTF)[CuIII(pdt)2] was also obtained. The structural differences and similarities between the four compounds (DT–TTF)4[M(L)2]3 (M = Au, Cu; L = pds, pdt, bdt), that are related to their physical properties, and the reversible phase transitions observed are discussed.

Novel Cu(III) bis-1,2-diselenolene complex with a highly extended 3D framework through Na+ coordination

The crystal structure of a new Cu(III) complex with the ligand pds2− (pds, pyrazine-2,3-diselenolate) shows a unique packing pattern with segregated stacks of complex molecules interconnected through the pyrazine N coordination to Na counterions, which complete their coordination environment with four water molecules.

Complexity as interdependence in input – output systems

In this paper we propose a new index of connectedness for an input–output system which is considered useful for quantifying economic complexity as the level of interdependence between the component parts (sectors) of a national (or regional) economy. This index is empirically applied in a tentative answer to the following questions: Should we expect to find a natural shift towards greater complexity as an economy grows and develops? Is a larger economy necessarily more complex than a smaller one? The interindustry tables of several OECD countries provide the material support for making international and historical comparisons of economic complexity as a level of interrelatedness.

2D Layered coordination polymer based on an unusual mixed valence Cu(III)/Cu(I) bis-1,2-diselenolene compound

The crystal structure of a new mixed-valence Cu(III)/Cu(I) compound containing the ligand pds2− (pds, pyrazine-2,3-diselenolate) shows a unique packing pattern with 2D layers formed by the coordination of the Cu(I) countercations to both the pyrazine N and Se atoms of the [CuIII(pds)2]− complex, with a distorted square pyramidal environment for Cu(I) centres.

Agents with emotional intelligence for storytelling

One core aspect of engaging narratives is the existence and development of social relations between the characters. However, creating agents for interactive storytelling and making them to be perceived as a close friend or a hated enemy by an user is an hard task. This paper addresses the problem of creating autonomous agents capable of establishing social relations with others in an interactive narrative. We present an innovative approach by looking at emotional intelligence and in particular to the skills of understanding and regulating emotions in others. To that end we propose a model for an agent architecture that has an explicit model of Social Relations and a Theory of Mind about others, and is able to plan about emotions of others and perform interpersonal emotion regulation in order to dynamically create relations with others. Some sample scenario are presented in order to illustrate the type of behaviour achieved by the model and the creation of social relations.

Magnetic and electrical properties of (DT-TTF)4[Au(pds)2]3

Abstract The charge transfer salt (DT-TTF) 4 [Au(pds) 2 ] 3 (DT-TTF, Δ 2,2′ -bithieno[3,4-d]-1,3-dithiol; pds, pyrazine-2,3-diselenate) was prepared and characterised by X-ray diffraction, electrical conductivity, thermoelectric power, magnetic susceptibility and EPR measurements. This compound crystallises in the triclinic system, space group P 1 , with the unit cell parameters a =9.712(5) A, b =13.620(5) A, c =17.169(5) A, α =97.254(5)°, β =106.132(5)°, γ =95.956(5)°, V =2141.10(15) A 3 , Z =1. Its crystal structure consists of a bidimensional network of DT-TTF tetramers and orthogonal anions. The electrical properties indicate it is a small gap semiconductor (2Δ=190 meV), with a room temperature conductivity of σ RT =2 S cm −1 . The electrical and magnetic properties reveal two types of transitions occurring upon cooling. The first, at 238 K, as a second order change to a large gap semiconducting state and, a lower transition, of first order type, with a large hysteresis between 210 and 150 K, probably associated with a larger structural change in the DT-TTF network.