Dimensionality Reduction and Classification feature using Mutual Information applied to Hyperspectral Images : A Filter strategy based algorithm

Hyperspectral images (HIS) classification is a high technical remote sensing tool. The goal is to reproduce a thematic map that will be compared with a reference ground truth map (GT), constructed by expecting the region. The HIS contains more than a hundred bidirectional measures, called bands (or simply images), of the same region. They are taken at juxtaposed frequencies. Unfortunately, some bands contain redundant information, others are affected by the noise, and the high dimensionality of features made the accuracy of classification lower. The problematic is how to find the good bands to classify the pixels of regions. Some methods use Mutual Information (MI) and threshold, to select relevant bands, without treatment of redundancy. Others control and eliminate redundancy by selecting the band top ranking the MI, and if its neighbors have sensibly the same MI with the GT, they will be considered redundant and so discarded. This is the most inconvenient of this method, because this avoids the advantage of hyperspectral images: some precious information can be discarded. In this paper we'll accept the useful redundancy. A band contains useful redundancy if it contributes to produce an estimated reference map that has higher MI with the GT.nTo control redundancy, we introduce a complementary threshold added to last value of MI. This process is a Filter strategy; it gets a better performance of classification accuracy and not expensive, but less preferment than Wrapper strategy.Comment: 11 pages, 5 figures, journal pape

DEMOCRACY AND CITIZENSHIP IN NORTH AFRICA AFTER THE ARAB AWAKENING: CHALLENGES FOR EU AND US FOREIGN POLICY (EUSPRING). Arab Citizenship Review No. 3, Tunisia, August 2013

This series of policy briefs provides a regular update of debates concerning key rights issues in three Arab states, Morocco, Egypt and Tunisia. In a first round of briefs on the three countries, we provide background on these debates since the beginning of the Arab spring

Reflexiones sobre la revolución tunecina

El régimen del presidente tunecino Zine El Abidine Ben Ali se vino abajo tras apenas un mes de protestas públicas sin precedentes. El devenir del país dependerá de las decisiones del gobierno interino. El inesperado desarrollo de la revuelta popular tunecina que ha apeado del poder al presidente Ben Ali tras 23 años al mando ha respondido a una serie de factores que son específicos al país. El devenir del país dependerá de las decisiones del gobierno interino. Pese a sus distintas posiciones, los implicados deberán encontrar un terreno común que les permita alcanzar un equilibrio. Los aliados del ayer competirán mañana en las urnas. Desafortunadamente, el diálogo escasea y persiste el interrogante respecto del futuro papel de las fuerzas armadas, si bien no puede descartarse un aumento del apoyo a los islamistas. Dado que la revolución tunecina es la primera de este tipo en el mundo árabe –un levantamiento popular que ha logrado con éxito expulsar a un dictador–, es razonable preguntarse si seguirán su ejemplo los países vecinos. El riesgo de contagio es significativo, aunque ni es inevitable ni debe esperarse una replicación idéntica en otros países

Non-additive Lie centralizer of strictly upper triangular matrices

Let ℱ be a field of zero characteristic, let Nn(ℱ) denote the algebra of n X n strictly upper triangular matrices with entries in ℱ, and let ƒ : Nₙ(ℱ) → Nₙ(ℱ) be a non-additive Lie centralizer of Nₙ(ℱ), that is, a map satisfying that ƒ([X; Y ]) = [ƒ(X); Y ] for all X; Y ∈ Nₙ(ℱ). We prove that ƒ(X) = ⋋ X + ƞ (X) where ⋋ ∈ ℱ and ƞ is a map from Nₙ(ℱ) into its center Ƶ (Nₙ(F)) satisfying that ƞ([X; Y ]) = 0 for every X; Y in Nₙ(ℱ).peerReviewe

Citizenship in post-awakening Tunisia: power shifts and conflicting perceptions

With the passing of its new Constitution, Tunisia is rightly celebrated as the Arab state that has advanced the most in strengthening democratic rights provisions. The Constitution formally enshrines the progress Tunisia has made especially on women’s rights; the rights of expression and assembly; freedom of the press; the rights of political parties; and the formal recognition of social and economic rights. However, the Constitution does not definitively resolve tensions between individual and religious rights. In order to maintain consensus between the differing opinions in Tunisia, the document remains ambivalent on the state’s precise role in protecting the ‘sacred’. Tunisia has made much progress, but the Constitution is likely to perpetuate rather than close debates over different concepts of rights

Crystal structure of N,N,N',N'-tetramethylethylenediammonium dinitrate

N,N,N',N'-tetramethylethylenediammonium dinitrate has been synthesized. The crystal and molecular structure of the title compound has been determined from single crystal X-ray diffraction data. C6H18N4O6, M =242.24, Triclinic, a = 6.040(2) Å, b = 6.834(3) Å, c = 7.867(2) Å, α = 74.1120(10)°, β = 83.700(2)°, γ = 80.314(2)°, V = 307.12(19) Å3, T = 298(2) K, space group P-1 (no. 2), Z = 1, μ(Mo-Kα) = 0.115, 2383 reflections measured, 1342 unique (Rint = 0.0169) which were used in all calculations. The final wR(F2) was 0.1262 (all data). In the title compound, C6H18N22+.2NO3-, both N atoms of the cationic moiety are protonated and linked via hydrogen bonds to two trigonal planar nitrate anions. Two types of classical hydrogen bonds are observed: N1-H…O1 and N1-H…O2. These bonds link the cations and the anions together, forming a one-dimensional network and reinforcing the cohesion of the ionic structure