SUSIG: an on-line signature database, associated protocols and benchmark results

We present a new online signature database (SUSIG). The database consists of two parts that are collected using different pressure-sensitive tablets ( one with and the other without an LCD display). A total of 100 people contributed to each part, resulting in a database of more than 3,000 genuine signatures and 2,000 skilled forgeries. The genuine signatures in the database are real signatures of the contributors. In collecting skilled forgeries, forgers were shown the signing process on the monitor and were given a chance to practice. Furthermore, for a subset of the forgeries ( highly skilled forgeries), this animation was mapped onto the LCD screen of the tablet so that the forgers could trace over the mapped signature. Forgers in this group were also informed of how close they were to the reference signature, so that they could improve their forgery quality. We describe the signature acquisition process and several verification protocols for this database. We also report the performance of a state-of-the-art signature verification system using the associated protocols. The results show that the highly skilled forgery set is significantly more difficult compared to the skilled forgery set, providing researchers with challenging forgeries. The database is available through http://icproxy.sabanciuniv.edu:215

Influence of diesel surrogates on the behavior of simplified spray models

Numerous experimental investigations make use of diesel surrogates to make the computational time reasonable. In the few studies where measured (surrogate and real diesel) and computed (surrogate only) results have been compared, the selection methodology for the surrogate constituent compounds and the measures taken to validate the chemical kinetic models are not discussed, and the range of operating conditions used is often small. Additionally, most simplified models use tuning variables to fit model results to measurements. This work makes the comparison between some frequently used diesel surrogates using a simple 1D vaporizing spray model, with the spray cone angle as the tuning parameter. Results show that liquid length and fuel fraction strongly depend on the physical properties of the used fuel for a fixed spray angle. These parameters are important for modeling auto-ignition and pollutant formation. The spray angle is varied till the spray length is the same for each surrogate. Results show important differences between other spray parameters such as local mixture fraction and axial velocity

A simple method to account for topography in the radiometric correction of radar imagery

This article presents a method that allows to study and correct the radiometric distortions caused by topography in SAR images. The method is easy to implement, and requires neither sophisticated software nor code-level programming. It also considers the case of a flat surface having an elevation different from the one for which calibration parameters were derived. An ortho-image of the slant range distance is used with a digital elevation model to generate images of the local incident angle along the range and azimuth directions. The method compensates for variations in the terrain area of each pixel and for the angular dependence of backscatter, allowing the choice of either an empirical or semi- empirical scattering model. The method is applied to high-resolution C-SAR subsets of an agricultural area in the Central Cordillera of Costa Rica. The removal of topographic features appears excellent for local incident angles up to 80 degrees, but small-scale structures have pronounced effects on the radar return for higher local incident angles and are not adequately corrected

Evaluation de la capacité de complexation des eaux naturelles de la rivière Saguenay, Canada

La rivière Saguenay est un affluent majeur du fleuve Saint-Laurent, Québec, Canada. La rivière Saguenay draine une région très industrialisée et se divise en deux sections : la section supérieure est peu profonde et constituée d'eau douce, tandis que la section en aval renferme un fjord profond caractérisé par une thermohalocline à environ 25 m. Nous avons caractérisé la capacité de complexation (CC) et la constante de stabilité critique (CSC) de ses eaux douces, dans la section supérieure de la rivière. Cinq différentes stations ont été échantillonnées le même jour; ces échantillons ont été fractionnés en fonction de la masse moléculaire nominale (NMM) des ligands dissous à l'aide de quatre colonnes de chromatographie par perméation de gel (GPC) Séphadex G-10, G-15, G-25 et G-50 utilisées en série. Pour les échantillons globaux, la CC diminue d'amont en aval passant de 0,32 à 0,14 µM. Nous n'avons pu identifier la cause de cette diminution qui pourrait être un simple effet de dilution ou une augmentation d'ions métalliques en solution. Une fois fractionnés, nous trouvons que la CC augmente avec NMM; par contre, la CC normalisée par unité de carbone est plus grande pour les ligands de plus faible NMM. Les CSC obtenues sont toutes similaires, environ 5 x 107 L mol-1, sauf pour les ligands ayant une NMM entre 700 et 1 800 g mol-1 avec une CSC de 27 x 107 L mol-1.The Saguenay River is a major affluent of the St. Lawrence River, Quebec, Canada. The Saguenay River which drains a heavily industrialized region can be subdivided into two sections: the upper section is rather shallow and contains freshwater as the lower one is a deep fjord characterized by a thermohalocline at about 25 m. This work aimed at identifying the possible modifications brought up by anthropogenic sources upon the complexation capacity of the freshwater of this River. Five different stations were sampled for surface water the same day on the upper section of the River. The samples were filtered on 0,4 µm membrane (pre-cleaned with HNO3). A portion was analyzed and other ones were fractionnated as a function of the nominal molecular mass (NMM) of dissolved ligands by using in series four gel permeation chromatographic (GPC) columns filled with Sephadex G-10, G-15, G-25 and G-50 respectively, the elution being dope by purified 18MOhms water. The complexation capacity (CC) and critical stability constant (CSC) of the different fractions have been characterized using a method based on free Cu2+ back-titration by Differential Pulsed Anodic Stripping Voltammetry (DPASV) and a 1:1 complexation scheme. Because copper was giving two unresolved peaks on the tailing of the oxygen peak, all polarograms have been deconvolved by a PASCAL computer program based on a least-sqares nonlinear fit using the Taylor differential correction technique. All results compiled were from the peak centered at - 60 mV against an Ag/AgCl reference. By manipulating the usual equations to determine CC and CSC with the free Cu2+ back-titration, we were able to calculate CC by three different routes and CSC by two different routes ; when enough reliable data were available for each route, all values obtained were concordant. So we observed that, going downstream, the CC decreased from 0,32 to 0,14 µM for whole samples. At this point, we cannot identity the cause of this decrease wether it is due to simple dilution or by addition of new dissolved metallic ions into the stream. Once fractionnated, CC measured was seen increasing with NMM but normalized CC per unit of carbon has been found to be greater for ligands with small NMM (normalized CC decreased with increasing NMM). The CSC obtained were all similar, about 5 x 107 L mol-1, excepted for ligands with NMM between 700 and 1 800 g mol-1, the CSC being 27 x 107 L mol-1 from the inverse linearized method

Sistema de Balanço Hídrico: manual do desenvolvedor.

O Sistema Balanço Hídrico, elaborado pela Unidade, completa o Sistema AgroCast desenvolvido e divulgado pela Agência Estado. O AgroCast disponibiliza diversas informações para o AgroNegócio, como commodities, previsão de tempo, taxas etc. Já o sistema desenvolvido pela Unidade, disponibiliza na internet dados sobre o Balanço Hídrico para diversos estados de São Paulo, com a possibilidade de gerar dados especificamente para os tipos de solos existente na região.bitstream/item/116952/1/898.PD

Manual do Sistema Balanço Hídrico e Calendário Agrícola.

Manual do Sistema Balanço Hídrico; Explicação e observações sobre os termos empregados nas tabelas do Balanço Hídrico; Modelo Entidade Relacionamento (MER); Objetivo operacional do sistema; Diferenciamento das duas maneiras de processamento do sistema; Funcionamento; Módulo arquivos; Módulo Balanço Hídrico; Módulo Utilitário; Módulo Sobre.bitstream/item/116808/1/834.pd

Imaging of a vibrating object by Sideband Digital Holography

We obtain quantitative measurements of the oscillation amplitude of vibrating objects by using sideband digital holography. The frequency sidebands on the light scattered by the object, shifted by n times the vibration frequency, are selectively detected by heterodyne holography, and images of the object are calculated for different orders n. Orders up to n=120 have been observed, allowing the measurement of amplitudes of oscillation that are significantly larger than the optical wavelength. Using the positions of the zeros of intensity for each value of n, we reconstruct the shape of vibration the object.Comment: 6 page

Online fabrication and characterization of capsule populations with a flow-focusing microfluidic system

This paper was presented at the 3rd Micro and Nano Flows Conference (MNF2011), which was held at the Makedonia Palace Hotel, Thessaloniki in Greece. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, Aristotle University of Thessaloniki, University of Thessaly, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute.We have designed a microfluidic system that combines a double flow-focusing setup for calibrated capsule fabrication with a microchannel for the characterization of their mechanical properties. The double flow-focusing system consists of a first Y junction to create the microdroplets and of a second Y junction to introduce the cross-linking agent allowing the membrane formation. The human serum albumin (HSA) aqueous solution for the dispersed solution, hydrophobic phase for the continuous solution and cross-linking agent solution are introduced by means of syringe pumps. A wavy channel after the second junction allows to control the reticulation time. A cylindrical microchannel then enables to deform and characterize the capsules formed. The mechanical properties of the capsule membrane are obtained by inverse analysis (Chu et al. 2011). The results show that the drop size increases with the flow rate ratio between the central and lateral channels and does not change much regardless of the flow rate of the reticulation phase. The mean shear modulus of the capsules fabricated after 23 s of reticulation is of the order of the surface tension of HSA solution with Dragoxat indicating that the reticulation time is too short to form an elastic membrane around the droplet. When the reticulation time is increased to 60 s, the membrane shear modulus is multiplied by a factor of 3 confirming that a solid membrane has formed around the drop