The application of wave induced forces to a two-dimensional finite element long wave hydrodynamic model

This paper describes the modification of a two-dimensional finite element long wave hydrodynamic model in order to predict the net current and water levels attributable to the influences of waves. Tests examine the effects of the application of wave induced forces, including comparisons to a physical experiment. An example of a real river system is presented with comparisons to measured data, which demonstrate the importance of simulating the combined effects of tides and waves upon hydrodynamic behavior. (C) 2002 Elsevier Science Ltd. All rights reserved.

Influence of leaf retention on cutting propagation of Lavandula dentata L.

Vegetative propagation of lavender offers several advantages over sexual propagation, among them crop homogeneity and yield of higher quality essential oil. However, Lavandula species have been propagated mostly by seeds and are said to be recalcitrant to rooting when propagated by cuttings. During cutting propagation, one of the important variables that influence the rooting capacity of cuttings is the leaf retention. The objective of this work was to evaluate the influence of leaf retention on rooting of L. dentata cuttings. Apical cuttings of L. dentata of 10 cm in length, keeping approximately 1/3, 1/2 or 2/3 of their leaves were planted in commercial substrate Plantmax HT® under intermittent mist. After two months, averages of root number, length of the longest root, root fresh and dry weights, and the survival percentage were evaluated. Root length and fresh weight were statistically greater with 2/3 of leaf retention and when fewer leaves were kept on the cuttings, lower means of root dry weight was observed. Under the conditions applied in this study, greater leaf retention was better for rooting of L. dentata cuttings.

Chemical sterilization in in vitro propagation of Arundina bambusifolia Lindl. and Epidendrum ibaguense Kunth

There is a great demand for simpler and less costly laboratory techniques and for more accessible procedures for orchid breeders who do not have the necessary theoretical basis to use the traditional seed and clone production methods of orchids in vitro. The aim of this study was to assess the use of sodium hypochlorite (NaClO) as a decontaminant in the process of inoculating adult orchid explants of Arundina bambusifolia and Epidendrum ibaguenses. Solutions of NaClO (1.200, 2.400, 3.600, 4.800 and 6.000 mg L-1 - equivalent to 50, 100, 150, 200 and 250 mL L-1 of commercial bleach - CB) were sprayed on the explants (1.0 mL) and the culture medium (GB5), in the presence or absence of activated charcoal (2 g L-1). The explants used were nodal segments of field-grown adult plants. The procedures for inoculating the explants were conducted outside the laminar flow chamber (LFC), except for the control treatment (autoclaved medium and explant inoculation inside the LFC). The best results for fresh weight yield, height and number of shoots were obtained using NaClO in solution at 1.200 mg L-1 (equivalent to 50 mL L-1 commercial bleach) with activated charcoal in the culture medium. Fresh weight figures were 1.10 g/jar for Arundina bambusifolia and 0.16 g/jar for Epidendrum ibaguenses. Spraying the NaClO solutions controls the contamination of the culture medium already inoculated with the explants.

Rooting of hardwood cuttings of Roxo de Valinhos fig (Ficus carica L.) with different propagation strategies

The objective of this study was to evaluate the substrate, cuttings collection time, the position and the cutting depth, and the propagation environment on rooting of 'Purple Valinhos' fig tree cuttings in Southwestern Paraná, Brazil. Two experiments were carried out at UTFPR, Câmpus Dois Vizinhos, with hardwoods cuttings from Roxo de Valinhos fig tree. The first experiment used a randomized block design, in 3 x 3 x 2 factorial (substrate x environment x collection time), with four replications of 10 cuttings per plot. The cuttings were collected in the first fifteen days of July and August. The substrates were sand, soil and the mixture of these [1:1 (v / v)]. The environments used were open sky, tunnel with plastic cover and tunnel with half-shade black net cover. The second experiment used a randomized block design, 2 x 2 x 3 factorial (shoot cutting position x soil cover x shoot cutting depth), with four replications of 12 cuttings per plot. In the factor position, the vertically (0 º inclination) and inclined (45 º inclination) shoot cuttings were evaluated. Soil cover was tested with mulching plastic cover or not. The tested depths were 1/3, 1/2 and 2/3 in relation to the total length of the shoot cutting. In both experiments, the following were analyzed: rooting and mortality indices, number of leaves and primary shoots, length of the three largest roots per cutting. It was conclude that, the protected environment with plastic cover on sand as substrate must recommended for the rooting of fig estaca, collecting them in the first half of July. The inclination position and cutting depth of the estaca and the substrate coverage with plastic mulching did not influence the results.

Performance of coastal sea-defense infrastructure at El Jadida (Morocco) against tsunami threat: lessons learned from the Japanese 11 March 2011 tsunami

This paper seeks to investigate the effectiveness of sea-defense structures in preventing/reducing the tsunami overtopping as well as evaluating the resulting tsunami impact at El Jadida, Morocco. Different tsunami wave conditions are generated by considering various earthquake scenarios of magnitudes ranging from M-w = 8.0 to M-w = 8.6. These scenarios represent the main active earthquake faults in the SW Iberia margin and are consistent with two past events that generated tsunamis along the Atlantic coast of Morocco. The behavior of incident tsunami waves when interacting with coastal infrastructures is analyzed on the basis of numerical simulations of near-shore tsunami waves' propagation. Tsunami impact at the affected site is assessed through computing inundation and current velocity using a high-resolution digital terrain model that incorporates bathymetric, topographic and coastal structures data. Results, in terms of near-shore tsunami propagation snapshots, waves' interaction with coastal barriers, and spatial distributions of flow depths and speeds, are presented and discussed in light of what was observed during the 2011 Tohoku-oki tsunami. Predicted results show different levels of impact that different tsunami wave conditions could generate in the region. Existing coastal barriers around the El Jadida harbour succeeded in reflecting relatively small waves generated by some scenarios, but failed in preventing the overtopping caused by waves from others. Considering the scenario highly impacting the El Jadida coast, significant inundations are computed at the sandy beach and unprotected areas. The modeled dramatic tsunami impact in the region shows the need for additional tsunami standards not only for sea-defense structures but also for the coastal dwellings and houses to provide potential in-place evacuation.

Aplicações e algoritmos de segurança rodoviária com o uso de sistemas de GPS e de comunicações WAVE

Trabalho Final de Mestrado para obtenção do grau de Mestre em Engenharia de Electrónica e Telecomunicações

Square-wave voltametric method for determination of molinate concentration in a biological process using a hanging mercury drop electrode

A square-wave voltammetric (SWV) method using a hanging mercury drop electrode (HMDE) has been developed for determination of the herbicide molinate in a biodegradation process. The method is based on controlled adsorptive accumulation of molinate for 10 s at a potential of -0.8 V versus AgCl/Ag. An anodic peak, due to oxidation of the adsorbed pesticide, was observed in the cyclic voltammogram at ca. -0.320 V versus AgCl/Ag; a very small cathodic peak was also detected. The SWV calibration plot was established to be linear in the range 5.0x10-6 to 9.0x10-6 mol L-1; this corresponded to a detection limit of 3.5x10-8 mol L-1. This electroanalytical method was used to monitor the decrease of molinate concentration in river waters along a biodegradation process using a bacterial mixed culture. The results achieved with this voltammetric method were compared with those obtained by use of a chromatographic method (HPLC–UV) and no significant statistical differences were observed.

Square-wave adsorptive-stripping voltammetric detection in the quality control of fluoxetine

Electroanalytical methods based on square-wave adsorptive-stripping voltammetry (SWAdSV) and flow-injection analysis with square-wave adsorptive-stripping voltammetric detection (FIA-SWAdSV) were developed for the determination of fluoxetine (FXT). The methods were based on the reduction of FXT at a mercury drop electrode at -1.2 V versus Ag/AgCl, in a phosphate buffer of pH 12.0, and on the possibility of accumulating the compound at the electrode surface. The SWAdSV method was successfully applied in the quantification of FXT in pharmaceutical products, human serum samples, and in drug dissolution studies. Because the presence of dissolved oxygen did not interfere significantly with the analysis, it was possible to quantify FXT in several pharmaceutical products using FIA-SWAdSV. This method enables analysis of up to 120 samples per hour at reduced costs.

Local fractional variational iteration and decomposition methods for wave equation on cantor sets within local fractional operators

We perform a comparison between the fractional iteration and decomposition methods applied to the wave equation on Cantor set. The operators are taken in the local sense. The results illustrate the significant features of the two methods which are both very effective and straightforward for solving the differential equations with local fractional derivative.

Incorporação de resíduo da indústria petrolífera em argamassas de cal hidráulica para a reabilitação de edifícios

Trabalho Final de Mestrado para obtenção do grau de Mestre em Engenharia Civil na Área de Especialização de Edificações

From local to global importance measures of uncertainty propagation in composite structures

The influence of uncertainties of input parameters on output response of composite structures is investigated in this paper. In particular, the effects of deviations in mechanical properties, ply angles, ply thickness and on applied loads are studied. The uncertainty propagation and the importance measure of input parameters are analysed using three different approaches: a first-order local method, a Global Sensitivity Analysis (GSA) supported by a variance-based method and an extension of local variance to estimate the global variance over the domain of inputs. Sample results are shown for a shell composite laminated structure built with different composite systems including multi-materials. The importance measures of input parameters on structural response based on numerical results are established and discussed as a function of the anisotropy of composite materials. Needs for global variance methods are discussed by comparing the results obtained from different proposed methodologies. The objective of this paper is to contribute for the use of GSA techniques together with low expensive local importance measures.

Uncertainty propagation in inverse reliability-based design of composite structures

An approach for the analysis of uncertainty propagation in reliability-based design optimization of composite laminate structures is presented. Using the Uniform Design Method (UDM), a set of design points is generated over a domain centered on the mean reference values of the random variables. A methodology based on inverse optimal design of composite structures to achieve a specified reliability level is proposed, and the corresponding maximum load is outlined as a function of ply angle. Using the generated UDM design points as input/output patterns, an Artificial Neural Network (ANN) is developed based on an evolutionary learning process. Then, a Monte Carlo simulation using ANN development is performed to simulate the behavior of the critical Tsai number, structural reliability index, and their relative sensitivities as a function of the ply angle of laminates. The results are generated for uniformly distributed random variables on a domain centered on mean values. The statistical analysis of the results enables the study of the variability of the reliability index and its sensitivity relative to the ply angle. Numerical examples showing the utility of the approach for robust design of angle-ply laminates are presented.

A VLF to UHF propagation model for evaluation of high-speed railway electromagnetic interference in RF monitoring base-stations

Considering that recent european high-speed railway system has a traction power system of kV 50 Hz, which causes electromagnetic emission for the outside world, it is important to dimension the railway system emissions, using a frequency/distance dependent propagation model. This paper presents an enhanced theoretical model for VLF to UHF propagation, railway system oriented. It introduces the near field approach (crucial in low frequency propagation) and also considers the source characteristics and type of measuring antenna. Simulations are presented, and comparisons are set with earlier far field models. Using the developed model, a real case study was performed in partnership with Refer Telecom (portuguese telecom operator for railways). The new propagation model was used in order to predict the future high-speed railway electromagnetic emissions in the Lisbon north track. The results show the model's prediction capabilities and also its applicability to realistic scenarios.

Travelling wave profiles in some models with nonlinear diffusion

We study some properties of the monotone solutions of the boundary value problem (p(u'))' - cu' + f(u) = 0, u(-infinity) = 0, u(+infinity) = 1, where f is a continuous function, positive in (0, 1) and taking the value zero at 0 and 1, and P may be an increasing homeomorphism of (0, 1) or (0, +infinity) onto [0, +infinity). This problem arises when we look for travelling waves for the reaction diffusion equation partial derivative u/partial derivative t = partial derivative/partial derivative x [p(partial derivative u/partial derivative x)] + f(u) with the parameter c representing the wave speed. A possible model for the nonlinear diffusion is the relativistic curvature operator p(nu)= nu/root 1-nu(2). The same ideas apply when P is given by the one- dimensional p- Laplacian P(v) = |v|(p-2)v. In this case, an advection term is also considered. We show that, as for the classical Fisher- Kolmogorov- Petrovski- Piskounov equations, there is an interval of admissible speeds c and we give characterisations of the critical speed c. We also present some examples of exact solutions. (C) 2014 Elsevier Inc. All rights reserved.

Halting the fuse discharge propagation using optical fiber microwires

We report and analyze the halting of the fuse effect propagation in optical fiber microwires. The increase of the mode field diameter in the tapered region decreases the optical intensity resulting in the extinction of the fuse effect. This fiber element presents a low insertion loss and can be introduced in the optical network in order to protect the active equipment from the damage caused by the fuse effect.