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This note presents the application of the functional network (FN) and the sequential learning neural network (SLNN) for accurate prediction of tides during surge using short-term observation. Based on 34-day observed data, the proposed functional network model can predict the time series data of hourly tides directly, using an efficient learning process that minimizes the error. In the functional network, a simple equation in the form of a finite-difference equation is derived, using the tidal levels at two previous time steps. The sequential learning neural network uses one hidden neuron to predict the current tidal level. Hourly tidal data for the Typhoon Herb, measured at Taichung Harbor along the Taiwan coastal region, is used for testing the capacity of the functional network and sequential neural network models. Numerical results demonstrate that the proposed models can predict the tidal level during typhoon surge with a high correlation coefficient, based on 1-month hourly data. DOI: 10.1061/(ASCE)0733-950X(2005) 131:6(321) CE Database subject headings: Typhoons; Surge; Neural networks; Tidal water; Forecasting; Taiwan.

Grazing-incidence x-ray diffraction was used to study Si/Ge films grown by surfactant mediated molecular beam epitaxy on Si(001).

Ultrahigh vacuum/chemical vapor deposition system (UHV/CVD) facilitated the growth of high quality Si/Si(1-x)Ge(x) superlattices with 1.5 nanometer thin layers. X-ray diffraction and transmission electron microscopy were used to analyze the crystalline quality.

Conventional and high-resolution transmission electron microscopy, Auger electron spectroscopy and X-ray diffraction are used to study interfacial reactions that occur in ultrahigh vacuum deposited Y-Si multilayer thin films. Multilayers composed of YSi2 form a 65-nm-thick amorphous Y-Si intermixing layer at room temperature. Annealing of the samples at 250-350 degrees Celsius leads to homogenization of atomic composition, although the multilayer maintains its amorphous state.

The low-temperature behavior of ultrahigh vacuum deposited yttrium thin films on an atomically clean (111)Si substrate was investigated. Experiments were performed wherein yttrium thin films were deposited on an atomically clean, phosphorous-doped (111)Si substrate at room temperature. The profile of the resulting structure was then analyzed by high-resolution transmission electron microscopy. Results show that the thickness of the thin films is strongly dependent on the annealing time and temperature.

Conventional and high-resolution transmission electronmicroscopy were used to analyze the evolution of vacancy ordering and defect structure in epitaxial YSi thin films on Si. Epitaxial YSi 2-x were formed whensamples were annealed at 500 degrees celsius for 120 seconds. When the temperature reached 600 degrees celsius for a period of 15 seconds, an ordered vacancy superstructure was formed and additional diffraction spots appeared. Atthe same temperature but for longer periods, or at higher temperatures, an out-of-step structure was formed and the extra diffraction spots were split.

The formation of amorphous interlayers in yttrium thin films grown by ultrahigh vacuum deposition on (111)Si substrates was investigated. The results showed that the thickness of the amorphous interlayer increased with greater annealing times and temperatures. As the critical thickness was surpassed, further intermixing between Y and Si took place but was eventually superseded by crystalline phase formation.

The strain relaxation in SmNi[O.sub.3] epitaxial films deposited by chemical vapor deposition on SrTi[O.sub.3] substrates is studied. A phenomenological model is used for particular planar faults that give rise to extended diffuse scattering on transverse scans.

The rapid microstructural evolution of gas atomised Ni superalloy powder compacts over timescales of a few seconds was studied using a Gleeble 3500 thermomechanical simulator, finite element based numerical model and electron microscopy. The study found that the microstructural changes were governed by the characteristic temperatures of the alloy. At a temperature below the γ' solvus, the powders maintained dendritic structures. Above the γ' solvus temperature but in the solid-state, rapid grain spheroidisation and coarsening occurred, although the fine-scale microstructures were largely retained. Once the incipient melting temperature of the alloy was exceeded, microstructural change was rapid, and when the temperature was increased into the solid + liquid state, the powder compact partially melted and then re-solidified with no trace of the original structures, despite the fast timescales. The study reveals the relationship between short, severe thermal excursions and microstructural evolution in powder processed components, and gives guidance on the upper limit of temperature and time for powder-based processes if desirable fine-scale features of powders are to be preserved. [ABSTRACT FROM AUTHOR]

Describes the polarity of a 1 um thick GaN film grown by molecular beam epitaxy on an single crystal using the x-ray standing wave method. How the standing was generated from the GaN film; Qualities of noncentrosymmetric compound crystals; What perfect single crystals exhibit.

Neutron diffraction was used to characterize the residual stresses in an as-sprayed tube-shaped steel preform. The measured residual stress distributions were compared with those simulated using finite element method by taking into account the effects of the thermal history, porosity and different phases of the sprayed preform. The porosity was measured using X-ray microcomputed tomography. The study revealed for the first time the correlation between the distribution of porosity and residual stress developed in the as-sprayed preform. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synchrotron X-ray total scattering method was used to study tensile fractured surface of a metallic glass and a metallic glass composite. • A clear correlation was found between X-ray scattering structure factor and the shear band density. • The higher the shear band density, the higher the X-ray scattering structure factor. • Such correlation has the potential to be developed into a nondestructive method for measuring the residual shear band density for metallic glasses after deformation. The tensile fractured surfaces of ZrTi-based bulk metallic glass and composite samples were studied using synchrotron X-ray total scattering. The scanned areas contain different shear bands densities. The shear bands create localized atomic strains, which in turn cause more ordered atomic structures. Such structural changes were reflected in the scattering structure factor, i.e. the higher the density of the shear bands, the higher the scattering structure factor. Similar phenomenon was also found in the metallic glass composite. [ABSTRACT FROM AUTHOR]

Microalgae have the potential to become a novel source of bioactive molecules, especially for those who might wish to enhance the nutritional and functional quality of foods. Spirulina, one of the most popular microalgae, has been described by the World Health Organization as one of the greatest superfoods on earth serving as an example of the potential of microalgae. This review provides background on current and future uses of microalgae in the human diet, lists the most common species of microalgae used to this end, and describes some production methods used in research and industrial production and recovery. The review also discusses some of the difficulties so far encountered such as low productivities and recovery rates, as well as challenges in the production of compounds of interest. Many scientists and engineers in research centers around the globe are currently dedicated to solve these problems as the various capabilities of microalgae have caught the attention of the energy, environmental, and agricultural industries, we propose that the food industry should as well evaluate the potential of microalgae as a novel source of 'health promoting' compounds. [ABSTRACT FROM AUTHOR]

The mechanical performances of timber joints are particularly important for timber engineers involved in the design of the wood structures. In general, joints are often one of the weakest points in a timber structure. However, to simplify the problem, most previous investigations have considered the effects of individual parameters on the mechanical behavior of timber joints. Thus, it is difficult to undertake an analytical study due to interactions among parameters. In this paper, a finite element model for a dowel-type timber joint is proposed to investigate the mechanical performance of un-reinforced and reinforced timber joints affected by the various parameters. Moreover, a stress-interaction based failure criterion is proposed to predict the strength of such joints. The numerical prediction of the proposed finite element method model overall agrees with the experimental results of mechanical testing. [Copyright &y& Elsevier]

An accurate tidal forecast is an important task in determining constructions and human activities in ocean environments. Conventional tidal forecasting has been based on harmonic analysis using the least squares method to determine harmonic parameters. However, a large number of parameters are required for the prediction of a long-term tidal level with harmonic analysis. Unlike conventional harmonic analysis, this paper presents an artificial neural network (ANN) model for forecasting the tidal-level using the short term measuring data. The ANN model can easily decide the unknown parameters by learning the input–output interrelation of the short-term tidal records. Three field data with three types of tides will be used to test the performance of the proposed ANN model. The numerical results indicate that the hourly tidal levels over a long duration can be predicted using a short-term hourly tidal record. [Copyright &y& Elsevier]

• Bulk CoCrFeMnNi high entropy alloy was fabricated by laser melting deposition. • The residual stress distribution was characterized using ND and FEM. • Residual stress decreases along the building direction. The dynamic thermal history during the laser melting deposition (LMD) process can induce significant residual stress that can lead to distortion and deteriorate functionality. The residual stress distribution in a bulk CoCrFeMnNi high entropy alloy with a single FCC phase and the dendritic structure fabricated by LMD process was studied using neutron diffraction and finite element modelling to reveal the effects of the thermal constraints, thermal cycles and temperature gradient along the deposition direction. Residual stress was found to decrease as the thermal gradient decreases along the building direction in the LMD process. [ABSTRACT FROM AUTHOR]

Discusses the thermal annealing of 720 degrees Celsius for two hours with an SiO[sub 2]-capped layer after source/drain extensions implantation to improve the short channel characteristics of a 0.1-micrometer metal oxide semiconductor field-effect transistors. Influence and mechanism of the capped layer on the boron uphill treatment; Benefits of the capped layer treatment.

Examines the dopant distribution of the silicon delta-doped gallium arsenide by transmission electron spectroscopy. Observation of different silicon doses from half a monolayer to two monolayers; Indication of excellent confinement of dopants in gallium arsenide; Uniform distribution of silicon atoms in the doped layer.