A hybrid approach to vehicle routing using neural networks and genetic algorithms

A competitive neural network model and a genetic algorithm are used to improve the initialization and construction phase of a parallel insertion heuristic for the vehicle routing problem with time windows. The neural network identifies seed customers that are distributed over the entire geographic area during the initialization phase, while the genetic algorithm finds good parameter settings in the route construction phase that follows. Computational results on a standard set of problems are also reported.     

Numerical modelling and implementation of ferrite cored eddy current probes

This paper focuses on the development of a magnetic moment method of calculating vector field quantities for a highly permeable ferrite cored eddy current probe. Basis functions are used in this method to replace the scattered field caused by the probe core in accordance with the surface equivalence theorem. These functions are further developed and tested for accuracy and convergence. An efficient material profile equation, independent of probe coil and basis function properties, is also designed and verified. Collocation point selection and optimisation is finally undertaken leading to the accurate determination of probe source coil impedance. The accuracy of calculation is verified using an industry standard finite element solver.     

Vacuum-deposited carbon coatings

In recent years, highly favorable results have been obtained using low temperature isotropic pyrolytic carbons in prosthetic devices requiring a high degree of thromboresistance. The development of vacuum-deposited carbon coatings was undertaken to extend the application of carbon to geometries and configurations that cannot be fabricated from low temperature isotropic carbon. Vacuum-deposited coatings have been produced on a variety of metallic and polymeric substrates.The different vacuum deposition processes which have been investigated include electron beam gun evaporation using high vacuum, gas scattering and ion- plating conditions. In addition, sputtering processes using ion beams and magnetically confined plasmas were studied.The surface morphology, structure and preferred orientation of the coatings produced by the different processes were characterized by scanning and transmission electron microscopy. Film purity and interfacial characteristics were examined by Auger electron spectroscopy.The scanning electron microscopy study shows that thin carbon films generally have a smooth and featureless surface morphology. However, other surface morphology features are obtained in thicker films, depending on the processing conditions. The transmission electron micrographs show the absence of structure and growth features. Electron diffraction indicates that the films consist of a turbostratic phase and a non-crystalline phase. The apparent crystallite sizes are small, and there is no three-dimensional ordering. Generally, the films are isotropic and consist of relatively pure carbon, with the degree of disorder dependent on the process conditions.     

Sensation seeking, augmenting-reducing, and absolute auditory threshold: A strength-of-the-nervous-system perspective.

Tested 40 male and female high school and college students on the General and the Disinhibition subscales of the Sensation Seeking Scale (Form IV), the Reducer-Augmenter Scale (RAS), and the absolute auditory threshold (AAT). General sensation seeking correlated significantly with the RAS and the AAT. Both results were general across sex. These findings, that high-sensation seekers tend to be reducers and to lack sensitivity to weak stimulation, are interpreted as supporting strength-of-the-nervous-system theory more than the formulation of M. Zuckerman et al (see record 1975-02479-001). (36 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of Surface Roughness on the Acid Etching of Amorphous Silica

The effect of the root-mean-square (rms) roughness on the acid etching of roughened amorphous silica was studied as a function of time using atomic force microscopy and laser light scattering. The initial size and distribution of micrometer-sized surface flaws are shown to influence the time evolution of the etching by hydrofluoric acid. The increase in the optical transparency of the samples is linked to the large increases in the correlation lengths of the sample surfaces, an effect which counteracts the accompanying rise in the rms roughness.     

Towards a re-programmable DNA computer

Microreactors lend themselves to a relatively simple implementation of DNA computing. Not only is the design of the DNA library critical for the success of the system but also the architecture of the microfluidic structure. Microreactors can be configured as Boolean operators. This paper will show that biomolecular computing can be performed with elementary building blocks, analogous to electronic logic gates. These logical operations will be performed using negative selection. Furthermore, an alternative bead barrier is introduced which can render the computer re-programmable and shows an principle architecture for selection and analysis.     

Best Linear Unbiased Estimator of the Parameter of the Rayleigh Distribution?Part II: Optimum Theory for Selected Order Statistics

The member of the class of best linear unbiased estimators (BLUEs) of a parameter based on k order statistics which has minimum variance is called the k-optimum BLUE. The ranks, coefficients, variance, and efficiency are given for the k-optimum BLUE of the parameter of the Rayleigh distribution for k = 2(1)4 and a sample size of N = 2(1)22. In addition, an approximate k-optimum BLUE is given for k = 2(1)4 and N ? 23.