Mytilene E-guide: a multiplatform mobile application tourist guide exemplar

This paper introduces an approach of enhancing the tourism experience by incorporating a tool that adopts a “web-to-mobile” model into tourism websites that allows for the adaptation of personalized tourism web content to be transferred to a mobile application hosted at users’ mobile device. These applications upon installation to mobile devices allow for browsing of adapted multimedia content with no requirement for constant network connection. Furthermore so we convey the development experiences of a multiplatform mobile tourist guide aimed at producing a personalized mobile guide application used in both an online and offline modes offering services to tourists such as a personal profiling-based recommendation system, a commenting system and location-based services. This paper focuses on the design, implementation and usability case study of a Multi-Platform Tourist Guide system for the Municipal Council of Mytilene, Greece.     

Protein immobilization on carbon nanotubes through a molecular adapter

A new approach to the modification of carbon nanotubes with biomolecules for the development of nanoscale biosensors is presented. Alkaline phosphatase was immobilized on the surface of multi-wall carbon nanotubes utilizing a layer-by-layer methodology. Carbon nanotubes were incubated with streptavidin, resulting in the formation of a protein layer on the surface of the nanotubes. Biotinylated alkaline phosphatase was then allowed to bind to streptavidin, anchoring the sensing protein onto the surface. Electrochemical biosensors were constructed by using carbon nanotubes compacted into pellets. 1-Naphthyl phosphate, which is hydrolyzed by alkaline phosphatase to the electroactive 1-naphthol, was used as a substrate. Electrodes constructed in this manner were observed to generate an electrochemical signal that was a function of substrate concentration.     

Poly(amino acid)-facilitated electrochemical growth of metal nanoparticles

Poly(amino acids) are natural chelating agents for various metal ions. Zinc ions were encapsulated in situ in a conductive polypyrrole film using polyglutamic acid as a localized complexing agent within the film. The subsequent electrochemical reduction of the metal ions to zero-valent metal leads to the formation of the nanoparticles. The electrochemical approach demonstrated in this report provides facile regeneration of the particles and also prevents aggregation of nanoparticles in the conductive polymeric film. The correlation of the amount of zinc with the thickness of the film indicates that the zinc resides largely in the outer layer of the film. TEM and EDS data show that the nanoparticles formed are composed of zinc and are 18 +/- 7 nm in diameter. The nanoparticle/ polymer composite was used to reduce halogenated organics, indicating its potential usefulness in remediation applications.     

Determination of the structures of small gold clusters on stepped magnesia by density functional calculations

The structural modifications of small supported gold clusters caused by realistic surface defects (steps) in the MgO(001) support are investigated by computational methods. The most stable gold cluster structures on a stepped MgO(001) surface are searched for in the size range up to 24 Au atoms, and locally optimized by density-functional calculations. Several structural motifs are found within energy differences of 1 eV: inclined leaflets, arched leaflets, pyramidal hollow cages and compact structures. We show that the interaction with the step clearly modifies the structures with respect to adsorption on the flat defect-free surface. We find that leaflet structures clearly dominate for smaller sizes. These leaflets are either inclined and quasi-horizontal, or arched, at variance with the case of the flat surface in which vertical leaflets prevail. With increasing cluster size pyramidal hollow cages begin to compete against leaflet structures. Cage structures become more and more favourable as size increases. The only exception is size 20, at which the tetrahedron is found as the most stable isomer. This tetrahedron is however quite distorted. The comparison of two different exchange-correlation functionals (Perdew-Burke-Ernzerhof and local density approximation) show the same qualitative trends.     

A SIMPLIFIED DESCRIPTION OF CHAR COMBUSTION

A simplified analysis of carbonaceous particle combustion is presented that includes the effects of pore diffusion and growth as well as gas-phase heat and mass transfer. The combustion dynamics are described by time-dependent equations for particle temperature, radius and a number of intraparticle conversion variables. These are coupled to pseudosteady equations for gas-phase transport and internal reaction and diffusion. The differential equations for gas-phase transport are reduced by quadrature to a nonlinear boundary condition to the intraparticle boundary value problem. Numerical calculations are performed for conditions relevant to pulverized coal combustion. An analytical solution of the intraparticle problem, pertinent to the regime of strong diffusional limitations, reduces the intraparticle solution into a set of two quadratures which drastically simplifies the numerical calculations. The simplified intraparticle solution is in excellent agreement with the full solution at 1800 K free stream temperature and fair agreement at 1500 K.     

A kinetic model of membrane formation by CVD of SiO2 and Al2O3

Silica and alumina layers deposited onto the walls of porous Vycor tubes by chloride hydrolysis in an opposing reactants geometry have been characterized by scanning electron microscopy and electron microprobe analysis. The layers are asymmetric, having a long tail toward the side of the chloride flow and a sharp boundary at the other side. The deposit thickness is several tenths of microns, while the totally plugged region is of order of 1 micron. A model has been developed describing reaction, diffusion and evolution of the porous structure in the Vycor substrate due to the accumulation of the solid product. The deposition reaction is described by transient kinetics in terms if the concentrations of silanol and chloride groups in the product layer, as well as the concentrations of the gaseous reactants. The model is capable of generating deposit profiles in good agreement with those measured by electron microprobe analysis.     

Electronic mobile guides: a survey

Mobile tourist guides have been in the spot light for the past decade and are becoming increasingly available in various forms to tourists visiting places. The majority of these mobile tourist guides are to be used via a constant network connection and some as proprietary standalone mobile applications installed on-device. Some are solely navigational assistants using positioning technologies for large cities offering exploratory services and others are used indoors, for example as museum guides. This research paper attempts to categorize these mobile guides using a detailed set of evaluation criteria in order to extract design principles which can be used by application designers and developers.     

Occlusion handling in outdoors augmented reality games

Multimedia Tools and Applications - The use of augmented reality (AR) becomes increasingly common in mobile game development as a means of enhancing the players’ view of the physical world...