Pedestrian-behavior-based mobile agent control in intelligent space

This paper investigates a human walking behavior-based mobile robot control system. The Intelligent Space (iSpace) is a distributed sensory system, which is the background infrastructure to observe human walking in a limited area. The observation of human walking behavior is applied to train fuzzy-neural networks (FNN). The trained FNNs are applied to approximate the obstacle avoidance behavior of human walking. The paper introduces the iSpace and the mobile agents, which are mobile robots, utilizing the intelligence of the iSpace. The observed and trained human walking behaviors are applied to control the mobile agent in a human-robot shared environment. Experimental results demonstrate the effectiveness of the FNN-based control system.     

TRADE‐OFF BETWEEN APPROXIMATION ACCURACY AND COMPLEXITY FOR TS FUZZY MODELS

This paper proposes a transformation method that serves the trade‐off between the modelling complexity and accuracy of multi‐variable Takagi‐Sugeno fuzzy inference operator‐based modelling (TS fuzzy modelling). The relation between the number of fuzzy rules and the modelling accuracy is defined in the paper. The proposed transformation method is capable of finding the minimal number of fuzzy rules for a given accuracy of a given TS fuzzy model. A case study, focusing on a benchmark problem of fault diagnosis, developed in the framework of EC‐founded Research Training Network DAMADICS, of an actuator in a sugar factory, is presented to provide feasibility of the proposed method.     

Three-dimensional analysis of the spatial distribution of iron oxide particles in a decorative coating by electron microscopic imaging

The three-dimensional (3D) spatial structure of an iron oxide containing alkyd paint specimen has been investigated by serial block-face scanning electron microscopy (SBFSEM). The resultant images of the 3D structure clearly present the spatial distribution of the iron oxide pigment particles in the coating film and reveal the extent of aggregation of the particles in the matrix material. More than one-half of the iron oxide particles (in volume) had aggregated to form clusters of considerable sizes that follow a Gaussian spacing distribution in the measured coating film. Over 80% of the clusters have dimensions between 1.5 μm and 3.5 μm; also, pores are evident at the centres of clusters whose sizes are larger than 2 μm. The work demonstrated here reveals a new approach to fully characterize the 3D spatial structure of coatings and to explore their correlations with the performance of the materials.     

Sustained photobiological hydrogen production in the presence of N2 by nitrogenase mutants of the heterocyst-forming cyanobacterium Anabaena

Heterocyst-forming cells of the cyanobacterium Anabaena sp. strain PCC 7120 ΔHup, lacking an uptake hydrogenase, photobiologically produce H₂ by nitrogenase. Under N₂-rich atmosphere, the nitrogenase activity declines in a rather short time due to the sufficiency of combined nitrogen. From the parental ΔHup strain, site-directed double-crossover variants, dc-Q193S and dc-R284H, were created with amino acid substitutions presumed to be located in the vicinity of the FeMo-cofactor of nitrogenase. Unlike the case for the ΔHup strain, H₂ production activities of the variants were not decreased by the presence of high concentrations of N₂ and they continuously produced H₂ over 21 days with occasional headspace gas replacement. This property of N₂ insensitivity is a potentially useful strategy for reducing the cost of the culture gas in future practical applications of sustainable biofuel production. This Anabaena strain has only the Mo-containing nitrogenase which reduces acetylene to ethylene, but the dc-Q193S variant also produced ethane at low but measurable rates along with greater rates of ethylene production.     

Towards the improvement of thermal efficiency in lignite‐fired power generation: Concerning the utilization of Polish lignite deposits in state‐of‐the‐art IGCC technology

Integrated coal Gasification Combined Cycle (IGCC) is the most advanced technology for coal‐fired power generation. The two‐stage entrained flow gasification process allows for the use of a wide range of coal, as long as the gasification temperature is above the ash melting point of a used fuel. In this gasification technology, lignite, which often has a low ash melting point, can be preferably utilized. However, ash fluidity is also another importance, because the behaviour of molten slag can diminish a stable ash discharge from a gasifier. As the eligibility of coal ash properties is a considerable factor, water physically and chemically kept in lignite (30 – 60% in mass) attributes to deteriorating gasification efficiency, because it causes significant heat loss and increasing oxygen consumption. Developing a thermal evaporative lignite drying method will be a necessary attempt to apply lignite to the coal gasification process. For those preceded objectives, coal and ash properties and drying characteristics of several grades of Polish lignite, extracted from Belchatow and Turow deposits, have been experimentally investigated in a preliminary study evaluating the applicability and consideration for its utilization in state‐of‐the‐art clean coal technology, IGCC. This paper particularly discusses the eligibility of Polish lignite from the perspective of the fusibility and fluidity of ash melts and the fundamental drying kinetics of lignite in superheated steam in the light of water removal. The viscosity of ash melts is measured at high temperature up to 1700 °C. In the drying tests, the significant influence of structural issues, because of the provenance and origin of lignite on the drying characteristics, was found by applying the method of sensitivity analysis of physical propensity. This paper concludes that the investigated Polish lignite has characteristics favourable for utilization in IGCC technology, once the precautions related to its high moisture have been carefully addressed. Copyright © 2016 John Wiley & Sons, Ltd.     

Effect of ageing in the electrolyte and water on porous anodic films on zirconium

The present study demonstrates the significant influence of ageing in the formation electrolyte on the morphology and composition of anodic films grown on zirconium in 0.35 M ammonium fluoride in glycerol. Ageing after anodizing, by immersion in the electrolyte for 1 h, is shown to promote a transition from a porous to a nanotubular morphology, due to the dissolution of the fluoride-rich intratubular material in which the nanotubes are embedded. The morphological change is accompanied by a significant loss of zirconium and fluorine from the film. In contrast, ageing in deionized water has little influence on the films.     

Fabrication of 80 mm diameter-sized solid oxide fuel cells using a water-based NiO–YSZ slurry

Solid oxide fuel cells (SOFCs) are very attractive for their high energy conversion efficiency and low emissions. Generally, a supported layer of SOFCs is fabricated by tape casting, using an organic solvent. Recently, a slurry based on water instead of an organic solvent has been sought in order to avoid environmental pollution. In this study, the anode of SOFCs was fabricated by aqueous tape casting, and the electrolyte and the cathode were deposited by screen printing. The I–V characteristics of the cell thus obtained were evaluated. As a result, an 80 mm diameter-sized cell with a power density of 0.33 W/cm² at 800 °C was successfully fabricated by controlling sintering conditions.     

A study on physical and mechanical properties for soft to firm clays in Yangon area – Properties of clays deposit at the sedimentary basins in Myanmar

Recently, a great deal of foreign investment has been entered into construction of the social infrastructure of Myanmar. Many construction projects are therefore on-going, and these are especially planned in the Yangon area. While these construction booms are increasing, existing studies on the geotechnical problems in the Yangon area such as problematic soils like soft clays are limited at present. Information on soil properties has also not been shared and has been confined to individual projects. In this paper, the boring and laboratory tests carried out in the Yangon area are selected and focused upon among the tests carried out in Myanmar. Laboratory test results for clay deposits in the Yangon area are analyzed and the differences in soil properties between different sedimentary basins and sub-areas divided by the Tertiary sediment ridge that runs from north to south at the center of Yangon are clarified together with a comparison to the clays found in other countries, which have been previously investigated.