A physical model for engine control design via role state variables

The present paper describes a model representation of the multi-cyclic phenomena of a multi-cylinder engine system. The model is simplified for the implementation of a practical engine controller. The simplified model is described by physically meaningful state variables, which enables controller designers to effectively consider practical objectives and constraints. The proposed approach consists of two steps. First, an approximate analytical discrete-crank angle model, which is a periodic state equation, is derived from the gas equations, the conservation laws, and the motion dynamics. Second, the concept of role state variables is proposed to transform the periodic state equation into a time-invariant state equation. The stabilizability and detectability of the time-invariant state equation are shown to be equivalent to those of the periodic state equation. The time-invariant state equation is used to design cold start feedforward and feedback controllers.     

Microstructure and dielectric properties of sintered Li–Nb–Ti–O solid solution ceramics having superstructure

Effects of preparation conditions on the microstructures and periodicity of the superstructure for Li_1+xNb_1–xTi_xO₃ phase M polycrystals were investigated. Obtained specimens, mainly comprised of elongated plate-like grains, and their surfaces were found to be parallel to periodical domains. Sintered materials were found to contain Nb-doped Li₂TiO₃ based solid solution that was one of the end members in the phase diagram of constituent materials. Superperiodicity of phase M was found to be affected by the both chemical compositions and sintering conditions. The dielectric constant increased with increasing of periodicity of superstructures, which could be varied by the amount of Ti concentration. Electronic Publication     

Changes in year-round air temperature and annual energy consumption in office building areas by urban heat-island countermeasures and energy-saving measures

This paper describes the effects of the installation of various countermeasures against urban heat-island (UHI) and energy-saving measures on UHI and global warming. A UHI and energy-consumption simulation model was developed by combining the one-dimensional meteorological canopy and building energy use models; further, the proposed model was expanded to evaluate the year-round air temperature and annual energy consumption. The simulation results showed that the humidification and albedo increase at building-wall surfaces reduced the total number of hours for which the air temperature was more than 30 °C during the daytime by more than 60 (h) per year. The UHI countermeasures reduced the annual energy-consumption despite causing a small increase during the winter period. However, they may result in certain unfavorable conditions for pedestrians. Energy-saving measures, on the other hand, reduce the total number of hours for which the air temperature is more than 30 °C by only a few hours per year. Thus, we demonstrate the effectiveness of the UHI countermeasures and measures against global warming by extending the calculation period from summer to an entire year.     

Liquid-Phase Oxidation of Benzene to Phenol by Molecular Oxygen over La Catalysts Supported on HZSM-5

The liquid-phase oxidation of benzene to phenol over lanthanum oxide catalysts (LaOx/HZSM-5) supported on HZSM-5 was studied in the presences of oxygen as an oxidant and ascorbic acid as a reducing regent. LaO_x/HZSM-5 effectively catalyzes the formation of phenol at 353 K under the pressurization of oxygen. The LaO_x/HZSM-5 catalysts take place no leaching of lanthanum species from the catalysts to acidic solvent. Therefore, it is demonstrated that the supported lanthanum catalysts are stable and reusable for the benzene oxidation even in the acidic reaction solution.     

Renewable resource based biocomposites from natural fiber and polyhydroxybutyrate-co-valerate (PHBV) bioplastic

Renewable resource based green biocomposites were prepared using a bacterial polyester i.e., poly(hydroxybutyrate-co-valerate) (PHBV) and natural bamboo fiber. Fabrication of the biocomposites was carried out by injection molding following extrusion compounding of PHBV and bamboo fiber with 30 or 40 wt.% fiber. The mechanical, thermo-mechanical and morphological properties of the biocomposites were evaluated. Little variation in the thermo-mechanical and impact properties was observed when the fiber content was varied. The tensile modulus of biocomposites at 40 wt.% fiber improved by 175% as compared to that of neat PHBV. The theoretical tensile modulus of the biocomposites was calculated using Christensen’s equations and compared with the experimental results. It was found to be in near approximation to the experimental data. The storage modulus was affected slightly by the variation of fiber content from 30 to 40 wt.% in biocomposites. The heat deflection temperature of PHBV increased by 9 °C at 40 wt.% of fiber reinforcement. Morphological aspects and thermal stability were studied using scanning electron microscopy and thermo-gravimetric analysis, respectively. In addition, a comparative analysis of bamboo fiber–PHBV with wood fiber–PHBV biocomposites was performed. Statistical analysis of both biocomposites was carried out by performing a two-way ANOVA on their tensile and flexural moduli in order to evaluate the effect of fiber type and content in the PHBV matrix.     

The effect of the molecular structure of a cationic azo dye on the photoinduced intercalation of phenol in a montmorillonite

The effect of the molecular structure of a cationic azo dye on the photoinduced intercalation of phenol into the azo dye-montmorillonites was reported. Two types of cationic azo dyes were used; one has (2-hydroxyethyl)dimethylammonium group (AZ(OH)⁺), and the other has trimethylammonium group (AZ(CH₃)⁺). Phenol was intercalated into both cation exchanged azo dye-montmorillonites (Kunipia F) by mechanical mixing without solvent. By the UV irradiation, the basal spacings increased further, and subsequent visible light irradiation led to decrease the basal spacings, indicating the intercalation and the deintercalation of phenol by the UV and visible light, respectively. The amounts of the phenol intercalated both chemically and photochemically varied depending on the azobenzene cations, showing the interactions between the cationic head group and phenol.     

A REACTION-EXTRACTION-REGENERATION SYSTEM FOR HIGHLY SELECTIVE OXIDATION OF BENZENE TO PHENOL

The reaction-extraction-regeneration system for the liquid-phase oxidation of benzene to phenol in the benzene-water-oxygen system was investigated. Phenol was extracted in the extractor to reduce the concentration of phenol in the benzene phase. As vanadium catalyst was oxidized to inactive species after the oxidation reaction, the regenerator was installed in the system to reduce the oxidation state of vanadium catalyst from V⁴⁺ or VO²⁺ to the active V³⁺ under H₂ flow. The effects of various operating parameters including concentration of VCl₃ catalyst, O₂ and H₂ flow rates, benzene bubble size, pH, surface area of Pt regeneration catalyst, the metal species, and amount of ascorbic acid were investigated. Ascorbic acid was employed as a reducing agent for helping reduce the V⁴⁺ form to the active form and therefore improving the activity of vanadium catalyst. VCl₃ catalyst concentration of 10 mol/m³ with pH of 3–4 in the reactor and Pt surface area of 0.05 m² in the regenerator showed optimal conditions for the system.     

Comparison of Performances of Turbines for Wave Energy Conversion

The Wells turbine for a wave power generator is a self-rectifying air turbine that is available for an energy conversion in an oscillating water-air column without any rectifying valve. The objective of this paper is to compare the performances of the Wells turbines in which the profile of blade are NACA0020, NACA0015, CA9 and HSIM15-262123-1576 in the small-scale model testing. The running characteristics in the steady flow, the start and running characteristics in the sinusoidal flow and the hysteretic characteristics in the sinusoidal flow were investigated for four kinds of turbine. As a conclusion, the turbine in which the profile of blade is NACA0020 has the best performances among 4 turbines for the running and starting characteristics in the small-scale model testing.     

A novel immunostimulating aspect of Lactobacillus gasseri: induction of "Gasserokine" as chemoattractants for macrophages

The chemotactic activity of the culture supernatants from 14 strains of Lactobacillus acidophilus and L. gasseri was examined for murine macrophages. Significant macrophage chemotactic activity was observed in three strains of L. acidophilus and all strains of L. gasseri. The highest activity was observed in the supernatant (1131-sup) from 24-h cultures of L. gasseri JCM1131T. The chemotactic factor from 1131-sup, designated as "Gasserokine", was purified by the C18 reverse phase and ion-exchange chromatography. The purity of Gasserokine was checked by HPLC with the reverse-phase mode. The chemotactic activity of Gasserokine was also observed for human monocytes. The macrophage chemotaxis induced by L. gasseri JCM1131T culture supernatants was discovered to be a new biological function exerted by probiotic lactic acid bacteria. Therefore, the activity is expected to be used for one of the functional parameters in the immunomodulating properties of probiotic lactic acid bacteria.