Reduction of nutrients in wastewater is required to deal with eutrophication in enclosed seas and lakes. Since the biochemical mechanism of nutrients removal in activated sludge processes is complicated, it is not easy to control the process appropriately depending on the fluctuations of influent wastewater. In the present study, a fuzzy control system has been developed using knowledge acquired from skilled experts and computer simulation; and applied to a two-tank intermittently aerated activated sludge process in a wastewater treatment plant which had been controlled formerly by a simple timer method. The fuzzy control system outputs the on-off of aeration using If-Then fuzzy rules depending on several kinds of input variables. In conclusion, nutrients removal and energy consumption have been improved by the application of the fuzzy control system.

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The green composite has attracted special interest recently. From the viewpoint of the effective utilization of waste wood, we proposed the composite composed of woodchips as the matrix material, bamboo fibers as the reinforced fiber and the biodegradable resin as the adhesive. The composite was formed a mixture of those materials into correct shape by press at the appropriate temperature. In this paper, in order to improve the strength of the composite, the surfaces of woodchips and bamboo fibers were modified by the alkali treatment. By examining the bending strength of the composites, it was found that the alkali treatment was effective in order to improve the bending strength of the proposed composite. Especially, it was clarified that the high bending strength was obtained in the case of combination of woodchips with the alkali treatment and bamboo fibers without the alkali treatment.

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Increasing accumulation of inorganic waste has been becoming one of the most serious problems from the point of environmental loading. As the useful mean to solve the problem the development of the recycle technique has been required. Especially the production of the new material by mixing together more than two kinds of raw materials is more useful method. However, a number of trials are required in this method. It is available to make clear the target of production first. In this study, the targets of the production are the glass ceramics with the prismatic crystals of an Anorthite,Wollastonite, and Gehelenite, and inorganic wastes as fly ash, concrete sludge, and glass cullet are selected as construction materials. Some batches were prepared by mixing these inorganic wastes in the weight ratios determined on the basis of a phase equilibrium diagram of CaO-Al2O3-SiO2 to get the desired materials. Glass samples were produced by melting the batches at 1400°C. From these batch compositions, the amorphous glasses were produced. They were reheated in the region of crystallization temperatures to make them transform into glass ceramic. The properties of the obtained glass ceramics were examined by XRD analysis, SEM observations, and strength tests by four point bending. The XRD analysis and SEM observations showed that the crystallized phase of the produced glass ceramic samples were identified as Anorthite, .Wollastonite, and Gehelenite, respectively. The strength test showed that any glass ceramics have the high strength of 80 to 90 MPa, and can be applied for various facets of the construction materials.

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The intersection at Ichiokamotomachi, Minato-ku, Osaka City was improved to take the measure against traffic congestion in June, 2008. The latest air purification technology ( ACF technology ) was applied to the construction since it was the highest-dense air pollution in Hanshin area, where is the level crossing of the National Route No. 43 and No. 172 ( Minato Street ). We had the various essential investigations at the practical application of the technology, which is verified to highly purify NO₂ and hardly cost for the maintenance as well as is conducted the different research at the Fukuoka Institute of Health & Environmental Sciences, the Environmental Restoration and Conservation Agency, and Kyushu University. We report the development of AF and its structure, the result of the purification experiment indoor and in the field of Route No.43, the adjustment to the local pollution areas and the effect to reduce of the air pollution.

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Nowadays, ”Green IT” has become the important keyword for the sake of the construction of the society where the environmental protection and the economic growth dwell together. Regarding IT, content services is one of the most important services in the Internet and most of Internet Service Providers (ISPs) challenges to provide better content services. To provide content services efficiently, Content Distribution Networks (CDNs) have to be optimally constructed. In this paper, we introduce the examples of several major ISPs in Japan as the case studies of CDNs operation and execute simulation experiments of dynamic content allocation in CDNs of BBit-Japan using the optimal mirror server and content file allocation model.

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Horizontal gas injection is commonly used in the refining processes such as the desulphurization process and AOD process. This paper deals experimentally with wave motions in a water-filled cylindrical bath into which air is injected through a L-shaped lance placed at the bath centerline. Experiments are made on the patterns of wave motions on the bath surface. The wave motions of a bubbling jet are observed by eye inspection and with a digital video camera from the side and top of the vessel. It is found that a swirl motion appears as one of the wave motions under a certain condition. In this study, we further focus on the occurrence condition of a deep-water wave type swirl motion, swirl period and amplitude. The measured values are compared with empirical and theoretical equations proposed previously for the bottom blown bath.

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The width of cross flow fan impeller can readily be changed depending on its usage. The effect of the width on the cross flow fan characteristics however is not fully understood yet. In this study three types of extremely short impellers are produced and their performance and noise level are experimentally investigated. In addition, three kinds of casings with different shape are used for the measurements. High fan performance and low noise level can be achieved for a given impeller by choosing adequate casing shape.

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Dr. Teruo Yamamoto proposed a unique method of noise reduction of a cross flow fan in his patent. He suggested that fan noise could be reduced by using annular band (annular groove) set around the impeller of arbitrary section. We ascertained previously the annular band effect only when it was set around the two ends of impeller. However, the annular band effect is not obvious when it is set at the different position of the impeller. His method is very interesting and seems to have bigger possibility of noise reduction. In this study, the annular band effect is examined by changing the setting position of the band along the impeller.

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The purpose of this paper is to investigate a mechanism on drag reduction of a rectangular cylinder with small cut-corners at the front-edge. The rectangular shape is selected in three kinds of the length-to-breadth ratios: 2/6, 4/6 and 6/6. The visualization techniques include the hydrogen-bubble technique for Re=4,000 and the X-type hot wire anemometer in a wind tunnel for Re=50,000. A similar reattachment flow pattern is observed, although the length-to-breadth ratio is less than unity, in two values of the Reynolds number between 4,000 and 50,000. This implies that the drag reduction would occur even for a separated laminar shear layer if one selects an appropriate shape of the cut-corner unlike the previous findings.

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In order to evaluate the plastic deformation of mechanical members, we pay attention to surface temperature that is generated by plastic deformation. Most of the plastic energy exhausted by plastic deforming is converted into heat. The distributions of the generation represent the macroscopic plastic deformed intensity. In the present study, the tensile tests were performed on stainless steel (SUS304) plate with a center crack. We measured the distributions of surface temperature by using the thermocouples and thermography (TVS: Thermal Video System) under the plastic deformation and crack propagation. Furthermore FEM elasto-plastic analysis couples with transient heat conduction analysis was performed. The analysis results were good agreement with the experimental ones and the propriety of this non-contact measurement system of plastic deformation and fracture process by thermography system was shown.

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