This study was aimed at estimating effective shear stress working on flat sheet membrane by the addition of fluidized media in MBRs. In both of laboratory-scale aeration tanks with and without fluidized media, shear stress variations on membrane surface and water phase velocity variations were measured and MBR operation was conducted. For the evaluation of the effective shear stress working on membrane surface to mitigate membrane surface, simulation of trans-membrane pressure increase was conducted. It was shown that the time-averaged absolute value of shear stress was smaller in the reactor with fluidized media than without fluidized media. However, due to strong turbulence in the reactor with fluidized media caused by interaction between water-phase and media and also due to the direct interaction between membrane surface and fluidized media, standard deviation of shear stress on membrane surface was larger in the reactor with fluidized media than without media. Histograms of shear stress variation data were fitted well to normal distribution curves and mean plus three times of standard deviation was defined to be a maximum shear stress value. By applying the defined maximum shear stress to a membrane fouling model, trans-membrane pressure curve in the MBR experiment was simulated well by the fouling model indicting that the maximum shear stress, not time-averaged shear stress, can be regarded as an effective shear stress to prevent membrane fouling in submerged flat-sheet MBRs.

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 Preferences or perceptions of ordinary citizens on three kinds of nonconventional water resources including rainwater, permissible groundwater exuding to underground railway stations and tunnels and reclaimed wastewater were investigated by use of the Internet survey method. The survey results were analysed with analytical hierar chal process (AHP) and willingness to pay (WTP). Weight vectors of natural environment and people's lives were found larger than other three first order evaluation conditions, society, economics and technology. The order of the weight vector values for the three water resources were rainwater, reclaimed wastewater and permissible groundwater. That for the five water usages were agricultural and horticulture water, water storage in preparation for disaster, toilet flushing water, environment water and sprinkler water for washing road and cooling atmosphere temperature. The difference between toilet flushing water and environment water was not significant by 5% significance. The analyzed data showed that differences between the weight vector values of the alternatives (water resources and their usages) became small by increasing the number of the evaluation conditions, which would be a topic to be resolved for AHP application to actual public projects. For water resources, WTP with public budgets was Japanese Yen (JY) 53,100-55,100 person^-1 year^-1, and WTP with private finances was JY 19,100-20,800 person^-1 year^-1. For water usages, public WTP was JY 20,400-47,200 person^-1 year^-1 and private WTP was JY 8,400-16,000 person^-1 year^-1. The orders of WTP values were similar to the orders of the weight vector values for both water resources and their usages obtained by the AHP analysis. Effective dissemination subjects and objects of the nonconventional water resources and their usages were extracted by the analysis for attributes including sex, age, living area, occupation and education.

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 We analyze effluent water quality and electricity consumption after in troducing advanced treatment in sewage treatment plant. We define 'advanced treatment ratio' as volume of treated water through advanced treatment processes divided by total volume of treated water in plant. Advanced treatment ratio represents degree of introducing advanced treatment. We build two types of equation. One represents relation between effluent water quality and advanced treatment ratio, the other between electricity consumption and advanced treatment ratio. Each equation is fitted by least squares on 808 samples: 8 fiscal years operation data of 101 plants working in Kanagawa, Tokyo, Saitama and Chiba areas, and coefficient of advanced treatment ratio is estimated.
 The result is as follows.
(1) After introducing advanced treatment aimed at nitrogen removal, T-N in effluent water decreases by 51.3% and electricity consum ption increases by 52.2%.
(2) After introducing advanced treatment aimed at phosphorus removal, T-P in effluent water decreases by 27.8%.
 Using the above result, we try prioritizing 71 plants in Tokyo Bay watershed about raising advanced treatment ratio, so that, in total, pollutant in effluent water decreases with minimized increase of electricity consumption.

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 Methane hydrate (MH) is expected as a new resource of natural gases. However MH is solid and it doesn't flow, thus dissociation methods of MH into water and CH₄ gas in oceanic sedimentary layers are necessary by depressurization. Offshore production test is planed in 2012 and 2014 by Japan national project by using the depressurization.
 On the other hand, enhanced oil recovery using CO₂ has been commercialized since 1970's in the US. CO₂ should be used for recovery of methane hydrate to achieve both high productivity and mitigating CO₂ release to the atmosphere in the same manner. We had proposed an enhanced methane hydrate recovery method using exothermic heat of CO₂ hydrate formation to raise the temperature of sedimentary layers. However, it is said that CO₂ can't inject into layers, because CO₂ hydrate blocks the pore of sediments. So we have validated the CO₂ injection principle considering the temperature of sedimentary layers by laboratry experiments. These results show a possibility of long-term CO₂ injection into layers.

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 Some countermeasure methods against the environmental ground vibration caused by some traffic vibrations have been proposed so far. The authors have developed a new type ground vibration isolation wall using scrap tire, and evaluated its effectiveness on the ground vibration reduction by full scale field tests.
 In this paper, the authors discussed and examined the effectiveness of the developed countermeasure method by two field tests. The one concerns on the effect of scrap tire as soft material of vibration isolation wall, and the other on the effect of the developed countermeasure method practically applied in a residential area close to monorail traffic. As the results, it was elucidated that the ground vibration of 2-3 dB was reduced in case of two times volume of the soft material, the conversion ratio of the vibration energy of the soft material to the kinetic energy was higher than that of the core material of PHC pile, the vibration acceleration of 0.19 - 1.26 gal was reduced by the developed countermeasure method in case of the monorail traffic, and the vibration reduction measured behind the isolation wall agreed well with the proposed theoretical value, together with confirming the effectiveness of the ground vibration isolation wall using scrap tire as the countermeasure method against the environmental ground vibration.

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 The object of this study is to find measures for reducing the noise generated when heavy vehicles run across the expansion joints of a steel viaduct in one urban area. For this study, both the vibration acceleration of the viaduct and the radiated noise are measured. Some strong relations between radiated noise and the vibration of the viaduct of girder members at some frequencies are identified. Taking into account the characteristics of the vibration and radiated noise, and the conditions of the viaduct site, the use of magnetic constrained-layer dampers are proposed for controlling the radiated noise. Some vibration tests and acoustic tests were performed on six kinds of magnetic constrained-layer dampers in order to find out the most effective way to reduce radiated noise.
 This paper describes the characteristics of the vibration at main gider members and those of the radiated noise. Magnetic constrained-layer dampers are proposed for reducing the radiated noise. It also takes into account the raffic noise around the viaduct.

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 This paper describes how to develop and evaluate a new biocatalyst method for biodiesel fuel based on the lipase production fungus. This method can convert waste vegetable oil into biodiesel fuel without alkaline waste fluid and byproducts (gly cerine). The main outcomes of this research were: (1) The biodiesel fuel can be manufactured from lipase production fungus (Rhizupus oryzae NBRC 9364). (2) The lipase activity can be enhanced by adding glucose and oil. (3) Phased addition of the methanol enhances the conversion rate of the biodiesel fuel (Maximum conversion rate is 85%). (4) The proposed method can improve vehicle exhaust emission and reduce byproducts (glycerine). We concluded that our proposed methods are effective for the production of biodiesel fuel from waste vegetable oil.

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 In recent years, the Ariake Sea environment has become severely degraded, resulting in changes in biota, a marked overall decrease in the number of species, frequent outbreaks of red tides, and the deterioration of water quality and the sediment environment. In this study, we examined the relationship between increases in red tide frequency and duration and fluctuations in the aquatic environment. We also investigated the distribution of sediments, and the correlation between benthic species distribution and sediment type. The results show that interannual fluctuations in water quality (water temperature, transparency, and nutrient levels) were responsible for the increases in red tide outbreaks. The Ariake Sea was divided into zones on the basis of the granularity and chemical characteristics of the sediment. The results showed differing number of benthic species in each zone, demonstrating a relationship between the sediment environment and benthos distributions.

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