We are studying a new analysis method for transient responses by using the digital filter. This paper demonstrates some time-frequency analysis results of responses based on typical differential equations. First, we present the results for the linear free and forced vibration responses of one degree-of-freedom system. Then we consider the responses based on Duffing's equation and it is shown that the dominant frequency change of the responses can be visualized in the time-frequency analysis results. And the responses based on Van del Pol equation are analyzed to understand the several dominant frequencies. Finally, we apply the time-frequency analysis to the data of car bumping and it is shown that the phenomena may be described by the Duffing's equation.

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We have developed a noise control system, which arrayed the noise insulation panels with piezoelectric material in plane, to reduce the transmitted noise through any plate or emission noise from the noise source. This paper describe about a noise control effect that the noise control system installed to a hydraulic machine. The emission noise from the hydraulic machine reduced about 15dB at 150Hz with control using induction analog control circuit.

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In recent years, with the never ending progress in technology related to audio visual equipments and PC, etc., there is an increasing trends of using the reproduction sound of contents such as music and speech even for household purposes. Since all the phenomena occurring in nature need to be considered in relative frame of reference, a pleasant and enjoyable sound to the listener may appear as a noise to the people (non-listener) around the owner of sound player. Therefore, the aim of the present work is to develop a sound field control technology which confined the sound field to the listener only. Then, the authors propose a method to change attenuation ratio so that sound pressure level remain same in the near field, but its level reduces in the far field. By setting up the acoustic impedance barrier with multiple error sensors on the side, the sound attenuation level on the side is improved. Based on the experiment and theoretical estimation the performance of the present technique is verified.

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The engine sound becomes predominant in accelerating cars. Recently, the examination such as throwing the engine intake noise into the driver's seat as the attempt of the sound design intentionally has been performed. However, the auditory impression of engine acceleration might deteriorates by half degree element and the disorder of harmonic structure. Then, we developed real signal Command LMS algorithm, corrected the disorder of harmonic structure using active sound control and obtained an effective result.

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In an ordinary active noise control (ANC), an error microphone is settled in the control area but it can be an obstacle of human movement. We proposed Virtual Microphone System (VMS) that an error signal can be obtained from the error microphone settled out of the control area. We applied VMS to Active Sound Shielding and succeeded in the reduction of the noise. The effect of the reduction is approximately 16.4dB. We measured the sound pressure distribution in the control area and analyzed the acquired data in the octave band of 125Hz to 2kHz. From the measurement, an enough control effect was obtained in frequency bands of 250, 500, 1k and 2kHz.

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The present paper describes the experimental investigation of characteristics of adaptive feedforward active control systems of beat noise in ducts. Dual-input, dual-controller and single-output(2-2-1) system has been proposed to improve the performance of the active control. Proposed 2-2-1 system can achieve relatively large attenuation and can converge rapidly in comparison with the conventional single-input, single-controller and single-output system. Results show that the step-size of the 2-2-1 system increases as the frequency separation increases and noise reduction increases as the step-size increases. Results show that the fastest convergence is obtained by the optimum step-size for a given frequency separation and sampling frequency.

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On active noise control in 3-dimensional acoustic field, a control effect becomes worse when an evaluation point moves. Against this problem, we proposed a control algorithm using filter map. Validity of this algorithm was shown by simulations and experiments. To use the method, however, the adaptive filters must be accumulated in a controller so that the required memory becomes large. Moreover, highly computational power is necessary. Therefore, reduction of both required memory and computational power is necessary. In this paper, a method for the reduction is proposed. In the method, IIR filter and Steiglitz-McBride algorithm are used. The validity of proposed method is shown by experiments.

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Double-leaf sound insulating wall is widely applied to cabins of air-plane or high-speed train, because transmission loss is larger nevertheless the weight is light. But transmission loss of double-leaf is decreased at the resonant frequency of the wall. So we tested tuned mass dampers and tuned mass dampers with damping to increase transmission loss at the resonant frequency. And we observed vibration modes of the surface of the wall and measured the transmission loss. Those results show that vibration modes which are generated by tuned mass damper and tuned mass damper with damping affect the sound transmission loss.

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In the present paper the attention is focused on the effect of small cavities inside in-line tube banks on vortex shedding. We measured the SPL of acoustic resonance, the spectrum of velocity fluctuation, the amplitude and phase delay of acoustic pressures and the gap velocity. As a result, we found broad-band frequencies of velocity fluctuation with Strouhal number about S_t=0.09-0.22 in the cavities without acoustic resonance. The center frequency of velocity fluctuation was about S_t=0.15. The vortex shedding frequency in the cavities was the same as the result of no cavities. And the periodicity and intensity of velocity fluctuation due to vortex shedding increased rather than that of tube banks. Therefore, it was easy to generate acoustic resonance of S_t=0.15 when there were small cavities inside in-line tube banks.

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The purpose of this research is to clarify the generation mechanism of aeroacoustics feeddback noise radiated from a flat-plate cascade. The experimental results showed that the resonance frequency of the tonal noise can be determined with the chord length of the flat plate. The open-end correction depends on not only the distance between the blades but also chord length. The empirical equation of the open-end correction was suggested by using the experimental data. The second peak strongly depends on the offset length of the leading edge of the flat plates. The vortex structures were visualized by using the high-speed camera. In the case of resonance mode, the phase differences between the vortices shed from the flat plates were almost constant. The coherence between the vortices and the resonance noise was higher than that of non resonance vortices.

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A sound level of noises generating from aero flow often grow by resonance of eddy fluctuation sound around structure objects and by lock-in phenomenon of the eddy fluctuation into the resonance sound frequency. An understanding of lock-in conditions is important to the control of the aero flow noise. We made a virtual resonance system in an edge-tone system by adding of disturbance sound to a part of the air nozzle and measured frequencies and sound pressure levels of the disturbance sound. This study evaluates the condition of lock-in phenomenon from the results. Edge tone locked in disturbance sound at about -18dB from the edge tone level without disturbance if the edge-tone frequency is close to disturbance frequency. If the edge-tone frequency is 20% away from disturbance, edge-tone locked in at a few dB lower than edge tone level.

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This paper describes methods for construction of energy models of structural systems based on experimental data and prediction accuracy for modeling to correspond to the system with low modal densities. First, the method for construction of model as to Statistical Energy Analysis (SEA) and Energy Distribution (ED) are summarized. Then the comparison between SEA and ED are performed to the system comprising three series plates. As a result, the calculation of the correlation factor of normalized subsystem energy and loss factor clarified the condition shows the negative value of loss factors.

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This paper is one report of a series of trying to develop a new method for reducing structure-borne sound by using structural intensity technique. We are studying the use of the modal form of structural intensity on plate to control the intensity distribution by changing the excitation conditions or/and designing structure. In this paper, it is shown that the modal form of the intensity on plate can be also effective to analyze the intensity on plate compound structure composed of three flat plates. It is also confirmed that the vortex cross-modal functions on the structure have no contribution to transmitted power on a plate and between plates. Next, we report one example as the structural design considering structural intensity. In the example, we make vortex type structural intensity by setting one reinforcement beam on plate under the excitation condition without vortex type intensity distribution on the plate.

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Active noise control using the feed-forward method requires an enough long distance (d) between the reference microphone and the control speaker, to satisfy the causality law. In this research, it was proved that the high sampling frequency and the high computation speed could make the distance d very short. A compact active acoustic cell whose d is 10mm was developed by using a flat speaker and a FPGA controller with 100kHz sampling frequency. Even in the case with an ordinary dynamic speaker whose diaphragm is 70mm diameter, the above high speed signal processing system could reduce the distance d down to 60mm. This is effective for realizing the active acoustic shielding system.

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Passive noise control such as sound absorption and sound insulation is commonly used as noise reduction measures. It is effective against high-frequency noise, but not effective against low-frequency noise. As appropriate measures for the low-frequency noise, there is active noise control (ANC) system. The system generates a sound whose amplitude is same as noise and phase is opposite to noise. The sound causes the acoustic wave interference and erases the noise. It is used well in one dimension space like the duct, but there are few examples of practical use in three dimension space. Then, we developed the ANC system that can be applied to three dimension space.

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The low frequency noise is not clearly defined but is generally taken to mean noise below a frequency of about 100 to 150 Hz. Noise at frequencies below about 20 Hz is sometimes referred to as infrasound and this type of noise presents even greater difficulties in its measurement and assessment. The objective of our study is to suggest practical means of reducing the low frequency noise emanating from the opening of soundproof houses. This paper describes an experimental study on the alleviation of low frequency noise by the active noise control (ANC) in a house.

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It is increasingly needed to reduce the noise in the interior of train cabin because it is increasingly demanded to have a comfortable riding for high speed trains while noise becomes greater as trains run faster. As for this problem, recently the noise reduction system with piezoelectric material has been noted because it makes it possible to reduce vibration and noise at high efficiency without adding mass apparently by dispersing the energy of vibration actively. To improve the performance of this system, it is necessary to optimize the control method of piezoelectric material with electrical circuit. This paper describes the result of the optimization of control method of the system with piezoelectric material to reduce the noise.

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Fans are dominant noise source of computer equipments. Their noise can be reduced effectively by louvers with absorbing materials. In order to optimize their noise reduction performance, insertion loss of a louver is simulated by boundary element method (BEM). In this simulation, incoherent vibrating surfaces are used to simulate fan noise sources. Acoustic impedance of a multi-layered absorptive material is calculated using transfer matrix method. Results show that the simulated overall noise agrees with the measurement within 1 dB.

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Impact noise due to trains passing over rail joints causes a serious problem at the wayside of railway. Therefore, an effective countermeasure against the noise generated by rail joint is required. New equipment for rail joint named "Noise Insulator for Rail Joint" has been developed. The insulator consists of bonded small inorganic particles in which glass wool and polyvinyl chloride sheet mixed with the steel powders are packed. The insulator is installed at the nearby rail joint and absorbs and insulates a part of noise radiated from rail joint. Endurance test on the material of bonded inorganic particles of the insulator and noise measurement of train pass-by at commercial line were carried out to evaluate the practicality of the equipment. Consequently, the insulator showed efficient durability, and noise reduction of 1〜2dB in noise level was achieved at the trackside.

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Some ceiling-mounted ventilators have the function of sound attenuation by a resonant effect in a chamber consisting of a rectangular outer cover and a cylindrical fan unit. The properties of the chamber have been studied using several simple models of the chamber by measurements and numerical calculations. The chamber consisting of two specific regions basically behaves as a Helmholtz resonator of two degrees of freedom. In this research, the second region of the chamber is filled with an absorbing material (a fibrous material). The effect of it on the sound attenuation properties of the chamber is studied experimentally using an axisymmetric chamber located at the end of a hemi-infinite duct. The frequency response of the chamber changes from that of two degrees of freedom to that of single degree of freedom as the density of material increases. While the sound attenuation level falls around the resonant frequencies, it rises in the intermediate frequency range. The properties are also examined by numerical calculations using a FEM software that gives reasonable results to describe the measured results. In the present model, the flow resistivity of the material is the decisive valuable among the several valuables defining a porous material. As the effect of the absorbing material, the resonant character diminishes in the sound field of the chamber.

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In recent years, the silence of hybrid cars is regarded as questionable from a viewpoint of pedestrian protection. This situation tends to obligate to add the car sound. In this study, we focused on half order spectrum and then subjective preference (subjective annoyance) of acceleration car sound for subjects who infrequently drive a car and who frequently drive it was evaluated. In addition, a sinusoidal model was adopt for acceleration car sound synthesis and the auditory impressions of car acceleration sound was examined using the psychological method and brain magnetic fields.

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A method for measuring an oblique incidence absorption coefficient is proposed in this paper. Time streched method is generally used to measure it. But this method needs large specimen and wide area to separate direct acoustic wave and reflex wave. We tried to study the applicability of short acoustic tube to measure it through experiment, one dimensional theoretical analysis and three-dimensional numerical analysis. We found that proposed method is applicable under the incident angle 45 degree, if the surface of the material is locally reactive.

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The tube banks are set up in the duct of heat exchanger such as boilers etc. When the frequency of Karman vortex behind the tube banks is close to the natural frequency of duct, the self sustained tone is generated. Generally, the method of inserting the baffle plate in tube banks is adopted as self sustained tone measures. However, when there is a space between tube banks, the method of inserting the baffle plate is indefinite. Then, to examine the generation mechanism and the countermeasure of the self sustained tone for tube banks with cavity, the experiment and the analysis were carried out in this study.

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Last time, we reported the applicability of the simulation using the fluid sound analysis based on comparison of the simulation result with the measured result of the noise of actual traction motor. (hereafter referred to as device) And we reported that the simulation result has approached the measured result of the noise of the device by optimizing the noise source condition. Now we can design an optimum device without manufacturing, based on estimation of the noise generation status inside the device by the simulation using the fluid sound analysis. This time, because of changing cooling fan's shape and simulated it newly based on this method, we report the results of them.

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The ring fan is a propeller fan by an axial-flow impeller that has a ring shape shroud on the blade tip side. In this study, the whole flow field of the ring fan is simulated by a CFD code; the aerodynamic noise generated by the fan is predicted based on the wake characteristics. Moreover, the accuracy of the CFD code has been verified by comparing with the aerodynamic characteristics of the propeller fan of a current model. The aerodynamic characteristic of the ring fan by the CFD can represent the tendency of the measurement value qualitatively, however, the flow rate in the CFD becomes 30% lower than the actual measurement value. The main flow domain of the ring fan is formed at the tip side of the blade since the blade tip vortex is not formed at the blade tip side. Therefore, the relative velocity of the ring fan becomes fast by the circumferential velocity. The sound pressure levels of the ring fan in the frequency band less than 200 Hz become larger than the propeller fan. According to the analysis on the wake characteristics, it clarified that (1) Karman vortex at the main flow domain is shedding in the frequency domain lower than 200 Hz, (2) the aerodynamic sound of the ring fan in the vortex shedding frequency becomes large because of an increase in the relative velocity and the velocity fluctuation.

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The three dimensional structure of the wake vortex was investigated in relating to the aeolian tone from the swept flat plate, which is installed in the uniform flow from zero to thirty degree of the swept angles with upper and lower wall. It was pointed out that the aeolian tone is largest not at zero, but at ten degree of the swept angle. It is proposed to estimate the correlation length that is corresponding to the sound source. The length is decided from the inclination of the vortex and the secondary wake vortex. They are relating to the span-wise velocity and the ratio of the vorticity components in the dead air region.

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The author reports on a view of environmental chemistry that development of the new automatic carbonization device for waste treatment. The environmental load of our plant is remarkably small. It is able to process waste of component more than 95% of water and/or waste of high in quantity without a preprocessing process out of this apparatus. It is carbonized in this system for every waste except metals and glass. In addition, the author reports a part of the application for the charcoal derived from this equipment, such as a roof replanting for the heat island countermeasure.

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Sapporo Plastics Recycling Corp., Ltd. (SPR) which had started commercial operation of waste plastics liquefaction plant in 2000 when "The Containers and Packaging Recycling Law" had been enforced fully, has entered 10th year of operation. Only hydrocarbon oil has been recognized as recycled product derived from the waste plastics liquefaction plant of SPR by law. As a result, SPR has achieved high recycling rate, in addition, more than 90% of the recycled products have been reused in Hokkaido. Overcoming the operational obstacle caused by corrosion and clogging, SPR has been working towards maximizing recycling rate. In 2009, SPR accomplished full operation to recycle 14,000t municipal waste plastics without big troubles. Moreover, cascade recycle which chemical recycle (CR) will be done for selected waste plastics mixed with material recycle (MR) residues after material recycle was studied in 2008.

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Rice husk-based activated carbon (RHAC) in which silica was removed at different levels by means of the immersion in NaOH solution was fabricated for the adsorptive removal of dibenzothiophenes (DBTs) in commercial kerosene. The removal performance of RHACs was evaluated in batch and fixed-bed flowing desulfurization tests. RHAC with lower silica content showed greater textural property, maintaining the DBTs concentration in the effluent kerosene lower for longer time in the fixed-bed flowing test.

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The composites were fabricated from agricultural waste of rice husk (RH) and industrial waste of carbon fiber (CF) ends. The powder-state RH mixed with chopped CF ends (0 to 40 mass%) was molded into a disk by means of hot pressing in an inert condition without using any binders, and then heated at high temperatures by using an electric furnace. The surface static and kinetic friction coefficients of the composites were evaluated under the contact with a SUS304 ball. The composite added with 20 mass% of chopped CF and heated to 1000℃ displayed the lowest static and kinetic friction coefficients, which were respectively 0.14 and 0.12. It was found that frictional properties of the composite were affected by thermal shrinkage of the matrix material derived from RH, the level of the added chopped CF, and crystallization of silica provided from RH.

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For the purpose of developing a low cost bio-oil production process, we have investigated rapid pyrolysis of woody biomass by using an entrained flow reactor as the key device. The entrained flow reactor was selected because of the fine controllability of reaction temperature and residence time, which were the main factors affecting liquid products yield. In the bench-scale testing facility with entrained flow reactor, wood particles were rapidly pyrolized and the products were collected to analyze. The yield of bio-oil was higher than 50wt% compared with the fed biomass in dry weight. The obtained bio-oil formed two layers, which were hydrophilic layer containing condensed water and hydrophobic layer settled on the bottom. The moisture of hydrophilic layer should be removed and the products are expected to use as an alternative to heavy fuel oil.

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Combustion tests were conducted in an actual incineration plant in order to evaluate the bio-oil as alternative kerosene. Large differences in combustion characteristics, such as exhaust gas compositions and temperature conditions, were not observed in these tests, so that the bio-oil is considered to be used as a kerosene alternative.

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The recovery of carbon dioxide (CO_2) is one of the most important topics to improve global environments. The exhausted gases from power generator using petroleum and coal or incinerator include more than 10% of CO_2 which is excellent source for the multiplication of plants in which photosynthesis occurs with CO_2 and water. The higher the concentration of CO_2 is, the more the reaction rate gains. We have studied and found the species of green algae useful for recovery of CO_2 and the proper condition to best growth of the algae under the high concentration of CO_2 in a continuous flow water bath. However, the contact of solid (green algae) and gas (CO_2) is difficult to manage in the industrial scale. The whole system, the target and the technology will be presented.

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Black liquor produced during the pulping process is the main source of serious environmental pollution that pulp industry made. The three dominant components of black liquor are chemicals, lignin and hemicelluloses. In traditional processing method, black liquor is usually burnt to manufacture electricity supporting normal production and recovery alkali to reuse as pulping chemical. However, combustion efficiency of alkali recovery furnace was not high, resulting incomplete combustion of organic material and air pollution. For example, deleterious gas created during combustion bring secondary pollution. New cost-effective ways dealt with the black liquor are called to be found for the requirements of protecting environment and making profit. In this paper, the various situations for high-valued utilization of lignin from black liquor are reviewed, including the process of lignin oxidation into aromatic components and new gasification of black liquor to manufact DME.

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The recycling process was examined by using the industrial waste, such as clays, sands and slugs. Newly developed porous charcoal-like ceramics were expected to use for the wide application due to its unique features. The manufacturing process of the material with arbitrary shape was established and various properties were evaluated. Styrofoam mixed in the clay was lost during sintering then making the cavity in the ceramics. Consequently unburned carbon coated the ceramics surface by heating in non-oxidation atmosphere then making the material charcoal-like black. Volume fraction of styrofoam is the important factor influencing on water absorption, insulation and compressive strength. This material possessed the superior absorption of hazardous chemical substance, such as ammonia and formaldehyde.

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In recent years, the urban heat island to which the temperature of urban areas becomes high the shape of an island compared with the suburbs is regarded as questionable. As for this urban heat island, increase of urban population or energy consumed, the increase in Anthropogenic heat, etc. are considered as the cause. Now, subjects, such as LCC, are held although heat environmental measures, such as green roof, a green wall, Permeable paving, a Water retaining pavement, are studied. This research performed experimental research about the solar radiation shielding and the heat budget of a "reed screen" which are the natural vegetation recycling materials made from the reed which is a Water Purification Plants was performed, taking The viewpoint that a maintenance-free citizen participates easily by the viewpoint and low cost which use and preserve the natural features which the earth has into consideration.

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In large-sized recycling plants (with the processing capacity of 360 ton/day) where disassembled wooden wastes are chipped by crusher and reproduced into compress - formed board through their drying process, it is a tangible serious problem on-site that exhausted gas emitted from them causes erosion at impellers of the fan, duct and cyclone separator. In this report, we show the relation between operating conditions and erosion, which has been made clear by observing eroded impellers of the fan. To be concrete, velocity of air stream has a great influence on the development of erosion; the value of 30 m/s is one dividing point and has been proved to be a value of great importance. Regarding the difference of quality of materials, we have examined how the each one is affected by erosion, including the validity of data accumulated from erosion experiments at the laboratory. Herein, we make a report on the results of them as well.

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In this paper, we introduced "Quantity assessment of Automobile DfE", which was aimed at being able to reduce environmental impact and improve recycling rates. As its application, we introduced "Environmental Contribution Points System", which was aimed at being able to grow Eco Users and reduce CO2 emissions. We made a CO2 database about the effect of reducing environmental load, taking advantage of Automobile Recycled Parts or proper maintenance. The load estimates CO2 quantification and it is used as "Eco Points" for users, who will purchase recycled parts or send their cars for maintenance. For example, in order to promote Environmental Contribution Points, we collaborated with Green Point Club, which had 12 organizations. It installed our database to show the amount of CO2 reduction and Eco Points each recycled auto parts.

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These days, industrial waste recycling becomes more important and inevitable for environmental aspects. For example, the black powder called "Itomuka Zinc Calcine" which is produced in the recycling process of used dry-cell battery, has been unused for long period, because its effective reuse method has not been found. As for thermal power stations, some portion of clinker ash which is ordinarily produced from coal-fired boilers has not been wholly-recycled. Therefore, we tried to find effective utilization of two sintered porous materials, Itomuka Zinc Calcine and clinker ash, respectively. In the present study, water evaporation rates of those materials have been investigated on the point of thermal and physical properties. As a result, it is found that both sintered porous materials had higher evaporative performance, compared to the commercial water retention block.

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Now, the emission regulations of dioxins in exhaust gas from waste furnace and electric furnace for steel is 0.1ng- TEQ/Nm^3 or less (for new waste furnace that have incineration capacity of 4t/h or more) and 0.5 ng- TEQ/Nm^3 or less(for new electric furnace for steel) respectively. In addition, the demand of a new equipment that can remove the dioxins for lower than the regulation have risen. To meet such needs, our company developed a adsorbing tower packed with activated carbon (brand name : JFE Gasclean-DX) which is compact and have high removal performance of dioxins. In this article, we describe the feature of this equipment, and report the result of a high removal performance in commercial plant.

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JFE developed Twin-roll type indirect cooling equipment. The operating result shows that this method solves the conventional problems of space and water treatment. For a further cooling capacity, the structure of the roll has been improved. This paper shows the method of the thermal rating when the roll structure from winding type to spiral type. The roll surface temperature is corresponding to calculation result.

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JFE Engineering has developed the advanced stoker-type incineration system "JFE Hyper 21 Stoker system". It is equipped with some new technologies to meet requirement to the Municipal Solid Waste (WSW) incineration system; high efficiency of power generation, minimization of environmental pollution. This system was developed by a pilot plant test and an actual facility application test, and was applied to new incineration facility. As of April 2010, two facilities are operated and four facilities are under construction. We report operational aspects of the first facility, Kunisaki Clean Center (Hyogo prefecture: March-2009 completion).

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This paper describes several benefits of introducing energy recovery technologies into the present Russian municipal solid waste system on current energy system. A linear programming model MSWRUS has been developed in order to analyse proposed municipal solid waste (MSW) system, taking into account the energy, economic and environmental aspects. The objective function of the model is to minimize the net cost of the system, under several constraints. A case study in St.Petersburg, Russia, has been carried out for evaluation of proposed MSW system. The results show that the introduction of an optimal MSW treatment system has energy, environmental and economic benefits. The proposed integrated system can produce 6,500 TJ/year of heat or 516 GWh/year of electricity in average, which can be supplied to the existing energy system. In addition, the system can reduce the amount of landfilled waste from 89% to 20%, and reduce total system's CO_2 by 34%.

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The gasification power generation and the system of making the fuel and the chemical raw material from biomass are paid attention to as one of the environmentally friendly energy technology. The present study applies two step process of pyrolysis and gasification to biomass, and the aim of the study is to establish an efficient gasification method that can process various biomass. We report the effectiveness of an efficient gas cooling by the endothermic gasification reaction of the pyrolysis carbide and the high temperature flue gas in the latter part gasification furnace, which is confirmed with the bench scale experimental device. The gas cooling in hundreds of degrees was observed in any case in the carbide gasification reaction zone from the result of the gasification experiment that used various carbides, and it was confirmed to be able to achieve the gas cooling by using the gasification reaction without water spraying. The addition of steam improved effectively the gasification rate and the cold gas efficiency.

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The study aimed to obtain the environmental impact data in the demolition work of the civil structure by the field survey. From the results of examining environmental impact by demolition work and transportation, the amount of the CO2 exhaust in the RC bridge was a value that was larger than that of in the steel bridge. The selection of the method of the demolition showed that a big influence was exerted on the amount of the CO2 exhaust. Therefore, it is necessary to note it from the viewpoint of the environmental impact reduction to the selection of the industrial method. The longer the bridge of the amount per the unit length of the CO2 exhaust was, the smaller. Moreover, a tendency similar as for the amount per area of the unit bridge of the CO2 exhaust was shown.

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A number of accidents are happening in waste disposal facilities. Diversity of waste and advancement of recycling system are considered one of the reasons. Then, we construct and analyze database called ATHDB-all. It contains the accident, the trouble and the Hiyarihatto cases that happened in Japan. To make automatic safety education system by APT (Accident Prevention Training tool) with 3D-VR (Virtual Reality) technology by using the database of individual facilities are our point. We improve the collecting information tool by ICT(information communiation technology) and use this in three individual facilities. In addition, we constructed database in three. Using database, we developed the tool which can make automatically effective safety education program in each facility and used this tool in individual facilities.

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