Solid (fin) type vortex generators are known to be effective on suppressing flow separations and widely used at various fluid mechanical elements such as intakes or airfoils of airplanes. But the solid type generators themselves are the cause of extra flow drag. In this study we designed a blowing jet type vortex generator to realize smart control of flow separation. The present vortex generators are consisted of small jets on wall surface. Therefore, the present vortex generators are considered to minimize the extra drag compared to the solid type. The vortex generator was found to be able to generate a single longitudinal vortex near wall.

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Many buildings and apartments have water supply equipment. Most of them are settled just in a automatic water supply equipment (AWSE) along the corridor not in the pump room. In these cases, it is very important to make their noise and vibration lower. The sound isolation coyer is ordinary used for noise reduction, but it is not enough to reduce both of noise and vibration. In this research, through experiment and structural-acoustic coupled analysis, the main excitation source and radiation sound source are identified. Then the propagation path of sound and vibration are also clarified. From these results, an approach based on structural-acoustic coupled analysis for reducing noise and vibration is proposed through both experiment and analysis. Specifically, the natural frequencies and modes, vibration and radiation sound of each component and internal sound pressure distribution of water supply equipment was measured. An optimal arrangement of the sound insulation/ absorptive material was calculated by the numerical analysis.

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This paper describes a High SPL sound generated from banks of gas heater tubes in two ducts with an internal flow which are located parallel to each other and used in a boiler. In this experiment, two banks have tubes with diameter of 6mm. The sound pressure, the flow velocity and the acoustic damping of the duct are measured in order to clarify the generation mechanism of the High SPL sound. First, the relation between the velocity and the sound pressure level (SPL) is examined. Second, the acoustic modes of the ducts are calculated by FEM. Finally, the effect of various perforated baffle plates on the SPL is studied. As a result, it was found that the High SPL sound was caused by the interference between the vortex and acoustic field. And it was also clarified that the suppression effect of the baffle plate on the SPL is not only the destruction of the mode as is often said, but also the suppression of the vortex shedding due to the change of the local mode.

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Orifice plates are common devices in process plant piping systems. They can be used as pulsation suppression devices for reciprocating compressor and pressure reducing devices for gas services. It is known that the restriction orifices can cause high level tone noise in certain conditions and induce severe vibrations under high pressure ratio. In this study, the properties of the sound generated at the orifice plate in piping systems were investigated experimentally. The results show that the high tone noise is generated when the orifice thickness t/d is larger than 0.5 and the frequency of flow induced noise is close to the acoustic mode in orifice hole. Sound radiation from the orifice plate is dominant in low pressure ratio condition, and flow induced noise contribute much in high pressure ratio condition. The noise level for multi perforated plate is lower than that of single hole orifice in high pressure ratio condition, while flow rate of multi perforated plate is larger than that of single hole orifice. The validity of estimation method for sound power level by process condition was shown for multi perforated plate.

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It is described the simple prediction of the flow and the noise characteristics of the sirocco fan. The prediction is based on the method of the potential flow condition, which is provided with the source and the circle vortex in axisymmetric flow condition. The turbulent noise is estimated by the transformation to the linear cylinder. The prediction is examined in relating to the influences of diameter that is checked with the experiments. The scale of the separation near the front shroud is slightly increased with the diameter. The pressure is gradually decreased and the variation of it is well agreed with the experiment. The turbulent noise level is relatively good agreed to the experimental result. The validity of the simple prediction was obtained to the fluid and noise characteristics.

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In this study, the basic characteristics of the broad band noise (BBN) generated by an ultra-multi-blade sirocco fan were researched. In the impeller constituted by the forward curved blade such as sirocco fan, the flow between the blades is separated at the leading edge of the blade. In this case, it could be considered that the distribution of the pressure fluctuation made by the wake vortices in the share layer becomes a major factor for the sound pressure of the arbitrary observing point. As results of analyzed data of this experiment, it became clear that the characteristic of the fan noise was proportional to the index number K(=2.0〜3.0) of the flow rate coefficient. The predicted sound pressure of the BBN proposed in this study was proportional to the 2.6th power of the flow rate coefficient including the design point of the fan.

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This paper considers the minimization of the total acoustic power radiated from a duct opening. The power attenuation of sound absorption materials or barriers is relatively poor at low frequencies. Therefore, the authors propose active noise control algorithm in order to minimize the total acoustic power radiated from the duct opening by designing the duct opening, leading to the noise reduction in the entire area around the duct opening. In this study, the power reducing performance with this algorithm was verified by conducting the computer simulation.

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In 3-dimensional sound field, it is difficult to control noise in whole area. Instead of whole area control, the controlled area can be followed to people in that field by new approach proposed in this paper. In the proposed algorithm, FTF algorithm that has fast converging property is introduced to a direct adaptive algorithm which does not need an error path characteristic. A numerical simulation is carried out with a sound field that the error path changes during control. From the results of the simulations, the effectiveness of the proposed algorithm is shown.

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This report describes the active control systems for reducing floor impact noise. The control sysmtem is comprised of actively controlled modular thin plates, which wholly cover the surface of concrete slab structure in the ceiling, and in each of which the mechanical vibration is controlled independently with electro-magnetic actuators. In this report main componets of the control system, a light weight honeycomb panel, the actuators and the micro-computers, are presented. The final target is to commercialize the proposed active control system, but presently the development is going on.

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This paper describes two feedback control systems of active modular panel systems for insulating floor impact noise. The feedback control system is constructed with five sensors of the vibration acceleration, five actuators of the electro-magnetic type and the digital controller, which means MIMO control system basically. In order to decrease the computing load of the controller, the technique of decoupling the natural modes of vibration in the panel is applied. Individual controller is constructed for each decoupled natural mode. We investigate a suitable controller for the micro computer by comparing with control results of two control systems: robust feedback and output feedback.

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The current state of low-frequency noise radiated from a high-speed train was examined through field experiment based on the manual for measuring low-frequency noise which was issued by the Ministry of the Environment of Japan in October 2000. The measurements were done at a Shinkasen tunnel portal and at a Shinkansen viaduct in an open section by using a low-frequency sound pressure level meter (NA-18A) manufactured by Rion Co., Ltd. From the results obtained are the G-weighted sound pressure level, spectra of 1/3 octave band sound pressure level, and dependency of the maximum G-weighted sound pressure level on train velocity.

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MAGLEV R&D including its running tests is in progress in Yamanashi Test Line (hereafter referred to YTL) to be practical system ever. This paper discusses how environmental effect can be mitigated by the technique arranged along YTL where various data of noise and ground vibration are collected.

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This paper introduces a new concept which can easily reduce sound reflection coefficient at a duct open end. When we make a duct side wall next to open end of appropriate perforated plate or porous material, sound reflection at that open end is remarkably reduced and the radiated sound is also reduced. Here this phenomenon is analyzed theoretically and proved experimentally. This technique is useful and applicable to reduce acoustic resonant intensity in the duct such as stacks of plants, mufflers of engines and so on. As the result, it can reduce the radiating sound from the duct open end.

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Sound Absorption of Granular Material had not evaluated, because it seems that the sound absorption effect of granular material is very small. But it is well known that the noise levels in train tunnels are on the increase caused by changes of railways from ballast to slab. This study tries to measure sound absorption effects and airflow resistances and to evaluate the horizontal incident sound absorptions of granular materials. The sound absorption of granular materials increases according to the airflow resistances. The tendency of it is the same with tendencies of porous materials. It is confirmed that the sound absorption effects paved with granular materials in the test pipe.

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Sound absorbing characteristics for perforated panel at ultra low frequency were studied. Principle of sound absorption of perforated panel has two mechanisms. One is friction loss in a flow of cylindrical tube, which is proportional to particle velocity in a hole. The other is pressure loss as orifice, which is proportional to square of particle velocity in a hole. Therefore sound absorbing characteristics are depend on sound particle velocity and sound pressure level. We applied calculation method to predict the sound absorbing characteristics of perforated panel in ultra low frequency region by using transfer matrix method and measured those at ultra low frequency using two-microphone method. Calculated values are in good agreement with measured values.

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Many papers on low frequency noise describe the evaluation on pure tone and stationary sound. The sounds of moving cars or trains are not pure tones and not stationary. This paper describes the method of evaluation of low frequency noise of moving source.

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A rest room is required in comfortable living space. There's a tank less toilet going around because a space is excluded recently. But toilet jet that is specific for tank less toilet becomes a problem for the living environment noise. So this paper describes the improvement of sound quality of toilet jet. An acrylic board model is made for taking a picture of the flushing mechanism by a high-speed video camera. It is found that the jet noise generates many bubbles involved in water current, and in order to reduce noise, the form of a nozzle is changed. For the result is evaluated, the relationship between sound quality of toilet jet and human sensation is investigated by using sound metrics and vital data.

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This paper describes our proposal concerning the quantitative evaluation process to the acoustic environment, working efficiency and human impression for various industrial working areas based on the following analysis. (1)WWL score can be evaluated by NASA-TLX. (2)WWL score is changed by the condition of acoustic environment. (3)Action pattern of human has a relation with WWL score for mental and physical demand. (4)Working speed depends on WWL score. (5)Relation between the working speed and WWL score has a difference by action pattern. (6)Durability of working can be judged based on the result of evaluation for human impression.

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The purpose of this study is to examine the condition of "comfortable swinging". The swinging of the low frequency seems to be sensed in the semicircular canals which sense the posture. Therefore, an equipment is developed for measuring the three-axial acceleration on the ear where is near the semicircular canals. Then, acceleration on the ear of person swung by the active swing chair realizing the comfortable swing and by the active rocking chair changing the driving force with heartbeat fluctuation is measured. It is clarified that the power spectrum of the envelope of acceleration waveform shows the relationship of "1/f". Next, the acceleration on the ear of person riding a pickup truck with hard suspension, comfortable car with soft suspension and comfortable limited express train is measured. The deference between the power spectrum of the envelope of acceleration sensed comfortable and one sensed uncomfortable is clarified.

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A human being laughs in every day life when happy, and a facial expression changes unconsciously. It is thought that the expression has close relation to emotion. The facial expression is more intelligibly than the expression by word, and can convey a delicate nuance when introducing emotion. Communication with a different foreigner is possible by a facial expression and a gesture. In this way, the role that a facial expression serves as by communidation is very big. The aim of this study is to improve a mental condition by the intentionally modified facial expression. The final aim is application to a field of the medical welfare, hi this article, quantitative evaluation method is utilized for the evaluation of emotion by using electroencephalogram. The frequency fluctuation of brain waves which is said that individual difference is small is focused. The first step of this article, the evaluation method of emotion is proposed. And next step, smile which typically pleasant is focused. Optical smile induced pleasant emotion is found.

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This report deals with an experimental method for estimating sound pressure level from the acoustical enclosures. By using a vibro-acoustic reciprocity technique, we measured the acoustic transfer function for sound radiation from the opening and the vibrating components. And we measured volume velocity of each component as the sound source. Especially in case of the opening, we calculated the volume velocity by using the measured pressure level and theoretical radiation impedance. Eventually, sound pressure level from the acoustical enclosures are estimated by using the measured acoustic transfer functions and the volume velocity of each components. The comparisons were made between predicting results using the reciprocal technique and directly measuring results. Agreement is fairly good and it suggests that this method can be used to evaluate the sound pressure level from the acoustical enclosures.

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It is important to reduce a noise along railway lines not only for high-speed Shinkansen (220-300km/h) but also conventional railways (below 160km/h). The noise of the narrow-gauge lines is composed of rolling noise and traction motor cooling fan noise. This paper describes the effect of wheel shape on rolling noise. We measured the noise by using a one-dimensional horizontal microphone array and did impact testing of Type NA wheel with a doubly curved web. The noise of Type NA wheel with a doubly curved wheel is larger than that of Type A wheel with a curved wheel at about l,250Hz and l,900Hz. The results of wheel characterization measurement by using an impulse hammer show that the rim of Type NA wheel vibrates radially with two nodal diameters with the web vibrating axially at l,250Hz.

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To reduce the interior noise in high-speed trains, we have built several interior noise simulation models based on statistical energy analysis and boundary element analysis. By comparing the noise calculated using these models with the measured interior noise in train cars, running through various sections at various speeds, we have confirmed the models is accurate within 1.5 dB for the overall noise level We therefore used them to evaluate contribution factors of the interior panel radiation to the interior noise and to evaluate the effectiveness of several countermeasures. This procedure could be used to design optimal structures for large and quiet passenger cabins.

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In this paper, it aimed at the thing to propose the prediction method of noise and vibration in a ferroconcrete structure by using Statistical Energy Analysis (SEA) from test/analysis Frequency Response Function (FRF) data. This method carries out by the following process; (1)The SEA parameters were calculated by test/analysis FRF data, (2)Estimated energy responses between subsystems were calculated by using the SEA parameters, (3)Predicted velocity responses were estimated in a subsystem, and (4)Predicted velocity converts to sound pressure. As a result, sound pressures could be predicted by this method with few errors.

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Auditory signals in automobiles function important roles such as danger alarm, operation feedback, malfunction warning, etc. However, there were not enough studies on the design of auditory signals in automobiles. In the present study, the relationship between the acoustic properties and auditory impression of reverse gear car alarm-sounds were examined. Fundamental frequency of the appropriate sounds for reverse gear car-alarm is 1k to 2kHz. Their spectral centroid is lower than 3.5kHz. Reverse gear alarm-sounds are intermittent sounds. The duration of sound and inter onset interval of the appropriate alarm is 500 to 700 ms. We obtained systematic knowledge to design appropriate and comfortable sounds for reverse gear car alarm.

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A questionnaire survey was conducted to evaluate the economic value of sound quality of hairdryers using contingent valuation method. In this experiment, two stimuli inducing the unpleasant and pleasant impressions were presented to subjects based on the assumption that the former sound was emitted from the original product and the latter from the product with improved sound quality. Subjects were asked how much extra they would pay for the improved product in addition to the price of the original product. The questionnaire also sought personal attributes of each subject such as age, annual income, subjects' experience of being distracted by the noise of hairdryer, points checked when buying roducts: performance, price, etc. The obtained results were applied to a logistic regression analysis. Consequently, the price for the improvement of sound quality was estimated as being 469 Japanese yen, which is approximately equivalent to 12 % of the original price of a hairdryer.

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A system for development of sporty interior sound during acceleration was achieved that supports evaluation of interior sound quality, definition of interior sound target and definition of intake noise target. A technique defining an intake noise target was developed with a method, which simplifies the interior sound by separating into three components: a component caused by intake orifice noise, a component caused by exhaust noise and the background noise. An intake noise target is calculated with an interior sound target, a background noise of an original interior sound and a transfer function from an intake orifice to the interior.

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This paper describes a large-scale automotive sound quality evaluation database created by the JSAE Sound Quality Evaluation Research Technical Committee. This database was created by conducting subjective evaluation tests under controlled conditions and using common procedures. It involves the subjective evaluation data for the interior sounds of accelerating gasoline passenger cars by 101 Japanese test subjects, and for the exterior sounds of diesel trucks at idle by 143 Japanese test subjects. Moreover, the subjects' profiles data (gender, age, sound quality specialists, and so on) are included. We can carry out various analyses on automotive sound quality and some effective results for improvements of sound quality can be obtained by using this database.

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Different from conventional loudspeakers, a parametric loudspeaker system uses the nonlinear properties of air to produce audible sound within the air using a set of ultrasonic waves. The parametric loudspeaker system has many benefits, including controlled sharp directivity, projection of audio sound over long distances while maintaining intelligibility, use of thin non-magnetic emitters. This prospective loudspeaker system is drawing special attention as a next-generation acoustic transducer among acoustic engineers in the world. This report outlines the parametric loudspeaker system in terms of historical background, basic principle and configuration, trends on research and development, patents, current products, and field of application.

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Parametric loudspeakers can deliver sound to a defined spot in a room by producing waves that focus like a laser beam. The high-directivity sound system, based on this theory, has a wide area of prospective applications including voice guidance system for exhibition halls and public facilities. This report outlines the configuration of our high-directivity sound system and some application examples.

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In solving the noise problem in the factories and complex machineries, the first necessary step for the effective improvement is to exactly know the properties of the noise; loudness, frequencies and location of them. The purpose of this work is to develop a ready-to-use noise source visualization system. This system consists of a foldable handy microphone array and a portable computer with source analyzing software. In order to realize a real-time analysis, we have improved the hardware and optimized the software code for noise source localization. By superposing the captured image on analyzed noise source map, we can "visually" understand where the noise comes from. This paper describes the outline of this system and some application results.

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Japan aerospace exploration agency (JAXA) deals with unique approach of simulating aircraft noise and localizing moving source. It is composed of a microphone array and a jet propulsion unmanned aerial vehicle (JUAV). The microphone array on a runway combined with laser sensors, global positioning system (GPS), high-speed camera and so on enables the source localization of flying JUAVs. The JUAV were specially fabricated for simulating noise source such as engine, fuselage, high lift devices, landing gear and other probable aero-acoustic interference. This paper summarizes both the microphone array system and JUAVs developed in recent years.

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In order to detect acoustic waves in the flows without disturbing them, a new type of microphone called coiled optical fiber microphone is proposed. It is found that the frequency shift of lights through curved optical paths is proportional to the acoustic pressure amplitudes. Based on the principle of the frequency shift, therefore, acoustic measurements in flows become possible, provided that the noises from solids can be properly isolated. The new optical fiber microphone was embedded on the surface of an airfoil and its performance test was done in a wind tunnel. Results are reported in this paper.

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This paper, consisting of the following three sections, describes the current state of the evaluation of traffic noise and the countermeasure applied to each traffic facility. First, in addition to the outline of noise effect, the limits and guidelines for environmental noise proposed by EPA and WHO to maintain a good living environment arc introduced. Second, residents' complaints and reactions to various traffic noises, the legal system for environmental noise in Japan, the characteristics of noise limits and standards, and the result of comparison of them using L_<Aeq> as a noise index are reported. Finally, the outline of countermeasure developed by each traffic facility and the degree of achievement of noise reduction are introduced.

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JR East Company and Takenaka Coporation has developed the world's first suspended vibration and seismic isolation system. This system utilizes the space beneath railway viaduct, dramatically reduces train noise vibration and earthquake movement, and maintains or enhances the earthquake resistance of overhead railway bridges. Completion in February 2004 of the Hotel Dream Gate Maihama beneath overhead lines at JR East Maihama Station marks the system's first practical application. The system suspends the building from an overhead railway bridge using suspension materials of differing vibration properties, thus capitalizing on the interconnected damping effect by which the different materials cancel out each other's vibration to maintain and enhance the earthquake resistance of the overhead bridge. The technique paves the way for new development projects utilizing space under railway lines and will enhance asset values while contributing enormously to the revitalization of Japan's cities.

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While road traffic noise level is decreasing in Japan, the people living along trunk roads still have complaint against traffic noise. According to an official investigation, main target of the complaint is motorcycle. It is supposed that there are three reasons why motorcycle sound is annoying, which are increase in the number of motorcycles equipped with replacement muffler, increase in the number of imported motorcycles, and specialty of motorcycle sound quality. To solve this problem, administrative measures, technical measures and psychological measures are necessary. In the technical measures, improvement of noise measurement accuracy and evaluation of sound quality are important. On the other side, it is pointed out that electric vehicle is dangerous for pedestrians because of its quietness. It is difficult to improve vehicle sound quality and to solve electric vehicle issue by mechanical means only. Therefore electrical means will be necessary.

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This paper presents dynamic simulation of a running 2 wheels cirive robot. Motion of most autonomous 2 wheels drive robots is a running along given trajectory in advance or a running by combination of straight run and turning to random direction. Perhaps it is to say theses robots are not convenient at some points for users because the motion of the robots cannot be predicted for users under running. Moreover, it may be able to say that noise under the robots are running is out of consideration in the design stage in most cases. Therefore, an autonomous 2 wheels drive robot that is controlled by teach and playback manner and run as constant speed as possible for noise reductic a under running is proposed. The system model of the robot was built and the running performance was verified by simulations.

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Coincidence effect is important phenomena for development of sound insulation structures. Theoretical understanding concerning coincidence effect of infinite plate has been established, but detailed examination of a finite plate is not enough. In this paper, first of all, coincidence phenomena of the square plate which is excited by sound pressure from a point source is visualized by using acoust - structural coupled analysis technique, and the feature of coincidence phenomena of finite plate is explained. And then it is ascertained that non-coupled analysis of the plate excited by mechanical force which is more simple and more easy than coupled analysis of the plate excited by sound pressure is available for simulation of coincidence effect of finite plate.

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As to the design process of a bell, a trial-design is performed depending on the experience of a designer or the past design data. If the trial design is not fit with the target conditions, corrections of the design should be repeated for several times, which takes too much time and cost. Numerical model is made by computer to make the corrections more speedy and efficient. The appropriateness of the numerical model can be controlled by structural modification. Prediction and adjustment of the tone of the bell can be performed in a short time, then the target value can also be carried out.

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A new CFD-code "3d-MSW" to predict the waste bed combustion in the stoker-type Municipal Solid Waste Incinerators (MSWI) was developed. 3d-MSW was validated by comparison with the combustion tests in a pilot incinerator. The calculation results could predict the waste bed combustion under not only normal air but also oxygen enrichment air. Grate moving velocity in an actual incinerator was also evaluated by applying the new code. 3d-MSW could present the influence of the grate moving velocity on gas temperature and carbon monoxide concentration. 3d-MSW is very useful as a simulation tool for understanding the phenomenon of the waste bed combustion in the stoker-type MSWI.

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Measures such as low air-ratio combustion and exhaust gas recirculation have become the subject of a great deal of attention with a view to reducing the amount of environment impacting substances from the waste incineration process, and also to making the most effective use of energy. However, it has been understood there would be considerable difficulty utilizing low air-ratio combustion on the conventional grate furnace. The application of high-temperature air combustion technology for enhancing sound combustibility could provide solutions to these problems and it was studied before now. A practical test was conducted at a 105ton/day municipal solid waste stoker type incineration plant. The test demonstrated that stable low air-ratio combustion operation is possible at the stoichiometry of 1.3 with EGR (Exhaust Gas Recirculation) and high temperature air combustion technology resulting in a 17% decrease in flue gas flow, an energy efficiency improvement of 10%, and a significant reduction of toxic products emission when compared with a stoichiometry of 1.6 as conventional method.

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New MSWI system have been demonstrated. The combustion technique using the addition of oxygen to combustion air and flue gas recirculation ( FGR ) from outlet of bag filter were employed in this demonstration test to evaluate influence on solid combustion, emission of carbon monoxide (CO), nitrogen oxide (NOx) and dioxins (DXNs). The bench-scale test has been conducted to compare with the demonstration test. The technique enhanced combustion rate of solid waste and decreased ignition loss of residue, that showed the decrease of residence time or reduction of the combuster length. Emissions of NOx and DXNs were reduced by technique.

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We have developed the new MSW incineration system that is characterized by the combustion using the addition of oxygen to combustion air and flue gas recirculation ( FOR ) from outlet of bag filter. The tests to optimize operate condition were carried out in bench-scale facility. Costs, solid combustion, dioxin emission and NOx emission were evaluation items to optimize operate condition. It was found out the optimized oxygen concentration in combustion air to decrease costs, promote solid combustion and repress dioxin emission. However, optimized FGR condition to repress dioxin and NOx emission was not found out. Effects of FGR are influenced by the furnace geometry and combustion state. So optimized FGR conditions should be examined in each facility.

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The first Water-cooled grates system, the most important key technology for Next generation stoker incinerator, was applied to an existing commercial waste incineration plant in Japan to demonstrate its operation performance Following results were confirmed for one-year incineration operation. (1)Surface temperature of the gates could be kept less than 70 degree-C and the long term stabilized incineration was confirmed by a sufficient cooling effect. (2)Abrasion loss of the gates was less than 0.5 mm for one-year operation and excellent durability was confirmed. (3)Stable operation with 8% O2 concentration in the flue gas at SCR outlet was confirmed with flue gas recirculation. (4)CO concentration in the flue gas could be kept at a low level sufficiently by mixing effect of flue gas recirculation as a part of secondary combustion air. (5)15% reduction of the flue gas emission was confirmed in case of flue gas recirculation.

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The fluidized'bed gasification and melting system for MSW (capacity: 30tons/day×2) has been operated for two years. This plant has a radiate heat exchanger for combustion air. This paper describes recent operation results of fluidized-bed gasification and melting system in this plant.

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Distributed system for gasification and power generation has been developed for combustible solid wastes. Based on this technology development, small-scaled municipal wastes disposal facility which capacity is about 20ton/day is designed and constructed. In this facility, mixture of MSW from the town which population is lower than 10,000 and biomass fuel (meat and bone meal of cow) are fed to gasifier combined with melting furnace to generate pyrolysis gas. The pyrolysis gas is reformed, cooled and purified into fuel gas utilized for dual-fueled diesel engine with BDF(Bio Diesel Fuel) based liquid fuel to generate electrical power. In this paper, the technology of gasification and reforming, design concept of this facility, and preliminary data during trial operations are described.

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