Mechanisms of airflow from a developer unit was examined by visualization techniques. An airflow inside developer unit was closely related the toner cloud phenomenon. But the airflow between magnetic sleeve and electrophotoconducter drum was hardly visualized, because the flow structure was complicated.
Experimental equipment of developer unit was constructed to obtain the clearer visualization image of the airflow. And using image-processing technique, characteristics of the flow structure became cleared. As the result, it showed how an airflow inside the developer unit changed by a rotation speed of the photo conducter drum and a movement of magnetic career brush on a sleeve.

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A flow around rotating blades of micro wind turbine was visualized and measured by PIV technique. The diameter of micro wind turbine is 500 mm. This micro wind turbine is a unit of integrated wind energy system. The micro turbine has features as large solidity and long chord length. The measurement was carried out with 3 × 1.8 m² wind tunnel at the wind speed in the range from 3 to 10 m/sec. Twin YAG laser was employed to the measurement. An approaching flow to the wind turbine and its wake were visualized with a phase locked measurement system. Stream lines in an approaching flow was discussed for the design of the blade in the visualized two-dimensional plane. A wake flow of the wind turbines was examined for the improvement and noise reduction of this system. It is found that the wake flow was disturbed and large scale vortices was observed in all wind speed condition.

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For the analysis of the laminar separated flow around the NACA symmetrical airfoil in transition region of Reynolds number, it is a problem that the flow separation and the development of the shear layer are sensitive to the flow conditions very much. Hence, we made the matching of laminar boundary layer theory with vortex method. We also proposed a new scheme that the vorticity field in the shear layer is decided from the Gaussian vorticity distribution and the no-slip condition was adopted by setting diffusive and productive vortices. We made clear that the flow separation is estimated with laminar boundary layer theory. And Computational results around the body showed good agreement with the experimental ones.

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The relative velocity field in the impeller of the ultracompact centrifugal pump developed as an artificial heart has been investigated by high speed videography and particle image velocimetry. The transient motion of the velocity field relative to the rotating impeller blades has been clearly visualized by the use of image rotating system composed of the beam splitter and the right angle prism. The flow field in a passage exhibited strongly unsteady motion. The secondary flows developed in the passage were considered to play an important role in antithrombogenicity of the pump which depended upon the shear stresses acting on the blood contacting surface.

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In this paper we will describe some of the research done in using wavelet transforms for pattern recognition at the Centre for Research in Pattern Recognition and Machine Intelligence at Concordia University. This includes road signs recognition, face detection and recognition, oriental characters recognition, hand-written numerals and characters, image compression, and image de-noising, etc. We have developed a new metric called the Hellinger-Kakutani metric for measuring the distance between two descriptors for classification. This metric is filter-invariant, hence can be used on noisy images.

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A new concept is introduced to extract the essential and distinct characteristics of images by means of smart image processing. The key idea is to introduce the eigen pattern, which consists of intensity, tone and color component of a digital image.
A color graphics image on two-dimensional plane is represented by a set of the pixels containing the red, green and blue color information, and represented by geometrical arrangement of intensity, tone and color component. Thereby, color graphics images depend on their resolution and the spatial position on the screen.
The eigen pattern removes the location, angle and size information on the screen, and extracts the essential characteristics of images. We apply the notion of eigen pattern to image cognition by means of smart image processing. As a result, we have succeeded in cognizing images exactly.

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Wavelet multi-resolution method was applied to analyze the interview data concerning with the marriage and vocation views of the traditional and non-traditional Japanese young men having conservatism as well as progressivism. The wavelet multi-resolution analysis is capable of extracting and discussing the detailed information of various levels on the marriage and vocation views. Examination of each of the multi-resolution levels suggests that they experience a transition period, which is found in not only marriage but also vocation viewpoints. Furthermore, It is clarified that the vocation view of tradition and non-tradition mixture is similar to that of tradition one.

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This experimental study aims at investigating the influence of the condensed particle in the free turbulent shear layer under the jet diffusion process. Chilling dry air is discharged from a round nozzle into the high humidity environment. The air issues from the round nozzle of 10 mm in diameter into the measuring section. For velocity measurement, the laser LDV is used as the forward-scattering mode. It is observed from the visualization photograph that that condensed particles exists around the free shear layer. From the measurement the particle increase and spreads toward surroundings as the humidity rises. The mean velocity and fluctuating velocity decrease as the increase of condensed particle number. The characteristics of condensation jet are denoted from the above measurement results.

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The turbulent structures of various scales behind the solid and porous wake-generating bodies with the same characteristic dimension have been studies by the wavelet vector multi-resolution technique. Making a comparison of instantaneous sectional streamlines of various scales obtained with each wake generator, it was found that the behavior of large- and intermediate-scale structures in wakes depends on the initial conditions and the small-scale structures is independent of the initial conditions. The most significant contribution to Reynolds stress and turbulent energy appears to come from the large-scale and rib-like structures in the cylinder wake. In the screen wake, however, only the large-scale structure exhibits more contribution.

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The smart visualized image processing was applied to PIV images for improving the time resolution. PIV images consist of a set of sequentially discretized images in time domain. The smart visualized image processing can convert the discretized PIV images into continuous images by using Helmholtz equation. Therefore, the higher time resolution of PIV images can be obtained. It can say that the smart visualized image processing technique is effective in PIV system and flow visualization.

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Particle distribution in a pipeline has been clearly visualized by a combination of capacitance computed tome graphy and comvolution processing. The particle distribution just after the plugging point gets partial on a cross section. In the pipeline, clay attached inside in order to simulate near plugging. The CT obtains the capacitance between 12 electrodes distributed around the outside of the pipeline. The particle and air distributions can be separated because of individual permittivity by the reconstruction technique. The technique calculates the permittivity distribution on the cross section from the capacitance values by an iterative method of inverse problem.

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In order to extract the distinct difference between the skillful and novice tennis players stroke forms, we have applied the Fourier-wavelets transform method to the sequential stroke images. According to our analysis, it has been revealed that a skillful tournament player's form with extending knee and flexing trunks motions yields higher accelerating racket speed than those of novice. Fourier-wavelets transform method is composed of two major steps : Fourier transform is used to correct positioning differences among the sequential images during tennis strokes. After that, local distinguished differences among them are extracted by means of wavelets multi-resolution analysis. Thereby, Fourier-wavelets transform method makes it possible to extract the differences between the skillful and novice tennis players, while conventional method is subjective one based on the judgement by the human eyes.
Thus, in the present paper, it is revealed that our proposed approach has a considerable possibility to extract the differences between the skillful and novice tennis players without any professional human observations.

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Previously, in order to carry out the three-dimensional magnetic field analysis in a most efficient manner, we proposed the theory of modern magnetic circuits based on finite elements discretization. This makes it possible to implement the three-dimensional magnetic field computation in a quite efficient manner similar to those of the conventional magnetic circuit theory. In the present paper, we try to apply the wavelet transform to a magnetic flux distribution in order to represent it by small computational effort. As a result, it is shown that the wavelet transform yields a fairly good distribution from small computation.

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Animation is divided into static and dynamic images by the modal-wavelets. The modal-wavelet transform is proposed as one of the discrete wavelets derived from a modal analysis to a potential field. One of the distinguished features is that the modal-wavelet transform is free from the number of the elements composing target data. It is useful to handle animation data having high resolution as well as large number of frames. This new method is applied to visualized eddy flow animation in order to divide it into the static and dynamic images. As a result of the modal-wavelet analysis, the core of eddy flow can be extracted in the separated static image.

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Internet is exponentially developed on digital society. As result, we can get easily literacy work without. permission from author. The infringement of copyright is carry weight worthy of remarkable problem in network society. Digital watermark is one of the recently technology for preventing form infringement of the copyright for digital data of the original content. We have presented a one of method of digital watermark for the purpose of copyright protection by frequency domain through wavelets transform.

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This paper proposes a visualizing methodology to the current distributions on a printed circuit board by means of an inverse source approach.
At first, we carry out numerical simulation employing loop current model. As a result, it is revealed that any of the magnetic field components lead to an exact current distribution.
Second, we carry out an experimental verification of our method. However, the most dominant magnetic field component leads to a good current distribution, but minor magnetic components lead to the noisy current distributions.
Finally, the most dominant magnetic fields measured at the both upper and bottom sides of a printed circuit board lead to the fairly good current distributions. In order to extract the common currents between the current distributions independently computed from upper and bottom major magnetic fields are convolved. This leads to an exact current distribution on a printed circuit board.
Thus, we have succeeded in visualizing the current distribution on a printed circuit board.

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The multi-resolution analysis of wavelets has been applied to clarify the differences between Japanese and Western cultures through the style analysis of Buddhist and Christian scriptures : The Tanni sho and Book of John.
The Tanni sho is question answer-leadership oriented, and Book of John command oriented. The question-and-answer style in the Buddhist book seemed to have played some role in creating the relativist cultural climate, while the command dominated style in Book of John goes hand in glove with the cultural absolutism in the West.

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Visualization of interactive mutation inside reader's mind while reading a book has been studied by employing the discrete wavelet analysis. Readers are attracted to the book world as if they are. However, it is difficult for the readers to keep concentrating their own minds on the book world. Since reading a book is to switch the book and real worlds constructed by some layers of the story, then this sometimes confuses the readers. The layers are classified into two types. One is a real world in the story as character's life. The other one is a virtual world representing character's thoughts or recollections. To clarify the effects of these layers, movement among them is visualized by the wavelet multi-resolution analysis. In the present paper, Ekuni's novel, Rakka suru Yuhgata, is studied to extract the opportunities when the text lets the readers move from the book to real worlds.

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Cognition of the time domain signals has been mostly depended on the experiences of the skillful observers. We have proposed a new methodology in order to carry out for human voice cognition. Since the human voice depends on each of the persons even if the same word pronouncing, then it is essentially accompanying the data based learning process.
To overcome this difficulty, in this paper, we apply the image cognition technology of the human voice to the cognition of magnetic sensor signals. The time domain signals are converted into the three-dimensional image data by means of the modified Lissajous diagram.
Further we have tried to compress the three-dimensional Lissajous diagram by means of the discrete wavelet transform. As the result, it is revealed that the wavelet transform makes it possible to reduce the database quantities.

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We try to control the magnetic field distribution at a flat square surface by means of the multi-layered flat exciting coils in order to work out a magnetic domain-observing instrument under the controlled magnetic field distributions. Our designing methodology is reduced into solving for an ill-posed inverse problem. When we solve an ill-posed inverse problem, it is possible to apply the Generalized Vector Sampled Pattern Matching (GVSPM, in short) method. In order to reveal the fitness between the desired and generated magnetic field distributions, it is essential to use an objective function defined by the multi-resolution analysis of a discrete wavelet transform. As a result, we have confirmed that the desired magnetic field distribution could be realized by our method.

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In the present paper, we propose a method of analysis for the magnetic sensor signals. Based on the physical characteristic value such as a time constant of the electric circuit, our methodology tries to work out an equivalent characteristic value reflecting the physical property of the target metallic material. Our smart magnetic sensor developing is to recognize a datum from the signal database. This is applied to the space domain signal recognition. Further, this paper reports that our equivalent characteristic value can be compressed in a quite small data quantity by means of the wavelets.

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Microfluidics is recent topics in various fields of engineering and science, such as micro-circulation in living body, flow through micro-channel for medical use, micro-flow mixing, micro-jet, flow in porous media, flow around electronic device, flow around micro-machine, chemical reaction, molecular design and so on. In micro-flow analysis, physical characteristics, which are particular to the micro-flow, must be considered. And also experimental method is different from it for general flow problems. Micro-PIV is useful to velocity field measurements of micro-flow phenomena, however, practical technique of it has not been established in detail. In this report, velocity distribution of flow through a micro-channel is measured by using micro-PIV system based on macro-zoom lens system, and depth-wise spatial resolution of the measurement is discussed.

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Drag-reducing turbulent flows of dilute polymer solution are measured using particle tracking velocimetry (PTV). The measurements are done in a micro channel 2 mm in wall-to-wall distance for the Reynolds numbers of about 300 and 10, 000. A double-pulsed Nd : YAG laser is used to illuminate 0.8μ-diameter acrylic tracer particles. It is confirmed that the turbulent drag reduction in polymer solution (i.e., Toms effect) becomes more pronounced in small conduits like the present micro channel than in other larger channels and pipes. The mean velocity profile in drag-reducing flows looks like the laminar velocity profile. The turbulence statistics measured in drag-reducing flows have shown that the streamwise and wall-normal velocity fluctuations, when normalized with the friction velocity, are approximately of the same magnitude as those in pure water flows but that the Reynolds stress almost vanishes. Separate PIV measurements indicate that the presence of elongated structures of streamwise velocity fluctuations contributing little to the generation of the Reynolds stress is the reason for the measured turbulence characteristics in the drag-reducing micro channel flows

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The authors try to measure the velocity distribution of water flows in a micro channel (0.4 millimeters width and 0.1 millimeters depth rectangular section) by PTV. Under the room temperature, water containing 2μ-diameter tracer particles flows vertically downward in a channel. High-resolution video camera is used for grabbing images of tracer particles with illumination of a metal-halide lamp. The depth of focus is 0.04 millimeters and the focus point is adjusted at the center of the channel. The velocity distribution of micro channel flow can be obtained by PTV analysis. And the case that there is a small air bubble on the one-sided wall of a channel is also observed. In this case, the velocity of water nearby the bubble is larger than that nearby the solid wall.

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This paper describes on the mixing and the chemical reaction of two fluids in the enlarged model of a micro fluidic device, which enhances the chemical reaction by its unique shape. We could easily visualize the mixing of two fluids with different color, red and blue. We also visualized the chemical reaction using luciferin-luciferase reaction, which generates green light by the reaction. The system of a CCD camera mounted on a microscope could observe the light and record it.

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In development process of electrophotography, charged toner particles move to form image by the electrostatic force in a micro-gap between photoreceptor drum and development roller. To improve image quality and prevent image defects, it is important to clarify the motion of toner particles and to study the effects of electric field. In the present study, PIV system is used to measure the velocity of toner particles and the measured results were discussed comparing with the calculated electric field. It was confirmed that the velocity of toner particles increased with increasing electric field intensity. These results show the usefulness of PIV system to measure the motion of toner particles in development process.

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Thermal behavior and cluster formation of ferromagnetic particles in magnetic fluids were investigated using an optical microscope system and PTV image data processing system. Real-time visualization of the Brownian motion and the chain-like cluster formation of three types of particles were carried out under a magnetic field. The influence of the magnetic field intensity and the temperature variation on cluster formation of ferromagnetic particles was investigated.

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A method is described for measuring disturbance velocity fields induced by N spherical particles rising in a quiescent fluid at low Reynolds number. The method requires information for the particle configuration and the instantaneous flow field at the same time. The particle location was measured with stereoscopic cameras, and induced velocity fields were obtained by using a particle image velocimetry. Disturbance velocity fields were evaluated at a plane, which was defined as the difference between the real velocity fields and the superposition of Stokes solutions for each rising sphere at known location. Large disturbance velocities were observed near the particles, and their directions were opposite to the rising motion of the spheres.

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Molecular flow induced by intermolecular potential gradient between solid and fluid was analyzed by a MD method. Platinum (Pt) and xenon (Xe) were used as solid and fluid respectively. The number of Xe molecules was 100 and that of Pt atoms composing walls of nano-channel was 2400. The wall temperature was fixed at 300K. It was found that a longitudinal rotating flow in the nano-channel could be driven by the potential gradient.

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To investigate wind environment in and around structures or wind loads acting on those surfaces, a flow visualization technique is very useful method. Recently, this technique is developing with the advance of digital image processing techniques and various facilities such as a digital video camera, a laser illumination device, a seeding generator of tracer particle and a computer system. Hence, the flow visualization techniques are used frequently in the architectural and civil engineering fields to measure the complicated flow and pressure fields in and around structures. This paper outlines the flow visualization techniques in the architectural and civil engineering fields and introduces examples of those applications.

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Rain-wind induced cable vibration is one of serious problem on design of cable-stayed bridges. This vibration usually occurs at particular high reduced wind velocity regions under raining condition. The generation mechanism of this vibration is rather complicated since the cable's attitude against wind is inclined, and then there are strong three-dimensional fluids characteristics around the inclined cable. Also, a water rivulet is formed on the cable surface. To understand this phenomenon, the flow field around an inclined cable was investigated by wind tunnel tests. Flow visualization tests around inclined cable model and a series of wind tunnel tests measuring its unsteady aerodynamic force and the unsteady wind fluctuation at its wake were conducted. Then, it becomes clear that there are three-dimensional interactions related to Karman vortex and the effects of water rivulet, and the wind turbulence may be significant factors of this vibration.

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When an incident flow attacks to structures with a flat roof at an oblique angle, conical vortices are produced on the roof. The severe suctions are appeared near the windward vertex by the conical vortices. In the case of the delta wing, the steady suctions occur because of the stability of the conical vortices. However, the wind pressures on the roof of the box-type structures are fluctuating, differently from the case of the delta wing. This paper presents the flow patterns on the flat roof of several models with a square section by means of a flow visualization with a laser sheet and a strobe light. The characteristics of the fluctuating wind pressures are also investigated by Proper Orthogonal Decomposition (POD). Based on the results of the flow visualization and the POD analysis, the relations of the conical vortices and the fluctuating wind pressures are studied.

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A convenient technique for evaluating the wind environment around buildings in wind tunnel tests has been developed. Infrared thermography and a knowledge-based system are applied to this technique. The evaluation system developed in this study can be used effectively at an early design stage of a tall building development, e.g., when the cross sections and/or the arrangement of buildings are examined from the view point of the pedestrian-level wind environment.

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This research aims to analysis the flow field and the transportation of contaminants around the respiratory region. In this paper, the flow field around respiratory area of breathing thermal manikin is measured by PIV (Particle Image Velocimetry) system. The experiment is performed in a chamber controlled stagnant state with constant temperature. Respiratory conditions is set three different cases, inhalation and exhalation all the time, and inhalation and exhalation in turn. In result, in the case of inhalation steadily, the thermal manikin inhaled air transported from the lower space of the mouth. And so, in unsteady respiration case, thermal manikin inhaled air from same space with the case inhaled air steadily. This result verified the validity of having performed steady analysis of the flow field around the respiratory area in numerical computation.

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This paper introduces the numerically simulated flow patterns which are formed around bluff bodies with various cross sections. The numerical procedure consists of the modified k-ε model proposed by Kato & Launder and two-layer model. Computations were carried out for rectangular cylinders at rest, at vortex-induced vibration, at torsional vibration and at flutter. When the motion velocity is larger than wind speed, flow patterns are quite different from the one at rest. Aerodynamically, this case corresponds to the vortex induced vibration in which a very strong concentration of the vortices and its convection along the surface of the cross sections are observed.When the motion velocity is smaller than wind speed, Flow patter is rather simple and similar to the one at rest. Although the numerical procedure is simple two-dimensional analysis, the results were compared with wind tunnel experiments and the satisfactory agreement were demonstrated.

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This article reviews advances of pressure-sensitive paint (PSP) technology made in the last decade. Emphasis is placed on technical aspects of PSP including paint formulations, measurement systems, data processing, and aerodynamic applications. From these reviews, the subjects for future work have been identified. These include the development of multi-color paints, lifetime measurement system, higher time-response PSP system, low-speed paint, and applications to hypersonic flow, high Reynolds-number cryogenic flow, and rarefied gas flow (or micro flow). PSP technology is still at a developing stage. Multidisciplinary cooperation between chemists, aerodynamicists and optical engineers is a key to the development of new generation PSP.

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The present paper describes the temperature dependence of the pressure sensitive paints in the pressure range of 1101.3kPa, and the wall temperature range of 263303K. The pressure sensitive paints investigated in the present work are PtOEP, PtTFPP, H₂TFPP, H₂TCPP, H₂TSPP, and H₂TTMAPP, and painted on a commercial porous silica thin-layer chromatography (TLC) plate. We estimate the uncertainty of the measured pressure value due to the change in the wall temperature. As a result, the uncertainty of H₂TFPP is smaller than 3.5kPa per Kelvin in the present measuring range, and this paint is the most useful paint among the PSPs tested in the present work for measuring the surface pressure of the aerodynamic body on which there are temperature distributions.

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A new approach to correct for the temperature effect on Pressure-Sensitive Paint (PSP) is proposed. This method, what we call Non PSP, consists of a PSP film covered with an oxygen-barrier layer. The resulting film acts like temperature-sensitive paint. Two types of barrier polymers, poly-vinyl alcohol and poly acrylic acid, were evaluated in this study. It was found that those barrier layers could cancel the pressure sensitivity of PSP and enhance the temperature sensitivity. To validate the performance of Non PSP for temperature correction of PSP measurement, a supersonic jet impingement test has been performed. Using PSP/Non-PSP combination, pressure and temperature fields on a flat plate induced by a jet could be visualized simultaneously. However, the paint-derived data showed a residual error in pressure, indicating that the factors like hysteresis and humidity had an effect on the response of Non PSP to pressure.

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Binary pressure-sensitive paint (PSP) with a reference phosphor was developed in order to improve the measurement accuracy by removing the influence of a model movement. Blue emitting phosphor ((Ba, Eu) MgA1₁₀O₁₇) and PtTFPP were used as a reference luminophor and pressure-sensitive luminophor, respectively. The emitting intensity of the phosphor, l_phos, is practically independent of the atmospheric pressure and temperature. Furthermore, the emission of the phosphor is spectrally separated from the one of PtTFPP, and these luminophors are not chemically interfered with each other. Therefore, the mixture solution of PtTFPP and the phosphor was compounded as a binary pressure-sensitive paint. To demonstrate the effectiveness of this paint, a surface pressure map for the interaction of a cylinder mounted normal to a flat floor with a supersonic boundary layer were measured. As a result, the erroneous pressure distribution due to the model movement was improved by using the ratios of ratios, i.e. : (I_psp) / (I_phos) / (I_psp/I_phos) _o, where the o refers to the intensity ratio taken under reference condition, although the problem on the quantitative error and the dispersion of the phosphor must be solved.

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The pressure sensitive paint (PSP) has a potential for high-frequency response. To show the feasibility of a PSP measurement system, the Cassegrain type optical probe was used. High-frequency pressure fluctuations at frequencies on the order of kilohertz produced by chopping an underexpanded jet were measured using the Cassegrain optics pressure measurement system. Pressure traces obtained by the present system and their power spectra are compared with those by a conventional pressure transducer. The agreement between those traces is quite good. The results shows that PSP measurement system has the frequency response on the order of kilohertz.

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The objective of the present work is develop the high resolution pointwise pressure-sensitive paint (PSP) measurements system. The Cassegrain optics and diode laser has been used to satisfy this purpose. This measurement system has high spatial and temporal resolution. The present optics can effectively collect the luminescence emitted from the area within 0.1 mm in diameter. The results obtained by the present system have been compared with those by a conventional pressure transducer in time domains, and the agreement between these results is quite good.

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We have developed an ICCDcamera based luminescence lifetime imaging system, it enables the imaging of luminescence lifetime of pressure sensitive paint. This system consists of an illuminator for excitation, an ICCDcamera for imaging, a timing controller and a computer for image acquisition and processing. Basic characteristics of this system and its application to the gated intensity ratio method are described. PSPs measured here are PtOEP and FtTFPP. In the measurement by the gated intensity ratio method, both pulsed excitation light and sine-wave excitation light have been applied. With the single-exponential approximation in image processing, the obtained lifetime value is roughly in agreement with the value measured by conventional lifetime method.

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A new type of pressure-sensitive paint for pressure measurement in a cryogenic wind tunnel is present. This paint is composed of Pyrene-based luminophores adsorbed onto anodized aluminum surface (AA-PSP). Various derivatives of Pyrene were calibrated by changing the mole fraction of oxygen in the 0.1 m Transonic Cryogenic Wind Tunnel (TCWT) at National Aerospace Laboratory (NAL). It has been verified that Pyrene-based AA-PSPs show high oxygen sensitivity in the 02 concentration range from 4 to 1000ppm. These AA-PSPs were applied to a 14%-thick circular arc-bump model and tested in TCWT at 100 Kelvin. Surface pressure distributions on the model were clearly imaged with high spatial resolution and S/N ratio. A comparison of the measured intensity data with the pressure tap measurements has suggested that the in situ calibration can be used to obtain quantitative pressure data.

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Temperature-sensitive paint (TSP) has been applied to boundary-layer transition detection in a cryogenic wind tunnel. Three TSP dyes, Ru (bpy), Ru (trpy) and Ru (VH127), were evaluated for a temperature range from 100 to 298 Kelvin using a LN2-cooled cryostat and a spectrofluorometer. It was found that TSP based on Ru (trpy) has the highest sensitivity among these three. We used epoxy-based sprayable paint as insulating material for a test model. No cracks appeared at cryogenic temperatures as long as the total thickness is kept less than 80 microns. To demonstrate the capability of this TSP/insulating-layer combination, we conducted a 2-D airfoil model test in NAL 0.1-m Cryogenic Transonic Wind Tunnel. Natural and forced transition patterns were successfully visualized using TSP at temperatures from 100 to 150 Kelvin.

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To apply the PSP (Pressure Sensitive Paint) to measurement of pressure distribution on a solid surface settled in the rarefied gas flows, the fundamental features, such as pressure sensitivity and luminescence intensity, are examined for four PSPs; PtOEP/GP197, Bath-Ru/Anodized Aluminum (dipping and electrochemical), PtTFPP/poly (TMSP). The experiments are carried out in the pressure range of 133Pa to 1.0 × 10^-2Pa and the luminescence intensity from the PSP irradiated by Xe-lamp is detected by the ICCD camera. In this study, it is found that PtTFPP/poly (TMSP) is more suitable in this pressure range from a point of view on the luminescence intensity and the pressure sensitivity.

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The mixing fields within a scram-jet combustion chamber are visualized using pressure sensitive paint (PSP) as an oxygen sensor. The experiments are performed in a small supersonic wind tunnel at the National Aerospace laboratory - Kakuda Research Center (NAL-KRC). The main stream mach number is 2.4, and the dynamic pressure ratio between the injected gas and the main flow are 0.3, 0.7, 1.1 and 1.5. Three fuel injection nozzles are used; air and O₂ is injected from these nozzles. The results show that the jet has its own independent flow structure, and that little mixing of gas occurs between the flow structures created by each nozzle.

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The pressure sensitive paint (PSP) has recently received wide attention as a revolutionary new optical pressure measurement scheme. The objective of the present work is to show the feasibility of PSP as a measurement tool of jet impingement flow fields. The results show that the large difference of the wall static temperature leads to nonphysical results. The key points necessary for the reliable measurements is thermal diffusively to keep uniform wall temperature.

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A method for measuring the shear stress distribution over a solid surface in a flow was developed with a use of shear-sensitive liquid crystal coatings and the stereoscopic observation by two color CCD cameras located side by side. This new technique was successfully applied to the shear-stress measurement over the side wall of the cylinder in a uniform flow.

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This paper describes that key idea to introduce wavelets transform, one-.two- and. three-dimensional wavelets transforms are introduced by means of Daubechies 2^nd order base function. Finally, n^th order bi-orthogonal wavelets transform algorism is derived in terms of tensor notation. As a result, it is clarified the mathematical as well as physical meaning of the discrete wavelets transform. Thus, this paper suggests that various signal and image processing problems can be carried out by the discrete wavelets transform.

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A feature extraction method based on Wavelet transform is proposed. The proposed method is compared to Fourier descriptor. The experimental results with a ADEOS (ADvanced Earth Observing Satellite) / AVNIR (Advanced Visible and Near-Infrared Radiometer) image support an effectiveness of the proposed method.

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