Six-degree of freedom motion of a free-running model ship in waves was measured at a model ship basin equipped with a moving carriage by using an optical motion measurement system. The carriage can track a model ship automatically by using another system that measures the horizontal movement of a model ship. Measured optical ship motion data are compared with data obtained by a fiber optical gyro to evaluate the optical data validities. Discussion about applicability of the optical measurement system both to the motion measurement and carriage tracking is provided.

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The aerodynamics of rotary Phoenix tree samaras was experimentally studied. Smoke visualization and pressure measurement were performed using the rotating samara model in a vertical low-speed wind-tunnel. As a result, it was visualialized that the samara made separation vortices at the leading edge. The vatices produce high negative pressure, and contribute the production of thrust equals to the weight. Additionally, the relations between torque distribution and the shape of samara were also discussed.

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Identification of Region Of Interest (ROI) is of great importance for effective visualization of a three dimensional flow field. A primary issue on users' manual specification of ROI is that their knowledge and labor are required. In this paper, a newly developed method that generates streamlines with appropriate density automatically, which is employing identified ROI from eye tracking data. The ROI in 3D space is obtained by projecting the eye fixation to the flow field. Using the measured eye data when the users observe physical quantity relevant to flow such as pressure, the proposed system allows the users to concentrate on their observation without regard to the identification of ROI.

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This report discussed the effect of plaque size and of inlet pulse waveform on flow behavior including shearing stresses at the blood vessel wall. In the present study, we developed simulation software of the carotid artery model with the plaque shape expressed by Gauss probability function. We also compared between simulation results and some clinical data from the power Doppler image. The results showed that the local blood-flow distribution including backflow criterion is strongly influenced by the shape of plaque and by the inlet flow rate.

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In medical area, one of the best devise is a stethoscopy to diagnose dysfunction of heart, lung, and bowel. However, the diagnosis technique is strongly depending on the auditory ability of physician as well as their age, thus this technique has not an objective standard. We proposed a new identification technique of heart sound based on the pattern obtained by two types of signal analysis to assist stethoscopic diagnosis. The technique consists of both fast Fourier transform (FFT) and Wavelet signal analysis. We examined 26-cardiac example prepared in the textbook for training young physician. The results showed clearly the differences to identify heart dysfunction as objective diagnostic pattern for both the physician and the patient. We can expect the a new system based on the sound-pattern identification and diagnosis.

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In recent years, elderly people who require long nursing care are increasing with aging of society. So, clinicians as well as scientists and family doctors have developed an increasing interest in osteoporosis, which is defined as the clinical manifestation of the atrophy of bone. Thus it is essential to establish fracture risk evaluation method based on biomechanics. The purpose of this study is to establish a new three dimensional visualization method for creating image of micro-structure of human in vivo calcaneus (almost spongy structure) using ultrasound A-mode signals. The method is based on distinction between bone and bone marrow by A-mode signal processing using the modified curve (Eq. 2). We have also developed a prototype system and demonstrated to examine the effectiveness of the method by creating the human calcanues 3-D imaging.

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Until recently, keyboard has been used as the primary input method for machinery operation system. But in recent years, numerous methods related to direct input interface have been developed. One of them is to measure the surface electric potential that generates on the skin surface during muscle contraction. Based on this fact, hand finger operation can also be recognized with the help of the surface muscle electric potential. This report mainly explains the method of recognizing the crookedness states of the hand fingers from surface electromyogram (SEMG) signals.
Moreover, the research on the biosignal control system with eye movement is also reported. We have designed a new biosignal control system that offers the disable the opportunity to control some electrical appliances. The biosignal control system is based on the signals derived from the forehead during eye movement, using five electrodes fixed on the forehead. The four directions of eye movement (up, down, left, and right) allow as four primary control signals. With selection of 2 signals from the four primary signals, we can get 16 different signals.

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The pressure sore is a trouble by the mechanical loading. As for this, the stress concentration occurs to the skin surface, and, next, sphacelism is meant by the skin. It is the present conditions that there is not correct evaluation method so that it is anisotropy composite material as for the biotissue such as the skin, and behaving becomes complicated transformation by the external force.
Therefore, by this report, we use a strain gauge for the skin of the decubitus (bedsore) pocket penumbra and report it about the result that tried the distortion distribution measurement.

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Recently, technology to handle a molecule of nano scale advances, and an applied technology is developed in every area. Development of nano-DDS is perfomed worldwide in the med-tech area. We try the effectiveness of nano-DDS. The dynamic behavior of nano-scale magnet in biomaterials is not well known. Therefore it is necessary we perfome direct observation, and to get information of the behavior. Using strong photon beams in Spring-8 facility, we trace the magnets and investigate the leaf or the egg.

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To reduce aerodynamic sound, investigation of the sound generation mechanism in flow field is very important. The detailed investigation of the sound source requires velocity measurements with high temporal and spatial resolution and the development of sound source exploration. In this study, sound source in the turbulent mixing layer have been investigated by the time-resolved stereoscopic particle image velocimetry (TRSPIV). Powell's sound source and Reynolds stress component of the Lighthill's sound source have been evaluated from the experimental results and compared with those obtained from direct numerical simulation.

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Thermocapillary (or Marangoni) convection in a cylindrical liquid bridge and its transition to oscillatory and chaotic states has been stimulating strong interest among fluid dynamicist in the microgravity community. To clarify the mechanism of such a phenomenon, microgravity experiment will be carried out in the International Space Station (ISS) and several parameters (Dynamic Surface Deformation (DSD), temperature, mode structure, etc.) of liquid bridge will be measured. But g-jitter in ISS might have harmful influences on the measurement and thermocapillary flow. So, in this experiment, g-jitter is reproduced on the ground by using piezo-electric actuator (PZA) and feedback control system and DSD and flow pattern are observed. As the result, influence of g-jitter is removed by image processing and signal filter, and it is clarified that g-jitter has little effect on the mode structure. In addition, resonant frequencies of liquid bridge are observed and it has little probability that g-jitter causes sympathetic vibration of liquid bridge.

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Mixing T-junctions are encountered in many industrial applications. This study has been conducted to clarify how two fluids with different characteristics are mixed turbulently in a cross-flow type. T-junction. The velocity field in the channel is investigated by PIV, and visualization is conducted to see the behavior of the interface between two flows in the mixing section by oil smoke. We extracted the dominant structures of the velocity field and concentration field by POD analysis. It is clarified that the interface of two flows is oscillating vertically and mushroom-like eddies are superposed on it. We have concluded that the vertical oscillation of the interface is caused by the fluctuation of the streamwise velocity component, and the mushroom-like eddies are caused by the vertical fluctuating velocity; the former produces the streamwise turbulent heat flux, and the latter produces the vertical one.

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Simultaneous CH double-pulsed planar laser induced fluorescence (DPPLIF), OH PLIF and stereoscopic PIV measurement has been developed to investigate dynamics of flame elements in turbulent premixed flames. The measurement was conducted in relatively high Reynolds number turbulent jet premixed flames. By comparing the flame displacement speed with fluid velocity near the flame front, local pseudo-burning velocity is evaluated. The most expected local pseudo-burning velocity is about 0.4 m/s, which is good agreement with laminar burning velocity.

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A micro flow meter for measuring small liquid flow rate is fabricated by using 3-D microstereolithography. The flow meter consists of an impeller, 500μm in radius, and a casing. The micro system is installed in a PDMS square channel, 500μm in width, through which the liquid to be measured flows. The flow rate is measured by counting the rate of rotations of the impeller. The flow characteristics are studied by visualization and measurement based on PIV technique. It is shown that there is a good linearity between the flow rate and the rate of rotations counted in the range of 5000-25000μL/min. The dynamic response of the present flow meter is evaluated to be about 0.25s, which is short enough to make measurement of unsteady flows. Time-averaged velocity distribution inside the micro flow meter is obtained.

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We proposed an x-y movable cavity block in which 21 optical fiber sensors or 4 pressure sensors were installed in order to detect the melt passing timing at each fiber sensor edge or to measure the pressure profiles. The cavity flow pattern and the pressure distribution were measured by this mold in the partial thin-wall cavity with thin-wall area of 0.05mm in thickness. By shifting the location of the cavity block step by step in the x and y directions, we could successfully measure
the whole cavity filling patterns and cavity pressure distributions in partial thin-wall cavity by overlapping all the detected data in a cavity area under ultra high-speed injection conditions up to 2000mm/s in screw speed.

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In the melting of high-polymer material on industrial applications, unsteady flow phenomena occurs on its non-Newtonian properties. The unsteady interface phenomena in melt-front of high-polymer materials (PP) with several flow configurations (rectangular flow with 5mm & 1mm thickness, with/without patterned and artificial surface control) are assessed as local and unsteady geographic shape of the gas-liquid interface experimentally using images taken by high-speed CCD. From experiment results and considerations with wavelet analysis, the gas-liquid interface time-dependently changes its shape and fluctuating properties. Two-way phenomenal transition and all-over instability are also detected in the system, which that one is from the center to wall (fountain-flow-like), another is from near-wall to center by non-uniform slipping phenomena at near-wall region. These results under such experimental conditions have the different
properties quantitatively, but not making clear yet. Moreover based on our findings, special thin film layer with functional effects has been tried with a artificial-layer on plate, particles-layer and melting mist flow.

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This paper deals with a high viscous fluid behavior under the coating head of Melt Transcription Molding Process, which is one of a novel polymer processing recently developed. Flow field analysis of the process is the key issue to determine the optimum process conditions. Thus a simplified experimental apparatus was constructed to model the coating process under iso-thermal condition, and the particle image velocimetry (PIV) was applied to visualize the flow field. The results showed that the flow condition was significantly influenced by the feed rate of the high viscous fluid and the geometry of the die exit. Pressure distribution on the coated surface was also estimated according to the strain rate in the field. Obtained result was compared with the pressure profile experimentally measured, and they showed quantitative agreement. By summarizing these results, optimum conditions to stabilize the coating flow was discussed.

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A specific ultra-high speed video camera capable of shooting one million frames per second in full frame, enables the visualization of injection molding phenomena by combining the glass-inserted mold with an optical system which can magnify by more than 130 times from outside the mold at even higher accuracies. In this study, we attempted for the first time to directly visualize unique gate flow behaviors at the ultra-high-speed injection conditions, not only in the case of the molding with LCP using an obstacle-pin cavity but also in the case of the jetting and bounding phenomena of the injected PS melts just after the submarine gate.

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Planar laser induced fluorescence (PLIF) of OH radical was conducted to clarify the relation between the flame structure and noise characteristics of the swirl-stabilized combustor controlled by secondary fuel injection. Three dimensional (3D) flame structures of turbulent premixed flames were reconstructed from the PLIF results on multiple planes. The 3D structures reveal that secondary fuel injection reduces the fluctuation of high temperature gas in the recirculation zone and that of flame front in the flame zone, which results in the reduction of the sound source.

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Although the spark tracing method is known as one of the most classical techniques of flow visualization, the measurement by this technique has been limited to a qualitative observation or to one-dimensional velocity measurement. Recently, the authors of this study have been succeeded in measuring the two- or three-dimensional velocity field by applying the DP (dynamic programming) matching technique, which has commonly been used in the voice recognition, to the images obtained by the spark tracing method with the aid of one or two high speed cameras. Presently, the distributions of the mean velocities, rms velocity fluctuations and the Reynolds stresses in an axisymmetric free jet have been compared with those of the previous study. In order to increase the accuracy of this technique, the powder of aluminum oxide, which shows the radiant trails while they are burned by sparks, has been introduced to the flow.

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The phenomena of the turbulent coherent structures and collapse of vortex are indispensable to realize high performance in heat transfer with a small pressure loss. Not only time-mean thermo- and fluid- dynamics but also unsteady and sequential 3D-phenomena are very important to study and control these phenomena in engineering applications. The most percentage of heat transfer enhancement were given birth for very short time period, when the turbulent structure just come and make effect on the heat transfer field near wall. But the time-dependent correlations between unsteady fluid and heat transfer fields are still unknown, which are most interesting and exciting to investigate experimentally. In this study, the three-dimensional velocity measurement system would be improved with multi-color field by the illumination optics for liquid crystal projectors and image processing for the detection of 3-D velocity vector. The unsteady collapse processes of periodic vortex by plate are investigated near wall region on the plane, and are shown by graphic figures. The results also are shown about the effects of unsteady velocity field with the adding the micro-bubbles near wall for control.

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Hall thruster is an electric propulsion device in which high thrust efficiency is achieved in the middle specific impulse. In previous works based on experiments and numerical analyses, the dependency of the 20 kHz-range discharge current oscillation amplitude on anode orifice configuration has been analyzed. Using the results of neutral direct-simulations, the influence of the neutral distribution on the amplitude has been investigated. In the present work, for the purpose of more detail investigation of the influence of the neutral distribution, the ionization and acceleration process in the acceleration channel for various orifice diameters were analyzed using a hybrid-PIC code. The results of visualizations of the ionization rate distribution, which influences the oscillation amplitude, show that the smaller orifice causes the ionization concentration.

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Unsteady three-dimensional detonations in both a circular tube and a square tube are simulated in order to reveal three-dimensional shock structure. The modes in the square tube are the rectangular mode in phase, the rectangular partially out of phase, and the diagonal mode. The rectangular mode partially out of phase is a spinning mode. Those in the circular tube are the spinning mode and the two-headed mode. Three-dimensional visualization for these modes is able to understand unsteady, complicated, and interesting shock wave patterns.

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A study to establish a numerical prediction method for vibro-acoustics during rocket launch has been conducted. This method consists of some analysis elements: numerical analysis of sound generation, propagation, transmission, and vibro-acoustics of payload. In this paper, sound pressure distributions obtained by these analyses are visualized. At first, flow and acoustic fields of modeled H-IIA launch pad are shown, which is obtained by a hybrid methodology of the Euler and Linearized Euler Equations (LEE) solvers. Then, an arch-shaped transmission wave is observed from a sound transmission analysis of hollow wall model using the Finite Difference Time Domain (FDTD) method. Finally, it is clearly shown that the acoustic field is affected by structural vibrations and the coupled vibro-acoustic problem of flexible satellite model can be solved by the Wave Based Method (WBM).

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In Japan, a 5-year R&D project has been in progress toward the development of an environment friendly high performance regional jet aircraft under auspice from New Energy Development Organization of Japan (NEDO) since 2003. In the project, the research of airframe noise has been conducted for achieving lower commercial noise.
At first experiments were conducted on 20%-scale half span model in the JAXA Wind Tunnel from 2005 to 2006. In the test, the array microphone has been used to visualize the airframe sound source and it was found that the slat noise is the one of the biggest sound source for the aircraft approach condition. Then the generation mechanism of the slat noise has been calculated by using CFD for developing the device that was able to reduce the slat noise.

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A 5-year R&D project has been in progress in Japan toward the development of an environmentally friendly high performance small jet aircraft since 2003. Authors have been trying to apply a MDO tool to the aircraft design. In this MDO tool, SOM was adopted to extract the essential design knowledge from the optimization results. This paper presents the example of the application of the SOM to an engine-airframe integration design.

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Flow visualization using a color schlieren system and wall pressure measurements have been performed to elucidate the interaction of a weak normal shock wave and a boundary layer in a constant-area duct. The freestream Mach number just upstream of the shock is about 1.3 and the flow confinement given as the ratio of the boundary layer thickness to the duct half height ranges from 0 to about 6%. The schlieren visualization shows that with increasing flow confinement, single normal shock gradually changes into a shock train consisted of four shocks.

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For a surface pressure measurement in wind tunnel, following techniques are used: a differential pressure meter, and the pressure-sensitive paint method. The former one can measure the pressure with high-precision, but the measurement cost is expensive. The latter one can reduce the cost; however, the change in the oxygen-partial-pressure becomes small at low-speed. In the author's previous study, a new pressure measurement method has been proposed. The method uses a laser displacement sensor. The surface pressures are obtained by measuring the deflection of a film which is attached on the surface of the model. The verification experiment using a high precision sensor, whose reference length from the sensor head to the target is 30mm, demonstrates reasonable results. In this paper, a middle precision sensor, whose reference length is 150mm, is also introduced. The measurement accuracy of the pressure measured by two different sensors is demonstrated.

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A volumetric ignition mechanism induced by burned gas jet injection into lean hydrogen-air mixture was observed. A planar LIPF measurement of OH radicals and high-speed video camera record were used for revealing the novel ignition mechanism. The ignition occurs in the activated hot gas mixture generated via the turbulent mixing. The multi-spot ignitions occur simultaneously in the whole activated volume.

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In connection with the hazard evaluation of hydrogen stations for fuel-cell vehicles, an image velocimetry using brightness subtraction method was applied to accurate time-dependent measurement of hydrogen-air flames in open space. An image filtering technique of enhancing the flame front edge was introduced with a spatial difference scheme for obtaining local flame velocities. The processed flame fronts were not clearly identified. The reason is attributed to the performance of the CMOS device and the A/D converter of the high-speed video camera employed.

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A vertical take-off and vertical landing rocket is one of the future space transportation vehicle expected as fully reusable system. In the landing phase of vertical lander, the vehicle is decelerated by the main engine thrust and lands softly to the ground site. Then its aerodynamic characteristics are affected by the interaction between the engine plume and the subsonic free-stream against the vehicle. In order to investigate the influence of such interaction, wind tunnel tests were conducted. The aerodynamic forces and surface pressure were measured by using scale model of the Reusable Vehicle Testing (RVT) which is a small vehicle built for flight tests in ISAS/JAXA. Flowfield around the vehicle model was visualized by using Particle Image Velocimetry (PIV) method. As a result, the drag force and pitching moment acting the vehicle were affected by the change of pressure distribution due to the jet/free-stream interaction.

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An LIF imaging spectroscopy was applied to the quantitative measurements of NO concentration and temperature profiles in a jet fuel flame. The NO mole fractions were determined comparing the LIF signals of NO-seeded flame and non-seeded flame. A two-line thermometry technique was used for obtaining the temperature distributions. A narrow-band pass filter was used to sufficiently remove noise lights, and two-dimensional distributions of concentration and temperature of NO were obtained. The flame was stabilized inserting a honeycomb ceramic tube on the burner exit of preheated kerosene-air mixture. The result shows that NO is produced via the thermal NO mechanisms and that the NO concentration and temperature were higher in comparison with a methane-air premixed flame in a standard Bunsen burner.

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Aerospike nozzles have been expected as thrust nozzles for SSTO vehicles, because they show high performance in wide range of altitude or pressure ratio. Sidewalls for linear aerospike nozzles are indispensable to prevent the undesirable spanwise expansion of jets, which reduces the thrust. However, oversized sidewalls increase the weight of nozzles, and it is important to optimize the shape and the size of sidewalls. In this study, the flow field structures around the linear aerospike nozzles are visualized by using the laser induced fluorescence (LIF) technique and the pressure distributions on the nozzle spike are analized by the pressure sensitive paint (PSP) technique. The optimized shape of sidewalls is suggested by comparing the pressure distributions on the nozzle spike with three types of sidewalls and that without sidewalls.

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Recently, the Multi-level Partition of Unity (MPU) method has been used as a technique to create an implicit surface from a large number of points. In this study, we propose multi-resolution representation of the implicit surface based on the MPU method. If the concept of the multi-resolution representation is incorporated into the MPU method, the implicit surfaces become tunable in various situations. Furthermore, the evaluation time of the implicit function can also be shortened. In proposed approach, we create and save the small domains and the local quadratic functions recursively until the given limit precision. For the case with the evaluation of the implicit function, we select quadratic functions satisfying the given precision that should be more moderate than the limit precision. As the result, the implicit surface of arbitrary resolution can be generated quickly.

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Volume visualization is widely used in medical, scientific, and other fields. Since volume data are generally large, data compression techniques become important. In addition, volume data are usually discrete, and must be interpolated to execute volume-visualization algorithms. For high-quality visualization, higher-order smooth interpolation is required. But it is difficult to make such interpolation compatible with the data compression. Recently, the MPU (multi-level partition of unity) method has been developed to reconstruct a smooth implicit surface from a large number of 3D points. Our purpose is to construct a new version of the MPU method that is applicable to interpolate discrete volume data, generating a highly-smooth scalar field described with small-size data. It is demonstrated that the data size is reduced drastically, keeping the smooth feature of the interpolated scalar field.

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Supersonic jets from a high-velocity oxy-fuel thermal spraying gun have been simulated and visualized by numerical analysis. The thermal spraying gun in the present simulation has the same shape as that of a commercially used gun. To visualize the jet structure, the equi-Mach number contours of supersonic jets have been depicted, and the Mach number and static pressure distributions along the jet axis have been, calculated both for under-expanded and correctly-expanded supersonic jets. For under-expanded jets, the "diamond shock" pattern has been observed.

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In this paper, the correlation between the amount of dampening water on an offset printing plate and the intensity of speckle patterns generated on the plate is examined by experiment and numerical simulation. In experiment, speckle pattern observation is performed for two different conditions that the plate is at rest and dynamically move attached to a rotating cylinder to evaluate the feasibility of speckle intensity method in offset printing system. In numerical simulation, time variation of speckle intensity is simulated with the model of the distribution of dampening water on an offset printing plate, considering the reflection factors on water surface and the printing plate. From the results, it is seen that the speckle intensity method has usability on dynamic condition and speckle intensity depends on observation angle.

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This paper describes a detection method of two types of exfoliations for outward tile wall. One of the tile exfoliations is an outer exfoliation separated the tile surface from mortar concrete, the other is an inner exfoliation deteriorated space between the substrate and mortar concrete. In order to research these exfoliations, we focused attention on the wavelet analysis that enable to analyze the frequency element of a waveform on time phase continuously. In part 2 of this study, comprising the conventional detection methods in which the inspection robot was applied and new method used by wavelet analysis, the characteristics of these methods were verified respectively. As a result, it found that the peak rate method detected outer exfoliation, the cross correlation method detected inner exfoliation and that the wavelet method detected this exfoliation instantly. A best effective detection flowchart inspected the tile exfoliations to apply to the inspection robot was proposed.

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The factors causing errors in inverse analysis of the velocity and pressure fields in a moving boundary flow from the time-dependent configuration of the boundary are investigated.

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Abstract In many cloth simulation methods about 3DCG animation, cloths are modeled by finite material particles. The author propose a method to derive equation which describes time evolution of the deformation of cloths, based on the continuum surface model. This equation is generalized to an abstract time evolution equation which describes the deformation of general surfaces in high dimensional Euclidean spaces.

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