The aim of the present study is to investigate the nonequilibrium condensation of alternative Freon vapor on the cold wall behind the shock waves. To clarify the relation between the shock wave propagation and the phase change of vapor behind the shock wave on the shock tube side wall, the liquid film thickness and heat flux are measured. Experiments were carried out by using a diaphragmless and a low temperature shock tube that can be cooled down to 100K by using liquid nitrogen. The time dependent thickness of liquid film was measured by an optical interferometric method based on multiple reflections of a He-Ne laser beam at the interface of the thin liquid film and the transparent optical glass. The condensation heat flux was measured by a platinum thermo-sensor. It is found that the liquid film thickness and the condensation heat flux rapidly change behind the reflected shock waves. It is also found that for the same initial temperature, a higher p₂ led to a faster growth of the liquid film, however it is not cleared the difference in the liquid film growth behind the reflected shock wave.

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Biomass-based plastics are considered to be one of the most important derivatives of biomass. By using the softening and self-adhesive properties of woody biomass, several studies have been conducted on molding methods for thermo-fluid wood. Little is known about the flow characteristics of thermo-fluid wood. In this study, experiments on hot extrusion in capillaries are conducted to clarify the viscous property of thermo-fluid wood powder. The following results are obtained. As the temperature and water content decrease, it becomes harder for the biomass sample to become soft, and thus the hot extrusion cannot be performed. From the relationship between wall shear stress and wall shear rate, it is found that the power index of wall shear rate is below unity, and therefore the thermo-fluid wood powder behaves as a nonNewtonian pseudo-plastic fluid. The experimental correlation of the apparent viscosity of thermo-fluid wood powder is proposed, and the apparent viscosity can be estimated by using the present correlation with an accuracy of ±50 %.

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A velocity slip between the gas and the liquid phases due to the density difference lowers the conversion efficiency of the nozzle. On the other hand, the velocity slip between micro-bubbles and the liquid around it is generally small. In the study, the pressurized dissolution method and its modified method were used to generate micro-bubbles. In the modified pressurized dissolution method, an orifice plate was located before the nozzle to make micro-bubbles and it was found that the flow was supersonic in the diverging part of the nozzle. Furthermore, the effect of the amount of the dissolved gas on the flow was studied. The void fraction of the flow was increased as the amount of the dissolved gas but the volume of a single bubble at the throat did not change. The calculation of sound speed was carried out to compare with the throat velocity for determination of the flow condition.

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The purpose of this study is to experimentally investigate the flow structure of liquid film flowing down an inclined wall using photochromic dye marking method. The dye trace was marked by UV laser (λ= 355nm) and its behavior was recorded by a CCD camera to obtain the liquid film surface velocity. The diameter change of the dye trace was measured with the velocity. The velocity was then compared to the diameter change of the dye trace to clarify the flow structure during the presence of wave. As a result, the liquid film surface velocity was found to decrease in the wave front and rapidly increase in the wave back.

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We developed a new wave power generation system installed in a slit type breakwater. This system has great advantages of no requirement of sea surface affecting on shipping route or fishing ground. In this system, accelerated flow from the slit of the breakwater drives waterwheels. In this study, the output power of the waterwheels was measured using a 1/12 reduced scale model to examine the optimal condition of type, diameter and mounting configuration of the waterwheels. Scaling law for estimating real scale output power from the reduced scale experiment was also examined by numerical simulation. A single mounted crossflow waterwheel achieved the maximum output power when its diameter is 1.5 times the width of the slit. Output power was predicted to be proportional to 3.5th power of scale and the square of wave height.

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In order to develop the non-contact scraped surface heat exchanger with the non-contact scraper blades,experiments were performed for cooling corn syrup water solution as a test process fluid flowing in a typical scraped surface heat exchanger with a constant clearance between the scraper blade and the heat transfer surface. The local heat transfer coefficient and the power consumption were measured by varying the flow rate and the viscosity of test process fluid, and the rotational speed of scraper blades for the some constant non-contact clearances in the different scraped angles.Based on these experimental data, the effects of the non-contact clearance and the scraped angle on Nusselt number and Power number were examined in comparison with these correlations for the perfect contact scraped surface heat exchanger with the blades pressed to the heat transfer surface by springs. As a result, it was clarified that Nusselt number and Power number in case of the noncontact clearance 0.2 mm had decreased from those in the perfect contact scraped surface heat exchanger by 0 - 30 % with an increase in rotational Reynolds number and by60 % on the whole, respectively.

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To improve the performance of absorption refrigerators, a correct understanding of the heat transfer characteristics of an aqueous lithium bromide solution is necessary. In the present study, experiments were carried out to obtain reliable data on the pool boiling heat transfer characteristics of an aqueous lithium bromide solution (54.8 wt%). From the measured data, the following new results were obtained. The boiling heat transfer of an aqueous lithium bromide solution improves with increasing pressure. The superheat of boiling inception increases with decreasing pressure. The boiling inception superheat results agree with Gibbs's theory, and the surface tension is found to have a strong effect on the boiling inception superheat. The transition heat flux for the transition between intermittent and nucleate boiling is negligibly affected by pressure. The heat flux is 200 kW/m² for an aqueous lithium bromide solution and 350 kW/m² for water. The nucleate boiling heat transfer coefficient of an aqueous lithium bromide solution increases with increasing pressure and heat flux. The heat transfer coefficient can be accurately estimated by the Kutateladze correlation. The Nishikawa–Fujita correlation is not in good agreement with the present data, and a modified Nishikawa–Fujita correlation with improved accuracy is proposed.

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In tensile test of steel specimens, there are several stages in stress-strain relation and strain distribution on the specimen surface is not uniform during the test. In this study, the author investigated measurement of strain distribution in steel specimens during tensile test using digital image correlation method. Plate specimens were used and images of specimen surface were taken continuously as a movie with a digital camera. Static images were taken from the movie file and displacement distribution was measured from the initial surface image before loading. It was possible to measure strain distribution on specimen surface from elastic deformation stage to the final local deformation stage for the whole tensile test. Change in plastic strain distribution during yielding stage was observed. And from the measured results, stress-strain relation was derived from uniform plastic deformation stage after yielding to the final local deformation stage just before fracture.

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The real-time displacement measuring system with digital image correlation method was developed and the displacements of three road-bridges and a railway-bridge were measured under traffic loaded state. The 2D movement of 32x32 partial image could be traced with better than 0.1-pixel resolution by the digital image correlation method.

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We propose an optical control method of positions and orientations of nano/micro objects. They can be utilized to align functional components for novel minute devices in engineering experiments. For this aim, an optical handling method based on an electric field gradient force arisen between metallic antenna arrays by the localized surface plasmon polariton (LSPP) is investigated. The optimum antenna structures were numerically designed to control the positions and the orientations of objects around the local gap of the structures. A part of the concept was verified with actually fabricated silver antenna structures and 2D objects positioning experiments for sub-μm objects under loosely focused trapping beam.

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Bending of a less ductile aluminum alloy A6061-T6 is conducted to investigate the effect of initial surface flaw on fracture. A prediction of surface cracking by means of Oyane's criterion, which is based on void growth and under triaxial stress state, is attempted. The initiation and growth of crack is strongly affected by the location and the depth of the initial surface flaw. The cracking deflection predicted by Oyane's criterion is much smaller than the experimental observation.

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In order to improve the performance in ultrasonic inspections, it is necessary to use an ultrasonic probe with a broad-band and high sensitivity characteristics. Pulse compression techniques using an M-sequence (Maximal length sequence) or a linear frequency modulation (LFM) wave have been reported as a method improving the signal to noise ratio (SNR) and resolution in an ultrasonic testing. However, in order to generate such modulation waves, special apparatuses like an arbitrary waveform generator etc. are needed. In this study, it aimed to develop a novel ultrasonic probe which can generate an M-sequence wave by only a general pulser without such special devices. As a basic study, M-sequence pulse compression (MPC) ultrasonic transducers of 3 bits length and 7 bits length were tried to fabricate using piezoelectric polymer films with a broad-band frequency characteristic. The performance of these transducers has been evaluated by one-dimensional point spread function (1D PSF) in underwater experiments compared with a commercial ultrasonic composite probe. As a result, it was demonstrated that the MPC ultrasonic transducers have the almost same effect as a general pulse compression method and its performance would be improved depending on the bit length of M-sequence.

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Compact and conventional strain distribution measurement equipment is required to monitor the health and the life- lengthening characteristics of infrastructures, such as steel bridges. Digital holography is a convenient method that can be used to measure the displacement and the strain distributions on the surface of an object. Compact and handheld equipment is required for practical use on a field site. Simplification of the optical setup is required to produce more compact equipment. An imaging head with multiple imaging devices was developed by the authors to produce more compact equipment. In this paper, a prototype of a handheld displacement distribution measurement system using eight imaging devices was developed. The evaluation of the displacement measurement using the prototype was shown.

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Flexible electronic and photonic devices are important for future application of flexible displays and general lighting, such as, organic and polymeric light emitting devices and solar cells. Polyethylene terephthalate (PET) films are generally used as substrate for giving flexibility to device. But these substrate are birefringent in nature which will make the problem in the displays fabricated on them. In this paper we report the measurement of the birefringence by using interferometry and Hilbert transform fringe analysis technique. Increase in the refractive index was observed with increasing external bending applied to PET substrate for dual wavelengths, i.e., green and red lasers.

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Accurate 3-D shape measurement systems that use contactless methods are required for appearance inspection of electronic parts in the industrial fields. A fringe projection method using Talbot effect is an effective method to produce the small fringe pitch with a large incident angle. In this paper, a cross-sectional distribution of Talbot fringe patterns in a plane composed of the horizontal axis and the optical axis was visualized. The position and the orientation of the available area can be determined easily with the developed visualizing system. The effectiveness was confirmed with an experiment on a shape measurement using the Talbot fringe patterns generated with an SLD (super luminescent diode) light source.

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The mechanical properties are very important parameter to determine and analysis of stress and strain of a material. In this paper, a time-averaged digital speckle pattern interferometric technique is used to characterize the material constants (Poisson's ratio, Young's modulus and Shear modulus) of the polypropylene (PP) material. Poisson's ratio based on plate bending and Young's modulus based on plate vibration of material are measured by time-averaged digital speckle pattern interferometry with the advantages of non- destructive, non-contact and real-time measurement technique.

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Prosthetic sockets serve as the interface between people with amputations and their prostheses and it is considered an element of major importance in the makeup of prosthesis. The effect of stress relaxation is evident in the material that makes the prosthetic socket. The effecting causes deformation and sagging in the socket due to the lowering in the mechanical properties. This study evaluated the effect of stress relaxation on the socket material by testing this material at 50 °C by creep test and evaluating creep data by using Burger model to obtain the equation of the stress relaxation modulus with time. The results show that the stress relaxation modulus is decreasing with time this means that the material lose their strength with time.

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The copper distribution ratio between the Na₂S flux and silver, L_Cu(flux-Ag) (= [mass% Cu]_{(in flux)} / [mass% Cu]_{(in Ag)}), was measured at 1473 K, and the absorption of copper and silver in Na₂S flux has been quantified. The possibility of the sulfurizative removal of copper in iron through silver phase into Na₂S flux is examined. By combining the L_Cu(flux-Ag) value with the distribution ratio of copper between the silver and the carbon-saturated iron, L_Cu(Ag-Fe), the distribution ratio of copper between the Na₂S flux and carbon-saturated iron, L_Cu(flux-Fe), is derived to be 330 at 1473 K. Therefore, it is expected that the copper in iron can be removed effectively by the sulfurizative removal of copper in iron through silver phase. The copper distribution ratio between the Na₂S flux and silver, L_Cu(flux-Ag) (= [mass% Cu]_{(in flux)} / [mass% Cu]_{(in Ag)}), was measured at 1473 K, and the absorption of copper and silver in Na₂S flux has been quantified. The possibility of the sulfurizative removal of copper in iron through silver phase into Na₂S flux is examined. By combining the L_Cu(flux-Ag) value with the distribution ratio of copper between the silver and the carbon-saturated iron, L_Cu(Ag-Fe), the distribution ratio of copper between the Na₂S flux and carbon-saturated iron, L_Cu(flux-Fe), is derived to be 330 at 1473 K. Therefore, it is expected that the copper in iron can be removed effectively by the sulfurizative removal of copper in iron through silver phase.

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Mechanical properties of natural bamboo fiber (Madake; Phyllostachys bambusoides) and fracture behavior of green composite based on bamboo fiber and biodegradable resin have been investigated in terms of the effects of chemical treatment of the fiber. Fiber fragmentation behavior in a single bamboo fiber reinforced biodegradable resin matrix composite was confirmed experimentally and further analytically. The weak alkali (1.6wt% concentration) treated bamboo fiber showed 6% drop of tensile strength and 13.5 % and 7 % increase of fracture strain and elastic modulus. The results of fiber fragmentation tests were considered with the statistical approaches on composite materials. When the resin matrix is embedded into the slits between fiber cells in alkali treated bamboo, the composite interfacial shear stress, τ is enhanced because of an anchor mechanism. However, it is shown that the brittle fracture mode of composite is caused to the higher interfacial shear stress,τ.

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Skin laceration accidents were simulated by penetration tests using several blades with different tip curvature radius and a skin simulant. Deformation behavior of the skin simulant during the test was recorded, and two-dimensional strain distribution on the surface of the skin simulant was then analyzed using isoparametric finite element method. High strain was observed to be distributed in the area close to the blade penetration area where significant deformation can be recognized.

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The jumping movements of the water springtail were analyzed using the high-speed video camera system. First, details of jumping on the solid flat plate were studied. The maximum jump height was 44 times of the springtail body length. Second, details of jumping on the water surface were studied. Third, details of jumping from the bubble inside into the air were studied. It was found that they can jump from the water surface and from the inside of air bubble. In addition, microscopic observations of jumping organ of the water springtail were conducted with the 3D laser scanning microscope. The unique leaping organ has the hollow cavity with crack. The concavo-convex shape of ventral groove in the abdominal segment of the springtail and the concavo-convex shape of leaping organ fit each other. Jumping characteristics and performance of the water springtail were considered.

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This paper proposes an optimization method of a Japanese keypad location in a smartphone to improve its usability for flick input. This design is based on (i) electromyogram (EMG) measurements in flicking keys on a full-size keypad, (ii) a calculation of percent maximum voluntary contraction (%MVC) from the EMG data and its approximation with a response surface, and (iii) formulation of an optimum keypad location problem and its solution by an optimization technique. This paper demonstrates an application and ascertains the validity of the proposed method by a usability test based on comfort, accuracy, and speed.

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