In this paper, we will try to obtain a force exerted on dislocation, represented by Peach-Koehler equation, using finite element dislocation model. This model is a useful method to analyze dislocation problems with complicated boundary conditions and configurations, proposed before by one of the authors. The force can be obtained by a concept that a reduction of potential energy of external force equals to a work exerted on dislocation, firstly proposed by Peach and Koehler. We also try to obtain the force by same concept in numerical analysis.

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We numerically analyze slip deformation in a model of dual phase materials that contains a spherical inclusion, and show the image of dislocation structure from the numerical results. The result show that four kinds of dislocation structure are formed in the vicinity of the inclusion ; the first correspond to the Orowan loops, the second should be related to the kink wall, and the remaining two are additional structure. Then, we study the reason why these additional structures are formed.

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In this paper, FEM analysises of microelectronics solder joints subjected to cyclic thermal deformation were conducted. Pb free solder alloys (Sn-3.5Ag-0.75Cu) were chosen for the analysis, because of the regulation of using Pb/Sn solder alloys in near future. Results of Pb free solder alloys were compared with that of Pb/Sn solder alloys. Elasto-plastic, elasto-creep, and elasto-plastic-creep analysis were employed in this paper. As a result, it was found that the equivalent stress of Sn-3.5Ag-0.75Cu is much larger than that of Pb/Sn solder alloys, and that the elasto-plastic-creep analysis takes advantage of the simulation both of Pb free and Pb/Sn solder alloys.

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A new multi-objective design approach is proposed for handling many different buckling patterns in the design problem of laminated composite plates. First, a number of various buckling eigenvalues are calculated for some discretized fiber angles of the plate by the Ritz method. These eigenvalues are taken to be the object functions. The second step is based on statistical treatment of the data. For each object function, the calculated eigenvalues for different fiber angles are normalized by the maximum value and then the deviated values are determined on the assumption that the eigenvalues are subjected to the Gaussian distribution with the standard deviation of 10 and the average of 50. The optimal fiber angle θ opt, within the discretized values of fiber angles, is determined by examining the sum of the deviated values of all the object functions.

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This paper deals with effects of the guiding conditions on longitudinal bow of rolled sections at the light reduction rolling. A series of experiments are conducted on a specially designed test mill by varying the rolling and guiding parameters, such as inlet angle, thickness reduction, caliber gap and caliber angle. The resulting curvatures of the rolled sections are measured to discuss the effects of parameters.

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Elastic stress distribution in two dimensional polycrystal models which include about six hundred grains are analysed by finite element method. The results show that elastic stress filed form long range structure whose size sometimes measures up to ten to twenty crystal grains. We discuss the reason for the generation of such long range structure from the view point of young's modulus of each crystal grain and stress concentration in the models.

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This paper suggested one method to analyze an impact response of a beam, based on not supposing external force but considering motion of a mass. The analysis is carried out by using the law of conservation of momentum in the case of considering a mass as a rigid material particle, meanwhile, by connecting a mass to a beam at an impact point in the case of considering a mass as an elastic body. From the comparison of present results with experimental ones by Matumoto et al., the availability of this method is clarified. Also, it is shown that chattering, i.e. re-collision between a mass with a beam, can be treated.

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Tactile wear (of "Tezure" in Japanese) is the wear phenomenon generated by the touch of the human hand and skin over periods of 100 hundred to several hundreds of years. Tactile wear can be observed in objects of daily use, but particularly in statues of Buddha and St.Peter that are frequently touched by believers, as it was announced in the previous report. Then, friclional wear characteristics for various soft metals against human fingers are reported in this study.

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In the pipe systems of atomic or power plants, pipe bends absorb the longitudinal thermal deformation. At the center section of pipe bend, ovalization occurs and high stress concentration is observed in the circumferential direction. In this study, the large deflection of the pipe bends under in-plane bending analyzed by the finite element method using a mathematical proframming method. Numerical examples are shown for pipe bends with different radius ratios and pipe factors.

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Cylindrical shell is one of the typical thin shell structures , and because of its mathematical simplicity, many structures such as oil tanks and straight pipes are made with cylindrical shells. In this investigation, the finite element analysis of cylindrical shells is studied with curved cylindrical elements using Hermite interpolation function. Numerical examples are shown for a benchmark test and practical oil tanks subjected to wind load.

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As for the dynamic problem, some analyses are approximately carried out by use of infinitesimal deformation theory even if large deformations are allowed. Therefore, the limit of applicability of infinitesimal deformation theory need be known. In this paper, the behavior of simply supported beam under collision of impactor with different velocity is analyzed using both theories. So, the quantitative difference between the both results on time proceeds depending on initial velocity of impactor is shown, and the limit of applicability of infinitesimal deformation theory is examined.

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In this paper, the numerical method for anticracks (rigid lines) by the singular integral equations method is presented. In formulating the anticrack problem, concentrated forces are distributed continuously on the anticrack surfaces and the boundary conditions on the anticracks are reduced into a set of singular integral equations in which the densities of the concentrated forces are unknown. Furthermore, the numerical technique for the singular integral equations is developed, in which the boundary conditions (singular integral equations) are made to be satisfied at suitably selected collocation points. The rapid convergence and the accuracy of the numerical solutions have been verified by some examples.

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The photoelastic coating method is one of the most practical engineering ways to study the elastic-plastic behaviors of metals under the plane stress. However, the separation of the strain differences at loading steps is difficult using the isochromatic fringe pattern. The authors conducted the uniaxial tensile test of a thin plate with a central flat hole by the photoelastic coating method. Finally, isothetic lines obtained by the finite element method and the isochromatic fringes are compared.

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In the previous papers, the authors evaluated the evolutions of surface roughness of pure aluminum specimens made of several different grain sizes using the Laser speckle method. Then, it was obtained that the expansion of the speckle intensity distribution, i.e. evolution of surface roughness, was increased with the growth of the grain size of specimen. In the present paper, the above result is examined again via the comparison of surface roughness evaluated by the Laser speckle method with Finite Element Polycrystal Model plasticity deformation analysis.

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Intelligent/smart structures are now notable as basic components in the field of micro machine technology and micro manufacture. One of practical materials for intelligent/smart structures is a piezoelectric material which works as deflection sensor and as deflection actuator, simultaneously. In the present paper, the deflections of the box typed piezoelectric cantilever are analyzed by FEM using its electric fields, and then actuated to the objective position by controlling the electric charge.

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The dislocation behaviors, i.e., density of mobile dislocations and eigen frequency of dislocation strings, are closely related to fatigue damage of materials. We can estimate the density of mobile dislocation by measuring ultrasonic wave velocities of three-different frequencies via Granato-Lucke's dislocation string theory. In the present paper, the correlation of the mobile dislocation density with fatigue damages of aluminium alloys and chromium-molybdenum alloy steels was examined.

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Although stress and strain states are same in simple and pure shear states, longitudinal wave velocity changes propagating in the plastically deformed medium under simple and pure shear states are apparently different each other as the results of authors' theoretical and experimental research works. The objective of this paper is to discuss the effect on ultrasonic wave velocity changes due to texture and cross slip under simple and pure shear states via finite element polycrystal analysis. First the texture developments under both states are studied and the results suggest the dependence of transverse wave velocity changes on texture in the small plastic deformation range. Next, the multiplicative amounts of intersected slids between primary and secondary slip systems, which relates closely to the amount of cross slip under both states are calculated and the results show that the point defects induced by cross slip are much easier to be introduced under pure shear state than that under simple shear state, this suggests that the point defects induced by cross slip may cause quite different longitudinal wave velocity changes.

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A microcracks near surface of the cancellous bone causes origin of bone fracture. Therefore, to prevent a bone fracture and/or to toughen a bone structure it is important to evaluate mechanical bone property near microcracks in trochanter major and minor sides. In this study, mechanical bone properties density, elastic modulus and Poisson's ratio, around microcracks near surface of the cancellous bone at a human trochanter were examined via measurement of surface wave velocity and acoustic impedance using a scanning acoustic microscope (SAM).

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In this paper, the method of deciding stress intensity factor is described by using strain gage. The type of the strain gage used by this experiment is the gage length of 0.2mm. The CT test specimen of the FRP material was used for the experiment and the tension speeds executed at the speed of 0.05, 0.1 and 0.2 mm/min, and executed the experiment temperature at 30℃. The experiment result and an analytical solution were compared. It was shown that the proposed method of strain gage was able to measure the stress intensity factor of the crack by adequate accuracy.

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The influence of friction time at joint interface on the growth of intermetallic compound layer by post-weld heat treatment (PWHT) at 580 ℃ of pure titanium (Ti)/commercially pure aluminium (A1050), and Ti/highly pure aluminium (AN4) friction weld joints was investigated with direct observation method. The layer growth rate was depended on neither linear nor square law. The layer growth rate of Ti/AN4 joint was faster than that of Ti/A1050. This was due to the difference of Si content between A1050 and AN4 substrates. There was slight difference in the layer growth rate between the both joints that were welded with friction times of 2 and 7s, respectively. Furthermore, the plateau stage appeared on the layer growth after heating of approximately every 10 hours during PWHT.

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The study was carried out on the ageing behavior of 7075 aluminum alloy deformed at cryogenic temperature, i.e. 77 K corresponding to liquid nitrogen temperature, in order to improve its mechanical properties. It can be seen that pre-ageing at ambient temperature affects final ageing process. Hardness is increased by deformation in proportion to work hardening exponent, while there is inverse relation between the magnitude of final age hardening and work hardening exponent. Hardness is somewhat increased by deformation at cryogenic temperature, while its effect is so smaller than expected.

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This report describes effects of friction time, diameter of the base metals and age-strengthened heat treatment after joining (ASHT) on the mechanical and metallurgical properties of Al-Zn-Mg-Cu alloy (A7075) friction weld joint. The joint tensile strength decreased with increasing friction time from 0.5 to 6s in as-welded (AW) and ASHT conditions. The strength was increased approximately 50MPa by ASHT than that of AW joint. The width of the softened region occurred during friction joining operation, i.e., solution treated region, increased with increasing friction time. The hardness of the softened regions could not recovered to that of as-received one by ASHT. There was slight difference in the distributions of the softened regions among 8, 12 and 16mm diameter joints. The hardness of the softened regions could not also recovered to that of as-received one by ASHT. This reason can be explained as the size, number and distribution (dispersion) of precipitates in crystal grains, or at grain boundaries.

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This report describes the effects of faying surface conditions beforejoining, especially, the thickness of oxide film, on the tensile andmetallurgical properties of oxygen free pure copper (OFC)/pure aluminium(Al) friction weld joint. The joint tensile strength decreased when thethickness of oxide film on both materials before joining increased and alltensile specimens fractured at the joint interface between OFC and Al. Theoxide film on OFC decreased the joint strength more than that on Al substrate. This is due to the difference of the deformation resistance between OFC and Al. That is, OFC hardly deformed during friction joiningoperation, however, Al substrate deformed out as collar. While the joiningstarted at periphery side, and propagated toward center axis portion when OFC surface was oxidized, it started from center axis when Al surface was oxidized.

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A high-sensitive tiltmeter which consists of a simple optical system with a laser diode and a quadrant photo diode detects a minute crustal movement as the angle of tilt. In this system, slight misaligment of the optical system emerges as skewness of the laser spot. In order to reduce this skewness, we changed reflectors from the surface of hydrargyrum to a mirror placed on the viscoid liquid. We experimentally evaluated a change of the sensitivity as a function of direction of the laser spot displacement. The experimental results show the improvement in the skewness of a laser spot. This system contains 4.3×10^<-7> [rad] accuracy for detecting the tilt angle.

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To realize autonomous manipulators which work outdoors, 3D vision sensors are required to measure objects and environments under severe conditions. The authors have proposed a real-time motion stereo vision which measures 3D coordinates of objects with simple calculations based on brightness gradient of images captured by a motion camera. In this paper, firstly, factors of the measuring errors are investigated in detail and improved. Secondly, the camera velocity is improved to reduce the effect of object movements. Finally, in consideration of installation in manipulators, a downsized motion stereo vision is fabricated and tested under measuring experiments.

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A color can be shown as the data on the numerical value if the quality of the printed matter is analyzed and a fixed quantity can turn. If there is accumulation of the data, it becomes possible can to control a printing machine directly by making feedback to the cause and to be completely automatic and to print it. It is a purpose to make the system which can analyze the quality of the printed matter from the viewpoint of numerical value by this research for the above reason. But, when a color is actually measured, an error with the theory value arises. So, the preparation of the program of correcting the error for color matching this time and the consideration of the data were done.

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To investigate the condition of blood circulation in a living body, we performed measurements of the spectral reflectance in the visible wavelength (380-780 nm) for a model of human skin tissue and analyzed color apperance. Experiments in vitro were carried out using Intra-lipid 10% which contained a very small quantity of blood to represent a capillary network in a random scattering medium. Measurements in vivo were performed during cuff occlusion of the brachial artery. We found from comparison of results in vitro and in vivo that the color appearance of skin tissue changed according to the blood oxygenation and concentration.

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A novel polarized-type phase Doppler method is proposed for measurements of the absorption coefficient as well as size and velocity of moving particles. The particle diameter is obtained from the phase difference between the reflected and refracted rays separately detected in a single scattering direction by using the polarization technique, while the absorption coefficient can be determined from the intensity ratio of reflected and refracted components in a single burst of Doppler beat signals. We numerically estimated the accuracy in measurements of the absorption coefficient in relation to some optical conditions such as the beam waist diameter and the direction in which the photodetector is located.

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The usefulness of the polarized-type phase Doppler method for simultaneous measurements of particle size and absorption coefficient was confirmed by experiments using water-black ink droplets whose concentration was known in advance. The particle diameter is obtained from the phase difference between the reflected and refracted rays separately detected in a single scattering direction by using the polarization technique, while the absorption coefficient can be determined from the intensity ratio of reflected and refracted components in a single burst of Doppler beat signals. We estimated the accuracy and sensitivity in measurements of the absorption coefficient and, moreover, considered a solution to the 2π-ambiguity of signal phases in determination of the particle diameter.

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At present, printing machines adopted various electronic control technology and it gives great effect for saving labor, skill-less, improvement of the labor environment, and so on. But, as for the printing industry, a global management system which used network and database isn't realized. So, Database AMPAC is proposed as a means which realizes a global management system in the whole of the printing industry. The printing information is stratified systematically and it is being encoded at Database AMPAC, the search and decision value of the setting point of each printing machine for the change of the parameter by applying this to the usual system and employing it become possible. We made a program that is a automatic adjusting simulation for printing machine by using the Java language and CORBA.

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The designing process of products, the workflow management of production process and the initial adjustment of production facilities require the participation of experts. It is necessary to analyze knowledge of the expert skill and to describe with a format suiting to the integration in order to imitate their high level skill. The Database MPAC prepares the most suitable data description format for the purpose. The data in AMPAC coding includes the relation between the parameters, so the inverse searching algorithm of the related parameters can be easily composed. The inverse searching is the basic procedure for initial adjustment. The information relating to the production process including the expert skill in the initial adjustment process is described by using AMPAC format at the first. Next, the inverse searching is performed and the adjusting points on press machine are indicated, when an alternating parameter is given.

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The breeding system is supposed that animals, plants and the like are breeded at the limited area and the resources. Cellular automata method is used to think of making breeding system. In this study cells is liken to animals or plants. These biomasses prey or are preyed on other animals or plants in a established area. Rules is set upped as a relationship of biology. A purpus of this study is to consider about connection between set upped rules and transition of a total number of cells as biomasses.

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This paper studies the disturbance cancellation control to suppress a vortex-induced vibration (VIV) of a circular cylinder in a cross flow. We propose an external force model based on the two modes of the vortex pattern of the wake, i.e. Karman vortex street mode and 2P mode. The appearance of the vortex pattern modes depends on the flow rate and the amplitude of the cylinder. The external force to the cylinder is derived from the complex potential of the flow field. The disturbance cancellation control is applied to the cylinder with elastic supports under VIV. The external force is assumed as a harmonic excitation force whose period depends on the flow rate and the amplitude of the cylinder. Numerical simulations are carried out and we confirm that the control method is effective to reduce the vibration amplitude of the cylinder.

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Periodic stimulation sometimes stabilizes mechanical systems dynamically. We have investigate an inverted pendulum system from a view point of such a dynamic stabilization. In this paper, we present the dynamic stabilizatin control that stabilizes the pendulum in a desired limit cycle by a periodic input.

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Synchronous position control method has been already designed simply and applied in mechanical manufacturing fields. In this paper, Synchronous position control method is the first case, which is applied to the docking system of Microsatellite to be captured rapidly and accurately. It is conceivable that the outline control of high accuracy will be achieved and the reliability of docking system will be improved. We carried out the one-dimensional numerical calculation. As the result, this method is useful and feasibility to the Microsatellite docking simulation.

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Recently, a technique has been developed to increase stiffness and strength additionally to already existing structures. This reinforcement is made possible by bonding the fiber reinforced plastic (FRP) sheets on the surface of structures. This technique has advantages in the cost performance and easiness of the operation. Although it has been used mainly for concrete structures in civil engineering, it is now considered to apply to metal structures. The analysis is based on the classical plate theory and Ritz method, and optimal design for the maximum frequencies is considered.

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This paper presents the free vibration analysis of stiffened, FRP laminated circular cylindrical shells by transfer matrix method. For this purpose, the governing equations for vibration of the shells are derived according to Classical Lamination Shell Theory, and the equations are written as a coupled set of first-order differential equations by using the transfer matrix of the stiffened shells. Once the transfer matrix has been determined by the numerical integration of the transfer matrix equation, the frequency equations are derived in terms of the elements of the matrix. The method is applied to stiffened laminated circular cylindrical shells and natural frequencies are calculated numerically. The effects of stiffener and stacking sequence on the vibration characteristics are also studied from the comparison of frequencies obtained for various shells with different stiffeners and stacking sequences.

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This paper studies a position and force control for a flexible manipulator considering the contact with environment. Stiffness of the environmental surface is expressed by using spring stiffness and viscous damping. Equations of motion of the arm are derived for the non-contact, contact and constraint cases. State equation is obtained by means of linearization and the optimal servo approach is applied to the system. Validity of the present method is examined by numerical simulation of the movement of the arm.

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This paper presents the maximization of fundamental frequencies of FRP laminated circular cylindrical shells by Genetic Algorithm. For this purpose, the frequency equation for a simply-supported laminated shell is derived based on Flugge-type classical lamination theory, and then two types of optimization problems for the shell are formulated by defining continuous design variables and by discrete design variables, respectively. Two kinds of GAs are also applied to solve these optimization problems. In numerical experiments, optimal design solutions are obtained for various laminated shells with different stacking sequence, and the maximization for the frequencies of the shell is also studied from the comparison of numerical results obtained.

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This paper studies the structural optimization with robustness for buckling of FRP laminated circular cylindrical shells. For this purpose, the buckling equation under axial compression is derived based on the classical lamination theory, and multi-objective optimization problem is defined by taking a critical buckling load and a sensitivity of the load as objective functions, and the bucking load and the sensitivity would be maximized and minimized simultaneously, respectively, by optimizing the stacking sequence of the shell. In optimization, a vector evaluated genetic algorithm is employed to solve the optimization problem. In numerical calculations, the pareto optimal solutions are obtained for the present problem, and the applicability of the GA employed is also studied from numerical results obtained.

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This study presents an analysis of function for snow melting machines. Although the use of snow melting machines rapidly expands these days, the design guideline for snow melting machines has not yet been established well due to shortening of the development period and diversify of needs. As a first step to establish such guideline, function of various components included in the machines is analyzed by using the DEMATEL (DEcision MAking Trial and Evaluation Laboratory) method. The results are shown in the form of vector graphs to explain mutual relations among component functions.

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Under the conditions of the periodic changes in supply pressure and loads, tribological characteristics of spherical bearings for hydraulic piston pumps and motors were examined experimentally using four types of piston assemblies. The apparatus consisted of a piston assembly with the spherical bearing tested, a bushing equipped with eight hydrostatic bearings, an electric motor and the hydraulic circuit. The diameters of the spheres tested were specified by 7.9, 9.5, 12.7 and 15.9 mm. The maximum supply pressure was 4.9 MPa, the maximum frequency of the sinusoidal and rectangular fluctuation was 1 Hz, and the speed of rotation was 10 s^<-1>. Hydraulic oil of ISO VG 32 was used as the test liquid. Frictional torque and leakage flow rate were measured. In conclusion, the frictional torque notably decreased and the squeeze film effect was recognized for the case of the change in the supply pressure and loads being the rectangular wave with high frequency.

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This study deals with the system of texture grinding on sliding surface of ski. PE (Polyethylene) is used for the material of sliding surface because it is well balanced with low friction, macinability and price. To reduce friction, fine grooves called "structure" are carved on sliding surface. In this study, it calls "Texture". Texture is thought to control the amount of water that is generated by frictional heat between sliding surface and snow surface. By examining frictional heat, mechanism of moisture generating is shown and fundamental phenomenon toward optimization of texture is obtained. The state of generating water varies greatly by the conditions of sliding. Moreover, some experimentation about water repellence and measurement of coefficient of friction are made. Differences of water-repellency and coefficient of sliding friction by the difference of texture are detected.

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In the optical shape measurement process, the distinctness of measurement shape data is much influenced on resolution of the sensor , and it is difficult to discriminate the change within the limit of resolution. The measured data requires some mathmatical treatments with detected its characteristic weighting function to get back its original shape data. In the present investigation a simulation to makesure the availability of the weighting function method. In the simulation, there are no problems turned up by using completely smooth data. On actual measuring , a step gauge measuring instrument is used. The data output by the laser instrument has much noise and its weighting function does not have a fixed shape. Therefore it is shown that making distinct dull data from a sensor may be possible although more devices are needed.

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Composite materials have been watched for centering the future of materials technology. FRP which is reinforced by the fiberglass have been used among many field. Product method of the FRP has characteristics, then, the material is hard to recycle and dispose of. In this study, we try to separate of milled FRP into Glass and Plastic for the purpose of recycling of FRP. We use difference of specific gravity of Glass and Plastic in liquid to separate.

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