Product architecture is basically the engineering or product design concept, but it has a potential to change the business environment which the firm is in the face of. It especially effects on the firm's knowledge management. From the case studies of TDK in HDD industry and Mitsubishi Kagaku Media in optical storage media industry, this paper considers how firms should manage the product architecture, their knowledge and their business strategies.

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This paper presents applications of multiobjective design optimization (MDO) and multiobjective design exploration (MODE) in space engineering. These applications include hybrid rocket conceptual design, spacecraft trajectory design, rocket engine design and aerodynamic reusable sounding rocket design. This paper also discusses limitations of current MDO and MODE and presents real-world design optimization test problems and a new approach to extract useful design information from non-dominated solutions of optimization problems.

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This paper proposes the state-of-the-art functions of process automation and optimization software. Four topics, optimization algorithm, process automation, approximation algorithm and simulation data management, are described. Functions of these topics are improved according to requests of engineers who use process automation and optimization software in their design, research and development jobs.

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Noninvasive cortical dipole imaging is one of the spatial enhancement techniques from the scalp electroencephalogram. We investigated the dipole imaging for multiple signal sources under time-varying non-uniform noise conditions. The parametric projection filter that incorporated with noise covariance was applied to the inverse problem of EEG measurements. The noise covariance matrix was estimated by applying independent component analysis to the scalp potentials. The proposed imaging technique was applied to human experimental data of somatoseosory evoked potentials. We obtained reasonable results that coincide to physiological knowledge.

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This paper describes human perception control by means of auditory information from active viewpoint. As an active perception control problem, we first investigated the lifting force characteristic for when a person hears auditory information. We applied the knowledge gained from those experiments to the operation support of electric wheelchair, cello, drilling machine and car. In future work, we must consider how to design sounds that are more appropriate for the desired actions.

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This paper represents the preliminary study on the subliminal visual information for guiding driver's attention to hazardous factors in the driving roads. This study is based on measuring subjects' performances simply under subliminal environments. Author concludes some effect to improve subjects' behavior with subliminal visual marks. To analyze the effect of subliminal information, measurement and evaluation of higher brain function will be needed.

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In this paper, the elastic-plastic collapse of thin-walled rectangle tubes subjected to torsional loading is studied by using the finite element method(FEM).It is found that there are three collapse modes. The firstmode is a collapse due to elastic buckling. The second mode is a collapse due to plastic buckling. The third mode is a collapse due to denting of the cross section. Based on these facts, approximate numerical methods to estimate the peak torsional moment are proposed, and their validity are verified by comparing with the numerical results by FEM under various conditions.

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Previous researches have been proposed evaluation methods of the maximum moment for pure bending. Moreover evaluation methods of the ultimate load for thick walled square tubes subjected to bending and compression have been established. However evaluation methods of the ultimate load for thin walled square tubes subjected to bending and compression have not been established yet. In this paper, the ultimate load of square tubes subjected to bending and compression are studied by using the finite element method. It is found that there are six types of collapses. Based on these facts, an approximate numerical method to evaluate the ultimate loads for square tubes subjected to bending and compression is proposed, and its validity is verified by comparing with the numerical results by FEM under various conditions.

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In this paper, the indenter is penetrated into an anisotropic elastic half-space with a pattern, and then a tangent force is applied to the indenter and judge a pressure distribution region and the relations of the shearing force. The partial slip contact problem was solved by a numerical procedure based on the conjugate gradient (CG) method and fast Fourier transform (DC-FFT) method. It is shown that the High shear stress and pressure occurrred at a corner of the surface pattern.

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In this paper, contact analysis for anisotropic elastic layered half-space is performed using surface Green function considering surface and interface property. The discrete convolution and fast Fourier transform (DC-FFT) method and conjugate gradient (CG) method were used for conducting the contact analysis. The contact analysis was conducted for investigating the effect of thickness of thin films and material of substrate on the penetration depth for the rigid spherical indenter.

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Analytical solution for anisotropic hollow cylinder subjected any loadings at lateral surfaces has been not derived so far whereas solution in case of an isotropy was obtained. Even in the case of isotropy, antiplane loading is not yet treated. In this study, the general solution for anisotropic hollow cylinder is shown using a complex stress functions based on Lekhnitskii formalism. Stress functions are derived using a constraint release technique, which is a kind of the convergence numeration applied for the problems of solid cylinder and infinite medium with cavity. Any loadings, for example, distributed load such as hydro pressure and concentrated load are taken into account a stress function developed a Laurent series. Example calculation is shown in several graphical representations.

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This study, by applying the finite element method for incompressible viscous fluid, calculated using the GPU. In order to perform calculations on GPU, using the CDS format for sparse matrices. The CDS format, can be calculated for high-performance vector computers. Numerical examples, the problems 3D Cavity flow, steady state at Re = 1,000 and non-steady state at Re = 3,200 is calculated. Appleyed the number of nodes is calculated by 32 x 32 x 32, 64 x 64 x 64 and 128 x 128 x 128 hexa mesh. The matrix solution, results calculated using the method measures the rate of conjugate residual (CR) method, part of the SpMV, calculated by the performance of the 36Gflops. This approach, by finite element method for fluid analysis, proved to be a high efficient method for calculating the GPU. These results were obtained CUDA version 4.0 using a NVIDIA GeForce GTX580 1.5GB memory.

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The products are needed to function under various outdoor circumstances. In some cases, they have to resist hail impact. It is difficult to reproduce hail impact because hail falls at a speed of dozens meters per second. If the stress by the hail impact is obtained analytically, it is useful for reliability design against hail. In this study, the stress evaluation of the glass hit by ice ball using impact analysis was performed to predict the stress hit by the hail. As a result, it is concluded to predict the stress hit by ice ball using impact analysis regarding ice ball as elastic perfectly plastic solid.

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Toward the phenomenological understanding of laser welding repair processes for various reactor components by numerical simulation, we constructed laser welding simulation code which can treat combined physical phenomena including interfaces, a phase change and stress evaluation in solid materials using several advanced numerical models. In the calculations of low-power density laser welding, we obtained particular results in the welding, e.g., thermal-shaped molten pool, a welding bead and a stress distribution around the molten pool. Therefore, our numerical code will be appropriate tool for elucidating laser welding phenomena in the near future.

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Sleep is necessary for human health and acttivities. Recently, the sleep problems have become matters of public concern. There is a report that 20 percent of Japanese people have sleep problems. Therefore, the topic of sleep problems have been taken up by the media and increased the number of topics about bedding and bedroom. In particular, pillow have received much attention of many people. The clinical reports showed that pillow is one of the factor for sleep problems. And this report says that sleep problems are related to the height of the pillow. However, there is little for engineering approach about sleep problems and pillow. In this study, stress distribution analysis was done for clarifying mechanical relation of the pillow and cervical vertebrae on spine position. The experiment used 2 dimensional and 3 dimensional photoelastic method. Specimen model was prepared by reference to clinical report. The experimental results shows that concentration notably appeared near the first and sixth cervical vertebrae.

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Knee sport taping is frequently used to protect the anterior cruciate ligament (ACL)-injured knee in sport athlete. The purpose of this study was to investigate the effect of sport taping for ACL injured knee on knee stiffness. In 10 young people with intact knees, anterior tibial translation were recorded at four anterior drawer loads (44, 66, 88, 132N) under two conditions (with or without knee sport taping) using knee arthrometer. The results showed that the sport taping limited the anterior tibial translation compared to without taping. However, the efficacy of taping was deteriorated by light exercise such as walking.

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After the total knee arthroplasty, it is important to evaluate between the patella component and the femoral component, because patella components affect the complications and the flexion angle. The purpose of this study was to investigate the mechanisms of contact between the patellofemoral joint. Femur and tibia were created by aluminum alloy. The implanted knee model was constructed to replace the cruciate-retaining artificial knee joint to them. Artificial ligaments were used as quadriceps model and patellar tendon model. The contact pressure were measured at seven flexion angle (90 degree, 100 degree, 110 degree, 120 degree, 130degree, 140degree and 150 degree) under the applied loads of 1000N. In result, the contact pressure was considered to increase with rising flexion angle, but such a phenomenon was not showed. It is possible that not increased contact pressure is effect of contact between femur and quadriceps. Understanding the advantage and disadvantage of the patella component function may help to develop sophisticated component design.

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The purpose of this study was to investigate the relationship between mechanical properties and passive electrical property for articular cartilage. In the present study, the magnitude of admittance IYI was used to evaluate passive electrical property. Cartilage specimens without subchondral bone were taken from porcine knee joints with biopsy punch with 6 mm diameter. The specimen of 1.2 mm thickness was firstly prepared and its magnitude of admittance IY1 was measured. This specimen was then sliced from 1.2 mm to 0.9 mm thickness and then again from 0.9 mm to 0.6 mm, and its magnitude of admittance I11 was measured at each thickness. The magnitude of admittance IYI for the specimen of 1.2 mm thickness was measured under 20 and 40 °C. The magnitude of admittance III is constant at high frequencies and variation of the saturated value with thickness and temperature of the specimen were observed at high frequencies. These results showed that passive electrical property of cartilage can be evaluated by the magnitude of admittance III at high frequencies. Electric impedance measurement and stress-relaxation test were carried out for the same specimens of 1.2 mm thickness to evaluate relationship between the passive electrical property and mechanical properties obtained using three elements model. The magnitude of admittance 1/1 showed a significant negative correlations with elastic modulus El(r = -0.704, P<0.05), elastic modulus E2(r = -0.704, P<0.05), and viscosity coefficient ri(r = -0.689, P<0.05) respectively. These results showed that mechanical property of articular cartilage can be estimated by using an electric impedance method.

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It is important to examine the tribological maturation of regenerated cartilage for planning the after-treatment. In the past experiment, we reported that hydration-lubrication-like phenomenon of the cartilage can be measured by using the MPC (2-methacryloyloxyethyl phosphorylcholine) polymer grafted surface as a counter face of frictional test. This paper evaluates frictional properties and maturation of regenerated cartilage by using MPC-polymer grafted surface. The regenerated cartilage was prepared by seeding chondrocytes from 4 weeks old Japanese white rabbit onto fibroin scaffold. The friction test was carried out by reciprocating friction apparatus using saline solution as the lubricant with applied normal load of 300 N (about 0.15 MPa), and with the sliding velocity of 0.008 mm/s, 0.08 mm/s, 0.8 mm/s and 4 mm/s. The load was applied for 600 seconds before the sliding began. The result showed that friction coefficient of regenerated cartilage was significantly lower than that of the control specimen but higher than that of the normal cartilage at 7 days and 14 days culture. These results showed that chondrocytes regenerated lubricating function but it is not matured as normal cartilage in 14 days cultivation.

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Early detection of fracture risk is important as effectiveness of treatment with bone diseases. Over the years, loss of bone mineral or bone mass has been considered the major cause of bone fractures. However, recent studies suggest that collagen also contributes to bone strength by using physiological and artificial aging bone. It was found that fracture risk is related to not just a simple loss of bone mass, but related to significant changes in the biochemical and physical properties of the collagen matrix. Therefore the microscopic interaction between the mineral and organic material may determine the mechanical properties of bone. In this study, bovine cortical bone specimens with different ages were analyzed by Raman spectroscopy. As the results, Raman spectrum of bovine cortical bone with different mechanical properties with aging showed the different Raman spectrum with aging. The effectiveness of Raman spectroscopy was confirmed as a technique for the mechanical evaluation of bone aging.

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Cortical bone has a hierarchical structure. In microstructure, cortical bone is a composite structure of the osteonal and non-osteonal regions and it is regarded as "osteon composites". In nanostructure, cortical bone is a multi-phase nanocomposite material consisting of collagen and hydroxyapatite (HAp). The relationship between the mechanical properties and the hierarchical structure of cortical bone has not been fully investigated and elucidated. This study used strip specimens aligned with the bone axis taken from the cortical bone of a bovine femur. In the experiments, elastic modulus and strength of the specimens were measured by tensile tests. The degree of c-axis orientation of HAp crystals in the specimens was measured by X-ray diffraction method. The area ratio of osteonal region at the cross sections of the specimens was determined. Indentation tests using an AFM probe were conducted at the osteonal and non-osteonal regions in the cross-section. As a result, the elastic modulus and strength were higher in specimens with lower area ratio of the osteonal region. Indentation tests show that the contact stiffness of the osteonal region was lower than that of the non-osteonal region; however, the difference was not so large. The degree of HAp orientation was higher in specimens with lower area ratio of the osteonal region. Furtehr, the elastic modulus in the bone axial direction depended on the degree of c-axis orientation of HAp crystals.

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Metal-on-polyethylene hip prostheses are widely used for total hip arthroplasty in the world. However, for many of these metal-on-polyethylene hip prostheses, the polyethylene wear and subsequent osteolysis have been reported to cause loosening between the prostheses and bony interfaces. Therefore, metal-on-metal hip prostheses, which have recently received much attention, can offer such advantages as follows: improving antiwear properties utilizing fluid film lubrication, which is achievable with processing for higher accuracy shape and surface finish and selecting more suitable clearance, and inhibiting dislocation by use of large diameter heads. In this study, tribological behavior of metal-on-metal hip prostheses was evaluated using the electric resistance method with hip joint simulator during walking condition. Because the cup and head are in direct contact during initial loading, the results show that fluid film lubrication should be used after initial wear. In addition, measuring the degree of separation was also succeeded by using the bovine serum lubrication.

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Mineralization is an essential function for life, and bone is one of the most important tissues for vertebrates. Elemental process of bone mineralization has been studied anatomically for long time. However, the elemental mechanism of bone formation, and mineralization process are still unknown. Because bone mineralization is the final product of cell proliferation, cell migration, cell differentiation, protein secretion, matrix construction, and tissue calcification; to clarify the bone formation mechanism, a dynamic approach through the use of anatomical knowledge seems necessary. In this study, we developed a computational model of in vitro bone mineralization of mesenchymal stem cells (MSCs) and simulated the process of the bone tissue formation. MSCs have in vitro osteogenic differentiation capability, and the constructed in vitro bone tissue is very similar to the in vivo one. At first, we analyzed the spatial patterns of proliferation, osteogenic differentiation, and mineralization of MSCs. Then, we designed the computational model which consists of two steps, i.e. osteogenic differentiation and mineralization, with JAVA programming language according to the analyzed spatial pattern. We adjusted the simulation parameters by comparing with the in vitro process of bone tissue formation. These parameters are considered as important factors for understanding the dynamic formation pattern of bone tissue.

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Currently lasers are used to destroy Birthmark and Lentigo in clinics of dermatology and plastic surgery. The aim of laser therapy is to destroy the target cells and not to harm the surrounding tissue. We have developed a new type of laser apparatus for removing only the pigmented lesions with laser scanning technology. The effects of a Nd:YVO4 laser (1064 nm) with a laser spot size of 30 gm in diameter was investigated by experiments with rats. As a result, the pigmented lesions were able to be removed but some scar tissues were formed. The thermometry during the laser irradiation was performed with an infrared thermal imaging camera. It was found that the temperature rise by laser irradiation reached the temperature that was high enough to cause a burn. Thus, to resolve this problem a new irradiation method in which the focused laser beam was scanned with each laser line 150 gm apart was proposed.

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Endoscopic sinus surgery is generally performed as the means of treating inflammation of the sinus. However, there are risks that the tip of endoscope enters in the eyepit, and the eyeball and the optic nerve are damaged. In this study, the vibration of the eyeball caused by a surgical tool for endscopeic endonasal sinus surgery was measured with a Poly Vinyliden DiFluoride (PVDF) film during surgery. The eyeball showed characteristic vibration when the surgical tool was getting closer to the eyepit. In order to examine the difference of the vibration between right and left eyeballs, the vibration of the eyeball was analyzed by FFT, STFT, and panpot analysis. The result suggest that the frequency spectrum show different patterns according to the types of surgical tool, and the panpot spectra indicate to which eyepit the surgical tool is getting closer. The developed program can estimate the position of the surgical tool and analyze its frequency of vibration at the same time.

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Abstract The swimming motion of Tuna type fishes has excellent ability for its speed and efficiency. Many studies are conducted for Tuna or Dolphin swimming motion, and some motion schemes are proposed. But, many of developed swimming robots have spring held tail fin, and it moves passively by the force of flowing water. Therefore, our target is to develop swimming robot which has actively driven tail fin, so as to verify former studies in the meaning of drive efficiency. This paper shows the detail of our prototype swimming robot which was made to evaluate motion control system.

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This paper reports on direct measurement of differential pressure distribution on a butterfly wing during takeoff. Differential pressure was measured with a micro-fabricated sensor. A MEMS (Micro Electro Mechanical Systems) piezo-resistive cantilever was used as the differential pressure sensor. The sensor chip was 1.0 mm x 1.0 mm x 0.3 mm in size and 0.7 mg in weight. The sensor was attached to a butterfly (Papilio protenor) wing surface through a Cu/Polyimide substrate and Au wires. The total weight was 30 mg so that it did not interfere with flight condition. The distribution of five points to the spanwise direction at the forewing and one point at the center of the hindwing was measured during takeoff. As a result, it was clarified that the maximum differential pressure was 20 Pa on the forewing tip. Additionally, the maximum aerodynamic force generated on the wing was 3 times larger than the gravity acting on the body.

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To investigate microscopic dynamics of aortic rupture, we developed a device which enables to observe the dynamics with a microscope equipped with an equibiaxial tensile test system. A metal cylinder 6 and 8 mm in inner and outer diameter, respectively, was placed above the center of a thin-sliced specimen held with a circular metal frame 10 mm in inner diameter. The frame was vertically elevated until specimen rupture while measuring force loaded on the frame and taking images of the specimen. Stress and strain were measured from the force and the displacement of the markers on the surface of the specimen, respectively. Silicone rubber was stretched until rupture as an example of homogeneous isotropic material. Images of the specimen during the test were clearly observed through the cylinder. Elastic modulus of the silicone was obtained to be 1.9 MPa, which was comparable to a typical value of the material. The coefficient of variation of strains was 3%. We then applied this test system to specimens obtained from the porcine thoracic aortas. Stress at strain of 0.5 and tensile strength were comparable to those reported previously. The coefficient of variation of strain in the aortic specimen was 7%, and was significantly larger than that of silicone rubber, indicating that the aortic specimens are inhomogeneous. The developed device could provide reliable mechanical properties and was useful for observing specimen under microscope in an equibiaxial state.

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A novel self-regulating drug release system was fabricated and tested. The system consists of two units: decompression unit so-called "organic engine" and drug release unit. Glucose oxidase (GOD) immobilized membrane was utilized to "organic engine" for converting chemical energy of the glucose to mechanical work as a pressure changes of consumed oxygen in the GOD reaction. Pressure changes caused by GOD reaction of the decompression unit was in good correlation to the glucose concentrations. Afterward, the drug release unit which utilizes the energy of the "Organic engine" as a power source was fabricated and evaluated by recording its release actions. The system was then fabricated by combining the both units. As an evaluation result of the system, the feasibility of feedback control of glucose concentration by the chemo-mechanical drug release system was shown.

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1/f'a(0.5<a<1.5) noises are observed in life systems. It is known that the slope of power spectrum density (PSD) in 1/f noises of life systems varies by age and disease. We can expect that 1/f noises are applied to the diagnostic technology. However, the generation mechanism of 1/f noises is not fully disclosed so far. In this study, we propose the generation model of 1/f noises from the superposition of first-order autoregressive (AR(1)) models, and conduct numerical analysis using the proposed model. Moreover, we attempt the explanation of the generation of 1/f noises in cell-membrane potentials and diffusions in multi-cellular systems. In results, we obtained the 1/r (a,--0.75, a4.99, az-1.21) noises, respectively. We suggested that 1/f noises are generated by the superposition of AR(1) models which has different dissipations. It is suggested that 1/f noises are arisen in multi-cellular systems.

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Microbial fuel cells (MFC), which convert chemical energy of organic compounds to electric energy, have developed in recent years. MFCs may play an important role in sewage plants, where organic compounds in sewage are removed by microbes. We examined three kinds of sewage, i.e. inflow sewage that flowed into the plant, precipitation sewage, which was obtained by removing solid particles by precipitation from the former, and activated sludge, which was mixed with microbes and incubated to remove organic compounds. We observed the maximum electric power, 0.33 gW/cm2, in the inflow sewage. The output of the MFC depended on the kind of the sewage and stored time of the sewage. It was suggested that some microbes in the sewage enhanced the performance of the MFC.

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In this study, two analyses of stress distribution and principal stress chart in an automobile hub on cornering force were done by photoelasticity to discuss optimum structure. Experiment used a model of the automobile hub made from epoxy resin, assumption parts of a bearing and brake plate. In the experiment, load to the automobile hub were increased by the assumption parts of the bearing and some weights. Stress distribution showed that stress concentration by the cornering force became remarkable at 3 points. One was fillet in boss root, the others were bolt hole and contact department with the brake plate. On the other hand, principal stress chart showed that 3 singular points appeared near the bolt hole and the fillet in the automobile hub. At least, singular point of near the fillet was divergent type from an accident example which had occurred in 2002. At results, designing optimum automobile hub needs to discuss structure of the 3 points.

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Infrared thermography equipped with an infrared array sensor was developed, and the performance of the infrared thermography improved greatly. We are able to measure a difficult non-steady temperature change. By utilizing active thermography method of giving an intentional temperature change, it is applied to a stress measurement, and a non-destructive diagnostic. JFE Steel has developed a remote inspection technology of fatigue cracks in steel structure using infrared-thermography. In this report, we report a principle of the heat elasticity heat generation method, a laboratory examination result and an actual machine test result.

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The final aim of this study is to come up with a new method which supersedes conventional means. It should be superior and can be used flexibly for visualization of strain, comparing to the previous ones. Therefore, we attempted to visualize the strain by using three various types of films, which are piezoelectric film (PVDF), polyimide film (PI) and temperature-sensitive liquid crystal micro capsule film (TLCM). The PVDF can output strong voltage for repeated load. The PI generates heat in regarded to the voltage. And then, TCLM can recognize the heat visually. The PVDF is to the PI what demand is to supply. The TCLM is used so as to visualize the thermal field of the PI. Finally, we acquired valid consequences by the way of complex the above films through experiments, so that we'd like to address regarding this study

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This study examined a method on non-destructive detection of the strain of SUS304 and SUS316, which are austenite stainless steel. Eddy current method was employed to detect strain. Four specimens were prepared for SUS304 and SUS316 respectively. The plastic strain of 1, 5, 10, and 16% were applied to the specimens by using a tensile testing equipment. The eddy current signals on the center of the specimens were measured with an eddy current flaw detector. The eddy current signals were determined by difference on the detector output of the specimen without strain and the strain applied specimen. Specimen without strain and the strain applied specimen. Specimen with larger plastic strain showed larger eddy current signals. SUS316 indicated smaller value on the eddy current signal than that of SUS304. Eddy current signals and plastic strain of the specimens showed a linear relation. The relation can be used to estimate the plastic strain by eddy current signal.

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The aim of this work is to show nucleation and development of creep voids under multi-axial stresses. Type-IV creep damage has been a troublesome problem formed in a fine-grained heat effected zone (HAZ), and it resulted in the degradation of the creep strength of structural components. The stress condition in the fine grained HAZ is usually under multi-axial stress state because the HAZ is bound by the base and the weld metals. In this study, some interrupted creep tests were performed employing circumferentially notched bar specimens of pure aluminum to examine the relation between nucleation/development of creep voids and multi-axial stress field. Distributions of creep voids were measured and counted the number and the damage ratio after segmentalizing metallographs. The photographs were divided by some types of grid lines at counting these damage, and evaluated by a similar A-parameter method. Experimental results showed that creep voids were formed in notch root inclined from the loading axis by about 45 degrees. Elastic creep FE analyses were performed to calculate the change of triaxial factor A in the notch root during creep. The triaxial factor A and the distribution of voids were almost the same trend in the distribution of voids.

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Most of boiler component structures are mainly fabricated by welding which are likely to be regions of crack initiation and propagation. However, the technique of predicting the life of creep crack initiation and growth have not been clearly developed for weldments of W-added 9 %Cr ferritic heat-resistant material (ASME Code Case 2179, ASTM A335 P92) due to many factors such as the variation in micro-structure and the residual stress caused by welding and thermal cycles. In the present paper, high temperature creep crack growth tests were conducted using C(T) specimens and circular notched specimens with the cracks in the heat affected zone of weldments for P92. To derive the algorithm of predicting the life of creep crack growth for weldments, the creep crack growth rate were estimated by C*, d&dt and Q* parameters.

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Testing method under the creep-fatigue conditions has been proposed as the ASTM standard E2714-09. In accordance with the ASTM standard, round bar smooth specimen have been recommended as a testing specimen. Additionally, creep-fatigue crack initiation and growth life are usually defined as the attainment of a specific rate of decrease in the maximum tensile stress or the modulus of elasticity ratios. However, these criterions of crack initiation and growth life on ASTM standard are not characterized from a mechanical view point. In this study, the creep-fatigue crack initiation and growth tests for P92 were conducted using circular notched round bar specimens under strain controlled conditions. An attempt is made to measure the crack length during the tests by DCPD method, which results in the establishment of high accuracy crack length measurement. Additionally, the criterions of crack initiation and growth life under the creep-fatigue interaction conditions were discussed.

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Machine structure under elevated temperature generally causes not only static stress but multiaxial cyclic stress. It is common to be subjected cyclic stress simultaneously with mean stress. It is necessary to accumulate not only experimental data, such as creep and fatigue, but also the experiment data of fatigue-creep interaction in designing these structures. However, there are very little studies of inelastic deformation under multiaxial cyclic stresses. The purposes of this research are to obtain of the experimental data with reliability under multiaxial cyclic stresses, and to construct of the constitutive equation. It carried out a tension - torsion cyclic tests using triangular stress wave and the tension-torsion cyclic experimental result was compared with analysis result on three stress conditions at 260 °C. As the result, it was found that the constitutive equation tended to underestimate the cycle.

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When evaluating the durability of engine parts, it is important to know the internal residual stresses that cause crack growth and influence fatigue strength. The only way to measure internal stresses nondestructively is by the neutron diffraction. However, it is difficult to apply this method to aluminum alloy castings with coarse crystal grains because there are few grains contributing to intensity of diffraction in gauge volumes. In this study, the applicability of "the oscillation method" to aluminum alloy castings was investigated with the aims of solving the problem and establishing a method of measuring internal stresses and strains of this material. Specimens made of an aluminum alloy casting were subjected to a bending load and a neutron diffraction experiment with oscillations was conducted. The experimental results show that an oscillation range of ±15 degrees provides enough intensity of diffraction to read peak positions. Under this condition, the differences between the strain values obtained by diffraction and with strain gauges were less than 250 X 10-6 and the accuracy of the stresses was within 20-25 MPa. We also applied this condition to actual cylinder heads. It was found that there were internal tensile residual stresses in regions where cracks grow easily. We verified the efficacy of the oscillation method for aluminum alloy castings.

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Residual stress distribution in thermally grown oxide (TGO) layer of thermal barrier coatings (TBCs) was measured by using Raman spectroscope. The residual stress in TGO near bond coat was higher than that near top coat, but the difference decreased with an increase in number of thermal cycles. Although the thickness of TGO and Al element amount in TGO increased with an increase in number of thermal cycles, the average residual stress in TGO decreased.

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The purpose of this study was to understand the effect of spraying method on residual stress in thermally grown oxide (TGO) on NiCrA1Y coating. NiCrAlY alloy coat was sprayed by Air plasma spraying (APS) and high velocity oxygen-fuel spraying (HVOF), respectively, on a nickel based superalloy. The microstructure of NiCrAIY coating layer was observed by using scanning electron microscope (SEM). The element distribution of NiCrAlY coating layer was investigated by using electron probe micro analyzer (EPMA). The residual stress in TGO was measured by photo luminescence piezo-spectroscopy (PLPS), which increased with an increase in thermal exposure time. The residual stress of APS coating at 1000°C was higher than that of HVOF coating. However, residual stress of the APS coating at 1100°C was almost the same as that of HVOF coating.

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Three-dimensional distribution of weld residual stress in a large-bore and heavy-walled stainless pipe with butt-welded joint was evaluated by inherent strain method with distribution function. The weld joint was made by TIG welding with single-U shape groove and its size is used in the primary coolant system in nuclear power facilities. The residual stress distribution in the circumferential direction as well as in the through-thickness direction of the joint was estimated using the measurement values obtained in the multiple positions. It was clarified that the three-dimensional stress distribution in the weld end was different from that in the other region.

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This paper deals with the tensile forces acting on the three slender rigid inclusions in an infinite elastic plate under tensions. A method of fundamental solution is presented for the problem by using the Kelvin's solution in the two dimensional theory of elasticity. A principle of the method of solution is to distribute body forces so as to satisfy boundary conditions of the problem. Influences of the length and the distances between the three inclusions on the tensile forces are investigated by numerical calculations and compared with the results for the case of two slender inclusions.

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