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The present study was aimed to develop a probabilistic finite element method (FEM) that predicts the variability in the fatigue life of additively manufactured clasp so that it can be used as a virtual test in the design phase before manufacturing. Titanium alloy (Ti-6Al-4V) clasp with integrated chucking part, which was designed for experimental fatigue test to validate the computational method, was investigated. To predict the lower bound, an initial spherical defect was assumed in the region where stress concentration was predicted. The Smith-Watson-Topper (SWT) method, BäumelSeeger rule, elasto-plastic FEM, and zooming FEM were used. The influence of assumed initial defect on the fatigue life was significant, and the large variability in the fatigue life was predicted. This study demonstrated that the proposed practical computational method can simulate the large variability in the fatigue life of titanium alloy clasp, which is useful in its design before manufacturing.

Aiming at the future applications of a lattice structure manufactured by selective laser sintering for bone scaffold in the biomedical field, by putting highlight on the possible imperfections influenced by different manufacturing strategies, a numerical prediction method was studied and compared with compressive test results. To consider the geometrical imperfections as well as the uncertainty in sintered material property, the first-order perturbation based stochastic homogenization (FPSH) method was employed. To be able to compare products made by three different printing service companies, maraging steel was used in this study, which was commonly available. Several geometrical imperfections were categorized into kink, notch and hole, and representative dimensions were parameterized and measured statistically using micro-CT images. They were also correlated to the building direction and support types. The numerical prediction revealed the reduction of stiffness in a stochastic way qualitatively. The constructed database of the geometrical imperfections and the FPSH method will be useful in the next occasion of manufacturing unexperienced product.

The deformation behavior of 6000 series aluminum alloy sheets under biaxial tension was precisely measured for linear stress paths, using servo-controlled biaxial tensile tests with both cruciform and tubular specimens. The tubular specimens were fabricated by bending and laser-welding as-received flat sheet materials. Differential work hardening (DWH) behavior was observed; the shapes of the contours of the plastic work constructed in the principal stress space changed with an increase in plastic work. A new constitutive model that can reproduce the DWH behavior was proposed; the model is based on the Yld2000-2d yield function with the exponent and material parameters changing as functions of plastic work. Finite element analysis of hydraulic bulge forming was performed using both the proposed DWH model and the conventional isotropic hardening model based on selected yield functions. The calculated results based on the DWH model were in closest agreement with the experimental results. Thus, the new constitutive model has been verified to be effective for improving the accuracy of the FEA.

A method of evaluating stress measurement errors in biaxial tensile tests using a cruciform specimen is proposed. The cruciform specimen is assumed to be fabricated from a section of uniformly thick flat sheet metal via laser or water-jet cutting and to have a number of parallel slits cut into each of the four arms. Using finite element analyses with the von Mises yield criterion, the optimum geometry of the cruciform specimen and the optimum strain measurement position necessary to minimize the stress measurement error are determined. Additionally, an experimental validation of the FEA is performed using a sheet material that was experimentally confirmed to be nearly isotropic. The following conclusions are drawn: (i) the thickness of the test material should be less than 0.08B (B: side length of the gauge area of the cruciform specimen); (ii) the geometric parameters for the cruciform specimen should be N ≥ 7 , L ≥ B , w s ≤ 0.01 B , and 0 .0034 ≤ R / B ≤ 0.1 (N: number of slits, L: length of slits cut into the arms, w s : slit width, and R: corner radius at the junction of the arms to the gauge area); and (iii) the strain components in the gauge area should be measured on the centerline of the specimen parallel to the maximum force direction at a distance of approximately 0.35B from the center of the specimen. The stress measurement error is estimated to be less than 2% when the optimum conditions above are satisfied.

Numerous types of yield functions have been proposed to describe the shape of a realistic yield surface. Major commercial finite element codes include few anisotropic functions. Alternatively, the codes allow for user-subroutines that enable users to implement material models. The Unified Material Model Driver for Plasticity (UMMDp) subroutine library, which enables users to implement an arbitrary yield function easily, is developed. The framework of the UMMDp and examples of sheet metal forming analysis are presented.

To implement new yield functions into the user subroutines of advanced FE codes, professional skills and knowledge are required. The Japan Association for Nonlinear Computer Aided Engineering (JANCAE) has been acting as an organization that provides information and knowledge on finite element analysis (FEA) to the researchers and engineers in various positions involved in CAE. Since 2009, as one of the subcommittee activities for applying FEA to practical metal-forming problems, we have not only studied elastoplastic theory, but have also developed the Unified Material Model Driver for Plasticity (UMMDp), a user subroutine library. Basic yield functions, such as the von Mises and Hill's quadratic yield functions, which almost all advanced FE code already has, were implemented in the UMMDp as a basic study at its beginning of the development. Up to now, many anisotropic yield functions, including Yoshida's 6th-order polynomial, Barlat's Yld2000 and Yld2004, Comsa and Banabic's BBC2008, Cazacu's CPB2006, and Vegter's spline yield functions, have been implemented in the UMMDp, and it is possible to add a new yield function. In this presentation, the techniques for implementing yield functions in the UMMDp are explained. Moreover, the problem of BM1 in NUMISHEET 2016 is discussed as an example applying selected yield functions to the implementation procedure.

Many yield functions have been proposed in academia to describe the complicated shapes of yield surfaces of metals. However, many of the commercial FEM codes provide only classical yield functions. Moreover, it takes a long time for engineers to implement newly proposed yield functions to commercial FEM codes. The Japan Association for Nonlinear CAE (JANCAE), a non-profit organization, developed the Unified Material Model Driver for plasticity (UMMDp) subroutine suite with the cooperation of industry users of CAE and the engineers of software venders. This subroutine provides several anisotropic yield functions, and is applicable to most of the commercial FEM codes. The users can implement their own anisotropic yield functions easily using the UMMDp. This paper presents the basic framework of UMMDp and the development activities performed with many volunteers.

The accuracy of cup drawing simulation of aluminum alloy sheets strongly depends on the hardening and yield functions used in the simulation. In this study, stress-strain curves for an AA3104 aluminum alloy sheet were measured by uniaxial tensile and rolling tensile tests to identify parameters for various hardening functions. In addition, in-plane uniaxial tensile, biaxial tensile, and combined tension-compression tests were carried out to measure the successive contours of plastic work in the stress space and the directions of plastic strain rates under linear stress paths. The anisotropic coefficients, α 1-α 8, and exponent M of the Yld2000-2d yield function were determined so that the mean square error of the analytical yield locus from the measured plastic work contour was minimized. Finite element simulations of cup drawing of the aluminum alloy sheet were carried out using the determined parameters for hardening functions and the Yld2000-2d yield function implemented in LS-DYNA. By comparing the simulation results with the results of cup drawing experiments, the effects of the hardening functions on the accuracy of earing profile prediction were investigated.

Anisotropy in deformation and fracture strength of an aluminum beverage can body is investigated using a servo-controlled tension-internal pressure testing machine. The yield surface and forming limit strain and stress diagrams of the can body are successfully determined using linear strain-path tests. We conclude as follows:(i)The initial yield surface of the can body is in good agreement with Yld2000-2d yield criterion with degree of 10;(ii)fracture always occurs at θ=0° under linear strain-paths with eθ/eφ>1, where θ is the circumferential position on the can body measured from the rolling direction of the blank sheet, and eθ and eφ are circumferential and axial strain components, respectively. We found that eθ is significantly lower at θ=45° than at θ=0° and 90°;(iii)The fracture strength of the can body under plane-strain tension with eφ=0 is minimum at θ=0°and maximum at θ=45°; this accords with the result of(ii);(iv)In order to evaluate the fracture strength of the can body accurately, the stress state of the can body in the test should be as close as possible to the one that occurs in a can body in a real service condition.

Spectroscopic reflectometry is a nondestructive technique widely used to analyze the properties of materials as thin layer thicknesses are used in advanced packaging manufacturing. The technique is based on the propagation of waves into media. If a discontinuity is encountered, a part of its energy is reflected back to the injection point according to the well-known law of reflection. The reflected signal gives useful information about the system and, in particular, thicknesses of thin layers.

As 3DIC with through silicon vias (TSV) approaches high volume manufacturing readiness the importance of precision backgrinding has become increasingly more evident. Active management of the backgrinding process has multiple benefits in that it reduces the risk of wafer backside contamination due to premature contact with vias, it enables optimization of the post-thinning residual silicon thickness and the final via reveal process. It can compensate for poor via fabrication depth uniformity and less than ideal temporary bonding total thickness variation (TTV). In this paper we will demonstrate the utility of two tools that when used together can systematically produce thin TSV containing wafers to their optimal thickness while protecting the wafers from particulate contamination. The first instrument in this process scheme is a metrology tool that utilizes IR reflectance to measure the silicon thickness remaining between the bottom of the TSV and backside surface of the wafer. These measurements are then transferred to a special grinding tool that can interpret the data and make changes to the grinding depth within the wafer so as to leave thickness of silicon above the TSVs as uniform as possible. Having removed the bulk of the Si through mechanical grinding and Chem/Mech polishing, the next step in the via-middle process is to remove the last few microns of Si overburden to expose the vias. By leaving a shallower Si layer above the TSV during the thinning process compared to current process, the final via reveal process time can be reduced. Also the need for rework in this process because of the wafer-to-wafer variability in the remaining silicon thickness above the TSV can be eliminated. In addition to measuring the pre-grinding Si thickness, the IR reflectance measurement tool can be used to verify the remaining silicon thickness post grind, establishing thinning process feedback and via reveal process feed-forward data.

N2/Ar and He/Ar ratios and their isotopic ratios of gas samples from exploration and production wells of oils and natural gases in the Tohoku district, Japan, were measured for discussing the origins of natural gases. Their plots of N2/Ar and He/Ar ratios from the Green Tuff region and non-volcanic area show the common distribution with positive correlation, being lower than those of geothermal and volcanic gases which contain the magmatic gas with higher N2/Ar and He/Ar ratios in the Northeast Japan. In their distribution zone, the gases collected from formations with high maturity level of organic matter show high N2/Ar and He/Ar ratios, while the gases from the formations with its low maturity level give their low ratios. The natural gases of their high ratios contain thermogenic CH4 and N2 accompanied by Ar having high 40Ar/36Ar ratios deep-seated in the crust. On the other hand, the gases with low N2/Ar and He/Ar ratios are characterized mainly by biogenic CH4 and atmospheric N2 and Ar with low 40Ar/36Ar ratios. These results indicate that natural gases from the Green Tuff formations rarely contain magmatic N2 and CH4. Furthermore, the correlation between N2/Ar and He/Ar ratios of natural gases seems to be useful in estimating their origins and the environment of their generations.

In order to know leprosy chemotherapy status in Japan, three recently conducted Government-supported nation-wide survey, namely chemotherapy research group survey (Takizawa, 1994, 71 cases) follow up result of Takizawa's study (Miyagi, 1997, 59 cases) and leprosy patient registry (Goto, 1996, 130 cases) were compared and analyzed. For most fresh and relapse cases, multi-drug therapy were applied, among them rifampicin/dapsone or rifampicin/dapsone/clofazimine combinations were selected in about half of new cases and about 1/3 of relapse cases. In many cases dose and intervals were based on WHO protocol, however smaller dosage was used in some cases. Quinolone (ofloxacin) was used in 40% of cases during the therapy. Reversal reaction was observed in 7/71 cases and erythema nodosum leprosum was observed in 6/71 cases. In order to prevent chemotherapy-induced deformities, we propose a modified protocol for new cases accompanied by reactional status, which starts with clofazimine monotherapy and followed by WHO/MB.

Numerous types of yield functions have been proposed to describe the shape of a realistic yield surface. Major commercial finite element codes include few anisotropic functions. Alternatively, the codes allow users to implement material models through user- subroutines. We develop the Unified Material Model Driver for Plasticity (UMMDp) subroutine library, which enables users to implement an arbitrary yield function easily. In this paper, the framework of the UMMDp is presented and its availabilities is shown through examples of sheet metal forming analyses.

In-plane biaxial tension and combined tension-compression tests are carried out for AA3104 aluminum alloy sheets. Linear stress paths are applied to cruciform specimens to measure the contours of plastic work in the stress space and the directions of plastic strain rates at each stress path. Coefficients α 1- α 8 and exponent M of the Yld2000-2d yield function are determined to minimize the mean square error of the analytical yield locus from a measured work contour. The values of the weighting coefficients in the evaluation of the error are varied to check the effect of a specific stress state on the earing behavior. The effects of the combinations of the weighting coefficients on the accuracy of earing prediction in the cup drawing process are discussed.

A survey of dermatophytes isolated from patients was made from May, 1991 to June, 1992 in Amami-Oshima. One hundred and ninety-one isolates were obtained from 321 cases consisting of tinea capitis 7 (2.2%), tinea corporis 86 (26.8%), tinea cruris 63 (19.6%), tinea pedis 140 (43.6%), tinea manuum 4 (1.2%) and tinea unguium 21 (6.5%). The isolates were 152 (79.6%) of Trichophyton rubrum, 16 (8.4%) of T. mentagrophytes, 3 (1.6%) of T. violaceum, 3 (1.6%) of Trichophyton spp., 14 (7.3%) of Microsporum canis and 3 (1.6%) of M. gypseum. Out of 152 T. rubrum isolates, 104 were granular or powdery, and urease-positive. The dermatophyte flora in Amami-Oshima was intermediate between those in Kyushu and Okinawa.

A new direct Phase-shift/Transmittance measurement tool "MPM193EX" has been developed to respond to the growing demand for higher precision measurements of finer patterns in ArF Lithography. Specifications of MPM193EX are listed below along with corresponding specifications of the conventional tool MPM193. 1) Phase-shift [3 Sigma]: 0.5 deg. (MPM193) => 0.2 deg. (MPM193EX) 2) Transmittance [3 Sigma]: 0.20 % (MPM193) => 0.04 % (MPM193EX) 3) Minimum measurement pattern width: 7.5 μm (MPM193) => 1.0 μm (MPM193EX) Furthermore, new design optics using an ArF Laser and an objective lens with long working distance allows measurements of masks with pellicles. The new method for improving the measurement repeatability is based on elimination of influence from instantaneous fluctuation in interferometer fringes by scanning two adjacent areas simultaneously. Also, MPM193EX is equipped with high-resolution and stable optics. The newly employed auto-focus system in MPM193EX accurately adjusts, by a new image processing method using high-resolution optics, the focus height that is one of the most important factors for measurements in a micro pattern.

National sanatoria for Hansen's disease in Japan were special institutions that only treated in-patients.But a few sanatoria for Hansen's disease located in islands and rural districts should have other duty, namely service to community health because there was no other clinic office.New patients with Hansen's disease are very small in number and inpatients become older and older. Then the new role should be seeked to National sanatoria for Hansen's diaease in Japan. Amami-wakoen, National sanatoium for Hansen's disease in Amami island started skin clinic for out -patients with skin diseases in March, 1983 because there were few skin clinics in Amami district. The number of patients with skin diseases increases year by year (from 12.3 persons every day in 1983 to 36.4 in 1989).We surveyed receipts of Naional health insurance for the purpose of studying the main diseases in Amami main island and the behavior of the patients with skin diseases.The results of survey are followings; 1. The percentage of patients with skin diseases in Amami main island in August, 1987 was significantly superior. 2. The percentage of patients with mental diseases and pregnant woman in hospital and patients with gastrointestinal disorders and pregnant women in clinic were significantly large in May, 1987 in Amami main island. 3. There was a tendency that the patients with skin diseases visited to the clinic near in place. It was found that we treated only 5.1 percent persons of patients with skin diseases in August, 1987.

Mask inspection plays a pivotal role in current high grade mask making processes and further its importance is getting bigger. The purpose of inspection process is as follows. One is simple sorting of NG masks that have fatal defects with high sensitivity. The other is improvement of total mask manufacturing process and mask quality using defect source analysis. As semiconductor device is getting shrunk down, the influence of mask defect is increasing. Therefore, there are special needs for the efficient use of such expensive inspection machines and the systematic approach of defect analysis. In this paper, we propose novel mask inspection flow to improve mask inspection capacity and systematic defect management. In general, Inspection process is divided by two steps. One is detection of defects and the other is review for defect analysis. Our concept of new inspection flow is adoption of individual defect review system after defect detection in inspection machine. With this new inspection flow using defect review system, we could increase inspection capacity by 30% and set up unified defect analysis hub.

Continuous improvements of properties for individual parts are indispensable for perpetual development of aircraft engines. Concerning casing and seal, simulation of ring rolling process is one of the most attractive tools to reduce the cost and time and to improve the properties and the reliability at the same time. In order to obtain both practical prediction accuracy and acceptable computation time from industrial standpoint, the refined partial three-dimensional deformation model was proposed. Moreover the relationship between microstructure evolution and various parameters regarding to Waspaloy* was evaluated and microstructure prediction models were developed. Constructed microstructure prediction models were coupled to the finite element analyzing system to estimate mean grain diameter and fraction of recrystallization in addition to general output e.g. temperature, strain. The effectiveness of proposed prediction system as a process design tool was confirmed through multi compression test and production of actual casing that had extremely complicated near-net-shape.

The performance of an i-/g-line direct-phase measurement system Lasertec MPM- 100 has been evaluated. The minimum measurable pattern sizes is 2.5 .μm for holes on an 8%-i-line transmittance halftone phase shift masks (HPSMs). The effect of the focus position is not significant for hole pattern of above 3.5 μm. Both short-term repeatability and long-term stability are excellent, being less than 0.5 deg. The effect of the illumination NA has been investigated theoretically and experimentally, and the use of correction factors based on experiment is proposed for estimating effective phase shifts from phase shifts obtained by MPM- 100.