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64.
A neon circuit which consists of nonvolatile metal-ferroelectric-semiconductor field effect transistors (MFSFETs) and a uni-junction transistor (UJT) has been proposed. In the proposed circuit MFSFETs act as analog memories to store the synaptic weights which can be changed by the adaptive-learning process during the operations. In this paper, we first simulate the operation of the ferroelectric neuron circuit using a circuit simulator, SPICE. It is shown that the output frequency of the proposed neuron circuit can be changed after it processes a certain number of input pulses. Then, we report the fabrication of UJTs and UJT pulse oscillation circuits using silicon-on-insulator (SOI) substrates. It is found that the output frequency increases with decreasing the charging time of the capacitor in the circuit and that the operation at higher frequencies is possible for integrated UJT oscillation circuits. Finally, we demonstrate the memory and learning properties of n-channel ferroelectric-gate FETs using (Pb,La)(Zr,Ti)O3 (PLZT) films. It is shown that the drain current of the PLZT/SrTiO3/Si FETs can be controlled by a “write” pulse before the measurements.  相似文献   
65.
Japan was defeated in World War II and almost all of the nation was demoralized by the destruction and damage to much of the nation. The medical and health care system during and before World War II needed to be reformed radically and fundamentally since almost all medical and health institutes were destroyed. On the other hand, many health personnel came back from overseas after the war. Japanese modern medicine had developed on the basis of German medicine; however, many aspects of American medicine, including public health and democracy, were rapidly introduced following the end of World War II. The American type of health center was established and many laws concerning medical and health care were enacted in 1947-1948. One of them was "The Health Center Law." The National Health Insurance Act was enacted in 1958 and the total population has been covered by health insurance plans since 1961. Many physicians quit the health centers and they have worked as clinicians under the National Health Insurance scheme, because health centers were introduced before adequate education and research existed in the field of public health. On the other hand, the health insurance scheme was in its golden age during the high economic growth period of the 1960s. Japan has succeeded in all forms of modern technology and economy for the past 30 years and is now one of the top nations in the field of medical and health care, such as the numbers of clinics and hospitals and beds, the frequency of consulting with a doctor, length of hospital stay, examinee rates in mass health examinations in the community and workplace and so on. Health conditions have changed drastically from the 1950s to the present. Therefore, health centers do not fit current health needs. For example, mortality from tuberculosis, acute infections diseases and also stomach and uterus cancers and apoplexy have decreased rapidly while mortality from chronic diseases, especially lung, breast and rectal cancers, and myocardial infarction have increased gradually. Changes of life style resulting from rapid economic growth are suspected to be important causes of the change in the prevalence of these diseases. Mass health examination was important and effective as a preventive measure against tuberculosis, especially as a means of early detection and early treatment. However, it is not now effective against chronic diseases. The screening examination has resulted in identifying many patients suspected of being ill. Every examiner must be able to distinguish pathologic findings from physiologic changes of aging. Every patient must, therefore, understand his/her individuality and evaluate the result of his/her efforts to improve life style by receiving a health examination. Accordingly, the aim of health examination has changed from early detection to health support for the examinee. During the decades when life expectancy was less than 50 years of age, it was not necessary for people to plan for retirement. Moreover, there was little burden on younger generations to provide care for the aged people because there were few old people more than 70 years of age and the birth rate was high. Nowadays, elderly people face many years of life after retirement and there are too many aged people in relation to the number of younger persons. As for medical care services, many new medical needs have emerged in recent years, including "quality of life," "palliative medicine in terminal care," "establishment of a primary care system" and "comprehensive care connecting health and medical care with welfare" etc. Improved living standards resulting from economic growth, called the "economic miracle" internationally, have helped to bring about a rapid and wide range of change in daily lifestyle, such as eating habits, working conditions and environment. The Ministry of Health and Welfare has made every effort to revise the laws in relation to health and medical care systems, in order to adjust to recent  相似文献   
66.
In this study, we develop a high frame-rate vision system that can execute color histogram-based tracking of multiple color-patterned objects in a 512 × 512 image at 2,000 fps by implementing an expanded cell-based labeling algorithm as the hardware logic. In the hardware implementation of the expanded cell-based labeling algorithm, the 16-bin hue-based color histograms of 1,024 color-patterned objects in an image can be extracted simultaneously by dividing the image into 8 × 8 cells concurrently, after calculating the 0th, 1st, and 2nd moment features to obtain the positions, areas, and orientation angles of multiple objects. We verified the effectiveness of our developed tracking system by performing several experiments using multiple color-patterned objects, which were always tracked even when they moved rapidly with occlusions in the camera views.  相似文献   
67.
The present paper introduces a numerical solution to shape optimization problems of domains in which boundary value problems of partial differential equations are defined. In the present paper, the finite element method using NURBS as basis functions in the Galerkin method is applied to solve the boundary value problems and to solve a reshaping problem generated by the H1 gradient method for shape optimization, which has been developed as a general solution to shape optimization problems. Numerical examples of linear elastic continua illustrate that this solution works as well as using the conventional finite element method.  相似文献   
68.
We look on the cotton fiber reinforced plastics as industrial gear materials, and have been developing design systems for industrial gears made of cotton fiber-reinforced plastics. In this report, we deal with a method estimating for tooth root stresses caused by bending movements under running conditions. The gear material used was cotton fiber plain woven cloth reinforced phenolic resin laminates. Paper-reinforced phenolic resin laminates, a commonly used material, was used as a control for comparison. The main dimensions of the gears were module 3–5 mm and tooth width 25 mm. First, accelerations of gears were measured under running conditions to estimate dynamic performance. Second, fracture tests of gear teeth were carried out under bending loads. Different fracture modes at tooth roots for cotton fiber-reinforced plastics and phenolic resin gears were observed. The fractures occurred at a high position from the tooth root in the case of the cotton fiber-reinforced plastics gear because the cotton fiber-reinforced plastics had excellent cleavage and shear strength. This gear also had higher strength for tooth bending loads. Third, the mechanical properties of the gears were researched by tensile, bending, and shearing tests. It was clear that the cotton fiber-reinforced plastics had excellent properties in cleavage fracture between laminates and shear strength. Finally, we proposed a design method for this gear, which considers the cleavage and shear strength.  相似文献   
69.
In higher plants, glycolipids such as monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG) are major components of chloroplast membranes in leaves. A recent study identified an isoform of MGDG synthase that is expressed specifically in floral organs, suggesting a novel function for glycolipids in flowers. To elucidate the localization and developmental changes of glycolipids and their biosynthetic activities in flowers, we carried out a series of analytical studies with Petunia hybrida. The results showed that the biosynthetic activities of galactolipid synthesis, particularly for DGDG, increased during flower development. Among the floral organs, the pistil had the highest galactolipid synthetic activity. Its specific activity for incorporation of UDP-galactose to yield galactolipids was estimated to be more than twice that of leaves, which are the major site of galactolipid synthesis in plant tissues. Analysis of lipid contents of pistils revealed that they contained higher amounts of galactolipids than other floral organs. Moreover, DGDG was more abundant than MGDG in both pistils and petals. These results show that DGDG is a major glycolipid in floral organs and that DGDG biosynthetic activity is highly upregulated in the pistils and petals of Petunia flowers.  相似文献   
70.
Photografting (λ > 300 nm) of N‐isopropylacrylamide (NIPAAm) and glycidyl methacrylate (GMA) binary monomers (NIPAAm/GMA) on low‐density polyethylene film (thickness = 30 μm) was investigated at 60°C using mixed solvent consisting of water and an organic solvent such as acetone. Xanthone was used as a photoinitiator by coating it on the film surfaces. A maximum percentage of grafting was observed at a certain concentration of acetone in the mixed solvent, which was commonly observed for both ratios of NIPAAm/GMA, 8/2 and 7/3. Based on the photografting of NIPAAm/GMA on xanthone‐coated film, monomer reactivity ratios of NIPAAm (r1) and GMA (r2) were calculated using the Fineman–Ross method. The values were 0.31 ± 0.1 and 4.8 ± 0.2 for the water solvent system, while they were 0.96 ± 0.1 and 4.9 ± 0.1 for the mixed solvent system. NIPAAm/GMA‐grafted films with a homogeneous distribution of grafted chains were formed by photografting using water and mixed solvents. The NIPAAm/GMA‐grafted films exhibited temperature‐responsive characters, whereas the grafted films showed a reversible change in the degree of swelling between 0 and 50°C, respectively. Epoxy groups in the grafted poly(NIPAAm/GMA) chains could be aminated with ethylenediamine in N,N′‐dimethylformamide at 70°C for 3 h. Complexes of the aminated NIPAAm/GMA‐grafted chains with cupric ion exhibited catalytic activity for the decomposition of hydrogen peroxide at 20 to 50°C. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2469–2475, 2005  相似文献   
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