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21.
We present a novel scheme of visible gray-image morphology with the visual-area-coding technique (VACT). The VACT is a technique of digitized analog-optical computing in which data are converted into visible coded patterns and processed with the visible form. Because the achievable operations in the VACT are identical to those of mathematical morphology, mathematical morphology is adapted to gray-image morphology with the VACT. Computer simulation and optical experiments of the several operations in mathematical morphology verify the correctness of the proposed technique. The processing capacity of the proposed method is estimated in terms of the space-bandwidth product. 相似文献
22.
T Yamagata J Nishida S Tanaka R Sakai K Mitani M Yoshida T Taniguchi Y Yazaki H Hirai 《Canadian Metallurgical Quarterly》1996,16(4):1283-1294
We have isolated a novel cDNA clone encoding interferon (IFN) consensus sequence-binding protein in adult T-cell leukemia cell line or activated T cells (ICSAT); this protein is the human homolog of the recently cloned Pip/LSIRF. ICSAT is structurally most closely related to the previously cloned ICSBP, a member of the IFN regulatory factor (IRF) family of proteins that binds to interferon consensus sequences (ICSs) found in many promoters of the IFN-regulated genes. Among T-cell lines investigated, ICSAT was abundantly expressed in human T-cell leukemia virus type 1 (HTLV-1)-infected T cells. When the HTLV-1 tax gene was expressed or phorbol myristake acetate-A23187 stimulation was used, ICSAT expression was induced in Jurkat cells which otherwise do not express ICSAT. When the binding of ICSAT to four different ICSs was tested, the relative differences in binding affinities for those ICSs were determined. To study the functional role of ICSAT, we performed cotransfection experiments with the human embryonal carcinoma cell line N-Tera2. ICSAT was demonstrated to possess repressive function over the gene activation induced by IFN stimulation or by IRF-1 cotransfection. Such repressive function is similar to that seen in IRF-2 or ICSBP. However, we have found that ICSAT has a different repressive effect from that of IRF-2 or ICSBP in some IFN-responsive reporter constructs. These results suggest that a novel mechanism of gene regulation by "differential repression" is used by multiple members of repressor proteins with different repressive effects on the IFN-responsive genes. 相似文献
23.
Hiroki Yamaguchi Tsuneo Hanawa Oto Yamamoto Yu Matsuda Yasuhiro Egami Tomohide Niimi 《Microfluidics and nanofluidics》2011,11(1):57-64
The tangential momentum accommodation coefficient (TMAC) was investigated experimentally from the mass flow rate through a
single microtube under the slip flow and the early part of the transition regime. The measurements were carried out by the
constant-volume method under the mean Knudsen number smaller than 0.3, which is based on the mean pressure of the inlet and
the outlet of the microtube, to apply the second-order slip boundary condition. To measure TMACs on various materials, quite
large microtube was employed, which require the reduction in leakage. TMAC was obtained from the slip coefficient determined
by the relation of the mass flow rate to the mean Knudsen number. The obtained mass flow rate was well explained by the theoretical
equation. TMACs of deactivated-fused silica with argon, nitrogen, and oxygen were measured, showing the tangential momentum
was not accommodated completely to the surface, and the values showed good agreement with previous studies. From the comparison
between microtubes with different inner diameter, it is showed that TMAC is determined mainly by gas species and surface material. 相似文献
24.
Yusuke Fukui Yosuke Honda Yasuhiro Yamauchi Michiko Okafuji Masahiro Sakai Mikihiko Nishitani Yusuke Takata 《Journal of the Society for Information Display》2010,18(12):1090-1094
Abstract— MgO thin film is currently used as a surface protective layer for dielectric materials because MgO has a high resistance during ion sputtering and exhibits effective secondary electron emission. The secondary‐electron‐emission coefficient γ of MgO is high for Ne ions; however, it is low for Xe ions. The Xe content of the discharge gas of PDPs needs to be raised in order to increase the luminous efficiency. Thus, the development of high‐γ materials replacing MgO is required. The discharge properties and chemical surface stability of SrO containing Zr (SrZrO) as the candidate high‐γ protective layer for noble PDPs have been characterized. SrZrO films have superior chemical stability, especially the resistance to carbonation because of the existence of a few adsorption sites due to their amorphous structure. The firing voltage is 60 V lower than that of MgO films for a discharge gas of Ne/Xe = 85/15 at 60 kPa. 相似文献
25.
重复控制系统中非周期扰动的抑制 总被引:3,自引:0,他引:3
为了改善重复控制系统中的扰动抑制性能,提出一种基于曲率模型的扰动估计新方法.该方法的主要特点是扰动的估计值直接与重复控制规则结合也不影响重复控制系统的稳定性.仿真结果显示该方法可以有效地抑制扰动. 相似文献
26.
Yasuhiro Kodera Takeshi Yamamoto Naoki Toyofuku Manshi Ohyanagi Zuhair A. Munir 《Journal of Materials Science》2006,41(3):727-732
The ordering of stacking-disordered silicon carbide prepared from the elements by high energy ball milling was investigated
during sintering. A sharp increase in density in the temperature region 1700–1800°C was associated with a decrease in the
disorder. Samples which had low disorder density showed a more continuous sintering behavior with temperature. Highly dense
(up to 99% relative density) SiC can be obtained at 1900°C under a pressure of 70 MPa with no hold time. Similar results were
observed for structurally disordered carbon with 10 at% of boron. The sintering behavior exhibited an abrupt density increase
in the narrow temperature region of 1450–1600°C and was associated with disorder-order transformation. 相似文献
27.
Noriaki Murakami Koji Arafune Tadanobu Koyama Yoshimi Momose Tetsuo Ozawa Yasunori Okano Sadik Dost Le. H. Dao Masashi Kumagawa Yasuhiro Hayakawa 《Microgravity science and technology》2005,16(1-4):79-83
The effect of gravity on dissolution of GaSb in InSb melt and growth of InGaSb was experimentally investigated. Experiments were carried out in a GaSb(seed)/InSb/GaSb(feed) sandwich system under an imposed temperature gradient. In the experiments, the GaSb feed crystal dissolved into the InSb melt to supply the required GaSb component for the growth of In0.1Ga0.9Sb crystal. Two parameters were considered: (1) the inclination angle (θ) of the sample for gravity as 0° and 53°, and (2) the sample diameter (D) as 9 mm and 5mm. When θ was 0°, the interface was almost flat, indicating that convection was axisymmetric and stable. Whereas the interface was distorted towards gravitational direction when θ was 53°, indicating that solutal convection was dominant. The decrease of growth temperature and sample diameter reduced the distortion of interface and the dissolution amount of GaSb feed. The homogeneous crystals were grown at the initial growth stage by supplying the GaSb component during growth. 相似文献
28.
In order to non-destructively evaluate changes in toughness of cast duplex stainless steel, which is frequently used in main coolant pipes of PWR type nuclear power plants, due to thermal aging, we tried to apply thermoelectric power (TEP) measurement. because TEP is sensitive to microstructural material changes, and to clarify the mechanism behind TEP changes due to thermal aging. As a result, TEP of cast duplex stainless steel increased with aging time, and good correlations were found between TEP and toughness. Concerning the mechanism, TEP of high and low Cr content alloys was higher than that of intermediate Cr content alloys. Because high and low Cr areas are created in the ferrite phase due to thermal aging. TEP of the entire material increased. Furthermore, when each Cr fluctuating area acted in parallel, the increase in TEP became larger. According to the Mott-Jones theory, TEP is largely related to the electron density of states at the Fermi level. The electron density of states of Fe–Cr–Ni alloys in the valence band was measured with X-ray photoelectron spectroscopy (XPS). As a result, there was a high correlation between the TEP calculated from the XPS spectrum and the measured TEP. Therefore, we showed experimentally that the electron density of states changed due to variations in Cr concentration, which also affect TEP. 相似文献
29.
Hidemi Yamachi Yasuhiro Tsujimura Yasushi Kambayashi Hisashi Yamamoto 《Reliability Engineering & System Safety》2006,91(9):1083-1094
N-version programming (NVP) is a programming approach for constructing fault tolerant software systems. Generally, an optimization model utilized in NVP selects the optimal set of versions for each module to maximize the system reliability and to constrain the total cost to remain within a given budget. In such a model, while the number of versions included in the obtained solution is generally reduced, the budget restriction may be so rigid that it may fail to find the optimal solution. In order to ameliorate this problem, this paper proposes a novel bi-objective optimization model that maximizes the system reliability and minimizes the system total cost for designing N-version software systems. When solving multi-objective optimization problem, it is crucial to find Pareto solutions. It is, however, not easy to obtain them. In this paper, we propose a novel bi-objective optimization model that obtains many Pareto solutions efficiently.We formulate the optimal design problem of NVP as a bi-objective 0–1 nonlinear integer programming problem. In order to overcome this problem, we propose a Multi-objective genetic algorithm (MOGA), which is a powerful, though time-consuming, method to solve multi-objective optimization problems. When implementing genetic algorithm (GA), the use of an appropriate genetic representation scheme is one of the most important issues to obtain good performance. We employ random-key representation in our MOGA to find many Pareto solutions spaced as evenly as possible along the Pareto frontier. To pursue improve further performance, we introduce elitism, the Pareto-insertion and the Pareto-deletion operations based on distance between Pareto solutions in the selection process.The proposed MOGA obtains many Pareto solutions along the Pareto frontier evenly. The user of the MOGA can select the best compromise solution among the candidates by controlling the balance between the system reliability and the total cost. 相似文献
30.
Atsushi Kanamori Fumio Tanaka Masaki Ominami Yuji Nadatani Shusei Fukunaga Koji Otani Shuhei Hosomi Noriko Kamata Yasuaki Nagami Koichi Taira Yasuhiro Fujiwara 《International journal of molecular sciences》2022,23(15)
The effects of psychological stress on eosinophilic gastrointestinal disorders have not been elucidated. This study investigated the effects of psychological stress in a mouse model of eosinophilic enteritis (EoN). BALB/c mice were treated with ovalbumin (OVA) to create an EoN model and subjected to either water avoidance stress (WAS) or sham stress (SS). Microscopic inflammation, eosinophil and mast cell counts, mRNA expression, and protein levels of type 2 helper T cell (Th2) cytokines in the ileum were compared between groups. We evaluated ex vivo intestinal permeability using an Ussing chamber. A corticotropin-releasing hormone type 1 receptor (CRH-R1) antagonist was administered before WAS, and its effects were analyzed. WAS significantly increased diarrhea occurrence and, eosinophil and mast cell counts, and decreased the villus/crypt ratio compared to those in the SS group. The mRNA expression of CRH, interleukin IL-4, IL-5, IL-13, eotaxin-1, and mast cell tryptase β2 significantly increased, and the protein levels of IL-5, IL-13, and OVA-specific immunoglobulin E (IgE) also significantly increased in the WAS group. Moreover, WAS significantly increased the intestinal permeability. The CRH-R1 antagonist significantly inhibited all changes induced by WAS. Psychological stress exacerbated ileal inflammation via the CRH-mast cell axis in an EoN mouse model. 相似文献