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排序方式: 共有4087条查询结果,搜索用时 31 毫秒
101.
This paper deals with the frame topology optimization under the frequency constraint and proposes an algorithm that solves a sequence of relaxation problems to obtain a local optimal solution with high quality. It is known that an optimal solution of this problem often has multiple eigenvalues and the feasible set is disconnected. Due to these two difficulties, conventional nonlinear programming approaches often converge to a local optimal solution that is unacceptable from a practical point of view. In this paper, we formulate the frequency constraint as a positive semidefinite constraint of a certain symmetric matrix, and then relax this constraint to make the feasible set connected. The proposed algorithm solves a sequence of the relaxation problems with gradually decreasing the relaxation parameter. The positive semidefinite constraint is treated with the logarithmic barrier function and, hence, the algorithm finds no difficulty in multiple eigenvalues of a solution. Numerical experiments show that global optimal solutions, or at least local optimal solutions with high qualities, can be obtained with the proposed algorithm. 相似文献
102.
103.
Mishra JS Sakamoto R Motojima G Matsuyama A Yamada H 《The Review of scientific instruments》2011,82(2):023505
A low speed single barrel pellet injector, using a mechanical punch device has been developed for alternative injection in the large helical device. A pellet is injected by the combined operation of a mechanical punch and a pneumatic propellant system. The pellet shape is cylindrical, 3 mm in diameter and 3 mm in length. Using this technique the speed of the pellet can be controlled flexibly in the range of 100-450 m/s, and a higher speed can be feasible for a higher gas pressure. The injector is equipped with a guide tube selector to direct the pellet to different injection locations. Pellets are exposed to several curved parts with the curvature radii R(c) = 0.8 and 0.3 m when they are transferred in guided tubes to the respective injection locations. Pellet speed variation with pressure at different pellet formation temperatures has been observed. Pellet intactness tests through these guide tubes show a variation in the intact speed limit over a range of pellet formation temperatures from 6.5 to 9.8 K. Pellet speed reduction of less than 6% has been observed after the pellet moves through the curved guide tubes. 相似文献
104.
Hiroki Kikuchi Shigeki Hashimoto Shinichiro Tajiri Tsuneo Hayashi Yutaka Sugawara Michio Oka Yoshiyuki Akiyama Akira Nakamura Naoya Eguchi 《Journal of the Society for Information Display》2009,17(3):263-269
Abstract— A high‐pixel‐rate, high‐contrast (30,000:1) wide‐color‐gamut grating‐light‐valve laser projector is reported. A new optical engine enabling high‐frame‐rate (240 Hz) scan projection is employed. Panoramic wide‐angle‐scan projection with a 64:9 aspect ratio was also developed. Speckle noise is eliminated using a simple but highly efficient technique. The optical throughput efficiency of the grating‐light‐valve laser projector is reviewed. 相似文献
105.
Takayuki Yamada 《Artificial Life and Robotics》2009,14(3):384-387
Although many neural network controllers have been proposed, we still have to tune several parameters of neural networks in
order to obtain a better learning performance in practical applications. Our tracking method provides a new aspect of this
tuning of neural network parameters. It has been applied to adaptive and learning-type neural network direct controllers,
and an adaptive-type neural network feed-forward feed-back controller. This work applied it to a learning-type neural network
feed-forward feed-back controller. Simulation results confirmed its usefulness, and we discuss a transformation of the track
on a 2D plane to one-dimensional values. 相似文献
106.
Rosa RG Tarsitano CA Hyslop S Yamada AT Toledo OM Joazeiro PP 《Microscopy research and technique》2008,71(3):169-178
In some animals, such as mice and guinea pigs, a hormonally controlled mechanism increases the flexibility of the pubic symphysis and enhances the cervical remodeling necessary for safe delivery. Cervical ripening during pregnancy is associated with a paradoxical influx of leukocytes. However, the changes in cell metabolism during relaxation of the mouse pubic symphysis for delivery have not been extensively studied. In this work, we used light microscopy and transmission and scanning electron microcopy, as well as immunohistochemistry and Western blotting for MMP-8, to investigate the involvement of granulocytes or resident stromal cells in the relaxation of the virgin pubic symphysis during late pregnancy (days 18 and 19, before delivery) in vivo and in explanted joints. MMP-8 was studied because this collagenase is a hallmark for cervical ripening associated with the influx of granulocytes during late pregnancy. Extensive dissolution and disorganization of the extracellular matrix was seen around fibroblastic-like cells in late pregnancy. In contrast to the cervix (positive control), morphological and immunohistochemical analyses revealed that there was no characteristic cellular inflammatory response in the interpubic tissue. Staining for MMP-8 was observed in chondroid and fibroblastic-like cells of virgin and relaxed interpubic ligament, respectively. However, no granulocytes were seen during the extensive remodeling of the pubic joint in late pregnancy. These results indicate that constitutive stromal cells may have an important role in tissue relaxation during remodeling of the pubic symphysis in pregnancy. 相似文献
107.
T Yamada 《Canadian Metallurgical Quarterly》1994,52(5):1311-1317
In an attempt to study "manic-depressive" affairs associated with endocrine and mental disorders, our clinical data are analyzed before and after appropriate treatment in Cushing's disease, Cushing's syndrome, hyperthyroid Graves' disease and primary hypothyroidism. Although our data do not provide definite findings on manic-depressive affairs associated with Cushing's disease and syndrome, review data by others indicated a high incidence of depression under untreated condition and its disappearance after appropriate treatment. In contrast, patients with adrenocortical insufficiency did have a depression but this was cleared after supplemental therapy. In hyperthyroid Graves' disease, a number of emotional and mental instability and irritability were noticed before the treatment, but these abnormalities all disappeared after appropriate treatment for 3-6 months. In contrast, patients with primary hypothyroidism did show lethargy and apathy, and these abnormalities disappeared after appropriate treatment. From the data accumulated, it is concluded that adrenal steroid and thyroid hormone do affect the functions of nervous system and, as a result, cause a number of clinical symptoms. The exact biochemical processes underlying these abnormalities are not known and remains for further investigations. 相似文献
108.
M. Okuya T. Kimura R. Kobayashi J. Shimoyama K. Kitazawa K. Yamafuji K. Kishio K. Kinoshita T. Yamada 《Journal of Superconductivity》1994,7(2):313-318
Large single crystals of (La1–x
Ca
x
)2CaCu2O6 were synthesized by the travelling solvent floating zone (TSFZ) technique. The dimension of the grown boules was typically 4 mm×30 mm long with thec-axis perpendicular to the growth direction. After oxygen loading at 1080°C in 400 atm of O2, they became superconductive with a sharp transition at around 50 K. The resistivity was metallic both along thec-axis and within theab-plane, with an anisotropy ratio of
2(
c/
ab
) 50 which is almost independent of temperature. Details of the crystal growth, heat treatment procedures, and the results of electrical and magnetic property measurements are presented. 相似文献
109.
A Takeshita H Sakamaki S Miyawaki T Kobayashi K Kuriyama O Yamada H Oh T Takenaka N Asou R Ohno 《Canadian Metallurgical Quarterly》1995,76(4):602-608
OBJECTIVE: For resuscitation of hemorrhagic hypovolemia, we compared the effectiveness of (1) isotonic lactated Ringer's solution (LRS), (2) 2400 mOsm of 7.5% NaCl:6% dextran 70 (HSD), and (3) 2400 mOsm of 7.9% sodium acetate:1.9% NaCl:6% dextran 70 (HAD). DESIGN: In six randomized, blinded experiments for each solution, conscious instrumented adult sheep were hemorrhaged by removing approximately 1.8 L (42 +/- 3 mL/kg) of blood, while maintaining the mean arterial pressure (MAP) at 50 mm Hg for 2 hours. METHODS: Test solutions were infused as needed to restore the cardiac index to baseline. RESULTS: Volume requirements with HAD (236 +/- 29 mL) and HSD (244 +/- 39 mL) were significantly less (p < 0.05) than LRS (3463 +/- 234 mL). Mean arterial pressure was normalized with HSD and LRS, but not with HAD, which resulted in MAPs of 20 to 25 mm Hg less than baseline resulting from a reduced peripheral resistance. Oxygen delivery, however, was significantly higher with HAD during the resuscitation period. Acid-base balance (pH) and oxygen consumption were normalized within 5 minutes of infusion only with HAD. CONCLUSIONS: Small-volume infusion with HAD resulting in "high-flow-low-pressure" resuscitation may offer unique hemodynamic and metabolic advantages for the initial treatment of hemorrhage from trauma. 相似文献
110.
Zihan Ma Xiaofei Lu Sunghyun Park Tatsuya Shinagawa Masashi Okubo Kazuhiro Takanabe Atsuo Yamada 《Advanced functional materials》2023,33(25):2214466
Hydrogen is a promising alternative to fossil fuels that can reduce greenhouse gas emissions. Decoupled water electrolysis system using a reversible proton storage redox mediator, where the oxygen evolution reaction and hydrogen evolution reaction are separated in time and space, is an effective approach to producing hydrogen gas with high purity, high flexibility, and low cost. To realize fast hydrogen production in such a system, a redox mediator capable of releasing protons rapidly is required. Herein, α-MoO3, with an ultrafast proton transfer property that can be explained by a dense hydrogen bond network in the lattice oxygen arrays of HxMoO3, is examined as a high-rate redox mediator for fast hydrogen production in acidic electrolytes. The α-MoO3 redox mediator shows both a large capacity of 204 mAh g−1 and fast hydrogen production at a current rate of 10 A cm−2(≈153 A g−1), outperforming most of the previously reported solid-state redox mediators. 相似文献