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排序方式: 共有2316条查询结果,搜索用时 15 毫秒
1.
Toshihiko Kujime Soong-Keun Hyun Hideo Nakajima 《Metallurgical and Materials Transactions A》2006,37(2):393-398
A lotus-type porous carbon steel with cylindrical pores was fabricated by the continuous zone melting method in a pressurized
mixture of hydrogen and helium gases. The porosity increases with increasing partial pressure of the hydrogen gas, while the
pore diameter remains almost constant, independent of the pressure. The ultimate tensile strength of the specimen with cylindrical
pores parallel to the tensile direction is lower than the estimated value, assuming that the strength is decreased in proportion
to the decrease of the cross-sectional area of the specimen, while the yield strength is higher than the estimated value.
The compressive yield strength is also higher than the estimated value. The increase in yield strength is considered to be
due to precipitation strengthening. The tensile strength is increased by quenching and tempering, while the elongation decreases.
Such mechanical properties are discussed in terms of the microstructural analysis. 相似文献
2.
Hasegawa M. Furutani S. Doki S. Okuma S. 《Industrial Electronics, IEEE Transactions on》2003,50(5):912-919
This paper proposes a method for designing a robust full-order observer for vector-controlled induction motors taking core loss into account. Although conventional research focuses on parameter identification, global stability of the identification remains questionable. Therefore, robustness against some parameters is required. This paper describes the design of a robust full-order observer which takes core loss into account, using both the gain-scheduled H/sub /spl infin// control and the linear matrix inequality technique. This design always results in a stable controller. The robustness of the proposed method against variations of resistances is evaluated by experiments. 相似文献
3.
Supermedia-enhanced Internet-based telerobotics 总被引:4,自引:0,他引:4
Elhajj I. Ning Xi Wai Keung Fung Yun-Hui Liu Hasegawa Y. Fukuda T. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》2003,91(3):396-421
This paper introduces new planning and control methods for supermedia-enhanced real-time telerobotic operations via the Internet. Supermedia is the collection of video, audio, haptic information, temperature, and other sensory feedback. However, when the communication medium used, such as the Internet, introduces random communication time delay, several challenges and difficulties arise. Most importantly, random communication delay causes instability, loss of transparency, and desynchronization in real-time closed-loop telerobotic systems. Due to the complexity and diversity of such systems, the first challenge is to develop a general and efficient modeling and analysis tool. This paper proposes the use of Petri net modeling to capture the concurrency and complexity of Internet-based teleoperation. Combined with the event-based planning and control method, it also provides an efficient analysis and design tool to study the stability, transparency, and synchronization of such systems. In addition, the concepts of event transparency and event synchronization are introduced and analyzed. This modeling and control method has been applied to the design of several supermedia-enhanced Internet-based telerobotic systems, including the bilateral control of mobile robots and mobile manipulators. These systems have been experimentally implemented in three sites test bed consisting of robotic laboratories in the USA, Hong Kong, and Japan. The experimental results have verified the theoretical development and further demonstrated the stability, event transparency, and event synchronization of the systems. 相似文献
4.
Sachiyuki Hasegawa Kazuyuki Shimizu Takeshi Kobayashi Masakazu Matsubara 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1985,35(1):33-42
Repeated batch operation using two fermentors (RBTF) to penicillin fermentation was demonstrated by computer simulation to improve productivity. Three operation modes were compared: chemostat, repeated batch operation using a single fermentor (RBSF) and RBTF; in each case account was made of the lag period before growth. The simulated fermentor performances were assessed on the basis of the penicillin productivity and concentration; the simulation was based on published batch fermentation data. It was shown that RBTF was superior to RBSF and chemostat. The advantage of RBTF increased as the lag period became greater. 相似文献
5.
Toshihiko Hoshide Junpei Fujita 《Journal of Materials Engineering and Performance》2008,17(5):627-632
Strength of ground ceramics may be affected by residual stress as well as surface flaws induced by grinding. Strength prediction
for ground ceramics is convenient for mechanical design of ceramic components. In this article, a numerical procedure based
on fracture mechanics was proposed to estimate strength distribution of ground ceramics by considering grinding-induced residual
stress. Bending strength and residual stress of ground ceramics were measured for three grinding-conditions. By comparison
of simulated results with experimental ones, it was revealed that strength characteristics in experiments were well simulated
by using the proposed procedure. 相似文献
6.
R Kano H Matshushiro T Watari H Tsujimoto A Hasegawa 《Canadian Metallurgical Quarterly》1997,40(9-10):335-341
To develop the molecular differentiation analysis of dermatophytes, we carried out RAPD and Southern hybridization analyses using genomic DNAs of six Arthroderma species, including A. fulvum, A. grubyi, A. gypseum, A. incurvatum, A. otae and A. racemosum. The RAPD analysis gave different band patterns specific to each of the six Arthroderma fungi. However, minor differences in the banding patterns were observed between the strains of plus (+) and minus (-) mating types of A. gypseum, A. fulvum and A. incurvatum. Southern blot analysis using a probe (1S) obtained from A. grubyi DNA gave specific bands only in the DNA samples of A. grubyi and A. incurvatum. On the other hand, Southern blot analysis using a probe (C3) obtained from A. otae DNA gave specific bands in all six Arthroderma species examined, and the size of the bands were specific to each species. These findings indicate that RAPD and Southern hybridization analyses are useful in the differentiation of these Arthroderma species. 相似文献
7.
8.
M Yaono R Hasegawa K Kato J Kimura C Lin M Tada T Shirai 《Canadian Metallurgical Quarterly》1996,98(2):145-149
We attempted to purify endogenous growth factors of chick embryonal retinal pigment epithelial cells from bovine neural retina. Ammonium sulfate precipitation, gel filtration, and anion exchange column chromatography were used. Though only partially purification, bovine retinal extract had two effects, growth and transformation, on chick embryonal pigment epithelial cells. We think that these purified factors may be novel from the estimation of their molecular weight by gel filtration. 相似文献
9.
10.
In this article, we consider a flexible beam with a rigid body, of which the bending vibration and the torsional vibration are decoupled. Therefore we need two control motors to suppress the vibrations. Each set of dynamic equations is treated in the form of an appropriate Hilbert space. A stabilizing feedback control law of each rotation motor will be established on the basis of modal analysis. A set of experiments has been carried out, and the results demonstrate the effectiveness of the dynamic model and the proposed control law. © 1994 John Wiley & Sons, Inc. 相似文献