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111.
The In this paper, a simulator of a one‐wheel Electric Vehicle system is designed for testing an anti‐slip controller using the Motor‐Generator system. The drive motor of the M‐G system is used to simulate the drive wheel of the Electric Vehicle, and the load motor is used to simulate the load force of the chassis. In the driving process, the torque of the load motor is changed according to the drive force of the chassis that is calculated by the program. So it can simulate the dynamic process of the tire‐road system. Based on this simulator system, an anti‐slip controller based on an Adhesion Status Analyzer is proposed. Information about the wheel speed is acquired by using a Back EMF Observer. A load torque disturbance observer is designed to stabilize the acceleration of the wheels. The Adhesion Status Analyzer is used to generate safe acceleration commands for the anti‐slip controller. When a slip occurs, the anti‐slip controller will decrease the torque quickly, and at the same time, by estimating the dynamic status of adhesion, the Adhesion Status Analyzer will restrain the acceleration command within a safe area. The effectiveness of the proposed approach is verified by using the EV slip simulator. 相似文献
112.
The rare earth manganite BaLn2Mn2O7 (Ln=rare earth element) has a Sr3Ti2O7-type layered perovskite structure with double-block oxygen octahedra belonging to the Ruddlesden-Popper-type homologous series AO(ABO3)2. In Pr-manganite, a novel phase transition was first observed in situ at 1040 K by a thermal transmission electron microscope. At 1040 K, reflections began to split along the c-direction in the selected area diffraction pattern. This indicates that a new phase appears in the original phase matrix; the c length of the new phase is 1.5% longer than that of the original phase. After about 5 min, the original phase disappears. No change in the crystal symmetry (space group I4/mmm) is observed above 1040 K. 相似文献
113.
A. Matsubara K. Kawasaki H. Inaba S. Miyawaki O. Ishikawa T. Hata T. Kodama 《Journal of Low Temperature Physics》1999,114(3-4):349-370
We have measured the viscosity, , and the slip length, , of normal and superfluid
3
He using a torsional oscillator with a thick sample space. We coated the oscillating surface with 2.5 layers of
4
He film to study how the
4
He thin film changes the scattering mechanism of
3
He quasiparticles at the cell wall at 5 bar and 21 bar. In the normal phase, the temperature dependence of the viscosity was changed a little by the
4
He film at 21 bar but no change was observed at 5 bar. The slip length was enhanced by
4
He coating at 5 bar. This enhancement indicates the increase of specularity of
3
He quasiparticles scattering at the oscillating surface. On the other hand, a reduction of the slip length was observed at 21 bar. In the superfluid phase, the temperature dependence of supports the existence of Andreev reflection even with
4
He film on the surface at 5 bar and 21 bar. 相似文献
114.
D. Kim M. Nakagawa O. Ishikawa T. Hata T. Kodama H. Kojima 《Journal of Low Temperature Physics》1992,89(3-4):681-684
We report measurements on the effects of4He coverage and pressure on the fourth sound propagation in superfluid3He in confined geometries of four different pore sizes. 相似文献
115.
T Tsuji I Waga K Tezuka M Kamada K Yatsunami H Kodama 《Canadian Metallurgical Quarterly》1998,91(4):1263-1271
Cellular interactions between hematopoietic cells and stromal cells play important roles in the proliferation and differentiation of hematopoietic cells. The proliferation of a human erythroleukemia cell line, HEL cells, which can differentiate into macrophage- and megakaryocyte-like cells, and erythroid precursors was dramatically induced on coculture with a hematopoietic-supportive stromal cell line, HESS-5 cells, which can support long-term hematopoiesis in vitro without fetal bovine serum. HEL cells proliferated when they were cocultured with but not without direct cell contact. Because the coculture supernatants with direct cell contact and cytokines such as interleukins and growth factors did not exhibit growth-stimulating activity toward HEL cells, it was suggested that some molecule that has growth-stimulating activity exists on the surface of the cells. Extracellular matrix components such as fibronectin, laminin, vitronectin, and collagen did not affect the proliferation of HEL cells. An anti-CD18 monoclonal antibody, which recognizes the common beta chain of the beta2 integrin subfamily, induced dramatic proliferation of HEL cells. Moreover, the proliferation of HEL cells was inhibited by an antisense oligonucleotide of CD18 mRNA. As judged from these observations, the proliferation of HEL cells was mediated by CD18 molecules expressed on HEL cells. On the contrary, the common counter-receptor of the beta2 integrin subfamily, intercellular adhesion molecule-1, which is expressed on CHO-K1 cells, did not stimulate the growth of HEL cells. It is known that other counter molecules of the beta2 integrin subfamily, such as complement C3bi and fibrinogen, are not produced by stromal cells. These findings suggest that the proliferation of HEL cells may be induced through an interaction between a novel molecule of the beta2 integrin subfamily on HEL cells and the counter-receptor on HESS-5 cells. The beta2 integrin subfamily may regulate the growth of hematopoietic cells in hematopoiesis in vivo and/or cause the abnormal growth of leukemia cells. 相似文献
116.
M Kodama K Akiyama H Ujike Y Shimizu Y Tanaka S Kuroda 《Canadian Metallurgical Quarterly》1998,796(1-2):273-283
The effect of acute and chronic administration of methamphetamine (METH) on the levels of activity-regulated cytoskeleton-associated protein (arc), an effector-immediate early gene, mRNA has been investigated in rat brain using in situ hybridization. Levels of arc mRNAs in the brain regions examined increased significantly from 0.5-1 h after an acute METH (4 mg/kg) administration compared with basal levels. The increase in arc mRNA continued by 3 h, and then subsided to basal levels by 6 h. The degree of increase in arc mRNA and the peak time after METH administration varied according to brain area. Arc mRNA in cerebral cortices showed robust increase 1 h after METH administration. In the striatum and hippocampus, it showed earlier and later increase, respectively, and its degree of both was less than in the cortices. Microscopic examination revealed that the METH-induced arc mRNAs in the parietal cortex were enriched in layers IV and VI, and those in the striatum existed mainly in the medium-sized neuron. Pretreatment with either 0.5 mg/kg SCH23390 or 0.25 mg/kg MK-801 almost completely blocked the enhanced striatal arc mRNA levels induced by acute METH administration, whereas such pretreatments only partially reduced the effect of METH in the cerebral cortical regions. In the chronic treatment experiment, the arc mRNA levels of the group that received chronic treatment with METH followed by a METH challenge showed an increase like seen after acute METH administration. Since previous studies proposed that arc is one of cytoskeleton-associated proteins and is selectively localized in neural dendrites, the results of the present study suggested that arc may play an important role in the synaptic plasticity underlying METH-induced adaptational changes including behavioral sensitization. 相似文献
117.
Kiyotaka Uyeda Kohsaku Shimizu Naoki Maki Akinori Ueda Kaoru Itoh 《Electrical Engineering in Japan》1993,113(4):11-24
The application of superconductivity technology to electric power apparatus is very important from the viewpoint of energy saving. Especially, the superconducting generators using superconductors as the field windings have many merits compared with conventional generators. Super-GM has been researching and developing 70-MW-class model machines since FY 1988 for a scheduled period of eight years, aiming at a 200-MW-class superconducting generator. This paper describes the basic specifications and designs of 70-MW-class superconducting generators by Super-GM and also describes the propriety of these basic specifications and designs. 相似文献
118.
N Yahata K Ohyashiki O Iwase Y Kimura A Kodama K Fukutake K Toyama 《Canadian Metallurgical Quarterly》1998,22(9):845-847
We report the second case of post-myelodysplasia acute myeloid leukemia (post-MDS AML) with a sole chromosome change del(15q). This anomaly is rarely seen. To our knowledge, only seven cases so far have been reported in human neoplasias, including one case each of acute myeloid leukemia (AML), acute lymphoid leukemia, post myelodysplasia AML, myelodysplastic syndrome, myelofibrosis, macroglobulinemia, Hodgkin's lymphoma and uterine leiomyoma. This case suggests that del(15q) is related to lympho-myeloproliferative disorders. Moreover, we speculate that certain oncogene(s) located on 15q might have some role in the progression of the disease, since the del(15q) anomaly appeared only in the AML phase in this case. 相似文献
119.
T Baba N Yamashita H Kodama M Mukamoto M Asada K Nakamoto Y Nose ED McGruder 《Canadian Metallurgical Quarterly》1998,45(5):279-286
This article examines the 50-year struggle of osteopathic physicians to gain entry into the US Military Medical Corps on the same basis as allopathic physicians. The author explores various arguments put forth by both physician groups, as well as those arguments presented by the respective surgeons general and relevant government officials. 相似文献
120.
Minekazu Kodama 《Polymer Engineering and Science》1993,33(17):1141-1145
Dynamic mechanical and tensile properties were investigated for blends of poly(styrene-co-acrylonitrile) and bisphenol-A polycarbonate prepared by the solution process. It is apparent from the dynamic mechanical properties that the as-blended sample has a phase separated structure and the structure changes further with heat treatment. The phase structures of as-blended and heat-treated samples were estimated using the theories of Kerner and Davies for the modulus of two-phase materials and the dynamic mechanical data. The tensile properties obtained at room temperature are not inconsistent with the phase structure estimated for the as-blended and heat-treated samples. 相似文献