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81.
Shiozaki J. Shibata B. Matsuyama H. O'shima E. 《Industrial Electronics, IEEE Transactions on》1989,36(4):469-474
The fault diagnosis algorithms using a signed directed graph (SDG) as a model of the system is useful in the real-time diagnosis of failures that occur in chemical processes. The accuracy of the algorithm has been improved so that it can select the candidates that are most likely to be the real origin of failure, utilizing the time when the measured variables begins to show abnormality as the representation of the dynamic characteristic of the measured variable. The accuracy and speed of the improved algorithm have been examined by its application to data obtained in fault diagnosis experiments on tank-pipeline systems 相似文献
82.
This paper presents the results of a research into capacitor discharge percussion welding (CDPW) of pure aluminum wires and pure copper sheets, using percussion welding power and special welding device. A lot of CDPW factors, which will affect aluminum and copper dissimilar bonding, are described and these parameters have also been optimized. The fracture pull, inter'ace compounds, microstructure and hardness are all studied. The results show that aluminum wire welding to copper sheet can form a sound weld and in some conditions the fracture pull is similar to that of the pure aluminum wires. The capacitance, discharge voltage, wire taper angle and machine oil as welding assistant medium affect fracture pull. The intermetallic compounds Al2 Cu appears on the copper side of joint. Narrower heat-affected zone is observed. 相似文献
83.
The response of the structure subjected to nonstationary random vibration such as earthquake excitation is nonstationary random vibration. Calculating method for statistical characteristics of such a response is complicated. Mean square value of the response is usually used to evaluate random response. Integral of mean square value of the response corresponds to total energy of the response. In this paper, a simplified calculation method to obtain integral of mean square value of the response is proposed. As input excitation, nonstationary white noise and nonstationary filtered white noise are used. Integrals of mean square value of the response are calculated for various values of parameters. It is found that the proposed method gives exact value of integral of mean square value of the response. 相似文献
84.
Shigeru Okada Toetsu Shishido Takao Mori Kiyokata Iizumi Kunio Kudou Kazuo Nakajima 《Journal of Alloys and Compounds》2008,458(1-2):297-301
LEAlB14 (orthorhombic, Imam) (LE = Li, Mg) crystals were grown using metal salts (Li2CO3, LiF, LiI, MgO, MgF2, MgI2) and crystalline boron from a high-temperature aluminium metal flux. The growth conditions for growing LEAlB14 were established using the starting mixtures of B/LE = 2.0, and Al metal was added to each mixture at a mass ratio of 1:15–20. LEAlB14 crystals from the Al-self flux using metal salts could be obtained from all the different salts. The maximum dimensions of LiAlB14 and MgAlB14 crystals were approximately 18 and 12 mm for the crystals obtained from LiF and MgF2. The unit-cell parameters of as-grown LEAlB14 are as follows: for LiAlB14, obtained from LiF, a = 0.5846 (2) nm, b = 0.8144 (2) nm, c = 1.0355 (3) nm, V = 0.4930 (2) nm3: for MgAlB14, obtained from MgF2, a = 0.5845 (2) nm, b = 0.8114 (2) nm, c = 1.0330 (3) nm, V = 0.4899 (3) nm3. Microhardness, oxidation resistance and magnetic susceptibility of these materials are described in detail. 相似文献
85.
86.
One of the most important technologies for electric vehicles (EVs) will be drive control technology for the main motor. It is desired that the drive control technology have the following characteristics. (1) It does not require a position/speed sensor for controlling motor drive, which has been mounted on the rotor shaft. (2) It has vector controls that can produce torque quickly, efficiently, and/or precisely. (3) It has wide driving‐range and allows developing EVs with no variable transmission. This paper proposes new drive control technologies for such EVs using a permanent‐magnet synchronous motor as a main motor, and verifies its usefulness through development of an actual EV that can drive on public roads. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 165(3): 83–94, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20459 相似文献
87.
Air-core photonic bandgap fibers offer many unique properties and are critical to many emerging applications. A notable property is the high nonlinear threshold which provides a foundation for applications at high peak powers. The strong interaction of light and air is also essential for a number of emerging applications, especially those based on nonlinear interactions and spectroscopy. For many of those applications, much wider transmission bandwidths are desired to accommodate a wider tuning range or the large number of optical wavelengths involved. Presently, air-core photonic bandgap fibers have a cladding of hexagonal lattice. The densely packed geometry of hexagonal stacking does not allow large nodes in the cladding, which would provide a further increase of photonic bandgaps. On the other hand, a photonic cladding with a square lattice can potentially provide much larger nodes and consequently wider bandgap. In this work, the potentials of much wider bandgap with square lattice cladding is theoretically studied and experimentally demonstrated. 相似文献
88.
Yuichi Ichihashi Yo-hei Kamizaki Naoya Terai Keita Taniya Shigeru Tsuruya Satoru Nishiyama 《Catalysis Letters》2010,134(3-4):324-329
The gas-phase catalytic oxidation of benzene over copper supported on HZSM-5 added with titanium (Cu/Ti/HZSM-5) was carried out by using molecular oxygen as an oxidant. Phenol was effectively produced by the titanium addition to Cu/HZSM-5. The titanium addition to Cu/HZSM-5 induces the easy reduction of Cu2+ species to Cu+ species in the catalysts, and the produced Cu+ species seems to produce the phenol effectively. 相似文献
89.
Shigeru Sugiyama Yuhki Kato Takahiro Wada Shirou Ogawa Keizo Nakagawa Ken-Ichiro Sotowa 《Topics in Catalysis》2010,53(7-10):550-554
MCM-41 and FSM-16 were both prepared using no hydrothermal conditions, and nickel was doped into these catalysts (Ni-MCM-41 and Ni-FSM-16) using a template ion exchange method. FSM-16 and Ni-FSM-16 had greater catalytic activity for the conversion of ethanol than MCM-41 and Ni-MCM-41, indicating that FSM-16 has potential as a catalyst for the conversion of ethanol to propylene. 相似文献
90.
Tomoharu Suzuki Shigeru Oshio Mari Iwata Hisayo Saburi Takashi Odagiri Tadashi Udagawa Isamu Sugawara Masakazu Umezawa Ken Takeda 《Particle and fibre toxicology》2010,7(1):1-8