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71.
Satoshi Suzuki Yaodong Pan Katsuhisa Furuta Shoshiro Hatakeyama 《Asian journal of control》2004,6(3):307-316
In general, a Variable Structure (VS) system is designed with a sliding mode. Recently a sliding sector, designed by an algebraic Riccati equation, has been proposed to replace the sliding mode for chattering‐free VS controllers. In this paper we extend the design algorithm for the sliding sector to a time‐varying sliding sector. The time‐varying sliding sector is defined by functions dependent on both state and time, hence time‐varying uncertainty can be considered. The VS controller is designed to stabilize an uncertain system, quadratically. The design procedure for real systems is introduced via an implementation to the control of “Furuta pendulum”. To enhance the stability it is necessary to compensate the time‐varying nonlinear static friction of the actuator adequately, hence this problem is a good example to demonstrate the performance of the proposed VS control method. In the experiment, it will be shown that the VS control with the time‐varying sliding sector is superior to an orthodox chattering‐free VS control. 相似文献
72.
Masahiro Ishida Toru Nakura Takashi Kusaka Satoshi Komatsu Kunihiro Asada 《Journal of Electronic Testing》2016,32(3):257-271
This paper proposes a power integrity control technique for dynamically controlling power supply voltage fluctuations for a device under test (DUT), and demonstrates its effectiveness for eliminating the overkills/underkills due to the difference of power supply impedance between an automatic test equipment (ATE) and a practical operating environment of the DUT. The proposed method injects compensation currents into the power supply nodes on the ATE system in a feed-forward manner such that the ATE power supply waveform matches with the one on the customer’s operating environment of the DUT. A method for calculating the compensation current is also described. Experimental results show that the proposed method can emulate the power supply voltage waveform under a customer’s operating condition and eliminate 95 % of overkills/underkills in the maximum operating frequency testing with 105 real silicon devices. Limitations and applications of the proposed method are also discussed. 相似文献
73.
Thermoplastic resins are typically used without any kind of physical aging treatment. For such materials, creep behavior and physical aging, which depend on time and temperature, occur simultaneously. The effects of these processes are evident after quenching and are recorded in the material as a thermal history. This history strongly influences mechanical properties and creep behavior in particular. Thus, a more thorough understanding of the physical aging process is desirable. We examined the creep deformation of polycarbonate (PC) to reveal the effects of physical aging on creep behavior. The effects were dependent on both time and temperature. The relationship between physical aging and creep behavior exemplified superposition principles with regard to time and both pre-test aging time and pre-test aging temperature. The superposition principles allowed the calculation of creep deformations at a given temperature; the calculated results were corroborated by experimental data. 相似文献
74.
Energy Savings through Microwave Selective Heating of Pd/AC Catalyst Particulates in a Fixed‐Bed Reactor 下载免费PDF全文
Microwave radiation is a novel energy source to drive chemical reactions. In conventional reactors, however, the heat created either escapes through uninsulated reactor walls, or the microwave radiation is attenuated by insulated walls. Here, microwave selective heating of Pd catalyst particles supported on activated carbon particulates was examined in a fixed‐bed reactor using a novel vacuum‐filled Dewar‐like double‐walled continuous‐flow reactor. This reactor was developed toward energy savings in performing such organic reactions as the transformation of the hydride methyl cyclohexane to toluene. 相似文献
75.
76.
Satoshi Suganuma Haiyan Zhang Chengguang Yang Feng-Shou Xiao Naonobu Katada 《Journal of Porous Materials》2016,23(2):415-421
The acidic property of a BEA zeolite prepared by a seed-directed synthesis (SDS) method without organic structure directing agent (OSDA) was analyzed by a method of ammonia infrared/mass spectroscopic temperature-programmed desorption. The number of Brønsted acid sites on the SDS-BEA zeolite was larger than that on a conventional BEA zeolite synthesized from using OSDA. The enthalpy of ammonia desorption, distributed mainly in a range between 115 and 145 kJ mol?1, was in agreement with the acid strength region generated by isomorphous substitution of Si4+ by Al3+ in the BEA framework. These observations confirm that the microstructure around the incorporated Al in the SDS-BEA zeolite was equivalent to that in the conventional one. 相似文献
77.
78.
Atsushi Iizuka Satoshi Takeda Kazukiyo Kumagai Yukio Yanagisawa 《Chemical Engineering Communications》2017,204(3):321-326
The effect of the addition of microbubbles on the formation of silver nanoparticles produced in an ultrasonic radiation-mediated process was investigated. The addition of microbubbles with an area-based median diameter of 26.0?µm and a bubble volume density of 0.18?cm3/L significantly increased the silver nanoparticle formation rate during the sonochemical process. The size distribution of the silver nanoparticles was largely unaffected by the addition of the microbubbles. The influence of changes in the microbubble volume density on the formation of the silver nanoparticles was also investigated; it was confirmed that the rate of formation of the silver nanoparticles increased moderately with increasing volume density. The gradient in absorption spectra was approximately 30 times larger for the case when microbubbles (median diameter: 28.3?µm) were added at 0.74?cm3/L, compared with the case without microbubbles. The results suggested that the microbubbles provided reaction sites similar to cavitation bubbles in the ultrasonic reaction. 相似文献
79.
80.
Kazuo Nakajima Satoshi Ono Ryota Murai Yuzuru Kaneko 《Journal of Electronic Materials》2016,45(6):2837-2846