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991.
A stable high-order delta-sigma modulator topology is presented. The topology can be completely stabilized for arbitrary order by a finite impulse response (FIR) spectrum distribution technique. The stability of the modulator is examined by means of the root locus method. The topology inherently has less sensitivity to component mismatch, and can be realized without any hardware penalty compared to noise-shaping integrators of the same order. The modulator realizes 16-b resolution at 20-kHz bandwidth when a filter order of four and an oversampling ratio of 64 are employed 相似文献
992.
Biaxial stretching of polypropylene sheets containing CaCO3 filler results in microporous sheets, that feel soft and dry. Their properties depend on filler content, particle size of the filler, and stretching degree etc. We have studied the dependency of some properties of the microporous polypropylene sheets on stretching degree. It is elucidated that mechanical properties are controllable by adjusting stretching degrees in machine and transverse directions. © 1993 John Wiley & Sons, Inc. 相似文献
993.
WT Ford N Qi AL Read JG Smith T Camporesi De Sangro R I Peruzzi M Piccolo RB Hurst J Pyrlik JP Venuti R Weinstein MW Gettner GP Goderre JC Sleeman von Goeler E GB Chadwick RE Leedy RL Messner LJ Moss F Muller HN Nelson DM Ritson LJ Rosenberg DE Wiser RW Zdarko DE Groom PG Verdini HR Band MC Delfino JR Johnson TL Lavine T Maruyama R Prepost 《Canadian Metallurgical Quarterly》1987,36(7):1971-1982
994.
995.
996.
A. Takagi K. Maruyama 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》1992,7(4):347-353
In-ground storage tanks for liquefied natural gas (LNG) have two very gnificant advantages: structural safety and effective land use. Convinced of these beneficial properties of in-ground storage tanks, Tokyo Gas began an R&D programme in 1964. Since then, 24 storage units have been completed, another four units are now under construction, and two units are in the planning stage. Recently the construction business environment in Japan has had to face the challenges of an increase in aged workers, a shortage of skilled workers, a rapid increase in labor costs, and a slowing increase in productivity. These problems are now attracting general attention in Japan. The paper describes the latest construction technologies for LNG in-ground storage tanks, with particular attention to R&D aimed at solving the aforementioned problems, e.g., by shortening the construction period, lessening the manpower required, and aiming at a high level of safety in construction. The technical tasks required to attain the huge capacity of the tank are also descibed. 相似文献
997.
The breakup of a flowing liquid jet surrounded by a second flowing liquid is governed by capillary instabilities. These instabilities are caused by minor perturbations in the flow field that build up sinusoidal waves at the jet interface and eventually break it up. The phenomenon of such fatal wavelengths was described first by Lord Rayleigh and later extended by several authors to quiescent and flowing liquid‐liquid systems. The jet formation in a co‐flowing environment was only recently investigated. Originating from the forced breakup of liquid jets in air, this paper reports on the breakup mechanism of liquid jets surrounded by a fluid. By using different flow cells and consequently different flow profiles along the jet trajectory, the breakup mechanism given by the material and process parameters could be excited or suppressed. Two questions concerning droplet generation and the droplet size distribution are addressed: the suppression of the fatal wavelength in transient flow fields and the use of external flow fields to support the fatal wavelength. 相似文献
998.
999.
Yamasawa K. Maruyama K. Hirohama I. Biringer P.P. 《IEEE transactions on magnetics》1990,26(3):1204-1209
The operation of a multilayered microtransformer composed of planar zig-zag coils and amorphous magnetic film is described. The transformer has a maximum efficiency of 77.5%. Its equivalent circuit is approximated by the parallel connection of the winding inductance and of the stray capacitance. Variable magnetic coupling is obtained between the primary and secondary windings by shifting the relative position of the two coils. The microtransformer is used in a magnetically controlled multilayered switching regulator. The regulator has an output of 1.4 W and an efficiency of 24%. The magnetization loss in the circuit is the same as that of the semiconductors. A two-output-type multilayered switching regulator is also proposed that has an acceptably good output characteristic at each port even though a common magnetic film is used 相似文献
1000.
Yoshihiro Takao Hiroshi Kudo Junichi Mitani Yoshiyuki Kotani Satoshi Yamaguchi Keizaburo Yoshie Kazuo Sukegawa Nobuhisa Naori Satoru Asai Michiari Kawano Takashi Nagano Ikuhiro Yamamura Masaya Uematsu Naoki Nagashima Shingo Kadomura 《Microelectronics Reliability》2002,42(1)
This paper describes a 0.11 μm CMOS technology with high-reliable copper (Cu) and very low k (VLK) (k<2.7) interconnects for high-performance and low-power applications of a 0.13 μm generation. Aggressive design rules, 0.11 μm gate transistor and 2.2 μm2 six-transistor SRAM cell are realized by using KrF 248 nm lithography, optical proximity effect correction, and gate-shrink techniques. Eight-level interconnects are fabricated with seven level of Cu/VLK interconnect and one level of Al/SiO2 interconnect. Drain current of 0.67 and 0.28 mA/μm are realized for nMOSFET and pMOSFET with 0.11 μm gate, respectively. Propagation delay of two input NAND with the Cu/VLK interconnect is estimated. The delay is improved by more than 70%, compared to 0.18 μm CMOS technology with Cu/FSG interconnects. Functional 288 kbit SRAM circuit is demonstrated with 2.2 μm2 cell and Cu/VLK interconnect. 相似文献