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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Fuzzy model-based control of complex plants 总被引:1,自引:0,他引:1
In the field of fuzzy modeling, the Takagi-Sugeno fuzzy model has been used to approximate accurately the dynamics of complex plants. The paper addresses two control design problems associated with state-space realizations of such fuzzy models. First, we treat the stability robustness of fuzzy model-based controllers against modeling uncertainty. Second, we develop observer-based control schemes and further investigate the behavior of estimated-state feedback. In both cases, we provide sufficient conditions that guarantee stability of the closed loop. The results are demonstrated on the fuzzy model of a gas furnace process 相似文献
992.
WJ Cho EK Kim MJ Park SU Choi CO Lee SH Cheon BG Choi BH Chung 《Canadian Metallurgical Quarterly》1998,6(12):2449-2458
In this study a series of 3-arylisoquinoline derivatives were synthesized and cytotoxicity against human melanoma tumor cell evaluated, and a three dimensional quantitative structure-activity relationship was investigated using the comparative molecular field analysis (CoMFA). The results suggested that the electrostatic, steric and hydrophobic factors of 3-arylisoquinolines were strongly correlated with the antitumor activity. Considerable predictive ability (cross-validated r2 as high as 0.721) was obtained through CoMFA. 相似文献
993.
K Yun 《Canadian Metallurgical Quarterly》1998,13(2):425-435
The solution structure of a synthetic ET(B) selective agonist, ET-1[Cys(Acm)(1,15), Ala3, Leu7, dAsp8, Aib11] has been solved by 1H NMR and molecular modelling studies. Such solution structures of linear modified peptides in aqueous methanol are being used in an ongoing program of research designed to assist in an understanding of the basic structural requirements for the biological activity of vasoconstrictors. The resulting structure of this peptide is characterised by an alpha-helical conformation between residues Leu6-His16 and by N- and C-termini which assume no defined conformation. A knowledge of the solution structures of this and related peptides, which are ET(B) selective agonists, are proving to be important in the understanding of how they interact with the ET(B) receptor. 相似文献
994.
RY Calne S Thiru P McMaster GN Craddock DJ White DJ Evans DC Dunn BD Pentlow K Rolles 《Canadian Metallurgical Quarterly》1998,9(9):1751-1756
A psychrotrophic yeast, Rhodotorula glutinis KUJ 2731, isolated from soil, effectively produced an extracellular endo-beta-glucanase (EC 3.2.1.4). The enzyme was monomeric, and the molecular mass was about 40,000 Da. The N-terminal amino acid sequence was H-Ser-Leu-Pro- Lys-Leu-Gly-Gly-Val-Asp-Leu-Ala-Gly-Leu-Asp-Ile-Gly-Lys-Asp-Lys-Asn-. alpha-Helix content was calculated to be about 32.6%. The isoelectric point was 8.57. The activation energy was 20.9 kJ/mol, which was much smaller than that of mesophilic enzymes. The enzyme was active at temperatures from 0 to 70 degrees C, with a highest initial velocity at 50 degrees C similar to other psychrotrophic enzymes. The enzyme was inhibited by Hg2+. The enzyme catalyzed hydrolysis of carboxymethyl cellulose with an apparent K(m) of 1.1% and Vmax of 556 mumol/min/mg. Products from the enzymatic hydrolysis of carboxymethyl cellulose by the enzyme were glucose, cellobiose, and cellotriose. The enzyme also catalyzed the transglycosylation of p-nitrophenyl-beta-cellotrioside to cellotetraose. 相似文献
995.
K Shinno S Ueda M Uno K Nishitani S Nagahiro M Harada 《Canadian Metallurgical Quarterly》1998,38(9):557-561
OBJECTIVE: Epidemiological evidence suggests that resistance to insulin is the common nexus of the accumulation of factors in patients at high cardiovascular risk. To find a test which enables resistance to insulin to be identified in large populations will allow preventive and therapeutic measures to be taken. DESIGN: Crossover. SETTING: Carrascosa del Campo and Cuenca Health Centres. PARTICIPANTS: 408 patients (154 men and 254 women), all the non-diabetic obese patients at the two health centres, were studied. MEASUREMENTS AND MAIN RESULTS: Levels of cholesterol, triglycerides and uric acid were measured. Patients were medically examined, and blood pressure, waist and hip measurements, toxic habits and cardiovascular history were found. They were classified by pathology and normograms. The O'Sullivan and microalbuminuria tests were performed, and all the statistical associations with biochemical and medical characteristics were studied. The O'Sullivan test was significantly associated (p < 0.01) with cardiovascular risk and insulin-resistance factors such as hypercholesterolaemia (RR 1.63), hypertension (RR 1.92), hypertriglyceridaemia (RR 2.47), hyperuricaemia (RR 1.80), with the Berglund resistance index (RR 1.52) and the microalbuminuria test (RR 1.83). The association was more consistent when there were a number of factors combining. There was no relationship with the waist/hip index found. CONCLUSION: The O'Sullivan test, on its own or with the microalbuminuria test, seems very useful for identifying obese subjects with resistance to insulin. 相似文献
996.
Uchiyama K. Arakawa F. Narita S. Aoki H. Kawasaki I. Matsui S. Yamamoto M. Nakagawa N. Kudo I. 《Micro, IEEE》1993,13(5):12-22
The Gmicro/500, which features a RISC-like dual-pipeline structure for high-speed execution of basic instructions and represents a significant advance for the TRON architecture, is presented. Upwardly-object-compatible with earlier members of the Gmicro series, this microprocessor uses resident dedicated branch buffers to greatly enhance branch instruction execution speed. Its microprograms simultaneously use dual execution blocks to execute high-level language instructions effectively. Fabricated with a 0.6-μm CMOS technology on a 10.9-mm×16-mm die, the chip operates at 50/66 MHz and achieves a processing rate of 100/132 MIPS 相似文献
997.
Heidel D.F. Bapst U.H. Jenkins K.A. Geppert L.M. Zabel T.H. 《IEEE transactions on nuclear science》1993,40(2):127-134
An ion microbeam radiation test system has been built for studying radiation-induced charge collection and single event upsets in advanced semiconductor circuits. With this system, it is possible to direct an ion beam of a diameter as small as 1 μm onto a circuit or test structure with a placement accuracy of 1 μm. The components of the system and its operation are described. Applications are described which demonstrate the capabilities of the system 相似文献
998.
We recorded the highest age at the time of death for both men and women in Norway for the years 1970 to 1995. During this period longevity increased by approximately one year; for women from 106 to 107 years and for men from 105 to 106 years. Based on Gumbel's theory, we have estimated the most probable highest age for the next 10, 20, and 100 years. For women this was found to be 109, 110 and 113 years, respectively; for men the corresponding ages were 108, 109 and 112 years. Our aim must be that as many men and women as possible live to a high age, that their latter years are meaningful, and that they enjoy a high standard of living. 相似文献
999.
The 1,3-specific lipase-catalyzed interesterified fats were distinguished from chemically catalyzed products by the fatty
acids in the 2-position. The fatty acid contents in the 2-position of the 1,3-lipase-catalyzed and the original triglycerides
were similar but different from that of chemically interesterified fat. Also, the saturated-to-unsaturated fatty acid ratio
in the 2-monoglycerides was lower for the 1,3-specific lipase-catalyzed interesterified fats than for the corresponding chemical
products. 相似文献
1000.