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31.
In this study, trajectory tracking fuzzy logic controller (TTFLC) is proposed for the speed control of a pneumatic motor (PM).
A third order trajectory is defined to determine the trajectory function that has to be tracked by the PM speed. Genetic algorithm
(GA) is used to find the TTFLC boundary values of membership functions (MF) and weights of control rules. In addition, artificial
neural networks (ANN) modelled dynamic behaviour of PM is given. This ANN model is used to find the optimal TTFLC parameters
by offline GA approach. The experimental results show that designed TTFLC successfully enables the PM speed track the given
trajectory under various working conditions. The proposed approach is superior to PID controller. It also provides simple
and easy design procedure for the PM speed control problem. 相似文献
32.
33.
Manuel A. Silva Anderson Veronese Anna Belli Ed H. Madureira Klibs N. Galvão Ricardo C. Chebel 《Journal of dairy science》2021,104(3):3439-3457
Automated monitoring devices (AMD) have become more affordable, and consequently more popular among dairy producers. We hypothesized that the addition of AMD-generated health alerts to a health-screening program improves survival, milk production, and reproductive success. In addition, we hypothesized that cows diagnosed with clinical disease that have AMD alerts are at greater risk of culling, lower milk production, and decreased risk of pregnancy than cows without AMD alerts. Holstein cows (nulliparous = 282, parous = 328) were enrolled at ?60 ± 3 d (d 0 = calving), when they were fitted with an AMD and assigned randomly to 1 of 2 health-screening strategies: (1) control: AMD alerts not provided to farm personnel; and (2) automated device: AMD alerts provided to farm personnel. Twice daily, study personnel determined which cows had AMD alerts (health index ≤79, rumination <200 min/d, or difference between current rumination and the average of the 3 preceding days <0) and provided the information to farm personnel. Farm personnel examined cows at 3, 5, and 9 d in milk (DIM) and when daily milk yield decreased ≥25% on consecutive days. We detected no differences between health-screening strategies regarding morbidity (control = 49.7 ± 3.3%, automated device = 52.8 ± 3.2%), but the interaction between health-screening strategy and parity tended to be associated with the number of clinical diseases per cow (primiparous: control = 0.46 ± 0.06, automated device = 0.65 ± 0.07 cases/cow; multiparous: 0.88 ± 0.08, automated device = 0.86 ± 0.08 cases/cow). Cows enrolled in the automated device strategy were more likely to be treated with supportive therapy (64.4 ± 3.1 vs. 55.0 ± 3.2%), whereas primiparous cows in the automated device strategy were more likely to be treated with anti-inflammatory drugs than those in the control strategy (41.6 ± 4.7 vs. 23.8 ± 4.0%). Health-screening strategy did not affect survival or total milk yield up to 22 wk postpartum, but cows in the automated device strategy had reduced risk of pregnancy after the first 2 services (54.5 ± 3.0 vs. 46.2 ± 3.2%). Cows diagnosed with a clinical disease without AMD alerts had reduced risk of removal from the herd by 150 DIM (5.7 ± 2.0 vs. 19.0 ± 3.3%), greater risk of pregnancy after the first 2 services (49.6 ± 4.5 vs. 33.6 ± 3.9%), and greater milk by 22 wk postpartum (6.7 ± 0.2 vs. 5.3 ± 0.2 × 103 kg) than cows diagnosed with a clinical disease that had an AMD alert. Adding AMD-generated health alerts to the health screening of postpartum cows in a herd with an existing screening program did not improve survival, milk yield, or reproductive success. In addition, AMD alerts in cows diagnosed with a clinical disease may be indicative of the future success of such cows. 相似文献
34.
35.
G Belli A D'Agostino A Iannelli G Rotondano P Ceccarelli 《Canadian Metallurgical Quarterly》1997,52(9):1119-1121
Agenesis of the gallbladder and cystic duct is a rare congenital malformation. In 40-70% of cases this anomaly is associated with other gastrointestinal, skeletal, cardiovascular and genitourinary malformations. Lithiasis of the common bile duct is present in 25-50% of cases. In the majority of cases patients are asymptomatic or have symptoms compatible with a biliary disorder. A preoperative diagnosis is extremely difficult and the absence of the gallbladder is often an intraoperative finding. The authors report a case of isolated agenesis of the gallbladder. The relative embryology, development, diagnostic pitfalls, intraoperative behaviour and therapeutic strategies are discussed. 相似文献
36.
Two cases of patients with massive haemoptysis undergoing bronchial arteriography are described. Both had collateral vessels which filled the right subclavian artery from the right intercosto-bronchial trunk. Such vessels form a potential route for the passage of embolic material into the subclavian artery and its branches during therapeutic bronchial artery embolization. To avoid this potential complication, super selective catheterization with the positioning of the catheter tip well into the bronchial artery beyond the origin of the intercostal artery and any large collateral vessels is recommended. 相似文献
37.
O Levendoglu-Tugal J Munoz A Brudnicki M Fevzi Ozkaynak C Sandoval S Jayabose 《Canadian Metallurgical Quarterly》1998,27(5):1227-1230
We reviewed the spectrum of infections due to nontuberculous mycobacteria (NTM) in children with leukemia. Three children acquired such infections. One patient developed pneumonia after the cessation of chemotherapy when Mycobacterium xenopi was identified in his lung biopsy specimen. He required 2 years of treatment with antituberculous agents and clarithromycin. Cultures of central and peripheral blood specimens from two patients yielded Mycobacterium fortuitum and Mycobacterium chelonae, respectively. Broviac catheters were likely the source of infection. Removal of the catheters and antibiotic treatment resulted in cure. Central venous catheters in leukemic children are potential sources of infection. For febrile neutropenic children with leukemia who do not respond to antibiotic therapy, cultures positive for diphtheroids or negative routine bacterial and fungal cultures should raise a suspicion for infections due to NTM. Systemic infections may require up to 2 years of therapy. Removal of the infected catheters during persistent or recurrent infections in necessary for control of the infection. 相似文献
38.
R Raffoul MS Uva G Rescigno E Belli M Scorsin F Pouillart A Lessana 《Canadian Metallurgical Quarterly》1998,113(5):1296-1301
Recurrent urinary tract infections (RUTI) are a significant health problem for many women, and host characteristics that increase susceptibility are not completely defined. This study evaluated data from 99 patients to examine further the question of a possible association between major histocompatibility complex (MHC) or red blood cell (RBC) antigen phenotype and predisposition to RUTIs. MHC class I and II, ABO, and Lewis RBC phenotypes were determined serologically. The MHC class II phenotypes of 55 subjects were also determined by DNA polymerase chain reaction techniques. There were no significant differences in the proportions of HLA-A or -B antigen types between patients and controls, nor in the frequencies of serologically or DNA-defined HLA-DR or -DQ phenotypes. Patient ABO and Lewis RBC phenotypes were not statistically different than those for controls. Thus, the overall risk for women to develop RUTIs does not appear to be associated with any single HLA, ABO, or Lewis phenotype. 相似文献
39.
40.
Fevzi Ç. Cebeci 《Electrochimica acta》2007,52(5):2158-2165
The synthesis and characterization of a novel donor acceptor donor type bis(3,4-ethylene-dioxythiophene)-(4,4′-dinonyl-2,2′-bithiazole) comonomer and its electrochemically prepared polymer on carbon fiber, Pt button and ITO plate is reported in this paper. Cyclic voltammetry of the polymer in 0.1 M Et4NBF4/CH2Cl2 exhibits a very well defined and reversible redox processes and this co-monomer can be either p-doped or n-doped. The half-wave oxidation potentials of the polymer (E1/2) were observed at 0.303 and 0.814 V versus Ag/AgCl. The polymer is electrochromic; the onset for the π-π* transition (Eg) of 1.75 eV with a λmax at 2.15 eV and the homogeneous and high quality film of the polymer is stable of its optical properties offering fast switching time which is less than 0.25 s. The morphological studies reveal that the polymer was deposited as a continuous and very well adhering film to surface of the carbon fiber microelectrode. All these properties make this polymer favorable for use in electronic devices. 相似文献