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81.
The degenerative osteoarthritis (DOA) is a common disease of aged people. But its pathogenesis and mechanism are not very clear. We compared the Nitric Oxide content in knee fluid of DOA with the normal people as matched age. The results indicated that the Nitric oxide has a high concentration in DOA. This suggested that the Nitric Oxide may play an important role in the mechanism of this disease. 相似文献
82.
多级映射原理在符号化测量中的应用 总被引:7,自引:0,他引:7
本文提出了实现数值-符号转换的一种新方法,多级映射法,多级映射原理对于扩大符号表示概念的范围和细致程度非常有用,可用以实现数值和符号测量,并同时对传感器进行非线性修正,该方法在以热偶为低感温元件的模糊温度传感器上的应用表明,多级映射原理是可行和有效的。 相似文献
83.
84.
With every finite-state word or tree automaton, we associate a binary relation on words or trees. We then consider the rectangular decompositions of this relation, i.e., the various ways to express it as a finite union of Cartesian products of sets of words or trees, respectively. We show that the determinization and the minimization of these automata correspond to simple geometrical reorganizations of the rectangular decompositions of the associated relations.This work was supported by the Programme de Recherches Coordonnées: Mathématiques et Informatique. It was initiated during a stay in Bordeaux by D. Niwinski in 1988. 相似文献
85.
Iyer Harish Tafaghodi Khajavi Leili Durlik Damian Danaei Karim Barati Mansoor 《SILICON》2018,10(5):2219-2226
Silicon - An experimental study was conducted to characterize the interaction between liquid silicon and refractory inclusions that are often present in silicon as solid inclusions. The... 相似文献
86.
The Darcie-Whalen reflection method is ambiguous and has a chart area of 72%, which is less sensitive than method H-Owen's classification-which is unambiguous and has a chart area of 100%. 相似文献
87.
In this paper, we consider the predictive control problem of designing receding horizon controllers for networked linear systems subject to random packet loss in the controller to actuator link. The packet dropouts are temporarily correlated in the sense that they obey a Markovian transition model. Our design task is to solve the optimal controller that minimizes a given receding horizon cost function, using the available packet loss history. Due to the correlated nature of the packet loss, standard linear quadratic regulator methods do not apply. We first present the optimal control law by considering the correlations. This controller turns out to depend on the packet loss history and would typically require a large lookup table for implementation when the Markovian order is high. To address this issue, we present and compare several suboptimal design approaches to reduce the number of control laws. 相似文献
88.
Damian Przestacki Mateusz Kukliński Aneta Bartkowska 《The International Journal of Advanced Manufacturing Technology》2017,93(9-12):3111-3123
In this study, a nickel-based superalloy, Waspaloy, was laser heat treated with diode laser. Single laser tracks were manufactured with different laser beam power densities between 63 and 331 kW/cm2, and scanning laser beam speed ranged from 5 to 100 m/min. It was found that laser heat treatment of Waspaloy causes decrease in material hardness—the microhardness in laser tracks is about 300 HV0,1 while the microhardness of substrate is ranged from 300 to 600 HV0,1—which is a positive phenomenon for laser-assisted machining of investigated material. Impacts of laser heat treatment parameters on laser tracks properties were identified for obtaining multiple laser tracks with the most homogenous thickness. Moreover, roughness of heated layers was measured to specify surface quality after laser heat treatment. Multiple laser tracks were produced using different scanning laser beam speed and distances between laser tracks ranged from 0.125 to 1 mm. It was found that if scanning laser beam speed is 75 m/min and distance between laser tracks is equal to or lower than 0.25 mm, in microstructures of multiple laser tracks, cracks are occurring. The most suitable laser heat parameters for obtaining heated layers, and which can be used for laser-assisted machining, were identified as laser beam power density 178.3 kW/cm2, scanning laser beam speed 5 m/min, and distance between laser tracks 0.125 mm. 相似文献
89.
Tooth eruption across the mucosa in humans has been studied rarely, although there are disturbances of eruption that are attributed specifically to failure of the supraosseous eruptive migration. The aim of this study was to analyze the soft tissues covering normally erupting teeth so as to get an insight into the supraosseous phase of tooth eruption and to provide the basis for comparison with cases of eruption disturbances. Six opercula covering normally erupting permanent molars (primary opercula) and six of succedaneous teeth (secondary opercula) were surgically removed from 10 patients aged 7.5-17.5 years. Specimens were examined light and electron microscopically and analyzed morphometrically. All opercula contained strands and islands of odontogenic epithelium, prominent numbers of high endothelial venules, nerves, and mast cells. Nerves comprised normally structured, 1.5-3.5 microm thick myelinated (Adelta) and thinner unmyelinated (C) fibers. In primary opercula, the proportions of blood vessels and nerves were three- and sevenfold higher than the respective values for the secondary opercula. Furthermore, primary opercula contained multinucleated, fibroblast-like giant cells that were not observed in secondary opercula. As all teeth under investigation were erupting normally, neither the presence of the giant cells nor the atypical proportions of blood vessels and nerves appeared to be decisive in the eruption process. These conspicuous tissue components of opercula seem merely to accompany the eruptive tooth movement. 相似文献
90.