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11.
Hemant Ramaswami Atul Modi Sam Anand 《The International Journal of Advanced Manufacturing Technology》2007,31(9-10):857-870
In the wake of growing importance for quality and the need to reduce inspection costs simultaneously, the need for a scientific method of selecting an optimum inspection strategy for coordinate measuring machine (CMM) based inspection has become very important. The inspection error resulting from CMM inspection is greatly affected by the profile irregularities and the sampling strategy, which includes sample size, sampling methods, and algorithms used for form evaluation. This paper describes a system that can recommend an optimal inspection plan based on the needs of the user. A design of experiments (DOE) based approach is used to relate the inspection error with sampling strategies. Surface irregularities are included in the form of lobes formed on the profile. A new two-way model is proposed that works in both directions between the sampling strategy and the performance metrics. The results indicate that the number of lobes and the sampling method used have little impact on the inspection error, while the sample size and form evaluation algorithms have a significant influence. An inspection plan advisor is presented, which provides an inspection plan based on the estimated shape and acceptable measurement error. 相似文献
12.
The geochemical behavior of U, Th series nuclides in surface marine sediments collected fromthe Red Sea coastal environment of Sudan was examined using daughter/parent and nonisotopic activity ratios. Pronounced anomalous behavior of several series of nuclides has been observed, particularly at shallower depths. On the average, the 234U/238U ratio is fairly constant and close to 1.13, suggesting scavenging of 234U from the overlying water column. In shallow-water sediments collected from the biologically productive area of the fringing reef and from the tidal-flat of Sanganeb atoll, compared to harbor and deep-sea sediments, 238U was found in large excess relative to 232Th. The 228Th/232Th disequilibrium indicates rapid sedimentation at shallower sites, which agrees well with data reported in the literature for similar environments. Depletion was observed of precursor thorium isotopes (230Th, 232Th) with respect to their mobile daughter isotopes of radium (226Ra, 228Ra). On the other hand, there is surface enrichment of 228Th and 210Po with respect to their progenitors 228Ra and 226Ra, as demonstrated by the 228Th : 228Ra and 210Po : 226Ra activity ratio, which is greater than unity in all the sediments analyzed. The 210Po/226Ra ratio is fairly constant (average 3.2). 相似文献
13.
The rate of filtration and the water content of cake are influenced by the existence of a dense skin in a highly compressible
cake. The phenomenon of the dense skin has been rarely studied, and its existence has not been verified experimentally. In
this study, the porosity variation in a very compressible cake is measured by using a new experimental apparatus, and with
this the existence of dense skin has been established experimentally. ‘Unified theory on solid-liquid separation’, a recently
developed theory, is utilized for calculating the porosity variation in a very compressible cake. 相似文献
14.
F. H. Sam Froes 《Powder Metallurgy and Metal Ceramics》2007,46(5-6):303-310
The approaches to production of titanium powder injection molded parts are reviewed. Historically, oxygen levels have been
too high for structural use (particularly with the Ti-6Al-4V alloy). However, recent advances in starting powders, binders
and sintering facilities now allow oxygen levels in the Ti-6Al-4V alloy to be controlled to about 0.2 wt.% oxygen. This should
result in significant expansion of the titanium PIM market place into aerospace, automobiles, surgical instruments, dentistry,
communication devices (such as computers and cell phones), knives and guns.
__________
Translated from Poroshkovaya Metallurgiya, Vol. 46, No. 5–6 (455), pp. 118–125, 2007. 相似文献
15.
BM King JT Cook KN Rossiter LM Theobold H Sam 《Canadian Metallurgical Quarterly》1996,60(6):1569-1571
Bilateral lesions in the most posterodorsal aspects of the amygdala in female rats resulted in immediate and dramatic weight gains on a standard lab chow diet. The rate of weight gain returned to normal by Day 20, but the difference in body weight between animals with amygdaloid lesions and those with sham lesions was maintained for the duration of the study (60 days). Because rats with posterodorsal amygdaloid lesions have also been found to be hyperinsulinemic, it is hypothesized that the lesions result in a similar, though smaller, version of the syndrome that follows lesions of the ventromedial hypothalamus. 相似文献
16.
R. Sam Williams Steve Lacher Corey Halpin Christopher White 《Materials and Structures》1988,21(4):313-320
RILEM Bulletin
Fourth International Conference on Durability of Building Materials and Components 相似文献17.
Railway Engineering Science - Electrified railways are becoming a popular transport medium and these consume a large amount of electrical energy. Environmental concerns demand reduction in energy... 相似文献
18.
Jin-Xian Liao Yu-Wei Chen Ming-Kuei Shih You-Lin Tain Yao-Tsung Yeh Min-Hsi Chiu Sam K. C. Chang Chih-Yao Hou 《International journal of molecular sciences》2021,22(10)
Resveratrol can affect the physiology or biochemistry of offspring in the maternal–fetal animal model. However, it exhibits low bioavailability in humans and animals. Fifteen-week SD pregnant female rats were orally administered bisphenol A (BPA) and/or resveratrol butyrate ester (RBE), and the male offspring rats (n = 4–8 per group) were evaluated. The results show that RBE treatment (BPA + R30) compared with the BPA group can reduce the damage caused by BPA (p < 0.05). RBE enhanced the expression of selected genes and induced extramedullary hematopoiesis and mononuclear cell infiltration. RBE increased the abundance of S24-7 and Adlercreutzia in the intestines of the male offspring rats, as well as the concentrations of short-chain fatty acids (SCFAs) in the feces. RBE also increased the antioxidant capacity of the liver by inducing Nrf2, promoting the expression of HO-1, SOD, and CAT. It also increased the concentration of intestinal SCFAs, enhancing the barrier formed by intestinal cells, thereby preventing BPA-induced metabolic disruption in the male offspring rats, and reduced liver inflammation. This study identified a potential mechanism underlying the protective effects of RBE against the liver damage caused by BPA exposure during the peri-pregnancy period, and the influence of the gut microbiota on the gut–liver axis in the offspring. 相似文献
19.
Rubber‐toughened poly(trimethylene terephthalate) (PTT)–organoclay nanocomposite (RTPTTCN) was prepared by a melt mixing technique. The rubber‐toughened PTT (RTPTT) was made by blending it with ethylene propylene diene terpolymer (EPDM) and with a small amount of maleated EPDM as a compatibilizer. XRD and TEM analysis indicated that the RTPTTCN forms a partially exfoliated nanocomposite. It was observed from SEM analysis that the clay nanoparticles induced a reduction of rubber particle size in the PTT matrix. Tensile and dynamic mechanical analysis indicated that the clay nanoparticles enhance the stiffness of the RTPTT without adversely affecting its toughness. Melt rheological studies revealed that the nanocomposites exhibited strong shear thinning behavior, and a percolated network of the clay particles was formed. It was also observed from DSC that the clay nanoparticles caused an increase in the nonisothermal crystallization temperature of the PTT. POLYM. ENG. SCI., 47:863–870, 2007. © 2007 Society of Plastics Engineers 相似文献
20.
In this paper, robust adaptive control is developed for a thruster assisted position mooring system in the transverse direction. To provide an accurate and concise representation for the dynamic behavior of the mooring system, the flexible mooring lines are modeled as a distributed parameter system of partial differential equations (PDEs). The proposed control is applied at the top boundary of the mooring lines for station keeping via Lyapunov’s direct method. Adaptive control is designed to handle the system parametric uncertainties. With the proposed robust adaptive control, uniform boundedness of the system under the ocean current disturbance is achieved. The proposed control is implementable with actual instrumentations since all the signals in the control can be measured by sensors or calculated by using a backward difference algorithm. The effectiveness of the proposed control is verified by numerical simulations. 相似文献