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71.
Daniel N. Farhey Razi Naghavi Alper Levi Aniruddha M. Thakur Mark A. Pickett Douglas K. Nims A. Emin Aktan 《Canadian Metallurgical Quarterly》2000,5(1):39-48
Diagnostic truck-load tests and microstructural analysis were applied for structural deterioration assessment of a steel truss bridge and its rehabilitation design. The feasibility and potential benefits of using advanced field experimental techniques within a structural-identification framework have been demonstrated. Experimental information, coupled with visual inspection, engineering experience, and intuition, increased the level of confidence in the results of the condition-assessment process, permitting a more rational and cost-effective rehabilitation design. Based on the condition assessment, a two-step rehabilitation is recommended for the bridge: Restoration for a safe service life of 5–7 years, and a subsequent effort for preservation beyond. 相似文献
72.
A simulated annealing algorithm for multi-agent systems: a job-shop scheduling application 总被引:4,自引:1,他引:4
In this paper, a parallel implementation of the modular simulated annealing algorithm for classical job-shop scheduling is presented. The implementation is for a multi agent system running on the distributed resource machine, which is a novel, scalable, distributed virtual machine based on Java technology. The problems tackled are well known, difficult benchmarks, widely used to measure the efficiency of metaheuristics with respect to both the quality of the solutions and the central processing unit time. The empirical results obtained show that the method proposed is successful in comparison with a sequential version of modular simulated annealing algorithm and other methods described in the literature. 相似文献
73.
In this study, for the first time, the effect of Nickel (Ni) additive on Magnesium oxide (MgO) thin films produced by using successive ionic layer adsorption and reaction technique (SILAR) was investigated. Absorption, photoluminescence (PL), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and scanning electron microscope (SEM) measurements were executed to examine how the optical, structural and morphological properties of the samples were affected by the addition of Ni. In the absorption analysis, it was noted that the band gaps of the MgO samples decreased from 4 eV to 3.5 eV with the increase of Ni dopant concentrations. Also, the transmittance values of MgO nanostructures decreases with the increase of Ni contribution, and in the same way, the reflection measurements show that the reflection of MgO decreases with the increase of Ni doping. PL measurements revealed that the fabricated structures radiate around 410 nm and 730 nm. According to XRD measurements, besides the cubic structure of the samples, NiO formations were detected inside the MgO thin film samples due to the increase in Ni dopant. XPS measurements have proven the presence of Ni doping in MgO. SEM measurements showed that all samples exhibited nanowall structure. All these results demonstrate that Ni doping on MgO thin films can be achieved by using SILAR deposition technique. 相似文献
74.
Muhammet Emre Turan Yavuz Sun Yasin Akgul 《Fullerenes, Nanotubes and Carbon Nanostructures》2018,26(2):130-136
The present study aims to fabricate fullerene (C60) reinforced magnesium matrix composite via semi powder metallurgy in hot press system under high purity argon atmosphere. Improvement of wear resistance of pure magnesium with the addition of fullerene is also aimed with this study. Hardness and wear tests at room temperature were performed to investigate the mechanical effect of fullerene nanoparticles. Microstructures of fabricated composites were characterized using Scanning Electron Microscope (SEM). Results clearly show that hardness performance was improved up to 0.5 wt. % fullerene addition directly. A uniform distribution was also achieved according to the mapping and line EDX analysis for the lower content of fullerene. Agglomeration of fullerene was observed for 1 wt. % reinforced composite. Wear performances of pure magnesium were also improved when harder fullerene reinforcements incorporated into the matrix. Abrasion and oxidation were main wear mechanism for unreinforced and fullerene reinforced composites. Enhancement of hardness and wear performances might be attributed to the high specific surface area of fullerene and achievement of uniform distribution of reinforcement in magnesium matrix. 相似文献
75.
d -Allulose (a monosaccharide and C3 epimer of fructose), one of the common rare sugars is getting attention due to its low caloric values. In this study, d -Allulose was used as a replacement of sucrose at different ratios (d -Allulose/Sucrose: 35/0, 20/15, 10/25, 0/35) to formulate pectin-based soft confectionery gels. Soy protein isolate was also added to increase the protein content. Physical properties, such as hardness, moisture content, pH, and color, were measured for the gels. Higher hardness values were obtained for the soy protein containing gels due to pectin–soy protein interaction (p < 0.05). Also, higher moisture content was observed in soy protein containing gels (p < 0.05). In addition, nuclear magnetic resonance T2 relaxation times were measured at low field (~0.5 T) to determine how the water distribution in the samples changed and to observe how d -Allulose affected the polymer–water interactions. The study also showed that the presence of d -Allulose increased the crystallization tendency (% crystallinity of 7.9) of the pectin gels. X-ray diffraction results showed the d -allulose peaks at 33.76 and 48.68oθ. Morphologies of the gels were also examined by scanning electron microscope. Sugar type and soy protein isolate addition were found to have significant impact on the gel formulations. 相似文献
76.
Bulletin of Engineering Geology and the Environment - A Correction to this paper has been published: https://doi.org/10.1007/s10064-021-02153-1 相似文献
77.
78.
Seniha Micoogullari Kurt Mehmet Emin Kaval Burcu Serefoglu Gzde Kandemir Demirci Mehmet Kemal alkan 《Microscopy research and technique》2020,83(7):790-794
The aim of this study was to evaluate the cyclic fatigue resistance of Dia‐X, WaveOne Gold and One Curve files in a water bath at intracanal temperature (35°C). Thirty‐nine instruments Dia‐X, WaveOne Gold, and One Curve systems (n = 13) were tested in an artificial canal with a curvature angle of 60° and a radius of 3 mm. A water bath setup at a temperature of 35°C was used to simulate the intracanal temperature and time to fracture (TTF) as seconds was recorded. The mean data were analyzed statistically using one‐way ANOVA, and post hoc Tukey test (p = .05). The fractured surface of the instruments was examined with scanning electron microscopy (SEM) and chemical composition of the instruments were investigated with energy dispersive X‐ray spectroscopy (EDS). Statistically significant differences were detected in TTF values of all the systems as follows: One Curve > WaveOne Gold > Dia‐X (p < .05). One Curve instruments demonstrated the highest TTF values in all the tested instruments. The EDS microanalysis revealed similar NiTi composition of on the surface of One Curve, WaveOne Gold, and Dia‐X instruments. The novel manufacturing process, including C‐wire heat treatment and the variable cross‐section of the One Curve files, could be the main factors affecting the fatigue life of the instruments. 相似文献
79.
80.