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151.
An overview of nondestructive evaluation methods 总被引:1,自引:0,他引:1
Marvin Trimm 《Journal of Failure Analysis and Prevention》2003,3(3):17-31
ondestructive evaluation is described as nondestructive testing (NDT), nondestructive inspection (NDI), and nondestructive
examination (NDE). The activities associated with the evaluation include testing, inspection, and examination and primarily
involve looking at (or through) and/or measuring some characteristic of an object. Frequently there is a desire to determine
some characteristic of the object or to determine whether the object contains irregularities, discontinuities, or flaws. These
examinations, inspections, or tests are used to determine the physical soundness of a material without impairing its usefulness.
Nondestructive evaluation is a powerful tool that can help assure safety, quality, and reliability; increase productivity;
decrease liability; protect the environment; and save money. In this article, nondestructive evaluation is represented by
the acronym NDE. 相似文献
152.
Nguyen An Tien I. Ya. Mittova O. V. Almjasheva S. A. Kirillova V. V. Gusarov 《Glass Physics and Chemistry》2008,34(6):756-761
Nanocrystalline LaFeO3 is prepared by the dehydration of coprecipitated lanthanum and iron(III) hydroxides. It is shown that the behavior of the samples during heating and the size distribution of LaFeO3 nanocrystals can be considerably different depending on the scheme used for coprecipitation of lanthanum and iron hydroxides; independently of the method employed for coprecipitation of the initial compounds, sintering of the samples at 950°C leads to the formation of lanthanum orthoferrite crystals up to 100 nm in size. 相似文献
153.
Shinsook Yoon Mi-Kyoung Kim In-Young Lee Mikyung Yun Jeong E. Nam Shin 《Journal of Industrial and Engineering Chemistry》2008,14(6):759-764
We have developed a mutant strain derived from Agrobacterium sp. ATCC 31750, which produces a water-soluble polysaccharide having potential utility to the food, feed, pharmaceutical and cosmetic industries. A high concentration of product (15 g/L) is obtained by 48 h cultivation of the mutant strain under optimized fermentation conditions. The water-soluble polysaccharide obtained from cultures of the mutant strain beta82 has Glc:Man:Gal in approximate molar ratios of 5.8:6.7:1.0. The molecular weight of the polysaccharide was determined to be approximately 1000 kDa by HPSEC analysis. Linkage analysis contained 3-Glcp, 3-Manp, terminal Glcp and terminal Manp, as well as a small proportion of 3- and 3,4-Galp, and 4,6-Manp residues. Based on analyses using FT-IR and 13C NMR spectrometers, most glycosidic bonds joining these sugar residues are of the α-type, and acetyl groups are apparently attached to the polymer chain at random. 相似文献
154.
Injun Lee Taeseong Jung Junggi Kim Suho Ro Chulsu Kim Yeji Lee Youngmi Kim Juhyun Lee Misook Kang 《Journal of Industrial and Engineering Chemistry》2008,14(6):869-873
This study focuses on the relationship between photo-catalytic performance and optical property over Si-incorporated TiO2. The Si-incorporated TiO2 particles exhibited a pure structure of anatase having a particle size of less than 20 nm and surface area of more than 190 m2/g. The absorbance did not shift to a higher wavelength in spite of the incorporation of the Si ions, but the intensity of the photoluminescence (PL) curve was the smallest in the case of the 2.0 mol% Si-TiO2, which was related to the recombination between the excited electrons and holes. Based on these results, the photodecomposition of methyl orange in the liquid reaction was enhanced over the 2.0 mol% Si-incorporated TiO2 compared with that over pure TiO2: Methyl orange at 10.0 ppm was completely decomposed after 100 min when 1.0 g of the 2.0 mol% Si-incorporated TiO2 was used. 相似文献
155.
Vjacheslav V. Zuev 《Journal of Polymer Research》2008,15(5):351-356
Functionalized polyanilines containing biphenyl, terphenyl, carbazole, anthracene, and 4-n-hexylphenyl moieties were synthesized though the reaction of polyaniline in emeraldine base form with sodium salt of corresponding
vinylketoaromatics with quantitative yields. Polymers were characterized with Fourier transform infrared spectroscopy, proton
nuclear magnetic resonance spectroscopy, and thermogravimetry. The emission characteristics of these polymers in N-methyl-2-pyrrolidone solution were examined. The functionalized polyanilines exhibited an intense green emission. 相似文献
156.
We propose two new antidiffusive schemes for advection (or linear transport), one of them being a mixture of Roe’s Super-Bee
scheme and of the “Ultra-Bee” scheme. We show how to apply these schemes to treat time-dependent first order Hamilton–Jacobi–Bellman
equations with discontinuous initial data, possibly infinitely-valued. Numerical tests are proposed, in one and two space
dimensions, in order to validate the methods
AMS subject classifications. Primary 65M12, Secondary 58J47 相似文献
157.
Gokhan Tur 《Machine Learning》2007,69(1):55-74
We propose three methods for extending the Boosting family of classifiers motivated by the real-life problems we have encountered. First, we propose a semisupervised learning method for exploiting the unlabeled data in Boosting. We then present a novel classification model adaptation method. The goal of adaptation is optimizing an existing model for a new target application, which is similar to the previous one but may have different classes or class distributions. Finally, we present an efficient and effective cost-sensitive classification method that extends Boosting to allow for weighted classes. We evaluated these methods for call classification in the AT&;T VoiceTone® spoken language understanding system. Our results indicate that it is possible to obtain the same classification performance by using 30% less labeled data when the unlabeled data is utilized through semisupervised learning. Using model adaptation we can achieve the same classification accuracy using less than half of the labeled data from the new application. Finally, we present significant improvements in the “important” (i.e., higher weighted) classes without a significant loss in overall performance using the proposed cost-sensitive classification method. 相似文献
158.
Matthias Zobel Joachim Denzler Benno Heigl Elmar Nöth Dietrich Paulus Jochen Schmidt Georg Stemmer 《Machine Vision and Applications》2003,14(1):26-34
Abstract. This contribution introduces MOBSY, a fully integrated, autonomous mobile service robot system. It acts as an automatic dialogue-based
receptionist for visitors to our institute. MOBSY incorporates many techniques from different research areas into one working
stand-alone system. The techniques involved range from computer vision over speech understanding to classical robotics.
Along with the two main aspects of vision and speech, we also focus on the integration aspect, both on the methodological
and on the technical level. We describe the task and the techniques involved. Finally, we discuss the experiences that we
gained with MOBSY during a live performance at our institute. 相似文献
159.
The effects of key parameters on the preparation and regeneration of protoplast from the β-carotene-producing fungus Blakeslea trispora were discussed in this paper, including the combination of various enzymes, mycelial age, digesting time and temperature,
pH value, osmotic stabilizers, pretreatment, culture medium and culture method. Under the condition of mixed enzymes in osmotic
stabilizer (0.6 M NaCl) combined with 2% lysozyme, 3% cellulase and 3% snailase, the highest protoplast yield, as high as
7.48×106 protoplasts/mL, was obtained when mycelial age was 60 h at pH 5.0–6.0 with digesting for 14–16 h at 28 °C. After
purification of the obtained protoplasts, they were regenerated in PDA regenerative medium using bilayer plate culture method.
To validate the usability of the protoplasts, a novel plasmid with green fluorescent protein (GFP) was used in transformation
for easy visual observation. The results showed that the protoplasts prepared by the optimized method were active and applicable
in further gene manipulation experiments.
This work was presented at 13
th
YABEC symposium held at Seoul, Korea, October 20–22, 2007. 相似文献
160.
Min Chan Kim Dong Won Lee Chang Kyun Choi 《Korean Journal of Chemical Engineering》2008,25(6):1239-1244
When a horizontal homogeneous solid is melted from below, convection can be induced in a thermally unstable melt layer. In
this study the onset of buoyancy-driven convection during time-dependent melting is investigated by using similarly transformed
disturbance equations. The critical Rayleigh numbers based on the melt-layer thickness are found numerically for various conditions.
For small superheats, the present predictions approach the well known results of classical Rayleigh-Bénard problems, that
is, critical Rayleigh numbers are located between 1,296 and 1,708, regardless of the Prandtl number. However, for high superheats
the critical Rayleigh number increases with an increase in phase change rate but with decrease in Prandtl number. 相似文献