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21.
In this paper, an element recently developed by Whitcomb (Comput. Struct. 22, 387–398, 1986) along the lines of the so-called substitute shape function technique (SSFT) has been re-examined. It is shown that a varialional basis can be found for this element in the form of a modified version of the variational theorem due to Hellinger and Reissner. On the basis of this theorem, a two-dimensional element has been developed using separate trial functions for the displacements and the shear strain. The element is identical to Whitcomb's element; however, the proposed approach appears to have certain advantages over SSFT. 相似文献
22.
Raja S.R.Gajjela Arthur L.Hendriks James O.Douglas Elisa M.Sala Petr Steindl Petr Klenovsky Paul A.J.Bagot Michael P.Moody Dieter Bimberg Paul M.Koenraad 《光:科学与应用(英文版)》2021,10(7):1313-1325
We investigated metal-organic vapor phase epitaxy grown (InGa)(AsSb)/GaAs/GaP Stranski–Krastanov quantum dots (QDs) with potential applications in QD-Flash memo... 相似文献
23.
Primary liver cancer is a heterogeneous disease. Liver cancer metabolism includes both the reprogramming of intracellular metabolism to enable cancer cells to proliferate inappropriately and adapt to the tumor microenvironment and fluctuations in regular tissue metabolism. Currently, metabolomics and metabolite profiling in liver cirrhosis, liver cancer, and hepatocellular carcinoma (HCC) have been in the spotlight in terms of cancer diagnosis, monitoring, and therapy. Metabolomics is the global analysis of small molecules, chemicals, and metabolites. Metabolomics technologies can provide critical information about the liver cancer state. Here, we review how liver cirrhosis, liver cancer, and HCC therapies interact with metabolism at the cellular and systemic levels. An overview of liver metabolomics is provided, with a focus on currently available technologies and how they have been used in clinical and translational research. We also list scalable methods, including chemometrics, followed by pathway processing in liver cancer. We conclude that important drivers of metabolomics science and scientific technologies are novel therapeutic tools and liver cancer biomarker analysis. 相似文献
24.
Abdul Qadir Shah Tasneem Gul Kazi Muhammad Balal Arain Muhammad Khan Jamali Hassan Imran Afridi Nusrat Jalbani Ghulam Abbas kandhro Jameel Ahmed Baig Raja Adil sarfraz Rehana ansari 《Food chemistry》2009
The purpose of this study was to estimate total arsenic concentration in different tissues (leg, breast, liver and heart) of broiler chicken by hydride generation atomic absorption spectrometry (HGAAS) and graphite furnace atomic absorption spectrometry (GFAAS), prior to microwave assisted acid digestion. The accuracy of the techniques was evaluated by using certified reference material DORM-2. The percentage recoveries of total As were observed as 100.6% and 99.4% for HGAAS and GFAAS, respectively. The precision of the techniques, expressed as relative standard deviation, was observed as 1.71% and 4.18% for HGAAS and GFAAS measurements, respectively. The limits of detection for HGAAS and GFAAS were 0.025 μg/g and 0.052 μg/g, respectively. The concentrations of total arsenic in different tissues of broiler chicken were found in the range of 2.19–5.28, 2.15–5.22, 2.97–7.17 and 2.68–6.36 μg/g for leg, breast, liver and heart tissues, respectively. At a mean level of chicken consumption (60 g/person/day), people may ingest in the range of 72.0–85.1 μg arsenic/person/day from chicken alone. 相似文献
25.
Raja Fawad Zafar Michael B. C. Khoo Sajal Saha Zhi Lin Chong 《Quality and Reliability Engineering International》2021,37(6):2329-2333
The progressive mean (PM) statistic is based on a simple idea of accumulating information of each subgroup by calculating the average progressively. Its weighting structure is based on a subgroup number that changes arithmetically, which makes the PM chart unique and efficient compared with the existing classical memory control charts. In a recent article (see reference 1), it was claimed that the PM chart is a special case of the exponentially weighted moving average (EMWA) chart. In this article, it is shown that even though the PM statistic can be written in the form of an EWMA statistic, the variance of the PM statistic is different from that of the EWMA statistic. Consequently, the limits of the PM chart are different from that of the EWMA chart. Therefore, it is found that the PM chart is not a special case of the EWMA chart; hence, the claim in reference 1 is incorrect. Furthermore, it is pointed out in this paper that no adaptive property in the weighting parameter of the PM statistic exists, further contradicting the claim in reference 1. 相似文献
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27.
Image denoising is a procedure aimed at removing noise from images while retaining as many important signal features as possible. Many images suffer from poor contrast due to inadequate illumination or finite sensitivity of the imaging device, electronic sensor noise or atmospheric disturbances. This paper proposes a hybrid directional lifting technique for image denoising to retain the original information present in the images. The primary objective of this paper is to show the impact of applying preprocessing techniques for improving classification accuracy. In order to classify the image accurately, effective preservation of edges and contour details of an image is essential. The discrete wavelet transform-based interpolation technique is developed for resolution enhancement. The image is then classified using support vector machine classifier, which is well suitable for image classification. The efficiency of the classifier is analyzed based on receiver operating characteristic (ROC) curves. The quantitative performance measures peak signal to noise ratio and ROC analysis show the significance of the proposed techniques. 相似文献
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29.
Silk electrogelation involves the transition of an aqueous silk fibroin solution to a gel state (E-gel) in the presence of an electric current. The process is based on local pH changes as a result of water electrolysis - generating H(+) and OH(-) ions at the (+) and (-) electrodes, respectively. Silk fibroin has a pI=4.2 and when local pH相似文献
30.
Vemal Raja Manikam Khairunisak Abdul Razak Kuan Yew Cheong 《Journal of Materials Science: Materials in Electronics》2013,24(8):2678-2688
An Ag–Al die attach material having a fixed Ag–Al nanoparticles weight percent content (80–20 %), as well as varying organic additives weight percent content was formulated. The total nanoparticle weight percent content was varied between 84.7 and 87.0 %. As the organic additives content in the Ag80–Al20 die attach material decreased from 15.3 to 13.0 %, the nanopaste’s viscosity increased. The die attach material was sintered at 380 °C for 30 min to form Ag2Al and Ag3Al compounds. With decreasing organics content from 15.3 to 13.0 %, the porosity of the post-sintered samples also decreased from 30 to 19 %, while the density increased from 2.36 to 6.42 g/cm3. The highest melting point was recorded for the sample with the least organic weight percent content at 519 °C. The coefficient of thermal expansion and electrical conductivity values varied between 6.99–7.74 × 10?6/ °C and 0.95–1.01 × 105 (ohm-cm)?1 respectively with decreasing organic content from 15.3 to 13.0 %. The electrical conductivity values recorded were higher than or equal to that of most solder alloy die attach materials. By changing the organic additives content in the Ag80–Al20 die attach material, suitable properties are obtained for high temperature die attach applications. 相似文献