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The analysis of circular concrete columns using unconfined concrete models is a well established practice. However, there is a necessity to develop realistic analysis and design tools that predict the extreme ultimate capacity of such columns since modern codes and standards like AASHTO LRFD are introducing extreme load events. The increase in strength and ductility due to full axial confinement is not applicable to pure bending and bending plus axial load simply because the area of effective confined concrete is reduced. The higher the eccentricity the smaller the compressed portion of the confined core. Accordingly, the ultimate confined strength is gradually reduced from the fully confined value fcc′ (at zero eccentricity) to the unconfined value fc (at infinite eccentricity) as a function of eccentricity to diameter ratio. A numerical analysis algorithm is developed using the finite layer procedure and the secant stiffness approach within a framework of incremental-iterative moment of area computations. The resulting nonlinear section analysis requires radial loading in which the eccentricity is kept constant or the axial load is proportional to the applied moment. The results are compared with existing experimental data and the widely used Mander model to benchmark the present predictions.  相似文献   
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Sentiment analysis concerns the study of opinions expressed in a text. This paper presents the QMOS method, which employs a combination of sentiment analysis and summarization approaches. It is a lexicon-based method to query-based multi-documents summarization of opinion expressed in reviews.QMOS combines multiple sentiment dictionaries to improve word coverage limit of the individual lexicon. A major problem for a dictionary-based approach is the semantic gap between the prior polarity of a word presented by a lexicon and the word polarity in a specific context. This is due to the fact that, the polarity of a word depends on the context in which it is being used. Furthermore, the type of a sentence can also affect the performance of a sentiment analysis approach. Therefore, to tackle the aforementioned challenges, QMOS integrates multiple strategies to adjust word prior sentiment orientation while also considers the type of sentence. QMOS also employs the Semantic Sentiment Approach to determine the sentiment score of a word if it is not included in a sentiment lexicon.On the other hand, the most of the existing methods fail to distinguish the meaning of a review sentence and user's query when both of them share the similar bag-of-words; hence there is often a conflict between the extracted opinionated sentences and users’ needs. However, the summarization phase of QMOS is able to avoid extracting a review sentence whose similarity with the user's query is high but whose meaning is different. The method also employs the greedy algorithm and query expansion approach to reduce redundancy and bridge the lexical gaps for similar contexts that are expressed using different wording, respectively. Our experiment shows that the QMOS method can significantly improve the performance and make QMOS comparable to other existing methods.  相似文献   
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R-plasmids that transfer antibiotic resistance are common in the non-pathogenicEscherichia coli of the gastro-intestinal tract of human beings and domestic animals, which inturn may enter into sewage. Therefore we have isolated 30Escherichia coli isolates from hospital sewage of Aligarh city. These isolates were tested for their resistance and sensitivity against 10 antibiotics. 90% isolates showed resistance against ampicillin and sulphamethizole. Of the total 30E. coli isolates 86.6% were resistant to erythromycin and rifampicin but none of them was resistant to kanamycin and streptomycin. Plasmids (mol. wt. 16.5 mega daltons) were isolated from five differentE. coli strains which harboured only a single plasmid and were characterized on the basis of antibiogram. Moreover, the transformation experiments were also performed to confirm the resistant character on the plasmid. We conclude that multiple drug resistance among most of theE. coli isolates is plasmid borne.  相似文献   
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