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121.
Reticulated vitreous carbon (RVC) foams were manufactured by multiple replications of a polyurethane foam template structure using ethanolic solutions of phenolic resin. The aims were to create an algorithm of fine tuning the precursor foam density and ensure an open-cell reticulated porous structure in a wide density range. The precursor foams were pyrolyzed in inert atmospheres at 700°C, 1100°C and 2000°C, and RVC foams with fully open cells and tunable bulk densities within 0.09–0.42 g/cm3 were synthesized. The foams were characterized in terms of porous structure, carbon lattice parameters, mechanical properties, thermal conductivity, electric conductivity, and corrosive resistance. The reported manufacturing approach is suitable for designing the foam microstructure, including the strut design with a graded microstructure.  相似文献   
122.
Food product safety is one of the most promising areas for the application of electronic noses. Their application in this domain is mainly focused on quality control, freshness evaluation, shelf-life analysis and authenticity assessment. In this paper, the performance of a portable electronic nose has been evaluated in monitoring the spoilage of beef fillets stored either aerobically or under modified atmosphere packaging, at different storage temperatures. A novel multi-output fuzzy wavelet neural network architecture has been developed, which incorporates a clustering pre-processing stage for the definition of fuzzy rules. The dual purpose of the proposed modelling approach is not only to classify beef samples in the relevant quality class (i.e. fresh, semi-fresh and spoiled), but also to predict their associated microbiological population, based on total viable counts. For the case of aerobic packaging, model was able to classify correctly 67 out of 70 aerobic samples (95.71%), while successful identification of microbial counts resulted in a 4.57% standard error of prediction. However, under modified atmosphere packaging scenario, results were rather inferior, as proposed model achieved a 92.95% classification rate (66 out of 71 samples), while the standard error of prediction of microbial counts was increased to 5.74%. In comparison to these results, prediction performances of models used extensively in the area of Food Microbiology, such as MLP and PLS, revealed their deficiencies, while ANFIS and SVM models revealed their robustness in providing acceptable prediction performances for either aerobic or MAP packaging conditions. Results evaluation indicated that the proposed modelling scheme could be considered as a valuable detection methodology in food microbiology.  相似文献   
123.
In many network management applications, likepost-mortem fault analysis or performance trendsprofiling, it is advantageous to have the ability toview the state of the network as it was at some time in the past. To support such Temporal Views anefficient data organization, or access method, is neededfor storing and updating network related data (as thenetwork evolves over time) and for retrieving requested past network states. For applications where thenetwork manager is not interested in the full (and maybetoo large) snapshot of a past network state it is usefulif partial state snapshots can be extracted quickly. It is thus of particular interest toconstruct an access method that can efficiently supportPartial Temporal Views. Efficiency implies that arequested partial temporal view should be constructed directly, without first computing the elaboratefull temporal view. In this paper we present a newaccess method (called the Neighbor History Index) forthis problem. One of the advantages of this method is that the update processing is independent ofthe evolution size (the total number of changes in theevolution). In addition, our method uses a small diskspace overhead. We then present a general framework for organizing time-evolving network data. Ourframework distinguishes between flat and hierarchicalevolutions and subsequently between flat andhierarchical temporal views. We also provide a way toefficiently construct temporal views on hierarchicalevolutions. This paper shows that supporting temporalviews on flat or hierarchical evolutions is notexpensive: our solutions use small space overhead, havesmall updating and compute temporal viewsfast.  相似文献   
124.
中国建筑学会本次年会关注建筑与我们这个星球的和谐关系,这不是一个巧合.它表明中国建筑师为建立这种和谐关系做出贡献的决心.同样,国际建协主席加埃唐·修和副主席路易斯·考克斯同时出席本次会议也不是一个巧合.  相似文献   
125.
Mitochondria are key organelles that combine features inherited from their bacterial endosymbiotic ancestor with traits that arose during eukaryote evolution. These energy producing organelles have retained a genome and fully functional gene expression machineries including specific ribosomes. Recent advances in cryo-electron microscopy have enabled the characterization of a fast-growing number of the low abundant membrane-bound mitochondrial ribosomes. Surprisingly, mitoribosomes were found to be extremely diverse both in terms of structure and composition. Still, all of them drastically increased their number of ribosomal proteins. Interestingly, among the more than 130 novel ribosomal proteins identified to date in mitochondria, most of them are composed of a-helices. Many of them belong to the nuclear encoded super family of helical repeat proteins. Here we review the diversity of functions and the mode of action held by the novel mitoribosome proteins and discuss why these proteins that share similar helical folds were independently recruited by mitoribosomes during evolution in independent eukaryote clades.  相似文献   
126.
127.
In this paper, an ontology-based system (KnowBaSICS-M) is presented for the semantic management of Medical Computational Problems (MCPs), i.e., medical problems and computerised algorithmic solutions. The system provides an open environment, which: (1) allows clinicians and researchers to retrieve potential algorithmic solutions pertinent to a medical problem and (2) enables incorporation of new MCPs into its underlying Knowledge Base (KB). KnowBaSICS-M is a modular system for MCP acquisition and discovery that relies on an innovative ontology-based model incorporating concepts from the Unified Medical Language System (UMLS). Information retrieval (IR) is based on an ontology-based Vector Space Model (VSM) that estimates the similarity among user-defined MCP search criteria and registered MCP solutions in the KB. The results of a preliminary evaluation and specific examples of use are presented to illustrate the benefits of the system. KnowBaSICS-M constitutes an approach towards the construction of an integrated and manageable MCP repository for the biomedical research community.  相似文献   
128.
129.
Metastases to the bone are presenting in a great percentage of patients with cancer, causing a variety of symptoms, affecting the quality of life and survival of patients. A multidisciplinary approach from different health providers is required for treatment, including radiation oncologists, medical oncologists and surgeons. The role of radiotherapy in the management of bone metastases has long been established through multiple randomized trials. The estimation of response to the therapy is subjective and is based on the palliation of the symptoms that the patients report. However, a quantification of the tumor burden and response to the treatment with the use of an objective method to measure those parameters is a clinical expectation in oncology. The change in bone density in affected areas (mainly lytic) after local radiotherapy, representing the cellular changes that have occurred, is a promising marker of response to treatment.  相似文献   
130.
The article investigates the relationship between attitudes towards evidence-based practice (EBP) and the use of information and communication technology (ICT) in practice and demonstrates that the poor correlation reported in the literature is a methodological artifact rather than a substantive fact. Results are based on structured surveying of 1015 medical and nursing staff, drawn from 15 Greek hospitals. We used unfolding item response theory models to demonstrate that by placing the statements assessing attitude towards EBP and ICT self-reported use on a single attitude–behaviour continuum, behaviour statements have a systematically different location on the attitude–behaviour continuum from the attitude statements. Based on the latent probabilistic relation among attitudes towards EBP and ICT use, the practical implications of the study are discussed.  相似文献   
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