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991.
The recently concluded OECD SETH project included twenty-four experiments on basic flows and gas transport and mixing driven by jets and plumes in two, large, connected vessels of the PANDA facility. The experiments featured injection of saturated or superheated steam, or a mixture of steam and helium in one vessel and venting from the same vessel or from the connected one. These tests have been especially designed for providing an extensive data base for the assessment of three-dimensional codes, including CFD codes. In particular, one of the goals of the analytical activities associated with the experiments was to evaluate the detail of the model (mesh) necessary for capturing the various phenomena. This work reports an overview of the results obtained for these experimental data using the advanced containment code GOTHIC and relatively coarse meshes, which are coarser than the ones typically used for the simulation with commercial CFD codes, but are still representative of the models which are currently affordable for a full containment analysis. In general, the phenomena were correctly represented in the simulations with GOTHIC, and the agreement of the results with the data was in most cases pretty good, in some cases excellent. Only for a few tests (or particular phenomena occurring in some tests) the simulations showed noticeable discrepancies with the experimental data, which could be referred to either an insufficiently detailed mesh or to lack of specialized models for local effects.  相似文献   
992.
Text Mining Techniques to Automatically Enrich a Domain Ontology   总被引:3,自引:0,他引:3  
Though the utility of domain ontologies is now widely acknowledged in the IT (Information Technology) community, several barriers must be overcome before ontologies become practical and useful tools. A critical issue is the ontology construction, i.e., the task of identifying, defining, and entering the concept definitions. In case of large and complex application domains this task can be lengthy, costly, and controversial (since different persons may have different points of view about the same concept). To reduce time, cost (and, sometimes, harsh discussions) it is highly advisable to refer, in constructing or updating an ontology, to the documents available in the field. Text mining tools may be of great help in this task. The work presented in this paper illustrates the guidelines of SymOntos, ontology management system, and the text mining approach adopted herein to support ontology building. The latter operates by extracting, from the related literature, the prominent domain concepts and the semantic relations among them.  相似文献   
993.
Multimedia Tools and Applications -  相似文献   
994.
Efficient collaborative product design is crucial for extended enterprises willing to develop complex products pursuing a short time to market. However, successful collaborative product design depends on the ability to effectively manage and share engineering knowledge and data throughout the entire product development process. Co-design software platforms aim to facilitate cooperation in distributed teams. In the context of Small and Medium Enterprises (SMEs) the advanced co-design software implementation to support the supply chain is not a trivial task. SMEs have peculiar characteristics such as flexibility, ICT skills and financial resources, which are difficult to be integrated within a structured design network. This paper presents a method to define and evaluate a co-design platform dedicated to SMEs in the mechanical product field. System architecture is defined by applying suitable metrics based on collaborative process characteristics in order to assess functionality performance of the available tools. Benchmarking is based on different levels of collaboration recognized in the typical product development process in SMEs. Correlation between process metrics, software functionalities and specific collaboration requirements is managed by adopting Quality Function Deployment (QFD) techniques. A practical case study allows the robustness of the proposed method to be verified and the main advantages and future developments to be discussed.  相似文献   
995.
Michele Sbacchi examines the impact of the discipline of Euclidean geometry upon architecture and, more specifically, upon theory of architecture. Special attention is given to the work of Guarino Guarini, the seventeenth century Italian architect and mathematician who, more than any other architect, was involved in Euclidean geometry. Furthermore, the analysis shows how, within the realm of architecture, a complementary opposition can be traced between what is called “Pythagorean numerology” and “Euclidean geometry”. These two disciplines epitomized two overlapping ways of conceiving architectural design.  相似文献   
996.
Most of the recently proposed text entry methods for touch screen devices are stroke-based: the traditional tapping interaction is being replaced with a more natural gesture, performed through a pointer (pen or finger) on a soft keyboard. These methods need an effective technique to interpret user strokes, in order to correctly obtain the text the user intends to enter. KeyScretch is a recent text entry method based on menu-augmented soft keyboards. The method introduces a new way of interacting with radial menus through compound strokes. In this paper we present the technology used for recognizing these strokes. In particular, the design of different recognizers is presented and their performances are compared. The evaluation shows that geometric stroke recognition techniques, associated to other calibrations, can significantly improve the accuracy achievable using a simple target-based method.  相似文献   
997.
Analytical solutions for the J-integral and the strain energy density (SED) averaged over a control volume are presented for U- and blunt V-shaped notches under torsion. The influence of the notch tip radius and the notch opening angle are fully included in the new proposed relationships. These expressions take advantage of some recent solutions for the stress fields ahead of blunt notches under Mode III loading and can be seen as a synthesis of the efforts carried out during the last years by the present authors on this topic. Afterwards, the expressions are applied to a recent set of experimental data from cracked, notched and plain specimens tested under torsion at low temperature \((-60\,^{\circ }\hbox {C})\) . The large scatter shown by notched specimens in terms of maximum elastic stresses strongly reduces when the J-integral or the local SED are used in combination with the specific control volumes.  相似文献   
998.
999.
DRESS/DiHS is a complex and potentially fatal drug reaction. Little is known about risk factors and elements that can help to identify patients with a severe reaction early. The aim of the study was to investigate those factors favoring the disease and its severity by analyzing the clinical conditions and therapies preceding the reaction. We conducted a retrospective analysis on patients admitted to our center between 2010 and 2020 who were discharged with a diagnosis of DRESS. We used the RegiSCAR diagnostic criteria. We defined the severity of DRESS using the criteria of Mizukawa et al. We included 25 patients (15 females) with a median age of 66 years. Skin involvement, eosinophilia, and liver injury were the most important aspects. Allopurinol was found to be the most involved drug. Reaction severity was significantly associated with the number of daily medications (p = 0.0067) and an age of at least 68 years (p = 0.013). In addition, 75% of severe cases had at least three comorbidities in history, and most of the severe cases were female. In our study the advanced age, the high number of comorbidities and home therapies, and the inflammatory state were found to be predisposing elements to the development of the disease and its severity.  相似文献   
1000.
A joint multiagency project was initiated in response to a Salmonella outbreak in San Diego County, California, in 2004. Samples of cheese were collected during four 1-day operations at the San Ysidro port of entry, along the United States-Mexico border. Surveyed participants were persons crossing the border as pedestrians or in vehicles who had a minimum of 2.27 kg of cheese, which may suggest a potential diversion to illegal marketing. In addition, data were collected about the cheese to identify risk factors for cheese contamination. Two hundred four cheese samples were submitted to the California Animal Health and Food Safety Laboratory System-San Bernardino Branch and analyzed for potential food pathogens. Ninety-four percent (190 of 203) of the samples tested positive for alkaline phosphatase. Salmonella was detected from 13% (27 of 204) of the samples comprising 11 serogroups and 28 serotypes. Pulsed-field gel electrophoresis DNA fingerprinting analysis, performed following standardized methods, determined that an isolate obtained from this study had an indistinguishable pattern from a recent Salmonella enterica serovar Typhimurium var. Copenhagen epidemic in the San Diego County that was linked to 14 illnesses. Listeria spp. were detected from 4% (8 of 204) of the samples, and of these, half were identified as L. monocytogenes. Escherichia coli O157:H7 was not detected from any of the samples. Mycobacterium bovis was detected from one panela-style cheese sample. Nine additional samples yielded Mycobacterium spp.  相似文献   
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