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921.
In this paper, a model describing the castor three-dimensional dynamic behavior, is presented. A procedure, based on the Udwadia-Kalaba formulation has been implemented to write the castor non-linear motion equations. The model takes into account the flexural and lateral compliance of the castor frame and the phenomena related to the wheel rotation. To prescind from the wheel-road interaction parameters, the hypothesis of no sideslip of the wheel has been adopted but other tire models can be easily implemented. The non-linear system stability is evaluated integrating the motion equations and performing a fitting procedure on the natural steering oscillation.  相似文献   
922.
The internationalisation process has been described as a process of learning under which a business increases its commitment abroad as the company acquires knowledge on new markets and on the nature of the process itself. The present work proposes a model that relates the possession of a base of knowledge originated in supra-organisational, organisational and individual sources, as the actively new decision of seeking knowledge related to the start of the exporting activity. Integrating the literature on the pre-export behaviour of the business and the theory of organisational learning, we propose that such relationship is influenced by two dimensions: the export intention and the context of unlearning. The sample included 103 SMEs in the pre-exporting phase. Results support the conception of the process of internationalisation as a process of learning under which a prior base of knowledge is combined with periods of unlearning and a search for new knowledge.  相似文献   
923.
Social content systems contain enormous collections of unstructured user-generated content, annotated by the collaborative effort of regular Internet users. Tag-clouds have become popular interfaces that allow users to query the database of these systems by clicking relevant terms. However, these single click queries are often not expressive enough to effectively retrieve the desired content. Users have to use multiple clicks or type longer queries to satisfy their information need.  相似文献   
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IntroductionThe Fourth Universal Definition of Myocardial Infarction Global Taskforce recommends the use of high sensitive troponin (hs-Tn) assays in the diagnosis of acute myocardial infarction. We evaluated the analytical performance of the Atellica IM High-sensitivity Troponin I Assay (hs-TnI) (Siemens Healthcare Diagnostics Inc., Tarrytown, USA) and compared its performance to other hs-TnI assays (Siemens Advia Centaur, Dimension Vista, Dimension EXL, and Abbott Architect (Wiesbaden, Germany)) at one or more sites across Europe.Materials and methodsPrecision, detection limit, linearity, method comparison, and interference studies were performed according to Clinical and Laboratory Standards Institute protocols. Values in 40 healthy individuals were compared to the manufacturer’s cut-offs. Sample turnaround time (TAT) was examined.ResultsImprecision repeatability CVs were 1.1–4.7% and within-lab imprecision were 1.8–7.6% (10.0–25,000 ng/L). The limit of blank (LoB), detection (LoD), and quantitation (LoQ) aligned with the manufacturer’s values of 0.5 ng/L, 1.6 ng/L, and 2.5 ng/L, respectively. Passing-Bablok regression demonstrated good correlations between Atellica IM analyser with other systems; some minor deviations were observed. All results in healthy volunteers fell below the 99th percentile URL, and greater than 50% of each sex demonstrated values above the LoD. No interference was observed for biotin (≤ 1500 µg/L), but a slight bias at 5.0 g/L haemoglobin and 50 ng/L Tn was observed. TAT from was fast (mean time = 10.9 minutes) and reproducible (6%CV).ConclusionsReal-world analytical and TAT performance of the hs-TnI assay on the Atellica IM analyser make this assay fit for routine use in clinical laboratories.  相似文献   
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In recent years, university education has changed considerably, adapting to the prevailing circumstances and proving itself an essential resource in the optimisation of the professional, social and cultural domains. In short, the changes experienced by university education have led to the achievement of quite significant results. However, at the same time we have also witnessed the emergence of certain misgivings about the nature of this education, above all in relation to the personal, ethical and civic development of today’s student populace. This paper focuses on these concerns, and in so doing, it revisits a past in which essential philosophical ideas were being formulated about higher education, ideas that this paper argues are highly pertinent to current reality.  相似文献   
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This paper considers the potential impact that the nascent technology of quantum computing may have on society. It focuses on three areas: cryptography, optimization, and simulation of quantum systems. We will also discuss some ethical aspects of these developments, and ways to mitigate the risks.  相似文献   
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