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71.
Maria-Iuliana Dascalu Constanta-Nicoleta Bodea Monica Nastasia Mihailescu Elena Alice Tanase Patricia Ordoñez de Pablos 《Behaviour & Information Technology》2016,35(4):290-297
The almost unlimited access to educational information plethora came with a drawback: finding meaningful material is not a straightforward task anymore. Recommender algorithms can be used to make smart decisions in complex information systems and help the users decide upon useful materials; therefore, they become a promising area in academia and industry. The current paper presents a survey on educational recommender systems (RS): a set of analysis criteria are exposed and the technological specifications and challenges of each analysed system are provided, in the context of the main trends in the development of RS. Also, an ontology-based educational recommendation mechanism is proposed and its application to lifelong learning is highlighted, proving that RS can successfully support new learning paradigms. 相似文献
72.
The combined study of the literature about human resource management and the resource‐based view of the firm and organizational learning provides an analysis framework useful for understanding how strategic human resource management systems contribute to the creation and development of a sustained competitive advantage for the firm. This article has two major aims. First, it provides a conceptual framework linking simultaneously three theoretical blocks: (a) human resource management, (b) organizational learning and knowledge management, and (c) sustained competitive advantage. Second, the article builds a causal model and tests it with a sample of Spanish firms from the manufacturing industry using structural equation modeling (SEM). After the performance of a cluster analysis, a group of 72 learning firms is identified and used to test the model. Finally, major conclusions and implications for management are drawn and further avenues for research are suggested. © 2008 Wiley Periodicals, Inc. 相似文献
73.
Information security is important in any organisation and particularly where personal and medical information is routinely recorded. Further, where the organisational culture revolves around trust, as in the medical environment, insider threats, both malicious and non-malicious, are difficult to manage. International research has shown that changing security culture and increasing awareness is necessary as technical resolutions are not sufficient to control insider threats. This area of information security is both important and topical in view of the recently publicised breaches of patient health information. Ensuring that all staff assumes responsibility for information security, particularly as part of an information security governance framework, is one practical solution to the problem of insider threats. 相似文献
74.
Digital microfluidic design and optimization of classic and new fluidic functions for lab on a chip systems 总被引:2,自引:2,他引:0
Yves Fouillet Dorothée Jary Claude Chabrol Patricia Claustre Christine Peponnet 《Microfluidics and nanofluidics》2008,4(3):159-165
This paper deals with microfluidic studies for lab-on-a-chip development. The first goal was to develop microsystems immediately
usable by biologists for complex protocol integrations. All fluid operations are performed on nano-liter droplet independently
handled solely by electrowetting on dielectric (EWOD) actuation. A bottom-up architecture was used for chip design due to
the development and validation of elementary fluidic designs, which are then assembled. This approach speeds up development
and industrialization while minimizing the effort in designing and simplifying chip-fluidic programming. Dispensing reproducibility
for 64 nl droplets obtained a CV below 3% and mixing time was only a few seconds. Ease of the integration was demonstrated
by performing on chip serial dilutions of 2.8-folds, four times. The second part of this paper concerns the development of
new innovative fluidic functions in order to extend EWOD-actuated digital fluidics’ capabilities. Experiments of particle
dispensing by EWOD droplet handling are reported. Finally, work is shown concerning the coupling of EWOD actuation and magnetic
fields for magnetic bead manipulation. 相似文献
75.
OBJECTIVES: The objectives were to measure the impact of specific features of imaging devices on tasks relevant to minimally invasive surgery (MIS) and to investigate cognitive and perceptual factors in such tasks. BACKGROUND: Although image-guided interventions used in MIS provide benefits for patients, they pose drawbacks for surgeons, including degraded depth perception and reduced field of view (FOV). It is important to identify design factors that affect performance. METHOD: In two navigation experiments, observers fed a borescope through an object until it reached a target. Task completion time and object shape judgments were measured. In a motion perception experiment, observers reported the direction of a line that moved behind an aperture. A motion illusion associated with reduced FOV was measured. RESULTS: Navigation through an object was faster when a preview of the object's exterior was provided. Judgments about the object's shape were more accurate with a preview (compared with none) and with active viewing (compared with passive viewing). The motion illusion decreased with a rectangular or rotating octagonal viewing aperture (compared with circular). CONCLUSIONS: Navigation performance may be enhanced when surgeons develop a mental model of the surgical environment, when surgeons (rather than assistants) control the camera, and when the shape of the image is designed to reduce visual illusions. APPLICATION: Unintentional contact between surgical tools and healthy tissues may be reduced during MIS when (a) visual aids permit surgeons to maintain a mental model of the surgical environment, (b) images are bound by noncircular apertures, and (c) surgeons manually control the camera. 相似文献
76.
Patricia Wouters 《国际水》2013,38(4):499-512
Abstract The exchange of data and information relating to transboundary water resources is widely accepted as being an appropriate starting point for more comprehensive cooperation. This paper examines under what conditions data and information exchange occur in relation to shared water resources, and hence examines when it can be used as a confidence building measure. An overview of several major international river basins together with more detailed case studies of the Mekong. Rio Grande, and Rhine River basins suggest that factors that promote data and information exchange include the presence of compatible needs, absence of legacies of mistrust, increasing water resources stress, perceptions that cooperation is of mutual benefit, external pressure and funding, comparable levels of institutional capacity, popular and political concern about water resources management, and functional formal or informal cooperative arrangements. Analysis of the situation prevailing between Israel and the Palestinians with regard to shared water resources suggests that data and information exchange does not seem likely in the short term, even though other forms of cooperation have been established with mixed results. This suggests that in some situations, at least, data and information exchange relating to shared water resources may not be useful as a first step in establishing more comprehensive cooperation. 相似文献
77.
Carbajal-Palacios P Balderas-Hernández P Ibanez JG Roa-Morales G 《Water science and technology》2012,66(5):1069-1073
The widely used standard method for chemical oxygen demand (COD) involves hazardous chromium species, and its two-hour heating protocol entails a substantial amount of energy expenditure. In the present work we report a proof of concept for a major modification of this method in the range 10-800 mgCOD/L, whereby H2O2 is proposed as a replacement oxidizer. This modification not only reduces the use of unsafe chromium species but also allows for the use of milder conditions that decrease the total energy outlay. The results are comparable with those obtained either with the standard method or with a commercial Hach? kit. 相似文献
78.
Rausova Z Chrenova J Nuutila P Iozzo P Dedik L 《Computer methods and programs in biomedicine》2012,107(2):347-356
New mathematical models from physiologically interpreted parameters capable of evaluating glucose metabolism within the liver and/or the whole body were developed. The group of pigs in a fasting state and the group of pigs with euglycemic supraphysiological hyperinsulinemia were scanned by positron emission tomography after a single dose of [(18)F]FDG tracer. Simultaneously frequent sampling of the dynamic data of [(18)F]FDG plasma concentration in artery, portal vein and hepatic vein was obtained. A system approach to the liver and/or the whole-body system by the tools of linear dynamic sysztem theory was used. Three kinds of structural models, single input and single output or multiple outputs and multiple inputs and single output, were identified. Differences between the group of fasting pigs and the group of pigs in euglycemic supraphysiological hyperinsulinemia were identified by estimated parameters of the structural models. The suitability of the structural mathematical models for the estimation of physiologically interpreted parameters from PET was validated. 相似文献
79.
We have identified and cloned the cDNAs encoding two odorant-binding proteins (OBPs) from the American palm weevil (APW) Rhynchophorus palmarum (Coleoptera, Curculionidae). Degenerate primers were designed from the N-terminal sequences and were used in polymerase chain reaction (PCR) in order to obtain full-length sequences in both males and females. In both sexes, two different cDNAs were obtained, encoding 123 and 115 amino acid-deduced sequences. Each sequence showed few amino acid differences between the sexes. The proteins were named RpalOBP2 and RpalOBP4 for male, RpalOBP2' and RpalOBP4' for female, with the types 2 and 4 presenting only 34% identities. These proteins shared high identity with previously described coleopteran OBPs. In native gels, RpalOBP2 clearly separated into two bands and RpalOBP4 into three bands, suggesting the presence of several conformational isomers. Thus, OBP diversity in this species may rely on both the presence of OBPs from different classes and the occurrence of isoforms for each OBP. 相似文献
80.
Characterization of Fractionated Soy Proteins Produced by a New Simplified Procedure 总被引:2,自引:0,他引:2
Nicolas A. Deak Patricia A. Murphy Lawrence A. Johnson 《Journal of the American Oil Chemists' Society》2007,84(2):137-149
It was possible to fractionate soy protein into two soy protein isolate fractions (>90% protein) enriched in either glycinin
or β-conglycinin by using a new simplified procedure (referred to as the Deak procedure) employing CaCl2 and NaHSO3. The Deak procedure produced fractions with higher yields of solids, protein, and isoflavones, and similar protein purities
as well as improved functional properties compared to fractions recovered by established, more complex soy protein fractionation
procedures. The Deak glycinin-rich fraction comprised 15.5% of the solids, 24.4% of the protein, and 20.5% of the isoflavones
in the starting soy flour, whereas the glycinin-rich fraction of the established procedure (Wu procedure) comprised only 11.6%
of the solids, 22.3% of the protein, and 9.6% of the isoflavones. The Deak β-conglycinin-rich fraction comprised 23.1% of
the solids, 37.1% of the protein, and 37.5% of the isoflavones in the starting soy flour, whereas the Wu β-conglycinin-rich
fraction comprised only 11.5% of the solids, 18.5% of the protein, and 3.3% of the isoflavones. Protein purities were >80%
for both fractions when using both procedures. The Wu procedure produced protein fractions with slightly higher solubilities
and similar surface hydrophobicities; whereas, the fractions produced by the Deak procedure had superior emulsification and
foaming properties and similar dynamic viscosity behaviors. 相似文献