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41.
This study documents the reliability and validity of a new infant-toddler authentic assessment, the Learning Through Relating Child Assets Record (LTR-CAR), and its feasibility of use by infant-toddler caregivers in an Early Head Start program. In a sample of 136 children, results indicated a strong internal structure of the LTR-CAR as evidenced by high internal consistency within age bands, expected performance in terms of the order of difficulty of items, and expected performance relative to the chronological ages of children. Moreover, the LTR-CAR accounted for a statistically significant amount of unique variance (between 6 and 26%), over and above age and gender, in six out of eight regressions predicting criterion measures. Given the increasing numbers of infants and toddlers in non-parental care, the need for authentic assessment as a tool to plan meaningful learning opportunities, as well as the lack of evidence-based authentic assessment options at the infant-toddler level, the LTR-CAR may provide a viable option for the field.  相似文献   
42.
In distributed and cooperative systems, the network structure is determinant to the success of the strategy adopted to solve complex tasks. Those systems are primarily governed by consensus protocols whose convergence is intrinsically dependent on the network topology. Most of the consensus algorithms deal with continuous values and perform average-based strategies to reach cohesion over the exchanged information. However, many problems demand distributed consensus over countable values, that cannot be handled by traditional protocols. In such a context, this work presents an approach based on semidefinite programming to design the optimal weights of a network adjacency matrix, in order to control the convergence of a distributed random consensus protocol for variables at the discrete-space domain, based on the voter model. As a second contribution, this work uses Markov theory and the biological inspiration of epidemics to find out a dynamical spreading model that can predict the information diffusion over this discrete consensus protocol. Also, convergence properties and equilibrium points of the proposed model are presented regarding the network topology. Finally, extensive numerical simulations evaluate the effectiveness of the proposed consensus algorithm, its spreading model, and the approach for optimal weight design.  相似文献   
43.
This study presents the basic lines of electronic administration in Spain. The complexity of the Spanish political-administrative system makes such a study challenging, in view of the considerable degree of autonomy and competences of the regional administrative bodies and local agencies with respect to the central government, the former being more visible in the 17 regions of Spain. Nonetheless, the central government maintains a series of legal instruments that allow a certain common framework of action to be imposed, aside from what is put into effect through diverse programs aimed precisely to develop common tools for the regions and municipalities of Spain. After an introduction that provides some necessary background, this study describes the legislative framework in which Spain's electronic administrative system has developed. The data included in the study refer to investment in information and communication technologies (ICT) and the services offered by the different Administrations on the internet; internet access by citizens, homes, businesses, and employees, as well as the interactivity existing with administrations by means of the internet; the origins and rise of various political initiatives of the Central Government involving electronic administration; and finally, the situation of civil service personnel, as catalysts of the success of Information Society in the Public Administration within Spain.  相似文献   
44.
Customer relationship management (CRM) and knowledge management (KM) have become key strategic tool for all companies, especially in the current competitive environment. Moreover, customer knowledge is an important issue for CRM implementation. Reviewing the literature, we found many studies that analyze the crucial role played by KM initiatives as determinants of the success of CRM. Moreover, we found also diverse studies that show high rates of failure when implementing that strategy, so there is still no integrated conceptual framework to guide companies to their successful implementation. In this paper, with data of 153 Spanish hotels, we examine the relationships between KM and CRM success using a structural equation model. The main contribution is that having knowledge management capabilities is not sufficient for the success of CRM, but there are other factors to consider. In particular, organizational factors indeed impact CRM success and they appear to be intermediaries of the impact of other factors (KM capabilities/technological/customer orientation factors) in the success of CRM (in financial and marketing terms).  相似文献   
45.
This paper investigates whether a green kind of design helps firms increase their capabilities for inventing in the environmental domain and whether it does so more than ‘standard’ design. It also investigates whether the effect of ‘green-matching’ between new design and technologies is conditional on firms’ innovative capabilities, as reflected by their R&D expenditure. We address these research questions with respect to the world's top R&D investors, looking at their intellectual property rights at the United States Patent and Trademark Office (USPTO) and proposing an original textual identification of green designs and trademarks. We find that green design increases environmental inventions by top R&D investors, and to a greater extent than non-environmental ones. Standard design also stimulates environmental inventions, but to a lesser extent than green design. The ‘green-matching’ actually helps, but internal innovative capabilities are required to make it effective: a green-tech ‘prize’ emerges from green design, but only once a minimum threshold of R&D expenditure has been reached.  相似文献   
46.
Education and Information Technologies - Mobile apps represent a resource with great potential for encouraging the development of many skills, given the high number of apps available and the quick...  相似文献   
47.
Videos can be used as didactic tools for self‐learning under several circumstances, including those cases in which students are responsible for the development of this resource as an audiovisual notebook. We compared students' and teachers' perceptions regarding the main features that an audiovisual notebook should include. Four questionnaires with items about information, images, text and music, and filmmaking were used to investigate students' (n = 115) and teachers' perceptions (n = 28) regarding the development of a video focused on a histological technique. The results show that both students and teachers significantly prioritize informative components, images and filmmaking more than text and music. The scores were significantly higher for teachers than for students for all four components analyzed. The highest scores were given to items related to practical and medically oriented elements, and the lowest values were given to theoretical and complementary elements. For most items, there were no differences between genders. A strong positive correlation was found between the scores given to each item by teachers and students. These results show that both students' and teachers' perceptions tend to coincide for most items, and suggest that audiovisual notebooks developed by students would emphasize the same items as those perceived by teachers to be the most relevant. Further, these findings suggest that the use of video as an audiovisual learning notebook would not only preserve the curricular objectives but would also offer the advantages of self‐learning processes. Anat Sci Educ 7: 209–218. © 2013 American Association of Anatomists.  相似文献   
48.
Electrosprays are a powerful technique to generate charged micro/nanodroplets. In the last century, the technique has been extensively studied, developed, and recognized with a shared Nobel price in Chemistry in 2002 for its wide spread application in mass spectrometry. However, nowadays techniques based on microfluidic devices are competing to be the next generation in atomization techniques. Therefore, an interesting development would be to integrate the electrospray technique into a microfluidic liquid-liquid device. Several works in the literature have attempted to build a microfluidic electrospray with disputable results. The main problem for its integration is the lack of knowledge of the working parameters of the liquid-liquid electrospray. The “submerged electrosprays” share similar properties as their counterparts in air. However, in the microfluidic generation of micro/nanodroplets, the liquid-liquid interfaces are normally stabilized with surface active agents, which might have critical effects on the electrospray behavior. In this work, we review the main properties of the submerged electrosprays in liquid baths with no surfactant, and we methodically study the behavior of the system for increasing surfactant concentrations. The different regimes found are then analyzed and compared with both classical and more recent experimental, theoretical and numerical studies. A very rich phenomenology is found when the surface tension is allowed to vary in the system. More concretely, the lower states of electrification achieved with the reduced surface tension regimes might be of interest in biological or biomedical applications in which excessive electrification can be hazardous for the encapsulated entities.  相似文献   
49.
Abstract High physical fitness in childhood and adolescence is positively associated with favourable health-related outcomes. Our aim was to examine the relationship between relatives' (father, mother, brother, sister, and best friend) physical activity engagement and encouragement on adolescents' physical fitness. Adolescents were part of the HELENA study, a multi-centre study conducted in 10 cities from nine European countries in 2006-2008. Participants were 3288 adolescents (48% boys, 52% girls) aged 12.5-17.5 years with valid data on at least one of the three fitness variables studied: muscular strength (standing long jump), speed/agility (4×10 m shuttle run), and cardiorespiratory fitness (20 m shuttle run). The adolescents reported their relatives' physical activity engagement and encouragement. Analysis of covariance showed that relatives' physical activity engagement (father, mother, brother, and best friend) was positively related to cardiorespiratory fitness (P?相似文献   
50.
As a mixture of new technologies, processes and services oriented to the citizen, e-government has become one of the most important keywords for the public sector reform with proponents claiming that it guarantees transparency, accountability and better communication between local and national administrations and their public. Few if any studies have investigated the factors that might contribute to the establishment of trusting relationship between city councils and citizens. This paper examines the relative importance and significance of three types of information communication technologies (ICTs) towards the use of e-government and the development of civic engagement. We conduct an empirical investigation of 179 Spanish official town websites (web sites in the municipalities). The research findings suggest that implementing ICT not only involves a step towards an increase in the use of e-government services by people, but also provides numerous opportunities for their civic engagement. The main conclusion of this study is that although ICT can leverage the adoption of e-government, it cannot create alone engagement with traditional activities of the local government. What is missing from this relationship is a mediating variable (adoption of e-government by government officers), which in turn can greatly help to better understand how ICT impacts relationships between governments and their citizens.  相似文献   
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