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161.
162.
This paper addresses the flocking motion problem for swarms of agents with two restrictions: limited communication/detection ranges and different input constraints. In this problem, the distance between pairs of agents determines if a communication/detection link exists among them, while each agent has a different control action bound. We use the notion of proximity graph to model communication/detection between agents and provide distributed controllers designed for leaderless and leader-followers flocking motion scenarios. Our proposed designs preserve the connectivity of the proximity graph while the control effort satisfies the bound of each particular agent. Unlike previous results, our protocols take advantage of the group’s input heterogeneity to use agents with a greater capacity to compensate for neighbors that are less capable of meeting the group’s requirements. Additionally, our designs are based only on local state errors and are robust to non-modeled edge failures. To illustrate the effectiveness of our proposal, we use numerical simulations of different flocking scenarios.  相似文献   
163.
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   
164.
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   
165.
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   
166.
Educational technology research and development - The objective has been to know the impact of the flipped classroom methodology on the academic performance of students during their training...  相似文献   
167.
Education and Information Technologies - Computational thinking in the educational environment has awaken a rising interest, having been included as part of the curricula from the very beginnings...  相似文献   
168.
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   
169.
The tools used in learning processes are in a continuous state of flux. One of the most significant changes is the application of Information and Communications technologies (ICTs) to educational contexts. This provides new possible ways to carry out learning activities, new learning services, the possibility to use new kinds of contents and activities, etc. However, ICTs have not provided as many advantages as they were supposed to, so changes are necessary. In this context, a new set of tools, Web 2.0, offers a new way to understand the Web, in which the user is the centre. Further, users can cooperate in order to define contents. This concept is also applied in technology-mediated learning but there are important problems when one tries to integrate such tools and concepts with existing systems. This paper explores the integration of these tools in traditional learning environments, the various possibilities and their advantages and drawbacks. After that, an interoperability scenario is described and two experiences are presented to show how 2.0 tools can be integrated in learning activities, and its effect in educational process.  相似文献   
170.
This paper focuses on institutionally powered personal learning environments (iPLEs). The concept of the iPLE can be seen as a way universities can incorporate learner-centred approach into the architecture of their technology-enhanced learning environments. The aim of this paper is to pose that there are other ways to learn complementary to virtual learning environments, such as using distributed Web 2.0 tools from personal learning environments (PLEs). With that aim in mind, this paper presents an exploratory study with two different iPLE configurations, analyses how they modify the learning–teaching process, and reports their perceived usefulness from the students' point of view. These two case studies were carried out by a research group of educational technology from a Spanish university in graduate and postgraduate courses. As reported by other case studies, the results revealed that students use the environment basically in the academic context and this usage is conceived as another time and effort requiring task. This fact can be observed in the low level iPLEs customization. The overall conclusions we can extract are, on the one hand, that the new environment to integrate informal and formal learning should be flexible and adaptable to the student's needs and preferences and, on the other hand, that academic tools might someday become personal tools.  相似文献   
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