717 resultados para user engagement
Resumo:
The explosive growth of Internet during the last years has been reflected in the ever-increasing amount of the diversity and heterogeneity of user preferences, types and features of devices and access networks. Usually the heterogeneity in the context of the users which request Web contents is not taken into account by the servers that deliver them implying that these contents will not always suit their needs. In the particular case of e-learning platforms this issue is especially critical due to the fact that it puts at stake the knowledge acquired by their users. In the following paper we present a system that aims to provide the dotLRN e-learning platform with the capability to adapt to its users context. By integrating dotLRN with a multi-agent hypermedia system, online courses being undertaken by students as well as their learning environment are adapted in real time
Resumo:
Proactive career behaviors become increasingly important in today's career environment, but little is known about how and when motivational patterns affect individual differences. In a six-month longitudinal study among German university students (Study 1; N = 289) it was demonstrated that motivation in terms of "can do" (self-efficacy and context beliefs), "reason to" (autonomous career goals), and "energized to" (positive affect) significantly predicted career behaviors. Contrary to expectation, negative context beliefs had a positive effect when combined with other motivational states. Study 2 replicated and extended those results by investigating whether "can do" motivation mediates the effect of proactive personality and whether those effects are conditional upon the degree of career choice decidedness. We tested a moderated multiple mediation model with a unique sample of 134 German students, assessed three times, each interval being 6 weeks apart. The results showed that effects of proactivity were partially carried through higher self-efficacy beliefs but not context beliefs. Supporting a moderation model, indirect effects through self-efficacy beliefs were not present for students with very low decidedness.
Resumo:
We characterize the capacity-achieving input covariance for multi-antenna channels known instantaneously at the receiver and in distribution at the transmitter. Our characterization, valid for arbitrary numbers of antennas, encompasses both the eigenvectors and the eigenvalues. The eigenvectors are found for zero-mean channels with arbitrary fading profiles and a wide range of correlation and keyhole structures. For the eigenvalues, in turn, we present necessary and sufficient conditions as well as an iterative algorithm that exhibits remarkable properties: universal applicability, robustness and rapid convergence. In addition, we identify channel structures for which an isotropic input achieves capacity.
Resumo:
The problem of jointly estimating the number, the identities, and the data of active users in a time-varying multiuser environment was examined in a companion paper (IEEE Trans. Information Theory, vol. 53, no. 9, September 2007), at whose core was the use of the theory of finite random sets on countable spaces. Here we extend that theory to encompass the more general problem of estimating unknown continuous parameters of the active-user signals. This problem is solved here by applying the theory of random finite sets constructed on hybrid spaces. We doso deriving Bayesian recursions that describe the evolution withtime of a posteriori densities of the unknown parameters and data.Unlike in the above cited paper, wherein one could evaluate theexact multiuser set posterior density, here the continuous-parameter Bayesian recursions do not admit closed-form expressions. To circumvent this difficulty, we develop numerical approximationsfor the receivers that are based on Sequential Monte Carlo (SMC)methods (“particle filtering”). Simulation results, referring to acode-divisin multiple-access (CDMA) system, are presented toillustrate the theory.
Resumo:
This project explores the user costs and benefits of winter road closures. Severe winter weather makes travel unsafe and dramatically increases crash rates. When conditions become unsafe due to winter weather, road closures should allow users to avoid crash costs and eliminate costs associated with rescuing stranded motorists. Therefore, the benefits of road closures are the avoided safety costs. The costs of road closures are the delays that are imposed on motorists and motor carriers who would have made the trip had the road not been closed. This project investigated the costs and benefits of road closures and found that evaluating the benefits and costs is not as simple as it appears. To better understand the costs and benefits of road closures, the project investigates the literature, conducts interviews with shippers and motor carriers, and conducts case studies of road closures to determine what actually occurred on roadways during closures. The project also estimates a statistical model that relates weather severity to crash rates. Although, the statistical model is intended to illustrate the possibility to quantitatively relate measurable and predictable weather conditions to the safety performance of a roadway. In the future, weather conditions such as snow fall intensity, visibility, etc., can be used to make objective measures of the safety performance of a roadway rather than relying on subjective evaluations of field staff. The review of the literature and the interviews clearly illustrate that not all delays (increased travel time) are valued the same. Expected delays (routine delays) are valued at the generalized costs (value of the driver’s time, fuel, insurance, wear and tear on the vehicle, etc.), but unexpected delays are valued much higher because they result in interruption of synchronous activities at the trip’s destination. To reduce the costs of delays resulting from road closures, public agencies should communicate as early as possible the likelihood of a road closure.
Resumo:
This paper presents the platform developed in the PANACEA project, a distributed factory that automates the stages involved in the acquisition, production, updating and maintenance of Language Resources required by Machine Translation and other Language Technologies. We adopt a set of tools that have been successfully used in the Bioinformatics field, they are adapted to the needs of our field and used to deploy web services, which can be combined to build more complex processing chains (workflows). This paper describes the platform and its different components (web services, registry, workflows, social network and interoperability). We demonstrate the scalability of the platform by carrying out a set of massive data experiments. Finally, a validation of the platform across a set of required criteria proves its usability for different types of users (non-technical users and providers).
Resumo:
This paper presents a webservice architecture for Statistical Machine Translation aimed at non-technical users. A workfloweditor allows a user to combine different webservices using a graphical user interface. In the current state of this project,the webservices have been implemented for a range of sentential and sub-sententialaligners. The advantage of a common interface and a common data format allows the user to build workflows exchanging different aligners.
Resumo:
The aim of this paper is to examine the various controversies over the genuineproblems of toleration in a plurally diverse polity as both historically andconceptually, toleration is one of the foundational characteristics that defines thevery essence of a plurally diverse polity and the basic virtue associated with a liberalconception of citizenship. In section 1, I present the main philosophical andconceptual issues related to the toleration-based approach to diversity in liberalpolitical theory. In section 2 I identify the conditions and the circumstances oftoleration. I articulate in Section 3 the most pressing objections against toleration. Ipresent in section 4 two competing approaches to the toleration-based approach todiversity is faced with. In the concluding section, I outline a modified conception oftoleration that mediates between different requirements associated with the twoprincipled commitments of the liberal version of the rights-based conception ofcitizenship.
Resumo:
The aim of this study was to examine the influence of child's gender on several dimensions-of paternity: the fathers' personal experience of paternity, their involvement in child rearing, and their representations. A total of 147 Swiss fathers of 18-month-old children (65 girls and 82 boys) relationship to the child or relationship with the child's completed questionnaires. The child's gender had little influence on paternal experience, mother. Globally, the fathers took on few responsibilities which were largely devolved to mothers. Fathers of boys were more involved in child care than fathers of girls. Finally, a discrepancy was found between the fathers representations of paternal roles in rearing girls and boys and the actual level of responsibility that fathers adopted in their relationship with their child.