103 resultados para SCIENTIFIC COMMUNICATION
Resumo:
La llista de distribució s'ha mostrat durant l'última dècada com una eina eficaç a l'hora de vertebrar la comunicació professional. De fet, és un primer pas cap a les comunitats virtuals. En aquest article s'estudia l'evolució d'un cas concret, IweTel, i de l'ús que els subscriptors van fer -ne, a partir de l'anàlisi de contingut dels missatges que van ser enviats entre 1998 i 2000. De l'estudi es desprèn que es tracta d'una llista utilitzada fonamentalment per a la comunicació professional i l'intercanvi d'informació, encara que pateix d'una falta notòria d'implicació activa per part dels seus subscriptors. Per altra banda, encara que han estat notables les millores fruit de la moderació, hi ha una absència viciosa de contingut científic o acadèmic en els debats desenvolupats.
Resumo:
Les comunitats virtuals d'usuaris (o CVU) han esdevingut una plataforma òptima per al treball cooperatiu i la investigació col·laborativa. El present treball descriu el desenvolupament de les CVUs acadèmiques i científiques espanyoles de RedIris a partir de la seva oferta d'eines i serveis d'informació. Els resultats mostren una gran dependència de les llistes de distribució i, en general, una infrautilització de les CVUs i dels seus serveis.
Resumo:
This paper attempts to study and analyze the tools and the information and communication services developed and offered by an evolving digital environment, as are virtual communities. It also seeks to observe the use that is made of all of this in function of to the objectives set out in different kinds of communities. In this way we want to verify whether virtual communities in Spain have reached maturity as tools for the creation and management of digital content. Specifically, we have looked at the diverse typology of these communities (leisure, business, and scientific-academic) and selected a sample of consolidated or paradigmatic cases in Spanish casuistry (Telepolis, CiudadFutura, RedIRIS, ICT) for each type.
Resumo:
Aquest document se centra en els casos dels dos principals partits espanyols (PP i PSOE) i catalans (PSC i CDC) en el període immediatament després de les eleccions generals espanyoles de maig de 2008, quan aquests celebraren els seus congressos. En general, es poden distingir tres tipus d'actors: en primer lloc, els ciberactivistes que tracten d'obtenir el reconeixement formal de la seva activitat en els seus partits. Així com, els líders del partit que poden intentar promoure la presència del partit en el ciberespai, però que també poden romandre indecisos perquè no és clar l'impacte electoral a la xarxa del ciberactivisme. Finalment, alguns militants tradicionals (off-line) solen ser reticents al reconeixement del ciberactivisme perquè amenaça les recompenses previstes dins del partit. Aquest article mostra com els nostres partits varen respondre al desafiament del ciberactivisme i arriba a la conclusió que la seva situació electoral, mediada per la seva ideologia, estructura organitzativa i el tipus de militància, poden ajudar-nos a comprendre el grau diferent d'institucionalització en l'organització del partit.
Resumo:
We study experimentally how the ability to communicate affects the frequency and effectiveness of flexible and inflexible contracts in a bilateral trade context where sellers can adjust trade quality after observing a post-contractual cost shock and a discretionary buyer transfer. In the absence of communication, we find that rigid contracts are more frequent and lead to higher earnings for both buyer and seller. By contrast, in the presence of communication, flexible contracts are much more frequent and considerably more productive, both for buyers and sellers. Also, both buyer and seller earn considerably more from flexible with communication than rigid without communication. Our results show quite strongly that communication, a normal feature in contracting, can remove the potential cost of flexibility (disagreements caused by conflicting perceptions). We offer an explanation based on social norms.
Resumo:
This is an exploratory study that aims, on the one hand, to examine in more detail how children between 12 and 16 years of age use different audiovisual technologies, what they feel and think when using them, and whom they like to speak to about such experiences. On the other hand, we look more deeply into the interactions between adults and children, particularly between parents and their children, in relation to these technologies when children use them at home or in other places. We analysed responses to questionnaires with several common items, administered separately to parents and children. Children’s responses reflect an important level of dissatisfaction when talking with different adults about media activities. Our findings support the thesis that more and more children socialise through new information and communication technologies with little or no recourse to adult criteria, giving rise to the emergence of specific children’s cultures. Crossing of the responses of parents and those of their own children shows us which aspects of media reality adults overestimate or underestimate in comparison to children, and to what degree certain judgements coincide and differ between generations. The results can be applied to the improvement of relations between adults and adolescents, taking advantage of adolescents’ strong motivation to engage in activities using audiovisual media
Resumo:
Report for the scientific sojourn carried out at the School of Computing of the University of Dundee, United Kingdom, from 2010 to 2012. This document is a scientific report of the work done, main results, publications and accomplishment of the objectives of the 2-year post-doctoral research project with reference number BP-A 00239. The project has addressed the topic of older people (60+) and Information and Communication Technologies (ICT), which is a topic of growing social and research interest, from a Human-Computer Interaction perspective. Over a 2-year period (June 2010-June 2012), we have conducted classical ethnography of ICT use in a computer clubhouse in Scotland, addressing interaction barriers and strategies, social sharing practices in Social Network Sites, and ICT learning, and carried out rapid ethnographical studies related to geo-enabled ICT and e-government services towards supporting independent living and active ageing. The main results have provided a much deeper understanding of (i) the everyday use of Computer-Mediated Communication tools, such as video-chats and blogs, and its evolution as older people’s experience with ICT increases over time, (ii) cross-cultural aspects of ICT use in the north and south of Europe, (iii) the relevance of cognition over vision in interacting with geographical information and a wide range of ICT tools, despite common stereotypes (e.g. make things bigger), (iv) the important relationship offline-online to provide older people with socially inclusive and meaningful eservices for independent living and active ageing, (v) how older people carry out social sharing practices in the popular YouTube, (vi) their user experiences and (vii) the challenges they face in ICT learning and the strategies they use to become successful ICT learners over time. The research conducted in this project has been published in 17 papers, 4 in journals – two of which in JCR, 5 in conferences, 4 in workshops and 4 in magazines. Other public output consists of 10 invited talks and seminars.
Resumo:
In this paper we present the theoretical and methodologicalfoundations for the development of a multi-agentSelective Dissemination of Information (SDI) servicemodel that applies Semantic Web technologies for specializeddigital libraries. These technologies make possibleachieving more efficient information management,improving agent–user communication processes, andfacilitating accurate access to relevant resources. Othertools used are fuzzy linguistic modelling techniques(which make possible easing the interaction betweenusers and system) and natural language processing(NLP) techniques for semiautomatic thesaurus generation.Also, RSS feeds are used as “current awareness bulletins”to generate personalized bibliographic alerts.
Resumo:
Expressions relating spectral efficiency, power, and Doppler spectrum, are derived for Rayleigh-faded wireless channels with Gaussian signal transmission. No side information on the state of the channel is assumed at the receiver. Rather, periodic reference signals are postulated in accordance with the functioning of most wireless systems. The analysis relies on a well-established lower bound, generally tight and asymptotically exact at low SNR. In contrast with most previous studies, which relied on block-fading channel models, a continuous-fading model is adopted. This embeds the Doppler spectrum directly in the derived expressions, imbuing them with practical significance. Closed-form relationships are obtained for the popular Clarke-Jakes spectrum and informative expansions, valid for arbitrary spectra, are found for the low- and high-power regimes. While the paper focuses on scalar channels, the extension to multiantenna settings is also discussed.
Resumo:
The analysis of the multiantenna capacity in the high-SNR regime has hitherto focused on the high-SNR slope (or maximum multiplexing gain), which quantifies the multiplicative increase as function of the number of antennas. This traditional characterization is unable to assess the impact of prominent channel features since, for a majority of channels, the slope equals the minimum of the number of transmit and receive antennas. Furthermore, a characterization based solely on the slope captures only the scaling but it has no notion of the power required for a certain capacity. This paper advocates a more refined characterization whereby, as function of SNRjdB, the high-SNR capacity is expanded as an affine function where the impact of channel features such as antenna correlation, unfaded components, etc, resides in the zero-order term or power offset. The power offset, for which we find insightful closed-form expressions, is shown to play a chief role for SNR levels of practical interest.
Resumo:
Expressions relating spectral efficiency, power and Doppler spectrum are derived for low-power Rayleighfaded wireless channels with proper complex signaling. Noside information on the state of the channel is assumed at the receiver. Rather, periodic reference signals are postulated inaccordance with the functioning of most wireless systems. In contrast with most previous studies, which relied on block-fading channel models, a continuous-fading model is adopted. This embeds the Doppler spectrum directly in thederived expressions thereby imbuing them with practical significance.
Resumo:
The optimization of the pilot overhead in wireless fading channels is investigated, and the dependence of this overhead on various system parameters of interest (e.g., fading rate, signal-to-noise ratio) is quantified. The achievable pilot-based spectral efficiency is expanded with respect to the fading rate about the no-fading point, which leads to an accurate order expansion for the pilot overhead. This expansion identifies that the pilot overhead, as well as the spectral efficiency penalty with respect to a reference system with genie-aided CSI (channel state information) at the receiver, depend on the square root of the normalized Doppler frequency. It is also shown that the widely-usedblock fading model is a special case of more accurate continuous fading models in terms of the achievable pilot-based spectral efficiency. Furthermore, it is established that the overhead optimization for multiantenna systems is effectively the same as for single-antenna systems with thenormalized Doppler frequency multiplied by the number of transmit antennas.
Resumo:
We analyze the role of commitment in pre-play communication for ensuring efficient evolutionarily stable outcomes in coordination games. All players are a priori identical as they are drawn from the same population. In games where efficient outcomes can be reached by players coordinating on the same action we find commitment to be necessary to enforce efficiency. In games where efficienct outcomes only result from play of different actions, communication without commitment is most effective although efficiency can no longer be guaranteed. Only when there are many messages then inefficient outcomes are negligible as their basins of attraction become very small.
Resumo:
The effectiveness of pre-play communication in achieving efficientoutcomes has long been a subject of controversy. In some environments,cheap talk may help to achieve coordination. However, Aumannconjectures that, in a variant of the Stag Hunt game, a signal forefficient play is not self-enforcing and concludes that an "agreementto play [the efficient outcome] conveys no information about what theplayers will do." Harsanyi and Selten (1988) cite this example as anillustration of risk-dominance vs. payoff-dominance. Farrell and Rabin(1996) agree with the logic, but suspect that cheap talk willnonetheless achieve efficiency. The conjecture is tested with one-waycommunication. When the sender first chooses a signal and then anaction, there is impressive coordination: a 94% probability for thepotentially efficient (but risky) play, given a signal for efficientplay. Without communication, efforts to achieve efficiency wereunsuccessful, as the proportion of B moves is only 35%. I also test ahypothesis that the order of the action and the signal affects theresults, finding that the decision order is indeed important. WhileAumann s conjecture is behaviorally disconfirmed when the signal isdetermined initially, the signal s credibility seems to be much moresuspect when the sender is known to have first chosen an action, andthe results are not statistically distinguishable from those whenthere is no signal. Some applications and issues in communication andcoordination are discussed.