994 resultados para Acoustic communication
Resumo:
How communication systems emerge and remain stable is an important question in both cognitive science and evolutionary biology. For communication to arise, not only must individuals cooperate by signaling reliable information, but they must also coordinate and perpetuate signals. Most studies on the emergence of communication in humans typically consider scenarios where individuals implicitly share the same interests. Likewise, most studies on human cooperation consider scenarios where shared conventions of signals and meanings cannot be developed de novo. Here, we combined both approaches with an economic experiment where participants could develop a common language, but under different conditions fostering or hindering cooperation. Participants endeavored to acquire a resource through a learning task in a computer-based environment. After this task, participants had the option to transmit a signal (a color) to a fellow group member, who would subsequently play the same learning task. We varied the way participants competed with each other (either global scale or local scale) and the cost of transmitting a signal (either costly or noncostly) and tracked the way in which signals were used as communication among players. Under global competition, players signaled more often and more consistently, scored higher individual payoffs, and established shared associations of signals and meanings. In addition, costly signals were also more likely to be used under global competition; whereas under local competition, fewer signals were sent and no effective communication system was developed. Our results demonstrate that communication involves both a coordination and a cooperative dilemma and show the importance of studying language evolution under different conditions influencing human cooperation.
Resumo:
The subject of communication between palliative care physicians and their patients regarding their diagnosis and prognosis has not been extensively researched. The purpose of this survey was to compare the attitudes and beliefs of palliative care specialists regarding communication with the terminally ill in Europe, South America, and Canada. A sample of palliative care physicians from South America (Argentina and Brazil), French-speaking Europe, and Canada were identified, and posted a questionnaire. Physicians who stated that they practised palliative care at least 30% of their time were considered evaluable as palliative care specialists. Of a total of 272 questionnaires, 228 were returned (84%); and 182/228 (81%) respondents were considered to be palliative care specialists. Palliative care physicians in all three regions believed that cancer patients should be informed of their diagnosis and the terminal nature of their illness. Physicians reported that at least 60% of their patients knew their diagnosis and the terminal stage of their illness in 52% and 24% of cases in South America, and 69% and 38% of cases in Europe, respectively. All physicians agreed that 'do not resuscitate' orders should be present, and should be discussed with the patient in all cases. While 93% of Canadian physicians stated that at least 60% of their patients wanted to know about the terminal stage of their illness, only 18% of South American, and 26% of European physicians said this (P < 0.001). Similar results were found when the physicians were asked the percentage of families who want patients to know the terminal stage of their illness. However, almost all of the physicians agreed that if they had terminal cancer they would like to know. There was a significant association between patient based decision-making and female sex (P = 0.007), older age (P = 0.04), and physicians from Canada and South America (P < 0.001). Finally, in their daily decision making, South American physicians were significantly more likely to support beneficence and justice as compared with autonomy. Canadian physicians were more likely to support autonomy as compared with beneficence. In summary, our findings suggest that there are major regional differences in the attitudes and beliefs of physicians regarding communication at the end of life. More research is badly needed on the attitudes and beliefs of patients, families, and health care professionals in different regions of the world.
Resumo:
Infants use their social competence very early to communicate not only in dyads but also in triads, in particular in the triangle they form with their mother and father. The development of this triangular communication is largely shaped by the ways the parents support or undermine each other in relation to their child. Whereas triangular communication is facilitated in "two for one" alliances, it is recruited in the service of regulating the parents' conflicts in "two against one" coalitions. These processes are manifest in toddlerhood and may be traced back to the coparenting alliance in formation during pregnancy.
Resumo:
Après une revue de la littérature concernant les médias utilisés dans le cadre de campagne de prévention, le matériel d'exposition est présenté. Le contenu et les moyens mis en oeuvre ne sont traités que dans la mesure où ils influencent directement la présentation du matériel. Enfin pour clore ce travail, une discussion concernant les possibilités et difficultés d'évaluation de ces actions de diffusion de l'information. [Auteur, p. 2]
Resumo:
Animals can compete for resources by displaying various acoustic signals that may differentially affect the outcome of competition. We propose the hypothesis that the most efficient signal to deter opponents should be the one that most honestly reveals motivation to compete. We tested this hypothesis in the barn owl (Tyto alba) in which nestlings produce more calls of longer duration than siblings to compete for priority access to the indivisible prey item their parents will deliver next. Because nestlings increase call rate to a larger extent than call duration when they become hungrier, call rate would signal more accurately hunger level. This leads us to propose three predictions. First, a high number of calls should be more efficient in deterring siblings to compete than long calls. Second, the rate at which an individual calls should be more sensitive to variation in the intensity of the sibling vocal competition than the duration of its calls. Third, call rate should influence competitors' vocalization for a longer period of time than call duration. To test these three predictions we performed playback experiments by broadcasting to singleton nestlings calls of varying durations and at different rates. According to the first prediction, singleton nestlings became less vocal to a larger extent when we broadcasted more calls compared to longer calls. In line with the second prediction, nestlings reduced vocalization rate to a larger extent than call duration when we broadcasted more or longer calls. Finally, call rate had a longer influence on opponent's vocal behavior than call duration. Young animals thus actively and differentially use multiple signaling components to compete with their siblings over parental resources.
Resumo:
In this paper, two probabilistic adaptive algorithmsfor jointly detecting active users in a DS-CDMA system arereported. The first one, which is based on the theory of hiddenMarkov models (HMM’s) and the Baum–Wech (BW) algorithm,is proposed within the CDMA scenario and compared withthe second one, which is a previously developed Viterbi-basedalgorithm. Both techniques are completely blind in the sense thatno knowledge of the signatures, channel state information, ortraining sequences is required for any user. Once convergencehas been achieved, an estimate of the signature of each userconvolved with its physical channel response (CR) and estimateddata sequences are provided. This CR estimate can be used toswitch to any decision-directed (DD) adaptation scheme. Performanceof the algorithms is verified via simulations as well as onexperimental data obtained in an underwater acoustics (UWA)environment. In both cases, performance is found to be highlysatisfactory, showing the near–far resistance of the analyzed algorithms.
Resumo:
In numerical linear algebra, students encounter earlythe iterative power method, which finds eigenvectors of a matrixfrom an arbitrary starting point through repeated normalizationand multiplications by the matrix itself. In practice, more sophisticatedmethods are used nowadays, threatening to make the powermethod a historical and pedagogic footnote. However, in the contextof communication over a time-division duplex (TDD) multipleinputmultiple-output (MIMO) channel, the power method takes aspecial position. It can be viewed as an intrinsic part of the uplinkand downlink communication switching, enabling estimationof the eigenmodes of the channel without extra overhead. Generalizingthe method to vector subspaces, communication in thesubspaces with the best receive and transmit signal-to-noise ratio(SNR) is made possible. In exploring this intrinsic subspace convergence(ISC), we show that several published and new schemes canbe cast into a common framework where all members benefit fromthe ISC.
Resumo:
Tämän tutkielman tavoitteena on selvittää informaatio- ja kommunikaatioyhteiskunnan vaikutusta paperin kulutukseen maailmanlaajuisesti. Tarkoituksena on löytää informaatio- ja kommunikaatioyhteiskuntaa kuvaavia mittareita, joiden avulla voidaan vertailla kehittyneitä ja kehittyviä markkina-alueita keskenään. Tutkimusongelmaan haetaan ratkaisua tutkimalla sekä kirjallisuutta että tilastoja, ja vertaamalla niitä esitettyihin teorioihin informaatio- ja kommunikaatioyhteiskunnan kehityksestä. Tutkielman avulla pyritään arvioimaan ja kuvaamaantoimintaympäristön muutoksia paperin kulutuksen suhteen pitkällä aikavälillä informaatio- ja kommunikaatioyhteiskunnan näkökulmasta.
Resumo:
Hearing loss can be caused by a variety of insults, including acoustic trauma and exposure to ototoxins, that principally effect the viability of sensory hair cells via the MAP kinase (MAPK) cell death signaling pathway that incorporates c-Jun N-terminal kinase (JNK). We evaluated the otoprotective efficacy of D-JNKI-1, a cell permeable peptide that blocks the MAPK-JNK signal pathway. The experimental studies included organ cultures of neonatal mouse cochlea exposed to an ototoxic drug and cochleae of adult guinea pigs that were exposed to either an ototoxic drug or acoustic trauma. Results obtained from the organ of Corti explants demonstrated that the MAPK-JNK signal pathway is associated with injury and that blocking of this signal pathway prevented apoptosis in areas of aminoglycoside damage. Treatment of the neomycin-exposed organ of Corti explants with D-JNKI-1 completely prevented hair cell death initiated by this ototoxin. Results from in vivo studies showed that direct application of D-JNKI-1 into the scala tympani of the guinea pig cochlea prevented nearly all hair cell death and permanent hearing loss induced by neomycin ototoxicity. Local delivery of D-JNKI-1 also prevented acoustic trauma-induced permanent hearing loss in a dose-dependent manner. These results indicate that the MAPK-JNK signal pathway is involved in both ototoxicity and acoustic trauma-induced hair cell loss and permanent hearing loss. Blocking this signal pathway with D-JNKI-1 is of potential therapeutic value for long-term protection of both the morphological integrity and physiological function of the organ of Corti during times of oxidative stress.
Resumo:
This paper aims to present an ePortfolio project led for two years in a multilingual and interdisciplinary Master's program in public discourse and communication analysis offered by the Faculty of Arts of the University of Lausanne (Switzerland). Globally, the project - named Learn to communicate skills - offers a reflection about academic skills and their transferability to the professional world. More precisely, the aim of the project is to make students aware of the importance of reflexive learning to make their skills transferable to other contexts.
Resumo:
Societies exchange knowledge, ideas and merchandise throughout their territories. Topography plays a fundamental role in the trajectory of such movements whilst helping to explain the distribution of human constructions. Standard GIS functions have been employed widely to simulate communication routes between settlements, but the straight application of published least cost route models proved inadequate for Mediterranean alluvial plain areas in which seasonal floods become an important factor to acknowledge. The objective of this study is the production of a new model, using topographic and hydrologic factors as variables from which it would be possible to simulate a route, and test it against known Roman itineraries. The selected Roman stretches are Girona – Coll de Pannisars and Tarragona – Montblanc. The new model shows the need to consider each case individually but also stresses the hydrologic factor, expressed in seasonal floods, as being of prime importance in the creation and development of Roman roads in Mediterranean alluvial plains.