Most of the existing research on degrees-of-freedom (DoF) with imperfect channel state information at the transmitter (CSIT) assume the messages are private, which may not reflect reality as the two ...receivers can request the same content. To overcome this limitation, we therefore consider the hybrid unicast and multicast messages. In particular, we characterize the optimal DoF region for the two-user multiple-input multiple-output (MIMO) broadcast channel (BC) with imperfect CSIT and hybrid messages. For the converse, we establish a three-step procedure to exploit the utmost possible relaxation. For the achievability, since the DoF region is with specific three-dimensional structure regarding antenna configurations and CSIT qualities, we verify the existence or non-existence of corner point candidates via the feature of antenna configurations and CSIT qualities categorization, and provide a hybrid message-aware rate-splitting scheme. Besides, we show that to achieve the strictly positive corner points, it is unnecessary to split the unicast messages into private and common parts. This implies adding a multicast message may mitigate the rate-splitting complexity.
Marketers are increasingly relying on promotional practices (variously labeled as stealth marketing, hybrid messages, covert advertising) based on the diffusion of product information by third ...parties that appear to be independent of advertisers. In this paper, we examine to what extent the media treat their advertisers favorably, providing these advertisers' products extra visibility in supposedly neutral editorial content. Empirically, we model the determinant of media coverage of Italian fashion products in an extended dataset of consumer magazines in Italy, France, Germany, UK, and the USA. Research findings show that advertising is an important determinant of product placements in editorial content, and this result is consistent across countries and publishers. Our results imply that resource-rich advertisers engaging in compensatory advertising (that is, advertising investments that compensate poor product quality) might bias media coverage in their favor. Consumers will consequently be exposed twice to favorable messages about those products, in both advertisements and media content, resulting in higher purchases and reduced consumer welfare.
Posljednjih godina, medijski kritičari su izrazili veliku zabrinutost zbog nejasnih razgraničenja između dviju vrsta novinskih sadržaja: oglasa i uredničkog sadržaja. Cilj ovog rada jest da pokaže ...miješane novinarski i oglašivački diskurs na razini teksta. Koristim Fairclough's Critical Discourse Analysis pristup i kombiniram analizu tekstova i analizu diskursa u proučavanju i tumačenju teksta. Cilj rada je, između ostalog, ukazati na korist od Fairclough’s version of Critical Discourse Analysis kroz miješane poruke u miješanom diskursu s opažanjem sudionika i ciljanim intervjuima. Analiziram kako su miješane poruke u časopisu Obrazi bile konstruirane i tko je utjecao na njihovo osmišljavanje.
Rezultati pokazuju da postoje dva žanra miješanih poruka: kratke informativne poruke i miješani savjetodavni članci. Miješane poruke imaju prednost prednost pred nemiješanim člancima. Prije nego što časopise ide u tisak, oglašivači mogu provjeriti miješane poruke i promijeniti ih. Čineći to, ulaze u ulogu novinara I time novinari prestaju biti ti koji odlučuju na koji će način sadržaj biti predstavljen.
Analiza proizvodnje je razotkrila motive i svrhe sudionika u procesu proizvodnje miješanih poruka. Analiza diskursa pokazala je, kroz tekst, da novinari u promoviranju uključuju elemente diskursa koji su temeljeni na miješanim porukama.
Prikrivenih plaćenih novinarskih priloga (PPP-a) ili hibridnih poruka, u
javnosti poznatih pod nazivom prikriveno oglašavanje i PR-članci, danas je
sve više i u slovenskim tiskanim medijima. Autori u ...članku pokušavaju pokazati
da su prikriveno plaćeni novinarski prilozi – hibridne poruke – neka vrsta
mješavine oglasnih i novinarskih poruka. Tvrde da je to anomalija koja nije u
skladu s etičkim načelima ni jedne od uključenih struka: novinarske, oglašivačke
i struke odnosa s javnošću, dok je istodobno u suprotnosti sa slovenskim
Zakonom o medijima. Pitanja koja autori postavljaju jesu: kako bi bilo moguće
identificirati takve priloge i je li moguće spriječiti pojavu anomalnih priloga
u slovenskim medijima.
Given the requirements of increased data rate and massive connectivity in the Internet-of-things (IoT) applications of the fifth-generation communication systems (5G), non-orthogonal multiple access ...(NOMA) was shown to be capable of supporting more users than OMA. As a further potential enhancement, the faster-than-Nyquist (FTN) signaling is also capable of increasing the symbol rate. Since NOMA and FTN signaling impose non-orthogonalities from different perspectives, it is possible to achieve further increased spectral efficiency by exploiting both. Hence we investigate the FTN-NOMA uplink in the context of random access. Although random access schemes reduce the signaling overheads as well as latency, they require the base station to identify active users before performing data detection. As both inter-symbol and inter-user interferences exist, performing optimal detection requires a prohibitively high complexity. Moreover, in typical mobile communication environments, the channel envelope of users fluctuates violently, which imposes challenges on the receiver design. To tackle this problem, we propose a joint user activity tracking and data detection algorithm based on the factor graph framework, which relies on a sophisticated amalgam of expectation maximization (EM) and hybrid message passing algorithms. The complexity of the algorithm advocated only increases linearly with the number of active users. Our simulation results show that the proposed algorithm is effective in tracking user activity and detecting data symbols in dynamic random access systems.
The sparse code multiple access (SCMA) is a promising candidate for bandwidth-efficient next generation wireless communications, since it can support more users than the number of resource elements. ...On the same note, faster-than-Nyquist (FTN) signaling can also be used to improve the spectral efficiency. Hence in this paper, we consider a combined uplink FTN-SCMA system in which the data symbols corresponding to a user are further packed using FTN signaling. As a result, a higher spectral efficiency is achieved at the cost of introducing intentional inter-symbol interference (ISI). To perform joint channel estimation and detection, we design a low complexity iterative receiver based on the factor graph framework. In addition, to reduce the signaling overhead and transmission latency of our SCMA system, we intrinsically amalgamate it with grant-free scheme. Consequently, the active and inactive users should be distinguished. To address this problem, we extend the aforementioned receiver and develop a new algorithm for jointly estimating the channel state information, detecting the user activity and for performs data detection. In order to further reduce the complexity, an energy minimization based approximation is employed for restricting the user state to Gaussian. Finally, a hybrid message passing algorithm is conceived. Our Simulation results show that the FTN-SCMA system relying on the proposed receiver design has a higher throughput than conventional SCMA scheme at a negligible performance loss.
For the orthogonal time frequency space (OTFS) modulation, we generally multiplex symbols on a new type of carrier waveform in the delay-Doppler (DD) domain. These two parameters can be used to infer ...the range (R) and velocity (V) of the communication user and sensing target; thus, it is natural for the OTFS to be implemented in integrated sensing and communication (ISAC). A framework for ISAC based on OTFS modulation is proposed in this paper, in which the matched filter scheme with fractional parameter estimation is implemented for radar sensing. In addition, the hybrid message passing (MP) detection algorithm is developed for OTFS symbol demodulation. According to the simulation results, fractional DD shifts associated with multiple targets can be accurately obtained through the proposed framework. Meanwhile, the bit error rate under the proposed detector is less than 10-4 when the signal-to-noise ratio is high enough.
In this study, the authors address the problem of combining hierarchical and flat techniques to construct and maintain nodes’ connectivity as well as links’ symmetry (bidirectionality) in a wireless ...sensor network (WSN) comprising static nodes. They propose a localised and asynchronous self-stabilising hybrid message passing a solution that seamlessly merges three well known connectivity control techniques for such ad hoc networks, namely k-hop clustering $\lpar k \ge 1\rpar $(k≥1), power control (transmission range adjustment) and sleep/wake scheduling. Their stigmergy-based strategy (i.e. inspired from ants’ pheromone-based communication, division of labour and swarming behaviours) allows a WSN to simultaneously cope with issues such as scalability, fault tolerance, transmission range minimisation, energy hole problem (i.e. premature node deaths in the vicinity of the sink), channel overhearing and signalisation reduction. To the best of their knowledge, such a solution does not exist in the literature. The few self-stabilising hybrid connectivity control protocols currently proposed use only two of the above-mentioned techniques. The authors formally prove the correctness of their scheme and its self-stabilisation property under an unfair distributed daemon. Simulation results show that the proposed scheme has a low average convergence time, is energy efficient and can prolong network lifetime.
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