While the messaging tactics of extremist organizations have been studied by researchers, little attention has been devoted to understanding how alternative multimodal communications can enable ...resistance to polarizing content. This article takes as case studies three grassroots youth arts projects that deploy multimodal resources to educate and build resilience: Build Solid Ground, Jamal al-Khatib and Loulu. The projects won awards at the Horizon 2020 Building Resilience to Violent Extremism and Polarisation (BRaVE) Fair, which was hosted by the Berlin-based intercultural organization Cultures Interactive and took place via Zoom in November 2020. In the pandemic context of increased time spent online, polarization, and growing social and structural vulnerability in which young people face uncertain futures, these projects have been selected for their ability to build channels of communication that support pro-social resilience.
The deployment of aerial base stations (ABSs) on unmanned aerial vehicles (UAVs) presents a promising solution for extending cellular connectivity to areas where terrestrial infrastructure is ...overloaded, damaged, or absent. A pivotal challenge in this domain is to decide the locations of a set of ABSs to effectively serve ground-based users. Most existing approaches oversimplify this problem by assuming that the channel gain between two points is a function of solely distance and, sometimes, also the elevation angle. In turn, this paper leverages propagation radio maps to account for arbitrary air-to-ground channel gains. This methodology enables the identification of an approximately minimal set of locations where ABSs need to be deployed to ensure that all ground terminals achieve a target service rate, while adhering to backhaul capacity limitations and avoiding designated no-fly zones. Relying on a convex relaxation technique and the alternating direction method of multipliers (ADMM), this paper puts forth a scalable solver whose computational complexity scales linearly with the number of ground terminals. Convergence is established analytically and an extensive set of simulations corroborate the merits of the proposed scheme relative to conventional methods.
This paper studies power allocation for performance constrained dual-hop variable-gain amplify-and-forward (AF) relay networks in Nakagami-Formula Omitted fading. In this context, the performance ...constraint is formulated as a constraint on the end-to-end signal-to-noise-ratio (SNR) and the overall power consumed is minimized while maintaining this constraint. This problem is considered under two different assumptions of the available channel state information (CSI) at the relays, namely full CSI at the relays and partial CSI at the relays. In addition to the power minimization problem, we also consider the end-to-end SNR maximization problem under a total power constraint for the partial CSI case. We provide closed-form solutions for all the problems which are easy to implement except in two cases, namely selective relaying with partial CSI for power minimization and SNR maximization, where we give the solution in the form of a one-variable equation which can be solved efficiently. Numerical results are then provided to characterize the performance of the proposed power allocation algorithms considering the effects of channel parameters and CSI availability.
In quantum Shannon theory, the way information is encoded and decoded takes advantage of the laws of quantum mechanics, while the way communication channels are interlinked is assumed to be ...classical. In this Letter, we relax the assumption that quantum channels are combined classically, showing that a quantum communication network where quantum channels are combined in a superposition of different orders can achieve tasks that are impossible in conventional quantum Shannon theory. In particular, we show that two identical copies of a completely depolarizing channel become able to transmit information when they are combined in a quantum superposition of two alternative orders. This finding runs counter to the intuition that if two communication channels are identical, using them in different orders should not make any difference. The failure of such intuition stems from the fact that a single noisy channel can be a random mixture of elementary, noncommuting processes, whose order (or lack thereof) can affect the ability to transmit information.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UL, UM
Green technology is the means of improving towards the rising environmental concern. The implication of green fertilizer technology (GFT) is the need for the modern development of environmentally ...friendly technology, also to increase the production level among all the agriculture crops. It is especially needed for paddy production, as it has always been considered as an important commodity because it is the main staple food for the nation. Paddy production in Malaysia using GFT allows for sustainable development and boosts the yield. Nevertheless, the adoption rate of GFT is unsatisfactory in most of the developing countries, including in Malaysia. The fact that the cost of production is considerably higher results in low-level perception regarding the adoption of GFT. Hence, the integration of communication and technology factors could become one of the main elements for the further development of the paddy sector in Malaysia. The overall objective of this research study will identify the factors that determine paddy farmer's adoption decision on GFT in Malaysia. To do so, a literature review was compiled on the topic of agriculture innovation-based adoption decision theories such as Diffusion of innovation (DOI), Theory of reasoned action (TRA), Theory of Planned Behavior (TPB) and Technology acceptance model (TAM) and communication channels to study paddy farmers' adoption decision of GFT. The results of the review revealed that this framework highlights adoption as an intricate behavior, interweaving aspects such as communication channels, socio-psychological and innovation attribute considerations. The conceptual framework illuminates the decision towards adoption as a self-motivated process, assumes a composite interaction among groups of variables coming from two different theories. The combination of DOI, TRA, TPB, TAM and communication channels overcome some limitations that arise when the only theory is used to examine the adoption decision among paddy farmers in Malaysia. Correspondingly, there has been limited empirical research done on the decision of adoption toward GFT use among paddy farmers in Malaysia.
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•Inclusive outline of the existing hurdles for paddy farmer’s awareness of GFT.•The framework of the theoretic standpoints which have to develop paddy farmer’s intention to considers GFT.•Researcher recognizes the loopholes in the recent research and proposes prospective ideas in area GFT adoption where solid contribution needed.•This review study examines the innovation attributes, socio-psychological and communication channels to the adoption of GFT.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•The purpose of the study is to identify how the choice of communication media affects internal communication satisfaction.•We conducted an analysis of the most commonly used channels in corporations ...and linked the results to employees’ satisfaction and media choice.•In exploring internal communication satisfaction and satisfaction with media we found a strong positive correlation between the variables.•The companies that put a bigger effort into adjusting their media towards their employees’ needs, have more satisfied internal audience.
As the environment of internal communication is continually changing for a multitude of reasons, especially new technologies, organizations have to adapt fast in their attempts to reach their employees. When deciding on the type of channel to use, internal communication managers should be aware of their employees’ preferences. The purpose of this study is to identify how the choice of internal communication media affects internal communication satisfaction. In order to explore this relationship further, we conducted an analysis of the most commonly used internal communication channels in ten large corporations and linked the results to employees’ satisfaction and media choice. By expanding the knowledge on preferred communication channels, we are hoping to provide some insight for better management of internal communication.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Sharing of the frequency bands between radar and communication systems has attracted substantial attention, as it can avoid under-utilization of otherwise permanently allocated spectral resources, ...thus improving efficiency. Further, there is increasing demand for radar and communication systems that share the hardware platform as well as the frequency band, as this not only decongests the spectrum, but also benefits both sensing and signaling operations via the full cooperation between both functionalities. Nevertheless, the success of spectrum and hardware sharing between radar and communication systems critically depends on high-quality joint radar and communication designs. In the first part of this paper, we overview the research progress in the areas of radar-communication coexistence and dual-functional radar-communication (DFRC) systems, with particular emphasis on application scenarios and technical approaches. In the second part, we propose a novel transceiver architecture and frame structure for a DFRC base station (BS) operating in the millimeter wave (mmWave) band, using the hybrid analog-digital (HAD) beamforming technique. We assume that the BS is serving a multi-antenna user equipment (UE) over a mmWave channel, and at the same time it actively detects targets. The targets also play the role of scatterers for the communication signal. In that framework, we propose a novel scheme for joint target search and communication channel estimation, which relies on omni-directional pilot signals generated by the HAD structure. Given a fully-digital communication precoder and a desired radar transmit beampattern, we propose to design the analog and digital precoders under non-convex constant-modulus (CM) and power constraints, such that the BS can formulate narrow beams towards all the targets, while pre-equalizing the impact of the communication channel. Furthermore, we design a HAD receiver that can simultaneously process signals from the UE and echo waves from the targets. By tracking the angular variation of the targets, we show that it is possible to recover the target echoes and mitigate the resulting interference to the UE signals, even when the radar and communication signals share the same signal-to-noise ratio (SNR). The feasibility and efficiency of the proposed approaches in realizing DFRC are verified via numerical simulations. Finally, the paper concludes with an overview of the open problems in the research field of communication and radar spectrum sharing (CRSS).
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Owing to the inevitable loss in communication channels, the distance of entanglement distribution is limited to approximately 100 kilometres on the ground
. Quantum repeaters can circumvent this ...problem by using quantum memory and entanglement swapping
. As the elementary link of a quantum repeater, the heralded distribution of two-party entanglement between two remote nodes has only been realized with built-in-type quantum memories
. These schemes suffer from the trade-off between multiplexing capacity and deterministic properties and hence hinder the development of efficient quantum repeaters. Quantum repeaters based on absorptive quantum memories can overcome such limitations because they separate the quantum memories and the quantum light sources. Here we present an experimental demonstration of heralded entanglement between absorptive quantum memories. We build two nodes separated by 3.5 metres, each containing a polarization-entangled photon-pair source and a solid-state quantum memory with bandwidth up to 1 gigahertz. A joint Bell-state measurement in the middle station heralds the successful distribution of maximally entangled states between the two quantum memories with a fidelity of 80.4 ± 2.2 per cent (±1 standard deviation). The quantum nodes and channels demonstrated here can serve as an elementary link of a quantum repeater. Moreover, the wideband absorptive quantum memories used in the nodes are compatible with deterministic entanglement sources and can simultaneously support multiplexing, which paves the way for the construction of practical solid-state quantum repeaters and high-speed quantum networks.
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GEOZS, IJS, IMTLJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK, ZAGLJ
Abstract
A quantum key distribution (QKD) system must fulfill the requirement of universal composability to ensure that any cryptographic application (using the QKD system) is also secure. ...Furthermore, the theoretical proof responsible for security analysis and key generation should cater to the number
N
of the distributed quantum states being finite in practice. Continuous-variable (CV) QKD based on coherent states, despite being a suitable candidate for integration in the telecom infrastructure, has so far been unable to demonstrate composability as existing proofs require a rather large
N
for successful key generation. Here we report a Gaussian-modulated coherent state CVQKD system that is able to overcome these challenges and can generate composable keys secure against collective attacks with
N
≈ 2 × 10
8
coherent states. With this advance, possible due to improvements to the security proof and a fast, yet low-noise and highly stable system operation, CVQKD implementations take a significant step towards their discrete-variable counterparts in practicality, performance, and security.
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