Short-Range Underwater Acoustic Communication Networks

This chapter discusses the development of a short range acoustic communication channel model and its properties for the design and evaluation of MAC (Medium Access Control) and routing protocols, to support network enabled Autonomous Underwater Vehicles (AUV). The growth of underwater operations has required data communication between various heterogeneous underwater and surface based communication nodes. AUVs are one such node, however, in the future, AUV’s will be expected to be deployed in a swarm fashion operating as an ad-hoc sensor network. In this case, the swarm network itself will be developed with homogeneous nodes, that is each being identical, as shown in Figure 1, with the swarm network then interfacing with other fixed underwater communication nodes. The focus of this chapter is on the reliable data communication between AUVs that is essential to exploit the collective behaviour of a swarm network

Innovating communication in the age of digital agriculture.

Introduction. New technologies and science communication at Embrapa: Digital revolution and network communication; Communication for innovation. Communication results and challenges in the digital age. Educommunication to support collective creation. Dialogical communication to support sustainable development and popularization of science. Final considerations

The Cognitive Virtues of Dynamic Networks

For the most part, studies in the network science literature tend to focus on networks whose functional connectivity is largely invariant with respect to some episode of collective information processing. In the real world, however, networks with highly dynamic functional topologies tend to be the norm. In order to improve our understanding of the effect of dynamic networks on collective cognitive processing, we explored the problem-solving abilities of synthetic agents in dynamic networks, where the links between agents were progressively added throughout the problem-solving process. The results support the conclusion that (at least in some task contexts) dynamic networks contribute to a better profile of problem-solving performance compared to static networks (whose topologies are fixed throughout the course of information processing). Furthermore, the results suggest that constructive networks (like those used in the present study) strike a productive balance between autonomy and social influence. When agents are allowed to operate independently at the beginning of a problem-solving process, and then later allowed to communicate, the result is often a better profile of collective performance than if extensive communication had been permitted from the very outset of the problem-solving process. These results are relevant, we suggest, to a range of phenomena, such as groupthink, the common knowledge effect and production blocking, all of which have been observed in group problem-solving contexts

The Use of Information and Communication Technology (ICT) in Managing High Arctic Tourism Sites: A Collective Action Perspective

Sustainable management of nature-based tourism sites is a pertinent issue in vulnerable Arctic environments. Arctic tourism operators often act collectively to protect their common interests of ensuring the sustainability of tourism sites. Nowadays, information and communication technology (ICT) is increasingly used to support these collaborative efforts, but the remoteness and risks associated with Arctic tourism operations challenge the success of such collective action. This study explores the use of ICT as a management tool for Arctic tourism sites to ensure their sustained quality. Drawing on a case study of an expedition cruise operators’ network in Svalbard, we explore how the use of ICT affects collective action and sustainable management of tourism sites. Our findings show that, through increased noticeability, the creation of artificial proximity and the development of new management practices, ICT can help to overcome the challenges for collective action that are posed by the Arctic environment. The use of ICT results in changes in a network’s relational and normative structures, which can as much add to as detract from the success of collective action. Our study indicates that the successful application of ICT depends on a high level of social capital, in particular norms, to guide interactions between ICT and network actors

Social Media, Digital Activism, and Online Collective Action:_x000D_ A Tale of Two Overlapping Women\u27s Rights Movements

Research on collective action (CA) dates back to at least the 1960s. However, the plethora of Internet-driven CAs warrants the need to revisit the theory of CA. By analyzing blog and Twitter postings for the two movements, “Women to Drive” and “Sexual Harassment”, we - (1) develop novel methodologies to model online CAs by utilizing existing CA theories and computational approaches for social network analysis, sentiment analysis, text mining, and content analysis, (2) establish a rigorous and fundamental analytical framework to understand the emergence, evolution, development and trajectory of CAs in complex online environments, and (3) study coalition formation, interorganizational communication, and transnational support of the two online CAs. The study also identifies cross-cultural aspects of the campaign network, where Arabic hashtags relate to the local factors and English hashtags connect with transnational and interorganizational support from various organizations such as human rights and women’s rights

Adaptive foraging in dynamic environments using scale-free interaction networks

Group interactions are widely observed in nature to optimize a set of critical collective behaviors, most notably sensing and decision making in uncertain environments. Nevertheless, these interactions are commonly modeled using local (proximity) networks, in which individuals interact within a certain spatial range. Recently, other interaction topologies have been revealed to support the emergence of higher levels of scalability and rapid information exchange. One prominent example is scale-free networks. In this study, we aim to examine the impact of scale-free communication when implemented for a swarm foraging task in dynamic environments. We model dynamic (uncertain) environments in terms of changes in food density and analyze the collective response of a simulated swarm with communication topology given by either proximity or scale-free networks. Our results suggest that scale-free networks accelerate the process of building up a rapid collective response to cope with the environment changes. However, this comes at the cost of lower coherence of the collective decision. Moreover, our findings suggest that the use of scale-free networks can improve swarm performance due to two side-effects introduced by using long-range interactions and frequent network regeneration. The former is a topological consequence, while the latter is a necessity due to robot motion. These two effects lead to reduced spatial correlations of a robot's behavior with its neighborhood and to an enhanced opinion mixing, i.e., more diversified information sampling. These insights were obtained by comparing the swarm performance in presence of scale-free networks to scenarios with alternative network topologies, and proximity networks with and without packet loss

EIES 2 : a distributed architecture for supporting group work

The Computerized Conferencing Center (CCCC) at New Jersey Institute of Technology (NJIT) has been researching on-line group communications for 17 years by developing and studying tools to advance the collective intelligence . The Electronic Information Exchange System 2 (EIES2) provides a research, development and operational environment for distributed computer supported cooperative work (CSCW) systems. The EIES 2 distributed Smalltalk processor provides for rapid prototyping and implementation of muti-media CSCW facilities in the network environment. The Smalltalk support of the object model, and meta-language properties make it ideally suited for incremental development CSCW applications. The EIES2 communication environment supports a decentralized network architecture. Modern standards are used in the implementation of data structures, communication interfaces and database. The EIES2 application layer protocols support use ASN.1 data representation to access to an object-oriented distributed database via X.ROS remote operation services. EIES2 can serve as a foundation on which group work systems may be built and defines protocols that can allow them to inter-operate. An initial system presents a powerful metaphor of conferences and activities which provides an extensible framework upon which to add group work applications. Work to date has provided structures for information exchange, inquiry networking, information filtering, the on-line virtual classroom, and group decision support. This paper presents the system architecture model used for EIES2 and describes the implementation and current applications