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Aiming at the problem of stopping production for communication failure in the belt conveyor protection system, this paper analyzes the characteristics of the query bus and control bus of the protection system, and proposes a grouping communication and bus redundancy mechanism based on the causes and mechanisms of communication failures. The bus redundancy mechanism does not change any hardware and utilizes communication detours to ensure normal communication of the system, at the same time to alert the location and type of failures. By conducting communication tests on 10 devices along the single belt protection system, including multiple failures on the query bus, single failure on the control bus, and composite faults on the query/control bus, the problem of single failure stopping production was solved, and the communication robustness of the system was improved.

Women's leadership continues to change in response to the development of various social changes that occur. This research aims to dig deeper into the communication style of women's leadership in a communication group context, focusing on women leaders in the Universitas Mercu Buana student organization for the 2022/2023 academic year. This research refers to Communication Theory by Sasa Djuarsa Sendjaja which states that leadership styles in groups are divided into five categories, authoritarian style, bureaucratic style, diplomatic style, democratic style, and laissez-faire or group-centered style. With a qualitative case study approach, researchers collect data through data collection and analysis such as in-depth interviews, observation, and documentation. This research uses the constructivism paradigm. In this study, researchers interviewed 5 main key informants and 10 additional informants who are administrators of 5 student organizations active at Universitas Mercu Buana. This research applies Miles and Huberman’s qualitative data analysis technique, then source triangulation is used as a data validity checking technique. The results showed a comprehensive picture of how women leaders in student organizations use their communication styles to give orders, communicate, make decisions, motivate, supervise performance, and lead their group members. The findings show variations in women's leadership communication approaches, with some leaders highlighting assertive leadership, while most lean more towards an inclusive and democratic approach. The researcher can conclude that this study provides a deep insight into the role and contribution of women leaders in group communication, particularly in student organizations. [ABSTRACT FROM AUTHOR]

Komunitas Kerja Remote, or Remote Work Community (KKR), is a community of remote workers, freelancers, and solopreneurs in Indonesia. They actively establish communication to learn together and share information, insights, and experiences while networking and informing about remote job openings on the KKR website, namely www.kamikerjaremote.com. The purpose of the research is to study the communication strategy of the remote work community in Indonesia and convey information on remote job openings to all KKR members in Indonesia. The theory used is group synergy, based on research concepts about group communication, group behaviour, and communication patterns. This research uses a descriptive qualitative method with data acquisition by interview method and documentation sources. The results of the research approach are useful for exploring rich and contextual information and supporting an in-depth interpretation of community reality. So KKR's communication strategy in online communication to establish strengthening and remote job vacancy information has been successful. This can be seen from the activation of KKR members in discussing, exchanging ideas, sharing information, insights, and work experiences as remote workers, as well as the increasing number of job openings on the KKR website. [ABSTRACT FROM AUTHOR]

In recent years, the popularity of blockchain application in healthcare sector has increased manifold due to features such as decentralized architecture, security, immutability and authentication. However, there are some challenges associated with blockchain-based healthcare frameworks. Firstly, blockchain provides data verifiability meaning that anything stored there is accessible to all nodes in the network for verification. However, it is unacceptable for sensitive medical data to be made accessible to everyone. Secondly, healthcare sectors are group-oriented and frequently involve open networks for communication which lead to data breaches and other security risks. Lastly, due to limited size of a block in blockchain, many hospitals prefer storing patient's data locally in a centralized server or opt for cloud storage which have their own threat vectors. In this work, we propose a three-phase unified approach to solve the above problems. Our framework utilizes proxy re-encryption and advanced cryptographic techniques to provide stringent access control. Next, a blockchain-based group encryption is proposed to ensure secure group communication. A group session key will be agreed upon by the authorized group members and used to protect sensitive patient information. Lastly, IPFS-based blockchain data storage is proposed to maintain data securely offsite. We provide a comparative security analysis of the proposed framework with other existing peer models and show that our framework offers several new security features. We also examine the security of the proposed framework using BAN logic. Furthermore, the proposed framework is simulated using the OMNET++ software, and its storage and computation costs are examined to establish its effectiveness. [ABSTRACT FROM AUTHOR]

Multicast services provide an efficient way of conserving resources and reducing network traffic for multicast senders. However, ensuring security, particularly source authentication, is crucial for applications such as online news, IPTV, video streaming, and stock quote distribution. Previous research efforts have attempted to provide source authentication for multicast applications, but they often struggle to handle the dynamic nature of multicast mobile receivers and multi-domain networks. This paper provides an analysis of research conducted over 22 years on source authentication mechanisms with non-repudiation. Most of these mechanisms fail to address the dynamic nature of mobile users and multi-domain networks. To address this issue, a new multicast source authentication scheme for multi-domain Software Defined Mobile Networks (SDMN) is proposed. This approach uses the global view of the controller in SDMN to operate in dynamic environments, provide non-repudiation, and tolerate packet loss. Simulation results indicate that the proposed mechanism uses resources efficiently, reduces communication and delay overhead, and performs well in multi-domain and dynamic networks. [ABSTRACT FROM AUTHOR]

ABSTRACTMulticast services provide an efficient way of conserving resources and reducing network traffic for multicast senders. However, ensuring security, particularly source authentication, is crucial for applications such as online news, IPTV, video streaming, and stock quote distribution. Previous research efforts have attempted to provide source authentication for multicast applications, but they often struggle to handle the dynamic nature of multicast mobile receivers and multi-domain networks. This paper provides an analysis of research conducted over 22 years on source authentication mechanisms with non-repudiation. Most of these mechanisms fail to address the dynamic nature of mobile users and multi-domain networks. To address this issue, a new multicast source authentication scheme for multi-domain Software Defined Mobile Networks (SDMN) is proposed. This approach uses the global view of the controller in SDMN to operate in dynamic environments, provide non-repudiation, and tolerate packet loss. Simulation results indicate that the proposed mechanism uses resources efficiently, reduces communication and delay overhead, and performs well in multi-domain and dynamic networks.

This document is an editorial titled "Mindfulness in interpersonal, group, organization, media, and cross-culture communication" published in Frontiers in Psychology. The editorial explores the application of mindfulness in various communication settings, including interpersonal, group, organizational, media, and cross-cultural contexts. It highlights how mindfulness can enhance understanding and effectiveness in communication by fostering empathy, reducing conflict, improving information consumption and production, and navigating intercultural misunderstandings. The editorial synthesizes insights from four articles featured in the research topic, discussing practical implications and suggesting future research directions. The document emphasizes the transformative power of mindfulness in communication and its potential to improve healthcare, education, cultural understanding, and technological design. [Extracted from the article]

With the flourish of the Internet of Things (IoT), the group communication Constrained Application Protocol (CoAP) emerged at the historic moment, enabling homogeneous devices with constrained computing ability to communicate with ease. CoAP is widely used in transportation, health care and many other aspects. Hence, it is prominent to propose a flexible and efficient architecture for usage in such scenarios and study the data security and consistency of the architecture from the perspective of formal methods. In this paper, we extend the group communication CoAP model to the enhanced group communication CoAP by the introduction of smart gateways and binding to new security suites. We make further improvements to increase the scalability and flexibility of the architecture, making it more applicable in a healthcare scenario or smart home scenario. And we adopt process algebra Communicating Sequential Processes (CSP) with real-time extension to model the enhanced group communication CoAP. We use model checker PAT to verify eight properties of our model on an abstract level, including four basic properties and four security properties. We also conduct a simulation on the local machine for validation of the above properties on a more detailed level. Despite some simplifications of physical properties, both results of the verification and simulation show that the proposed architecture can satisfy those requirements and demonstrate a good possibility of being securely put into service. [ABSTRACT FROM AUTHOR]

Turn-taking is the most basic sequential process in group interactions. However, few studies have analyzed how turn-taking patterns impact group dynamics and outcomes. Research has shown that turn-taking in group interactions usually takes the form of a dyadic ABA pattern, in which two speakers talk interchangeably. In this paper, we propose that in groups discussing a controversial topic (abortion rights), ABA patterns transmit conflict. It was found that ABA patterns correlate with reciprocal exchanges of contradictory arguments, which, when prolonged, escalate into conflicts marked by heightened negativity, dominance, disagreement, and opinion strength. Content in ABA patterns conveyed later in the conversation becomes more conflictive, compared to non-dyadic ordering. The interacting group members in the ABA pattern were less satisfied with the group, as manifested by a lower level of perceived quality of the discussion, and they gave mutual assessments of influence, dissimilarity, and disagreement. [ABSTRACT FROM AUTHOR]

In the technology driven era, automation and communication have attained new heights, which paved the way for an improved human lifestyle. The Internet of Things (IoT) is one of the key aspects of this domain that promises to connect real-world objects embedded with sensors, enable them to communicate, and aid in making informed decisions. However, the growth of technology for convenience has also attracted various attacks on privacy and confidentiality. Numerous classical public-key cryptography based security solutions have been adopted to evade the problems in group communication. Unfortunately, most of the solutions fail to meet computationally lightweight requirements. In this paper, we propose a lightweight NTRU (Nth Degree Truncated Polynomial Ring Units) and Secret Sharing Based Secure Group Communication Scheme that is suitable for low bandwidth communication over the Internet of Medical Things (IoMT), Vehicular Adhoc Networks (VANET) and Precision Agriculture. Theoretical analyses and illustrations demonstrate that the proposed scheme is superior in comparison to the existing schemes.

The Internet of Things or "IoT" determines the highly interconnected network of heterogeneous devices where each type of communication seems to be possible, even unauthorized. Consequently, the security requirement for these networks became crucial, while conventional Internet security protocol was identified as unusable in these types of networks, especially because of some classes of IoT devices with constrained resources. Secure group communication (SGC) in the IoT environment is vital to ensure the confidentiality, integrity, and availability (CIA) of data swapped within a collection of IoT devices. Typically, IoT devices were resource-constrained with limited memory, processing, energy, and power, which makes SGC a difficult task. This article designs a Fully Homomorphic Encryption with Optimal Key Generation Secure Group Communication (FHEOKG-SGC) technique in the IoT environment. The presented FHEOKG-SGC technique mainly focuses on the encryption and routing of data securely in the IoT environment via group communication. To accomplish this, the presented FHEOKG-SGC technique initially designs an FHE-based encryption technique to secure the data in the IoT environment. Next, the keys in the FHE technique are chosen optimally using the sine cosine algorithm (SCA). At the same time, the plum tree algorithm (PTA) is applied for the identification of the routes in the IoT network. Finally, the FHEOKG-SGC technique employs a trust model to improve the secure communication process, and the key management center is used for optimal handling of the keys. The simulation analysis of the FHEOKG-SGC technique is tested using a series of experiments, and the outcomes are studied under various measures. An extensive comparative study highlighted the improvement of the FHEOKG-SGC algorithm over other recent approaches. [ABSTRACT FROM AUTHOR]

Digital child and youth research is often conducted in schools involving minors. Corresponding research designs raise two related sets of problems: Ethical issues with regard to working with vulnerable groups like children and adolescents and access to these groups. The latter pertains to the concept of gatekeeping which is an ethical issue in and of itself if certain groups or areas of research are systematically excluded from empirical research and, consequently, from the resulting benefits. Thus, our study examines how perceived ethical challenges influence gatekeepers’ decisions to grant or deny access to investigate a potentially problematic topic: pupils’ group communication. We addressed this research question empirically via semi-structured in-depth interviews with eight educational gatekeepers in Germany inquiring their attitudes on research in schools in general and on the specific topic of pupils’ group communication via instant messaging as an exemplar of digital child and youth research. Approaching the question from two perspectives (procedural ethics and ethics in practice), we identified hierarchical power structures within multiple levels of gatekeeping and revealed rationales to deny access based on ethical considerations with regard to the given scenario of pupils’ group communication.

This investigation sought to find the relationships among multiple dimensions of personality and multiple features of language style. Unlike previous investigations, after controlling for such other moderators as culture and socio-demographics, the current investigation explored those dimensions of naturalistic spoken language that most closely align with communication. In groups of five to eight players, participants (N = 340) from eight international locales completed hour-long competitive games consisting of a series of ostensible missions. Composite measures of quantity, lexical diversity, sentiment, immediacy and negations were measured with an automated tool called SPLICE and with Linguistic Inquiry and Word Count. We also investigated style dynamics over the course of an interaction. We found predictors of extraversion, agreeableness, and neuroticism, but overall fewer significant associations than prior studies, suggesting greater heterogeneity in language style in contexts entailing interactivity, conversation rather than solitary message production, oral rather than written discourse, and groups rather than dyads. Extraverts were found to maintain greater linguistic style consistency over the course of an interaction. The discussion addresses the potential for Type I error when studying the relationship between language and personality. [ABSTRACT FROM AUTHOR]

This investigation sought to find the relationships among multiple dimensions of personality and multiple features of language style. Unlike previous investigations, after controlling for such other moderators as culture and socio-demographics, the current investigation explored those dimensions of naturalistic spoken language that most closely align with communication. In groups of five to eight players, participants (N = 340) from eight international locales completed hour-long competitive games consisting of a series of ostensible missions. Composite measures of quantity, lexical diversity, sentiment, immediacy and negations were measured with an automated tool called SPLICE and with Linguistic Inquiry and Word Count. We also investigated style dynamics over the course of an interaction. We found predictors of extraversion, agreeableness, and neuroticism, but overall fewer significant associations than prior studies, suggesting greater heterogeneity in language style in contexts entailing interactivity, conversation rather than solitary message production, oral rather than written discourse, and groups rather than dyads. Extraverts were found to maintain greater linguistic style consistency over the course of an interaction. The discussion addresses the potential for Type I error when studying the relationship between language and personality.

The growing pandemic of COVID-19 demands public awareness across the globe for people's health and safety. Accordingly, the government of Indonesia has implemented the PSBB, PPKM, and mandatory vaccination policies. The current study used a descriptive and quantitative approach employing surveys and questionnaires as the main data collection tools. The research was conducted on a group of traders at Pondok Labu Market, South Jakarta, which consisted of five trade groups - clothes, fruit, grocery, vegetables, and gold. Of them, 94 respondents were selected as the study sample. Freire's theory of consciousness and bona fide group theory were followed. The results indicated that by implementing health protocols, awareness continued to process, develop, and expand from the level of "naive awareness" and "critical awareness" to the highest level of "awareness." The limitations noted were the lack of handwashing facilities and hand sanitizers provided to the traders. Although the implementation of PSBB and PPKM has affected the overall business of the traders, they continue to comply with the government protocols. [ABSTRACT FROM AUTHOR]

WeChat is the most impactful social media application in the everyday lives of Chinese citizens today. On the basis of qualitative interviews with Chinese students abroad, this paper discusses various aspects of WeChat group communication, such as social noise, muting and group composition. The theoretical basis is a human-centric approach to ICT adoption, with the understanding that the usage of technology is deeply intertwined with culture, values and everyday social behaviour. Therefore, the body of the discussion takes Chinese cultural concepts such as guanxi (network) and mianzi (face) into account. As a result, a culturally sensitive model of functional and dysfunctional aspects of WeChat communication is developed, connecting the ICT adoption process with Chinese cultural concepts. [ABSTRACT FROM AUTHOR]

Hybrid brainstorming is ecologically more valid than all-interactive or all-noninteractive brainstorming, yet understudied. Although ideational benefits of hybrid groups have been found, studies have rarely focused on its affective/motivational contributions or ability to select ideas. In a randomized experiment, noninteractive-then-interactive (hybrid) groups perceived (1) higher goal clarity, engagement, and task attractiveness, and (2) chose more quality ideas than all-noninteractive groups. Additionally, (3) given the instruction for both hybrid and all-noninteractive conditions to be critical in idea selection, participants individually selected ideas that were more useful, thus overall higher quality, than the nonselected. [ABSTRACT FROM AUTHOR]

The Internet of Things or “IoT” determines the highly interconnected network of heterogeneous devices where each type of communication seems to be possible, even unauthorized. Consequently, the security requirement for these networks became crucial, while conventional Internet security protocol was identified as unusable in these types of networks, especially because of some classes of IoT devices with constrained resources. Secure group communication (SGC) in the IoT environment is vital to ensure the confidentiality, integrity, and availability (CIA) of data swapped within a collection of IoT devices. Typically, IoT devices were resource-constrained with limited memory, processing, energy, and power, which makes SGC a difficult task. This article designs a Fully Homomorphic Encryption with Optimal Key Generation Secure Group Communication (FHEOKG-SGC) technique in the IoT environment. The presented FHEOKG-SGC technique mainly focuses on the encryption and routing of data securely in the IoT environment via group communication. To accomplish this, the presented FHEOKG-SGC technique initially designs an FHE-based encryption technique to secure the data in the IoT environment. Next, the keys in the FHE technique are chosen optimally using the sine cosine algorithm (SCA). At the same time, the plum tree algorithm (PTA) is applied for the identification of the routes in the IoT network. Finally, the FHEOKG-SGC technique employs a trust model to improve the secure communication process, and the key management center is used for optimal handling of the keys. The simulation analysis of the FHEOKG-SGC technique is tested using a series of experiments, and the outcomes are studied under various measures. An extensive comparative study highlighted the improvement of the FHEOKG-SGC algorithm over other recent approaches.

Implementing group communication in a village requires awareness and a sense of belonging among residents so that every goal in developing, maintaining and introducing the village to the wider community can be achieved. This effort can be done by maintaining the culture of mutual cooperation (gotong royong), which has long been inculcated by Indonesians. Even though this culture has long been embedded, there are still many villages that only implement mutual cooperation in one activity, that is a routine community service. There are even residents who do not have awareness and leave the culture of gotong royong. One of the villages in Surabaya city has succeeded in maintaining the culture of gotong royong in the form of group communication to develop its environment into a tourist attraction so that villagers can carry out economic activities independently from their respective homes. [ABSTRACT FROM AUTHOR]

This article provides an overview of how group communication among Punguan Raja Sonang members, namely the association of students with Batak ethnic backgrounds from the clans of Gultom, Samosir, Sitinjak, Pakpahan and Harianja at the University of Bengkulu. Using a qualitative-descriptive approach with data collection methods by observation, in-depth interviews, and documentation, the results show that the members of Punguan Raja Sonang need the closest people that can help them get to know their fellow Bataks in a clan. The same background, area of origin, belief, and language make the members of Punguan Raja Sonang at the University of Bengkulu have cohesiveness or strength to remain in the clan group. In addition, their sense of Batakness is nurtured through group communication, although there are indications that some group members are colonized by certain Batak character stereotypes, which makes them participate in prejudging other group members who have anomalous characters. Above all, a close togetherness among them can create a high sense of solidarity both with older members and with young peers.

Modern internet of things (IoT) applications can benefit from advanced communication paradigms, including multicast and anycast. Next-generation internet architectures, such as information-centric networking (ICN), promise to support these paradigms, but at the same time they introduce new security challenges. This paper presents a solution that extends an ICN-like architecture based on software-defined networking (SDN) that supports those communication paradigms. Using the proposed solution, the underlying architecture is enhanced with a novel security mechanism that allows content “advertisements” only from authorized endpoints. This mechanism prevents “content pollution”, which is a significant security threat in ICN architectures. The proposed solution is lightweight, and it enables identity sharing as well as secured and controlled identity delegation.

Since most Internet of things (IoT) devices are energy-limited, increasingly more manufacturers have chosen to develop IoT applications based on group communication. For these applications, a secure and effective authenticated group secret key is fundamental to whole group communication. A large number of related protocols have been proposed to address this security problem. However, most of them have a centralized architecture, which is vulnerable to a single point of failure. Blockchain technology has the potential to address the challenges mentioned above because of its distributed, secure, and private property. Thus, this paper proposes a blockchain-based authenticated group key agreement protocol for IoT. The proposed protocol introduces a new entity called the device manager, who acts as an intermediary to connect IoT devices with blockchain networks. Security analysis demonstrates the robustness of the proposed protocol to various kinds of attacks. Besides, the simulation results further show that the time costs of protocol operations are reasonable and suitable for IoT environments. [ABSTRACT FROM AUTHOR]

Income redistribution with an efficiency loss is expected to have a twofold negative effect on support for redistribution, as it lowers egoistic support for redistribution and activates efficiency preferences. This study tests whether such a negative relationship exists, increases with the size of efficiency loss and interacts with group communication and the income position. We present a laboratory experiment in which subjects receive a randomly allocated income and must coordinate on a majority tax rate using a deliberative communication tool. The rate of money lost as a part of the redistribution process is manipulated as a treatment variable (0%, 5%, 20%, or 60%). Experimental evidence shows that efficiency loss exerts a robust negative effect on support for redistribution. The effect shows a tipping point pattern, is stronger at the lower end of the income distribution and is not fully explained by egoistic preferences. Inefficiency matters mostly for the chosen tax rate after group communication. At an efficiency loss of 60%, however, group communication does not affect support for redistribution, which implies that inefficiencies tend to play a minor role in the context of redistribution as long as they are within a moderate range. JEL Classification: C91, C92, D63, D72 [ABSTRACT FROM AUTHOR]

Real-world multi-agent tasks often involve varying types and quantities of agents. These agents connected by complex interaction relationships causes great difficulty for policy learning because they need to learn various interaction types to complete a given task. Therefore, simplifying the learning process is an important issue. In multi-agent systems, agents with a similar type often interact more with each other and exhibit behaviors more similar. That means there are stronger collaborations between these agents. Most existing multi-agent reinforcement learning (MARL) algorithms expect to learn the collaborative strategies of all agents directly in order to maximize the common rewards. This causes the difficulty of policy learning to increase exponentially as the number and types of agents increase. To address this problem, we propose a type-based hierarchical group communication (THGC) model. This model uses prior domain knowledge or predefine rule to group agents, and maintains the group's cognitive consistency through knowledge sharing. Subsequently, we introduce a group communication and value decomposition method to ensure cooperation between the various groups. Experiments demonstrate that our model outperforms state-of-the-art MARL methods on the widely adopted StarCraft II benchmarks across different scenarios, and also possesses potential value for large-scale real-world applications. [ABSTRACT FROM AUTHOR]

Digital media creates a gap in the definition of the communication context created by West Turner (2010). Situational boundaries are increasingly unclear when in the whole process the number of participants, distance, space, feedback, media functions, and variety of channels are integrated. This study aims to analyze the implications of digital media functions in elaborating interpersonal communication to successfully mobilize groups. The study was conducted by reviewing the literature on new digital media theories. As a result, connectedness occurs as a character of interpersonal communication in digital new media. When these context is elaborated by digital media so that integrating more participants, interaction is not just merely connection anymore, but focuses on shared meaning. At this point the context is shifted into group communication. Keywords : new digital media, communication context, interpersonal communication, group communication

• We test the effects of utterance interaction on rapport in cognitive communication. • Turn-taking and vocal pitch synchrony during group creative task is evaluated. • Amount of turn-taking is positively correlated to subjective rapport. • Vocal pitch synchrony and amount of utterances are not related to rapport. Previous studies have suggested that in emotionally-oriented communication such as counseling and casual conversation, non-verbal communication characteristics such as turn-taking and vocal pitch synchrony were related to formation of rapport. However, in cognitive goal-oriented communication such as group problem-solving, there are few studies investigating whether the features of non-verbal communication cues correlate with rapport. In this research, we focused on the turn-taking and vocal pitch synchrony during creative problem-solving communication, and investigated their possible relationship with rapport. We adopted the Alternative Uses Tasks (AUT) as the case of cognitive goal-oriented communication, which measures individual creativity, and reorganized it to a group communication task. In the experiment, groups of three people each with the same gender discussed ideas for unusual uses of daily necessities for 20 minutes. The number of utterances which were responsive to the utterance of other speaker was used as an indicator of turn-taking, and the mean value of difference of the vocal pitch between the participant's was used as an indicator of vocal pitch synchrony. Multiple regression analysis showed that turn-taking, rather than total utterances, were significantly positively correlated with rapport, while vocal pitch synchrony did not contribute to rapport explanations. The results suggest that in the creative problem-solving discussion, the more turn-taking the conversation has, the more you feel rapport. The discrepancy with the previous study may suggest that the vocal pitch synchrony contribute to rapport in emotionally-oriented communication, but the vocal pitch synchrony would be not so relevant in forming rapport in more cognitive goal-oriented communication. In conclusion, the amount of turn-taking is a reliable non-verbal predictor of rapport, even in cognitive goal-oriented communication. [ABSTRACT FROM AUTHOR]

The comprehensive review synthesizes 64 empirical studies on communication and transactive memory systems (TMS). The results reveal that (a) a TMS forms through communication about expertise; (b) as a TMS develops, communication to allocate information and coordinate retrieval increases, promoting information exchange; and (c) groups update their TMS through communicative learning. However, direct interpersonal communication is not necessary for TMS development or utilization. Nor do high-quality information-sharing processes always occur within developed TMS structures. For future research, we propose a multidimensional network approach to TMS that incorporates technologies, addresses member characteristics, considers multiple communication types, and situates groups in context. [ABSTRACT FROM AUTHOR]