Centralized Communication Network Research Articles

Unveiling the Impact of Communication Network on Engineering Project Team Performance: The Interplay of Centralization and Tie Strength.

Recent research has focused on the impact of communication networks on the performance of construction project teams, attempting empirical exploration from various social network analysis perspectives. However, there is still a significant gap in understanding the variations in performance and the mechanisms for teams using different communication networks. Drawing from organizational learning theory and social network theory, this study, based on the Input-Mediator-Output (IMO) model, explores the effects of the interaction between centralization and tie strength in communication networks on team performance, as well as the mediating mechanisms of knowledge sharing behavior and team resilience performance in engineering project teams. Drawing on classic group communication experiment, we design an online communication and collaboration platform to simulate the execution of a construction engineering project. Finally, data was collected through the communication experiment with 720 participants, and hypotheses were tested using ANOVA and PROCESS. The results indicate that under conditions of weak tie strength, centralized communication networks yield higher performance. Conversely, under conditions of strong tie strength, decentralized communication networks demonstrate superior performance. Furthermore, this study also verifies the mediating role of knowledge sharing behavior and team resilience performance when tie strength is strong. This study focuses on engineering project team, exploring the evolutionary development of knowledge sharing behavior and team resilience performance from the perspective of the interaction of communication network structural characteristics, as well as the paths to enhancing team performance. Our research results highlight the interactive effects of structural indicators and relational indicators of communication networks, revealing the mechanism by which the structure of communication networks impacts team performance. Additionally, from the perspectives of forming and timely adjusting team communication models, and motivating and supporting employee communication behavior, our study provides practical insights for project managers and relevant administrators.

The Interactive Effects of Communication Network Structure and Organizational Size on Task Performance in Project-Based Organizations: The Mediating Role of Bootleg Innovation Behavior

A PBO is a temporary organization formed by assembling members with diverse experiences and backgrounds, aimed at achieving specific innovation goals. Constructing a reasonable communication network structure and enhancing organizational synergy are effective ways to promote the sustainable development of the system. This study, based on the Input–Process–Output (IPO) model and social network analysis, utilized a group collaboration platform to conduct a three-stage communication experiment on 685 construction project managers. Under two organizational sizes, the internal mechanism of how communication networks with two levels of centralization influence task performance were tested. The results indicate that in the case of a smaller organizational size, PBOs using a decentralized communication network tend to achieve higher task performance. However, as the organizational size expands, PBOs employing a centralized communication network may surpass in task performance. Additionally, we found that with the expansion of organizational size, bootleg innovation behaviors of organizational members are continually stimulated, further enhancing collective task performance. This study, based on the evolution of communication network parameters, explores the structural characteristics of organizational communication networks and the mechanisms underlying the emergence of bootleg innovation behaviors. It delineates the key pathways for improving collective task performance. The findings can provide a scientific reference for the organizational evolution and development of engineering project management.

Communication networks and team performance: selecting members to network positions.

This study examines how individuals come to occupy communication network positions and the effect of selection processes on group performance. Drawing on the Carnegie perspective and research on communication networks, we compare the performance of groups whose members receive their choice of who occupies which network position to the performance of groups whose members do not receive their choice. We integrate ideas from the Carnegie perspective with the social psychological literature on the recognition of expertise to theorize that when group members choose who occupies which network positions, individuals select themselves and others into network positions that best suit their skillsets. The selection process allows groups to match individual member expertise to network position, thereby improving performance. We test this hypothesis in a laboratory study manipulating how members are assigned to positions in a centralized communication network. We find individuals who communicate more during training are more likely to be chosen as the central member, and that their communication activity explains the effect of choosing the central member on performance. Supplemental analyses suggest that groups allowed to select their central member performed as well as, and often better than, groups whose central member was randomly assigned. Our results contribute to the Carnegie perspective by demonstrating that the intra-team processes that develop a team's network help explain their performance.

Expression and biological function of the cellular communication network factor 5 (CCN5) in primary liver cells

The cellular (centralized) communication network (CCN) factor protein family contains six small secreted cysteine-rich proteins sharing high structural similarity. These matricellular proteins have vital biological functions in cell adhesion, migration, cell cycle progression, and control of production and degradation of extracellular matrix. However, in liver the biological functions of CCN proteins become most visible during hepatic injury, disease, and remodeling. In particular, most of the hepatic functions of CCN proteins were derived from CCN2/CTGF, which becomes highly expressed in damaged hepatocytes and acts as a profibrogenic molecule. On the contrary, CCN1/CYR61 seems to have opposite effects, while the biological activity during hepatic fibrosis is somewhat controversially discussed for other CCN family members. In the present study, we analyzed the expression of CCN5/WISP2 in cultures of different types of primary liver cells and in an experimental model of hepatic fibrosis. We found that CCN5 is expressed in hepatic stellate cells, myofibroblasts and portal myofibroblasts, while CCN5 expression is virtually absent in hepatocytes. During hepatic fibrogenesis, CCN5 is significantly upregulated. Overexpression of CCN5 in portal myofibroblasts reduced expression of transforming growth factor-β receptor I (ALK5) and concomitant Smad2 activation, whereas JunB expression is upregulated. Moreover, elevated expression of CCN5 induces endoplasmic reticulum stress, unfolded protein response and apoptosis in portal myofibroblasts. We suggest that upregulated expression of CCN5 might be an intrinsic control mechanism that counteracts overshooting fibrotic responses in profibrogenic liver cells.Graphical abstract

Intelligent Bi-modal Timetable-aware Biometric Attendance System for Enhanced Classroom Attendance

Attendance management is integral to many organizations and academic institutions. The manner in which attendance is managed has evolved over the years encompassing various techniques and methodologies. Although significant improvements have been made, existing systems are mostly standalone systems without proper monitoring and control from a central point. This makes it difficult for several attendance devices to be linked by a common scheme like a timetable schedule. This is integral because the lives of students in every academic institution revolves around a schedule of events and classes. There is also a need to maximize the use of the data generated from attendance systems to make meaningful decisions and predictions about students’ academic activities. The research led to the implementation of several modules which includes the key timetable-schedule module and an elaborate API structure deployed to a central server for a centralized communication network between attendance devices instead of standalone devices as traditional systems have employed. The research also investigates factors affecting the performance of students and which of these factors is the greater determinant. From the results and dataset investigated, it was found that attendance is in fact not the primary determinant of students’ academic performance. Extra educational support, extra-curricular activities and family support are the top ranked factors affecting academic performance in accordance with the results obtained from this work.

Coordination of Multiple Robotic Vehicles in Obstacle-Cluttered Environments

In this work, we consider the motion control problem for a platoon of unicycle robots operating within an obstacle-cluttered workspace. Each robot is equipped with a proximity sensor that allows it to perceive nearby obstacles as well as a camera to obtain its relative position with respect to its preceding robot. Additionally, no robot other than the leader of the team is able to localize itself within the workspace and no centralized communication network exists, i.e., explicit information exchange between the agents is unavailable. To tackle this problem, we adopt a leader–follower architecture and propose a novel, decentralized control law for each robot-follower, based on the Prescribed Performance Control method, which guarantees collision-free tracking and visual connectivity maintenance by ensuring that each follower maintains its predecessor within its camera field of view while keeping static obstacles out of the line of sight for all time. Finally, we verify the efficacy of the proposed control scheme through extensive simulations.

Distributed Control Strategy for Low-Voltage Three-Phase Four-Wire Microgrids: Consensus Power-Based Control

Most of the distributed control strategies for grid-connected power converters are droop-based approaches composed of converters driven in voltage-control mode, based on local and shared data with adjacent units. They are usually combined with consensus protocols to deal with the trade-off between power sharing accuracy and voltage/frequency regulation. To achieve the desired results these control systems usually incorporate other techniques and need to take into account details of primary control dynamic. Additionally, power flow control and current unbalance compensation at the PCC are rarely addressed in such approaches. Contrariwise, the centralized control strategy power-based control has been successful in achieving these functionalities. It is oriented to a set point selection to the whole system, considering converters driven in current-control mode and a central converter in voltage-control mode. However, the dependence on centralized communication network in this method still requires improvement. Thereby, the complementary features of both strategies are combined herein in the consensus power-based control, based on a master/slave peer-to-peer integration using sparse communication. This model-free approach provides all aforementioned benefits to the grid without any other technique. Implementation complexity and costs are decreased, while the flexibility and reliability are enhanced. All these achievements are demonstrated by simulation results under different operational conditions and compared to previous works.

Design of intelligent surveillance system based on wireless ad-hoc network under special conditions

For oil fields, shooting target range, military forbidden zones and other special complex scenarios, it is not only difficult to deploy communication infrastructure because of its remote location and difficult environment, but also difficult to transmit surveillance video images to command stations in real time through centralized communication networks. Furthermore, there is a waste of bandwidth resources and the use of wireless ad hoc networks to transmit surveillance video. Therefore, we aim at designing and implementing a real-time intelligent surveillance system based on wireless ad-hoc networks in special scenes in this project. The system is supposed to capture the video frames of the monitored area and perform automatic intrusion detection. Only when an intrusion is detected, the video frame is encoded and transmitted together with the alarm message to the command center. An improved Yolov2 algorithm to achieve real time object detection on a computationally limited platform was proposed first. A wireless ad-hoc communication system was designed and implemented on the basic of the Tactical Targeting Network Technology (TTNT) Data Link to transmit surveillance video stream, control signaling and alarm message. Then the extensive experiments were conducted to evaluate the system in terms of detection accuracy and communication performance. The experiments results demonstrate the effectiveness and accuracy of the proposed system, the size of the model is only 7.6% of Yolov2 and the detection speed is increased 4 times. This design transforms long-time data transmission into burst data transmission, thus saving bandwidth resources and improving bit error rate of 96.9%. It is of great significance for the future application of artificial intelligence and machine learning in the field of communication

The Paradox of Interaction: Communication Network Centralization, Shared Task Experience, and the Wisdom of Crowds in Online Crowdsourcing Communities

Research on the wisdom of crowds (WOC) identifies two paradoxical effects of communication. The social influence effect hampers the WOC, whereas the collective learning effect improves crowd wisdom. Yet it remains unclear under what conditions such communication impedes or enhances collective wisdom. The current study examined two features characterizing communication in online communities, communication network centralization and shared task experience, and their effect on the WOC. Both these features can serve as indicators of the likelihood that underlying communication may facilitate either social influence or collective learning. With an 8-year longitudinal behavioral-trace data set of 269,871 participants and 1,971 crowds, we showed that communication network centralization negatively affected the WOC. By contrast, shared task experience positively predicted the WOC. Shared task experience also moderated the effect of communication network centralization such that centralized communication networks became more beneficial for crowd performance as shared task experience increased.

Distributed Resilient Adaptive Control of Islanded Microgrids Under Sensor/Actuator Faults

To compensate for the voltage and frequency deviations caused by the droop control in islanded microgrids (MGs), employing an additional control level, called the secondary control, is necessary. Therefore, distributed control methods based on the sparse communication network, are recently employed in secondary control of MGs, because they are more reliable and flexible. However, traditional methods use the centralized communication network, which is neither economical nor efficient due to its large communication burden. Distributed control methods solve many challenges in the secondary layer of MGs, such as disturbances, uncertainties, unmodelled dynamics, noises, delays, attacks, and actuator faults. This paper proposes the novel resilient adaptive consensus-based voltage and frequency control protocols to compensate for the adverse effects of both sensor and actuator faults in communication network channels of islanded MGs. To this end, local adaptive sensor and actuator compensators eliminate the adverse effects of failures on sensors and actuators. The robust stability analysis based on the Lyapunov analysis is given to validate the results. Finally, the understudy islanded MG system is built in MATLAB/SimPowerSystems to verify the theoretical results. It is shown that the proposed secondary control strategies based on the adaptive protocols can highly increase the reliability and resiliency of the MG system compared with the existing distributed resilient methods.

The impact of virtual mirroring on customer satisfaction

We investigate the impact of a novel method called “virtual mirroring” to promote employee self-reflection and impact customer satisfaction. The method is based on measuring communication patterns, through social network and semantic analysis, and mirroring them back to the individual. Our goal is to demonstrate that self-reflection can trigger a change in communication behaviors, which lead to increased customer satisfaction. We illustrate and test our approach analyzing e-mails of a large global services company by comparing changes in customer satisfaction associated with team leaders exposed to virtual mirroring (the experimental group). We find an increase in customer satisfaction in the experimental group and a decrease in the control group (team leaders not involved in the virtual mirroring process). With regard to the individual communication indicators, we find that customer satisfaction is higher when employees are more responsive, use a simpler language, are embedded in less centralized communication networks, and show more stable leadership patterns.

Frequency Regulation by Distributed Secondary Loads on Islanded Wind-Powered Microgrids

Frequency regulation is critical to the successful operation of remote wind–diesel electrical grids. When the grid is in ‘wind–diesel’ mode, frequency regulation is (classically) the sole duty of the diesel electric generator (DEG). An alternative approach is proposed whereby responsibility for frequency regulation is shared by the DEG and a network of autonomous distributed secondary loads (DSLs) consisting of electric thermal storage (ETS) devices. This allows surplus wind to be distributed to residential consumers (as space heat) without the need for a centralized communication network. Numerical modeling of system dynamics with active DSLs is conducted using a SIMULINK wind–diesel hybrid test bed model. The effects of controller gain, installed capacity, switching time and unit coordination timing on frequency and voltage regulation is explored. It is shown that the DSLs can improve frequency regulation in wind–diesel mode while providing storable thermal energy to distributed consumers.

The Researches on the Construction of the Management in Integrated Electric Power Communication Network System

With the extensive construction of integrated network management system for electric power communication, the practical level of construction has become a key factor on its effective. This article analyzes the advantage and necessity of the construction of integrated centralized power communication network management system, review and summarize the electrical communication in real-time operation, maintenance management, operating mode management, professional management, the integrated management and control needs, professional collaborative management six aspects of the functional requirements analysis, elaborate communication network management system application exploration and research, and the future utility of the road overall construction ideas.

CCN proteins: A centralized communication network

The CCN family of proteins includes six members presently known as CCN1, CCN2, CCN3, CCN4, CCN5 and CCN6. These proteins were originally designated CYR61, CTGF, NOV, and WISP-1, WISP-2, WISP-3. Although these proteins share a significant amount of structural features and a partial identity with other large families of regulatory proteins, they exhibit different biological functions. A critical examination of the progress made over the past two decades, since the first CCN proteins were discovered brings me to the conclusion that most of our present knowledge regarding the functions of these proteins was predicted very early after their discovery. In an effort to point out some of the gaps that prevent us to reach a comprehensive view of the functional interactions between CCN proteins, it is necessary to reconsider carefully data that was already published and put aside, either because the scientific community was not ready to accept them, or because they were not fitting with the « consensus » when they were published. This review article points to avenues that were not attracting the attention that they deserved. However, it is quite obvious that the six members of this unique family of tetra-modular proteins must act in concert, either simultaneously or sequentially, on the same sites or at different times in the life of living organisms. A better understanding of the spatio-temporal regulation of CCN proteins expression requires considering the family as such, not as a set of single proteins related only by their name. As proposed in this review, there is enough convincing pieces of evidence, at the present time, in favor of these proteins playing a role in the coordination of multiple signaling pathways, and constituting a Centralized Communication Network. Deciphering the hierarchy of regulatory circuits involved in this complex system is an important challenge for the near future. In this article, I would like to briefly review the concept of a CCN family of proteins and critically examine the progress made over the past 10years in the understanding of their biological functions and involvement in both normal and pathological processes.

Heuristics for the multi-level capacitated minimum spanning tree problem

The capacitated minimum spanning tree (CMST) problem is fundamental to the design of centralized communication networks. In this paper we consider the multi-level capacitated minimum spanning tree problem, a generalization of the well-known CMST problem. Based on work previously done in the field, three heuristics are presented, addressing unit and non-unit demand cases. The proposed heuristics have been also integrated into a mixed integer programming solver. Evaluation results are presented, for an extensive set of experiments, indicating the improvements that the heuristics bring to the particular problem.

Communication in Natural Resource Management: Agreement between and Disagreement within Stakeholder Groups

Communication among stakeholders is commonly held to improve agreement on facts and management goals. Results from statistical network analyses of six natural resource management systems indicate that the effects of communication depend on context. If communication affects stakeholder knowledge and values, it fosters agreement between stakeholder groups but it results in more disagreement within stakeholder groups. In addition, more centralized communication networks have more disagreement, especially within stakeholder groups, while co-management systems have more disagreement between stakeholder groups. The results may reflect communication effects but also selection effects: the propensity of stakeholders or management systems to establish communication ties between participants with dissimilar knowledge and values. In addition, the results may be linked to different phases in the management process. The conclusion includes a reflection on the need for further research to address these possibilities.

A Lagrangian Based Heuristic for the Design of Multipoint Linkages in a Communication Network with Unreliable Links and Node Outage Costs

This paper studies the capacitated minimal spanning tree with unreliable links and node outage costs problem. Tree topologies appear in the design of centralized communication networks. In these topologies the number of nodes in a subtree rooted at the central node is limited to a predefined number due to polling, loading, and response time restrictions. The links in a communication network are prone to failure. Whenever a link in these networks fails all the terminal nodes connected to the central node through that link are unable to communicate till the faulty link is repaired. In some networks such failures can have adverse economic effect on the network user. The economic effect on the network user due to inability of a terminal to communicate with the central node due to link failure is called node outage cost. The sum of expected yearly node outage costs for a network depends on the topology of the network. In this paper we suggest a Lagrangean based heuristic to solve the integer programming formulation of the network topology problem. The objective of the problem is to minimize the sum of link costs and node outage costs. Our computational results on a set of test data with up to 80 nodes show that compared to the previously developed greedy heuristic, our method gives solution that are better by up to 6 percent. The gaps between our heuristic solutions and the lower bounds found as a byproduct of the solution procedure are in the 2–17 percent range.

Conduit and cable installation for a centralized network with logical star-star topology

Addresses a comprehensive design issue of a centralized communication network with logical star-star topology: each established hub is connected to the center node via its own cable route which may pass through a number of sites, and so is the connection from a user to its destination hub. The study distinguishes itself from other network design studies in the literature by explicitly addressing the reality that the cable can be installed only in the conduit, and some hub devices such as line concentrators and multiplexers, if properly installed, would provide more economical cable paths. A cost minimization model is first made to cover three types of decisions in one setting: locating hubs, placing conduit system, and installing cable therein. It is then formulated as a variant of classical network design model, allowing the incorporation of the well-known dual-ascent solution strategy. Despite the complexity inherent to the design problem, the performance of the proposed solution heuristic is shown via the extensive computational experiments with large-scale test problems to be very satisfactory in both speed and quality of the solutions generated.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Topological design of a centralized communication network with unreliable links and node outage costs

In this paper, we present a mathematical formulation of a terminal layout problem in the design of a centralized communication network with unreliable links and node outage costs. The node outage cost associated with a terminal node is a cost incurred by the network user whenever that terminal node is unable to communicate with the central node due to failure of a link. We suggest a two-phase heuristic with a time complexity of O( N 3) to solve the problem. We also present a Lagrangean relaxation method to find the lower bound of the objective function value. The lower bound given by the Lagrangean relaxation method is used to estimate the quality of the solution given by the two-phase heuristic. Experimental results over a wide range of problem structures show that the average solution given by the two-phase heuristic is within 10% of the optimal objective function value.

Uncertainty, Potential Power, and Nondecisions

The sheer existence of a power structure prevented or delayed attempts to redress inequity in an experimental study of redistributive agendas. A's potential power over B suppressed attempts to change a centralized communication network that caused inequity even though A, at the center of the network, expressed no preferences, promised no rewards, threatened no penalties, and did not actually penalize attempts at change. Structure did not automatically determine outcomes; rather, its effect was due to perceptions of power and expectations for the use of power. Yet the issue of inequity was suppressed («nondecided»), even though A's reactions were uncertain. Subjects did not know the amount or probability of reward for nondecisions or the penalty for attempts to change the structure of the communication network