The Impact of Network Connectivity on Collective Learning

Despite the recognised effectiveness of networks of marine protected areas (MPAs) as a biodiversity conservation instrument, MPA network design frequently disregards the importance of connectivity patterns. In the case of sedentary marine populations, connectivity stems not only from the stochastic nature of the physical environment that affects dispersal of early life stages, but also from the spawning stock attributes that affect reproductive output (e.g. passive eggs and larvae) and survivorship. Early life stages are virtually impossible to track in the ocean. Therefore, numerical ocean current simulations coupled with egg and larval Lagrangian transport models remain the most common approach for the assessment of marine larval connectivity. Inferred larval connectivity may differ depending on the type of connectivity considered; consequently, the prioritisation of sites for the conservation of marine populations might also differ. Here, we introduce a framework for evaluating and designing MPA networks based on the identification of connectivity hotspots using graph theoretic analysis. As a case study, we used a network of open-access areas and MPAs off Mallorca Island (Spain), and tested its effectiveness for the protection of the painted comber Serranus scriba. Outputs from network analysis were used to (1) identify critical areas for improving overall larval connectivity, (2) assess the impact of species’ biological parameters in network connectivity and (3) explore alternative MPA configurations to improve average network connectivity. Results demonstrate the potential of graph theory to identify non-trivial egg/larval dispersal patterns and emerging collective properties of the MPA network, which are relevant for increasing protection efficiency.

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Antiepileptic Efficacy and Network Connectivity Modulation of Repetitive Transcranial Magnetic Stimulation by Vertex Suppression

Frontiers in Human Neuroscience ◽

10.3389/fnhum.2021.667619 ◽

2021 ◽

Vol 15 ◽

Author(s):

Cong Fu ◽

Aikedan Aisikaer ◽

Zhijuan Chen ◽

Qing Yu ◽

Jianzhong Yin ◽

...

Keyword(s):

Transcranial Magnetic Stimulation ◽

Seizure Frequency ◽

Magnetic Stimulation ◽

Repetitive Transcranial Magnetic Stimulation ◽

Reduction Rate ◽

Network Connectivity ◽

Hamilton Depression Scale ◽

Depression And Anxiety ◽

Epileptiform Discharges ◽

The Impact

A core feature of drug-resistant epilepsy is hyperexcitability in the motor cortex, and low-frequency repetitive transcranial magnetic stimulation (rTMS) is a suitable treatment for seizures. However, the antiepileptic effect causing network reorganization has rarely been studied. Here, we assessed the impact of rTMS on functional network connectivity (FNC) in resting functional networks (RSNs) and their relation to treatment response. Fourteen patients with medically intractable epilepsy received inhibitive rTMS with a figure-of-eight coil over the vertex for 10 days spread across two weeks. We designed a 6-week follow-up phase divided into four time points to investigate FNC and rTMS-induced timing-dependent plasticity, such as seizure frequency and abnormal interictal discharges on electroencephalography (EEG). For psychiatric comorbidities, the Hamilton Depression Scale (HAM-D) and the Hamilton Anxiety Scale (HAM-A) were applied to measure depression and anxiety before and after rTMS. FNC was also compared to that of a cohort of 17 healthy control subjects. The after-effects of rTMS included all subjects that achieved the significant decrease rate of more than 50% in interictal epileptiform discharges and seizure frequency, 12 (14) patients with the reduction rate above 50% compared to the baseline, as well as emotional improvements in depression and anxiety (p < 0.05). In the analysis of RSNs, we found a higher synchronization between the sensorimotor network (SMN) and posterior default-mode network (pDMN) in epileptic patients than in healthy controls. In contrast to pre-rTMS, the results demonstrated a weaker FNC between the anterior DMN (aDMN) and SMN after rTMS, while the FNC between the aDMN and dorsal attention network (DAN) was greater (p < 0.05, FDR corrected). Importantly, the depressive score was anticorrelated with the FNC of the aDMN-SMN (r = −0.67, p = 0.0022), which was markedly different in the good and bad response groups treated with rTMS (p = 0.0115). Based on the vertex suppression by rTMS, it is possible to achieve temporary clinical efficacy by modulating network reorganization in the DMN and SMN for patients with refractory epilepsy.

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Testing the Impact of Road Network Connectivity on Criminal Lethality

Homicide Studies ◽

10.1177/1088767918754307 ◽

2018 ◽

Vol 22 (3) ◽

pp. 277-295 ◽

Cited By ~ 2

Author(s):

Aaron C. Poole ◽

James C. McCutcheon ◽

Kayla Toohy ◽

Bert Burraston

Keyword(s):

Road Network ◽

Reporting System ◽

Explanatory Variable ◽

Network Connectivity ◽

Google Earth ◽

Community Survey ◽

Data Sources ◽

American Community Survey ◽

Positive Outcomes ◽

The Impact

Increased road network connectivity has been linked to more positive outcomes among all health outcomes. Road network connectivity has yet to be tested in association with specifically criminal lethality. The current study looks to incorporate road network connectivity as an explanatory variable for criminal lethality. Data on Road Network Connectivity and Criminal Lethality are gathered for 190 cities. Data sources include the National Incident-Based Reporting System (NIBRS), 2010 Census, 2010 American Community Survey, Google Earth, and Census Topologically Integrated Geographic Encoding and Referencing (TIGER) files. The data demonstrate that a city’s road network connectivity is related to decreases in the rates of lethality among assaults. Implications of this finding are discussed.

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The Impact of Technology Advances on Strategy Formulation in Mobile Communications Networks

Mobile Commerce ◽

10.4018/978-1-59140-044-8.ch006 ◽

2011 ◽

pp. 90-120

Author(s):

Ioanna D. Constantiou ◽

George C. Polyzos

Keyword(s):

Technological Innovation ◽

Mobile Communications ◽

Network Connectivity ◽

Strategy Formulation ◽

Communications Networks ◽

Wired Networks ◽

Leading Role ◽

Critical Issues ◽

Impact Of Technology ◽

The Impact

Over the last couple of years, we have been witnessing the process of convergence between wireless and wired networks, under intense technological innovation and rapid market evolution. Mobile operators are trying to maintain a leading role in the market as it evolves towards integration with the Internet. However, the development of a multitude of new services will require the growth of a whole new market for network connectivity, applications and content. In order to understand the business opportunities arising and the ensuing competitive dynamics, this chapter explores the evolution of key players’ business relationships and strategies along with a range of critical issues that will be faced by companies and regulators alike.

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On the Performance of the Current MANET Routing Protocols for VoIP, HTTP, and FTP Applications

Journal of Computer Networks and Communications ◽

10.1155/2014/154983 ◽

2014 ◽

Vol 2014 ◽

pp. 1-16 ◽

Cited By ~ 13

Author(s):

Waheb A. Jabbar ◽

Mahamod Ismail ◽

Rosdiadee Nordin

Keyword(s):

Routing Protocols ◽

Performance Metrics ◽

Smart Cities ◽

Network Connectivity ◽

Simulation Models ◽

Smart Devices ◽

Mobile Environment ◽

Multihop Wireless ◽

Manet Routing ◽

The Impact

The recent advances of ensemble mobile environment of smart devices with embedded sensors have enabled the MANET to play a key role in the smart cities as well as WSN and WMN. However, these smart devices are still limited in terms of energy, processor, and memory. Moreover, the efficient routing for reliable network connectivity at anytime, anywhere, and about everything is still a challenge in multihop wireless networks. This paper evaluates the QoS and energy efficiency of three active routing protocols: (i) OLSRv2, a successor to OLSR, (ii) DYMO, a successor to both DSR and AODV, and (iii) MP-OLSR multipath extension to OLSRv2. In contrast to the related previous works which focused only on CBR traffic without considering the influence of specific traffic types on the performance of routing protocols, this work focused on this area from a different perspective. It evaluates the performance of three internet-based traffic types that can be used in the smart city applications: VoIP, HTTP, and FTP using different simulation models. The impact of the network density, load traffic, and nodes mobility on the considered protocols was evaluated by considering particular performance metrics for each traffic application. Based on the results, the study concludes by presenting useful recommendations for future work.

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Dynamics of brain connectivity after stroke

Reviews in the Neurosciences ◽

10.1515/revneuro-2018-0082 ◽

2019 ◽

Vol 30 (6) ◽

pp. 605-623 ◽

Cited By ~ 5

Author(s):

Adela Desowska ◽

Duncan L. Turner

Keyword(s):

Brain Connectivity ◽

Effective Connectivity ◽

Network Connectivity ◽

Connectivity Pattern ◽

Compensatory Mechanisms ◽

Neural Structure ◽

Motor Network ◽

The Central Nervous System ◽

Dynamic Time ◽

The Impact

Abstract Recovery from a stroke is a dynamic time-dependent process, in which the central nervous system reorganises to accommodate for the impact of the injury. The purpose of this paper is to review recent longitudinal studies of changes in brain connectivity after stroke. A systematic review of research papers reporting functional or effective connectivity at two or more time points in stroke patients was conducted. Stroke leads to an early reduction of connectivity in the motor network. With recovery time, the connectivity increases and can reach the same levels as in healthy participants. The increase in connectivity is correlated with functional motor gains. A new, more randomised pattern of connectivity may then emerge in the longer term. In some instances, a pattern of increased connectivity even higher than in healthy controls can be observed, and is related either to a specific time point or to a specific neural structure. Rehabilitation interventions can help improve connectivity between specific regions. Moreover, motor network connectivity undergoes reorganisation during recovery from a stroke and can be related to behavioural recovery. A detailed analysis of changes in connectivity pattern may enable a better understanding of adaptation to a stroke and how compensatory mechanisms in the brain may be supported by rehabilitation.

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Drone Security

Design Innovation and Network Architecture for the Future Internet - Advances in Web Technologies and Engineering ◽

10.4018/978-1-7998-7646-5.ch013 ◽

2021 ◽

pp. 352-384

Author(s):

Marc Lacoste ◽

David Armand ◽

Fanny Parzysz ◽

Loïc Ferreira ◽

Ghada Arfaoui ◽

...

Keyword(s):

Supply Chain ◽

Network Connectivity ◽

Time Constraints ◽

Security Market ◽

Technical Design ◽

Market Growth ◽

Resource Limitations ◽

Trade Offs ◽

Security Challenges ◽

The Impact

This chapter explores the security challenges of the drone ecosystem. Drones raise significant security and safety concerns, both design-time and run-time (e.g., supply-chain, technical design, standardization). Two broad classes of threats are considered, on drones and using drones (e.g., to attack critical infrastructures or vehicles). They involve both professional and non-professional drones and lead to various types of attacks (e.g., IoT-type vulnerabilities, GPS spoofing, spying, kinetic attacks). Trade-offs involving hardware and software solutions to meet efficiency, resource limitations, and real-time constraints are notably hard to find. So far, protection solutions remain elementary compared to the impact of attacks. Advances in technologies, new use cases (e.g., enhancing network connectivity), and a regulatory framework to overcome existing barriers are decisive factors for sustainable drone security market growth.

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Exploring the Impact of Dockless Bikeshare on Docked Bikeshare—A Case Study in London

Sustainability ◽

10.3390/su12156110 ◽

2020 ◽

Vol 12 (15) ◽

pp. 6110

Author(s):

Dongdong Feng ◽

Lin Cheng ◽

Mingyang Du

Keyword(s):

Network Analysis ◽

Complex Network ◽

Interaction Strength ◽

Network Connectivity ◽

Temporal Analysis ◽

Complex Network Analysis ◽

Last Mile ◽

Considerable Impact ◽

The Impact ◽

Spatial Temporal Analysis

As a green and sustainable travel mode, the bikeshare plays an important role in solving the “last-mile” problem. The new dockless bikeshare system (DBS) is widely favored by travelers, and the traditional docked bikeshare system (BS) is affected to a certain extent, but the specific circumstances of this impact are not yet known. To fill the knowledge gap, the objective of this study is to measure the impacts of DBS on London cycle hire, which is a type of BS. In this study, the travel data of 707 docking stations in two periods, i.e., March 2018 and March 2017, are included. A spatial-temporal analysis is first conducted to investigate the mobility pattern changes. A complex network analysis is then developed to explore the impact of DBS on network connectivity. The results suggest a significant decrease of 64% in the average trip amounts, with both origins and destinations in the affected area, and the trips with short and medium duration and short and medium distances are mainly replaced by DBS. DBS also has a considerable impact on the structure and properties of the mobility network. The connectivity and interaction strength between stations decrease after DBS appears. We also concluded that the observed changes are heterogeneously distributed in space, especially on weekends. The applied spatial-temporal analysis and complex network analysis provide a better understanding of the relationships between DBS and BS.

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Network Connectivity and Labor Systems

10.5406/illinois/9780252038761.003.0001 ◽

2017 ◽

Author(s):

Dan Schiller

Keyword(s):

Production Systems ◽

Network Connectivity ◽

Information And Communications Technology ◽

Labor Process ◽

Commodity Chains ◽

Capitalist Development ◽

Great Transformation ◽

Vantage Points ◽

Military Activity ◽

The Impact

This chapter discusses the impact of network connectivity on labor systems, arguing that the response to the recession of the 1970s was a profound one and eventually led to the crash of 2008. It explains how the early to mid-1970s brought forward information and communications technology (ICT) as the heart of capitalist development and situates this shift into networks within trends in production, finance, and U.S. military activity. It also examines what Kim Moody calls the “great transformation,” when a basement-to-attic redesign touched everything from the content of specific jobs to the technical division of labor within companies and entire industries, to the location of discrete and now increasingly isolable production systems. This “Great Transformation” is analyzed from two vantage points. The first concerns the labor process, the second, the wider commodity chains within which labor has been mobilized.

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The Impact of Online Learning on International Students' Studies Amid the Covid-19 Pandemic During the 2020 Spring Semester: A Case Study of Southwest University.

Asian Journal of Education and e-Learning ◽

10.24203/ajeel.v9i1.6508 ◽

2021 ◽

Vol 9 (1) ◽

Author(s):

Allan Muganga ◽

Naomy Kalabwa Leah ◽

Tebatso Namanyane ◽

Mirajur Rhaman Shaoan

Keyword(s):

Online Learning ◽

International Students ◽

Online Courses ◽

Research Question ◽

Network Connectivity ◽

Structured Interviews ◽

Spring Semester ◽

Limited Class ◽

The Impact

Toward the end of 2019 and since the beginning of 2020, there has been a worldwide collapse of the pandemic disease called covid-19 that caused a complete shutdown in several countries. As a result, schools, universities and other institutions of higher learning were forced to close. The only way learning could take place was through online learning. Unplanned online learning brought uncertainty among institutions, educators and learners which needs to be examined. The purpose of this case study was, therefore, to explore how online learning during the COVID-19 period influenced SWU international students’ studies, and to understand the attitude of these international students toward online learning during the covid-19 period and finally finding out strategies that SWU international students used to tackle the challenges they encountered through online learning. Semi-structured interviews were conducted among twelve international students offering different online courses. Researchers used content analysis to help them arrive at findings and conclusions. Results from the research showed that poor network connectivity, limited class participation was among the strongest themes to address the first research question. Passion for learning and apathy of online learning were among the themes under students’ attitude. Strategies used to cope up with the challenges faced included prior class preparations and seeking better internet connectivity showed up.

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