Reliable Connection Research Articles

Characterizing the spatiotemporal features of functional connectivity across the white matter and gray matter during the naturalistic condition.

The naturalistic stimuli due to its ease of operability has attracted many researchers in recent years. However, the influence of the naturalistic stimuli for whole-brain functions compared with the resting state is still unclear. In this study, we clustered gray matter (GM) and white matter (WM) masks both at the ROI- and network-levels. Functional connectivity (FC) and inter-subject functional connectivity (ISFC) were calculated in GM, WM, and between GM and WM under the movie-watching and the resting-state conditions. Furthermore, intra-class correlation coefficients (ICC) of FC and ISFC were estimated on different runs of fMRI data to denote the reliability of them during the two conditions. In addition, static and dynamic connectivity indices were calculated with Pearson correlation coefficient to demonstrate the associations between the movie-watching and the resting-state. As the results, we found that the movie-watching significantly affected FC in whole-brain compared with the resting-state, but ISFC did not show significant connectivity induced by the naturalistic condition. ICC of FC and ISFC was generally higher during movie-watching compared with the resting-state, demonstrating that naturalistic stimuli could promote the reliability of connectivity. The associations between static and dynamic ISFC were weakly negative correlations in the naturalistic stimuli while there is no correlation between them under resting-state condition. Our findings confirmed that compared to resting-state condition, the connectivity indices under the naturalistic stimuli were more reliable and stable to investigate the normal functional activities of the human brain, and might promote the applications of FC in the cerebral dysfunction in various mental disorders.

Towards a reliable nanohardness-dose correlation of ion-irradiated materials from nanoindentation tests: A case study in proton-irradiated vanadium

Nanoindentation has been commonly used for evaluating the hardening effects of ion-irradiated materials. Nonetheless, establishing a reliable correlation between the hardness and irradiation dose is never trivial, due to not only the intrinsic analytical challenges of this technique, such as size effects, pile-up effects, etc., but also the fact that the irradiation dose is usually uneven inside the stress volume under the indenter, especially near the depth of dose peak. In the present work, the hardening in pure V irradiated with 1 MeV proton at various fluences is investigated by using nanoindentation tests, combined with the characterization of both irradiation defects and dislocations of the indented material. Under the cross-sectional indentation, we demonstrate that the nanohardness-dose correlation can be unified from the samples irradiated to different fluences and at different depths on each sample, as long as the lateral spanning of indenter is carefully considered. Crystal-plasticity finite-element-modeling simulation results can well describe the measured hardening-dose correlation, as well as the observed features on the change in strained fields and pile-up effects after irradiations. Moreover, the measured hardness is further corrected for the dose-dependent pile-up based on the surface profiling, and the indentation size effects based on surface indentation tests for deeper indentation depth, to reach a reliable connection between the hardening effects and the irradiation dose. Furthermore, microstructural characterization of the indented materials shows the pinning of dislocation by irradiation defects and the sweeping of those defects during dislocation migration. Molecular dynamics results suggest that the drag of loops by edge dislocations might cause the annihilation or aggregation of small loops, which could be responsible for the lower density but the larger size of irradiation loops in the strained region.

LTE/LTE-A Based Advanced Wireless Networks

LTE/LTE-A is a wireless broadband standard that provides quick and reliable connectivity for the Internet of Things (IoT) and other connected devices. It is the de facto standard for 4G wireless, offering high-speed communication, extensive network coverage, and low latency. LTE/LTE-A networks are crucial for real-time IoT applications, offering high-speed data transfer, extensive coverage, low latency, and scalability. However, challenges in evaluating LTE/LTE-A-based wireless networks for IoT include compatibility, cost, power consumption, network coverage, and security. Large-scale deployments are hindered by cost, power usage, real-time data transfer, security vulnerabilities, and interoperability. Network performance may be impacted by high data traffic levels, expensive setup and maintenance, and interference from other wireless devices. LTE/LTE-A networks are complex and require sophisticated network technologies and protocols, making them difficult for some IoT stakeholders to build and administer.

Developing Electronic Portfolios to Align with Diverse National Standards to Showcase Students’ and Teachers’ Performance: A Design Approach

Traditional methods of documenting and assessing educational performance and achievements have often been limited in scope and accessibility. Addressing these limitations is to leverage the potential of technology to create a comprehensive and user-friendly electronic portfolio (e-portfolio) system. This study aimed to investigate the required national standard and functionalities of e-portfolios for showcasing students’ and teachers’ performance. This study adopted qualitative research methods to investigate the context under study. Interviews, documents, and reports with and from students, lecturers, administrators, and educational experts provided insights into the specific requirements and expectations for an effective electronic portfolio system. One hundred twenty-five participants were randomly sampled for the study in the Abuja metropolis of Nigeria. Data were collected using a semi-structured interview and case study approach. A deductive approach was employed for the coding and analysis of the transcribed data. The findings identified several key features and functionalities required in an electronic portfolio system: Customizability and Flexibility, Alignment with Standards, Multimedia Capabilities, Reflection, and Goal-Setting Tools. Both students and teachers generally perceived the use of electronic portfolios positively. The respondents highlighted technological barriers, such as lack of necessary skills, limited access to devices or reliable internet connectivity; time constraints; and resistance to change as challenges in using e-portfolios to showcase their performance. Based on a systematic analysis of interview data from the respondents, the qualitative study offers a framework for exploring, understanding, and discussing the standard for and the impact of developing electronic portfolios for student and teacher performance.

The perceptions of lecturers about blended learning at a particular higher institution in South Africa

The purpose of this research is to analyse the support that lecturers need to be able to implement a blended learning approach successfully. Blended learning is now seen as an approach that can create engaging learning environments, to enhance students’ self-directed learning and improve the whole learning experience. The study investigated the perceptions of thirteen lecturers, at a particular higher education institution, regarding the advantages and challenges of blended learning in South Africa. A qualitative research design was chosen for this study because it enabled the authors to explore the theme in detail. Semi-structured open-ended interviews were conducted to collect the necessary data from the lecturers, who were chosen through the use of homogenous purposeful sampling. The data collected were coded, using the induction method. This helped to reveal relevant codes, which were categorised. A literature review was conducted, in which recent research on this topic was analysed and used to correlate the findings of the field research of this study. This study reports on the actual views and experiences of the participants. The research findings and relevance for teaching in higher education institutions are discussed. The conclusion is that, for such an approach to be successful, lecturers would require support from management, more training, improved professional development, as well as reliable technology and internet connections. In addition, lecturers would require additional time to implement such an approach.

An Analysis of Literature on the Growth of E-Commerce in India

Abstract: If the Indian economy's fastest-growing sectors is e-commerce. Despite having a rapid development rate, India's ecommerce sector has lagged behind that of many established and rising nations, largely because of the country's small population of internet users. According to a 2015 research by the international management consulting firm AT Kearney, only 39 million Indians purchased goods online, which represents a very small portion of the 1.2 billion people who call India home. However, the spread of technology as well as the use of the internet and mobile devices create a favorable environment for the growth of e-commerce in India. A digital revolution is about to begin throughout the nation. the introduction of 4G services and a decrease in the cost of data plans, data cards, and USBThe cost of owning a reliable internet connection has decreased thanks to dongles.

Experimental Study on the Mechanical Properties of Vertical Corrugated Pipe Grout Anchor Connection Joints

Prefabricated buildings’ quality, safety, and construction efficiency are closely related to the connections between various prefabricated components. This study optimizes the design of corrugated pipe-restrained grout anchor lap connections, further simplifying the construction methodology while ensuring reliable connection performance. The objective is to achieve cost savings and accelerate construction progress. A pull-out test of this new type of joint is conducted, generating two sets of 17 specimens each. The research examines the effects of grouting material strength, grout anchor steel bar anchorage length, and U-shaped stirrup spacing on the connection performance of corrugated pipe grout anchor connections. The results indicated that the specimens primarily experience two types of failure: anchorage failure with steel bar pull-out and steel bar tensile failure without anchorage failure. The strength of the grouting material and the anchorage length of the grout anchor steel bar positively correlate with bond anchorage performance. U-shaped stirrups contribute to restraint and enhance the bonding force between the corrugated pipe, grouting materials, and the grout anchor steel bar to a certain extent.

A framework for understanding reliability in container shipping networks

Improving reliability is increasingly regarded as an important topic in maritime transportation, especially given the significant impact that both uncertainty and delays in shipping and at ports have on the efficient flow of freight along wider supply chains. The term ‘reliability’ appears in different academic fields and with a variety of different meanings and interpretations. In transportation, reliability has been studied in most modes, but less so in the case of maritime containerisation. This paper reports on a systematic literature review of the concept of reliability in transportation, with a focus on reliability in container shipping networks. The selected papers were analysed to extract information according to the three identified sub-networks: (1) ports, including studies with a focus on infrastructure, service availability and risks in ports and hinterlands; (2) network structures, including the configuration of the networks, the vulnerability and resilience of the existing networks; (3) supply chains, including connectivity and planning of activities that integrate stakeholders within the supply chain. These sub-networks were then used to further query the database, searching for papers relevant to the research problem. Two research questions are addressed: (1) How is reliability best understood in the context of container shipping networks? (2) What are the determinants that affect container shipping network reliability? The review showed that there is no uniform definition of reliability in container shipping networks, but different approaches to understand it, depending on the theoretical perspective, have been adopted. Influencing factors and relevant metrics are discussed and a framework combining different dimensions of reliability, expressed as three themes, i.e., infrastructure reliability, network configuration reliability, and connectivity reliability, is developed. This can help both practitioners and researchers to understand in more detail the various dimensions and nuances of reliability specifically in the context of container shipping, its interrelationship with wider logistics systems and how, where possible, reliability can be improved.

GAMIFICATION AND SOLO TAXONOMY: A STRATEGY TO PROMOTE ACTIVE ENGAGEMENT AND DISCIPLINE IN ENGLISH LANGUAGE LEARNING

The motivation for this study arises from the potential of gamification, particularly the integration of game-based platforms like Kahoot!, to enhance active communicative language use within the classroom. The research aims to investigate the impact of implementing gamification based on SOLO taxonomy's relational level on the Kahoot! application on active participation, discipline, and learning outcomes in the context of English language learning. This study employs a descriptive research methodology, involving observations, interviews, and assessments, with a participant group comprising 35 nursing program students. Descriptive analysis reveals that gamification within the SOLO taxonomy framework positively influences students' active engagement and discipline, although there are fluctuations in their learning outcomes. Students express enthusiasm for utilizing the Kahoot! application for English learning, but they encounter occasional connectivity issues that hinder problem-solving activities. Consequently, the integration of technology is a promising approach for enhancing English language skills, with a reliable internet connection being a critical factor for success when using the Kahoot! platform.

Techno-economic assessment of 5G infrastructure sharing business models in rural areas

How cost-efficient are potential infrastructure sharing business models for the 5G era (and beyond)? This significant question needs to be addressed if we are to deliver universal affordable broadband in line with Target 9.1 of the UN Sustainable Development Goals. Although almost two-thirds of the global population is now connected, many users still lack access to high-speed and reliable broadband connectivity. Indeed, some of the largest connectivity issues are associated with those living in areas of low economic viability. Consequently, this assessment evaluates the cost implications of different infrastructure sharing business models using a techno-economic assessment framework. The results indicate that a rural 5G neutral host network (NHN) strategy helps to reduce total cost between 10 and 50% compared with other sharing strategies. We also find that, compared to a baseline strategy with No Sharing, the net present value of rural 5G sharing strategies can earn between 30 and 90% more profit. The network upgrades to 5G using various sharing strategies are most sensitive to changes in the average revenue per user, the adoption rate, and the amount of existing site infrastructure. For example, the results from this study show that a 20% variation in demand revenue is estimated to increase the net present value of the sharing strategies by 2–5 times compared to the No Sharing strategy. Similarly, a 10% increase in existing infrastructure lowers the net present value by 8–30%. The infrastructure sharing strategies outlined in this study have the potential to enhance network viability while bridging the digital divide in remote and rural locations.

The level of C-reactive protein in patients with acute pulmonary embolism

Background. Modern risk stratification in patients with pulmonary embolism (PE) does not consider all possible factors that may influence the course and prognosis of the disease. In view of this, it is promising to study inflammatory markers, especially C-reactive protein (CRP), for their prognostic value in PE. The purpose was to study the clinical and prognostic value of increased CRP levels in patients with PE during hospitalization. Material and methods. One hundred and three patients with diagnosis of acute PE confirmed by computed tomographic pulmonary angiography (CTPA) or by autopsy were examined, their СRP level was evaluated during hospitalization. In addition to a general clinical examination, all patients were screened for PE risk factors and risk of premature death according to the ESC 2019 guidelines. La-boratory tests included quantitative determination of CPK-MB, D-dimer and СRP in addition to basic ones. Electrocardiography, echocardiography, and CTPA were performed as part of the instrumental studies. Results. Depending on the СRP median (26 mg/l), patients were divided into two groups. Group 1 (СRP < 26 mg/l) included 52 people, group 2 (СRP > 26 mg/l) — 51 patients. It was found that in group 1, patients with low risk predominated (p = 0.044) and the average pulmonary embolism severity index was significantly lower (p = 0.011). In group 2, the average blood oxygen saturation (SpO2) during hospitalization was significantly lower (p = 0.004), the average parameters of the left ventricle, namely end-diastolic and end-systolic volume, were significantly greater (p = 0.045 and p = 0.043, respectively), and the ejection fraction was significantly lower (p = 0.002). Also, the average levels of leukocytes (p = 0.0003), neutrophils (p = 0.00001), urea (p = 0.008), CPK-MB (p = 0.028) and erythrocyte sedimentation rate (p = 0.012) were significantly higher in group 2. Correlation analysis revealed a reliable inverse connection between CRP levels and initial SpO2 and a direct relationship between CRP level and the size of the right atrium, CPK-MB level, and increased risk of early mortality from PE. Conclusions. Elevated CRP was found in 92 % of patients with acute PE and was associated with a significant decrease in SpO2 (p < 0.004), increased left ventricular size (p < 0.05), and decreased ejection fraction (p < 0.003). Correlation analysis revealed a relationship between CRP level and the risk according to the pulmonary embolism severity index, SpO2, the level of CPK-MB and the size of the left atrium.

The Influence of Institutional Resources on Doctorate Degree Enrolment and Completion Rates in Selected Public Universities Kenya

Doctorates are fundamental pivot towards facilitating the social and economic transformation of a nation. Nevertheless, research on doctorate education point out that most candidates in Kenyan public universities spend lengthy period of time to earn their doctorate degrees. Furthermore, data of those enrolling in selected Kenyan public universities demonstrate that less students enroll for doctorate programmes in contrast with those who register for Master and Bachelors’ programmes. Institutional resources have been cited as a critical ingredient toward enhanced students’ enrolment into doctorate programmes. The purpose of this paper was, therefore, to establish the influence of institutional resources on doctorate degree enrolment and completion rates from selected Kenyan public universities. The study sought to analyse institutional resources influence on doctorate degree programmes enrolment and completion rates from selected public universities in Kenya for the last fifteen years. The study employed the mixed methods research design. Data was collected from four purposively sampled universities using questionnaires, analysis of documents (on enrolment, completion and staff enrolments) and interview schedules. Qualitative data was coded and then thematically analysed guided by the study objectives while quantitative data was analysed using percentages and graphs. The study revealed that institutional resources influence enrolment and completion rates at doctorate level. Availability of qualified and sufficient academic staff, funding, mentorship programmes, well equipped libraries, reliable internet connections and ambient social environment to be critical in determining where one enrolls for a doctorate programme and how long it will take to complete. The study furthermore established that between 2003 and 2017, there was low doctorate programmes enrolment and completion rates at the selected public Universities Kenya. This was demonstrated from trends in the numbers of those who enrolled and those who graduated. The trends revealed that more males than females enrolled and completed their studies with the highest being between 2008 and 2013. The findings of this research would be resourceful to university policy makers, administrators and lecturers to improve on institutional policy framework with regard to institutional resources which could be used to enhance doctorate programme enrolment and completion in Kenyan public universities.

Investigations of selected influencing process factors for transient liquid phase soldering (TLPS) as a die-attach method for automotive power modules

Increasing the operating temperatures in power electronic applications cause a decreasing lifetime of the die-attach interconnection. Transient liquid phase soldering (TLPS) is able to create a reliable and high temperature resistant connection layer via diffusion processes in the form of intermetallic phases with melting points up to > 400°C. This study concentrates on a TLPS reflow-soldering process with a tin-copper-tin (Sn-Cu-Sn) layered preform. During the soldering process the influence of the selected process parameters for the Sn-Cu-Sn on the grown intermetallic phase interconnections between the preform and the components are investigated via the average void percentage and a process capability analysis (cpK). The application of mechanical pressure decreases the average void percentage below 10%. Due to the lower average void percentage the influence of the holding time, peak temperature and heating gradient are examined under low pressure. The biggest impact shows the heating gradient. With a slow heating gradient, the thermomechanical stress decreases by increasing the solubility and the average void percentage could be reduced to less than 2.7 %. In combination of the optimized selected process factors it is possible to reach a process capability value of 1.

Internet of Things (IoT): Wireless Communications for Unmanned Aircraft System

In times of technological advancements, the use of aerial vehicles (UAVs), commonly known as drones, has become increasingly prevalent across various commercial and industrial sectors. UAVs find applications in agriculture, filmmaking, law enforcement, package delivery, aerial photography, videography, etc. There are benefits associated with utilizing UAVs. One key advantage is their ability to cover areas quickly and efficiently while accessing locations that may be challenging or hazardous for humans. Wireless communication technologies play a role in ensuring the functioning of Unmanned Aircraft Systems (UAS). Without these technologies, the United States of America would face difficulties communicating with ground control stations or relaying information to operators. This would significantly impede the country’s mission execution and overall responsibilities. Wireless communication technologies (WCT) enable the United States to maintain awareness—essential for achieving successful and secure operations. Additionally, wireless technologies allow for Unmanned Aerial Systems (UAS) control, which is crucial for missions carried out in hostile or dangerous environments. The increasing usage of drones has highlighted the need to improve networks in the United States focusing on their ability to work together effectively handle volumes of data and provide reliable broadband connectivity. This research delves into communication technologies, in this domain emphasizing their advantages, limitations, industry standards and potential areas for future investigation to address the challenges revealed by this study.

Smarter Data Transfer Through Light-Fidelity Systems

The proliferation of wireless communication technologies has spurred the exploration of novel approaches to address the increasing demand for high-speed data transmission and alleviate the challenges posed by radio frequency-based systems. Li-Fi (Light Fidelity) has emerged as a promising paradigm by harnessing visible light to establish data communication. This research paper delves into the intricate mechanics, capabilities, and potential applications of Li-Fi technology. The underlying principles of Li-Fi involve the modulation of visible light using light-emitting diodes (LEDs) to transmit data in the form of binary signals. This modulation occurs at high speeds, beyond the perceptible range of the human eye, enabling the encoding and transmission of vast amounts of data. By capitalizing on the unexplored spectrum of visible light, Li-Fi not only offers remarkable data transfer rates but also addresses concerns related to electromagnetic interference, a constraint often encountered by radio frequency-based systems. The significance of Li-Fi extends to diverse domains, including indoor wireless communication, the Internet of Things (IoT), and intelligent lighting systems. In environments where radio frequency signals encounter limitations, such as aircraft cabins and healthcare facilities, Li-Fi presents a compelling solution by providing reliable connectivity. Moreover, the integration of data communication capabilities with existing illumination infrastructure has the potential to pave the way for energy-efficient smart environments, thereby aligning with contemporary sustainability objectives.

Enhancing IoT Connectivity and Services for Worldwide Ships through Multi-Region Fog Cloud Architecture Platforms

As technologies such as eco-friendly ships, electric propulsion vessels, and multi-fuel propulsion systems advance, the scope of IoT applications in maritime fields is expanding, resulting in increased complexity in control factors. The gradual progression towards Maritime Autonomous Surface Ships (MASS) is further driving the evolution of ship-based IoT applications. These advancements underscore the necessity for a platform capable of ensuring reliable connectivity between ships and onshore. The limitations of the existing single cloud architecture become evident in this context. In response to these emerging challenges, this paper presents a cloud-based data platform structure anchored in the architecture of a multi-region fog cloud. Concurrently, we propose a strategic approach aimed at enhancing collision avoidance performance. This is achieved through the seamless sharing of navigation plan data among ships facilitated by the proposed platform structure. In regions densely populated with ships, there looms a potential for packet loss as data traffic sharing intensifies through the platform. To address this concern, we devised a traffic model based on the AIS data generation cycle and proposed an algorithm for subscription decision. Subsequently, we conducted comparative analyses of packet loss probabilities between the single cloud structure and the multi-region fog cloud structure. This was achieved through experimental packet loss data collected via the AWS cloud. Simulation results underscored a notable difference: with 100 subscribed ships, the packet loss probability in regions assuming a single cloud was about 28 times higher compared to the same region within the multi-region fog cloud structure. These simulations affirm the stable and effective implementation of the proposed collision avoidance performance enhancement method within the multi-region fog cloud structure. Furthermore, feasibility was corroborated through the successful implementation of the proposed platform via the AWS Cloud.

Surgical tele-mentoring using a robotic platform: initial experience in a military institution

BackgroundSurgical tele-mentoring leverages technology by projecting surgical expertise to improve access to care and patient outcomes. We postulate that tele-mentoring will improve surgeon satisfaction, procedural competence, the timeliness of operative intervention, surgical procedure efficiency, and key intra-operative decision-making. As a first step, we performed a pilot study utilizing a proof-of-concept tele-mentoring process during robotic-assisted surgery to determine the effects on the perceptions of all members of the surgical team.MethodsAn IRB-approved prospective feasibility study to determine the safety and efficacy of remote surgical consultation to local surgeons utilizing robotic surgery technology in the fields of general, urology, gynecology and thoracic surgery was performed. Surgical teams were provided a pre-operative face-to-face orientation. During the operation, the mentoring surgeon was located at the same institution in a separate tele-mentoring room. An evaluation was completed pre- and post-operatively by the operative team members and mentor.ResultsFifteen operative cases were enrolled including seven general surgery, four urology, one gynecology and three thoracic surgery operations. Surveys were collected from 67 paired survey respondents and 15 non-paired mentor respondents. Participation in the operation had a positive effect on participant responses regarding all questions surveyed (p < 0.05) indicating value to tele-mentoring integration. Connectivity remained uninterrupted with clear delivery of audio and visual components and no perceived latency. Participant perception of leadership/administrative support was varied.ConclusionsSurgical tele-mentoring is safe and efficacious in providing remote surgical consultation to local surgeons utilizing robotic surgery technology in a military institution. Operative teams overwhelmingly perceived this capability as beneficial with reliable audio-visual connectivity demonstrated between the main operative room and the Virtual Medical Center. Further study is needed to develop surgical tele-mentoring to improve patient care without geographic limitations during times of peace, war and pandemic outbreaks.

Enabling containerized Central Unit live migration in 5G radio access network: An experimental study

5G mobile networks have gained considerable attention and traction by offering numerous benefits such as high data rates, low latency, reliability, and application specific connectivity. To effectively achieve these milestones mobile network functions must be virtualized using Virtual Machine (VM) and/or Containers. The latter has gained momentum in recent years due to its reduced resource usage and virtualization overhead, improving efficiency and flexibility while sharing compute and network resources. While containerization offers numerous benefits, it still faces specific challenges, one of them being the ability to provide robustness and resiliency of the containerized network functions under challenging network conditions, e.g., varying load conditions and application types. The currently available open-source container platform(s) do not achieve a full-fledged containerized mobile network protocol stack as they fail to support successful live migration of containers that execute specific 5G software functionalities.The contribution of this study is to present a proof-of-concept implementation that completes the live migration of a containerized 5G Central Unit (CU) module between two servers without causing permanent service disruption to the mobile user. The authors’ implementation makes use of an open-source migration software (CRIU) that has been modified to support the protocol (SCTP) used by the CU to exchange signaling messages with other 5G modules. The authors’ implementation is experimentally tested in a federated testbed environment by applying four container migration techniques, namely Cold, Pre-Copy, Post-Copy, and Hybrid-Copy migration. A performance comparison reveals that the end-user service recovery time due to the CU live migration can be reduced by up to 36% when applying the hybrid migration technique compared to the conventional cold migration technique. Additionally, experimental results reveal that compared to state-of-the-art VM migration the container-based migration approach reduces both migration time and service downtime by 96.7% and 75.2%, respectively.

Performance analysis of a hybrid FSO/mmWave/THz system for short-range communication under rain and fog conditions

For fronthaul cellular networks, the suitability of a hybrid free space optical (FSO)/radio frequency (RF) high data rate communication systems such as millimeter wave (mmWave) and terahertz (THz) with reliable connectivity under weather conditions (rain and fog) is proposed and analyzed. The aim of this hybrid system is to suit short-range communication covering 5G/6G and beyond cellular networks. The 4 pulse amplitude modulation (PAM) scheme parallel transmission and adaptive receiver approach is considered for the work. The theoretical work on estimating the attenuation characteristics under various weather conditions is carried out followed by the simulation of a hybrid communication system for obtaining the received power at different link lengths. Based on the received power for a data rate of 1 Gbps signal-to-noise ratio (SNR) and bit error rate (BER) is calculated for a link length of 0.2 km, 0.5 km, and 1 km for 4 PAM. For varying fog conditions, mmWave/THz carrier is found to be suitable with a BER of 10−10 at a link length of 0.5 km. For varying rain rates, FSO performs well with a BER of 10−8. The link length and performance can be improved with increased transmit power in both communication systems. The THz carrier offers a high data rate, and a hybrid system is proposed with FSO/THz to have reliable connectivity in harsh weather scenarios.

A - 4 Establishing Test-Retest Reliability of Large-Scale Neural Networks after Neurotrauma: toward Clinically Useful Biomarkers.

Integrating neuropsychological assessment and resting-state functional magnetic resonance imaging (rsfMRI) may provide crucial information about brain functioning and cognition. However, rsfMRI is not ready to be used clinically due to questions about reproducibility. This study investigated the test-retest reliability of resting-state networks in moderate-to-severe TBI using back-to-back rsfMRI scans. 51 TBI participants and 28 healthy controls received two, 10-minute rsfMRI scans separated by minutes. The data were preprocessed with fMRIPrep. XcpEngine was used to divide the brain into 264 regions based on the Power atlas, which were then grouped into 13 brain networks. Intraclass correlation coefficients (ICCs) were calculated to examine the reliability of within-network connectivity (strength of a region's connection to other regions within the same network) for each network across each participant's two scans. ICCs for healthy controls varied in reliability (ICCs = 0.42-0.80). ICCs for the TBI group varied similarly (ICCs = 0.41-0.86). For both groups, the most reliable networks were the dorsal attention, visual, and sensory networks (ICCs = 0.77-0.81). The least reliable networks were the cerebellar and ventral attention networks (ICCs = 0.42-0.43). Overlapping intervals for the ICC values indicated non-significant differences in network reliability between the healthy control and TBI groups. Results suggest that within-network connectivity is more reliable in attentional and sensory networks, even after significant neurological compromise. However, the variability of within-network ICCs should continue to be explored. Alterations in network reliability may relate to changes in cognition and serve as a starting point to identify resting-state biomarkers, especially after moderate-to-severe TBI.