Node Cooperation to Avoid Early Congestion Detection Based on Cross-Layer for Wireless Ad Hoc Networks

The resent application of wireless ad hoc networks (WANET) demands a high and reliable data load. The simultaneous transfer of large amounts of data different nearby sources to nearby destinations in a massive network under these circumstances results in the possibility of network congestion. Congestion is an extremely unwanted condition because it creates extra overhead to the already deeply loaded environment, which ultimately leads to resource exhaustion, and can lead to packet drops and retransmission at either the MAC or upper layers. We present a lightweight congestion control and early avoidance congestion control scheme, which can effective control congestion while keeping overhead to a minimum. This scheme is based on the Cross-layer between the MAC and network layers lead to early detection of congestion. With the help of node cooperation the sender node is triggered to find an alternative route based on TMT. This mechanism controls the network resources rather than the data traffic. Detailed performance results show enhancement in the throughput and packet delivery ratio, as well as a reduction in packet drop. Generally, network performance increases

Maximising system throughput in wireless powered sub-6 GHz and millimetre-wave 5G heterogeneous networks

Millimetre wave (mm-Wave) bands and sub-6 GHz are key technologies in solving the spectrum critical situation in the fifth generation (5G) wireless networks in achieving high throughput with low transmission power. This paper studies the performance of dense small cells that involve a millimetre wave (mm-Wave) band and sub-6 GHz that operate in high frequency to support massive multiple-input-multiple-output systems (MIMO). In this paper, we analyse the propagation path loss and wireless powered transfer for a 5G wireless cellular system from both macro cells and femtocells in the sub-6 GHz (µWave) and mm-Wave tiers. This paper also analyses the tier heterogeneous in downlink for both mm-Wave and sub-6 GHz. It further proposes a novel distributed power to mitigate the inter-beam interference directors and achieve high throughput under game theory-based power constraints across the sub-6 GHz and mm-Wave interfaces. From the simulation results, the proposed distributed powers in femtocell suppresses inter-beam interference by minimising path loss to active users (UEs) and provides substantial power saving by controlling the distributed power algorithm to achieve high throughput

Aneurysmal Subarachnoid Haemorrhage (aSAH) and Hydrocephalus: Fact and Figures

Hydrocephalus (HCP) occurs due to the injurious effect of subarachnoid haemorrhage (SAH). It causes increased morbidity and mortality. It can be acute and frequently occurs within 48 hours and up to 7 days. Subacute hydrocephalus may occur up to 14 days and is chronic if remained or develops after 2 weeks of the subarachnoid haemorrhage. Acute hydrocephalus after aneurysmal subarachnoid (aSAH) bleeding is non-communicating or obstructive and occurs due to physical obstruction by a clot, the effect of blood in the subarachnoid space, and inflammation. Chronic hydrocephalus is due to fibrosis and adhesion, which hampers cerebrospinal fluid (CSF) absorption and increased secretion of CSF from gliosis. Various risk factors for developing hydrocephalus in aneurysmal subarachnoid haemorrhage patients range from female gender to high severity scores. Acute hydrocephalus frequently requires diversion drainage of CSF by external ventricular drain (EVD); it usually subsides within a week, and EVD is removed. Fewer patients will develop or continue to have hydrocephalus, requiring either short or longer shunting of the CSF namely by ventriculoperitoneal shunt or other modes of CSF drainage

An analytical framework for distributed and centralized mobility management protocols

Proxy Mobile IPv6 (PMIPv6) maintains the mobility management of mobile users without involving them in the signaling of mobility process. The main limitations of PMIPv6 are the high latency and packet loss. Consequently, IETF has addressed these limitations by standardizing Fast Handover for Proxy Mobile IPv6 (PFMIPv6) protocols. The whole processes of PMIPv6 and PFMIPv6 protocols, including mobility management and connectivity needs, are based on a centralized and static mobility anchor. Therefore, the centralized anchor usually suffers from enormous burdens and hence degradation in performance, scalability, and reliability of the network. Lately, Distributed Mobility Management (DMM) solution is introduced based on PMPv6 to tackle the issue of relying on a single entity. Analyzing and investigating the performance of these centralized and distributed solutions depends on traffic characteristics and user mobility model. Accordingly, we propose through these two factors an analytical framework to evaluate the handover performance of PMIPv6, PFMIPv6 and DMM in vehicular environment. Our analysis and experimental validation are very significant to determine the impacts of different network parameters on the handover performance of these protocols to facilitate decision making on which analytical framework must be adopted in a network. Analytical results demonstrate that there is a trade-off between network parameters and handover performance metrics. PFMIPv6 is the most suited protocol for low to high mobility scenarios in term of handover performance

Associated Information and Communication Technologies Challenges of Smart City Development

Smart cities development relies on information and communication technologies (ICTs) to improve all urban aspects, including governance, economy, mobility, and environment. The development is usually associated with several challenges and negative effects. This study relies on revealing ICTs challenges by firstly conducting a comprehensive literature review to identify the challenges that are most associated with ICTs. Then, a questionnaire survey was distributed among the Saudi population to study their expectations, perceptions, and concerns on the smart city concept and services. The questionnaire also investigated ICTs challenges identified from the literature review, including information security risks, privacy violation, incompatibility, and digital skill gaps. Consequently, semi-structured interviews were conducted to perceive the reasons for the incompatibility between different systems and digital skill gaps between the public. The findings show that the most likely challenges are information security risks and privacy violations, which are due to the increase in vulnerability, potential attacks, and lack of public awareness regarding personal data protection. The incompatibility between different systems and services in smart cities arouses worries among the public due to the expected high cost and difficulty of adaptation and utilization. Moreover, digital skill gaps arises between members of the population that have a low education level or are elderly persons

Associated Information and Communication Technologies Challenges of Smart City Development

Smart cities development relies on information and communication technologies (ICTs) to improve all urban aspects, including governance, economy, mobility, and environment. The development is usually associated with several challenges and negative effects. This study relies on revealing ICTs challenges by firstly conducting a comprehensive literature review to identify the challenges that are most associated with ICTs. Then, a questionnaire survey was distributed among the Saudi population to study their expectations, perceptions, and concerns on the smart city concept and services. The questionnaire also investigated ICTs challenges identified from the literature review, including information security risks, privacy violation, incompatibility, and digital skill gaps. Consequently, semi-structured interviews were conducted to perceive the reasons for the incompatibility between different systems and digital skill gaps between the public. The findings show that the most likely challenges are information security risks and privacy violations, which are due to the increase in vulnerability, potential attacks, and lack of public awareness regarding personal data protection. The incompatibility between different systems and services in smart cities arouses worries among the public due to the expected high cost and difficulty of adaptation and utilization. Moreover, digital skill gaps arises between members of the population that have a low education level or are elderly persons

An evaluation of IEEE 802.11 mac layer handoff process in CAPWAP centralized WLAN

The growing demand to provide secure wireless connectivity, especially in hot spot areas such as conference halls and events, motivated the development of Control and Provisioning of Wireless Access Point (CAPWAP) centralized Wireless Local Area Network (WLAN). The centralized WLAN utilizes an Access Controller (AC) to simplify configuration, management, and control of Wireless Termination Points (WTPs) in large scale deployment of a wireless network. In order for the clients to associate and reassociate to WTPs, scanning and authentication phases are performed. The contributed latency during scanning and authentication phases, in the MAC layer handoff process, makes it difficult to support realtime applications that are sensitive to network latencies. This work simulates the effect of using different scanning and authentication methods in CAPWAP centralized WLAN during MAC layer handoff process. This can be considered as a significant contribution since no prior work has been done, to our knowledge, to simulate the handoff latency components in centralized networks. This work also studies the effect of varied propagation environments including isolation, and indoor and outdoor environments on handoff process. Moreover, the effects of employed WTP type and the client movement speed on the handoff process latency have been analyzed. Keywords: Handoff, CAPWAP, Scanning, Authentication, Centralized Network

Studying the Relationship between the Traffic Flow Structure, the Traffic Capacity of Intersections, and Vehicle-Related Emissions

This paper proposes a new approach to assessing the impact of changes in the traffic flow on pollutant emissions and the traffic capacity of signal-controlled intersections. We present an intelligent vision system tailored to monitor the traffic behavior at signal-controlled intersections in urban areas. Traffic cameras are used to collect real-time vehicle traffic data. Our system provides valuable insight into the relationship between traffic flows, emissions, and intersection capacity. This study shows how changes in the traffic composition reduce the traffic capacity of intersections and increase emissions, especially those involving fine dust particles. Using the combination of fuzzy logic methods and Gaussian spline distribution functions, we demonstrate the variability of these relationships and highlight the need to further study compromises between mobility and air quality. Ultimately, our results offer promising opportunities for the development of intelligent traffic management systems aimed at balancing the demands of urban mobility while minimizing environmental impact. This study demonstrates the importance of taking into account the correlation between the change in the composition of traffic queues due to a random change in the traffic flow and its impact on emissions and the traffic capacity of intersections. This study found that the presence of various groups of vehicles and their position in the queue can reduce the traffic capacity by up to 70% and increase the growth of harmful emissions by 14 fold

An Accident Detection and Classification System Using Internet of Things and Machine Learning towards Smart City

Daily traffic accidents increase annually, causing a significant number of death and disability cases. Most of fatalities occur because of the late response to these emergency cases. The time after the traumatic injury is called the golden hour, where providing essential medical and surgical aid at that time increases the probability of saving human lives by one-third an average. Thus, the focus of this paper was to develop a system based on IoT for accident detection and classification. The system detects and classifies vehicle accidents based on severity level and reports the essential information about the accident to emergency services providers. The system consists of a microcontroller, GPS, and a group of sensors to determine different physical parameters related to vehicle motion. In addition, different types of machine learning classifiers were examined with the developed system to determine the most accurate classifier for the system. The classifiers are the Gaussian Mixture Model (GMM), Naive-Bayes Tree (NB), Decision Tree (DT), and Classification and Regression Trees (CART). The implementation of the system showed that GMM and CART models were better in terms of precision and recall. It was also shown that the severity of accidents depends mainly on the g-force value and fire occurrence