Transmission Failure Research Articles

Smart Energy Control Internet of Things based Agriculture Clustered Scheme for Smart Farming

The era of smart farming has already begun, and its consequences for society and environment are expected to be massive. In this situation, Internet of Things (IoT) technologies have become a key route towards new agricultural practices. IoT nodes detect and track physical or environmental conditions and transmit data through multihop routing to their base station. However, these IoT nodes have come up with energy constraints and complex routing processes due to limited capacities. Hence, lead to data transmission failure and delay in the fields of IoT-based farming. Because of these limitations, the IoT nodes distant from the base station are dependent on their cluster heads (CHs), causing additional load on CHs leading to high energy consumption and shortening their lifetime. To address these issues, this research proposes a smart energy control IoT based agriculture clustered scheme to reduce load on CHs by introducing a novel clustering scheme. Simulations are conducted for validation and comparison is made with LEACH protocol in Agriculture and results show that proposed scheme has much lower energy consumption and longer network life as compared to its counterparts.

Guaranteed time slot trade-off in QOS improvement with IEEE standard 802.15.4 for wireless sensor networks at the MAC layer

Abstract The performance of wireless sensor networks (WSNs) with IEEE standard 802.15.4 at different types of devices can be improved with the appropriate utilization of guaranteed time slots (GTSs) in superframe at the media access control (MAC) layer. GTS implementation at the MAC layer enhances quality of service (QoS) by providing guarantee for delivery in time to the data collected at real time by the reduced functional device (RFD) from the surroundings to be transmitted to the fully functional device (FFD). Results prove that trade-off has to be done in implementing GTSs for various network performance parameters like queue size, queuing delay, CSMA medium access delay, CSMA transmission failures, and network output load to improve QoS.

Research on Resource Efficiency Optimization Model of TDMA-Based Distributed Wireless Ad Hoc Networks

Because of networking flexibility, strong robustness and expansibility, and low cost of operation and maintenance, distributed wireless ad hoc networks are widely used in ultra-density 5th-Generation (5G) networks, Device to Device (D2D) communications and industrial wireless sensor networks. However, compared with the centralized ones, the Time Division Multiple Access(TDMA)-based distributed network lacks centralized coordination by a control center, while its resource scheduling only depends on partial information, and the high receiving failure probability caused by neighbors’ cumulative interference outside the scope of maintenance may reduce the resource efficiency and restrict its usability according to the existing protocols severely. The simulation results show that the transmission failure probability can be up to 20% when maintaining two-hops neighbors in TDMA-based coordinated distributed scheduling. But the research on the cumulative interference outside the scope of maintenance and the optimal neighbor maintenance scope is still unclear at present. In this paper, we establish a resource efficiency model and an interference model of control messages and data messages under different neighbor maintenance by hardcore point process (HCPP) considering cumulative interference, cost of Media Access Control (MAC) layer and channel multiplex. Furtherly, we build an optimization model to maximize the resource efficiency under scheduling delay and receiving success probability constraints, thus we can obtain the optimal scope of maintenance in different network conditions. We conduct extensive theoretical analysis and simulations to evaluate the correctness of models. Simulation results show that the resource efficiency optimization model can provide guidance for optimal protocol parameters design.

Uplink Channel Access Enhancement for Cellular Communication in Unlicensed Spectrum

3GPP cellular communications in unlicensed spectrum allow transmission only after completing listen-before-talk (LBT) operation. For downlink, the LBT operation helps cellular traffic to coexist well with Wi-Fi traffic. However, cellular uplink transmission is attempted only at the time specifically determined by the base station after having a successful LBT and the user equipment (UE) may suffer transmission failure and delayed transmission due to Wi-Fi interference. As a result, cellular uplink traffic does not coexist well with Wi-Fi traffic. This article mathematically analyzes the problem of unfairness between cellular and Wi-Fi for uplink channel access. To address the coexistence problem in unlicensed spectrum, we propose a standard-compliant approach, termed UpChance, which allows the UE to use a minimum length of uplink reservation signal and the base station to determine the optimal timing for the UE’s uplink transmission. Through ns-3 simulation, we verify that UpChance improves the performance of fairness and random access completion time by up to 88% and 99%, respectively.

Nerve conduction study as a diagnostic tool in atypical presentation of accidental organophosphorus poisoning

Poisoning with organophosphorus (OP) compounds is a worldwide phenomenon. However, atypical presentation of OP toxicity, particularly when there is a paucity of muscarinic manifestations, can be a diagnostic challenge. We report a patient with atypical symptoms where exposure to OP poison was not clearly determined. Motor nerve conduction studies done to rule out acute motor neuropathy revealed that a single supramaximal stimulus-evoked repetitive compound motor action potentials. As this finding is the earliest and most sensitive indicator of acetylcholine esterase inhibition, OP poisoning was suspected. Decreased plasma acetylcholinesterase levels confirmed the diagnosis. The patient recovered completely with treatment. Although the diagnostic hallmark of OP poisoning is a reduction in serum and red blood cell cholinesterase activity, clinicians should be alert to recognize evidence of neuromuscular transmission failure seen on nerve conduction study to diagnose atypical or concealed cases of OP poisoning.

Review on solar disturbance studies and electric power transmission line fault in Malaysia

<span lang="EN-GB">This work is a review on previous research and studies on the solar disturbance activities and faults that occur on the electric power transmission line. Research has shown that low latitude regions could also be affected by solar disturbance events. The effects of these events on earth are considerable and may cause electric power transmission failure. Geomagnetically induced current is one of the ground impacts to the transmission line, which may cause fault or disturbance and consequently power system failure. Solar disturbance data from magnetometers and electric power transmission line fault data from a digital fault recorder are reviewed in this work. These data would be valuable in determining the characteristics and effects of solar disturbances on Malaysia’s electric power transmission lines.</span>

Numerical Simulation of Gear Heat Distribution in Meshing Process Based on Thermal-structural Coupling

The thermal balance state of high-speed and heavy-load gear transmission system has an important influence on the performance and failure of gear transmission and the design of gear lubrication system. Excessive surface temperature of gear teeth is the main cause of gluing failure of gear contact surface. To investigate the gear heat distribution in meshing process and discuss the effect of thermal conduction on heat distribution,a finite element model of spur gear is presented in the paper which can represent general involute spur gears. And a simulation approach is use to calculate gear heat distribution in meshing process. By comparing with theoretical calculation, the correctness of the simulation method is verified, and the heat distribution of spur gear under the condition of heat conduction is further analyzed. The difference between the calculation results with heat conduction and without heat conduction is compared. The research has certain reference significance for dry gear hobbing and the same type of thermal-structural coupling analysis.

Reliability Analysis of Molecular Communication Based on Drift Diffusion in Different Topologies

Molecular communication is a novel nanoscale communication method. It can use ions, biochemical molecules or other information carriers to transmit information. However, due to molecules are easily accumulated in the channel to produce strong internal symbol interference, the information transmission in the channel is vulnerable to a low reliability. Therefore, reliability has become an important research issue in the field of molecular communication. At present, the existing reliability model of molecular communication does not take into account the drift velocity of the medium. Nevertheless, in some scenarios, it is often necessary to consider the effect of the drift velocity of the medium on the reliability of molecular communication. In this paper, we introduce the drift velocity of the medium and propose a reliability model of molecular communication based on drift diffusion (MCD2) in different topologies. Furthermore, in the case of transmission failure, a retransmission mechanism is used to ensure reliable transmission of information. Finally, we also compare the reliability performance of molecular communication between reliability model of MCD2 and reliability model of molecular communication based on free diffusion. The simulation results indicate that the proposed reliability model is superior to the existing reliability model of molecular communication based on free diffusion in analyzing the reliability of MCD2.

Distributed and Localized Hub-Based Hierarchical Information Transmission Control in Large-Scale Wireless Cloud Networks

This paper proposes a virtual infrastructure-based hierarchical information transmission scheme consisting of two phases, macroscopic transmission and local transmission controls. The macroscopic transmission control builds a hub-node-based virtual infrastructure and then finds the optimal hub route that satisfies the stochastic end-to-end delay constraint. Each node determines whether it belongs to a hub node by itself in a distributed manner. The local transmission control builds a robust local path between hub nodes by using the synchronized redundancy concept; this minimizes the effects of transmission failure by reducing the control traffic overhead and time to reconfigure transmission paths without rediscovery of the transmission path from the source node. Simulations confirmed that, as the network size increased, the performance of the proposed transmission scheme increased in terms of packet delivery ratio and control packet overhead. The scheme can be applied to mobile ad hoc cloud computing systems based on self-organizing vehicular networks or drone networks as a key control.

Evidence for Use of Tenofovir in Pregnancy to Prevent Perinatal Transmission of Hepatitis B Infection.

Perinatal transmission of hepatitis B virus continues to be a serious global public health concern. Transmission failures are related to high maternal viremia. Several antiviral therapies reduce maternal viremia around the time of delivery and decrease maternal-to-child-transmission. This chapter is a review of current studies that, ultimately, have provided strong evidence for the efficacy and safety of 3 antiviral drugs in pregnancy-lamivudine, telbivudine and tenofovir. The latter drug is the particular focus of this chapter which will show that tenofovir is the preferred antiviral therapy in pregnant women because of its potency, safety profile, and low risk of resistance.

Grid Based Clustering with Intrusion Detection System to Extend Network Lifetime in Mobile ADHOC Network

The key determination of researches on cluster-based Mobile Ad-hoc Networks (MANETs) and the election of consistent energy holding Cluster Head (CH) is to improve the lifetime of the network. Both in real-time as well as non-real-time basis data are collected and spread accordingly. Energy efficiency is said to be the major concern in MANET. Every node in the network supplied with preferred node energy and it will get exhausted whenever node transmits the data. When node runs out of energy transmission may be failed. In order to avoid transmission failure, energy-efficient methods are incorporated in data transmission. In this paper, a clustering method is proposed which is grounded by the Grid-based model. Static sinks in the MANET transmit the data to the transmission area which is distant to the destination that may lead to the energy-hole problem. Hence, an efficient approach is proposed wherein a centralized cluster configuration by the mobile sink is used for Grid-Based Clustering (GBC) and Verification algorithm to achieve improved energy balance to thereby extending network lifetime in the network. The simulation results depict that the GBC and Verification method can effectively increase the network lifetime and energy dissipation.

Optimal resource utilisation algorithm for visible light communication‐based vehicular ad‐hoc networks

With the advent of visible light communication (VLC) and vehicular ad-hoc networks (VANETs), the realisation of the intelligent transportation system (ITS) is becoming a reality. In high-mobility networks such as VANETs packet transmission failure may occur frequently if network lifetime, connectivity, and load balancing are not considered during next-hop link selection. Optimal resource utilisation can address the network lifetime, network connectivity, and network load balancing problems in ITS. This study investigates the problem of optimal resource allocation for VLC-based VANETs. The authors present a multi-objective integer linear programming (ILP) model that optimises resource utilisation in VLC-based VANETs, wherein the objectives are maximising network lifetime, load balancing, and network connectivity. Illustrative numerical results demonstrate that their solution achieves promising results, however, for high vehicle density, the problem is intractable. Therefore, they proposed a heuristic algorithm that addresses the problem when vehicle density is high in a network. They demonstrate the benefits of the proposed algorithm by comparing their solution against optimal resource utilisation unaware strategy, wherein resources are assigned randomly without considering resource optimisation. Their experimental study shows that both the ILP model and the heuristic algorithm increase network performance in terms of maximising network lifetime, connectivity, and load balancing.

Neuromuscular junction transmission failure is a late phenotype in aging mice

Neurodegeneration has increasingly been considered an important factor in the pathogenesis of sarcopenia or age-related loss of muscle mass and strength. Experiments were designed to investigate the fidelity of neuromuscular junction (NMJ) transmission across the lifespan in hindlimb muscles of male and female C57BL/6J mice (at 12, 20, 24, 27, and 29 months of age). Single-fiber electromyography recordings demonstrated abrupt onset of NMJ transmission failure at 27 months of age. Failed NMJ transmission was a later onset phenotype as compared with other assessments of motor unit numbers, muscle contractility, and frailty which showed alterations at 20 months of age. Ex vivo NMJ recordings demonstrated no reduction of endplate current amplitude in support of reduced muscle fiber excitability as the cause of failed NMJ transmission in aged mice. Improved understanding of age-related neurodegeneration will likely have important implications in designing novel therapeutic interventions specific for different stages of sarcopenia. Our findings suggest reduced muscle excitability may be a potential therapeutic target for improvement of physical function in older adults.

Modelling an Adaptive Cluster Head Positioning Based Map Reducing Strategy for Data Transmission in Medical IoT

Internet-of-things (IoT) based health monitoring systems have turned out to be an interesting topic to enhance quality of health care services. Moreover, there is no advanced IoT based continuous monitoring of glucose systems in real time and some prevailing techniques have numerous limitations. Here, a continuous and invasive glucose monitoring system for transmitting the condition of individuals simultaneously utilizing IoT is modelled and a general system architectural design for processing back end systems to provide body temperature, real time glucose and contextual data in human readable and graphical forms to the physicians or patients is anticipated. As well, a protocol designs for monitoring the continuous data from IoT devices in order to overcome the short comings of existing methods is provided. The design of an energy efficient routing algorithm is a hot topic in the research of IoT based Data mining. Cluster Heads (CH) form backbone of inter-cluster communication. The selection of reliable and efficient cluster head is another important issue. In most of the clustering process, failure of CH occurs due to energy depletion and if the distance between sink and CH is more, it ultimately leads to failure in transmission. During transmission, nodes may fail that means sudden energy loss or node gets out of coverage. Due to relaying high data traffic, some of nodes quickly exhaust their energy and increase the risk of node failure. As a baseline to node failure, data packet loss also occurs in a CH due to congestion and poor link quality. Hence, one of the most crucial feature in designing a protocol is to minimize energy consumption for betterment of network functioning. Here, a clustering routing protocol based on data mining techniques is applied for sensor nodes in medical field called Adaptive Positioning of Cluster Head based Map reducing (APCH-MR) is proposed. Routing table based code book is generated for privacy concern, in which the process of mapping and reducing the data for dissemination is performed. The simulated outcomes depicts that the total number of packets transmitted in round 500 is 11200, total number of dead nodes during round 500 is 58, and time consumed by nodes at 500 rounds is 0.3751s respectively. The proposed method shows better trade off in contrast to conventional techniques.

Modelling an Adaptive Cluster Head Positioning Based Map Reducing Strategy for Data Transmission in Medical IoT

Internet-of-things (IoT) based health monitoring systems have turned out to be an interesting topic to enhance quality of health care services. Moreover, there is no advanced IoT based continuous monitoring of glucose systems in real time and some prevailing techniques have numerous limitations. Here, a continuous and invasive glucose monitoring system for transmitting the condition of individuals simultaneously utilizing IoT is modelled and a general system architectural design for processing back end systems to provide body temperature, real time glucose and contextual data in human readable and graphical forms to the physicians or patients is anticipated. As well, a protocol designs for monitoring the continuous data from IoT devices in order to overcome the short comings of existing methods is provided. The design of an energy efficient routing algorithm is a hot topic in the research of IoT based Data mining. Cluster Heads (CH) form backbone of inter-cluster communication. The selection of reliable and efficient cluster head is another important issue. In most of the clustering process, failure of CH occurs due to energy depletion and if the distance between sink and CH is more, it ultimately leads to failure in transmission. During transmission, nodes may fail that means sudden energy loss or node gets out of coverage. Due to relaying high data traffic, some of nodes quickly exhaust their energy and increase the risk of node failure. As a baseline to node failure, data packet loss also occurs in a CH due to congestion and poor link quality. Hence, one of the most crucial feature in designing a protocol is to minimize energy consumption for betterment of network functioning. Here, a clustering routing protocol based on data mining techniques is applied for sensor nodes in medical field called Adaptive Positioning of Cluster Head based Map reducing (APCH-MR) is proposed. Routing table based code book is generated for privacy concern, in which the process of mapping and reducing the data for dissemination is performed. The simulated outcomes depicts that the total number of packets transmitted in round 500 is 11200, total number of dead nodes during round 500 is 58, and time consumed by nodes at 500 rounds is 0.3751s respectively. The proposed method shows better trade off in contrast to conventional techniques.

Effectiveness and failure rate of the varicella vaccine in an outbreak in Jiangsu, China: a 1:2 matched case-control study

ABSTRACT Background: The varicella vaccine is not included in the national childhood immunization schedules in China, although one-dose varicella vaccine has been suggested for susceptible children aged 1–12 years in Jiangsu Province. However, varicella epidemics and outbreaks are frequently reported. We investigated a varicella outbreak in an elementary school to explore the risk factors for varicella transmission and vaccine failure. Methods: A 1:2 matched case-control study was carried out. Participant data were collected with standardized questionnaires. For each case, we enrolled two controls: a subject with high exposure in the same classroom as the case and a subject with low exposure in a different classroom. Data regarding vaccination status and medical and exposure histories were analyzed. Results: Fifty-one cases were reported during the outbreak; 26 cases (51%) were breakthrough varicella. Varicella vaccine immunization history (P < .001, OR = 0.19, 95% CI = 0.08–0.45) and the presence of siblings (P = .037, OR = 0.45, 95% CI = 0.21–0.95) were protective factors in preventing varicella infection. Contact with varicella patients increased the risk of varicella infection (P = .028, OR = 3.39, 95% CI = 1.14–10.09). Breakthrough varicella cases tended to present a milder rash (P = .049), fewer complications (P = .02), fewer rash sites (P = .02) and a shorter duration of active lesions (P = .001). One pneumonia case and one encephalitis case were reported in breakthrough cases. Age <15 months at the time of vaccination increased the risk of breakthrough varicella (P = .012). The adjusted vaccine effectiveness was 81%. Conclusions: One-dose varicella vaccine is effective at alleviating clinical manifestations. The moderate coverage provided by one dose cannot prevent varicella outbreaks, and vaccination after 15 months of age should be considered in the immunization schedule; a two-dose strategy is highly recommended.

Deep Learning Empowered Task Offloading for Mobile Edge Computing in Urban Informatics

Led by industrialization of smart cities, numerous interconnected mobile devices, and novel applications have emerged in the urban environment, providing great opportunities to realize industrial automation. In this context, autonomous driving is an attractive issue, which leverages large amounts of sensory information for smart navigation while posing intensive computation demands on resource constrained vehicles. Mobile edge computing (MEC) is a potential solution to alleviate the heavy burden on the devices. However, varying states of multiple edge servers as well as a variety of vehicular offloading modes make efficient task offloading a challenge. To cope with this challenge, we adopt a deep Q-learning approach for designing optimal offloading schemes, jointly considering selection of target server and determination of data transmission mode. Furthermore, we propose an efficient redundant offloading algorithm to improve task offloading reliability in the case of vehicular data transmission failure. We evaluate the proposed schemes based on real traffic data. Results indicate that our offloading schemes have great advantages in optimizing system utilities and improving offloading reliability.

Nonrandom associations of maternally transmitted symbionts in insects: The roles of drift versus biased cotransmission and selection.

Virtually all higher organisms form holobionts with associated microbiota. To understand the biology of holobionts we need to know how species assemble and interact. Controlled experiments are suited to study interactions between particular symbionts, but they only accommodate a tiny portion of the diversity within each species. Alternatively, interactions can be inferred by testing if associations among symbionts in the field are more or less frequent than expected under random assortment. However, random assortment may not be a valid null hypothesis for maternally transmitted symbionts since drift alone can result in associations. Here, we analyse a European field survey of endosymbionts in pea aphids (Acyrthosiphon pisum), confirming that symbiont associations are pervasive. To interpret them, we develop a model simulating the effect of drift on symbiont associations. We show that drift induces apparently nonrandom assortment, even though horizontal transmissions and maternal transmission failures tend to randomise symbiont associations. We also use this model in the approximate Bayesian computation framework to revisit the association between Spiroplasma and Wolbachia in Drosophila neotestacea. New field data reported here reveal that this association has disappeared in the investigated location, yet a significant interaction between Spiroplasma and Wolbachia can still be inferred. Our study confirms that negative and positive associations are pervasive and often induced by symbiont-symbiont interactions. Nevertheless, some associations are also likely to be driven by drift. This possibility needs to be considered when performing such analyses, and our model is helpful for this purpose.

Deep Sequencing Reveals the Characteristics of Hepatitis B Virus (HBV) S Region in Vertical Transmission and the Influence of Mutations on Vaccination Failure

Background: Immune escape mutation is a major reason for vaccination failure in vertical transmission of hepatitis B virus (HBV). Objectives: The aim of the current study was to explore the characteristics of HBV S region gene in vertical transmission and the influence of mutations on vaccination failure in HBV S region gene. Methods: A total of nine mother-child pairs with chronic HBV were recruited in this study, and all of the children received the vaccine. Next-generation sequencing (NGS) was used to investigate the sequences of HBV S gene from the mother and children. Results: The analysis of the sequencing data showed that all mother-child pairs are genotype B and genotype C mixed infection and the dominant genotype did not change in vertical transmission, and the consensus sequences of mothers and children were highly similar. Furthermore, the diversity of most amino acid sites had a small difference between mothers and children, and the mutations shared by mothers and children made up a high proportion of children’s mutations; the rate was 83.13% ± 8.45%. Also, the research found many mutations that could cause immune escape in major hydrophilic region. Especially in “a” determinant, sC137S or sC139Y, which had an important influence on the structure of “a” determinant, were observed in all mother-child pairs. Conclusions: All the above results indicated that HBV S gene was highly conserved in vertical transmission, and these immune escape mutations that pre-exist in mothers were transmitted to children and resulted in vaccination failure.

Dynamic behavior analysis of an internet flow interaction model under cascading failures.

Cascading failures in the internet have attracted recent attention due to their unpredictability and destructive consequences. Exploring the failure behavior patterns is necessary because they can provide effective intervention approaches to prevent huge network disasters. To analyze internet flow behaviors during cascading failures (chain reactions in router and link failures), we characterize the internet as two coupled networks, the router network and the flow network. Here the flow network is an abstract representation of data correlations obtained from the router network. We use this coupled network to build a cascading failure model for studying flow transmission and competition, which is reflected in bandwidth competition given by limited link capacity. We first study the dependency between routers and flows to explore the flow transmission efficiency when a failure event occurs. Moreover, we find that rerouting enables flow competition area (the number of flows with which one flow has a competitive relationship) to initially remain stable during a failure episode, but that it then quickly drops due to poor physical network connectivity. Additionally, in the early stage after the failure event, the degree of flow competition sharply increases because of the growing number of the flows and congestion. Subsequently, the flow competition decreases due to the failure of flow transmission.