Photocatalytic hydrogen production with aid of simultaneous metal deposition using titanium dioxide from aqueous glucose solution

The photocatalytic hydrogen production with aid of simultaneous metal deposition using TiO₂ was investigated in biomass glucose solution. Because the hydrogen production was very trace with pure TiO₂, the simultaneous metal deposition was applied into the glucose solution. The photocatalytic H₂ production activity with TiO₂ was significantly enhanced by simultaneous metal deposition for Au and Pd. The experimental factors such as glucose concentration, metal ion concentration and reaction temperature were investigated. The photocatalytic hydrogen production increased with increasing the concentration of glucose, and it followed Langmuir–Hinshelwood mechanism. Under the optimal conditions, the photocatalytic hydrogen generations from aqueous glucose solution with in-situ Au and Pd deposited TiO₂ were about 203 and 362 times larger compared with those observed with pure TiO₂. The enhanced photocatalytic activity could be explained in terms of reduced electron hole recombination via electron transfer from conductance band of TiO₂ to metal.     

Neferine from Nelumbo nucifera induces autophagy through the inhibition of PI3K/Akt/mTOR pathway and ROS hyper generation in A549 cells

Previously we have reported that neferine from the medicinal plant Nelumbo nucifera, inhibited cancer cell proliferation by inducing apoptosis. The present study was focused on the action mechanism of neferine in inducing autophagy in lung cancer cells. Neferine markedly inhibited A549 cell proliferation in a dose dependent manner. Acidic vesicular accumulation was observed in neferine treated cells as an indication of autophagy. Neferine could induce the conversion of LC3B-I to LC3B-II without affecting the expression levels of PI3KCIII and Beclin1. It has been observed that neferine mediated autophagy is dependent on inhibition of PI3K/Akt/mTOR signaling by neferine. Neferine treatment could also lead to the ROS hypergeneration and depletion of cellular antioxidant, GSH. The results demonstrate that neferine-induced autophagy is mediated through ROS hypergeneration and mTOR inhibition. Taken together, the present study unveils a novel mechanism of action of neferine on lung cancer cells in the induction of autophagy.     

Defense against Sybil attacks and authentication for anonymous location-based routing in MANET

In MANET, providing authentication and security to location-based routing is a big task. To overcome this problem, in this paper, we proposed a defense against Sybil attacks and authentication for anonymous location-based routing in MANET. Each random forwarder has a table of RSS values estimated from the previous message exchanges across a zone to detect the Sybil attack. The difference in RSS values of two neighboring nodes is estimated based on which the node’s arrival angle into the zone is detected. Depending on the arrival angle, the nodes can be categorized as safety zone and caution zone. The messages exchanged between the RFs and senders can be protected by means of group signature. Finally, misrouting packet drop attack is detected and eliminated by using ant colony optimization technique. By simulation results, we show the proposed technique reduces the packet drop due to attacks, thereby increasing the delivery ratio.     

Emission analysis on compression ignition engine fueled with lower concentrations of Pithecellobium dulce biodiesel‐diesel blends

The present study investigates the effect of Pithecellobium dulce biodiesel (PDBD) blends with diesel fuel on compression ignition (CI) engine emissions. Initially, PDBD was prepared by using a base transesteri?cation process. The GC‐MS, ¹H NMR, and Fourier transform infrared characterization of PDBD was carried out, and fuel properties were determined. The experiments were conducted on a single cylinder, CI engine using three blended fuels: PDBD5 (5% biodiesel and 95% diesel), PDBD10 (10% biodiesel and 90% diesel), and PDBD20 (20% biodiesel and 80% diesel). The experimental outcomes revealed that 20% of PDBD reduces 19.64% carbon monoxide, 17.64% hydrocarbon, and 6.73% oxides of nitrogen emissions. Furthermore, from this study, it was inferred that the PDBD20 blend could be used as an alternative fuel for CI engines with no modi?cations in engine design.     

Rule‐Based Anomaly Detection Technique Using Roaming Honeypots for Wireless Sensor Networks

Because the nodes in a wireless sensor network (WSN) are mobile and the network is highly dynamic, monitoring every node at all times is impractical. As a result, an intruder can attack the network easily, thus impairing the system. Hence, detecting anomalies in the network is very essential for handling efficient and safe communication. To overcome these issues, in this paper, we propose a rule‐based anomaly detection technique using roaming honeypots. Initially, the honeypots are deployed in such a way that all nodes in the network are covered by at least one honeypot. Honeypots check every new connection by letting the centralized administrator collect the information regarding the new connection by slowing down the communication with the new node. Certain pre‐defined rules are applied on the new node to make a decision regarding the anomality of the node. When the timer value of each honeypot expires, other sensor nodes are appointed as honeypots. Owing to this honeypot rotation, the intruder will not be able to track a honeypot to impair the network. Simulation results show that this technique can efficiently handle the anomaly detection in a WSN.     

Redundant node identification using Siamese neural network to enhance the availability in visual sensor network

Many monitoring applications related to surveillance, tracking and multipurpose visual monitoring have taken into consideration the use of wireless visual sensor networks. When sensors are deployed over a monitored field that could potentially damage the monitoring capability and availability in the visual sensor network. In order to overcome these issues, faulty nodes are identified and replaced by redundant node based on Siamese network in this research. Initially, camera nodes are randomly deployed in the visual sensor network, and the data are received from the network through gateway. To identify the redundant nodes, initially, the frames are divided into equivalent time slot, and then, Siamese network is utilized to identify the redundant nodes in a network. Siamese neural network is type of convolutional neural network that is utilized to recognize the similar images in the network. After that, faulty nodes are identified based on some parameters such as entropy, energy, transmission delay and network coverage. If the average energy, entropy, transmission delay and network coverage are below the threshold value, then the node is identified as faulty node. Finally, replace the faulty node with redundant node to enhance the availability in the visual sensor network for critical monitoring applications. The simulation analysis shows that the developed approach takes 772 s to identify redundant node and take 27 s to identify fake nodes and the developed method is executed at 1308 s. Thus, this prediction model helps to improve the coverage quality of target-based monitoring in order to achieve availability.     

Stochastic dynamic programming model for optimal resource allocation in vehicular ad hoc networks

Vehicular ad hoc network (VANET) is an emerging trend where vehicles communicate with each other and possibly with a roadside unit to assist various applications like monitoring, managing and optimizing the transportation system. Collaboration among vehicles is significant in VANET. Resource constraint is one of the great challenges of VANETs. Because of the absence of centralized management, there is pitfall in optimal resource allocation, which leads to ineffective routing. Effective reliable routing is quite essential to achieve intelligent transportation. Stochastic dynamic programming is currently employed as a tool to analyse, develop and solve network resource constraint and allocation issues of resources in VANET. We have considered this work as a geographical-angular-zone-based two-phase dynamic resource allocation problem with a homogeneous resource class. This work uses a stochastic dynamic programming algorithm based on relaxed approximation to generate optimal resource allocation strategies over time in response to past task completion status history. The second phase resource allocation uses the observed outcome of the first phase task completion to provide optimal viability in resulting decisions. The proposed work will be further extended for the scenario that deals with heterogeneous resource class. Simulation results show that the proposed scheme works significantly well for the problems with identical resources.     

Energy Based Random Repeat Trust Computation in Delay Tolerant Network

As the use of mobile devices continues to rise, trust administration will significantly improve security in routing the guaranteed quality of service (QoS) supply in Mobile Ad Hoc Networks (MANET) due to the mobility of the nodes. There is no continuance of network communication between nodes in a delay-tolerant network (DTN). DTN is designed to complete recurring connections between nodes. This approach proposes a dynamic source routing protocol (DSR) based on a feed-forward neural network (FFNN) and energy-based random repetition trust calculation in DTN. If another node is looking for a node that swerved off of its path in this situation, routing will fail since it won’t recognize it. However, in the suggested strategy, nodes do not stray from their pathways for routing. It is only likely that the message will reach the destination node if the nodes encounter their destination or an appropriate transitional node on their default mobility route, based on their pattern of mobility. The EBRRTC-DTN algorithm (Energy based random repeat trust computation) is based on the time that has passed since nodes last encountered the destination node. Compared to other existing techniques, simulation results show that this process makes the best decision and expertly determines the best and most appropriate route to send messages to the destination node, which improves routing performance, increases the number of delivered messages, and decreases delivery delay. Therefore, the suggested method is better at providing better QoS (Quality of Service) and increasing network lifetime, tolerating network system latency.     

Energy Efficient Enhanced OLSR Routing Protocol Using Particle Swarm Optimization with Certificate Revocation Scheme for VANET

In Vehicular ad-hoc networks (VANETs), routing and security are the mainchallenges. In our previous work, we have presented cluster-based secure communication with the certificate revocation scheme for securable communication between the vehicles.Cluster formation is done using the trust degree of each vehicle and this trust degree is calculated based on the direct and indirect trust degree of each vehicle. Information of eachvehicle is gathered by the corresponding cluster head (CH) in a cluster. This information is maintained by the Certificate Revocation List (CRL) in the Certificate Authority (CA). CA isolates a vehicle as an attacked node if it has less trust degree than the threshold trust value and it invalidates the certificate of attacked or revoked nodes. Before transmission, each vehicle in a cluster validates its certificate with the support of CA. After the validation, the other challenge of VANET i.e., efficient route is to be established so that Energy efficient enhanced OLSR routing protocol using Particle Swarm Optimization (PSO) algorithm is presented in this paper. After the establishment of the efficient route, the vehicle deploys the symmetric cryptography approach for securable transmission. Simulation results show that the performance of our proposed approach outperforms the performance of existing work in terms of energy efficiency.