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The purpose of this paper is energy consumption and security. To extend the sensor’s life span, saving the energy in a sensor is important. In this paper, biosensors are implanted or suited on the human body, and then, transposition has been applied for biosensors for reducing the sensor distance from the sink node. After transposition path loss has been calculated, security is maintained and also compared the results with the existing strategies.

Nowadays, one of the most emergent technologies is wireless body area network (WBAN), which represents to improve the quality of life and also allow for monitoring the remote patient and other health-care applications. Traffic routing plays a main role together with the relay nodes, which is used to collect the biosensor’s information and send it towards the sink.

To calculate the distance and observe the position, Euclidean distance technique is used. Path loss is the main parameter, which is needed to reduce for making better data transmission and to make the network stability. Routing protocols can be designed, with the help of proposed values of sensors locations in the human body, which gives good stability of network and lifetime. It helps to achieve as the less deplete energy.

This scheme is compared with the two existing schemes and shows the result in terms of parameter path loss. Moreover, this paper evaluated a new method for improving the security in WBAN. The main goal of this research is to find the optimal sensor location on the body and select the biosensor positions where they can get less energy while transmitting the data to the sink node, increasing the life span in biosensors, decreasing memory space, giving security, controlling the packet complexity and buffer overflow and also fixing the damages in the existing system.

The purpose of this paper is to enhance the network lifetime of WSN. In wireless sensor network (WSN), the sensor nodes are widely deployed in a terrestrial environment to sense and evaluate the physical circumstances. The sensor node near to the sink will deplete more energy faster than other nodes; hence, there arises an energy hole and network partitioning problem in stationary sink-based WSN. Even though many mobile sink-based WSN is formulated to mitigate energy hole, inappropriate placement of sink leads to packet drop and affect the network lifetime of WSN. Therefore, it is necessary to have an efficient sink mobility approach to prevent an aforesaid problem.

In this paper, zone-based sink mobility (ZBSM) approach is proposed in which the zone formation along with controlled sink mobility is preferred for energy hole mitigation and optimal sink node placement. In ZBSM, the sink decides to move toward strongly loaded zone (SLZ) for avoiding network partitioning problems where the selection of SLZ can be carried out by using Fuzzy Logic.

The performance results confirm that the proposed scheme reduces energy consumption as well as enhances the network lifetime compared with an existing scheme.

A new optimal sink node placement is proposed to enhance the network lifetime and packet delivery ratio of WSN.

With the increasing demand for lightweight parts, the quality of the inner structure gained growing attention from different kinds of fields. As the quality of the overhanging surface was one of the most important factors affecting inner structure formation, its quality still needs to improve. This paper aims to clarify the change of the overhanging surface quality caused by different bending angles.

The structure of the inner hole was redesigned according to the different performances of the overhanging and side inner surface. The experimental results revealed why different surface qualities can be seen under different bending angles. According to the experimental data, the inner structure was redesigned to increase its overall performance.

The results revealed that when the bending angle was small, the slope of the overhanging surface increased which lead to the decreasing length of the powder-supported layer. However, less space on bending angle resulted in the accumulation of unmelted powder which leads to the increasing of sinking distance. When the bending angle was too large, the slope of the overhanging surface decreased and the length of the molten pool which was supported by powder increased. It resulted in the sinking of the molten pool caused by the gravity of powder and its attachment.

This paper is the first work to study the relationship between bending angle and overhanging surface quality as far as the authors know. The different performances of left and right overhanging surfaces also have not been revealed in other research studies to the best of the knowledge.

The purpose of this paper is to detect and control the liquid‐level of stereolithography apparatus precisely.

A brightness‐variable laser source is adopted to remove the computational error of divider and a closed‐loop circuit is set to measure the terminal voltage directly proportional to the output current of photosensitive devices. It employs a sinking‐block device to control the liquid‐level.

The precise calibration result of this detecting device indicates that the resolution of the liquid‐level detection can reach ±1.5 μm.

This sinking‐block style liquid‐level control device can allow for the liquid‐level wave reduced from ±45 to ±15 μm.

A boundary integral technique is developed to study the free surface flow of a steady, two‐dimensional, incompressible, irrotational and inviscid fluid flow which is produced by two submerged sinks (or sources) which are of equal strength, placed along a solid horizontal boundary with a stagnation point on the free surface in a two layer stratified fluid in the presence of gravity. A special form of the Riemann‐Hilbert problem, namely the Dirichlet boundary problem, is applied in the derivation of the governing non‐linear boundary integral‐differential equations which are solved for the fluid velocity on the free surface and this involves the use of an interpolative technique and an iterative process. Results have been obtained for the free surface flow for various values of the Froude number and sink locations on the solid horizontal boundary and we have also studied the largest value of the Froude number for which no convergent solutions are possible, namely the critical Froude number. We have found that the free surface profile is dependent on two parameters, namely the Froude number on the free surface and the non‐dimensional distance between the two sinks.

A new wire arc additive manufacturing (WAAM) process combined with gravity-driven powder feeding was developed to fabricate components of tungsten carbide (WC)-reinforced iron matrix composites. The purpose of this study was to investigate the particle transportation mechanism during deposition and determine the effects of WC particle size on the microstructure and properties of the so-fabricated component.

Thin-walled samples were deposited by the new WAAM using two WC particles of different sizes. A series of in-depth investigations were conducted to reveal the differences in the macro morphology, microstructure, tensile performance and wear properties.

The results showed that inward convection and gravity were the main factors affecting WC transportation in the molten pool. Large WC particles have higher ability than small particles to penetrate into the molten pool and survive severe dissolution. Small WC particles were more likely to be completely dissolved around the top surface, forming a thicker region of reticulate (Fe, W)₆C. Large WC particles can slow down the inward convection more, thereby leading to an increase in width and a decrease in the layer height of the weld bead. The mechanical properties and wear resistance significantly increased owing to reinforcement. Comparatively, samples with large WC particles showed inferior tensile properties owing to their higher susceptibility to cracks.

Fabricating metal matrix composites through the WAAM process is a novel concept that still requires further investigation. Apart from the self-designed gravity-driven powder feeding, the unique aspects of this study also include the revelation of the particle transportation mechanism of WC particles during deposition.

The purpose of this paper is to prepare alginate‐pectin‐starch containing matrices expanded by the generation of carbon dioxide, from carbonates when in contact with acids, characterise their structure in vitro and to assess their capacity to provide satiety in vivo.

For in vitro characterisation, carbon dioxide expanded polysaccharide matrices (rafts) were prepared in HCl and their structural strength was measured in terms of their capacity to resist breakage in a model test system. For in vivo trials, 12 healthy volunteers (mixed sex, aged 25‐55) were recruited to take part in the three‐part trial. Each part lasted for one week where volunteers consumed polysaccharides (in 50 ml water) with or without rafting salts (carbonates), or water (as a control). Effects on satiety, reduction of food intake and any change to body weight were evaluated with the volunteers.

The in vitro results showed that aqueous solution/dispersions (50 ml) of alginate‐pectin‐starch matrices produced rafts in hydrochloric acid (pH < 2), where increasing the ratio of carbonates to polysaccharides (range from 0.25:1 to 1.5:1, w/w) provided increased floatation capability but reducing gel strength. These rafts were stable for over 24 h at room temperature within 0.05‐0.5 M HCl. For in vivo “satiety” studies, when volunteers consumed (daily) aliquots of the polysaccharide mixture plus flavour and sweetener without carbonates 2.5 h after lunch, they felt the onset of hunger on average 186 ± 68 min after consumption of the polysaccharides. This was not significantly different from a water only control (onset of hunger at 165 ± 47 min). When polysaccharides plus flavour sweetener and carbonates were consumed, however, volunteers reported feeling the onset of hunger at 224 ± 62 min on average after consumption which was significantly different from the water control (p < 0.001), or the polysaccharides without carbonates (p < 0.01). When consuming the polysaccharide rafting format, half of the volunteers reported a reduction in size of their evening meal.

These data indicate that the alginate‐pectin‐starch combination with carbonate salts in a “gastric rafting format” provide a potential approach in the management of body weight and obesity.

The purpose of this paper is to explore grid‐based routing in wireless sensor networks and to compare the energy available in the network over time for different grid sizes.

The test area is divided into square‐shaped grids of certain length. Energized nodes are placed randomly in the terrain area with the sink node in a fixed position. One node per grid is elected as the leader node based on the highest energy level and the proximity to the centre of the grid. The sink node floods the network to identify a path from sink to source. The path from the sink to the source through the leader nodes are computed using three different methods: shortest path; leader nodes which have the highest energy; and leader nodes based on their received signal strength (RSS) indicator values. After the path is computed, transmission of data is continued until the leader nodes run out of energy. New leader nodes are then elected using the same mechanism to replace the depleted ones.

Identified the optimal grid size to minimize the energy consumption in sensor networks and to extend the network lifetime. Also proposed is a new routing protocol which identifies routes based on energy threshold and RSS threshold.

The use of RSS threshold is identified to be the good metric for path selection in routing the data between source and the sink.

Simulator software and the protocol developed can be used for in optimizing energy efficiency in sensor networks.

This work contributes to the discussion on uniform and non‐uniform grid sizes and emphasizes a new method for reducing the energy consumption by identifying an optimum grid size. It also utilizes bursty data for simulation.

In a wireless sensor network (WSN), the sensor nodes are distributed in the network, and in general, they are linked through wireless intermediate to assemble physical data. The nodes drop their energy after a specific duration because they are battery-powered, which also reduces network lifetime. In addition, the routing process and cluster head (CH) selection process is the most significant one in WSN. Enhancing network lifetime through balancing path reliability is more challenging in WSN. This paper aims to devise a multihop routing technique with developed IIWEHO technique.

In this method, WSN nodes are simulated originally, and it is fed to the clustering process. Meanwhile, the CH is selected with low energy-based adaptive clustering model with hierarchy (LEACH) model. After CH selection, multipath routing is performed by developed improved invasive weed-based elephant herd optimization (IIWEHO) algorithm. In addition, the multipath routing is selected based on certain fitness functions like delay, energy, link quality and distance. However, the developed IIWEHO technique is the combination of IIWO method and EHO algorithm.

The performance of developed optimization method is estimated with different metrics, like distance, energy, delay and throughput and achieved improved performance for the proposed method.

This paper presents an effectual multihop routing method, named IIWEHO technique in WSN. The developed IIWEHO algorithm is newly devised by incorporating EHO and IIWO approaches. The fitness measures, which include intra- and inter-distance, delay, link quality, delay and consumption of energy, are considered in this model. The proposed model simulates the WSN nodes, and CH selection is done by the LEACH protocol. The suitable CH is chosen for transmitting data through base station from the source to destination. Here, the routing system is devised by a developed optimization technique. The selection of multipath routing is carried out using the developed IIWEHO technique. The developed optimization approach selects the multipath depending on various multi-objective functions.

Load balancing is an effective enhancement to the proposed routing protocol, and the basic idea is to share traffic load among cluster members to reduce the dropping probability due to queue overflow at some nodes. This paper aims to propose a novel hierarchical approach called distributed energy efficient adaptive clustering protocol (DEACP) with data gathering, load-balancing and self-adaptation for wireless sensor network (WSN). The authors have proposed DEACP approach to reach the following objectives: reduce the overall network energy consumption, balance the energy consumption among the sensors and extend the lifetime of the network, the clustering must be completely distributed, the clustering should be efficient in complexity of message and time, the cluster-heads should be well-distributed across the network, the load balancing should be done well and the clustered WSN should be fully connected. Simulations show that DEACP clusters have good performance characteristics.

A WSN consists of large number of wireless capable sensor devices working collaboratively to achieve a common objective. One or more sinks [or base stations (BS)] which collect data from all sensor devices. These sinks are the interface through which the WSN interacts with the outside world. Challenges in WSN arise in implementation of several services, and there are so many controllable and uncontrollable parameters (Chirihane, 2015) by which the implementation of WSN is affected, e.g. energy conservation. Clustering is an efficient way to reduce energy consumption and extend the life time of the network, by performing data aggregation and fusion to reduce the number of transmitted messages to the BS (Chirihane, 2015). Nodes of the network are organized into the clusters to process and forwarding the information, while lower energy nodes can be used to sense the target, and DEACP makes no assumptions on the size and the density of the network. The number of levels depends on the cluster range and the minimum energy path to the head. The proposed protocol reduces the number of dead nodes and the energy consumption, to extend the network lifetime. The rest of the paper is organized as follows: An overview of related work is given in Section 2. In Section 3, the authors propose an energy efficient level-based clustering routing protocol (DEACP). Simulations and results of experiments are discussed in Section 4. In Section 5, the authors conclude the work presented in this paper and the scope of further extension of this work.

The authors have proposed the DEACP approach to reach the following objectives: reduce the overall network energy consumption, balance the energy consumption among the sensors and extend the lifetime of the network, the clustering must be completely distributed, the clustering should be efficient in complexity of message and time, the cluster-heads should be well-distributed across the network, the load balancing should be done well, the clustered WSN should be fully connected. Simulations show that DEACP clusters have good performance characteristics.