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111.
Wireless Sensor Network (WSN) is considered to be one of the fundamental technologies employed in the Internet of things (IoT); hence, enabling diverse applications for carrying out real-time observations. Robot navigation in such networks was the main motivation for the introduction of the concept of landmarks. A robot can identify its own location by sending signals to obtain the distances between itself and the landmarks. Considering networks to be a type of graph, this concept was redefined as metric dimension of a graph which is the minimum number of nodes needed to identify all the nodes of the graph. This idea was extended to the concept of edge metric dimension of a graph G, which is the minimum number of nodes needed in a graph to uniquely identify each edge of the network. Regular plane networks can be easily constructed by repeating regular polygons. This design is of extreme importance as it yields high overall performance; hence, it can be used in various networking and IoT domains. The honeycomb and the hexagonal networks are two such popular mesh-derived parallel networks. In this paper, it is proved that the minimum landmarks required for the honeycomb network HC(n), and the hexagonal network HX(n) are 3 and 6 respectively. The bounds for the landmarks required for the hex-derived network HDN1(n) are also proposed.  相似文献   
112.
Electromagnetic (EM) waves used to send signals under seawater are normally restricted to low frequencies () because of sudden exponential increases of attenuation () at higher . The mathematics of EM wave propagation in seawater demonstrate dependence on relative permeability (), relative permittivity (), conductivity (), and of transmission. Estimation of and based on the W. Ellison interpolation model was performed for averaged real‐time data of temperature () and salinity () from 1955 to 2012 for all oceans with latitude/longitude points and 101 depth points up to 5500 m. Estimation of parameters such as real and imaginary parts of , , , , loss tangent (tan ), propagation velocity (), phase constant (), and contributes to absorption loss () for seawater channels carried out by using normal distribution fit in the 3 GHz–40 GHz range. We also estimated total path loss () in seawater for given transmission power and antenna (dipole) gain. MATLAB is the simulation tool used for analysis.  相似文献   
113.
In this article, a new t‐chart based on generalized multiple dependent state (GMDS) sampling is proposed for efficient monitoring of a process by assuming that the time between events follows the exponential distribution. The proposed t‐chart has two pair of control limits and utilizes the past sample information with the current sample information. The control chart coefficients are estimated by considering different values of the in‐control average run lengths. The proposed t‐chart is compared with the existing chart by using the out‐of‐control average run length and extra quadratic loss function. The comparison reveals that the proposed charting strategy has better shift detection ability in process mean. An illustrative example is given for the practical implementation of the proposed chart.  相似文献   
114.
Intelligent Service Robotics - The role of a human assistant, such as receptionist, is to provide specific information to the public. Questions asked by the public are often context dependent and...  相似文献   
115.
Bulletin of Engineering Geology and the Environment - Most of the surface wave-based geophysical methods require an accurate estimate of the shear wave velocity (Vs) for geotechnical site...  相似文献   
116.
Wireless Personal Communications - Non-orthogonal multiple access (NOMA) scheme, potentially enabling high spectral efficiency, is one of the key technological innovations in the 5th generation...  相似文献   
117.
Wireless Personal Communications - Partial Discharge (PD) checking is a standout amongst the best technique for insulation condition evaluation of HV power system. PD releases inside a power...  相似文献   
118.
119.
Recently, the world is facing the terror of the novel corona-virus, termed as COVID-19. Various health institutes and researchers are continuously striving to control this pandemic. In this article, the SEIAR (susceptible, exposed, infected, symptomatically infected, asymptomatically infected and recovered) infection model of COVID-19 with a constant rate of advection is studied for the disease propagation. A simple model of the disease is extended to an advection model by accommodating the advection process and some appropriate parameters in the system. The continuous model is transposed into a discrete numerical model by discretizing the domains, finitely. To analyze the disease dynamics, a structure preserving non-standard finite difference scheme is designed. Two steady states of the continuous system are described i.e., virus free steady state and virus existing steady state. Graphical results show that both the steady states of the numerical design coincide with the fixed points of the continuous SEIAR model. Positivity of the state variables is ensured by applying the M-matrix theory. A result for the positivity property is established. For the proposed numerical design, two different types of the stability are investigated. Nonlinear stability and linear stability for the projected scheme is examined by applying some standard results. Von Neuman stability test is applied to ensure linear stability. The reproductive number is described and its pivotal role in stability analysis is also discussed. Consistency and convergence of the numerical model is also studied. Numerical graphs are presented via computer simulations to prove the worth and efficiency of the quarantine factor is explored graphically, which is helpful in controlling the disease dynamics. In the end, the conclusion of the study is also rendered.  相似文献   
120.
Single layer fuel cell (SLFC) is a novel breakthrough in energy conversion technology. This study is to realize the physical-electrochemical co-driving mechanism of a single component device composed of mixed ionic and semiconductor material. This paper is focused on investigating the mechanism and characterization of synthesized nanocomposite BaZr0.7Sm0.1Y0.2O3?δ (BZSY)–La0.8Sr0.2Co0.2Fe0.8O3?δ (LSCF) in proportion 1:1 and 3:7 for SLFC. The crystallographic structure and morphology is studied with X-ray diffraction (XRD) and scanning electron microscopy (SEM). The nano-particles lie in the range of 100–210 nm. Ultraviolet (UV) and electrochemical impedance spectroscopy (EIS) is used to analyze the semiconducting nature of nanocomposite (BZSY–LSCF). The performance of SLFC was carried out at different temperatures ranging between 400 and 650 °C. The mixed conductivity of the synthesized material was about 2.3 S cm?1. The synergic effect of junction and energy band gap towards charge separation as well as the promotion of ion transport by junction built in field contributes to the working principle and high power output in the SLFC.  相似文献   
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