Salinity-Temperature Sensor using One-Dimensional Deformed Photonic Crystal

In this paper, new salinity and temperature sensor according to deformed one-dimensional photonic structure is proposed. The structure is constructed by alternating the couple of layers Air/Fused-Silica P-times. In the middle of the structure, a cavity containing the seawater is inserted to mesure its salinity and temperature. The Transfer Matrix Method (TMM) is used to simulate the wave-transmittance spectra. It is showed that, the quality factor (Q-factor) of the resonance peaks depends to the repetitive number (P) of layers. After that, the thickness of the layers is deformed by changing the deformation degree (h). The parameters P and h are optimized to get the maximal Q-factor with the minimal number of layers and structure’s thickness. The best sensitivity [[EQUATION]] of the proposed salinity sensor is 558.82 nm/RFIU with a detection limit of 0.0034 RFIU. In addition, the best sensitivity [[EQUATION]] of the designed temperature sensor is 600 nm/RFIU with a detection limit of 0.0005 RFIU.

FACTS Devices Loss Consideration in Placement Approach for Available Transfer Capability Enhancement

This paper incorporates Flexible AC Transmission System (FACTS) device loss with the general loss sensitivity equation for the determination of optimum location for its placement in deregulated power networks, with objectives of Available Transfer Capability (ATC) enhancement, bus voltage improvement and loss reduction. A detailed mathematical model in terms of circuit system parameters is presented based on FACTS loss amalgamation approach. Thyristor Controlled Series Capacitor (TCSC) FACTS device is considered for simulation and analysis because of its capability to control active power among other parameters. The TCSC location is established based on analysis of sensitivity factors obtained from partial derivatives of the resultant loss equations (including FACTS) with respect to control parameters. ATC values are obtained using ACPRDF method and with TCSC in place, these values are enhanced for different bilateral and multilateral power transactions. IEEE 5 Bus system is used for the demonstration of the effectiveness of this approach. Placement with this method resulted into ATC enhancement of more than 60% well above the values obtained when TCSC was placed with thermal limit method. In addition, a substantial bus voltage improvement of up to 3% deviation minimization as well as up to 10% active power loss reduction was recorded with this placement.

Development of Optimization Sensitivity Equation by Multiple Linear Regression and Correlation Analysis

Gas pipeline pressure-flow problem are affected by varieties of factors notably frictional pressure drop and other pressure drops components. These problems inevitably result in the reduction of the operating efficiency of gas pipelines by virtue of reduction in the line throughput and increased pressure drop along the line. It has been established that increased pressure drop will ultimately lead to increased pump power as well as higher cost of design, construction and operations of gas pipelines. These prevailing factors prompts the need to ascertain the stability and reliability of the optimal flow results. The develop sensitivity model prediction was hinged around ∆L/L (%) being zero. It invariably confirmed that the results of optimal flow capacity are more sensitive to changes in upstream and downstream pressures. It was least sensitive to pressure gradients. The governing conditions being that changes in pipe diameter, ∆D/D (%) and flow capacity, ∆Q/Q (%) were in the order of 5%.

Simple electrode configurations for probing deep organs using Electrical Bio-Impedance techniques

Tetrapolar Impedance Method (TPIM) and Focused Impedance Method (FIM) are two simple modalities of electrical bio-impedance measurement that could be employed to give useful physiological and diagnostic information of the human body. FIM is based on TPIM but uses a combination of two sets of TPIM, producing a focusing effect, which is useful to localize specific target organs. Most non-invasive electrical bio-impedance measurements based on TPIM and FIM use electrodes on one side of the body, outside the skin surface, which gives a shallow depth sensitivity. The sensitivity decreases with depth so that deep organs like lungs, heart, liver, stomach and bladder are not fully assessed through such measurements. Based on a long experience of studying electrical impedance methods, several qualitative ideas are presented in this article for probing deep organs using a few modified TPIM and FIM configurations. The suggestions are based on visualisations of both equipotentials and a popular sensitivity equation for transfer impedance, but not based on any quantitative analysis. Simulation and phantom studies based on these ideas may produce some practically useful electrode configurations for real life bio-impedance measurements. Bangladesh Journal of Medical Physics Vol.11 No.1 2018 P 1-15

A sensitivity study of relaxation parameter in Uzawa algorithm for the steady natural convection model

Purpose This paper aims to study the sensitivity of relaxation parameter in Uzawa method for the steady natural convection model. Design/methodology/approach Based on the continuous sensitivity equation method, associated sensitivity system is formed, which is solved by applying finite element method. Findings A decrease in sensitivity values of velocity, pressure and temperature is observed as the relaxation parameter increases. Originality/value The sensitivity study of relaxation parameter in Uzawa method is the first for the natural convection model, to the best of the authors’ knowledge. In fact, it is difficult to find an optimal relaxation parameter in the Uzawa method for the nonlinear problems. It is therefore important to understand how small changes in the relaxation parameter could affect the numerical solution of the nonlinear equations.

Sensitivity Approach of Optical Sensors of Cholesterol Detection through Gaussian Beam and Quasi-Gaussian Beam

Sensitivity is the comparison result between changes in output signal intensity and changes in input signal shift sensor. The purpose of this study was to analyze the sensitivity of fiber optic sensors using mathematical analysis through the Gaussian beam approach and quasi-Gaussian beam compared with the sensitivity of the optical sensor experimental results so that it can find the correct approach of sensitivity values between theory and experiment. The research method used mathematical analysis and experimental methods and mathematical descriptions for the description of the bundle optical fiber used in the experiment until the sensitivity equation is obtained. The results of the mathematical analysis of the Gaussian beam sensitivity values obtained of S = 0.004 mV ppm-1 and the sensitivity of quasi-Gaussian beam of S = 0.08 mV ppm-1. The results of the sensitivity of experimentally obtained S = 0.11 mV ppm-1. Based on the results of mathematical, experimental analysis, and sensor performance, sensitivity through the flat mirror reflection field, it can be concluded that the sensitivity of the optical fiber sensor tends to approach through the quasi-Gaussian beam approach to determine cholesterol concentration.