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In this paper, a new capacitive pressure sensor (CPS) is investigated and modeled by means of neural approach. The sensing principle in our pressure sensor is based on the determination of the change in the capacity induced by the applied pressure. A ring oscillator is used to convert the capacity variation of the pressure sensor to an output frequency. A multilayer perceptron neural network is used...
We propose a methodology of optimal path design for sensors through a distributed environment represented by a two or three-dimensional field quantity. We consider time-limited scenarios where the sensors can only make a small number of measurements, but where some portion of a physics-based model is available for the field of interest such as fluid flows, temperatures or concentrations. Thus the...
Despite the ever-widening use across different sectors, the lithium-ion batteries (LiBs) still face serious concerns over their thermal vulnerability. Motivated by this problem, this paper, for the first time, seeks to reconstruct the three-dimensional temperature field of a LiB pack in real time. The major challenge lies in how to acquire a high-fidelity reconstruction with constrained computation...
An optimized system management of a power system must take care of the actual operational and energetic duty of the power system distribution, promoting a high efficiency of power cables and avoiding their excessive gap on load and gap on lifetime. A procedure based on the Arrhenius model of the Thermal Aging of Insulating Materials allows implementing a tool to calculate the life loss and the residual...
Lithium-ion (Li-ion) battery faults are potentially hazardous to battery health, safety and performance. Thermal fault mechanisms represent a critical subset of such failures. To ensure safety and reliability, battery management systems must have the capability of diagnosing these thermal failures. We present a Partial Differential Equation (PDE) model-based scheme for diagnosing thermal faults in...
NOx sensor-based state estimations for urea-based selective catalytic reduction (SCR) systems have attracted much attention in the past several years because of their significant importance in achieving high NOx conversion efficiency and low ammonia slip as well as low operation cost. Most of the existing estimation techniques require sophisticated design processes and significant tuning effort, which...
This paper presents a backstepping control design for the one-phase Stefan problem with flowing liquid. The problem is modeled by a 1-D diffusion-advection Partial Differential Equation (PDE) defined on a time-varying spatial domain described by an ordinary differential equation (ODE). Based on our recent contribution, a nonlinear backstepping transformation for moving boundary problems is utilized,...
This paper presents a cascaded fiber interferometer sensor, which is fabricated by fusion splicing of single-mode fibers. The coupling and interference for the CFI were mathematically and experimentally studied. An equal model has been built for the CFI. Furthermore, the curvature sensitivity were explored in sensor application. The curvature sensitivity for the cascaded fiber interferometer is very...
Increased demand and economic constraints often cause the power system to be operated near its thermal limits and sometimes beyond. One way to mitigate this problem is to use the thermal overload protection functions built in to today's modern IED (Intelligent Electronic Device) relays that continuously monitor the thermal load in real time. These functions (ANSI 49) use very sophisticated algorithms...
High Voltage Shunt Capacitor Banks (SCBs) are the most economical and critical components in the power system, providing reactive power and voltage support. Over temperature, over voltages, manufacturing defects can cause internal failures of capacitor elements. With todays sensitive protection available in numerical relays capacitor elements failure will be detected and capacitor bank will be taken...
This paper reports a simple and effective method for generating a stable temperature gradient on a microfluidic plant chip. A thermo-electric cooling (TEC) plate is horizontally placed below an inclined microfluidic plant chip. The space between the TEC and the plant chip is filled with polydimethylsiloxane (PDMS). Due to different lengths of thermal pathways from the TEC to the plant chip, a stable...
This work consists of analyzing and simulating a parabolic trough collector in order to bring out the evolution of its thermal performances, mainly the heat transfer fluid outlet temperature, the useful power and the thermal efficiency, and this under weather conditions of Errachidia region, located at the Southeast of MOROCCO. The capturing system collects energy using water as a heat transfer fluid,...
This paper demonstrates, based on a practical example of a test hybrid circuit, the importance of proper modeling of the heat transfer coefficient dependence on the surface temperature rise and fluid velocity in air cooled electronic systems. Hybrid circuits usually have large surface area and consequently important temperature gradients could occur in them, hence the local values of the heat transfer...
Warpage of semiconductor packaging substrate during or after manufacturing processes has been a serious issue in the electronics industry. We found that the packaging substrate, which has initial warpage at room temperature, changes its warpage orientation by flipping from a concave to a convex cylindrical shape during the thermal processing. In this paper, we demonstrate that the rotation of warpage...
Epoxy mold compound (EMC) and optical grade silicone based materials have been widely used in manufacturing Light Emitting Diode (LED). Silicones are being used as encapsulant and lenses for next-generation LED packaging designs, such as chip on board (COB) LEDs. Silicones serve several roles including protective lenses, stress relieving encapsulant, mechanical protection and light path materials...
This paper presents the characterization of an infrared (IR) Longwave camera kit (Lepton-Flir), based on a bolometer array; for the telemetry measuring of temperature in the human skin. It is important to adapt the device to the measured material since the radiometry depends on the emissivity of the material in question. The characterization took place with the comparison with a thermocouple placed...
This paper presents a comprehensive model to analytically estimate the Zero Rate Level variation over temperature in micro machined Coriolis Vibratory Gyroscopes with associated electronics, with the goal of providing solid guidelines for the development of high stability MEMS Inertial Measurement Units. In fact, ZRL stability over temperature is a key parameter in various applications, especially...
This paper deals with coefficient of performance (COP) maximization of automotive R744 heat pump using Nelder-Mead simplex method. The COP maximum is searched using high-side pressure adjustment, what is possible and necessary during transcritical operation. Selected approach allows efficient heat pump operation, fast COP maximum localization, minimum number of needed actuator changes and resistance...
Recent interests in exploring the potential of renewable energy possibilities and readiness in sultanate of Oman has showed that it can engage renewable energy technologies, such as solar, wind power and various hybrid power models to mitigate fossil fuel limitations, revitalize additional economic development, create new jobs and preserve a cleaner environment. However, limited knowledge and information...
In this paper, an approach of designing a fast tracking MPPT is introduced using a predicted sixth order polynomial curve fitting MPPT technique. The results are compared with the lower order polynomials curve fitting MPPT and also compared with the Artificial Neuro-Fuzzy Inference System (ANFIS) results. The polynomials were generated from an offline solar data. This work was done to validate the...
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